Agenda packet — American Canyon City Council, February 21, 2023 (part 9 of 20)

1783
Habitat Probability on Project Site
Family
TaxonCommon Name Status* Flowering Period
Table 3
Special-Status Plants Known to Occur in the Vicinity of the Devlin Road Extension Project Site

MONK & ASSOCIATES
Area Locations
Adoxaceae
Viburnum ellipticum Fed: -
State: -
CNPS: Rank 2B.3
Chaparral; cismontane woodland; lower montane coniferous forest.

None. Not observed during appropriately timed surveys. No impact. Western viburnum May-July Record for this species located 4.7 miles north of the project site (Occurrence No. 7).

Apiaceae
Lilaeopsis masonii Fed: -
State: CR
CNPS: Rank 1B.1
Marshes and swamps (brackish or freshwater); riparian scrub.

None. Not observed during appropriately timed surveys. No impact. Mason's lilaeopsis April-October Record for this species located 2.6 miles northwest of the project site (Occurrence No. 10).

Asteraceae
Balsamorhiza macrolepis Fed: -
State: -
CNPS: Rank 1B.2
Cismontane woodland; chaparral; valley and foothill grassland; [sometimes serpentinite]. 90 - 1555 meters None. Not observed during appropriately timed surveys. No impact. Big-scale balsam-root March-June Record for this species located 2.9
miles southeast of the project site (Occurrence No. 7).

Erigeron greenei Fed: -
State: -
CNPS: Rank 1B.2
Chaparral (serpentinite). None. No suitable habitat onsite.

No impact expected. Narrow-leaved daisy May-September Record for this species located 4.2 miles north of the project site (Occurrence No. 16).

Lasthenia conjugens Fed: FE
State: -
CNPS: Rank 1B.1
Valley and foothill grassland (mesic); vernal pools.

None. Not observed during appropriately timed surveys. No impact expected. Contra Costa goldfields March-June Record for this species located 2.8
miles north of the project site (Occurrence No. 1).

Symphyotrichum lentum Fed: -
State: -
CNPS: Rank 1B.2
Marshes and swamps (brackish and fresh water)
None. Not observed during appropriately timed surveys. No impact. Suisun Marsh aster August-November Record for this species located 1.8 miles northwest of the project site (Occurrence No. 128).
1784 Page 1 of 4
Habitat Probability on Project Site
Family
TaxonCommon Name Status* Flowering Period
Table 3
Special-Status Plants Known to Occur in the Vicinity of the Devlin Road Extension Project Site

MONK & ASSOCIATES
Area Locations
Campanulaceae
Downingia pusilla Fed: -
State: -
CNPS: Rank 2.2
Valley and foothill grassland (mesic); vernal pools.

None. Not observed during appropriately timed surveys. No impact expected. Dwarf downingia March-May Record for this species located 2.4 miles north of the project site (Occurrence No. 108).

Legenere limosa Fed: -
State: -
CNPS: Rank 1B.1
Vernal pools. None. Not observed during
appropriately timed surveys. No impact expected. Legenere April-June Record for this species located 2.8 miles north of the project site (Occurrence No. 7).

Chenopodiaceae
Extriplex joaquinana Fed: -
State: -
CNPS: Rank 1B.2
Chenopod scrub; meadows; valley and foothill grassland; [alkaline].

None. No alkaline habitats onsite. Not observed during appropriately timed surveys. No impact expected.

San Joaquin spearscale
April-October Record for this species located 2.9 miles south of the project site (Occurrence No. 58).

Cyperaceae
Carex lyngbyei Fed: -
State: -
CNPS: Rank 2
Marshes or swamps (brackish or freshwater)
None. No marsh habitat onsite. Not observed during May or July surveys. No impact. Lyngbye's sedge May-August Record for this species located 2.2 miles west of the project site (Occurrence No. 28).

Fabaceae
Astragalus tener tener Fed: -
State: -
CNPS: Rank 1B.2
Playas; mesic grasslands (adobe clay), vernal pools (alkaline).

None. No suitable habitat onsite. Not observed in March-May surveys. No impact. Alkali milkvetch March-June Record for this species located 2.8
miles south of the project site (Occurrence No. 50).
1785 Page 2 of 4
Habitat Probability on Project Site
Family
TaxonCommon Name Status* Flowering Period
Table 3
Special-Status Plants Known to Occur in the Vicinity of the Devlin Road Extension Project Site

MONK & ASSOCIATES
Area Locations
Lathyrus jepsonii jepsonii Fed: -
State: -
CNPS: Rank 1B.2
Marshes and swamps (freshwater and brackish).

None. No suitable habitat onsite. No impact expected. Delta tule pea May-September Record for this species located 1.8 miles north of the project site (Occurrence No. 4).

Trifolium amoenum Fed: FE
State: -
CNPS: Rank 1B.1
Valley and foothill grassland (sometimes serpentinite)
None. Not observed during appropriately timed surveys. No impact expected. Showy Indian clover April-June Record for this species located 2.0 miles southeast of the project site (Occurrence No. 23).

Trifolium hydrophilum Fed: -
State: -
CNPS: Rank 1B.2
Marshes and swamps; valley and foothill grassland (mesic, alkaline); vernal pools. 0-300 m.

None. Not observed during appropriately timed surveys. No impact expected. Saline clover April-June Record for this species located 2.8 miles north of the project site (Occurrence No. 35).

Orobanchaceae
Castilleja affinis neglecta Fed: FE
State: CT
CNPS: Rank 1B.2
Valley and foothill grassland [serpentinite]
None. No serpentinite onsite. No impact expected. Tiburon paintbrush April-June Record for this species located 2.9 miles southeast of the project site (Occurrence No. 5).

Chloropyron molle molle Fed: FE
State: CR
CNPS: Rank 1B.2
Marshes and swamps (coastal salt).

None. No salt marsh onsite. No impact expected. Soft salty bird's-beak July-September Record for this species located 1.5 miles northwest of the project site (Occurrence No. 3).

Rhamnaceae
Ceanothus purpureus Fed: -
State: -
CNPS: Rank 1B.2
Chaparral (volcanic). None. No ceanothus observed
onsite. No impact expected. Holly-leaf ceanothus February-April Record for this species located 4.7 miles north of the project site (Occurrence No. 47). 1786 Page 3 of 4
Habitat Probability on Project Site
Family
TaxonCommon Name Status* Flowering Period
Table 3
Special-Status Plants Known to Occur in the Vicinity of the Devlin Road Extension Project Site

MONK & ASSOCIATES
Area Locations
Themidaceae
Brodiaea leptandra Fed: -
State: -
CNPS: Rank 1B.2
Broadleafed upland forest; chaparral; cismontane woodland; lower montane coniferous forest; valley and foothill grassland. Elevation 110 - 915 meters.

None. Not observed during appropriately timed surveys. Marginal habitat onsite. No impact expected.

Narrow-anthered California brodiaea
May-July Record for this species located 4.3 miles north of the project site (Occurrence No. 30).
*StatusFederal:FE - Federal EndangeredFT - Federal ThreatenedFPE - Federal Proposed EndangeredFPT - Federal Proposed ThreatenedFC - Federal Candidate State:CE - California EndangeredCT - California ThreatenedCR - California RareCC - California CandidateCSC - California Species of Special Concern CNPS Continued:Rank 2 - Plants rare, threatened, or endangered in California, but more common elsewhereRank 2A - Extirpated in California, common elsewhereRank 2B.1 - Seriously endangered in California, but more common elsewhereRank 2B.2 - Fairly endangered in California, but more common elsewhereRank 2B.3 - Not very endangered in California, but more common elsewhereRank 3 - Plants about which we need more information (Review List)Rank 3.1 - Plants about which we need more information (Review List) Seriously endangered in CaliforniaRank 3.2 - Plants about which we need more information (Review List) Fairly endangered in CaliforniaRank 4 - Plants of limited distribution - a watch list CNPS:Rank 1A - Presumed extinct in CaliforniaRank 1B - Plants rare, threatened, or endangered in California and elsewhereRank 1B.1 - Seriously endangered in California (over 80% occurrences threatened/ high degree and immediacy of threat)Rank 1B.2 - Fairly endangered in California (20-80% occurrences threatened)Rank 1B.3 - Not very endangered in California (<20% of occurrences threatened or no current threats known) 1787 Page 4 of 4
*Status Habitat Closest Locations Probability on Project Site Table 4
Special-Status Animal Species Known to Occur in the Vicinity of the Devlin Road/Vine Trail Extension Project Site Species
monk & associates
Invertebrates
Branchinecta lynchi
Record for this species located 0.9
miles west of the project site
(Occurrence No. 232).

None. Protocol level surveys conducted onsite;
none found. See text.

Insects
Speyeria callippe callippe
Record for this species located 2.0
miles east of the project site
(Occurrence No. 14).

None. No suitable habitat and no Viola (host
plant) onsite. No impact expected.

Fed: FE
State: -
Occurs in grassland habitats and shrubby
woodlands around San Francisco Bay. Viola
pedunculata is the host plant. Males
congregate on hilltops.

Callippe silverspot butterfly
Other:

Fish
Oncorhynchus mykiss irideus
Record for this species located 1.5
miles south of the project site
(Occurrence No. 4).

None. No creeks or perennial drainages onsite.

No impact expected.

Fed: FT
State: -
From Russian River south to Soquel Creek,
and to Pajaro River. Also found in San
Francisco & San Pablo Bay Basins. Spawn in
clear, cool, well oxygenated streams greater
than 18 cm deep.

Steelhead - Central California Coast DPS
Other:

Hypomesus transpacificus
Record for this species located 4.5
miles southwest of the project site
(Occurrence No. 5).

None. No creeks or perennial drainages on the
project site. No impact expected.

Fed: FT
State: CT
Endemic to the Sacramento-San Joaquin
Delta. Occurs seasonally in Suisun and San
Pablo bays. Spawning usually occurs in deadend sloughs and shallow channels.

Delta smelt
Other:

Spirinichus thaleichthys
Record for this species located 2.5
miles west of the project site
(Occurrence No. 26).

None. No creeks or perennial drainages onsite.

No impact expected.

Fed: --
State: CT
Endemic to the Sacramento-San Joaquin
River system. Inhabits open waters in the
Delta and Suisun Bay. After spawning, larvae
are carried downstream to brackish nursery
areas.

Longfin smelt
Other:

Page 1 of 5 ends

1788
*Status Habitat Closest Locations Probability on Project Site Table 4
Special-Status Animal Species Known to Occur in the Vicinity of the Devlin Road/Vine Trail Extension Project Site Species
monk & associates
Pogonichthys macrolepidotus
Record for this species located 3.9
miles south of the project site
(Occurrence No. 12).

None. No creeks or perennial drainages onsite.

No impact expected.

Fed:

State: CSC
Endemic to the lakes and rivers of the Central
Valley; now confined to the delta, Suisun
Bay, and associated marshes. Inhabits slow
moving river sections and dead-end sloughs.

Needs flooded vegetation for spawning.

Sacramento splittail
Other:

Amphibians
Rana draytonii
Record for this species located 1.6
miles east of the project site
(Occurrence No. 1062).

None. No perennial water or long-term
inundation onsite or adjacent to project site.

See text.

Fed: FT
State: CSC
Occurs in lowlands and foothills in deeper
pools and streams, usually with emergent
wetland vegetation. Requires 11-20 weeks of
permanent water for larval development.

California red-legged frog
Other:

Reptiles
Actinemys marmorata marmorata
Record for this species located 0.7
miles south of the project site
(Occurrence No. 552).

None. No perennial water or long-term
inundation onsite or adjacent to the site to
support this turtle. No impact expected.

Fed: -
State: CSC
Inhabits ponds, marshes, rivers, streams, and
irrigation ditches with aquatic vegetation.

Needs suitable basking sites and upland
habitat for egg laying. Occurs in the Central
Valley and Contra Costa County.

Western pond turtle
Other:

Birds
Circus cyaneus
Record for this species located 3.0
miles west of the project site
(Occurrence No. 29).

Moderate. Could nest in the upland grassland
community. Preconstruction surveys
necessary. See text.

Fed: -
State: CSC
Nests on the ground or in shrubby vegetation
typically in grasslands, fallow farm lands,
near freshwater and salt water marshes.

Northern harrier
Other:

Buteo swainsoni
Record for this species located 2.0
miles north of the project site
(Occurrence No. 1718).

Low to none. No suitable habitat onsite, but
nearby eucalyptus trees provide nesting habitat.

Preconstruction surveys would need to be
conducted. See text.

Fed: -
State: CT
Migratory and resident raptor that breeds in
open areas with scattered trees. Prefers
riparian and sparse oak woodland habitats for
nesting. Requires nearby grasslands, grain
fields, or alfalfa for foraging.

Swainson's hawk
Other:

Page 2 of 5 ends

1789
*Status Habitat Closest Locations Probability on Project Site Table 4
Special-Status Animal Species Known to Occur in the Vicinity of the Devlin Road/Vine Trail Extension Project Site Species
monk & associates
Buteo regalis
Record for this species located 0.8
miles north of the project site
(Occurrence No. 28).

None. Does not nest in California. May forage
onsite on occasion. Foraging habitat not
protected pursuant to CEQA. No impact.

Fed: --
State: WL
Winter migrant to California where they
prefer grasslands, cultivated fields and arid
areas with an abundance of prey species, such
as pocket gophers, black-tailed hares, and
cottontails.

Ferruginous hawk
Other:

Aquila chrysaetos
Record for this species located 3.3
miles northwest of the project site
(Occurrence No. 82).

Low. No trees onsite but may nest in
Eucalyptus trees adjacent to the site.

Preconstruction survery necessary. See text.

Fed: -
State: WL
Found in rolling foothill grassland with
scattered trees. Nests on cliffs and in large
trees in open areas.

Golden eagle
Other: FP
Falco peregrinus anatum
Record for this species located 4.8
miles southeast of the project site
(Occurrence No. 42).

None. No nesting habitat onsite. May forage
over the site on occasion but impacts to
foraging habitat not significant pursuant to
CEQA. No impact to individuals or nesting
habitat expected.

Fed: -
State: CE
Nests on high cliffs. Also nests on humanmade structures. Nest consists of a scrape on a depression or ledge in an open site.

American peregrine falcon
Other:

Laterallus jamaicensis coturniculus
Record for this species located 1.4
miles northwest of the project site
(Occurrence No. 31).

None. No salt marsh habitat onsite or near the
site. No nesting habitat onsite. No impact
expected.

Fed: --
State: CT
Inhabits salt marshes bordering larger bays.

Prefers tidal salt marshes of pickleweed.

California black rail
Other:

Rallus obsoletus obsoletus
Record for this species located 1.4
miles northwest of the project site
(Occurrence No. 16).

None. No habitat onsite or near the site. No
impact expected.

Fed: FE
State: CE
Inhabits salt water and brackish marshes with
tidal sloughs in San Francisco Bay. Prefers
dense pickleweed for cover, but forages for
invertebrates along mud-bottomed sloughs.

California Ridgway's rail
Other:

Charadrius alexandrinus nivosus
Record for this species located 3.5
miles west of the project site
(Occurrence No. 121).

None. No suitable habitat onsite or near the
site. No impact expected.

Fed: FT
State: CSC
Prefers sandy beaches, salt pond levees, and
shores of large alkali lakes. Requires sandy,
gravelly, or friable soil for nesting.

Western snowy plover
Other:

Page 3 of 5 ends

1790
*Status Habitat Closest Locations Probability on Project Site Table 4
Special-Status Animal Species Known to Occur in the Vicinity of the Devlin Road/Vine Trail Extension Project Site Species
monk & associates
Hydroprogne caspia
Record for this species located 4.9
miles south of the project site
(Occurrence No. 2).

None. No suitable habitat on project site. No
impact expected.

Fed: -
State: -
Common along the coast and at scattered
locations inland. Breeds in small colonies
mostly along the coast; may breed in lakes
and fresh or brackish water bays.

Caspian tern
Other:

Athene cunicularia hypugaea
Record for this species located 1.8
miles north of the project site
(Occurrence No. 935).

None. No burrows onsite for nesting. No
impact expected.

Fed: --
State: CSC
Found in open, dry annual or perennial
grasslands, deserts and scrublands
characterized by low-growing vegetation.

Subterranean nester, dependent upon
burrowing mammals, most notably, the
California ground squirrel.

Western burrowing owl
Other:

Geothlypis trichas sinuosa
Record for this species located 1.2
miles northwest of the project site
(Occurrence No. 37).

None. No sutiable habitat onsite. No impact
expected.

Fed: -
State: CSC
Resident of freshwater and salt water marshes
in the San Francisco Bay region. Requires
thick, continuous cover for foraging and tall
grasses, tules, or willows for nesting.

Salt marsh common yellowthroat
Other:

Melospiza melodia samuelis
Record for this species located 2.2
miles northwest of the project site
(Occurrence No. 16).

None. No suitable habitat onsite. No impact
expected.

Fed: --
State: CSC
More properly known as Samuels Song
Sparrow. Resident of salt marshes along the
north side of San Francisco and San Pablo
Bays. Inhabits tidal sloughs in the California
marshes; nests in grindelia bordering slough
channels.

San Pablo song sparrow
Other:

Agelaius tricolor
Record for this species located 0.3
miles north of the project site
(Occurrence No. 243).

None. No suitable habitat onsite. No impact
expected.

Fed: -
State: CC
Colonial nester in dense cattails, tules,
brambles or other dense vegetation. Requires
open water, dense vegetation, and open
grassy areas for foraging.

Tricolored blackbird
Other: CSC
Mammals
Sorex ornatus sinuosus
Record for this species located 4.3
miles south of the proejct site
(Occurrence No. 2).

None. No suitable habitat onsite. No impact
expected.

Fed: --
State: CSC
Inhabits tidal marshes in the northern end of
San Pablo and Suisun Bays. Requires dense,
low cover of plants, driftwood, and other
litter above the mean high tide line.

Suisun shrew
Other:

Page 4 of 5 ends

1791
*Status Habitat Closest Locations Probability on Project Site Table 4
Special-Status Animal Species Known to Occur in the Vicinity of the Devlin Road/Vine Trail Extension Project Site Species
monk & associates
Antrozous pallidus
Record for this species located 4.2
miles northwest of the project site
(Occurrence No. 57).

None. No suitable habitat onsite. No impact
expected.

Fed: -
State: CSC
Occurs in deserts, grasslands, shrublands,
woodlands, and forests. Most common in dry
habitats with rocky areas for roosting. Roosts
in caves, crevices, mines, and occasionally
hollow trees. Night roosts in open areas such
as porches and open buildings.

Pallid bat
Other:

Reithrodontomys raviventris
Record for this species located 1.2
miles northwest of the project site
(Occurrence No. 48).

None. No suitable habitat onsite. No impact
expected.

Fed: FE
State: CE
Inhabits saline marshes in the San Francisco
Estuary. Prefers pickleweed marshes.

Requires higher areas for escaping high water.

Salt marsh harvest mouse
Other:

Taxidea taxus
Record for this species located 4.6
miles northwest of the project site
(Occurrence No. 203).

None. No suitable habitat onsite. No impact
expected.

Fed: -
State: CSC
Most abundant in drier open stages of most
shrub, forest, and herbaceous habitats, with
friable soils. Need sufficient food, friable
soils & open, uncultivated ground. Prey on
burrowing rodents. Dig burrows.

American badger
Other:
*Status
Federal:

FE - Federal Endangered
FT - Federal Threatened
FPE - Federal Proposed Endangered
FPT - Federal Proposed Threatened
FC - Federal Candidate
FPD - Federally Proposed for delisting
State:

CE - California Endangered
CT - California Threatened
CR - California Rare
CC - California Candidate
CSC - California Species of Special Concern
FP - Fully Protected
WL - Watch List. Not protected pursuant to CEQA

Page 5 of 5 ends

1792
1793
1794

THIS PAGE INTENTIONALLY LEFT BLANK
1795
City of American Canyon—Giovannoni Logistics Center Project Draft EIR
FirstCarbon Solutions
C.7 - M& A 2019 Green Island Road Widening Biological Resources Assessment
C-529
1796

THIS PAGE INTENTIONALLY LEFT BLANK
1797

MONK & ASSOCIATES
Environmental Consultants

1136 Saranap Ave., Suite Q ♦ Walnut Creek ♦ California ♦ 94595 (925) 947-4867 ♦ FAX (925) 947-1165

BIOLOGICAL RESOURCES ANALYSIS

GREEN ISLAND ROAD RECONSTRUCTION AND WIDENING PROJECT

CITY OF AMERICAN CANYON, CALIFORNIA
July 1, 2019
Prepared for
City of American Canyon
4381 Broadway Suite 201
American Canyon, California 94503
Attention: Mr. Ronald Ranada
Prepared by
Monk & Associates, Inc.
1136 Saranap Avenue, Suite Q
Walnut Creek, California 94595
Contact: Ms. Hope Kingma
1798
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
i

MONK & ASSOCIATES

TABLE OF CONTENTS

1. INTRODUCTION ............................................................................................................................ 1

2. PROPERTY LOCATION AND SETTING .................................................................................... 1

3. PROPOSED PROJECT .................................................................................................................... 1

4. ANALYSIS METHODS .................................................................................................................. 2

5. RESULTS OF RESEARCH AND PROJECT SITE ANALYSES ................................................ 3

5.1 Soils .......................................................................................................................................... 3

5.1.1 CLEAR LAKE CLAY, DRAINED (116) ....................................................................................... 3

5.1.2 HAIRE LOAM, 2 TO 9 PERCENT SLOPES (146) ......................................................................... 3

5.2 Project Site Topography and Hydrology ................................................................................ 3

5.3 Plant Communities and Associated Wildlife Habitats ........................................................... 3

5.3.1 RUDERAL HERBACEOUS HABITAT ............................................................................................ 4

5.3.2 POTENTIAL SEASONAL WETLANDS .......................................................................................... 4

5.4 Wildlife Corridors .................................................................................................................... 5

6. SPECIAL-STATUS SPECIES DEFINITION ................................................................................. 5

6.1 Definitions ................................................................................................................................ 5

6.2 Potential Special-Status Plants on the Project Site ................................................................. 8

6.3 Potential Special-Status Animals in the Project Site .............................................................. 8

6.3.1 VERNAL POOL FAIRY SHRIMP ................................................................................................... 8

6.3.2 CALIFORNIA RED-LEGGED FROG ............................................................................................. 9

6.3.3 NORTHERN HARRIER .............................................................................................................. 10

6.3.4 SWAINSON’S HAWK ................................................................................................................ 10

7. REGULATORY FRAMEWORK FOR NATIVE WILDLIFE, FISH, AND PLANTS .............. 12

7.1 Federal Endangered Species Act ........................................................................................... 12

7.1.1 RESPONSIBLE AGENCY .......................................................................................................... 14

7.1.2 APPLICABILITY TO THE PROPOSED PROJECT ......................................................................... 14

7.2 Federal Migratory Bird Treaty Act ....................................................................................... 14

7.2.1 APPLICABILITY TO THE PROPOSED PROJECT ........................................................................ 15

7.3 California Endangered Species Act ...................................................................................... 15

7.3.1 SECTION 2081 OF THE CALIFORNIA ENDANGERED SPECIES ACT ........................................ 15

7.3.2 APPLICABILITY TO THE PROPOSED PROJECT ........................................................................ 16

7.4 California Fish and Game Code § 3503, 3503.5, 3511, and 3513 ....................................... 17

7.4.1 APPLICABILITY TO THE PROPOSED PROJECT ........................................................................ 17

7.5 City of American Canyon General Plan ............................................................................... 17

7.5.1 APPLICABILITY TO THE PROPOSED PROJECT ........................................................................ 19

8. REGULATORY REQUIREMENTS PERTAINING TO WATERS OF THE UNITED STATES AND STATE .................................................................................................................................. 20

8.1 U.S. Army Corps of Engineers Jurisdiction and General Permitting .................................. 20

8.1.1 SECTION 404 OF THE CLEAN WATER ACT ............................................................................ 20

8.1.2 APPLICABILITY TO THE PROPOSED PROJECT ........................................................................ 23

8.2 California Regional Water Quality Control Board (RWQCB) ............................................ 24

8.2.1 SECTION 401 OF THE CLEAN WATER ACT ............................................................................ 24

8.2.2 APPLICABILITY TO THE PROPOSED PROJECT ........................................................................ 25

8.2.3 PORTER-COLOGNE WATER QUALITY CONTROL ACT .......................................................... 25

8.2.4 APPLICABILITY TO THE PROPOSED PROJECT ........................................................................ 26 1799
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
ii

MONK & ASSOCIATES

9. STATE WATER RESOURCES CONTROL BOARD (SWRCB)/RWQCB – STORM WATER MANAGEMENT ........................................................................................................................... 26

9.1 Construction General Permit ................................................................................................. 26

9.1.1 APPLICABILITY TO THE PROPOSED PROJECT ........................................................................ 28

9.2 RWQCB Municipal Storm Water Permitting Programs ...................................................... 29

9.2.1 NPDES C.3 REQUIREMENTS ................................................................................................. 29

9.2.2 APPLICABILITY TO THE PROPOSED PROJECT ........................................................................ 30

9.3 California Department of Fish and Wildlife Protections ...................................................... 30

9.3.1 SECTION 1602 OF CALIFORNIA FISH AND GAME CODE ........................................................ 30

9.3.2 APPLICABILITY TO THE PROPOSED PROJECT ........................................................................ 31

10. CALIFORNIA ENVIRONMENTAL QUALITY ACT (CEQA) REGULATIONS ................. 31

10.1.1 APPLICABILITY TO THE PROPOSED PROJECT ...................................................................... 32

11. IMPACTS ANALYSIS ................................................................................................................ 32

11.1 Significance Criteria ............................................................................................................ 32

11.1.1 THRESHOLDS OF SIGNIFICANCE .......................................................................................... 32

12. IMPACT ASSESSMENT AND PROPOSED MITIGATION ................................................... 33

12.1 Impact BIO-1. Proposed project could have a potentially significant impact on nesting Swainson’s hawk (Potentially Significant) ................................................................................. 34

12.2 Mitigation Measure BIO-1: Swainson’s Hawk .................................................................. 34

12.3 Impact BIO-2. Proposed project could have a potentially significant impact on Tree Nesting Raptors (excluding Swainson’s hawk which is discussed separately) (Potentially Significant) ................................................................................................................................... 35

12.4 Mitigation Measure BIO-2: Tree Nesting Raptors ............................................................. 35

12.5 Impact BIO-3. Proposed project could have a potentially significant impact on Other Nesting Birds (Potentially Significant) ....................................................................................... 36

12.6 Mitigation Measure BIO-3: Other Nesting Birds ............................................................... 36

12.7 Impact BIO-4. Proposed project will have a significant impact on Waters of the United States/ State (Significant) ............................................................................................................ 37

12.8 Mitigation Measure BIO-4: Waters of the United States/State .......................................... 37

13. LITERATURE CITED ................................................................................................................. 39

1800
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
iii

MONK & ASSOCIATES

FIGURES
(At Back of Report)
Figure 1. Regional Map of the Green Island Road Reconstruction and Widening Project Site.

Figure 2. Local Map of the Green Island Road Reconstruction and Widening Project Site.

Figure 3. Aerial Photograph of the Green Island Road Reconstruction and Widening Project Site.

Figure 4. Soil Types of the Green Island Road Reconstruction and Widening Project Site.

Figure 5. Known Records for Special-Status Species Within 3 Miles of the Green Island Road Reconstruction and Widening Project Site.

Figure 6. USFWS Critical Habitat in the Vicinity of the Green Island Road Reconstruction and Widening Project Site.

TABLES
(At Back of Report)
Table 1. Plant Species Observed on the Green Island Road Reconstruction and Widening Project Site.

Table 2. Wildlife Species Observed on the Green Island Road Reconstruction and Widening Project Site.

Table 3. Special-Status Plant Species Known to Occur in the Vicinity of the Green Island Road Reconstruction and Widening Project Site.

Table 4. Special-Status Animal Species Known to Occur in the Vicinity of the Green Island Road Reconstruction and Widening Project Site.

Table A. Trees Survey Data – Green Island Road Reconstruction and Widening Project Site.

1801
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
iv

MONK & ASSOCIATES
SHEETS
(At Back of Report)
Sheet A. Property Owners affected by the Green Island Road Reconstruction and Widening Project Site, City of American Canyon, California.

Sheet B. Assessor’s Parcel Numbers for Green Island Road Reconstruction and Widening Project Site, City of American Canyon, California.

Sheets 1-5. Preliminary Aquatic Resources Delineation Maps for the Green Island Road Reconstruction and Widening Project Site, City of American Canyon, California.

EXHIBITS
(At Back of Report)
Exhibits A-C. Tree Survey, Green Island Road Reconstruction and Widening Project Site, City of American Canyon, California.
1802
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
1 MONK & ASSOCIATES

1. INTRODUCTION
Monk & Associates, Inc. (M&A) has prepared this Biological Resources Analysis for the proposed road widening improvements to existing Green Island Road and rehabilitation of the existing pavement structure of Green Island Road, Jim Oswalt Way, Mezzetta Court, Commerce Boulevard, and Hanna Drive all located within the City of American Canyon, California (Figures 1 and 2). The portion of Green Island Road that will be widened and existing pavement areas on Green Island Road, Jim Oswalt Way, Mezzetta Court, Commerce Boulevard, and Hanna Drive that are to be rehabilitated are hereinafter referred to as the Project Site. The purpose of our analysis is to provide a description of existing biological resources on the project site and to identify potentially significant impacts that could occur to sensitive biological resources from the proposed Green Island Road Widening Project (the project).

Biological resources include common plant and animal species, and special-status plants and animals as designated by the U.S. Fish and Wildlife Service (USFWS), California Department of Fish and Wildlife (CDFW), National Marine Fisheries Service (NMFS), and other resource organizations including the California Native Plant Society. Biological resources also include waters of the United States and State, as regulated by the U.S. Army Corps of Engineers (Corps), California Regional Water Quality Control Board (RWQCB), and CDFW. It is important to note that our analysis includes an assessment of the potential for impacts to regulated waters and includes a formal delineation of “waters of the U.S.” that is pending submittal to the Corps, the regulatory agency that defines waters of the U.S.

This Biological Resources Analysis provides a regulatory review of environmental regulations that have applicability to the proposed project. Finally, this analysis also provides mitigation measures for “potentially significant” and “significant” impacts that could occur to biological resources from the implementation of the project. Whenever possible, upon implementation, the prescribed mitigation measures would reduce impacts to levels considered less than significant pursuant to the California Environmental Quality Act (CEQA) (Pub. Resources Code §§ 21000 et seq.; 14 Cal.

Code Regs. §§ 15000 et seq). Accordingly, this report is suitable for review and inclusion in any review being conducted by the City of American Canyon for the proposed project pursuant to the CEQA.

2. PROPERTY LOCATION AND SETTING
The project site is located in the City of American Canyon, west of Highway 29. The road widening portion of the project along Green Island Road is approximately 0.8 miles in length.

Most of the properties along Green Island Road have been recently developed into shipping and storage warehouses, and other commercial properties; however, there are a few remaining ranchettes along this road. Figure 3 provides an aerial photograph of the limits of the project site.

3. PROPOSED PROJECT
The City of American Canyon is proposing to widen Green Island Road, including rehabilitation of the existing pavement area, to facilitate trucking commerce to and from Highway 29 which has increased over the years due to the addition of commercial warehouses along this formerly 1803
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
2 MONK & ASSOCIATES
rural road. The limits of the Green Island Road widening portion of the project extend approximately 35 feet north of the existing unimproved edge of Green Island Road into privately owned properties. In order to accommodate the road widening the City will relocate underground all overhead utility lines currently present along the road or on the adjacent private property lands that become incorporated into the new road. A bike path is also proposed to be added along the northern side of Green Island Road as part of this project. In addition to improvements to Green Island Road, the City of American Canyon proposes to rehabilitate the existing pavement areas of Jim Oswalt Way, Mezzetta Court, Commerce Boulevard, and Hanna Drive.

4. ANALYSIS METHODS
Prior to preparing this Biological Resources Analysis, M&A researched the most recent version of CDFW’s Natural Diversity Database, RareFind 5 application (CNDDB 2019) for records of special-status plant and animal species (that is, threatened, endangered, rare) known to occur in the region of the project site. M&A also searched the 2019 electronic version of the California Native Plant Society’s (CNPS) Inventory of Rare and Endangered Plants of California (CNPS 2001) for records of special-status plants known in the region of the project site. All specialstatus species records were compiled into tables. M&A examined all known record locations for special-status species to determine if special-status species could occur on the project site or within an area of affect.

On May 11, 2017, M&A biologists, Ms. Hope Kingma and Mr. Devin Jokerst, visited the project site to examine potential Corps regulated areas along the north side of Green Island Road. M&A used the Corps’ 1987 Wetlands Delineation Manual (Corps 1987) in conjunction with the regional supplement for the Arid West Region (Corps 2008) to conduct this wetland delineation.

On August 3, 2017, M&A conducted an additional delineation along the south side of Green Island Road to examine all areas within the limits of the project site. A jurisdictional determination request and Draft Aquatic Resources Delineation Maps (Sheets 1-5) were prepared and is pending submittal to the Corps.

M&A conducted a tree survey within the limits of the project site on August 3, 2017. M&A assessed the health and vigor of each tree, installed a tree tag on each tree, and measured the diameter at breast height (DBH) of each tree. DBH is measured using a diameter tape wrapped around the tree at 1.3 meters above the ground. All trees along the project site are shown on Exhibits A-C. The information collected via the tree survey is being utilized to support the project design and construction plans, to identify necessary tree removals and, as necessary, will be used to inform mitigation measures to address potential impacts associated with the removal of trees (e.g. potential impacts to nesting birds, etc.).

The results of our literature research and field surveys are provided in the sections below. 1804
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
3 MONK & ASSOCIATES

5. RESULTS OF RESEARCH AND PROJECT SITE ANALYSES

5.1 Soils
The U.S. Department of Agriculture (USDA), Natural Resources Conservation Service (NRCS 2017), Web Soil Survey Map of Napa County, California mapped two soil series on the project site: Clear Lake Clay, drained and Haire Loam, 2 to 9 percent slopes (Figure 4).

5.1.1 CLEAR LAKE CLAY, DRAINED (116)
Clear Lake soils are nearly level, poorly-drained soils, existing on old alluvial fans, in basins, and in swales of level drainageways. These soils formed in alluvium derived from sandstone and shale or other mixed rock sources. The plant cover consists of annual grasses and forbs and scattered oaks. Runoff is slow or very slow, with little hazard of erosion. The upper few inches of this soil commonly becomes strongly granular upon drying. This soil is mainly used for pasture. Some areas in the northern part of Napa Valley are used for vineyards. Clear Lake Clay, drained, is classified as a hydric soil by the NRCS (2017). The majority of the project site is mapped as Clear Lake Clay soils.

5.1.2 HAIRE LOAM, 2 TO 9 PERCENT SLOPES (146)
The Haire Soil series consists of moderately well-drained soils that occur on nearly level to moderately steep hills, on old terraces, and alluvial fans. Slope ranges from 0 to 30 percent, and elevation ranges from 20 to 300 feet. These soils formed from alluvium derived from sedimentary rock. The vegetation in uncultivated areas consists of annual grasses and forbs.

Permeability is very slow, and the hazard of erosion is slight. Haire soils are mainly used for dryland and irrigated pasture, but some areas are used for vineyards and rangeland. Haire loam, 2 to 9 percent slopes is classified as a hydric soil by the NRCS (2017).

5.2 Project Site Topography and Hydrology
The Project Site is located between the hills of the Newell Preserve and the tidal marshlands along the Napa River. While the project site is relatively flat, there is a gradual slope from the project site’s eastern boundary (approximately 58 feet above sea-level) to the project site’s western boundary (22 feet above sea-level). The roadside ditches along the northern shoulder of Green Island Road convey surface sheet flows draining from the impervious surfaces along Green Island Road. These potential Corps jurisdictional “other waters” drain into the existing stormdrain system along Green Island Road. Proposed rehabilitation of Jim Oswalt Way, Mezzetta Court, Commerce Boulevard, and Hanna Drive will not modify existing stormwater drainage that enters the City’s storm drain system.

5.3 Plant Communities and Associated Wildlife Habitats
Green Island Road widening will affect heretofore undeveloped surfaces that support ruderal and in some areas wetland habitats. Trees would likely be impacted by proposed widening. These affected habitats are analyzed in detail below. In contrast, Jim Oswalt Way, Mezzetta Court, Commerce Boulevard, and Hanna Drive are fully developed areas. Rehabilitating these existing heavily used streets will not result in biological impacts, or in impacts to trees, and thus the 1805
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
4 MONK & ASSOCIATES
effects of rehabilitating these streets is not analyzed at the same level of detail as the widening of Green Island Road.

A complete list of plant species observed on the project site is presented in Table 1.

Nomenclature used for plant names follows The Jepson Manual Second Edition (Baldwin 2012) and changes made to this manual as published on the Jepson Interchange Project website (http://ucjeps.berkeley.edu/interchange/index.html). Table 2 is a list of wildlife species observed on the project site. Nomenclature for wildlife follows CDFW’s Complete List of Amphibian, Reptile, Bird, and Mammal Species in California (2016) and any changes made to species nomenclature as published in scientific journals since the publication of CDFW’s list.

5.3.1 RUDERAL HERBACEOUS HABITAT
The vegetation along Green Island Road can be described as ruderal herbaceous. Ruderal (weedy) communities are assemblages of non-native plants that thrive in waste areas, roadsides and other sites that have been disturbed by human activity. Ruderal communities are typically found in hardpacked soils of roadsides, parking lots, industrial areas and construction sites.

Ruderal vegetation is adapted to high levels of disturbance and persists almost indefinitely in areas with continuous disturbance.

The ruderal herbaceous vegetation along Green Island Road is dominated by non-native grass species which include slender wild oat (Avena barbata), Italian ryegrass (Festuca perennis), foxtail chess (Bromus madritensis ssp. madritensis), and hare barley (Hordeum murinum ssp. leporinum). Dominant non-native forbs (broad-leaved plants) found in the project site include cut-leaf geranium (Geranium dissectum), bristly ox-tongue (Helminthotheca echioides), bind weed (Convolvulus arvensis), and curly dock (Rumex crispus).

Ruderal habitats typically provide suitable environments for common animals that are adapted to living in association with humans. Common wildlife species observed using this ruderal community included raccoon (Procyon lotor), Botta’s pocket gopher (Thomomys bottae), Eurasian collared-dove (Streptopelia decaocto), mourning dove (Zenaida macroura), western scrub jay (Aphelocoma californica), American crow (Corvus brachyrhynchos), northern mockingbird (Mimus polyglottos), European starling (Sturnus vulgaris), Brewer’s blackbird (Euphagus cyanocephalus), house finch (Haemorhous mexicanus), and house sparrow (Passer domesticus).

5.3.2 POTENTIAL SEASONAL WETLANDS
Potential seasonal wetlands are mapped alongside Green Island Road. These wetlands typically support wetland plant species including spiny buttercup (Ranunculus muricatus), rabbit’s foot grass (Polypogon monspilensis), bristly ox-tongue, hyssop loosestrife (Lythrum hyssopifolia), and Mediterranean barley (Hordeum marinum ssp. gussoneanum). Sub-dominant native hydrophytic species included California coyote-thistle (Eryngium aristulatum var. aristulatum), wavy-stemmed popcorn flower (Plagiobothrys undulatus), water plantain (Alisma triviale), and creeping spikerush (Eleocharis macrostachya).
1806
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
5 MONK & ASSOCIATES
Seasonal wetlands provide wildlife with a seasonal water source that allows animals to drink and forage in the water during the winter and spring months and sometimes into the early summer.

Amphibians will lay their eggs in seasonal wetland habitats and complete much of their life cycle in the wetlands. Invertebrates such as mayflies (Ephemeroptera), damselflies (Odonata), and predaceous diving beetles (Dytiscidae) are commonly associated with inundated seasonal wetland habitats and complete their life cycle in the wetlands. Wildlife species associated with these wetlands include Sierran tree frog (Pseudacris sierra), raccoon, black phoebe (Sayornis nigricans), cliff swallow (Petrochelidon pyrrhonota), and western meadowlark (Sturnella neglecta).

5.4 Wildlife Corridors
Wildlife corridors are linear and/or regional habitats that provide connectivity to other natural vegetation communities within a landscape fractured by urbanization and other development.

Wildlife corridors have several functions: 1) they provide avenues along which wide-ranging animals can travel, migrate, and breed, allowing genetic interchange to occur; 2) populations can move in response to environmental changes and natural disasters; and 3) individuals can recolonize habitats from which populations have been locally extirpated (Beier and Loe 1992).

All three of these functions can be met if both regional and local wildlife corridors are accessible to wildlife. Regional wildlife corridors provide foraging, breeding, and retreat areas for migrating, dispersing, immigrating, and emigrating wildlife populations. Local wildlife corridors provide access routes to food, cover, and water resources typically within restricted habitats available for use by resident wildlife species with restricted home ranges. Migrant birds that usually are adapted to higher levels of disturbance may also temporarily perch or feed in these restricted habitats.

The Green Island Road widening portion of the project site is approximately 0.8 miles in length and the limits of the road widening project extend approximately 35 feet north of the existing edge of Green Island Road. This existing road is a heavily trafficked route that does not provide a movement corridor for wildlife. Similarly, Jim Oswalt Way, Mezzetta Court, Commerce Boulevard, and Hanna Drive that would be rehabilitated, are fully developed areas with adjacent commercial businesses. No potential wildlife movement corridors would be affected by rehabilitating these streets. Consequently, there would be no impacts to regional or local wildlife corridors from implementation of the proposed project.

6. SPECIAL-STATUS SPECIES DEFINITION

6.1 Definitions
For purposes of this analysis, special-status species are plants and animals that are legally protected under the California and Federal Endangered Species Acts (CESA and FESA, respectively) or other regulations, and species that are considered rare by the scientific community (for example, the CNPS). Special-status species are defined as:
• plants and animals that are listed or proposed for listing as threatened or endangered under the CESA (Fish and Game Code §2050 et seq.; 14 CCR §670.1 et seq.) or the 1807
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
6 MONK & ASSOCIATES
FESA (50 CFR 17.12 for plants; 50 CFR 17.11 for animals; various notices in the Federal Register [FR] for proposed species);
• plants and animals that are candidates for possible future listing as threatened or endangered under the FESA (50 CFR 17; FR Vol. 64, No. 205, pages 57533-57547, October 25, 1999); and under the CESA (California Fish and Game Code §2068); • plants and animals that meet the definition of endangered, rare, or threatened under the CEQA (14 CCR §15380) that may include species not found on either CESA or FESA lists;
• Plants occurring on Ranks 1A, 1B, 2A, 2B, 3, and 4 of CNPS’ electronic Inventory (CNPS 2001). The CDFW recognizes that Ranks 1A, 1B, 2A and 2B of the CNPS inventory contain plants that, in the majority of cases, would qualify for State listing, and CDFW requests their inclusion in Environmental Impact Reports (EIRs). Plants occurring on CNPS Ranks 3 and 4 are "plants about which more information is necessary," and "plants of limited distribution," respectively (CNPS 2001). Such plants may be included as special-status species on a case by case basis due to local significance or recent biological information (more on CNPS Rank species below); • migratory nongame birds of management concern listed by USFWS (Migratory Nongame Birds of Management Concern in the United States: The list 1995; Office of Migratory Bird Management; Washington D.C.; Sept. 1995);
• animals that are designated as "species of special concern" by CDFW (2016); • Animal species that are “fully protected” in California (Fish and Game Codes 3511, 4700, 5050, and 5515).
• Bat Species that are designated on the Western Bat Working Group’s (WBWG) Regional Bat Species Priority Matrix as: “RED OR HIGH.” This priority is justified by the WBWG as follows: “Based on available information on distribution, status, ecology, and known threats, this designation should result in these bat species being considered the highest priority for funding, planning, and conservation actions. Information about status and threats to most species could result in effective conservation actions being implemented should a commitment to management exist. These species are imperiled or are at high risk of imperilment.”
In the paragraphs below, we provide further definitions of legal status as they pertain to the special-status species discussed in this report or in the attached tables.

Federal Endangered or Threatened Species. A species listed as Endangered or Threatened under the FESA is protected from unauthorized “take” (that is, harass, harm, pursue, hunt, shoot, trap) of that species. If it is necessary to take a federally-listed Endangered or Threatened species as 1808
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
7 MONK & ASSOCIATES
part of an otherwise lawful activity, it would be necessary to receive permission from the USFWS prior to initiating the take.

State Threatened Species. A species listed as Threatened under the CESA (§2050 of California Fish and Game Code) is protected from unauthorized “take” (that is, harass, pursue, hunt, shoot, trap) of that species. If it is necessary to “take” a state-listed Threatened species as part of an otherwise lawful activity, it would be necessary to receive permission from CDFW prior to initiating the “take.”
California Species of Special Concern. These are species in which their California breeding populations are seriously declining and extirpation from all or a portion of their range is possible.

This designation affords no legally mandated protection; however, pursuant to the CEQA Guidelines (14 CCR §15380), some species of special concern could be considered “rare.” Pursuant to its rarity status, any unmitigated impacts to rare species could be considered a “significant effect on the environment” (§15382). Thus, species of special concern must be considered in any project that will, or is currently, undergoing CEQA review, and/or that must obtain an environmental permit(s) from a public agency.

CNPS Rank Species. The CNPS maintains an “Inventory” of special-status plant species. This inventory has four lists of plants with varying rarity. These lists are: Rank 1, Rank 2, Rank 3, and Rank 4. Although plants on these lists have no formal legal protection (unless they are also state or federally-listed species), CDFW requests the inclusion of Rank 1 species in environmental documents. In addition, other state and local agencies may request the inclusion of species on other lists as well. The Rank 1 and 2 species are defined below:
• Rank 1A: Presumed extinct in California;
• Rank 1B: Rare, threatened, or endangered in California and elsewhere; • Rank 2A: Plants presumed extirpated in California, but more common elsewhere; • Rank 2B: Rare, threatened, or endangered in California, but more common elsewhere.

All of the plants constituting Rank 1B meet the definitions of Section 1901, Chapter 10 (Native Plant Protection Act) or Sections 2062 and 2067 (CESA) of the Fish and Game Code and are eligible for state listing (CNPS 2001). Rank 2 species are rare in California, but more common elsewhere. Ranks 3 and 4 contain species about which there is some concern and are reviewed by CDFW and maintained on “watch lists.”
Additionally, in 2006 CNPS updated their lists to include “threat code extensions” for each list.

For example, Rank 1B species would now be categorized as Rank 1B.1, Rank 1B.2, or Rank 1B.3. These threat codes are defined as follows:
• .1 is considered “seriously endangered in California (over 80% of occurrences threatened/high degree and immediacy of threat)”;
• .2 is “fairly endangered in California (20-80% of occurrences threatened)”; • .3 is “not very endangered in California (less than 20% of occurrences threatened or no current threats known).”
1809
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
8 MONK & ASSOCIATES
Under the CEQA review process only CNPS Rank 1 and 2 species are considered since these are the only CNPS species that meet CEQA’s definition of “rare” or “endangered.” Impacts to Rank 3 and 4 species are not regarded as significant pursuant to CEQA.

Fully Protected Birds. Fully protected birds, such as the white-tailed kite and golden eagle, are protected under California Fish and Game Code (§3511). Fully protected birds may not be “taken” or possessed (i.e., kept in captivity) at any time.

6.2 Potential Special-Status Plants on the Project Site Figure 5 provides a graphical illustration of the known records for special-status species within 3 miles of the project site and helps readers visually understand the number of sensitive species that occur in the vicinity of the project site. No special-status plants have been mapped on or adjacent the project site. However, according to the CNPS’ Inventory and CDFW’s CNDDB, a total of 14 special-status plant species are known to occur in the project site region (Table 3). No rare or listed plant species are expected to occur within the road widening project site. The limits of the project extend 35 feet north of the existing road shoulder into adjacent properties. This narrow strip of land is excessively disturbed and is dominated by ruderal vegetation.

Furthermore, M&A conducted monthly surveys in 2016 on the Giovannoni property that is located immediately to the north of the project site and is the largest area of undeveloped land north of the existing road; no special-status plants were identified on the Giovannoni property during the March through July 2016 surveys. Since the Giovannoni property is the only remaining natural, undisturbed habitat located in the vicinity of the project site, based on these survey results it can be concluded that there is no expectation that special-status plant species are present or would be impacted by the proposed project.

6.3 Potential Special-Status Animals in the Project Site Figure 5 provides a graphical illustration of the known records for special-status species within 3 miles of the project site and helps readers visually understand the number of sensitive species that occur in the vicinity of the project site. No special-status animal records have ever been mapped on or adjacent to the project site. However, a total of 16 special-status animal species are known to occur in the region of the project site (Table 4). None of these 16 species are expected to occur on the project site. However, because of the sensitivity of four (4) of the special-status animal species known to occur in the area we further discuss these species below. These species are vernal pool fairy shrimp (Branchinecta lynchi), California red-legged frog (Rana draytonii), northern harrier (Circus cyaneus), and Swainson’s hawk (Buteo swainsonii).

6.3.1 VERNAL POOL FAIRY SHRIMP
Vernal pool fairy shrimp was designated as threatened in its entire range on September 19, 1994 (Federal Register 59:48136-48153). Critical habitat for this species was designated on August 6, 2003. The closest CNDDB record for vernal pool fairy shrimp and the closest designated critical habitat of this vernal pool species is approximately 0.70 miles to the northwest of the project site (Figures 5 and 6).

The vernal pool fairy shrimp is a small aquatic crustacean that ranges in size from ½-inch to one inch long. Fairy shrimp feed on algae, bacteria, protozoa, rotifers and bits of detritus. The vernal 1810
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
9 MONK & ASSOCIATES
pool fairy shrimp occupies a variety of different vernal pool habitats, from small, clear, sandstone rock pools to large, turbid, alkaline, grassland valley floor pools. It tends to occur in smaller pools (less than 0.05-acre) that are most commonly found in grass or mud bottomed swales, or basalt flow depression pools in unplowed grasslands. It has also been collected in large vernal pools (e.g., 25 acres). Vernal pool fairy shrimp have been collected from early December to early May (USFWS 1994).

The female drops eggs to the pool bottom or the eggs remain in the brood sac until the mother dies and sinks. When the pool dries out, so do the eggs (known as cysts when dry). They remain in the dry pool bed until rains and other environmental stimuli hatch them. Cysts can withstand heat, cold and prolonged desiccation. When the pools refill, some, but not all, of the cysts may hatch. The cyst bank in the soil may contain cysts from several years of breeding. Average time to maturity is only forty-one days. In warmer pools, it can be as little as eighteen (Eriksen and Belk 1999).

The vernal pool fairy shrimp is widespread but not abundant. Known populations extend from Shasta County through most of the length of the Central Valley to Tulare County. Along the central coast, they range from northern Solano County to Pinnacles National Monument in San Benito County. Four additional, disjunct populations exist in Southern California. The ephemeral wetlands that support this network of populations are remnants of what was formerly a pristine vernal pool ecosystem, which has been converted to primarily agricultural and urban uses.

The project site does not provide potentially suitable habitat for the vernal pool fairy shrimp.

Furthermore, M&A conducted USFWS-approved wet and dry season surveys for vernal pool fairy shrimp on the adjacent Giovannoni property with negative findings. As such, M&A concludes that the project would not result in impacts to the vernal pool fairy shrimp or any other federally-listed fairy shrimp species. Consequently, there is no expectation that vernal pool fairy shrimp would be impacted by the proposed project. No mitigation is warranted for this species.

6.3.2 CALIFORNIA RED-LEGGED FROG
The California red-legged frog was federally-listed as threatened on May 23, 1996 (Federal Register 61: 25813-25833) and as such is protected pursuant to the FESA. On March 16, 2010 the USFWS issued the final designation for California red-legged frog Critical Habitat (USFWS 2010). The 2010 Critical Habitat maps (Federal Register dated March 17, 2010 (Volume 75, Number 51:12815-12864) show that the project site is located approximately 1.3 miles west of Critical Habitat Unit SOL-3 (Figure 6). The California red-legged frog is also a state “species of special concern.”
California “species of special concern” are species in which their California breeding populations are seriously declining and extirpation from all or a portion of their range is possible. This title affords no legally mandated protection for this species; however, pursuant to CEQA (14 CCR §15380), any project related impacts to this species would be regarded as significant.

California red-legged frogs are typically found in slow-flowing portions of perennial streams, and in intermittent streams, and hillside seeps that maintain pool environments or saturated soils 1811
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
10 MONK & ASSOCIATES
throughout the summer months. Riparian vegetation such as willows (Salix sp.) and emergent vegetation such as cattails are preferred red-legged frog habitats, though not necessary for this species to be present. This frog is also found in human-made ponds. Populations of the California red-legged frog will be reduced in size or eliminated from ponds supporting nonnative species such as bullfrogs (Lithobates catesbeiana), Centrarchid fish species (such as sunfish, blue gill, or largemouth bass), and signal and red swamp crayfish (Pacifastacus leniusculus and Procambarus clarkii, respectively), all known California red-legged frog predators.

The closest known record for the California red-legged frog is a 2008 sighting approximately

0.5-mile east of the project site in North Slough (CNDDB Occurrence No. 1062). This location is on the east side of Highway 29 and is not hydrologically connected to the project site. There are no California red-legged frog records on the west side of Highway 29. There is no perennial water or long-term inundation that occurs on or adjacent to the project site. The seasonal wetlands onsite are too shallow and seasonally inundated to provide habitat for this large native frog species which requires water most months of the year. Thus, it is improbable that the California red-legged frog would occur on the project site. Pursuant to CEQA, the proposed project would have no significant impacts on California red-legged frogs. No mitigation is warranted for this species.

6.3.3 NORTHERN HARRIER
The northern harrier is a state species of special concern. This raptor is also protected under California Fish and Game Code §3503.5 that protects nesting raptors and their eggs/young. The northern harrier is also protected from direct take under the Migratory Bird Treaty Act (50 CFR

10.13). Northern harriers build grass-lined nests on the ground within dense, low-lying vegetation in a variety of habitats, though they are typically found nesting in grassland or marsh habitats. They usually nest on level to near level ground. This species is particularly vulnerable to ground predators such as coyotes (Canis latrans), red fox (Vulpes vulpes), and various snake species. Ground nesting birds in general are also subject to disturbance by agricultural practices. Northern harriers likely forage over the project site; however, it would not likely nest in the narrow strips of land along Green Island Road. Pursuant to CEQA, the proposed project would have no significant impacts on northern harriers. No mitigation is warranted for this species.

6.3.4 SWAINSON’S HAWK
The Swainson's hawk is a state-listed threatened species afforded protection pursuant to the CESA. While it has no special federal status, it is protected from direct take under the Federal Migratory Bird Treaty Act of 1918 (16 U.S.C. 703-711). Swainson’s hawks, their nests, eggs, and young are also protected under California Fish and Game Code (§3503, §3503.5, §3513, and §3800). Finally, pursuant to CEQA, this hawk would be considered “rare” and impacts to its nest sites would be regarded as significant.

The Swainson’s hawk is generally a summer visitor to California. In the fall months, most Swainson’s hawks migrate to South America before returning to the United States to breed once again in the late spring. There is a small population of Swainson’s hawks that remain resident in California year-round. The nesting population of Swainson’s hawks in California was reduced considerably over historical nesting populations by the time it was afforded protections pursuant 1812
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
11 MONK & ASSOCIATES
to the CESA in 1984. Since that time, the nesting population of Swainson’s hawk has significantly recovered in California, as have other raptor species that were previously protected both as state and federally-listed species. Both the peregrine falcon (Falco peregrinus ssp. anatum) and the bald eagle (Haliaeetus leucocephalus) were similarly listed species under both the CESA and FESA but have both been delisted owing to population recovery. The Swainson’s hawk nesting population also likely has greatly recovered; however, owing to the absence of a thorough population census in California since the species was listed by the CDFW, it remains protected pursuant to the CESA.

The Swainson’s hawk inhabits open to semi-open areas at low to middle elevations in valleys, dry meadows, foothills, and level uplands (Kochert 1986). It nests almost exclusively in trees and will nest in almost any tree species that is at least 10 feet tall (Schmutz et. al. 1984). Nests are constructed in isolated trees that are dead or alive along drainages and in wetlands, or in windbreaks in fields and around farmsteads (Palmer 1988). Swainson’s hawks occasionally nest in shrubs, on telephone poles, and on the ground. In the Central Valley of California, the majority of Swainson's hawk nests and territories are associated with riparian systems and nests are commonly found in cottonwoods and oaks (Schlorff et. al. 1984). They have also been documented nesting in eucalyptus (Eucalyptus spp.), black walnut (Juglans hindsii), black locust (Robinia pseudoacacia), almond (Prunus dulcis), Osage orange (Maclura pomifera), Arizona cypress (Cupressus arizonica), and pine (Pinus spp.) (CNDDB records).

Foraging habitats include alfalfa fields, fallow fields, beet, tomato, and other low-growing row or field crops, dry-land and irrigated pasture, and rice land when not flooded (CDFG 1994). The Swainson's hawk generally forages in open habitats with short vegetation containing small mammals, reptiles, birds, and insects. Its primary prey in the Central Valley is California meadow vole (Microtus californicus). Agricultural areas are often preferred over more natural grassland habitats due to larger prey populations. In addition, agricultural practices (planting, maintenance, harvesting, disking) allow for access to prey, and very likely increases foraging success of Swainson’s hawks when farm equipment flushes prey during harvesting (observed many times by G. Monk). During the nesting season, Swainson’s hawks usually forage within two miles of their nests. Swainson’s hawk does not require habitats that contain many perches because it most often searches for prey aerially; therefore, it can occupy habitats with few or no perches except the nest tree (James 1992).

The closest known Swainson’s hawk record to the project site is approximately 2.4 miles north (CNDDB Occurrence No. 1717). There is no nesting habitat within the linear project site; however, eucalyptus trees that are located approximately 150 feet north of the project site provide potential nesting habitat. Using CDFW’s Swainson’s hawk survey guidelines (CDFG 2000), M&A biologist, Mr. Jesse Reebs, conducted a formal nesting survey for Swainson’s hawks in all potential habitats within one mile of the project site. No Swainson’s hawks or evidence of any raptor nesting was observed within a zone of influence of the project site during the Swainson’s hawk nesting surveys conducted in 2016 and 2017. However, because the Swainson’s hawk is a mobile species and could nest within a zone of influence of the proposed project, preconstruction surveys are necessary to ensure that the project will not impact this hawk. See the Impacts and Mitigations section for details. 1813
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
12 MONK & ASSOCIATES

7. REGULATORY FRAMEWORK FOR NATIVE WILDLIFE, FISH, AND PLANTS This section provides a discussion of those laws and regulations that are in place to protect native wildlife, fish, and plants. Under each law we discuss its relevance to the proposed project.

7.1 Federal Endangered Species Act
The FESA forms the basis for the federal protection of threatened or endangered plants, insects, fish and wildlife. FESA contains four main elements, they are as follows:

Section 4 (16 USCA §1533): Species listing, Critical Habitat Designation, and Recovery Planning: outlines the procedure for listing endangered plants and wildlife.

Section 7 (§1536): Federal Consultation Requirement: imposes limits on the actions of federal agencies that might impact listed species.

Section 9 (§1538): Prohibition on Take: prohibits the "taking" of a listed species by anyone, including private individuals, and State and local agencies.

Section 10: Exceptions to the Take Prohibition: non-federal agencies can obtain an incidental take permit through approval of a Habitat Conservation Plan (HCP).

In the case of salt water fish and other marine organisms, the requirements of FESA are enforced by NMFS. The USFWS enforces all other cases. Below, Sections 9, 7, and 10 of FESA are discussed since they are the sections most relevant to the proposed project.

Section 9 of FESA as amended, prohibits the "take" of any fish or wildlife species listed under FESA as endangered. Under Federal regulation, "take" of fish or wildlife species listed as threatened is also prohibited unless otherwise specifically authorized by regulation. "Take," as defined by FESA, means "to harass, harm, pursue, hunt, shoot, wound, kill, trap, capture, or collect, or to attempt to engage in any such conduct.” "Harm" includes not only the direct taking of a species itself, but the destruction or modification of the species' habitat resulting in the potential injury of the species. As such, "harm" is further defined to mean "an act which actually kills or injures wildlife; such an act may include significant habitat modification or degradation where it actually kills or injures wildlife by significantly impairing essential behavioral patterns, including breeding, feeding or sheltering" (50 CFR 17.3). A December 2001 decision by the 9th Circuit Court of Appeals (Arizona Cattle Growers’ Association, Jeff Menges, vs. the U.S. Fish and Wildlife Service and Bureau of Land Management, and the Southwest Center for Biological Diversity) ruled that the USFWS must show that a threatened or endangered species is present on a project site and that it would be taken by the project activities. According to this ruling, the USFWS can no longer require mitigation based on the probability that the species could use the site. Rather they must show that it is “reasonably certain to occur.” Section 9 applies to any person, corporation, federal agency, or any local or State agency. If "take" of a listed species (other than a plant species) is necessary to complete an otherwise lawful activity, this triggers the need to obtain an “incidental take permit” either through a Section 7 Consultation as discussed further below (for federal actions or private actions that are permitted 1814
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
13 MONK & ASSOCIATES
or funded by a federal agency such as the Corps), or through Section 10 of FESA which requires preparation of an HCP (for state and local agencies, or individuals, and projects without a federal “nexus”; for example, projects that do not need a Corps permit).

Section 7(a)(2) of the Act requires that each federal agency consult with the USFWS to ensure that any action authorized, funded or carried out by such agency is not likely to jeopardize the continued existence of an endangered or threatened species or result in the destruction or adverse modification of critical habitat for listed species. Critical habitat designations mean: (1) specific areas within a geographic region currently occupied by a listed species, on which are found those physical or biological features that are essential to the conservation of a listed species and that may require special management considerations or protection; and (2) specific areas outside the geographical area occupied by a listed species that are determined essential for the conservation of the species.

The Section 7 consultation process only applies to actions taken by federal agencies that are considering authorizing discretionary projects. Section 7 is by and between the NMFS and/or the USFWS and the federal agency contemplating a discretionary approval (that is, the federal “action agency,” for example, the Corps or the Federal Highway Administration). Private parties, cities, counties, etc. (i.e., applicants) may participate in the Section 7 consultation at the discretion of the federal agencies conducting the Section 7 consultation. The Section 7 consultation process is triggered by a determination of the “action agency” – that is, the federal agency that is carrying out, funding, or approving a project - that the project “may affect” a listed species or critical habitat. If an action is likely to adversely affect a listed species or designated critical habitat, formal consultation between the nexus agency and the USFWS/NMFS is required. As part of the formal consultation, the USFWS/NMFS may resolve any issues informally with the nexus agency or may prepare a formal Biological Opinion assessing whether the proposed action would be likely to result in “jeopardy” to a listed species or if it could adversely modify designated critical habitat. If the USFWS/NMFS prepares a Biological Opinion, it will contain either a “jeopardy” or “non-jeopardy” decision. If the USFWS/NMFS concludes that a proposed project would result in adverse modification of critical habitat or would jeopardize the continued existence of a federally-listed species (that is, it will issue a jeopardy decision), the nexus federal agency would be most unlikely to authorize its discretionary permit. If the USFWS/NMFS prepares a “non-jeopardy” Biological Opinion, the nexus federal agency may authorize the discretionary permit making all conditions of the Biological Opinion conditions of its discretionary permit. A non-jeopardy Biological Opinion constitutes an “incidental take” permit that allows applicants to “take” federally-listed species while otherwise carrying out legally sanctioned projects.

For non-federal entities, for example private parties, cities, and counties that are proposing a project that might result in incidental take, Section 10 provides the mechanism for obtaining that take authorization. Under Section 10 of FESA, for the applicant to obtain an "incidental take permit," the applicant is required to submit a "conservation plan" to the USFWS or NMFS that specifies the impacts that are likely to result to federally-listed species, and the measures the applicant will undertake to minimize and mitigate such impacts, and the funding that will be available to implement those steps. Conservation plans under FESA have come to be known as HCPs for short. The terms incidental take permit, Section 10 permit, and Section 10(a)(1)(B) 1815
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
14 MONK & ASSOCIATES
permit are used interchangeably by the USFWS. Section 10(a)(2)(B) of FESA provides statutory criteria that must be satisfied before an incidental take permit can be issued.

7.1.1 RESPONSIBLE AGENCY
FESA gives regulatory authority to the USFWS for federally-listed terrestrial species and nonanadromous fish. The NMFS has regulatory authority over federally-listed marine mammals and anadromous fish.

7.1.2 APPLICABILITY TO THE PROPOSED PROJECT
The project site does not have stream channels or drainages to support fish; hence, there would be no impacts to federally-listed fish. There is no expectation that federally-listed plants would occur within the project site boundaries. Furthermore, focused surveys for special-status plants have been conducted on the adjacent Giovannoni project site (which extends onto this project site) and no federally-listed plant species were identified; thus, there would be no project-related impacts to federally-listed plants (or any other special-status plant).

USFWS approved wet and dry season protocol surveys for federally-listed fairy shrimp species have been conducted on the adjacent Giovannoni project site and none were identified. There are no other federally-listed species issues relating to the project site. No impacts to federally listed species are expected from implementation of the proposed project. The project will have no significant effects on FESA-listed species.

7.2 Federal Migratory Bird Treaty Act
The Migratory Bird Treaty Act of 1918 (16 U.S.C. §§ 703-712, July 3, 1918, as amended 1936, 1960, 1968, 1969, 1974, 1978, 1986 and 1989) makes it unlawful to “take” (kill, harm, harass, shoot, etc.) any migratory bird listed in Title 50 of the Code of Federal Regulations, Section

10.13, including their nests, eggs, or young. Migratory birds include geese, ducks, shorebirds, raptors, songbirds, wading birds, seabirds, and passerine birds (such as warblers, flycatchers, swallows, etc.).

Executive Order 13186 for conservation of migratory birds (January 11, 2001) requires that any project with federal involvement address impacts of federal actions on migratory birds. The order is designed to assist federal agencies in their efforts to comply with the Migratory Bird TreatyAct and does not constitute any legal authorization to take migratory birds. The order also requires federal agencies to work with the USFWS to develop a memorandum of understanding (MOU). Protocols developed under the MOU must promote the conservation of migratory bird populations through the following means:
• avoid and minimize, to the extent practicable, adverse impacts on migratory bird resources when conducting agency actions;
• restore and enhance habitat of migratory birds, as practicable; and prevent or abate the pollution or detrimental alteration of the environment for the benefit of migratory birds, as practicable.
1816
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
15 MONK & ASSOCIATES

7.2.1 APPLICABILITY TO THE PROPOSED PROJECT
All raptors (birds of prey) and native song birds and wading birds are protected pursuant to the Migratory Bird Treaty Act. The Swainson’s hawk and various other tree nesting raptors (birds of prey) could nest in trees immediately adjacent to the project site and may be disturbed by grading activities or other earth work associated with the road construction project. In accordance with the Migratory Bird Treaty Act, as long as there is no direct mortality of species protected pursuant to this Act caused by development of the site, there should be no constraints to site development. To comply with the Migratory Bird Treaty Act, all active nest sites would have to be avoided while such birds were nesting. Upon completion of nesting, the project could commence as otherwise planned. Please review specific requirements for avoidance of nest sites for potentially occurring species in the Impacts and Mitigation section below.

7.3 California Endangered Species Act

7.3.1 SECTION 2081 OF THE CALIFORNIA ENDANGERED SPECIES ACT In 1984, the state legislated the CESA (Fish and Game Code §2050). The basic policy of CESA is to conserve and enhance endangered species and their habitats. State agencies will not approve private or public projects under their jurisdiction that would impact threatened or endangered species if reasonable and prudent alternatives are available. Because CESA does not have a provision for "harm" (see discussion of FESA, above), CDFW considerations pursuant to CESA are limited to those actions that would result in the direct take of a listed species.

If CDFW determines that a proposed project could impact a state-listed threatened or endangered species, CDFW will provide recommendations for "reasonable and prudent" project alternatives.

The CEQA lead agency can only approve a project if these alternatives are implemented, unless it finds that the project's benefits clearly outweigh the costs, reasonable mitigation measures are adopted, there has been no "irreversible or irretrievable" commitment of resources made in the interim, and the resulting project would not result in the extinction of the species. In addition, if there would be impacts to threatened or endangered species, the lead agency typically requires project applicants to demonstrate that they have acquired "incidental take" permits from CDFW and/or USFWS (if it is a federally-listed species) prior to allowing/permitting impacts to such species.

If proposed projects would result in impacts to a state-listed species, an "incidental take" permit pursuant to §2081 of the Fish and Game Code would be necessary (versus a Federal incidental take permit for federally-listed species). CDFW will issue an incidental take permit only if:
1) The authorized take is incidental to an otherwise lawful activity; 2) the impacts of the authorized take are minimized and fully mitigated; 3) measures required to minimize and fully mitigate the impacts of the authorized take:
a) are roughly proportional in extent to the impact of the taking on the species; b) maintain the project applicant’s objectives to the greatest extent possible; and, c) capable of successful implementation; and,
4) adequate funding is provided to implement the required minimization and mitigation measures and to monitor compliance with, and the effectiveness of, the measures. 1817
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
16 MONK & ASSOCIATES
If an applicant is preparing an HCP as part of the federal 10(a) permit process, the HCP might be incorporated into the §2081 permit if it meets the substantive criteria of §2081(b). To ensure that an HCP meets the mitigation and monitoring standards in Section 2081(b), an applicant should involve CDFW staff in development of the HCP. If a final Biological Opinion (federal action) has been issued for the project pursuant to Section 7 of the FESA, it might also be incorporated into the §2081 permit if it meets the standards of §2081(b).

No §2081 permit may authorize the take of a species for which the Legislature has imposed strict prohibitions on all forms of “take.” These species are listed in several statutes that identify “fully protected” species and “specified birds.” See Fish and Game Code §§ 3505, 3511, 4700, 5050, 5515, and 5517. If a project is planned in an area where a “fully protected” species or a “specified bird” occurs, an applicant must design the project to avoid all take.

Fish and Game Code §2080.1 allows an applicant who has obtained a “non-jeopardy” federal Biological Opinion pursuant to Section 7 of the FESA, or who has received a federal 10(a) permit (federal incidental take permit) pursuant to the FESA, to submit the federal opinion or permit to CDFW for a determination as to whether the federal document is “consistent” with CESA. If after 30 days CDFW determines that the federal incidental take permit is consistent with state law, and that all state-listed species under consideration have been considered in the federal Biological Opinion, then no further permit or consultation is required under CESA for the project. However, if CDFW determines that the federal opinion or permit is not consistent with CESA, or that there are state-listed species that were not considered in the federal Biological Opinion, then the applicant must apply for a state CESA permit under Section 2081(b). Section 2081(b) is of no use if an affected species is state-listed, but not federally-listed.

State and federal incidental take permits are issued on a discretionary basis and are typically only authorized if applicants are able to demonstrate that impacts to the listed species in question are unavoidable and can be mitigated to an extent that the reviewing agency can conclude that the proposed impacts would not jeopardize the continued existence of the listed species under review. Typically, if there would be impacts to a listed species, mitigation that includes habitat avoidance, preservation, and creation of endangered species habitat is necessary to demonstrate that projects would not threaten the continued existence of a species. In addition, management endowment fees are usually collected as part of the agreement for the incidental take permit(s).

The endowment is used to manage any lands set-aside to protect listed species, and for biological mitigation monitoring of these lands over (typically) a five-year period.

7.3.2 APPLICABILITY TO THE PROPOSED PROJECT
M&A biologists have conducted numerous surveys on the project site and the adjacent properties. During these multiple surveys, which spanned many months, no state-listed plant species were identified onsite. Thus, no impacts to state-listed plant species protected pursuant to the CESA will occur from the proposed project (Tables 3).

Swainson’s hawk is a state-listed threatened species. The closest known Swainson’s hawk record to the project site is approximately 2.4 miles north (CNDDB Occurrence No. 1717). There is no nesting habitat within the linear project site; however, eucalyptus trees that are located approximately 150 feet north of the project site provide potential nesting habitat. Using CDFW’s 1818
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
17 MONK & ASSOCIATES
Swainson’s hawk survey guidelines (CDFG 2000), M&A biologist, Mr. Reebs, conducted a formal nesting survey for Swainson’s hawks including all potential habitats within one mile of the project site. No Swainson’s hawks or evidence of any raptor nesting was observed within a zone of influence of the project site during the Swainson’s hawk nesting surveys conducted in 2016 and 2017. However, because the Swainson’s hawk is a mobile species and could nest within a zone of influence of the proposed project, preconstruction surveys are necessary to ensure that the project will not impact this hawk. See the Impacts and Mitigation section for details. There are no other state-listed animal species of concern on this project site.

7.4 California Fish and Game Code § 3503, 3503.5, 3511, and 3513 California Fish and Game Code §3503, 3503.5, 3511, and 3513 prohibit the “take, possession, or destruction of birds, their nests or eggs.” Disturbance that causes nest abandonment and/or loss of reproductive effort (killing or abandonment of eggs or young) is considered “take.” Such a take would also violate federal law protecting migratory birds (Migratory Bird Treaty Act).

All raptors (that is, hawks, eagles, owls) their nests, eggs, and young are protected under California Fish and Game Code (§3503.5). Additionally, “fully protected” birds, such as the white-tailed kite (Elanus leucurus) and golden eagle (Aquila chrysaetos), are protected under California Fish and Game Code (§3511). “Fully protected” birds may not be taken or possessed (that is, kept in captivity) at any time.

7.4.1 APPLICABILITY TO THE PROPOSED PROJECT
Raptors that may nest nearby and that could be impacted by the project include Swainson’s hawk, red-tailed hawk (Buteo jamaicensis), red-shouldered hawk (Buteo lineatus), and various owl species. Preconstruction surveys would have to be conducted for these species to ensure that there is no direct take of these birds or any other birds (song birds, wading birds) including their eggs, or young. Any active nests that were found during preconstruction surveys would have to be avoided by the project. Suitable non-disturbance buffers would have to be established around nest sites until the nesting cycle is complete. More specifics on the size of buffers are provided below in the Impacts and Mitigation section.

7.5 City of American Canyon General Plan
The City of American Canyon General Plan was adopted on November 3, 1994. It sets forth the following goals, objectives, and policies relevant to biological resources on the project site:

Goal 8: Protect and preserve the significant habitats, plants and wildlife that exist in the City and its Planning Area.

Objective 8.1: Maintain data and information regarding areas of significant biological value within the Planning Area to facilitate resource conservation and the appropriate management of development.

Policy 8.1.1: Acquire and maintain the most current information available regarding the status and location of sensitive biological elements (species and natural communities) within the City and, as appropriate, within the Sphere of Influence and Urban Limit Line. 1819
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
18 MONK & ASSOCIATES
Policy 8.1.4: Regularly monitor and review developments proposed within the City's Planning Area to assess their impacts on local biological resources and to recommend appropriate mitigation measures that the developer and/or government agency can implement.

Objective 8.2: Balance the preservation of natural habitat areas, including coastal saltmarsh, mixed hardwood forest, oak savannah, and wetland and riparian habitats, with new development in the City.

Policy 8.2.1: Land use applications for developments located within sensitive habitats, including coastal saltmarsh, mixed hardwood forest, oak savannah, and riparian habitats (see Figure 8-1 in the General Plan), or with areas potentially occupied by vernal pools (see Figure 8-2 in the General Plan) shall be accompanied by sufficient technical background data to enable an adequate assessment of the potential for impacts on these resources, and possible measures to reduce any identifiable impacts. In addition to examining Figure 8-1 in the General Plan for information on these sensitive habitats, an on-site assessment shall be conducted by a City approved qualified biologist to determine if sensitive habitats exist on-site. In instances where the potential for significant impacts exists, the applicant must submit a Biological Assessment Report prepared by a qualified professional.

Objective 8.3: Protect natural drainages and riparian corridors within the American Canyon Planning Area.

Policy 8.3.1: Review proposed developments in wetlands and riparian habitats to evaluate their conformance with the following policies and standards:
a. The development plan shall fully consider the nature of existing biological resources and all reasonable measures shall be taken to avoid significant impacts, including retention of sufficient natural open space and undeveloped buffer zones. b. Development shall be designed and sited to preserve watercourses, riparian habitat, vernal pools, and wetlands in their natural condition, unless these actions result in an unfeasible project, in which case habitat shall be replaced in accord with subsection "g" (below).
c. Where riparian corridors are retained, they shall be protected by an adequate buffer with a minimum 100-foot protection zone from the edge of the tree, shrub, or herb canopy (see policy 8.3.2).
d. Development shall incorporate habitat linkages (wildlife corridors) to adjacent open spaces, where appropriate and feasible.
e. Development shall incorporate fences, walls, vegetative cover, or other measures to adequately buffer habitat areas, linkages or corridors from built environment. f. Roads and utilities shall be located and designed such that conflicts with biological resources, habitat areas, linkages or corridors are avoided where feasible. g. Future development shall utilize appropriate open space or conservation easements in order to protect sensitive species or their habitats.
1820
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
19 MONK & ASSOCIATES
h. Future development shall mitigate unavoidable adverse impacts to waters of the United States, wetlands and riparian habitats (pursuant to the Federal Clean Water Act and the California Fish and Game Code, Section 1600 et seq.) by replacement on an in-kind basis. Furthermore, replacement shall be based on a ratio determined by the California Department of Fish and Game and/or Army Corps of Engineers in order to account for the potentially diminished habitat values of replacement habitat. Such replacement should occur on the original development site, whenever possible.

Alternatively, replacement can be effected, subject to state and federal regulatory approval, by creation or restoration of replacement habitats elsewhere (offsite but preferably within the City's Planning Area), protected in perpetuity by provision for an appropriate conservation easement or dedication.

Policy 8.3.6: Preserve and integrate the City's natural drainages in new development, as opposed to their channelization or undergrounding, emphasizing opportunities for the development of pedestrian paths and greenbelts along their lengths throughout the City.

Objective 8.4: Protect local vernal pools as well as the habitats of endangered species living within American Canyon's Planning Area.

Policy 8.4.1: Require that development plans incorporate all reasonable mitigation measures to avoid significantly impacting vernal pools for projects located within American Canyon's Planning Area.

Policy 8.4.3: Encourage activities that improve the biological value and integrity of the City's natural resources through vegetation restoration, control of alien plants and animals, and landscape buffering.

7.5.1 APPLICABILITY TO THE PROPOSED PROJECT
Consistent with General Plan Policies 8.1.1 and 8.1.4, this report represents a detailed assessment of the biological resources present on the project site and proposed impacts to these resources associated with development of the site. Proposed mitigation measures are detailed below in the project Impacts and Mitigation Measures section.

Consistent with General Plan Policy 8.2.1, the project site has been evaluated for presence of sensitive biological resources. This report represents the Biological Assessment Report documenting findings from M&A’s biological studies, and presents the current habitats and species present on the project site.

Consistent with Policies 8.3.1.a, 8.3.1.h, and 8.4.3, the applicant is proposing to mitigate the project’s proposed impacts to seasonal wetlands by creating wetlands and preserving these wetlands offsite at a nearby wetlands preserve. Mitigation would be at a 2:1 replacement to impacts ratio, or two times as much wetland would be created as impacted to compensate for wetland impacts. If offsite mitigation turns out to be infeasible, mitigation at the 2:1 replacement to impacts ratio may be met by purchasing wetland mitigation credits from a Corps and RWQCB 1821
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
20 MONK & ASSOCIATES
approved conservation bank. Any imposed conditions from regulatory permits issued that allow impacts to wetlands from the RWQCB or the Corps would also become conditions that must be met by the project to comply with the CEQA. If these regulatory agencies allow lower mitigation ratios through purchase of mitigation credits, the Corps/RWQCB approved ratios shall become the CEQA required mitigation ratios.

8. REGULATORY REQUIREMENTS PERTAINING TO WATERS OF THE UNITED

STATES AND STATE
This section presents an overview of the criteria used by the Corps, the RWQCB, the State Water Resources Control Board (SWRCB), and the CDFW to determine those areas within a project area that would be subject to their regulation.

8.1 U.S. Army Corps of Engineers Jurisdiction and General Permitting

8.1.1 SECTION 404 OF THE CLEAN WATER ACT
Congress enacted the Clean Water Act (CWA) “to restore and maintain the chemical, physical, and biological integrity of the Nation’s waters” (33 U.S.C. §1251(a)). Pursuant to Section 404 of the CWA (33 U.S.C. 1344), the Corps regulates the disposal of dredged or fill material into "waters of the United States" (33 CFR Parts 328 through 330). This requires project applicants to obtain authorization from the Corps prior to discharging dredged or fill materials into any water of the U.S.

In the Federal Register "waters of the United States" are defined as, “...all interstate waters including interstate wetlands...intrastate lakes, rivers, streams (including intermittent streams), wetlands, [and] natural ponds, the use, degradation or destruction of which could affect interstate or foreign commerce...” (33 CFR Section 328.3).

Limits of Corps’ jurisdiction:
(a) Territorial Seas. The limit of jurisdiction in the territorial seas is measured from the baseline in a seaward direction a distance of three nautical miles. (See 33 CFR 329.12) (b) Tidal Waters of the United States. The landward limits of jurisdiction in tidal waters:
(1) Extends to the high tide line, or
(2) When adjacent non-tidal waters of the United States are present, the jurisdiction extends to the limits identified in paragraph (c) of this section. (c) Non-Tidal Waters of the United States. The limits of jurisdiction in non-tidal waters:
(1) In the absence of adjacent wetlands, the jurisdiction extends to the ordinary high-water mark (OHWM), or
(2) When adjacent wetlands are present, the jurisdiction extends beyond the OHWM to the limit of the adjacent wetlands.
(3) When the water of the United States consists only of wetlands the jurisdiction extends to the limit of the wetland.
1822
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
21 MONK & ASSOCIATES
Section 404 jurisdiction in "other waters" such as lakes, ponds, and streams, extends to the upward limit of the OHWM or the upward extent of any adjacent wetland. The OHWM on a non-tidal water is:
• the "line on shore established by the fluctuations of water and indicated by physical characteristics such as a clear natural line impressed on the bank; shelving; changes in the character of soil; destruction of terrestrial vegetation; the presence of litter or debris; or other appropriate means that consider the characteristics of the surrounding areas" (33 CFR Section 328.3[e]).

Wetlands are defined as: “...those areas that are inundated or saturated by surface or ground water at a frequency and duration to support a prevalence of vegetation adapted for life in saturated soil conditions” (33 CFR Section 328.8 [b]). Wetlands usually must possess hydrophytic vegetation (i.e., plants adapted to inundated or saturated conditions), wetland hydrology (e.g., topographic low areas, exposed water tables, stream channels), and hydric soils (i.e., soils that are periodically or permanently saturated, inundated or flooded) to be regulated by the Corps pursuant to Section 404 of the CWA.

8.1.1.1 Clean Water Rule 2015
In 2015, the Environmental Protection Agency (EPA) and the Corps published the Clean Water Rule: Definition of ‘‘Waters of the United States’’; Final Rule which defines the scope of waters protected under the CWA. This Final Rule was published in light of the statute, science, Supreme Court decisions in U.S. v. Riverside Bayview Homes, Solid Waste Agency of Northern Cook County v. U.S. Army Corps of Engineers (SWANCC), and Rapanos v. United States (Rapanos), and the agencies’ experience and technical expertise. The Clean Water Rule (Rule) reflects consideration of the extensive public comments received on the proposed rule. The Rule was stayed in federal court shortly after it was adopted in 2015. In August 2018, the stay was lifted, and the Rule became effective once again and remains in effect today. The Rule ensures protection for the nation’s public health and aquatic resources and increases CWA program predictability and consistency by clarifying the scope of “waters of the United States” protected under the CWA.

The Rule only protects waters that have been historically covered by the CWA. A tributary, or upstream water, must show physical features of flowing water – a bed, bank, and OHWM – to warrant protection. The Rule provides protection for headwaters that have these features and have a significant connection to downstream waters. Adjacent waters are defined by three qualifying circumstances established by the Rule. These can include wetlands, ponds, impoundments, and lakes which can impact the chemical, biological or physical integrity of neighboring waters. All existing exclusions from longstanding agency practices are officially established for the first time. Waters used in normal agricultural, ranching, or silvicultural activities, as well as certain defined ditches, prior converted cropland, and waste treatment systems continue to be excluded from CWA protection.
1823
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
22 MONK & ASSOCIATES

8.1.1.2 Permitting Corps Jurisdictional Areas
To remain in compliance with Section 404 of the CWA, project proponents and property owners (applicants) are required to be permitted by the Corps prior to discharging or otherwise impacting waters of the U.S. In many cases, the Corps must visit a proposed project area (to conduct a “jurisdictional determination”) to confirm the extent of area falling under their jurisdiction prior to authorizing any permit for that project area. Typically, at the time the jurisdictional determination is conducted, applicants (or their representative) will discuss the appropriate permit application that would be filed with the Corps for permitting the proposed impact(s) to “waters of the United States.”
Pursuant to Section 404, the Corps normally provides two alternatives for permitting impacts to the type of waters of the U.S. found in the project area. The first alternative would be to use Nationwide Permit(s) (NWP). The second alternative is to apply to the Corps for an Individual Permit (33 CFR Section 235.5(2)(b)). The application process for Individual Permits is extensive and includes public interest review procedures (i.e., public notice and receipt of public comments) and must contain an “alternatives analysis” that is prepared pursuant to Section 404(b) of the CWA (33 U.S.C. 1344(b)). The alternatives analysis is also typically reviewed by the federal EPA and thus brings another resource agency into the permitting framework. Both the Corps and EPA take the initial viewpoint that there are practical alternatives to the proposed project if there would be impacts to waters of the U.S., and the proposed permitted action is not a water dependent project (e.g., a pier or a dredging project). Alternative analyses therefore must provide convincing reasons that the proposed permitted impacts are unavoidable. Individual Permits may be available for use in the event that discharges into regulated waters fail to meet conditions of NWP(s).

NWPs are a type of general permit administered by the Corps and issued on a nationwide basis that authorize minor activities that affect Corps regulated waters. Under NWP, if certain conditions are met, the specified activities can take place without the need for an individual or regional permit from the Corps (33 CFR, Section 235.5[c][2]). In order to use NWP(s), a project must meet 27 general nationwide permit conditions, and all specific conditions pertaining to the NWP being used (as presented at 33 CFR Section 330, Appendices A and C). It is also important to note that pursuant to 33 CFR Section 330.4(e), there may be special regional conditions or modifications to NWPs that could have relevance to individual proposed projects. Finally, pursuant to 33 CFR Section 330.6(a), Nationwide permittees may, and in some cases must, request from the Corps confirmation that an activity complies with the terms and conditions of the NWP intended for use (i.e., must receive “verification” from the Corps).

Prior to finalizing design plans, the applicant needs to be aware that the Corps maintains a policy of “no net loss” of wetlands (waters of the U.S.) from project area development. Therefore, it is incumbent upon applicants that propose to impact Corps regulated areas to submit a mitigation plan that demonstrates that impacted regulated areas would be recreated (i.e., impacts would be mitigated). Typically, the Corps requires mitigation to be “in-kind” (i.e., seasonal wetlands would be filled, mitigation would include seasonal wetland mitigation), and at a minimum of a 1:1 replacement ratio (i.e., one acre or fraction there of recreated for each acre or fraction thereof lost). Often a 2:1 replacement ratio is required if the Permittee is responsible for the mitigation. 1824
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
23 MONK & ASSOCIATES
In some cases, the Corps allows “out-of-kind” mitigation if the compensation site has greater value than the impacted site. Finally, there are many Corps approved wetland mitigation banks where wetland mitigation credits can be purchased by applicants to meet mitigation compensation requirements. Mitigation banks have defined service areas and the Corps may only allow their use when a project would have minimal impacts to wetlands.

8.1.2 APPLICABILITY TO THE PROPOSED PROJECT
On May 11, 2017, M&A biologists, Ms. Kingma and Mr. Jokerst, visited the project site to examine potential Corps regulated areas. M&A used the Corps’ 1987 Wetlands Delineation Manual (Corps 1987) in conjunction with the Regional Supplement for the Arid West Region (Corps 2008) to conduct this wetland delineation. A jurisdictional determination request and Draft Aquatic Resources Delineation Maps (Sheets 1-5) were prepared in compliance with the Corps’ 2016 Minimum Standards for Acceptance of Aquatic Resources Delineation Reports (Corps 2016).

Based on the draft Aquatic Resources Delineation Maps (Sheets 1-5, Attachment A), most of the potential wetlands and “other waters” within the project site have hydrologic connectivity to the Napa River via the storm drain system in Green Island Road. The Napa River is a traditional navigable water. Consequently, these potential seasonal wetlands and “other waters” identified within the project site would most likely be subject to Corps jurisdiction. In addition, the previously Corps-verified Jurisdictional Seasonal Wetland 1 (SW1) (Corps File No. 2007- 400829N) located on the 450 Green Island Road extends into the road widening project site.

Similarly, the previously Corps-verified jurisdictional Wetlands 27 and 33 (W27 and W33) (Corps File No. 2016-00309N) on the Giovannoni property also extend into the road widening project site (Sheet 4). The total area of previously verified jurisdictional wetlands within the road widening project site is 3,914 square feet (0.09-acre).

There are also some seasonal wetlands that are regarded as “isolated” since those wetlands do not have hydrologic connectivity to waters of the U.S./State. The potential wetland east/adjacent to 450 Green Island Road is mapped as an “isolated” seasonal wetland because it does not have hydrologic connectivity to any waters of the U.S. (Sheet 4). In addition, on the Giovannoni property, the previously Corps-verified “Isolated” Wetland 10 (IW10) (Corps File No. 2016- 00309N) extends into the road widening project site (Sheet 5). The total area of previously verified isolated wetlands within the road widening project site is 962 square feet (0.022-acre).

Isolated wetlands do not fall under the Corps’ jurisdiction but would be regulated by the RWQCB (see discussion in Section 8.2).

Sheets 2-5 indicate all areas on the project site that may be regulated as “waters of the U.S.” by the Corps. The total area of new potential wetlands mapped on the site is 0.018-acre and new potential linear wetlands is 0.002-acre. The total acreage of new potential “other waters” within the project site is 0.013-acre. M&A acknowledges that only the Corps can determine the actual acreage of “waters of the U.S.” pursuant to Section 404 of the Clean Water Act. In summary, if the Corps exerts their jurisdiction over all non-isolated water features mapped by M&A on the project site (this includes previously verified and newly delineated features), there is a total of 0.123-acre of waters of the U.S. on the project site.
1825
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
24 MONK & ASSOCIATES
Green Island Road widening will affect heretofore undeveloped surfaces that support ruderal and in some areas wetland habitats. In contrast Jim Oswalt Way, Mezzetta Court, Commerce Boulevard, and Hanna Drive are fully developed areas. Rehabilitation of these existing heavily used streets will not result in impacts to waters of the U.S. or State. It is assumed that all the features mapped along the northern shoulder of Green Island Road will be impacted by the proposed project since there is no alternative alignment to this road widening project. Thus, a total of 0.123-acre of waters of the U.S. will likely be impacted by the proposed project alongside Green Island Road. Prior to impacting jurisdictional waters of the U.S., the applicant must apply for authorization from the Corps. The proposed project would appear to qualify to use NWP 14 (Linear Transportation Projects) since the total impacts to waters of the U.S. are well below the 0.5-acre threshold and the project appears to meet all other conditions for use of this NWP. In addition, the project will impact 0.055-acre of “isolated” wetlands not subject to Corps jurisdiction (but subject to the RWQCB’s jurisdiction, see below).

The applicant is proposing to mitigate the project’s proposed impacts to waters of the U.S. by creating wetlands and preserving those wetlands at a nearby offsite wetlands preserve. Mitigation would be at a 2:1 replacement to impacts ratio, or two times as much wetland would be created as impacted to compensate for wetland impacts. If offsite mitigation turns out to be infeasible, the wetland mitigation requirement may be met by purchasing wetland mitigation credits from a Corps and RWQCB approved conservation bank. See the Impacts and Mitigations section for details.

8.2 California Regional Water Quality Control Board (RWQCB)

8.2.1 SECTION 401 OF THE CLEAN WATER ACT
The SWRCB and RWQCB regulate activities in "waters of the State" (which includes wetlands) through Section 401 of the CWA. While the Corps administers a permitting program that authorizes impacts to waters of the U.S., including wetlands and other waters, any Corps permit authorized for a proposed project would be inoperative unless it is a NWP that has been certified for use in California by the SWRCB, or if the RWQCB has issued a project specific certification of water quality. Certification of NWPs requires a finding by the SWRCB that the activities permitted by the NWP will not violate water quality standards individually or cumulatively over the term of the permit (the term is typically for five years). Certification must be consistent with the requirements of the federal CWA, the CEQA, the CESA, and the SWRCB’s mandate to protect beneficial uses of waters of the State. Any denied (i.e., not certified) NWPs, and all Individual Corps permits, would require a project specific RWQCB certification of water quality. Where a project will result in dredge or fill of non-federal waters of the State, the RWQCB will authorize those fills through waste discharge requirements issued under the Porter Cologne Water Quality Control Act.

On April 2, 2019, the SWRCB adopted a state-level definition of “wetlands,’ which definition is broader than the federal definition in that unvegetated areas may be considered a wetland water of the State. As a part of the same policy, the Water Board adopted permit procedures and standards governing the discharge of dredged or fill material into wetlands and other waters of the State. The policy includes, among other things, requirements for analyses to identify the least environmentally damaging practicable alternative (LEDPA) and compensatory mitigation standards including a 1826
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
25 MONK & ASSOCIATES
minimum 1:1 ratio for wetlands and streams, and full functional replacement of all waters on top of this minimum where applicable. The policy, which will govern both Section 401 certifications and WDRs, is scheduled to become effective nine months following the completion of review by the California Office of Administrative Law.

8.2.2 APPLICABILITY TO THE PROPOSED PROJECT
Any Section 404 permit authorized by the Corps for the project would be inoperative without also obtaining authorization from the RWQCB pursuant to Section 401 of the Clean Water Act (i.e., without obtaining a Clean Water Act Certification of Water Quality). Since the RWQCB does not have a formal method for technically defining what constitutes waters of the State, M&A expects that the RWQCB should remain consistent with the Corps’ determination.

Any impacts to waters of the State would have to be mitigated to the satisfaction of the RWQCB prior to the time this resource agency would issue a permit for impacts to such features. The RWQCB requirements for issuance of a “401 Permit” typically parallel the Corps requirements for permitting impacts to Corps regulated areas pursuant to Section 404 of the Clean Water Act.

Please refer to the Corps Applicability Section above for likely mitigation requirements for impacts to RWQCB regulated wetlands. Also, please refer to the applicability section of the Porter-Cologne Water Quality Control Act below for other applicable actions that may be imposed on the project by the RWQCB prior to the time any certification of water quality is authorized for the project. Please note that any isolated wetlands or other waters that are determined to be on the project site that are not regulated by the Corps pursuant to the SWANCC decision, would still be regulated by the RWQCB pursuant to the Porter-Cologne Water Quality Control Act and impacts to such features would also be required to be mitigated per RWQCB policies (see below). Impacts to waters of the State must be mitigated at a minimum 1:1 ratio or as otherwise determined by the RWQCB at the time a permit issued for the proposed project.

8.2.3 PORTER-COLOGNE WATER QUALITY CONTROL ACT
The uncontrolled discharge of pollutants into impaired water bodies is considered particularly detrimental. According to the EPA, sediment is one of the most widespread pollutants contaminating U.S. rivers and streams. Sediment runoff from construction sites is 10 to 20 times greater than from agricultural lands and 1,000 to 2,000 times greater than from forest lands (EPA 2005). Consequently, the discharge of storm water from large construction sites is regulated by the RWQCB under the federal CWA and California’s Porter-Cologne Water Quality Control Act.

The Porter-Cologne Water Quality Control Act, Water Code § 13260, requires that “any person discharging waste, or proposing to discharge waste, that could affect the waters of the State to file a report of discharge” with the RWQCB through an application for waste discharge (Water Code Section 13260(a)(1). The term “waters of the State” is defined as any surface water or groundwater, including saline waters, within the boundaries of the State (Water Code § 13050(e)). It should be noted that pursuant to the Porter-Cologne Water Quality Control Act, the RWQCB also regulates “isolated wetlands,” or those wetlands considered to be outside of the Corps’ jurisdiction pursuant to the SWANCC decision (see Corps Section above). 1827
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
26 MONK & ASSOCIATES
The RWQCB generally considers filling in waters of the State to constitute “pollution.” Pollution is defined as an alteration of the quality of the waters of the State by waste that unreasonably affects its beneficial uses (Water Code §13050(1)). The RWQCB litmus test for determining if a project should be regulated pursuant to the Porter-Cologne Water Quality Control Act is if the action could result in any “threat” to water quality.

The RWQCB requires complete pre- and post-development Best Management Practices Plan (BMPs) of any portion of the project site that is developed. This means that a water quality treatment plan for the pre- and post-developed project site must be prepared and implemented.

Preconstruction requirements must be consistent with the requirements of the National Pollutant Discharge Elimination System (NPDES). That is, a Storm Water Pollution Prevention Plan (SWPPP) must be developed prior to the time that a site is graded (see NPDES section below). In addition, a post construction BMPs plan, or a Storm Water Management Plan (SWMP) must be developed and incorporated into any site development plan.

8.2.4 APPLICABILITY TO THE PROPOSED PROJECT
The RWQCB has jurisdiction over both waters of the U.S./State (those waters with hydrologic connectivity to navigable waters- and thus, that are regulated pursuant to the Clean Water Act) and waters of the State (regulated via the CWA and the Porter-Cologne Water Quality Control Act). There is 0.055-acre of “isolated wetlands” not subject to Clean Water Act regulation shown on the wetland delineation maps (Sheets 1-5) alongside Green Island Road. While the Corps does not regulate impacts to isolated waters, the RWQCB has jurisdiction over isolated waters (waters include wetlands) pursuant to the Porter-Cologne Water Quality Control Act.

Accordingly, prior authorization from the RWQCB would be required prior to filling waters of the U.S./State (i.e., those waters subject to Clean Water Act jurisdiction) and waters of the State (which include isolated waters that are outside of the Corps’ Clean Water Act jurisdiction).

Additionally, since any “threat” to water quality can conceivably be regulated pursuant to the Porter-Cologne Water Quality Control Act, care will be required when constructing the proposed project to be sure that adequate pre-and post-construction BMPs are incorporated into the project implementation plans.

It should also be noted that prior to issuance of any permit from the RWQCB this agency will require submittal of a Notice of Determination from the City of American Canyon indicating that the proposed project has completed a review conducted pursuant to CEQA. The pertinent sections of the CEQA document (typically the biology section) are often submitted to the RWQCB for review prior to the time this agency will issue a permit for a proposed project.

9. STATE WATER RESOURCES CONTROL BOARD (SWRCB)/RWQCB – STORM

WATER MANAGEMENT

9.1 Construction General Permit
While federal CWA NPDES regulations allow two permitting options for construction related storm water discharges (individual permits and General Permits), the SWRCB has elected to adopt only one statewide Construction General Permit at this time that will apply to all storm water discharges associated with construction activity, except from those on Tribal Lands, in the 1828
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
27 MONK & ASSOCIATES
Lake Tahoe Hydrologic Unit, and those performed by the California Department of Transportation (CalTrans).

The Construction General Permit requires all dischargers where construction activity disturbs greater than one acre of land or those sites less than one acre that are part of a common plan of development or sale that disturbs more than one acre of land surface to:

1. Develop and implement a SWPPP which specifies BMPs that will prevent all construction pollutants from contacting storm water with the intent of keeping all products of erosion from moving off site into receiving waters.

2. Eliminate or reduce non-stormwater discharges to storm sewer systems and other waters of the nation. Achieve quantitatively-defined (i.e., numeric) pollutant-specific discharge standards, and conduct much more rigorous monitoring based on the project’s projected risk level.

3. Perform inspections of all BMPs.

This Construction General Permit is implemented and enforced by the nine RWQCBs. It is also enforceable through citizens’ suits and represents a dramatic shift in the State Water Board’s approach to regulating new and redevelopment sites, imposing new affirmative duties and fixed standards on builders and developers.

Types of Construction Activity Covered by the Construction General Permit • clearing,
• grading,
• disturbances to the ground such as stockpiling, or excavation that results in soil disturbances of at least one acre or more of total land area.

Construction activity that results in soil disturbances to a smaller area would still be subject to this General Permit if the construction activity is part of a larger common plan of development that encompasses greater than one acre of soil disturbance, or if there is significant water quality impairment resulting from the activity.

Construction activity does not include:
• routine maintenance to maintain original line and grade, • hydraulic capacity, or original purpose of the facility, • nor does it include emergency construction activities required to protect public health and safety.

The Construction General Permit includes several “post-construction” requirements. These requirements entail that site designs provide no net increase in overall site runoff and match preproject hydrology by maintaining runoff volume and drainage concentrations. To achieve the required results where impervious surfaces such as roofs and paved surfaces are being increased, 1829
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
28 MONK & ASSOCIATES
developers must implement non-structural off-setting BMPs, such as landform grading, site design BMPs, and distributed structural BMPs (bioretention cells, rain gardens, and rain cisterns). This “runoff reduction” approach is essentially a State Water Board-imposed regulatory requirement to implement Low Impact Development (“LID”) design features. Volume that cannot be addressed using non-structural BMPs must be captured in structural BMPs that are approved by the RWQCB.

Improving the quality of site runoff is necessary to improve water quality in impaired and threatened streams, rivers, and lakes (that is, water bodies on the EPA’s 303(d) list). The RWQCB prioritizes the water bodies on the 303(d) list according to potential impacts to beneficial uses. Beneficial uses can include a wide range of uses, such as nautical navigation; wildlife habitat; fish spawning and migration; commercial fishing, including shellfish harvesting; recreation, including swimming, surfing, fishing, boating, beachcombing, and more; water supply for domestic consumption or industrial processes; and groundwater recharge, among other uses. The State is required to develop action plans and establish Total Maximum Daily Loads (TMDLs) to improve water quality within these impaired water bodies. The TMDL is the quantity of a pollutant that can be safely assimilated by a water body without violating the applicable water quality standards.

Pursuant to the CWA, the RWQCB regulates construction discharges under the NPDES. The project sponsor of construction or other activities that disturb more than one acre of land must obtain coverage under NPDES Construction General Permit Order 2009-0009-DWQ, administered by the RWQCB1
.

9.1.1 APPLICABILITY TO THE PROPOSED PROJECT
To obtain coverage under the SWRCB administered Construction General Permit, the applicant (typically through its civil engineer) must electronically file a number of permit-related compliance documents (Permit Registration Documents (PRDs), including a Notice of Intent (NOI), a risk assessment, site map, signed certification, SWPPP, Notice of Termination (NOT), NAL exceedance reports, and other site-specific PRDs that may be required. The PRDs must be prepared by a Qualified SWPPP Practitioner (QSP) or Qualified SWPPP Developer (QSD) and filed by a Legally Responsible Person (LRP) on the RWQCB’s Storm Water Multi-Application Report Tracking System (SMARTS). (QSDs are typically civil engineers, professional hydrologists, engineering geologists, or landscape architects.) Once filed, these documents become immediately available to the public for review and comment. At a minimum, the SWPPP shall identify BMPs for implementation during project construction that are in accordance with the applicable guidance and procedures contained in the California Storm Water Quality Association’s California Stormwater Best Management Practices Handbook (2015).

1 CGP Order 2009-0009-DWQ remains in effect, but has been amended by CGP Order 2009-0014-DWQ, effective February 14, 2011, and CGP Order 2009-0016-DWQ, effective July 17, 2012. The first amendment merely provided additional clarification to Order 2009-0009-DWQ, while Order 2009-0016-DWQ eliminated numeric effluent limits on pH and turbidity (except in the case of active treatment systems), in response to a legal challenge to the original order.
1830
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
29 MONK & ASSOCIATES

9.2 RWQCB Municipal Storm Water Permitting Programs
The federal Clean Water Act (CWA) was amended in 1987 to address urban stormwater runoff pollution of the nation’s waters. In 1990, the U.S. Environmental Protection Agency (USEPA) promulgated rules establishing Phase 1 of the National Pollutant Discharge Elimination System (NPDES) stormwater program. The Phase 1 program for Municipal Separate Storm Sewer System (MS4s) requires operators that serve populations of 100,000 or greater to implement a stormwater management program to control polluted discharges from these MS4s. While Phase 1 of the municipal stormwater program has focused on large urban areas, Phase 2 of the municipal stormwater program was promulgated by the USEPA for smaller urban areas including nontraditional Small MS4s, which are governmental facilities such as military bases, public campuses, and prison and hospital complexes.

MS4 permits require the discharger (or dischargers that are permitted by the MS4 permittees) to develop and implement a Storm Water Management Plan/Program (SWMP) with the goal of reducing the discharge of pollutants to the maximum extent practicable (MEP). MEP is the performance standard specified in Section 402(p) of the Clean Water Act. The management programs specify what best management practices (BMPs) will be used to address certain program areas. The program areas include public education and outreach; illicit discharge detection and elimination; construction and post-construction; and good housekeeping for municipal operations. In general, medium and large municipalities are required to conduct chemical monitoring, though small municipalities are not.

9.2.1 NPDES C.3 REQUIREMENTS
The NPDES C.3 requirements went into effect for any project (public or private) that is “deemed complete” by the City or County (Lead Agency) on or after February 15, 2005, and which will result in the creation or replacement (other than normal maintenance) of at least 10,000 square feet of impervious surface area (roofs, streets, patios, parking lots, etc. Provision C.3 requires the onsite treatment of stormwater prior to its discharge into downstream receiving waters. Note that these requirements are in addition to the existing NPDES requirements for erosion and sedimentation controls during project construction that are typically addressed through acquisition of coverage under the SWRCB administered Construction General Permit. The C.3 requirements are typically required to be implemented by MS4 permittees (and their constituencies).

Projects subject to Provision C3 must include the capture and onsite treatment of all stormwater from the site prior to its discharge, including rainwater falling on building rooftops. Project applicants are required to implement appropriate source control and site design measures and to design and implement stormwater treatment measures in order to reduce the discharge of stormwater pollutants to the maximum extent practicable. While the Clean Water Act does not define “maximum extent practicable,” the Stormwater Quality Management Plans required as a condition of the municipal NPDES permits identify control measures (known as Best Management Plans, or BMPs) and, where applicable, performance standards, to establish the level of effort required to satisfy the maximum extent practicable criterion. It is ultimately up to the professional judgment of the reviewing municipal staff in the individual jurisdictions to determine whether a project’s proposed stormwater controls will satisfy the maximum extent 1831
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
30 MONK & ASSOCIATES
practicable criterion. However, there are numeric criteria used to ensure that treatment BMPs have been adequately sized to accommodate and treat a site’s stormwater. The C3 requirements are quite extensive, and their complete explanation is not provided here. However, the following are minimums that should be understood and adhered to:
• The applicant must provide a detailed and realistic site design and impervious surface area calculations. This site design and calculations will be used by the Lead Agency (County or City) to determine/verify the amount of impervious surface area that is being created or replaced. It should include all proposed buildings, roads, walkways, parking lots, landscape areas, etc., that are being created or redeveloped. If large (greater than 10,000 square feet) lots are being created an effort will need to be made to determine the total impervious surface area that could be created on that parcel. For example, if only a portion of the lot is shown as a “building envelope” then the lead agency will need to consider that a driveway will have to be constructed to access the envelope and that the envelope will then be developed as shown. If the C.3 thresholds are met (creation/redevelopment of 10,000 square feet of impervious surface area), a Stormwater Control Plan (SWCP) (if required by the Lead Agency, or whatever steps for compliance with Provision C3 are required locally) must accompany the application.
• If a SWCP is required by the Lead Agency for the project it must be stamped by a Licensed Civil Engineer, Architect, or Landscape Architect.

9.2.2 APPLICABILITY TO THE PROPOSED PROJECT
The City of American Canyon (the applicant) is an MS-4 permittee under the NPDES (see next section of this report). Accordingly, water quality compliance typically would fall to the City for implementation and compliance. However, as this project will likely require a Clean Water Act Section 401 permit, the RWQCB when considering issuance of the 401 permit, will require submittal of a SWMP that demonstrates that the constructed project will treat and hydromodify storm water falling on impervious surfaces.

9.3 California Department of Fish and Wildlife Protections

9.3.1 SECTION 1602 OF CALIFORNIA FISH AND GAME CODE
Pursuant to Section 1602 of the California Fish and Game Code: “An entity may not substantially divert or obstruct the natural flow of, or substantially change or use any material from the bed, channel, or bank of, any river, stream, or lake, or deposit or dispose of debris, waste, or other material containing crumbled, flaked, or ground pavement where it may pass into any river, stream, or lake, unless all of the following occur:
(1) CDFW receives written notification regarding the activity in the manner prescribed by CDFW. The notification shall include, but is not limited to, all of the following:
(A)A detailed description of the project’s location and a map. (B) The name, if any, of the river, stream, or lake affected. (C) A detailed project description, including, but not limited to, construction plans and drawings, if applicable.
1832
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
31 MONK & ASSOCIATES
(D)A copy of any document prepared pursuant to Division 13 (commencing with Section 21000) of the Public Resources Code.
(E) A copy of any other applicable local, state, or federal permit or agreement already issued.
(F) Any other information required by CDFW” (Fish & Game Code 2014).

Please see Section 1602 of the current California Fish and Game Code for further details.

Please also note that while not stated in the regulations above, CDFW typically considers its jurisdiction to include riparian vegetation (that is, the trees and bushes growing along the stream).

Thus, any proposed activity in a natural stream channel that would substantially adversely affect an existing fish and/or wildlife resource, including its riparian vegetation, would require entering into a Streambed Alteration Agreement (SBAA) with CDFW prior to commencing with work in the stream. However, prior to authorizing such permits, CDFW typically reviews an analysis of the expected biological impacts, any proposed mitigation plans that would be implemented to offset biological impacts and engineering and erosion control plans.

9.3.2 APPLICABILITY TO THE PROPOSED PROJECT
There are no drainages, tributaries, or any other areas within the project site that support a bed, bank, or channel and that would be regulated by the CDFW pursuant to Section 1602 of the California Fish and Game Code.

10. CALIFORNIA ENVIRONMENTAL QUALITY ACT (CEQA) REGULATIONS A CEQA lead agency must determine if a proposed activity constitutes a project requiring further review pursuant to the CEQA. Pursuant to CEQA, a lead agency would have to determine if there could be significant adverse impacts to the environment from a proposed project.

Typically, if within the city limits, the city would be the CEQA lead agency. If a discretionary permit (i.e., conditional use permit) would be required for a project (e.g. an occupancy permit must be issued), the lead agency typically must determine if there could be significant environmental impacts. This is usually accomplished by an “Initial Study.” If there could be significant environmental impacts, the lead agency must determine an appropriate level of environmental review prior to approving and/or otherwise permitting the impacts. In some cases, there are “Categorical Exemptions” that apply to the proposed activity; thus, the activity is exempt from CEQA. The Categorical Exemptions are provided in CEQA. There are also Statutory Exemptions in CEQA that must be investigated for any proposed project. If the project is not exempt from CEQA, the lowest level of review typically reserved for projects with no significant effects on the environment would be for the lead agency to prepare a “Mitigated Negative Declaration” (MND). If a proposed project would have only minimal impacts that can be mitigated to a level of no significance pursuant to the CEQA, then an MND is typically prepared by the lead agency. Finally, those projects that may have significant effects on the environment, or that have impacts that can’t be mitigated to a level considered less than significant pursuant to the CEQA, typically must be reviewed via an EIR. All CEQA review documents are subject to public circulation, and comment periods. 1833
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
32 MONK & ASSOCIATES
Section 15380 of CEQA defines “endangered” species as those whose survival and reproduction in the wild are in immediate jeopardy from one or more causes, including loss of habitat, change in habitat, overexploitation, predation, competition, disease, or other factors. “Rare” species are defined by CEQA as those who are in such low numbers that they could become endangered if their environment worsens; or the species is likely to become endangered within the foreseeable future throughout all or a significant portion of its range and may be considered “threatened” as that term is used in FESA. The CEQA Guidelines also state that a project will normally have a significant effect on the environment if it will “substantially affect a rare or endangered species of animal or plant or the habitat of the species.” The significance of impacts to a species under CEQA, therefore, must be based on analyzing actual rarity and threat of extinction to that species despite its legal status or lack thereof.

10.1.1 APPLICABILITY TO THE PROPOSED PROJECT
This report has been prepared as a Biology Section that is suitable for incorporation by the CEQA lead agency (the City of American Canyon) into the biology section of a CEQA review document such as an MND or EIR. This document addresses potential impacts to species that would be defined as endangered or rare pursuant to Section 15380 of the CEQA.

11. IMPACTS ANALYSIS
Below the criteria used in assessing impacts to Biological Resources is presented.

11.1 Significance Criteria
A significant impact is determined using CEQA and CEQA Guidelines. Pursuant to CEQA §21068, a significant effect on the environment means a substantial, or potentially substantial, adverse change in the environment. Pursuant to CEQA Guideline §15382, a significant effect on the environment is further defined as a substantial, or potentially substantial, adverse change in any of the physical conditions within the area affected by the project including land, air, water, minerals, flora, fauna, ambient noise, and objects of historical or aesthetic significance. Other Federal, State, and local agencies’ considerations and regulations are also used in the evaluation of significance of proposed actions.

Direct and indirect adverse impacts to biological resources are classified as “significant,” “potentially significant,” or “less than significant.” Biological resources are broken down into four categories: vegetation, wildlife, threatened and endangered species, and regulated “waters of the United States” and/or stream channels.

11.1.1 THRESHOLDS OF SIGNIFICANCE

11.1.1.1 Plants, Wildlife, Waters
In accordance with Appendix G (Environmental Checklist Form) of the CEQA Guidelines, implementing the project would have a significant biological impact if it would:
• Have a substantial adverse effect, either directly or through habitat modifications, on any species identified as a candidate, sensitive, or special-status species in local or regional plans, policies, or regulations, or by the CDFW or USFWS. 1834
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
33 MONK & ASSOCIATES
• Have a substantial adverse effect on any riparian habitat or other sensitive natural community identified in local or regional plans, policies, regulations or by the CDFW or USFWS.
• Have a substantial adverse effect on federally protected “wetlands” as defined by Section 404 of the CWA (including, but not limited to, marsh, vernal pool, coastal, etc.) through direct removal, filling, hydrological interruption, or other means. • Interfere substantially with the movement of any native resident or migratory fish or wildlife species or with established native resident or migratory wildlife corridors or impede the use of native wildlife nursery sites.
• Conflict with any local policies or ordinances protecting biological resources, such as a tree preservation policy or ordinance.
• Conflict with the provisions of an adopted HCP, Natural Community Conservation Plan, or other approved local, regional, or state HCP.

11.1.1.2 Waters of the United States and State.

Pursuant to Section 404 of the CWA (33 U.S.C. 1344), the Corps regulates the discharge of dredged or fill material into waters of the U.S., which includes wetlands, as discussed in the bulleted item above, and also includes “other waters” (stream channels, rivers) (33 CFR Parts 328 through 330). Substantial impacts to Corps regulated areas on a project site would be considered a significant adverse impact. Similarly, pursuant to Section 401 of the CWA, and to the Porter-Cologne Water Quality Control Act, the RWQCB regulates impacts to waters of the State. Thus, substantial impacts to RWQCB regulated areas on a project site would also be considered a significant adverse impact.

11.1.1.3 Stream Channels
Pursuant to Section 1602 of the California Fish and Game Code, CDFW regulates activities that divert, obstruct, or alter stream flow, or substantially modify the bed, channel, or bank of a stream which CDFW typically considers including riparian vegetation. Any proposed activity that would result in substantial modifications to a natural stream channel would be considered a significant adverse impact.

12. IMPACT ASSESSMENT AND PROPOSED MITIGATION
The Green Island Road widening will affect heretofore undeveloped surfaces that support ruderal and in some areas wetland habitats. These impacts associated with affected habitats along Green Island Road are addressed in detail below. In contrast, Jim Oswalt Way, Mezzetta Court, Commerce Boulevard, and Hanna Drive are fully developed areas. Rehabilitation of these existing heavily used streets will not result in biological impacts, or in impacts to trees, and thus it is concluded that there will be no biological impacts to sensitive resources from this rehabilitation.
1835
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
34 MONK & ASSOCIATES
Below we address potential impacts to sensitive biological resources including trees, waters of the United States and/or State and nesting birds, including the state listed threatened Swainson’s hawk. Each significant or potentially significant impact statement is followed with a mitigation prescription that when implemented would reduce impacts to the greatest extent possible. This impact analysis is based on engineering exhibits M&A received from the City of American Canyon.

12.1 Impact BIO-1. Proposed project could have a potentially significant impact on nesting Swainson’s hawk (Potentially Significant)
The Swainson’s hawk is a state listed threatened species. While the Swainson’s hawk has no special federal status, it is protected from direct take under the Federal Migratory Bird Treaty Act of 1918 (16 U.S.C. 703-711). Swainson’s hawks, their active nests, eggs, and young are also protected under California Fish and Game Code (§3503, §3503.5, §3513, and §3800). The closest known Swainson’s hawk record to the project site is approximately 2.4 miles north (CNDDB Occurrence No. 1717). There is no nesting habitat within the linear project site, however, the eucalyptus trees that are located approximately 150 feet north of the project site provide potential nesting habitat and preconstruction surveys would be necessary. If Swainson’s hawks are found to be nesting near the project site, implementation of the proposed project could be viewed by the CDFW as a project that could impact nesting Swainson’s hawks. Nest site disturbance which results in: (1) nest abandonment; (2) loss of young; (3) reduced health and vigor of eggs and/or nestlings (resulting in reduced survival rates); and (4) may ultimately result in the take (killing) of nestling or fledgling Swainson’s hawks incidental to otherwise lawful activities, would be considered a “take” by the CDFW. The taking of Swainson’s hawks in this manner can be viewed by the CDFW as a violation of Section 2080 of the California Fish and Game Code. This interpretation of take has been judicially affirmed by the landmark appellate court decision pertaining to CESA (Department v. ACID, 8 CA App. 4, 41554) (CDFW 1994).

Typically, the CDFW requires that any impact to a Swainson’s hawk nest be permitted through a Fish and Game Section 2081 management authorization. If an active nest is found on or adjacent to the project site within the area of influence of the project site (which is generally considered to be within 1,000 feet of the project site) “to avoid potential violation of Fish and Game Code 2080 (i.e., killing of listed species), project-related disturbance at active Swainson’s hawk nesting sites should be reduced or eliminated during critical phases of the nesting cycle (March 1- September 15 annually)” (CDFW 2000). If disturbance would occur, a Fish and Game Section 2081 management authorization would be required. Thus, preconstruction nesting surveys are warranted to ensure that the proposed project will not impact this hawk species. This impact could be mitigated to a less than significant level pursuant to CEQA.

12.2 Mitigation Measure BIO-1: Swainson’s Hawk
The CDFW has prepared guidelines for conducting surveys for Swainson’s hawk entitled:

Recommended Timing and Methodology for Swainson’s Hawk Nesting Surveys in California’s Central Valley (CDFW 2000). These survey recommendations were developed by the Swainson’s Hawk Technical Advisory Committee (TAC) to maximize the potential for locating nesting Swainson’s hawks, and thus reduce the potential for nest failures as a result of project activities and/or disturbances. To meet the CDFW’s recommendations for mitigation and 1836
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
35 MONK & ASSOCIATES
protection of Swainson’s hawks, surveys shall be conducted for a half-mile radius around all project activities and shall be completed for at least two survey periods immediately prior to a project’s initiation. The guidelines provide specific recommendations regarding the number of surveys based on when the project is scheduled to begin and the time of year the surveys are conducted.

If Swainson’s hawks are found to be nesting within 1,000 feet of the project site, the necessity of acquiring a Fish and Game Section 2081 management authorization shall be determined via consultation with the CDFW. Impacts to the nesting Swainson’s hawks shall not be allowed.

Accordingly, nest protection buffers shall be established that are a minimum of 300 feet from the nest site. If any nest is located within 1,000 feet of the project site, but that is not within the project limits, the 300-foot buffer shall only be established over the portion of the buffer that intersects the project limits. The nest site buffer shall be established in consultation with the CDFW or as required in any Fish and Game Section 2081 management authorization issued to the project by the CDFW. The nest protection buffer shall be maintained until the Swainson’s hawk nesting attempt is completed as determined by a qualified raptor biologist. Once the nesting cycle is complete, no further action is warranted for this raptor species unless CDFW has issued a Fish and Game Section 2081 management authorization that requires additional mitigation. Any mitigation required by a 2081 management authorization shall also become a condition of project approval.

Implementation of these mitigation measures would reduce impacts to nesting Swainson’s hawks to a level regarded as less than significant pursuant to the CEQA.

12.3 Impact BIO-2. Proposed project could have a potentially significant impact on Tree Nesting Raptors (excluding Swainson’s hawk which is discussed separately) (Potentially Significant)
Raptor (birds of prey) nests are protected pursuant to California Fish and Game Code (Sections 3503, 3503.5, 3513) and the Federal Migratory Bird Treaty Act. Suitable nesting habitat for white-tailed kite, red-shouldered hawk, red-tailed hawk and various owl species occurs near the project site. Potential impacts to these species from the proposed project include disturbance to nesting birds, and possibly death of adults and/or young. No nesting raptors have been identified on the project site; however, no specific surveys for nesting raptors have been conducted.

Additionally, raptors are highly mobile species and their nest locations may change from year to year. As such, in the absence of survey results, it must be concluded that impacts to nesting raptors from the proposed project would be potentially significant pursuant to CEQA. This impact could be mitigated to a level considered less than significant.

12.4 Mitigation Measure BIO-2: Tree Nesting Raptors
In order to avoid impacts to nesting raptors, nesting surveys should be conducted prior to commencing with construction work if this work would commence between February 1st and August 31st. The raptor nesting surveys should include examination of all trees within 300 feet of the entire project site.

If nesting raptors are identified during the surveys within 300 feet of the project site, a 300-foot radius around the nest tree should be fenced with orange construction fencing. If the nest tree is 1837
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
36 MONK & ASSOCIATES
located off the project site, then the buffer should be demarcated as per above, where the buffer intersects the project site. The size of the buffer may be altered if a qualified raptor biologist conducts behavioral observations and determines the nesting raptors are well acclimated to disturbance. If this occurs, the raptor biologist should prescribe a modified buffer that allows sufficient room to prevent undue disturbance/harassment to the nesting raptors. No construction or earth-moving activity should occur within the established buffer until it is determined by a qualified raptor biologist that the young have fledged (that is, left the nest) and have attained sufficient flight skills to avoid project construction zones. This typically occurs by July 15th.

This date may be earlier or later, and would have to be determined by a qualified raptor biologist.

If a qualified biologist is not hired to watch the nesting raptors then the buffers should be maintained in place through the month of August and work within the buffer can commence September 1st.

Any established nest protection buffer shall not be disturbed until follow-up nesting surveys are conducted and confirm that the nesting cycle is completed. In lieu of confirmation that the nesting cycle is complete, buffers may be removed on September 1. After buffers are removed, no further consideration is warranted for the inactive nest site(s) through February 1st. At this time, nesting surveys shall be completed once again if the proposed project would extend into the next nesting season.

This mitigation measure would reduce impacts to tree nesting raptors (with the exception of the Swainson’s hawk) to a level considered less than significant.

12.5 Impact BIO-3. Proposed project could have a potentially significant impact on Other Nesting Birds (Potentially Significant)
Nesting birds could be impacted by the proposed project. Birds and their nests are protected under California Fish and Game Code (Sections 3503, 3503.5, 3513), and the Migratory Bird Treaty Act. The ruderal herbaceous vegetation along the north side of Green Island Road is adjacent to a large wetland complex on the Giovannoni property that supports wading birds, shorebirds and waterfowl. Hence, the ruderal herbaceous vegetation along the north side of the road provides suitable nesting habitat for ground nesting birds. In addition, the trees along the road provide suitable nesting habitat for other common bird species. Birds are highly mobile species and their nest locations may change from year to year. In the absence of preconstruction nesting surveys, the proposed project may have a potentially significant impact on ground nesting birds. This impact could be mitigated to a less than significant level.

12.6 Mitigation Measure BIO-3: Other Nesting Birds
A nesting survey shall be conducted 15 days prior to earth moving or the commencement of construction work if this work would occur between February 1 and September 1 (the nesting season). If any birds are found nesting on the project site or within a zone of influence of the project site a 75-foot nest protection buffer shall be established around the nest(s). The buffer shall be staked with orange construction fencing. If special-status birds, such as tricolored blackbird (Agelaius tricolor) are found nesting or within a zone of influence of the project site a 300-foot protection buffer shall be established around the nesting site(s). If nesting birds are located within the zone of influence, but that are not within the project limits, the portions of the buffer(s) that intersect the project limits shall clearly be delineated as protected areas via the 1838
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
37 MONK & ASSOCIATES
placement of orange construction fencing. No construction or earth-moving activity shall occur within any nest protection buffer until the following conditions are met. The protective fencing shall remain in place until a qualified biologist determines that the nesting birds have completed their nesting cycle(s). If a qualified biologist does not make such a determination, then the buffers shall remain in place until September 1st. After buffers are removed, no further consideration is warranted for the inactive nest site(s) through February 1st. At this time, nesting surveys shall be completed once again if the proposed project would extend into the next nesting season.

Implementation of these mitigation measures would reduce the project’s impact to nesting birds to a level regarded as less than significant pursuant to CEQA.

12.7 Impact BIO-4. Proposed project will have a significant impact on Waters of the United States/ State (Significant)
The proposed project has been designed to reduce the total impacts to Corps and RWQCB jurisdictional waters to the maximum extent practicable. For example, the construction staging area has been relocated to the road rights-of-way to avoid impacting, even temporarily, additional natural area that may support waters of the United States/State. Yet under the proposed design there would still be minor impacts to waters of the United States/State. The proposed project will impact approximately 0.123 acre of waters of the U.S. In addition, the project will impact 0.055 acre of “isolated” wetlands subject to RWQCB jurisdiction. This impact or any minor impacts to waters of the U.S./State could be mitigated to a less than significant level pursuant to CEQA.

12.8 Mitigation Measure BIO-4: Waters of the United States/State The applicant must obtain a Clean Water Act Section 404 permit (i.e., authorization from the Corps to use NWP 14) from the U.S. Army Corps of Engineers in advance of impacts to waters of the United States. The proposed project appears to qualify to use NWP 14 (Linear Transportation Projects) since the total impacts to waters of the U.S. are well below the ½ acre threshold for use of this NWP and the project otherwise appears to meet all other conditions for use of NWP 14. In addition, the applicant must obtain a Clean Water Act Section 401 permit (i.e., “Water Quality Certification”) from the RWQCB for impacts to all Clean Water Act regulated waters (i.e., those waters also subject to the Corps’ Section 404 jurisdiction). In addition, the RWQCB must permit impacts to isolated waters that are outside of Clean Water Act jurisdiction. The RWQCB regulates impacts to isolated waters pursuant to the Porter- Cologne Water Quality Control Act and authorizes such impacts via issuance of Waste Discharge Requirements (WDRs). Water Quality Certification and issuance of WDRs are typically included in a single permitting loop with the RWQCB. Water Quality Certification and WDRs (as determined necessary by the RWQCB) must be obtained in advance of any impacts to waters of the State.

The Corps and the RWQCB require mitigation compensation as a condition of issuing permits to projects that fill/impact waters of the U.S./State. The applicant is proposing to mitigate impacts to 0.178-acre of jurisdictional waters of the U.S./State via creation and preservation of 0.36-acre of seasonal wetlands within a suitable offsite wetland habitat preserve. Typically, the Corps and 1839
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
38 MONK & ASSOCIATES
RWQCB require that impacted seasonal wetlands be replaced at a 2:1 replacement to impacts ratio, but this ratio can be dependent upon Mitigation Ratio Guidance provided by the Corps or RWQCB at the time of permit issuance.

If there are no suitable offsite areas to create and preserve waters of the United State/States, the purchase of mitigation credits from a Corps/RWQCB approved mitigation bank would also fully compensate for the project’s impacts to waters of the U.S./State. Any wetland compensation mitigation that is different than prescribed herein that is required by the Corps and/or RWQCB shall also become conditions of project approval enforceable by the City.

Implementation of these mitigation measures would reduce impacts to waters of the U.S./State to a level regarded as less than significant pursuant to CEQA.

1840
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
39 MONK & ASSOCIATES

13. LITERATURE CITED
Baldwin D.H, Goldman D.H., Keil D.J., Patterson R, Rosatti T.J., Wilken D.H. (ed.). 2012. The Jepson Manual Vascular Plants of California: Second Edition. University of California Press, Berkeley. 1568 pps.

Eriksen, C.H., and D. Belk. 1999. Fairy shrimps of California's puddles, pools, and playas, Mad River Press, Eureka, CA.

Beier, P. and S. Loe. 1992. "In my experience.." a checklist for evaluating impacts to wildlife movement corridors. Wildlife Society Bulletin Vol. 20(4): 6.

CDFG (California Department of Fish and Game). 1994. Staff report regarding mitigation for impacts to Swainson’s hawks (Buteo swainsonii) in the central valley of California. 14 pps. November 1, 1994.

CDFG (California Department of Fish and Game). 2000. Recommended Timing and Methodology for Swainson’s Hawk Nesting Surveys in California’s Central Valley. May 31, 2000. 4 pages.

CDFW. 2016. California Department of Fish and Wildlife. Complete List of Amphibian, Reptile, Bird and Mammal Species in California. Published September 2008; February 2011, May 2016 (updated).

City of American Canyon. 1994. General Plan for the City of American Canyon, adopted November 3, 1994.

CNDDB (California Natural Diversity Data Base). 2019. RareFind 5. Computer printout for special-status species within a 3-mile radius of the project site. California Natural Heritage Division, California Department of Fish and Wildlife, Sacramento, CA.

CNPS (California Native Plant Society). 2001. Inventory of rare and endangered plants of California (sixth edition). Rare plant scientific advisory committee, David P. Tibor, convening editor. California Native Plant Society. Sacramento, CA. x+338 pps.

Corps (U.S. Army Corps of Engineers). 1987. Corps of Engineers Wetlands Delineation Manual.

Technical Report, Y-87-1. US Army Engineer Waterways Experiment Station. Vicksburg, Mississippi. 100 pp.

Corps (U.S. Army Corps of Engineers). 2008. Regional Supplement to the U.S. Army Corps of Engineers Wetland Delineation Manual: Arid West Region (Version 2). Ed. J.S.

Wakeley, R.W. Lichvar, and C.V. Noble. ERDC/EL TR-06-16. Vicksburg, MS: U.S.

Army Engineer Research and Development Center. September 2008.

Environmental Laboratory. 1987. U.S. Army Corps of Engineers Wetlands Delineation Manual.

Department of the Army, Waterways Experiment Station, Vicksburg, MS. 1841
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
40 MONK & ASSOCIATES
Eriksen, C.H., and D. Belk. 1999. Fairy shrimps of California's puddles, pools, and playas, Mad River Press, Eureka, CA.

Estep, J.A. 1989. Biology, Movements, and Habitat Relationships of the Swainson’s Hawk in the Central Valley of California, 1986-87. State of California, The Resources Agency, Department of Fish and Game, Wildlife Management Division, Nongame Bird and Mammal Section. 52 pp.

Holland, V.L. & D.J. Keil. 1995. California vegetation. Kendall/Hunt Publishing Company.

James, P.C. 1992. Urban-nesting of Swainson's hawks in Saskatchewan. Condor. 94: 773-774.

Kochert, Michael N. 1986. Raptors. In: Cooperrider, Allan Y.; Boyd, Raymond J.; Stuart, Hanson R., eds. Inventory and monitoring of wildlife habitat. Denver, CO: U.S.

Department of the Interior, Bureau of Land Management, Denver Service Center: 313- 349.

NRCS (Natural Resource Conservation Service) 2017, United States Department of Agriculture.

Web Soil Survey. Available URL: http://websoilsurvey.sc.egov.usda.gov/app/ Palmer, Ralph S., editor. 1988. Handbook of North American birds. Volume 5. New Haven, CT:

Yale University Press. 463 p.

Schlorff, Ronald W. and Peter H. Bloom. 1984. Importance of riparian systems to nesting Swainson's hawks in the Central Valley of California. In: Warner, Richard E.; Hendrix, Kathleen M., eds. California riparian systems: Ecology, conservation, and productive management: Proceedings of a conference; 1981 September 17-19; Davis, CA. Berkeley, CA: University of California Press: 612-618.

Schmutz, Josef K.; Fyfe, Richard W.; Moore, David A.; Smith, Alan R. 1984. Artificial nests for ferruginous and Swainson's hawks. Journal of Wildlife Management. 48:1009-1013.

USFWS (U.S. Fish and Wildlife Service). 1994. Final Rule. Endangered and threatened wildlife and plants; determination of endangered status for the Conservancy fairy shrimp, longhorn fairy shrimp, and the vernal pool tadpole shrimp; and threatened status for the vernal pool fairy shrimp. Federal Register. September 19, 1994.

USFWS (U.S. Fish & Wildlife Service). 1996. Endangered and threatened wildlife and plants; determination of threatened status for the California red-legged frog. Final rule. Federal register: May 23, 1996 (Volume 61, Number 101).

USFWS (U.S. Fish & Wildlife Service). 2003. Final Critical Habitat for 15 Vernal Pool Species.

August 6, 2003.
1842
Biological Resources Analysis
Green Island Road Reconstruction and Widening Project
City of American Canyon, California
41 MONK & ASSOCIATES
USFWS (U.S. Fish & Wildlife Service). 2010. Endangered and Threatened Wildlife and Plants:

Revised Designation of Critical Habitat for California Red-Legged Frog; Final Rule.

Federal Register 50 CFR Part 17 March 17, 2010 (Volume 75, Number 51) Page 12815- 12864
1843
1844
1845
1846
1847
1848
1849
7DEOH
3ODQW6SHFLHV2EVHUYHGRQWKH*UHHQ,VODQG5RDG5HFRQVWUXFWLRQDQG:LGHQLQJ3URMHFW6LWH

MONK & ASSOCIATES
$QJLRVSHUPV'LFRWV
$SLDFHDH
*Ammi majus Greater ammi
Eryngium aristulatum var. aristulatum California coyote-thistle *Foeniculum vulgare Sweet fennel
$VWHUDFHDH
*Carduus pycnocephalus subsp. pycnocephalus Italian thistle *Helminthotheca echioides Bristly ox-tongue
Hemizonia congesta subsp. luzulifolia White hayfield tarweed *Matricaria discoidea Pineapple-weed
%RUDJLQDFHDH
Plagiobothrys undulatus Wavy-stemmed popcornflower
%UDVVLFDFHDH
*Brassica nigra Black mustard
*Raphanus sativus Wild radish
&KHQRSRGLDFHDH
*Atriplex prostrata Hastate orache
&RQYROYXODFHDH
*Convolvulus arvensis Bindweed
)DEDFHDH
*Medicago polymorpha California burclover
*HUDQLDFHDH
*Geranium dissectum Cut-leaf geranium
/\WKUDFHDH
*Lythrum hyssopifolia Hyssop loosestrife
0DOYDFHDH
*Malva parviflora Cheeseweed
0\UVLQDFHDH
*Lysimachia arvensis Scarlet pimpernel
3ODQWDJLQDFHDH
*Plantago lanceolata English plantain
3RO\JRQDFHDH
*Rumex conglomeratus Green dock
*Rumex crispus Curly dock
5DQXQFXODFHDH
*Ranunculus muricatus Spiny-fruit buttercup
5RVDFHDH
*Rubus armeniacus Himalayan blackberry
* Indicates a non-native species Page 1 of 2
1850
7DEOH
3ODQW6SHFLHV2EVHUYHGRQWKH*UHHQ,VODQG5RDG:LGHQLQJ3URMHFW6LWH

MONK & ASSOCIATES
$QJLRVSHUPV0RQRFRWV
$OLVPDWDFHDH
Alisma triviale Water plantain
&\SHUDFHDH
Eleocharis macrostachya Creeping spikerush
3RDFHDH
*Avena barbata Slender wild oat
*Bromus hordeaceus Soft chess
*Bromus madritensis subsp. madritensis Foxtail chess
Distichlis spicata Saltgrass
*Elymus caput-medusae Medusahead
Festuca idahoensis Idaho fescue
*Festuca perennis Italian ryegrass
*Hordeum marinum subsp. gussoneanum Mediterranean barley *Hordeum murinum subsp. leporinum Hare barley
*Phalaris aquatica Harding grass
*Polypogon monspeliensis Annual beard grass
* Indicates a non-native species Page 2 of 2
1851
7DEOH
:LOGOLIH6SHFLHV2EVHUYHGRQWKH*UHHQ,VODQG5RDG5HFRQVWUXFWLRQDQG:LGHQLQJ3URMHFW6LWH

MONK & ASSOCIATES
$PSKLELDQV
Sierran treefrog Pseudacris sierra
%LUGV
Turkey vulture Cathartes aura
Red-tailed hawk Buteo jamaicensis
American kestrel Falco sparverius
Eurasian collared-dove Streptopelia decaocto
Mourning dove Zenaida macroura
Black phoebe Sayornis nigricans
Western scrub jay Aphelocoma californica
American crow Corvus brachyrhynchos
Tree swallow Tachycineta bicolor
Cliff swallow Petrochelidon pyrrhonota
Barn swallow Hirundo rustica
Bushtit Psaltriparus minimus
Western bluebird Sialia mexicana
Northern mockingbird Mimus polyglottos
European starling Sturnus vulgaris
California towhee Pipilo crissalis
Red-winged blackbird Agelaius phoeniceus
Western meadowlark Sturnella neglecta
Brewer's blackbird Euphagus cyanocephalus
House finch Haemorhous mexicanus
Lesser goldfinch Spinus psaltria
House sparrow Passer domesticus
0DPPDOV
Botta's pocket gopher Thomomys bottae
Raccoon Procyon lotor
Feral cat Felis catus

Page 1 of 1 ends

1852
Habitat Probability on Project Site
Family
TaxonCommon Name Status* Flowering Period
7DEOH
6SHFLDO6WDWXV3ODQW6SHFLHV.QRZQWR2FFXULQWKH9LFLQLW\RIWKH*UHHQ,VODQG5RDG5HFRQVWUXFWLRQDQG:LGHQLQJ3URMHFW6LWH

MONK & ASSOCIATES
Area Locations
$SLDFHDH
Lilaeopsis masonii Fed: -
State: CRCNPS: Rank 1B.1
Marshes and swamps (brackish or freshwater); riparian scrub.

None. No suitable habitat along road shoulder. Highly disturbed. Mason's lilaeopsis April-October Closest record located 2.6 miles northwest of the project site (Occurrence No. 10) $VWHUDFHDH
Balsamorhiza macrolepis Fed: -
State: -CNPS: Rank 1B.2
Cismontane woodland; chaparral; valley and foothill grassland; [sometimes serpentinite]. 90 - 1555 meters None. No suitable habitat along road shoulder. Highly disturbed. Big-scale balsam-root March-June Closest record located 2.3 miles
southeast of the project site (Occurrence No. 7)
Lasthenia conjugens Fed: FE
State: -CNPS: Rank 1B.1
Valley and foothill grassland (mesic); vernal pools.

None. No suitable habitat along road shoulder. Highly disturbed. Contra Costa goldfields March-June CNPS one quad: Cuttings Wharf
3812223
Symphyotrichum lentum Fed: -
State: -CNPS: Rank 1B.2
Marshes and swamps (brackish and fresh water)
None. No suitable habitat along road shoulder. Highly disturbed. Suisun Marsh aster August-November Closest record located 1.4 miles northwest of the project site (Occurrence No. 128) &DPSDQXODFHDH
Downingia pusilla Fed: -
State: -CNPS: Rank 2.2
Valley and foothill grassland (mesic); vernal pools.

None. No suitable habitat along road shoulder. Highly disturbed. Dwarf downingia March-May Closest record located 2.6 miles north of the project site (Occurrence No. 108) Legenere limosa Fed: -
State: -CNPS: Rank 1B.1
Vernal pools. None. No suitable habitat along
road shoulder. Highly disturbed. Legenere April-June CNPS one quad: Cuttings Wharf 3812223

Page 1 of 3 ends

1853
Habitat Probability on Project Site
Family
TaxonCommon Name Status* Flowering Period
7DEOH
6SHFLDO6WDWXV3ODQW6SHFLHV.QRZQWR2FFXULQWKH9LFLQLW\RIWKH*UHHQ,VODQG5RDG:LGHQLQJ3URMHFW6LWH

MONK & ASSOCIATES
Area Locations
&KHQRSRGLDFHDH
Extriplex joaquinana Fed: -
State: -CNPS: Rank 1B.2
Chenopod scrub; meadows; valley and foothill grassland; [alkaline].

None. No suitable habitat along road shoulder. Highly disturbed. San Joaquin spearscale April-October Closest record located 2.2 miles south of the project site (Occurrence No. 58) &\SHUDFHDH
Carex lyngbyei Fed: -
State: -CNPS: Rank 2
Marshes or swamps (brackish or freshwater)
None. No suitable habitat along road shoulder. Highly disturbed. Lyngbye's sedge May-August Closest record located 1.6 miles northwest of the project site (Occurrence No. 28) )DEDFHDH
Astragalus tener tener Fed: -
State: -CNPS: Rank 1B.2
Playas; mesic grasslands (adobe clay), vernal pools (alkaline).

None. No suitable habitat along road shoulder. Highly disturbed. Alkali milkvetch March-June Closest record located 2.3 miles
south of the project site (Occurrence No. 50)
Lathyrus jepsonii jepsonii Fed: -
State: -CNPS: Rank 1B.2
Marshes and swamps (freshwater and brackish).

None. No suitable habitat along road shoulder. Highly disturbed. Delta tule pea May-September Closest record located 1.8 miles west of the project site (Occurrence No. 13) Trifolium amoenum Fed: FE
State: -CNPS: Rank 1B.1
Valley and foothill grassland (sometimes serpentinite)
None. No suitable habitat along road shoulder. Highly disturbed. Showy Indian clover April-June Closest record located 0.4 miles southeast of the project site (Occurrence No. 23) Trifolium hydrophilum Fed: -
State: -CNPS: Rank 1B.2
Marshes and swamps; valley and foothill grassland (mesic, alkaline); vernal pools. 0-300 m.

None. No suitable habitat along road shoulder. Highly disturbed. Saline clover April-June CNPS one quad: Cuttings Wharf 3812223

Page 2 of 3 ends

1854
Habitat Probability on Project Site
Family
TaxonCommon Name Status* Flowering Period
7DEOH
6SHFLDO6WDWXV3ODQW6SHFLHV.QRZQWR2FFXULQWKH9LFLQLW\RIWKH*UHHQ,VODQG5RDG:LGHQLQJ3URMHFW6LWH

MONK & ASSOCIATES
Area Locations
2UREDQFKDFHDH
Castilleja affinis neglecta Fed: FE
State: CTCNPS: Rank 1B.2
Valley and foothill grassland [serpentinite]
None. No suitable habitat along road shoulder. Highly disturbed. Tiburon paintbrush April-June Closest record located 2.3 miles southeast of the project site (Occurrence No. 5) Chloropyron molle molle Fed: FE
State: CRCNPS: Rank 1B.2
Marshes and swamps (coastal salt).

None. No suitable habitat along road shoulder. Highly disturbed. Soft salty bird's-beak July-September Closest record located 1.3 miles northwest of the project site (Occurrence No. 3) *StatusFederal:FE - Federal EndangeredFT - Federal ThreatenedFPE - Federal Proposed EndangeredFPT - Federal Proposed ThreatenedFC - Federal Candidate State:CE - California EndangeredCT - California ThreatenedCR - California RareCC - California CandidateCSC - California Species of Special Concern CNPS Continued:Rank 2 - Plants rare, threatened, or endangered in California, but more common elsewhereRank 2A - Extirpated in California, common elsewhereRank 2B.1 - Seriously endangered in California, but more common elsewhereRank 2B.2 - Fairly endangered in California, but more common elsewhereRank 2B.3 - Not very endangered in California, but more common elsewhereRank 3 - Plants about which we need more information (Review List)Rank 3.1 - Plants about which we need more information (Review List) Seriously endangered in CaliforniaRank 3.2 - Plants about which we need more information (Review List) Fairly endangered in CaliforniaRank 4 - Plants of limited distribution - a watch list CNPS:Rank 1A - Presumed extinct in CaliforniaRank 1B - Plants rare, threatened, or endangered in California and elsewhereRank 1B.1 - Seriously endangered in California (over 80% occurrences threatened/ high degree and immediacy of threat)Rank 1B.2 - Fairly endangered in California (20-80% occurrences threatened)Rank 1B.3 - Not very endangered in California (<20% of occurrences threatened or no current threats known)

Page 3 of 3 ends

1855
Closest Locations Probability on Project Site *Status Habitat 7DEOH
6SHFLDO6WDWXV$QLPDO6SHFLHV.QRZQWR2FFXULQWKH9LFLQLW\RIWKH*UHHQ,VODQG5RDG5HFRQVWUXFWLRQDQG:LGHQLQJ3URMHFW6LWH Species

MONK & ASSOCIATES
,QYHUWHEUDWHV
Branchinecta lynchi
Closest record located 0.7 miles north of the project site (Occurrence No. 232) None. Seasonal wetlands within road do not provide suitable habitat.

Fed: FTState: -
Endemic to the grasslands of the Central Valley, central coast mountains, and south coast mountains. Inhabit static rainfilled/vernal pools, small, clear water sandstone-depression pools and grassed swale, earth slump, or basalt-flow depression Vernal pool fairy shrimp
Other:
)LVK
Oncorhynchus mykiss irideus
Closest record located 0.9 miles south of the project site (Occurrence No. 4) in North Slough (tributary to Napa River) None. No rivers or streams. Fed: FT
State: -
From Russian River south to Soquel Creek, and to Pajaro River. Also found in San Francisco & San Pablo Bay Basins. Spawn in clear, cool, well oxygenated streams greater than 18 cm deep.

Steelhead - Central California Coast DPS
Other:

Spirinichus thaleichthys
Closest record located 1.5 miles west of the project site (Occurrence No. 26) in Napa River None. No rivers or streams. Fed: --
State: CT
Endemic to the Sacramento-San Joaquin River system. Inhabits open waters in the Delta and Suisun Bay. After spawning, larvae are carried downstream to brackish nursery areas.

Longfin smelt
Other:
$PSKLELDQV
Rana draytonii
Closest record located 0.5 miles east of the project site (Occurrence No. 1062) None. No suitable breeding/aquatic habitat and no migration habitat along road.

Fed: FTState: CSC
Occurs in lowlands and foothills in deeper pools and streams, usually with emergent wetland vegetation. Requires 11-20 weeks of permanent water for larval development.

California red-legged frog
Other:

Page 1 of 4 ends

1856
Closest Locations Probability on Project Site *Status Habitat 7DEOH
6SHFLDO6WDWXV$QLPDO6SHFLHV.QRZQWR2FFXULQWKH9LFLQLW\RIWKH*UHHQ,VODQG5RDG:LGHQLQJ3URMHFW6LWH Species

MONK & ASSOCIATES
5HSWLOHV
Actinemys marmorata marmorata
Closest record located 0.2 miles south of the project site (Occurrence No. 552) None. No suitable aquatic habitat. Fed: -
State: CSC
Inhabits ponds, marshes, rivers, streams, and irrigation ditches with aquatic vegetation. Needs suitable basking sites and upland habitat for egg laying. Occurs in the Central Valley and Contra Costa County.

Western pond turtle
Other:
%LUGV
Circus cyaneus
Closest record located 2.4 miles west of the project site (Occurrence No. 29) None. Unlikely to nest along road shoulder. Fed: -
State: CSC
Nests on the ground or in shrubby vegetation typically in grasslands, fallow farm lands, near freshwater and salt water marshes.

Northern harrier
Other:

Buteo swainsoni
Closest record located 2.4 miles north of the project site (Occurrence No. 1717) None. Unlikely to nest near project site. Preconstruction survey will be conducted.

Fed: -State: CT
Migratory and resident raptor that breeds in open areas with scattered trees. Prefers riparian and sparse oak woodland habitats for nesting. Requires nearby grasslands, grain fields, or alfalfa for foraging.

Swainson's hawk
Other:

Buteo regalis
Closest record located 1.2 miles north of the project site (Occurrence No. 28) None. Does not nest in California. Fed: --
State: WL
Winter migrant to California where they prefer grasslands, cultivated fields and arid areas with an abundance of prey species, such as pocket gophers, black-tailed hares, and cottontails.

Ferruginous hawk
Other:

Laterallus jamaicensis coturniculus
Closest record located 1.2 miles northwest of the project site (Occurrence No. 31) None. No marsh habitat in project area. Fed: --
State: CT
Inhabits salt marshes bordering larger bays. Prefers tidal salt marshes of pickleweed.

California black rail
Other:

Page 2 of 4 ends

1857
Closest Locations Probability on Project Site *Status Habitat 7DEOH
6SHFLDO6WDWXV$QLPDO6SHFLHV.QRZQWR2FFXULQWKH9LFLQLW\RIWKH*UHHQ,VODQG5RDG:LGHQLQJ3URMHFW6LWH Species

MONK & ASSOCIATES
Rallus obsoletus obsoletus
Closest record located 1.2 miles northwest of the project site (Occurrence No. 16) None. No marsh habitat in project area. Fed: FE
State: CE
Inhabits salt water and brackish marshes with tidal sloughs in San Francisco Bay. Prefers dense pickleweed for cover, but forages for invertebrates along mud-bottomed sloughs.

California Ridgway's rail
Other:

Charadrius alexandrinus nivosus
Closest record located 2.8 miles west of the project site (Occurrence No. 121) None. No nesting habitat in project area. Fed: FT
State: CSC
Prefers sandy beaches, salt pond levees, and shores of large alkali lakes. Requires sandy, gravelly, or friable soil for nesting.

Western snowy plover
Other:

Athene cunicularia hypugaea
Closest record located 2.2 miles north of the project site (Occurrence No. 935) None. Unlikely to nest along road shoulder. Fed: --
State: CSC
Found in open, dry annual or perennial grasslands, deserts and scrublands characterized by low-growing vegetation. Subterranean nester, dependent upon burrowing mammals, most notably, the California ground squirrel.

Western burrowing owl
Other:

Geothlypis trichas sinuosa
Closest record located 1.2 miles northwest of the project site (Occurrence No. 37) None. No nesting habitat in project area. Fed: -
State: CSC
Resident of freshwater and salt water marshes in the San Francisco Bay region. Requires thick, continuous cover for foraging and tall grasses, tules, or willows for nesting.

Salt marsh common yellowthroat
Other:

Melospiza melodia samuelis
Closest record located 2.0 miles northwest of the project site (Occurrence No. 16) None. No nesting habitat in project area. Fed: --
State: CSC
More properly known as Samuels Song Sparrow. Resident of salt marshes along the north side of San Francisco and San Pablo Bays. Inhabits tidal sloughs in the California marshes; nests in grindelia bordering slough channels.

San Pablo song sparrow
Other:

Agelaius tricolor
Closest record located 0.6 miles north of the project site (Occurrence No. 243) None. No nesting habitat in project area. Fed: -
State: CC
Colonial nester in dense cattails, tules, brambles or other dense vegetation. Requires open water, dense vegetation, and open grassy areas for foraging.

Tricolored blackbird
Other: CSC

Page 3 of 4 ends

1858
Closest Locations Probability on Project Site *Status Habitat 7DEOH
6SHFLDO6WDWXV$QLPDO6SHFLHV.QRZQWR2FFXULQWKH9LFLQLW\RIWKH*UHHQ,VODQG5RDG:LGHQLQJ3URMHFW6LWH Species

MONK & ASSOCIATES
0DPPDOV
Reithrodontomys raviventris
Closest record located 1.2 miles northwest of the project site (Occurrence No. 48) None. No marsh habitat in project area. Fed: FE
State: CE
Inhabits saline marshes in the San Francisco Estuary. Prefers pickleweed marshes. Requires higher areas for escaping high water.

Salt marsh harvest mouse
Other:
*StatusFederal:FE - Federal EndangeredFT - Federal ThreatenedFPE - Federal Proposed EndangeredFPT - Federal Proposed ThreatenedFC - Federal CandidateFPD - Federally Proposed for delisting State:CE - California EndangeredCT - California ThreatenedCR - California RareCC - California CandidateCSC - California Species of Special ConcernFP - Fully ProtectedWL - Watch List. Not protected pursuant to CEQA

Page 4 of 4 ends

1859
Table A: Tree Survey Data– Green Island Road Reconstruction and Widening Project Site
Tag
Number Tree Species # of Stems DBH (inches) Health (0-5) 3919 Unknown 4 8.7, 6.5, 4.0, 4.5 3
3920 Pyrus calleryana 11 3.0, (3) 2.0, 1.5, (5) 1.0, 0.5 4 3921 Sequoia sempervirens 1 22.3 4
3922 Sequoia sempervirens 1 21.7 4
3923 Sequoia sempervirens 1 33.6 4
3924 Sequoia sempervirens 1 16.7 4
3925 Sequoia sempervirens 1 27.0 4
3926 Sequoia sempervirens 1 34.3 4
3927 Sequoia sempervirens 1 33.2 4
3928 Sequoia sempervirens 1 17.6 3
3929 Sequoia sempervirens 1 28.0 4
3930 Sequoia sempervirens 1 30.0 4
3931 Sequoia sempervirens 1 7.7 4
3932 Sequoia sempervirens 1 23.2 4
3933 Sequoia sempervirens 1 21.0 4
3934 Sequoia sempervirens 1 21.0 4
3935 Sequoia sempervirens 1 31.0 4
3936 Sequoia sempervirens 1 30.0 4
3937 Sequoia sempervirens 1 24.0 3
3938 Sequoia sempervirens 1 18.0 3
3939 Quercus agrifolia agrifolia 6 1.5, (2) 3.0,6.0,4.0,2.0 4 3940 Quercus agrifolia agrifolia 5 4.0, (2) 3.0, 2.0, 1.0 4 3941 Quercus agrifolia agrifolia 1 15.0 5
3942 Quercus agrifolia agrifolia 2 10.0, 5.0 5
3943 Quercus agrifolia agrifolia 8 6.0,3.0,(4) 4.0, 2.0, 1.0 5 3944 Quercus agrifolia agrifolia 6 4.0, 4.5, 7.0, (3) 2.0 5 3945 Quercus agrifolia agrifolia 4 5.9, 6.0, 4.0, 2.0 4 3946 Quercus agrifolia agrifolia 6 6.8, 6.7, 4.0, (3) 1.0 4 3947 Quercus kelloggii 1 7.9 4
3948 Quercus agrifolia agrifolia 16 (2) 4.0, 3.5, 3.0, (3) 2.0, 1.5, (8)

1.0 4
3949 Quercus agrifolia agrifolia 1 11.5 5
3950 Quercus kelloggii 1 10.5 4
3951 Quercus agrifolia agrifolia 7 3.5,3.0,2.0,1.0,1.0,1.0,2.0 5 3952 Quercus agrifolia agrifolia 3 6.3, 11.0, 10.0 5
3953 Pyrus calleryana 1 10.2 4
3954 Quercus agrifolia agrifolia 1 5.4 5
3955 Populus fremontii fremontii 2 20.1, 5.6 4
3956 Populus fremontii fremontii 1 22.0 4
3957 Quercus chrysolepis 1 11.2 4
3958 Sequoia sempervirens 1 20.4 1
1860
Tag
Number Tree Species # of Stems DBH (inches) Health (0-5) 3959 Sequoia sempervirens 1 17.4 0
3960 Sequoia sempervirens 1 13.5 2
3961 Sequoia sempervirens 1 20.5 2
3962 Sequoia sempervirens 1 17.1 3
3963 Sequoia sempervirens 1 22.4 0
3964 Sequoia sempervirens 1 26.0 0
3965 Sequoia sempervirens 1 24.7 0
3966 Sequoia sempervirens 1 24.4 0
3967 Sequoia sempervirens 1 16.2 0
3968 Sequoia sempervirens 1 21.7 4
3969 Sequoia sempervirens 1 18.5 1
3970 Sequoia sempervirens 1 18.3 2
3971 Prunas Sp. 1 19 0
3972 Sequoia sempervirens 1 18.7 4
3973 Sequoia sempervirens 1 20.1 4
3974 Sequoia sempervirens 1 19.7 4
3975 Befula nigra 1 15.1 0
3976 Sequoia sempervirens 1 20.0 4
3977 Prunas Sp. 1 11.2 0
3978 Sequoia sempervirens 1 20.0 4
3979 Sequoia sempervirens 1 19.5 4
3980 Sequoia sempervirens 1 22.0 4
3981 Unknown 1 9.0 0
3982 Prunas Sp. 1 20.3 0
3983 Phoenix canariensis 1 41.2 4
3984 Sequoia sempervirens 1 21.4 4
3985 Prunas Sp. 1 22.0 0
3986 Prunas Sp. 1 24.0 0
3987 Sequoia sempervirens 1 21.2 4
3988 Sequoia sempervirens 1 16.3 4
3989 Sequoia sempervirens 1 12.3 4
3990 Quercus lobata 1 25.1 4
3991 Sequoia sempervirens 1 11.0 3
3992 Sequoia sempervirens 1 21.0 2
3993 Sequoia sempervirens 1 23.0 1
3994 Sequoia sempervirens 1 29.0 5
3995 Sequoia sempervirens 1 26.0 3
3996 Sequoia sempervirens 1 28.0 5
3997 Sequoia sempervirens 1 23.5 5
3998 Sequoia sempervirens 1 24.5 5
3999 Morus alba 3 11.5, 4.0, 3.5 5
4000 Morus alba 1 8.25 4
XXXX Fraxinus oxycarpa 1 3.3 3
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
City of American Canyon—Giovannoni Logistics Center Project Draft EIR
FirstCarbon Solutions
C.8 - Jennings 2021 California Red-legged Frog Habitat Assessment C-605
1872

THIS PAGE INTENTIONALLY LEFT BLANK
1873

HABITAT ASSESSMENT

FOR THE CALIFORNIA RED-LEGGED FROG,

AT THE PROPOSED GIOVANNONI LOGISTICS PROJECT SITE,

AMERICAN CANYON, NAPA COUNTY, CALIFORNIA
March 11, 2021
Prepared for:

Robert F. Perrera
The Huffman-Broadway Group, Inc.
828 Mission Street
San Rafael, CA 94901
Prepared by:

Mark Jennings
Rana Resources
P.O. Box 2185
Davis, CA 95617-2185
1874

TABLE OF CONTENTS
SUMMARY ....................................................................................................................... 1

1.0 INTRODUCTION ................................................................................................. 1

2.0 PROJECT DESCRIPTION AND SETTING ..................................................... 1

3.0 METHODS ............................................................................................................ 4

4.0 RESULTS AND DISCUSSION ........................................................................... 4

5.0 CONCLUSIONS ................................................................................................... 5

6.0 REFERENCES ...................................................................................................... 6

7.0 APPENDIX ............................................................................................................ 8 California Red-Legged Frog Habitat Assessment Form..........................................8

FIGURES
Figure 1. Location of 210-acre Giovannoni parcel at within the City of American Canyon....3 Figure 2. Location of the 210-acre Giovannoni parcel in American Canyon showing surrounding infrastructure and development ……………………………..……4 Figure 3. Locations of CRLF within 3.1 miles of the southeast corner of the Project site.......6 1875
1 SUMMARY
This report is a Habitat Assessment for the federally threatened California red-legged frog (Rana draytonii, hereafter CRLF) at the location of the approximately 210-acre infill development [=Giovannoni Logistics Project] between Devlin Road to the north and Green Island Road to the south in the northwestern part of the City of American Canyon, Napa County (Project). The Project is now nearly entirely surrounded by industrial businesses and warehouse buildings, along with other structures, as well as Southern Pacific Railroad tracks to the south and east, and Highway 29 to the east. The Napa River estuary lies further to the west.

The Project site consists of an open field with a mosaic non-native annual grasses and seasonal wetlands. It is subject to sheet flooding which eventually drains northwest into an unnamed channel which continues off-site under Devlin Road. There are no connections with other stream courses which drain the agricultural fields and hills east of Highway 29. The area is relatively flat with an elevational range of approximately 20-50 feet.

The closest known CRLF records to the site are 0.6-2.4 miles to the east and southeast; additional CRLF records 3.7 miles and further away lie within Critical Habitat designated for this species (SOL-2 and SOL-3). All of these records lie east of Highway 29 which is a major barrier to any potential movements of CRLF to the west due to continuous traffic, highway berms, and the re-routing of drainages into culverts under the freeway. Additionally, the Project is completely isolated from all areas to the east by Highway 29, railroads, buildings, and other urban infrastructure, and there are no hydrologic connections with any stream channels off-site to the east of Highway 29. Finally, there is no suitable breeding or rearing habitat for CRLF on site due to the shallow and ephemeral nature of the seasonal wetlands and the lack of any suitable riparian vegetation for cover. Thus, it is my professional opinion that the Project site lacks habitat for this species and that CRLF cannot access the site from surrounding occupied habitats to the east and southeast.

1.0 INTRODUCTION
A proposed development for 6 warehouse and office buildings on the Giovannoni Parcel within the northwest portion of the City of American Canyon, Napa County, California, has been proposed (Figure 1). Since the 210-acre site lies within the historic range for the California redlegged frog (Rana draytonii, hereafter CRLF) [Stebbins 2003], and is near occupied Critical Habitat for CRLF (USFWS 2010), a habitat assessment was conducted for this species.

2.0 PROJECT DESCRIPTION AND SETTING
The 210-acre project site is located between Devlin Road to the north and Green Island Road to the south in the northwestern part of American Canyon, Napa County (Project) [Figure 1]. The Project is now nearly entirely surrounded by industrial businesses and warehouse buildings, 1876
2 Figure 1. Location of 210-acre Giovannoni parcel within the City of American Canyon. along with other structures, as well as Southern Pacific Railroad tracks to the south and east, and Highway 29 to the east (Figure 2). The Napa River estuary lies further to the west. 1877
3 Figure 2. Location of the 210-acre Giovannoni parcel in American Canyon showing surrounding infrastructure and development. Google Earth photograph taken in 2020.

The Project site consists of an open field with a mosaic non-native annual grasses and seasonal wetlands that has used for cattle (Bos taurus) grazing. It is subject to sheet flooding which eventually drains northwest into an unnamed channel which continues off-site under Devlin Road and eventually drains into the Napa River estuary. There are no connections with other stream courses which drain the agricultural fields and hills east of Highway 29. The area is relatively flat with an elevational range of approximately 20-50 feet.

The Project site has been previously surveyed and mapped for wetlands by Monk and Associates (2018). They also conducted surveys for special status plants and animals, including CRLF on a small portion of the site (for the Devlin Road and Napa Valley Vine Trail Project). All of the wetlands were determined to be shallow and seasonal, with inundation limited to only about 3-4 months during the year after sufficient winter and spring rainfall.

There are no trees or dense riparian vegetation thickets of any type on site. Botta pocket gopher (Thomomys bottae) and California vole (Microtus californicus) burrows are scattered throughout the more upland areas.
1878
4 3.0 METHODS
The methods employed to produce this report include evaluating the suitability of habitat for CRLF on site by conducting a reconnaissance-level site visit during the day by me on 10 February 2021. I followed the U.S. Fish and Wildlife Service protocol for the CRLF habitat assessment (USFWS 2005) and made observations regarding any amphibians and reptiles observed, or potentially inhabiting the vicinity. Additionally, CRLF occurrence records within

3.1 miles of the Project site (CNDDB 2021) were mapped. Finally, I examined 7.5’ USGS quadrangles and aerial photographs for potentially suitable aquatic habitats within a 3.1-mile radius of the site and connectivity of these habitats with the Project site.

4.0 RESULTS AND DISCUSSION
No CRLF were observed during my day visit of the Project site on February 10, 2021 (see Appendix). I also did not observe any other amphibian species other than some Pacific treefrog (Hyla regilla) egg masses.

Suitable breeding and rearing habitat for CRLF is generally characterized by dense, shrubby riparian vegetation associated with deep (>2.3 feet), still or slow-moving water (see Jennings and Hayes 1994, Jennings 1988, Hayes and Jennings 1988). All of the inundated wetlands that I observed on site were too shallow and ephemeral to support a breeding population of CRLF.

These findings are consistent with previous findings recorded by Monk and Associates (2018) for a small portion of the proposed road alignments on through the eastern part of the Project site.

A review of the most recent California Natural Diversity Database files (CNDDB 2021) revealed that there are no records of CRLF in American Canyon west of Highway 29 almost certainly due to the high amount of vehicle traffic, highway berms, and stream courses being diverted into buried culverts below the freeway. Based on the data from the CNDDB, 3 CRLF occurrences are located within a 3.1-mile radius of the southeast corner of the Study Area, all located east of Highway 29 (Figure 3). The closest sighting is a single adult observed 0.6 miles to the east in the North Slough drainage on July 26, 2006, 2008 (Record #1062). The next closest is another single adult observed 1.1 miles to the southeast in a marsh area near an old quarry pond on August 04, 2008 (Record #896). The third closest is 2.4 miles to the southeast near the Flosden Road where multiple larvae, juveniles, and adults have been observed between 2008 and 2015 (Record #228). There are other records further away within Critical Habitat units SOL-2 and SOL-3 to east and southeast. However, there are no hydrologic connections with any streams that drain the agricultural fields and adjacent foothills east of Highway 29 (a finding also noted by Monk and Associates (2018, 2019). Additionally, the Project site is now nearly entirely surrounded by extensive urban development and infrastructure. Thus, there is no chance for any CRLF to access the site from occupied habitats to the east and southeast due to the presence of Highway 29 (as described above), as well as railroads, urban streets, fences, and buildings. 1879
5 Figure 3. Locations of CRLF within 3.1 miles of the southeast corner of the Project site.

5.0 CONCLUSIONS
Although occupied CRLF habitat is present within 0.6-2.4 miles east and southeast of the Project site, all of these records lie east of Highway 29 which is a major barrier to any potential movements of CRLF to the west due to continuous traffic, highway berms, and the re-routing of Project Site
1880
6 drainages into culverts under the freeway. Additionally, the Project is completely isolated from all areas to the east by Highway 29, railroads, buildings, and other urban infrastructure, and there are no hydrologic connections with any stream channels off-site to the east of Highway 29..

Finally, there is no suitable breeding or rearing habitat for CRLF on site due to the shallow and ephemeral nature of the seasonal wetlands and the lack of any suitable riparian vegetation for cover. Thus, it is my professional opinion that the Project site lacks habitat for this species and that CRLF cannot access the site from surrounding occupied habitats to the east and southeast.

6.0 REFERENCES
California Natural Diversity Database (CNDDB). 2021. Database printout for the Cordelia and Cuttings Wharf 7.5’ USGS quadrangle.

Hayes, M. P., and M. R. Jennings. 1988. Habitat correlates of distribution of the California redlegged frog (Rana aurora draytonii) and the foothill yellow-legged frog (Rana boylii):
implications for management. Pages 144-158 In: R. C. Szaro, K. E. Severson, and D. R.

Patton (technical coordinators). Management of Amphibians, Reptiles and Small Mammals in North America. Proceedings of the Symposium, July 19-21, 1988, Flagstaff, Arizona. U.

S. Forest Service, Rocky Mountain Forest and Range Experiment Station, Fort Collins, Colorado. General Technical Report (RM-166):1-458.

Jennings, M. R. 1988. Natural history and decline of native ranids in California. Pages 61-72 In: H. F. DeLisle, P. R. Brown, B. Kaufman and B. M. McGurty (editors). Proceedings of the conference on California herpetology. Southwestern Herpetologists Society, Special Publication (4):1-143.

Jennings, M. R., and M. P. Hayes. 1994. Amphibian and reptile species of special concern in California. California Department of Fish and Game, Inland Fisheries Division, Rancho Cordova, California. iii+255 p.

Monk and Associates. 2018. Appendix C. Biological resource analysis for the City of American Canyon, Devlin Road and Napa Valley Vine Trail Extension Project, Initial Study/Proposed Negative Declaration. 42 p.+4 appendices.

Monk and Associates. 2019. Biological resource analysis for the City of American Canyon, Green Island Road Reconstruction and Widening Project, Proposed Mitigated Negative Declaration.

Stebbins, R. C. 2003. A field guide to western reptiles and amphibians. Third edition.

Houghton Mifflin Company, Boston, Massachusetts. xiii+533 p.

USFWS (U.S. Fish and Wildlife Service). 2005. Revised guidance on site assessments and field surveys for the California red-legged frog [dated August, 2005]. 26 p. (typewritten). 1881
7 USFWS (U.S. Fish and Wildlife Service). 2010. Endangered and threatened wildlife and plants; revised designation of critical habitat for the California red-legged frog. Federal Register, 75(51):12816-12959. [Wednesday, March 17, 2010].
1882
8 7.0 APPENDIX
Data Sheet from Appendix D of the Revised guidance on site assessment and field surveys for the California red-legged frog (USFWS 2005) completed on 10 February 2021. 1883
9 1884
10 1885
City of American Canyon—Giovannoni Logistics Center Project Draft EIR
FirstCarbon Solutions
C.9 - Brent Helm 2021 Rare Plant Survey Report
C-619
1886

THIS PAGE INTENTIONALLY LEFT BLANK
1887

PROTOCOL-LEVEL

SPECIAL-STATUS NATIVE PLANT SURVEYS
AT THE

GIOVANNONI LOGISTICS CENTER PROJECT,

NAPA COUNTY, CALIFORNIA
Prepared for: Prepared by:

HUFFMAN-BROADWAY GROUP, INC.
828 Mission Avenue
San Rafael, CA 94960
Contact: Robert Perrera
(415) 385-4106

HELM BIOLOGICAL CONSULTING
4600 Karchner Road
Sheridan, CA 95681
Contact: Dr. Brent Helm
(530) 633-0220
August 2021
1888
Rare Plant Surveys Ph: (530) 633-0220
Giovannoni Logistics Center Project Fax: (530) 633-0230 4 PROTOCOL-LEVEL

SPECIAL-STATUS NATIVE PLANT SURVEYS
AT THE

GIOVANNONI LOGISTICS CENTER PROJECT,

NAPA COUNTY, CALIFORNIA

INTRODUCTION
Helm Biological Consulting (HBC), a division Tansley Team, Inc., was contracted by HuffmanBroadway Group (HBG), Inc. to conduct botanical surveys for the presence of special-status plant species with the potential to occur at the Giovannoni Logistics Project (hereafter “Project”), Napa County, California.

PROJECT LOCATION
The Project consists of roughly 208 acres and is situated west of the Calistoga Branch of the Southern Pacific Railroad; north of Green Island Road and the Santa Rosa Branch of the Southern Pacific Railroad; and South of Devin Road, Middleton, Napa County, California (Figure 1).

DEFINITIONS
Several terms relating to biological resources used in the report are described briefly below.

COMMUNITY
A community is an assemblage of populations of plants, animals, bacteria, and fungi that live in an environment and interact with one another, forming a distinctive living system with its own composition, structure, environmental relationships, development, and functions (Whittaker 1975).

SENSITIVE NATURAL COMMUNITY
Sensitive natural communities are communities that are of limited distribution statewide or within a county or region and are often vulnerable to environmental effects of projects. These communities may or may not contain special-status plants or their habitat. A sensitive community has particularly high ecological value or functions. 1889
Esri Community Maps Contributors, County of Napa, County of Solano, Esri, HERE, Garmin, SafeGraph, INCREMENT P, METI/NASA, USGS, Bureau of Land Management, EPA, NPS, US Census Bureau, USDA
County Boundary
Regional Location
37 Petaluma
San Rafael
Napa
Vacaville
Fairfield
Concord
Vallejo
Sonoma
Marin
Solano
Napa
Contra Costa
Figure 1. Location of Giovannoni Logistics Center Project ¯
0 3 5
Miles
Contra Costa
?
Project
Site
0 0.1 0.2
Miles
Prepared by:

Date: 7/29/2021
Data sources:
- ESRI World Topographic Map 2021
Railroad
Railroad
Green Island Rd
Project Site (~208 acres)
80 680
780
1890
Rare Plant Surveys Ph: (530) 633-0220
Giovannoni Logistics Center Project Fax: (530) 633-0230 6 Sensitive communities are considered important because their degradation or destruction could threaten populations of dependent plant and wildlife species and significantly reduce the regional distribution and viability of the community. As the number and extent of sensitive natural community continue to diminish, the endangerment status of dependent special-status (i.e., rare, threatened, or endangered) species could become more precarious, and populations of currently stable species (i.e., non special-status species) could become rare. Loss of sensitive natural communities can also eliminate or reduce important ecosystem functions, such as water filtration by wetlands and bank stabilization by riparian forests or wetlands.

Loss or disturbance of these sensitive communities may constitute significant adverse impact as defined under the California Environmental Quality Act (CEQA). This definition applies to certain natural communities because of their relative scarcity and ecological values, and the vulnerability of remaining occurrences to elimination.

HABITAT
Habitat is the place or type of site where a plant or animal naturally or normally lives and grows.

SPECIAL-STATUS PLANT SPECIES
For the purposes of this document, special status plants include all those that meet one or more of the following criteria:
• Listed or proposed for listing as threatened or endangered under the federal endangered Species Act (ESA) or candidates for possible future listing as threatened or endangered under the ESA (50 C.F.R., § 17.12).
• Listed or candidates for listing by the State of California as threatened or endangered under California Endangered Species Act (CESA) (Fish & G. Code, § 2050 et seq.). In CESA, “endangered species” means a native species or subspecies of plant which is in serious danger of becoming extinct throughout all, or a significant portion, of its range due to one or more causes, including loss of habitat, change in habitat, overexploitation, predation, competition, or disease (Fish & G. Code, § 2062). “Threatened species” means a native species or subspecies of plant that, although not presently threatened with extinction, is likely to become an endangered species in the foreseeable future in the absence of the special protection and management efforts required by CESA (Fish & G.

Code, § 2067). “Candidate species” means a native species or subspecies of plant that the California Fish and Game Commission has formally noticed as being under review by California Department of Fish and Wildlife (CDFW) for addition to either the list of endangered species or the list of threatened species, or a species for which the California Fish and Game Commission has published a notice of proposed regulation to add the species to either list (Fish & G. Code, § 2068).
1891
Rare Plant Surveys Ph: (530) 633-0220
Giovannoni Logistics Center Project Fax: (530) 633-0230 7 • Listed as rare under the California Native Plant Protection Act (Fish & G. Code, § 1900 et seq.). A plant is rare when, although not presently threatened with extinction, the species, subspecies, or variety is found in such small numbers throughout its range that it may be endangered if its environment worsens (Fish & G. Code, § 1901). • Meet the definition of endangered, rare, or threatened species under CEQA Guidelines section 15380, subdivisions (b) and (d), which may include:
 Plants tracked by the California Natural Diversity Database (CNDDB) as California Rare Plant Rank (CRPR) 1 or 2; and
 Plants that may warrant consideration on the basis of declining trends, recent taxonomic information, or other factors. This includes plants tracked by the CNDDB as CRPR 3 or 4.
• Considered locally significant plants, that is, plants that are not rare from a statewide perspective but are rare or uncommon in a local context such as within a county or region (CEQA Guidelines, § 15125, subd. [c]), or as designated in local or regional plans, policies, or ordinances (CEQA Guidelines, Appendix G). Examples include plants that are at the outer limits of their known geographic range or plants occurring on an atypical soil type.

The remainder of this report discusses the methods and results of the 2021 special-status native plant surveys at the Project.
1892
Rare Plant Surveys Ph: (530) 633-0220
Giovannoni Logistics Center Project Fax: (530) 633-0230 8 METHODS
In an effort to determine if the Project supports special-status plants, and in support of CEQA and agency requirements, HBC conducted botanical surveys during the spring of 2021. These surveys utilized CDFW’s protocols identified in “Protocols for Surveying and Evaluating Impacts to Special Status Native Plant Populations and Sensitive Natural Communities” dated March 20, 2018. The method included a pre-field survey and a field survey, both described below.

PRE-FIELD SURVEY
Prior to conducting field surveys, a computer search of the CNDDB and the California Native Plant Society (CNPS) On-line Inventory of Rare and Endangered Plants was conducted to determine whether any special-status plants had been reported onsite or within a 10-mile radius of the Project (CDFW 2021 and CNPS 2021). This search was also used to compile a list of special-status plants that would be targeted during field surveys.

In addition, the following resources were compiled and reviewed:
• US Geological Survey topographic maps (USGS 2021)
• Existing project documents provided by HBG (i.e., Biological Resource Analysis [Monk & Associates, Inc. 2018])
• US Department of Agriculture (USDA), Natural Resources Conservation Service (NRCS) Web Soil Survey (USDA NRCS 2021)
• Project descriptions and initial project designs provided by HBG and/or Buzz Oats

FIELD SURVEY
Special-status plant species identified during the pre-survey investigation as having the potential to occur on the study site were targeted during field surveys. Field surveys for special-status plants incorporated floristic survey methods, as recommended by CDFW (2018). Floristic survey methods require identification of all plant species located onsite. Each species encountered was identified to the extent necessary to determine if it had any legally protected status. Floristic surveys were conducted to ensure that special-status plant species were not inadvertently overlooked because they were not targeted for surveys. Botanical field surveys were conducted by Dr. Brent Helm on April 7, 2021, May 4, 2021, and May 17, 2021. Dr. Helm walked meandering transects throughout the Project to ensure all habitats were adequately 1893
Rare Plant Surveys Ph: (530) 633-0220
Giovannoni Logistics Center Project Fax: (530) 633-0230 9 sampled. Plants were identified using keys in The Jepson Manual (Baldwin et al 2012) and recorded in field notes.

In addition, any milkweed species (Asclepias ssp.) encountered were mapped and their populations counted/estimated. Milkweed is critical for the survival of the monarch butterfly (Danaus plexippus). Caterpillars of this iconic butterfly species feed exclusively on the leaves of milkweeds. On December 15, 2020, the U.S. Fish and Wildlife Service (USFWS) announced the proposed listing of the monarch as “Warranted, but Precluded”. This means that, while the USFWS has determined the Monarch meets the definition of a threatened or endangered species, there are currently not enough resources (e.g., funding, personnel) to list the species presently, although listing could occur in the future. The monarch is also considered a “Conservation Priority” under CESA.

Several reference sites with known special-status plants targeted for field surveys were visited to:

1. Determine whether those special-status plants were identifiable at the times of year the botanical field surveys took place; and

2. To obtain a visual image of the special-status plants, associated habitat, and associated natural communities.

Reference sites included:
 Little Egbert Tract for Suisun Marsh aster, Mason's lilaeopsis and Delta tule pea.  Sacramento Utilities Municipal District’s Rancho Seco Conservation Bank lands for legenere and dwarf downingia.
 Gentry Logistics Project, Suisun for Contra Costa goldfields. 1894
Rare Plant Surveys Ph: (530) 633-0220
Giovannoni Logistics Center Project Fax: (530) 633-0230 10 RESULTS

ENVIRONMENTAL CONDITIONS

HISTORIC CONDITIONS
Historically, the Project lied roughly midway between the foothills of the Sulfur Springs Mountains and the tidal marshes of the Napa River and was part of the watershed for an unnamed tributary (dubbed “South Fork” for the purposes of this discussion) of Fagan Slough.

The multiple tributaries, of which Fagan Slough was one, was appropriately named - Brazos (“Arms” in Spanish) given to the cluster of tidal channels in this region. However, given the Site’s, elevation it was probably just above the tidal influence of the Napa River. Prior to the turn of the century, the South Fork of the Fagan Slough onsite was orientated in a west-east direction.

The headwaters of this drainage originated in the foothills to the east of the Project. However, by the early 1900’s, most of the upper portion of the South Fork had been diverted and channelized.

During a similar time period, a substantial ditch (orientated in a north-south direction) was excavated in an attempt to drain a large wetland (situated along the northern edge of the Santa Rosa Branch of the Southern Pacific Railroad) into the South Fork onsite. Unfortunately with the offsite portions of the South Fork diverted or removed, the upper portion of the North Fork onsite received reduced flows. Further hydrologic inputs to this drainage were reduced from the construction of several ditches, most orientated in an east-west fashion along the northern boundary of the Project. The overall effect of these ditches has reduced the resident time of surface water onsite.

Additionally, the disking that has occurred onsite tended to “smear” the wetlands across the landscape which increased the ponding surface area while decreasing the ponding depth and duration. Disking also decreases soil compaction; therefore, increasing the soils ability to absorb water, thus delaying the onset of ponding and decreasing ponding duration within the wetlands.

In conclusion, most of the disturbances to the site occurred long before historical aerial photographs and topographic maps could have document the changes. The railroads, numerous roads, channels, and ditches had occurred prior to or just after the turn of the century.

CURRENT CONDITIONS

CLIMATE
The climate at the Project is typical of the northern portion of the Bay Area, with an average low temperature in January of 38.5 degrees Fahrenheit (o
F) and average high temperature in July of

83.3 o
F. Rainfall averages 24.2 inches per year, most of which falls during the winter months. On average, there are 265 sunny days per year at the Project (Bestplaces 2021). 1895
Rare Plant Surveys Ph: (530) 633-0220
Giovannoni Logistics Center Project Fax: (530) 633-0230 11 TOPOGRAPHY AND HYDROLOGY
The Project consist of a relatively flat piece of ground sloping from east to west with the highest elevation at roughly 60 feet (ft) above mean sea level (msl) located in the southeast corner and lowest elevation in the northwest corner of roughly 25 ft msl.

The Project occurs within the Tulucay Creek-Frontal San Pablo Bay Estuaries watershed, Environmental Protection Agency (EPA) Hydrologic Unit Code (HUC10) 1805000204 (Figure 2). Additionally, most of the Project occurs within the Tulucay Creek-Frontal San Pablo Bay Estuaries subwatershed (HUC12: 180500020402), while a small portion of the Project along the southern boundary occurs in the American Canyon Creek-Frontal San Pablo Bay Estuaries (HUC12: 180500020401) (Figure 2). The Napa River occurs roughly 1.8 miles to the west and roughly 1.3 miles to the southwest of the Project.

Direct inception of rainfall occurs within the numerous depressional areas consisting of seasonally inundated wetlands (vernal pools and seasonal wetlands). However, ditches have been historically excavated in an attempt to drain many of the larger onsite wetlands (See Historic Conditions section below for more details). Most of the ditches are orientated to drain to the north where they intercept remnant segments, or channelized portions thereof, of the South Fork of Fagan Slough/Creek. Additional hydrologic surface inputs to the remaining channels of Fagan Slough are derived from upslope but offsite watersheds that have been diverted into ditches which convey storm water and irrigation runoff to the northeast corner of the site via a culvert situated under the Calistoga Branch of the Southern Pacific Railroad. Other hydrological inputs may be derived from irrigation and storm water runoff occurring within the large industrial areas located to the south of the Site.

SOILS
According to the Web Soil Survey (USDA NRCS 2021), three soil map units are present onsite (Table 1 and Figure 3).
1896
The County of Napa, Earthstar Geographics
Figure 2. Watershed
Project Site (~208 acres)
Watershed
American Canyon Creek-Frontal San Pablo Bay
Estuaries (HUC12: 180500020401)
Tulucay Creek-Frontal San Pablo Bay Estuaries
(HUC12: 180500020402)
Tulucay Creek-Frontal San Pablo Bay Estuaries
(HUC10: 1805000204)
0 2 4
Miles ¯
Prepared by:

Date: 7/29/2021
Data sources:
- ESRI World Imagery Map 2021
- USDA-NRCS, USGS, EPA Watershed
Boundary and National Hydrology
Dataset 2021
1897
The County of Napa, Maxar
Regional Location
37 Petaluma
San Rafael
Napa
Vacaville
Fairfield
Concord
Vallejo
Sonoma
Marin
Solano
Napa
Contra Costa
Figure 3. Soils
¯
0 3 5
Miles
Contra Costa
?
Project
Site Prepared by:

Date: 7/29/2021
Data sources:
- ESRI World Imagery Map 2021
- NRCS Web Soil Survey 2021
80 680
780
0 0.1 0.2
Miles
Project Site (~208 acres)
Soils
Clear Lake clay, drained, 0
to 2 percent slopes, MLRA
14 Haire clay loam, 2 to 9
percent slopes
Haire loam, 2 to 9 percent
slopes
County Boundary
1898
Rare Plant Surveys Ph: (530) 633-0220
Giovannoni Logistics Center Project Fax: (530) 633-0230 14 Table 1. Hydric Soil Conditions, Percent of Components and Geographic Position of Soil Series an Associated Inclusions Mapped by NRCS at the Giovannoni Logistics Center Project, Napa County, California Soil Series Inclusions
Name
Hydric
Soil Percent
Geomorphic
Position Name
Hydric
soil Percent
Geomorphic
Position
116 - Clear Lake
clay, drained, 0
to 2 percent
slopes, MLRA
14 Yes 90 Basin floors
Unnamed ? 5 Alluvial flats
Cambell No 3
Foodplains, Toe
of alluvial fans,
Basin margins
Sunnyvale No 2 Level flood
plains and basins
146 - Haire
loam, 2 to 9
percent slopes
No 85
Terraces,
Alluvial fans,
Footslopes
Clear Lake Yes 5 Alluvial fans
148 - Haire clay
loam, 2 to 9
percent slopes
No 85
Terraces,
Alluvial fans,
Footslopes
Clear Lake Yes 5 Alluvial fans

VEGETATION COMMUNITIES
The combination of the Project’s climate, hydrology, soils and disturbance regime (draining and disking) supports community types typical of the North Bay Area. The majority of the site consists of annual grasslands, with scattered seasonally inundated wetland depressions consisting of vernal pools, seasonal pools, swales, ephemeral drainages, and ditches (See Exhibit A for Confirmed Aquatic Resources Delineation Map).

A description of each of the six community/habitat types including dominant vegetation is provided below.

Annual Grassland. Due to the current ungrazed condition of the Site, the annual grassland habitat consists of mostly thatchy nonnative annual grass species including: medusa-head grass (Elymus caput-medusae), soft chess (Bromus hordeaceus), wild oat (Avena barbata), ripgut brome (Bromus diandrus), and hare barely (Hordeum murinum ssp. leporinum).

Subdominant grasses include Mediterranean barley (Hordeum marinum ssp. gussoneanum), Italian ryegrass (Festuca perennis), and annual bluegrass (Poa annua), especially when this habitat transitions to the wetlands onsite. Forbes are present, but generally are more abundant along the sites edges or where the grassland shifts to wetland. These forbs include field mustard (Brassica rapa), broadleaf filaree (Erodium bothrys), wild lettuce (Lactuca serriola), wild mustards (Raphanus sativa and R. raphanistrum)), and yellow star thistle (Centaurea solstitialis).
1899
Rare Plant Surveys Ph: (530) 633-0220
Giovannoni Logistics Center Project Fax: (530) 633-0230 15 Vernal Pool. Vernal pools are seasonally flooded landscape depressions where water ponds because of limitations to surface or subsurface drainage. Surface drainage is prevented by a depressed or concave topography. Soil layers impervious to the downward infiltration of water inhibit subsurface drainage resulting in swallow ponding during the wet-season. Vernal pools support distinct vegetation adapted to periodic or continuous inundation during the wet season, and the absence of either ponded water or wet soil during the dry season.

Vernal pools are considered sensitive natural communities by USFWS and CDFW and their occurrences are tracked by CNDDB.

Vernal pools are lentic habitats which pond water rather than conveying it (lotic) such as swales, ditches, and ephemeral drainages. The adjective “vernal” refers to its occurrence in the spring”.

However, the term “vernal” is used in this report to denote the presence of two or more vernal habitat indicator plants (Downingia ssp., Lasthenia ssp., Eryngium ssp., Plagiobothrys ssp., Psilocarpus ssp., etc.). In contrast, the term “seasonal” refers to those wetlands that are seasonally inundated but do not support the presence of two or more vernal habitat indicator plants.

Vernal pools occurring onsite support plant species typical of a combination of the Santa Rosa Region and the Solano-Colusa Region (Keeler-Wolf et al. 1998). Vernal pool basins are dominated by small stipitate popcorn flower (Plagiobotrys stipitatus var. micranthus) and annual semaphoregrass (Pleuropogon californicus). Other subdominant species included: water pygmyweed (Crassula aquatica), common spike rush (Eleocharis macrostachya), smooth goldfields (Lasthenia glaberrima), Jepson’s button celery (Eryngium aristulatum var. aristulatum), and hyssop loosestrife (Lythrum hyssopifolia).

Other plant species which occur to a lesser extent onsite include: water-starwort (Callitriche marginata), Italian ryegrass (Festuca perennis), Mediterranean barley (Hordeum marinum subsp. gussoneanum), toad rush (Juncus bufonius), and annual blue grass (Poa annua).

Seasonal Pool. Seasonal pools are shallow to deep topographic depressions underlain by soils with slow water permeability that promote ponding or soil saturation during the wet season. It is presumed that most of the seasonal pools onsite were historically vernal pools that have had their hydroregimes altered (either increased or decreased) due to human activities (e.g., disking, draining, ground water pumping, irrigation runoff, etc.).

The vegetation within seasonal pools is similar to vernal pools described above, except they lack the presence of two or more vernal habitat plant indicators. Seasonal wetlands support a number of plant species adapted to periodic inundation during the growing season. Typical seasonal wetland plant species include Italian ryegrass (Festuca perennis), rabbit's foot grass (Polypogon monspeliensis), ditch beard grass (Polypogon interruptus), Bermuda grass (Cynodon dactylon), curly dock (Rumex cripus), Baltic rush (Juncus balticus ssp. ater), Mediterranean barley 1900
Rare Plant Surveys Ph: (530) 633-0220
Giovannoni Logistics Center Project Fax: (530) 633-0230 16 (Hordeum marinum ssp. gussoneanum), toad rush (Juncus bufonius var. bufonius), and umbrella sedge (Cyperus eragrostis).

Swale. Swales are broad, shallow (< 1 ft deep), seasonally inundated areas that primarily convey water during and shortly after rain events. Surface runoff collects in swales, wetting and saturating the soil for short periods. Swales are typically vegetated and have poorly defined channels that lack a distinct bed and bank characterizing the ephemeral drainage habitats described below.

Swale vegetation is a transitional community that is wetter than the surrounding annual grassland but drier than the ephemeral drainages. Similar to pool habitats, there are two types of swales onsite depending on the presence or absence of vernal habitat plant indicators. Vernal swales have plant compositions similar to vernal pools. Whereas season swales have plant species compositions more similar to seasonal pools. The major difference between swales and pools is the hydrologic regime. Swales generally convey water whereas pools pond it.

Ephemeral Drainage. The ephemeral drainage habitat onsite are characterized by broad (> 5 feet in width) and deep (1-3 feet in depth) channels with well-defined beds and banks. Their bottoms are smoothly concave in cross-section (no sharp edges), with a fairly sharp and steep bank near the existing grade. This habitat receives hydrologic inputs from swale and ditch habitats as well as overland flow.

Large portions of this habitat have been lost or converted to ditch and swale habitat from ditching and disking, respectively. The ephemeral drainage habitat is most defined at the northwest corner of the site where the historic meanders of the South Fork of Fagan Slough (see Historic Condition section above).

The ephemeral drainages onsite are dominated by plants species associate with emergent marsh habitat which are characterized by a predominance of perennial monocots (a subclass of herbaceous seed plants with a single stem/leaf structure) that grow in permanently or semipermanently flooded (or saturated) soils that emerge from the water. The plants associated with this habitat include Baltic rush (Juncus balticus ssp. ater), Mexican rush (J. mexicanus), common spike rush (Eleocharis macrostachya), and umbrella sedge (Cyperus eragrostis). Some of the deeper areas are dominated entirely by Bermuda grass (Cynodon dactylon) with patches of broadleaf cattail (Typha latifolia),
Ditch. Ditch habitats onsite are human excavated channels for the purposes of surface water conveyance offsite. These habitats are general “V” or “U” shaped in cross-section and are 1-3 feet wide and general 1-2 feet in depth. The smaller ditches generally occur in the southern portion of the Project and are oriented in a north-south direction, thus draining the larger wetlands and terminating into the west-east orientated larger ditches, ephemeral drainages, or 1901
Rare Plant Surveys Ph: (530) 633-0220
Giovannoni Logistics Center Project Fax: (530) 633-0230 17 swales located in the northern portion of the Project. The larger ditches flow surface water from the east to the west.

Vegetation within the ditch habitat is dependent on the hydrologic regime. The larger deeper ditches have similar vegetation composition to the ephemeral drainage habitat onsite. Similarly, the small and medium size ditches have vegetation similar to the annual grassland and swale habitats, respectively.

SPECIAL-STATUS PLANTS
The search of the CNNDB and CNPS On-line Inventory of Rare and Endangered Plants did not reveal any special-plant species occurring onsite (CNPS 2021). However, 37 special-status plants are known to occur within a 10-mile radius of the Project (Figure 4). However, of these 37 plants only 23 were associated with habitats that are known to occur onsite (Appendix A). The remaining 14 plants were not considered to have potential to occur onsite since they inhabit plant communities (i.e., chaparral, cismontane woodland, coastal brackish or saltwater marsh and swamps, coastal scrub, coast bluff shrub, and lower montane coniferous forest) that are not present onsite.

No special-status plant species were observed onsite. In general, most of the plants listed in Appendix A are not likely to occur onsite. Only a few have low potential for future occurrence.

A list of all vascular plant species observed onsite during field surveys is included in Appendix B. Representative photographs of habitat onsite are included in Appendix C. 1902
24 19
14 17
7 35
16 33
6 16
19 23
15 35
21 15
37 33
18 7
2 25
36 36
26 36
34 32
26 29
33 26
30 26
26 33
29 15
15 13
28 26
17 15
20 15
34 26 35
26 12
27 33
18 12
36 34
26 26
26 5
10 17
26 26
25 8
26 36
26 12
34 25
12 12
12 12
20 20
20 33
18 12
36 14
12 29
30 12
37 29
33 12
29 18
18 33
26 14
26 11
37 9
28 14
12 7
26 26
26 33
14 31
30 17
4 4
22 17
17 17
7 26
17 29
29 5
12 30 33
1 3
5 14
Esri, HERE, Garmin, SafeGraph, METI/NASA, USGS, Bureau of Land Management, EPA, NPS, USDA
Figure 4. Known Special-Status Plant Species Locations within the Vicinity of the Giovannoni Logistics Center Project
Project Site (~208 acres)
Plant Species

1. Bolander's water-hemlock (Cicuta maculata var. bolanderi)

2. Brewer's western flax (Hesperolinon breweri)

3. California beaked-rush (Rhynchospora californica)

4. Carquinez goldenbush (Isocoma arguta)

5. Congdon's tarplant (Centromadia parryi ssp. congdonii)

6. Contra Costa goldfields (Lasthenia conjugens)

7. Delta tule pea (Lathyrus jepsonii var. jepsonii)

8. Diablo helianthella (Helianthella castanea)

9. Franciscan onion (Allium peninsulare var. fanciscanum)

10. Greene's narrow-leaved daisy (Erigeron grennei)

11. Henderson's bent grass (Agrostis hendersonii)

12. Jepson's coyote-thistle (Eryngium jepsonii)

13. Jepson's leptosiphon (Leptosiphon jepsonii)

14. Lyngbye's sedge (Carex lyngbyei)

15. Marin knotweed (Polugonum marinense)

16. Mason's lilaeopsis (Lilaeopsis masonii)

17. Napa bluecurls (Trichostema ruygtii)

18. Napa false indigo (Amorpha californica var. napensis)

19. Rincon Ridge ceanothus (Ceanothus confusus)

20. San Joaquin spearscale (Extriplex joaquinana)

21. Serpentine Bunchgrass (Calamagrostis ophitidis)

22. Suisun Marsh aster (Symphyotrichum lentum)

23. Tiburon paintbrush (Castilleja affinis var. neglecta)

24. alkali milk-vetch (Astragalus tener var. tener)

25. big tarplant (Blepharizonia plumosa)

26. big-scale balsamroot (Balsamorphiza macrolepis)

27. chaparral ragwort (Senico aphanactis)

28. dwarf downingia (Downingia pusilla)

29. fragrant fritillary (Fritillaria liliacea)

30. holly-leaved ceanothus (Ceanothus purpureus)

31. legenere (Legenere limosa)

32. narrow-anthered brodiaea (Brodiaea leptandra)

33. oval-leaved viburnum (Viburnum ellipticum)

34. pappose tarplant (Centromadia parryi ssp. parryi)

35. saline clover (Trifolium hydrophilum)

36. soft salty bird's-beak (Chloropyron molle ssp. molle)

37. two-fork clover (Trifolium amoenum)
Date: 7/28/2021
Prepared by:
0 2 4
Miles ¯
Data sources:
- CDFW CNDDB
2021
- ESRI World
Topographic Map
2021
1903
Rare Plant Surveys Ph: (530) 633-0220
Giovannoni Logistics Center Project Fax: (530) 633-0230 19 DISCUSSION
Although the low rainfall of 2020/2021 within the vicinity of the Project (UCIPM 2021) may have influenced the potential presence of special-status plant species onsite, our results are similar to those of Monk & Associates, Inc. (2018) who conducted special-status plant surveys during March through July 2016. Because two years of special-status plant surveys with negative results have been conducted onsite within a five-year period, impacts to special status-plants would not be expected from Project implementation.
1904
Rare Plant Surveys Ph: (530) 633-0220
Giovannoni Logistics Center Project Fax: (530) 633-0230 20 LITERATURE CITED
Baldwin, B. G, D. H. Goldman, D. J. Keil, R, Patterson, T. J. Rosatti, and D. H. Wilken. ed. 2012. The Jepson Manual, Vascular Plants of California. University of California Press, Berkeley, California.

BestPlaces. 2021. Climate in American Canyon, California. https://www.bestplaces.net/climate/city/california/american_canyon California Department of Fish and Wildlife (CDFW). 2018. Protocols for Surveying and Evaluating Impacts to Special Status Native Plant Populations and Sensitive Natural Communities. 12pp.
_____. California Natural Diversity Data Base (CNDDB). 2021. RareFind 5. https://wildlife.ca.gov/Data/CNDDB/Maps-and-Data. Website accessed April 2021.

California Native Plant Society (CNPS). 2021. Inventory of rare and endangered vascular plants of California. https://rareplants.cnps.org/. Website accessed April 2021.

Keeler-Wolf, T., D. R. Elam, K. Lewis, and S. A. Flint. 1998. California vernal pool assessment preliminary report. California Department of Fish and Game, Sacramento, California. 159 pages.

Monk & Associates, Inc. 2018. Biological Resources Analysis Devlin Road/Vine Trail Extension Project, City of American Canyon, California. 69 pp. Dated: October 15, 2018.

U.S. Geological Survey (USGS). 2021. Get Maps TopoView – National Geologic Map Database. https://ngmdb.usgs.gov/topoview/viewer/#4/40.00/-100.00 U.S. Department of Agriculture (USDA) National Resources Conservation Service (NRCS). 2021. Web Soil Survey. http://websoilsurvey.nrcs.usda.gov/app/. Website accessed July 2021.

University of California Integrated Pest Management System (UCIPM). 2021. Weather, models & degree-days. Weather data from Napa (Carneros) weather monitoring station. http://ipm.ucanr.edu/WEATHER/SITES/napa.html
Whittaker, R. H. 1975. Communities and Ecosystems. 2nd ed. New York: Macmillan. 1905
Rare Plant Surveys Ph: (530) 633-0220
Giovannoni Logistics Center Project Fax: (530) 633-0230 EXHIBIT A.

AQUATIC RESOURCE DELINEATION MAP
1906
1907
Rare Plant Surveys Ph: (530) 633-0220
Giovannoni Logistics Center Project Fax: (530) 633-0230 APPENDIX A.

SPECIAL-STATUS PLANT SPECIES ORIGINALLY TARGETED

FOR SURVEYS AT THE

GIOVANNONI LOGISTICS CENTER PROJECT
1908
Fed
List
State
List
Global
Rank
State
Rank
Ca
Rare
Plant
Rank
Agrostis hendersonii Henderson's bent grass Poaceae annual herb Apr-Jun None None G2Q S2 3.2 Valley and foothill grassland, Vernal pools
Not Present. Protocol surveys were negative for this
species. Note: This species is wetland dependent
and its presence could be affected by the below
annual rainfall that occurred in 2020/2021 wetseason.

Allium
peninsulare var. francisc
anum
Franciscan onion Alliaceae
perennial
bulbiferous
herb
(Apr) MayJun
None None G5T2 S2 1B.2
Clay soils (volcanic or
serpentine) in Cismontane
woodland, Valley and foothill
grassland
Not Present. Protocol surveys were negative for this
species. Although clay soils (Clear Lake) occur
onsite, this species is general associated with
volcanic or serpentine derived soils which are not
present onsite.

Astragalus
tener var. tener alkali milk-vetch Fabaceae annual herb Mar-Jun None None G2T1 S1 1B.2 Playas, Valley and foothill grassland, Vernal pools Not Present. Protocol surveys were negative for this
species. No Astragalus species were observed
onsite. This species generally occurs in alkaline soils which are not present onsite.

Balsamorhiza macrolepis big-scale balsamroot Asteraceae perennial herb Mar-Jun None None G2 S2 1B.2
Chaparral, Cismontane
woodland, Valley and foothill
grassland
Not Present. Protocol surveys were negative for this
species. No Balsamorhiza species were observed
onsite. This species is perennial and would have
been present and visible during surveys.

Brodiaea leptandra narrow-anthered
brodiaea Themidaceae
perennial
bulbiferous
herb
May-Jul None None G3? S3? 1B.2
Broad-leafed upland forest,
Chaparral, Cismontane
woodland, Lower montane
coniferous forest, Valley and
foothill grassland
Not Present. Protocol surveys were negative for this
species.

Carex lyngbyei Lyngbye's sedge Cyperaceae
perennial
rhizomatous
herb
Apr-Aug None None G5 S3 2B.2 Marshes and swamps
Not Present. Protocol surveys were negative for this
species. No Carex species were observed onsite.

This species is perennial and would have been
present and visible during surveys.

Castilleja
affinis var. neglecta Tiburon paintbrush Orobanchaceae
perennial
herb
(hemiparasitic
)
Apr-Jun FE ST
G4G5T1
T2
S1S2 1B.2 Valley and foothill grassland
Not Present. Protocol surveys were negative for this
species. This species has a very limited distribution
and is associated with serpentine soils which are
not present onsite.

Centromadia
parryi ssp. congdonii Congdon's tarplant Asteraceae annual herb May-Oct (Nov) None None G3T1T2 S1S2 1B.1 Valley and foothill grassland Not Present. Protocol surveys were negative for this
species. Note: This species is wetland dependent
and its presence could be affected by the below
annual rainfall that occurred in 2020/2021 wetseason.

Centromadia
parryi ssp. parryi pappose tarplant Asteraceae annual herb May-Nov None None G3T2 S2 1B.2 Chaparral, Coastal prairie,
Marshes and swamps,
Meadows and seeps, Valley
and foothill grassland
Not Present. Protocol surveys were negative for this
species. Note: This species is wetland dependent
and its presence could be affected by the below
annual rainfall that occurred in 2020/2021 wetseason.

General Habitat
Appendix A. Special-Status Plant Species Originally Targeted for Surveys at the Giovannoni Logistics Center Project Special-Status Listings and Ranks
Scientific Name Common Name Plant Family Lifeform
Blooming
Period Occurrence at the Project Site
1909
Fed
List
State
List
Global
Rank
State
Rank
Ca
Rare
Plant
Rank General Habitat
Appendix A. Special-Status Plant Species Originally Targeted for Surveys at the Giovannoni Logistics Center Project Special-Status Listings and Ranks
Scientific Name Common Name Plant Family Lifeform
Blooming
Period Occurrence at the Project Site
Downingia pusilla dwarf downingia Campanulaceae annual herb Mar-May None None GU S2 2B.2 Valley and foothill grassland, Vernal pools
Not Present. Protocol surveys were negative for this
species. Note: This species is wetland dependent
and its presence could be affected by the below
annual rainfall that occurred in 2020/2021 wetseason.

Eryngium jepsonii Jepson's coyote-thistle Apiaceae perennial herb Apr-Aug None None G2 S2 1B.2 Valley and foothill grassland, Vernal pools Not Present. Protocol surveys were negative for this
species. Note: This species is wetland dependent
and its presence could be affected by the below
annual rainfall that occurred in 2020/2021 wetseason.

Extriplex joaquinana San Joaquin spearscale Chenopodiaceae annual herb Apr-Oct None None G2 S2 1B.2 Chenopod scrub, Meadows
and seeps, Playas, Valley and
foothill grassland
Not Present. Protocol surveys were negative for this
species. No Extriplex species were observed onsite.

This species generally occurs in alkaline soils which
are not present onsite.

Fritillaria liliacea fragrant fritillary Liliaceae
perennial
bulbiferous
herb
Feb-Apr None None G2 S2 1B.2
Cismontane woodland,
Coastal prairie, Coastal scrub,
Valley and foothill grassland
Not Present. Protocol surveys were negative for this
species.

Isocoma arguta Carquinez goldenbush Asteraceae perennial shrub Aug-Dec None None G1 S1 1B.1 Valley and foothill grassland Not Present. Protocol surveys were negative for this
species. No Isocoma species were observed onsite.

This species is a perennial shrub and would have
been visible during surveys, if present.

Lasthenia conjugens Contra Costa goldfields Asteraceae annual herb Mar-Jun FE None G1 S1 1B.1 Vernal pools within
Cismontane woodland,
Playas, Valley and foothill
grassland
Not Present. Protocol surveys were negative for this
species. Note: This species is wetland dependent
and its presence could be affected by the below
annual rainfall that occurred in 2020/2021 wetseason.

Lathyrus
jepsonii var. jepsonii Delta tule pea Fabaceae perennial herb May-Jul (AugSep) None None G5T2 S2 1B.2 Marshes and swamps Not Present. Protocol surveys were negative for this
species. Note: This species is generally associated
with tidal influenced perremial waterways. This
species was present and highly visible at the chosen
Reference Site. Therefore, this species would have
been observed onsite, if present.

Legenere limosa legenere Campanulaceae annual herb Apr-Jun None None G2 S2 1B.1 Vernal pools Not Present. Protocol surveys were negative for this
species. Note: This species is wetland dependent
and its presence could be affected by the below
annual rainfall that occurred in 2020/2021 wetseason.

Leptosiphon jepsonii Jepson's leptosiphon Polemoniaceae annual herb Mar-May None None G2G3 S2S3 1B.2 Chaparral, Cismontane
woodland, Valley and foothill
grassland
Not Present. Protocol surveys were negative for this
species.
1910
Fed
List
State
List
Global
Rank
State
Rank
Ca
Rare
Plant
Rank General Habitat
Appendix A. Special-Status Plant Species Originally Targeted for Surveys at the Giovannoni Logistics Center Project Special-Status Listings and Ranks
Scientific Name Common Name Plant Family Lifeform
Blooming
Period Occurrence at the Project Site
Lilaeopsis masonii Mason's lilaeopsis Apiaceae
perennial
rhizomatous
herb
Apr-Nov None SR G2 S2 1B.1
Mudflats within marshes and
swamps, Riparian scrub
Not Present. Protocol surveys were negative for this
species. Note: This species is generally associated
with tidal influenced perremial waterways. This
species was present and highly visible at the chosen
Reference Site. Therefore, this species would have
been observed onsite, if present.

Symphyotrichum lentum Suisun Marsh aster Asteraceae
perennial
rhizomatous
herb
(Apr) MayNov
None None G2 S2 1B.2 Marshes and swamps
Not Present. Protocol surveys were negative for this
species. Note: This species is generally associated
with tidal influenced perremial waterways.

Trichostema ruygtii Napa bluecurls Lamiaceae annual herb Jun-Oct None None G1G2 S1S2 1B.2 Chaparral, Cismontane
woodland, Lower montane
coniferous forest, Valley and
foothill grassland, Vernal
pools
Not Present. Protocol surveys were negative for this
species.

Trifolium amoenum two-fork clover Fabaceae annual herb Apr-Jun FE None G1 S1 1B.1 Coastal bluff scrub, Valley and foothill grassland
Not Present. Protocol surveys were negative for this
species. Note: This species is wetland dependent
and its presence could be affected by the below
annual rainfall that occurred in 2020/2021 wetseason.

Trifolium hydrophilum saline clover Fabaceae annual herb Apr-Jun None None G2 S2 1B.2 Marshes and swamps, Valley
and foothill grassland, Vernal
pools
Not Present. Protocol surveys were negative for this
species. Note: This species is wetland dependent
and its presence could be affected by the below
annual rainfall that occurred in 2020/2021 wetseason.

Federal
FE
State
SR
ST
Global Rank
G1
G2
G3
G5
GU
G#G#
G#T#
?
Q
Imperiled — At high risk of extinction due to very restricted range, very few populations (often 20 or fewer), steep declines, or other factors.

Definition
Vulnerable — At moderate risk of extinction or elimination due to a restricted range, relatively few populations (often 80 or fewer), recent and widespread declines, or other factors.

Secure — Common; widespread and abundant.

Unrankable — Currently unrankable due to a lack of information or due to substantially conflicting information about status or trends.

Range Rank — A numeric range rank (e.g., G2G3) is used to indicate the range of uncertainty about the exact status of a taxon or community.

Definition
Listed as rare under California Endangered Species Act (CESA) Listed as threatened under the CESA
Definition
Federally Endangered (listed as Endangered under Federal Endangered Species Act [ESA]) Infraspecific Taxon — The status of infraspecific taxa (subspecies or varieties) are indicated by a "T-rank" following the species' Global Rank. Rules for assigning T-ranks follow the same principles as those for Global Ranks. However, a T-rank cannot imply the subspecies or variety is more abundant than the species. With the subspecies, the G-rank reflects the condition of the entire species, whereas the T-rank reflects the global situation of just the subspecies or variety.

Qualifier: Inexact Numeric Rank — A question mark represents a rank qualifier, denoting an inexact or uncertain numeric rank.

Qualifier: Questionable Taxonomy — The distinctiveness of this entity as a taxon or community at the current level is questionable; resolution of this uncertainty may result in change from a species to a subspecies or hybrid, or inclusion of this taxon or type in another taxon or type, with the resulting taxon having a lower-priority (numerically higher) conservation status rank.

Critically Imperiled — At very high risk of extinction due to extreme rarity (often 5 or fewer populations), very steep declines, or other factors. 1911
Fed
List
State
List
Global
Rank
State
Rank
Ca
Rare
Plant
Rank General Habitat
Appendix A. Special-Status Plant Species Originally Targeted for Surveys at the Giovannoni Logistics Center Project Special-Status Listings and Ranks
Scientific Name Common Name Plant Family Lifeform
Blooming
Period Occurrence at the Project Site
State Rank
S1
S2
S3
S#S#
?
Description
Range Rank — A numeric range rank (e.g., S2S3) is used to indicate any range of uncertainty about the status of the species or community.

Qualifier: Inexact or Uncertain — A question mark represents a rank qualifier, denoting an inexact or uncertain numeric rank.

Critically Imperiled — Critically imperiled in the state because of extreme rarity (often 5 or fewer occurrences) or because of some factor(s) such as very steep declines making it especially vulnerable to extirpation from the state.

Imperiled — Imperiled in the state because of rarity due to very restricted range, very few populations (often 20 or fewer), steep declines, or other factors making it very vulnerable to extirpation from the nation or state.

Vulnerable — Vulnerable in the state due to a restricted range, relatively few populations (often 80 or fewer), recent and widespread declines, or other factors making it vulnerable to extirpation. 1912
Rare Plant Surveys Ph: (530) 633-0220
Giovannoni Logistics Center Project Fax: (530) 633-0230 APPENDIX B.

LIST OF ALL VASCULAR PLANT SPECIES OBSERVED
1913
Scientific Name Common Name
Amaranthus albus* Pigweed amaranth
Anthemis cotula* Mayweed
Avena barbata* Slender oats
Baccharis pilularis Coyote brush
Brassica rapa* Field mustard
Briza minor* Little qauking grass
Bromus diandrus* Ripgut grass
Bromus hordeaceus* Soft brome
Callitriche marginata California water starwort
Carduus pycnocephalus ssp. pycnocephalus Italian thistle Centaurea solstitialis* Yellow star-thistle
Centromadia pungens Common spikeweed
Cerastium glomeratum* Mouse-ear chick-weed
Chichorium intybus* Chicory
Cirsium vulgare* Bull thistle
Claytonia perfoliata ssp. perfoliata Minor's lettuce
Convulvulus arvensis* Field bindweed
Cotula coronopifolia* Brass buttons
Crassula aquatica Water pygmy-weed
Croton setigerus Turkey-mullein
Crypsis schoenoides* Swampgrass, swamp timothy
Cynara cardunculus* Artichoke thistle
Cynodon dactylon* Bermuda grass
Cyperus eragrostis Tall flatsedge
Eleocharis macrostachya Common spike rush
Elymus caput-medusae * Medusa-head grass
Elymus triticoides Beardless wild rye
Epilobium branchycarpum Tall annual willow herb
Epilobium ciliatum Slender willow herb
Erigeron canadensis Canadian horseweed
Erodium botrys* Broadleaf filaree
Erodium cicutarium* Red-stem filaree
Erodium mochatum* White-stem filaree
Eryngium aristulatum var. aristulatum Jepson's button celery Euphorbia oblongata* Eggleaf spurge
Euphorbia oblongata* Egg leaf spurge
Festuca arundinacea* Tall festuca
Festuca bromoides* Six-weeks grass
Festuca perennis* Italian ryegrass
Foeniculum vulgare* Fennel
Fraxinus latifolia Oregon ash
Galium aparine Bedstraw
List of Vascular Plants Observed in the Project
1914
Scientific Name Common Name
List of Vascular Plants Observed in the Project
Geranium dissectum* Cut-leave geranium
Glyceria declinata* Waxy manna grass
Gnaphalium palustre Lowland cudweed
Helminthotheca echioides* Prickly ox-tounge
Hemizonia congesta ssp. luzulifolia White hayfield tarweed Hirschfeldia incana* Short-pod mustard
Hordeum brachyantherum ssp. branchyantherum Meadow barley Hordeum marinum ssp. gussoneanum* Mediterranean barley
Hordeum murinum ssp. leporinum* Hare barley
Juncus balticus ssp. ater Baltic rush
Juncus bufonius var. bufonius Toad rush
Juncus mexicanus Mexican rush
Lactuca serriola* Prickly wild lettuce
Lasthenia glaberrima Smooth goldfields
Leontodon saxitilis ssp. longirostris* Hairy hawkbit
Lepidium latifolium* Perrenial peppergrass
Leymus triticoides Creeping wildrye
Lotus corniculatus* Birds' foot trefoil
Lysimachia arvensis Scarlet pipernel
Lythrum hyssopifolia* Hyssop loosestrife
Malva parviflora* Cheeseweed
Paspalum dilatatum* Dallis grass
Periderida kelloggii Kellogg's yampah
Phalaris aquatica* Harding grass
Phalaris minor* Little seed canarygrass
Phalaris paradoxa* Hood canarygrass
Plagiobothrys stipitatus var. stipitatus Popcorn flower Plantago lanceolata* Narrow leaf plantain
Pleuropogon californicus var. californicus Annual semaphoregrass Poa annua* Annual bluegrass
Polygonum aviculare* Common knotweed
Polypogon interruptus* Ditch beard grass
Polypogon monspeliensis* Rabbit's footgrass
Pseudognaphalium luteoalbum* Jersey cudweed
Psilocarphus brevissimus var. brevissimus Woolly marbles Ranunculus muricatus* Spiny-fruit butter cup
Raphanus raphanistrum* Jointed charlock
Raphanus sativa* Wild mustard
Rubus armeniacus* Himalayan berry
Rumex acetosella* Sheep sorrel
Rumex crispus* Curly dock
Rumex pulcher* Fiddle dock
1915
Scientific Name Common Name
List of Vascular Plants Observed in the Project
Salsola tragus* Russian tumbleweed
Senecio vulgaris* Common groundsel
Sisyrinchium bellum Western blue-eyed grass
Sonchus asper ssp. asper* Prickly sow thistle
Sonchus oleraceus* Common sow thistle
Stellaria media* Common chick-weed
Trifolium dubium* Shamrock clover
Trifolium hirtum* Rose clover
Trifolium subterraneum* Subterranean clover
Triglochin scilloides Flowering quillwort
Triphysaria versicolor ssp. faucibarbata Yellow owl's clover Typha angustifolia* Narrow leaf cattail
Veronica anagalis-aquatica* Water speedwell
Veronica peregrina spp. xalapensis Purslane speedwell
Vicia villosa ssp. villosa* Winter vetch
Xanthium strumarium Cocklebur
Zeltnera muehlenbergii Muehlenberg's centaury
* = non native
1916
Rare Plant Surveys Ph: (530) 633-0220
Giovannoni Logistics Center Project Fax: (530) 633-0230 APPENDIX C.

REPRESENTATIVE PHOTOGRAPHS
1917
Emergent marsh habitat within the northeastern corner
of wetland W88. Taken facing east on May 4, 2021.

Bermuda grass (Cynodon dactylon) dominated area within
northeastern edge of wetland W88. Taken facing east on
May 4, 2021.

Bermuda grass (Cynodon dactylon) dominated areas
(grayish color) within wetland W88. Taken facing west on May 4, 2021.

Grass and thatch dominating the non-wetland portions of the site. Taken facing north from wetland IW 1 on May 4, 2021.

Emergent marsh habitat within eastern edge of wetland
W90. Taken facing east on May 4, 2021.

The north end of Wetland W3 before going off site and
under the newly constructed bridge.
1918
Emergent marsh habitat within
eastern edge of wetland W90.

Taken facing north on April 7, 2021.

Wetland W3. Taken facing west
from west end of Wetland W2 on
April 7, 2021.

Wetland W3 close up. Taken facing
west from west on April 7, 2021.
1919
City of American Canyon—Giovannoni Logistics Center Project Draft EIR
FirstCarbon Solutions
Appendix D:

Cultural Resources and Tribal Cultural Resources Supporting Information
Appendix D contains sensitive information pertaining to cultural resources and has been withheld from public distribution pursuant to Public Resources Code, Sections 5097.9 and 5097.993. 1920

THIS PAGE INTENTIONALLY LEFT BLANK
1921
City of American Canyon—Giovannoni Logistics Center Project Draft EIR
FirstCarbon Solutions
Appendix E:

Geological Supporting Information
1922

THIS PAGE INTENTIONALLY LEFT BLANK
1923
Geotechnical Engineering Report

GREEN ISLAND ROAD LOGISTICS CENTER
WKA No. 12883.01
November 10, 2020
Prepared for:

Buzz Oates Management Services
555 Capitol Mall, Suite 900
Sacramento, California 95814
1924
Geotechnical Engineering Report

GREEN ISLAND ROAD LOGISTICS CENTER
WKA No. 12883.01

TABLE OF CONTENTS
INTRODUCTION ....................................................................................................................... 1 Scope of Services .......................................................................................................... 1 Figures and Attachments................................................................................................ 1 Proposed Development .................................................................................................. 2 Supplemental Information............................................................................................... 2 FINDINGS.................................................................................................................................. 3 Site Description .............................................................................................................. 3 Historical Aerial Photographic Review ............................................................................ 4 General Site Geology ..................................................................................................... 4 Subsurface Soil Conditions............................................................................................. 5 Groundwater................................................................................................................... 5 CONCLUSIONS......................................................................................................................... 6 Fault Rupture.................................................................................................................. 6 Soil Expansion Potential................................................................................................. 6 Liquefaction Potential ..................................................................................................... 7 Seismic Site Class.......................................................................................................... 8 2019 CBC/ASCE 7-16 Seismic Design Criteria .............................................................. 8 Bearing Capacity and Building Support .........................................................................10 Groundwater..................................................................................................................10 Seasonal Water.............................................................................................................10 Pavement Subgrade Quality..........................................................................................10 Excavation Conditions ...................................................................................................11 Soil Suitability for Use in Fill Construction......................................................................12 Permeability Characteristics of Near-Surface Soils........................................................12 Soil Corrosion Potential .................................................................................................13 RECOMMENDATIONS.............................................................................................................15 General .........................................................................................................................15 Site Clearing..................................................................................................................15 Site Preparation.............................................................................................................16 Engineered Fill Construction..........................................................................................17 Cut and Fill Slopes ........................................................................................................18 Utility Trench Backfill .....................................................................................................19 Foundations ..................................................................................................................20 1925
Geotechnical Engineering Report

GREEN ISLAND ROAD LOGISTICS CENTER
WKA No. 12883.01
TABLE OF CONTENTS (Continued)
Interior Floor Slabs ........................................................................................................21 Moisture Penetration Resistance...................................................................................23 Retaining Walls .............................................................................................................24 Exterior Flatwork ...........................................................................................................25 Site Drainage.................................................................................................................26 Pavement Design ..........................................................................................................27 Ancillary Foundations ....................................................................................................29 Site Drainage.................................................................................................................31 Drought Considerations.................................................................................................31 Geotechnical Engineering Observation and Testing During Earthwork Construction .....31 Additional Services........................................................................................................32 LIMITATIONS ...........................................................................................................................32

FIGURES
Vicinity Map..........................................................................................................Figure 1 Site Plan...............................................................................................................Figure 2 Logs of Soil Borings..........................................................................Figures 3 through 54 Unified Soil Classification System.......................................................................Figure 55 APPENDIX A - General Project Information, Field and Laboratory Test Results Atterberg Limits Test Results.......................................................... Figures A1through A4 Expansion Index Test Results ....................................................... Figures A5 through A9 Resistance Value Test Results.................................................. Figures A10 through A12 Hydraulic Conductivity Test Results ................................................ Figures A13 and A14 Soil Corrosion Test Results ....................................................... Figures A15 through A26 Compaction Curve Test Results ...................................................... Figures A27 and A28 APPENDIX B – Guide Earthwork Specifications
1926
Geotechnical Engineering Report

GREEN ISLAND ROAD LOGISTICS CENTER
Green Island Road
American Canyon, California
WKA No. 12883.01
November 10, 2020

INTRODUCTION
As authorized, we have completed a geotechnical engineering study for the proposed Green Island Road Logistics Center to be constructed north of Green Island Road in American Canyon, California (see Figure 1). The purposes of this study have been to explore the existing site, soil, and groundwater conditions across the site, and to provide geotechnical engineering conclusions and recommendations for use by the other members of the design team in design and construction of the proposed industrial development. This report presents the results of our study.

Scope of Services
Our scope of services for this project has included the following tasks:

1. Site reconnaissance;

2. Review of previous geotechnical studies that included the project site and for a property within the near vicinity of the site;

3. Review of United States Geological Survey (USGS) topographic maps, historical aerial photographs and available groundwater information;

4. Subsurface explorations, including the drilling and sampling of 52 borings to depths ranging from approximately 10 to 31½ feet below the existing site grades;

5. Collection of representative bulk samples of near-surface soils;

6. Laboratory testing of selected soil samples;

7. Engineering analyses; and,

8. Preparation this report.

Figures and Attachments
This report contains a Vicinity Map as Figure 1; a Site Plan showing the approximate boring exploration locations as Figure 2; and, Logs of Soil Borings as Figures 3 through 54. An explanation of the symbols and classification system used on the logs is included as Figure 55.

Appendix A contains general information regarding project concepts, exploratory methods used 1927
Geotechnical Engineering Report Page 2

GREEN ISLAND ROAD LOGISTICS CENTER
WKA No. 12883.01
November 10, 2020
during our field investigation, and laboratory test results not included on the boring logs.

Appendix B contains Guide Earthwork Specifications that may be used in preparation of contract documents.

Proposed Development
Based on conversations with Mr. Joe Lavaich of Buzz Oats; review of Preliminary Concept Site Plan prepared by RMW Architecture Interiors dated August 8, 2020, we understand the proposed logistics center will include the construction of six warehouse/office buildings identified as Buildings A through F. The warehouse/office structures will encompass building footprints ranging from about 188,300 square feet (sf) up to 715,500 sf. We anticipate that the structures will be constructed of concrete tilt-up panels with interior concrete slabs-on-grade floors. Below grade basements are not anticipated. Structural loads for the buildings are anticipated to be heavy on the order of 150 kips for interior column loads and about 5 kips per lineal foot for exterior walls. Associated improvements will include the construction of underground utilities, landscaping, exterior flatwork, below-grade loading docks, retaining walls, asphalt pavements, and two storm water retention ponds. We anticipate that the storm water retention ponds will be about 5 to 10 feet in depth with unlined side slope gradients of three horizontal to one vertical (3H:1V) or flatter.

Grading plans were not available; however based on the existing site topography, we anticipate maximum excavations and fills on the order of one to five feet for development of the logistics center.

Supplemental Information
Supplemental information used in the preparation of this report included review of the following reports prepared by others and Wallace-Kuhl and Associates (WKA) for studies that included the site and for properties near the project site:
• Cornerstone Earth Group, 2017, Geologic Fault Investigation New Sanitary Sewer Main prepared for the Giovanni Property which is located within the site, Project No. 582-4-1; • Wallace-Kuhl & Associates, Inc., 1994, Geotechnical Engineering Report prepared for Lot 5 of the Green Island Industrial Park, WKA No. 2652.02, March 1994; • Wallace-Kuhl & Associates, Inc., 1994, Geotechnical Engineering Report prepared for the Graton Beverage Facility located on Lot 15 of the Green Island Industrial Park, WKA No. 2651.01, April 1994;
1928
Geotechnical Engineering Report Page 3

GREEN ISLAND ROAD LOGISTICS CENTER
WKA No. 12883.01
November 10, 2020
• Wallace-Kuhl & Associates, Inc., 1995, Geotechnical Engineering Report prepared for Spec Buildings 59 and 188 of the Green Island Industrial Park, WKA No. 2651.04, May 1995;
• Wallace-Kuhl & Associates, Inc., 1996, Preliminary Geotechnical Engineering Report prepared for Mezzetta Court Spec Building 197 of the Green Island Industrial Park, WKA No. 3142.01, February 1996;
• Wallace-Kuhl & Associates, Inc., 1996, Geotechnical Engineering Report prepared for Mezzetta Court Spec Building 90 of the Green Island Industrial Park, WKA No. 3296.01, September 1996;
• Wallace-Kuhl & Associates, Inc., 1998, Geotechnical Engineering Report prepared for Spec Building 102 of the Green Island Industrial Park, WKA No. 3744.01, July 1998; • Wallace-Kuhl & Associates, Inc., 1998, Geotechnical Engineering Report prepared for Spec Building 91 on Lot 3 of the Green Island Industrial Park, WKA No. 3745.01, July 1998;
• Wallace-Kuhl & Associates, Inc. 2000, Geotechnical Engineering Report prepared for the Sutter Home Distribution Center Expansion located within the Green Island Industrial Park, WKA No. 4408.01, May 2000;
• Wallace-Kuhl & Associates, Inc, 2005, Geotechnical Engineering Report prepared for the Yandell Warehouse located within the Green Island Industrial Park, WKA No. 6445.02, March 2005; and,
• Wallace-Kuhl & Associates, Inc., 2008, Geotechnical Engineering Report prepared for the Biagi Brothers Wine Distribution Center located adjacent to the west of the subject property, WKA No. 8005.01, March 2008.

FINDINGS
Site Description
The project site is located north of Green Island Road and about a quarter mile west of Highway 29 in American Canyon, California and encompasses a total area of approximately 208-acres.

The site occupies land identified as Napa County Assessor Parcel Numbers 057-130-034, -036, and -038. The site is bounded to the north by commercial and industrial developments, beyond which is the Napa County Airport; to the east by Union Pacific Railroad lines, beyond which is commercial and industrial developments; to the south by commercial and industrial developments, Green Island Road, and Union Pacific Railroad lines; and, to the east by commercial and industrial developments.
1929
Geotechnical Engineering Report Page 4

GREEN ISLAND ROAD LOGISTICS CENTER
WKA No. 12883.01
November 10, 2020
The topography of the site is sloping gently from southeast to northwest. The highest portion of the site, the farthest southeast area, has a maximum surface elevation of about +55 feet msl and the lowest portion of the site, the farthest northwest area, has a surface elevation of about +25 feet msl, based on topographic information shown on the USGS 7.5-Minute Topographic Map of the Cuttings Wharf Quadrangle, California, dated 2018.

A drainage swale, dry at the time of our explorations, runs from north to south within the western portion of the site, a portion of this drainage swale is diverted through a large diameter pipe that is covered by soil to allow vehicle access between the two sides of the swale. The swale is approximately two feet deep.

At the time of our field explorations, performed between September 21, 2020, and October 2, 2020, the site was vacant pasture land covered with grassy low-lying vegetation.

Historical Aerial Photographic Review
We reviewed historical aerial photographs of the site available from our files and the Google Earth software. Available photographs were taken in the years 1948, 1958, 1968, 1982, 1993 and 2002 through 2020.

Review of the photographs taken from 1948 through 2020 show the site was an agricultural fallow area used for livestock grazing. A seasonal creek located in the northwest portion of the site trends in a northwest-west direction. There are three east-west trending smaller tributaries to the creek along the northern property line and about 200 and 350 feet south of the northern property line, and a north-south trending tributary approximately 1400 feet east of the western property line. Seasonal wetland depressions are observed throughout the site throughout each year. The locations of observed wetlands, are shown on the Site Plan, Figure 2.

General Site Geology
The site is located in the southern portion of Napa Valley which is characterized as a relatively large north-west tending alluvial valley located within the Northern California Coast Range geomorphic province. Various authors have mapped the local geology of the site area. These maps differ in scale and detail but agree that a majority site as being underlain by the late Pleistocene to Holocene age alluvial fan deposits (Qf) [Bezore, et al., 2002], which are bound to the north and west by older geologic units including Late Pleistocene fan deposits (Qpf) and early to middle Pleistocene alluvial fan and terrace deposits (Qoa). The Qf unit is relatively younger than and was deposited over the Qpf and Qoa units. The Qf unit is described as gently sloping, fan-shaped alluvial surfaces. Sediments include sand, gravel, silt and clays that are moderately to poorly sorted and moderately to poorly bedded. The Qpf unit is described as 1930
Geotechnical Engineering Report Page 5

GREEN ISLAND ROAD LOGISTICS CENTER
WKA No. 12883.01
November 10, 2020
gently sloping, fan-shaped alluvial surfaces where late Pleistocene age is indicated by slight dissection and/or the development of alfisols. The Qoa unit is described as moderately to deeply dissected alluvial deposits capped by alfisols, ultisols, or soils containing a silica or calcic hardpan.

The western portion of the site is mapped as Huichica Formation (QTh), part of the Sonoma Assemblage, of early Pleistocene and Pliocene age. The formations is described as fluvial gravel, sand, silt and clay.

Subsurface Soil Conditions
A total of 52 borings (D1 – D52) were performed at the site between September 21, 2020, and October 2, 2020. The approximate locations of the explorations are shown on the Site Plan, Figure 2. We also collected bulk samples of surficial soils at three locations within proposed pavement areas (B1 – B3).

The borings reveal the surface and near-surface soil conditions at the site consist of moderate to high plastic, stiff to hard, lean clay to depths about five to 10 feet below the existing ground surface (bgs). Underlying the upper clay soil were interbedded silty lean clays, sandy lean clays, clayey sands and silty sands to the maximum depth explored of 51½ feet bgs. The surface and near-surface soils across the site were observed to be relatively loose with frequent desiccation cracks to depths of about 6 to 18 inches.

The soil conditions encountered in the explorations for this study are consistent with soil conditions encountered in previous studies referenced in this report. For specific information regarding the soil conditions at a specific exploration location, please refer to the Logs of Soil Borings, Figures 3 through 54.

Groundwater
Groundwater was encountered in six of the 52 borings performed during our field work, at depths ranging from approximately 12 to 20 feet bsg. The borings were backfilled with neatcement grout as required by the Napa County upon completion of the subsurface exploration program. Please note that the borings may not have been left open long enough for groundwater to reach static equilibrium.

To supplement the groundwater data obtained from the borings, we reviewed available groundwater information at the California Department of Water Resources (DWR) website. The DWR periodically monitors groundwater levels in wells across the state. Their website shows one well located near the sites border with the commercial and industrial development near the 1931
Geotechnical Engineering Report Page 6

GREEN ISLAND ROAD LOGISTICS CENTER
WKA No. 12883.01
November 10, 2020
middle of the site. The well is identified as Well No. 04N04W13E001M with ground surface elevations of about +44 feet msl, which is similar to the elevation at the project site.

Groundwater data for this well was recorded from March 25, 1930 to at least April 18, 1962.

Data shows the highest recorded groundwater depth at the well was about +33.5 feet msl (about 10.5 feet below the ground surface) at the well on March 28, 1952. The lowest recorded groundwater elevation was about +21.4 feet msl at the well (about 22.6 feet below the ground surface) at the well on September 6, 1961.

These groundwater conditions are consistent with the groundwater levels observed during the field explorations performed for this study. Similar groundwater can be expected during the proposed construction.

CONCLUSIONS
Fault Rupture
According to mapping by the California Geologic Survey, the western portion of the project site lies within a mapped Earthquake Fault Zone and Seismic Hazard Zone. In 2017, a geologic fault investigation was performed by the Cornerstone Earth Group to locate the potential surface trace of the West Napa Fault as part of a proposed sewer main alignment project. The investigation included a review of previously completed investigations performed by other consultants to locate and/or “clear” sites of fault surface traces, drilling an array of borings, and excavating three observation trenches along the suspected fault alignment. The West Napa Fault was confirmed as trending through the western portion of the project site. The approximate fault trace is shown on the Site Plan, Figure 2.

Further evaluation for the presence or absence of the West Napa Fault or the potential for fault rupture is beyond our scope of services for this project. The referenced Cornerstone Earth Group report should be submitted to the local building official to satisfy the requirements of the Alquist Priolo Fault Hazard Zone Act, if required.

Soil Expansion Potential
Laboratory testing of three representative near-surface clay soil samples collected from the proposed building footprint revealed these soils possess moderate to high plasticity when tested in accordance with the American Society of Testing and Materials (ASTM) D4318 test method (see Figures A1 through A4). Laboratory test results of the five near-surface clay soil samples also revealed these soils possess Expansion Indices ranging from 33 to 108, equivalent to a “low to high” expansion potential when tested in accordance with the ASTM D4829 test method 1932
Geotechnical Engineering Report Page 7

GREEN ISLAND ROAD LOGISTICS CENTER
WKA No. 12883.01
November 10, 2020
(see Figures A5 through A9). These results are consistent with testing performed on nearby sites.

Based on these test results, the test results from previous studies referenced in this report and our local experience, the near-surface clay soils at the site are considered capable of exerting significant expansion pressures on building foundations, interior floor slabs, exterior flatwork, and pavements. In our opinion, the near surface soils supporting slab on grade concrete will require removal and replacement with imported, non-expansive soils (Expansion Index < 20), or chemical amendment of the clay soils (i.e., lime-treatment) to reduce the expansion potential of the near surface clays.

Liquefaction Potential
A common secondary hazard as a result of strong ground shaking is the potential for soil liquefaction and subsidence. Liquefaction describes a phenomenon in which saturated soil in the upper 40 to 50 feet of subgrade loses shear strength and deforms as a result of increased pore water pressure induced by strong ground shaking. As the excess pore pressures dissipate following an earthquake, volume changes within the liquefied soil layer will occur, which can manifest as ground surface settlement, ground rupture (sand boils or ground cracking), and lateral slope displacement (commonly referred to as lateral spreading). Soils most susceptible to liquefaction are saturated, loose to medium dense sand and silt or clay with plasticity indices (PI) less than 12 and moisture contents greater than 85 percent of the soils liquid limit (LL) (Bray and Sancio, 2006).

A preliminary screening suggests that a majority of the subsurface soils encountered during our investigation were generally too high in plasticity (i.e., clay) and/or too stiff/dense to be susceptible to liquefaction. Strata of silty sand, clayey sand and poorly graded “clean” sand, however, was encountered at borings D21 and D32 at depths of about 30 feet below the ground surface (bgs). Accordingly, a liquefaction analysis was performed in accordance with an approach outlined by the National Center for Earthquake Engineering Research (NCEER) and summarized by Youd, et al (2001). A groundwater depth of 12 feet (corresponding to the estimated high groundwater depth encountered), a peak ground acceleration adjusted for site class effects (PGAM) of 0.98g based on a return period of 2,475 years (2% probability of exceedance in 50 years), and a mode magnitude earthquake of 6.9 was used in the analysis.

The mode magnitude earthquake was determined using the using the 2014 USGS National Seismic Hazard Mapping Project (NSHMP) Probabilistic Seismic Hazard Analysis (PSHA) Interactive Deaggregation website.
1933
Geotechnical Engineering Report Page 8

GREEN ISLAND ROAD LOGISTICS CENTER
WKA No. 12883.01
November 10, 2020
The results of our analysis suggest that strata of silty and poorly graded sands with penetration resistance (N-value) less than 30 blows per foot (bpf) and clayey sands with N-values less than about 20 bpf are potentially susceptible to liquefaction. Using empirical procedures (Ishihara and Yoshimine 1992), the seismically-induced settlement at the top of the liquefiable sand layers is estimated to range from about ¾ inch to 2 inches. This liquefaction is not expected to be widespread since the potentially liquefiable soil layers appear to be discontinuous and confined. Furthermore, ground surface settlement should be significantly less due to bridging effects within the overlying soil. Typical practice for these conditions is to assume a localized differential settlement on the order of one-half of the total estimated settlement to account for soil variability and engineering uncertainties. In our opinion, the anticipated maximum differential settlement due to liquefaction should be on the order of 1 inch over a horizontal distance of 100 feet.

The methods used to estimate liquefaction settlement assume that there is a sufficient cap of non-liquefiable material to prevent ground cracking or sand boils. For ground rupture to occur, the excess pore water pressure within the liquefiable soil layer needs to be great enough to break through the overlying non-liquefiable soil layer, which could cause additional ground deformation and settlement. The work of Youd and Garris (1995) indicates that the potentially liquefiable soils are overlain by a sufficient cap of non-liquefiable soil to prevent ground rupture; therefore the above total settlement estimates appear to be reasonable.

Seismic Site Class
Based on the soil conditions encountered at the exploration locations and our experience with similar soil conditions in the vicinity of the site, it is our opinion that the soils at the project site are not vulnerable to potential failure or collapse under seismic loading and can be designated as Site Class D in determining seismic design forces for this project in accordance with Section 1613A.3.2 of the 2013 CBC, which references Chapter 20 of American Society of Civil Engineers (ASCE) Standard 7-10. While relatively thin discrete layers of granular soils have been determined to be liquefiable, these layers appear to be discontinuous and confined.

Furthermore, the estimated cumulative seismically induced settlement is relatively small (about 1 inch or less). In our opinion, the stiff clay soil profile under the site will control the seismic behavior of the soil in a seismic event.
2019 CBC/ASCE 7-16 Seismic Design Criteria
The 2019 CBC references the ASCE Standard 7-16 for seismic design. The following seismic parameters provided in Table 1 were determined based on the site latitude and longitude and the web interface developed by the Structural Engineers Association of California (SEAOC) and 1934
Geotechnical Engineering Report Page 9

GREEN ISLAND ROAD LOGISTICS CENTER
WKA No. 12883.01
November 10, 2020
the California Office of Statewide Health Planning and Development (OSHPD) (https://seismicmaps.org).

Since S1 is greater than 0.2 g, a ground motion hazard analysis will be required (Section 11.4.8 of the 2019 CBC) in accordance with Section 21.2 of ASCE 7-16. However, if Exception Note No. 2 in Section 11.4.8 of ASCE 7-16 applies (specifically if T≤ 1.5 x Ts), the 2019 CBC coefficient values Fv, SM1, and SD1 presented in Table 1 below are valid for this project. Further evaluation of the seismic design parameters presented in Table 1, including the seismic Site Class will be required during preparation of the design-level geotechnical report.

The seismic design parameters summarized below in Table 1 may be used for seismic design of the planned improvement at the site.

TABLE 1 – 2019 CBC/ASCE 7-16 SEISMIC DESIGN PARAMETERS
Latitude: 38.1993° N
Longitude: 121.2670° W
ASCE 7-16
Table/Figure
2019 CBC
Figure/Section/Table
Factor/
Coefficie
2019
CBC

0.2-second Period MCE Figure 22-1 Figure: 1613.2.1(1) SS 2.156 g

1.0 second Period MCER Figure 22-2 Figure: 113.2.1(2) S1 0.780 g Soil Class Table 20.3-1 Sections: 1613.2.2 Site
Class D
Site Coefficient Table 11.4-1 Tables: 1613.2.3 (1) Fa 1.000 Site Coefficient Table 11.4-2 Tables: 1613.2.3(2) Fv 1.700* Adjusted MCE Spectral
Response Parameters
Equation 11.4-1 Equations: 16-36 SMS 2.156 g
Equation 11.4-2 Equations: 16-37 SM1 1.326 g*
Design Spectral
Acceleration Parameters
Equation 11.4-3 Equations: 16-38 SDS 1.437 g
Equation 11.4-4 Equations: 16-39 SD1 0.884 g*
Seismic Design Category
Table 11.6-1 Tables: 1613.2.5(1)
Risk
Category
I to IV
D
Table 11.6-2 Tables: 1613.2.5(2)
Risk
Category
I to IV
D
Notes: MCER = Risk-Targeted Maximum Considered Earthquake; g = gravity * = The value is valid if the requirements in Exception Note No. 2 in Section 11.4.8 of ASCE 7-16 are met. If not, a ground motion hazard analysis will be required (Section 11.4.8 of the 2019 CBC) in accordance with Section 21.2 of ASCE 7-16
1935
Geotechnical Engineering Report Page 10

GREEN ISLAND ROAD LOGISTICS CENTER
WKA No. 12883.01
November 10, 2020
Bearing Capacity and Building Support
The subgrade soils encountered generally consist of stiff to hard, low compressible clay that should provide adequate support for the anticipated structural loading provided the recommendations in this report are followed. The surface and near-surface soils across the site were relatively loose and had frequent desiccation cracks ranging from about 6 to 18 inches in depth. Accordingly, these soils should be deep ripped or scarified, moisture conditioned, and compacted in-place prior construction and/or placement of engineered fill.

Groundwater
Groundwater was encountered in six of the 52 borings drilled during our field explorations, at depths ranging from approximately 12 to 20 feet below existing site grades. Review of available groundwater data revealed groundwater depths at the site likely fluctuated from about 10½ to 22 feet bgs.

Groundwater levels at the site should be expected to fluctuate throughout the year based on variations in seasonal precipitation, time of year, tidal fluctuations, local irrigation practices, and the proximity to drainage canals/ditches.

Based on explorations performed at the site and available groundwater data, we anticipate excavations extending below 10 feet below the ground surface may encounter groundwater and require dewatering (depending on the time of year).

Seasonal Water
During the wet season, infiltrating surface runoff water will create a saturated surface condition due to the relatively low permeability of the near-surface soils. It is probable that grading operations attempted following the onset of winter rains and prior to prolonged drying periods will be hampered by high soil moisture contents. Such soil, intended for use as engineered fill, will require a prolonged period of dry weather and/or considerable aeration to reach a moisture content that allows achieving the required compaction. This should be considered in the construction schedule for the project.

Pavement Subgrade Quality
Laboratory test results performed on three representative bulk samples of near-surface clay soils from proposed pavement areas of the site revealed these soils will provide poor support characteristics for pavements. Accordingly, relatively thick pavement sections are required to compensate for the lower support characteristics of these soils. Laboratory test results revealed 1936
Geotechnical Engineering Report Page 11

GREEN ISLAND ROAD LOGISTICS CENTER
WKA No. 12883.01
November 10, 2020
the clay soil possess a Resistance ("R") value of 5 when tested in accordance with California Test 301 (see Figures A10 through A12). Based on our findings and previous experience in the project area, it is our opinion an R-value of 5 is appropriate for design of pavements at the site supported on untreated subgrade soil.

In lieu of supporting pavement directly on expansive clay, pavement sections are also presented assuming the upper 12 inches of subgrade soil is amended by mixing it with lime (limetreatment). This procedure strengthens and reduces the plasticity/expansion characteristics of the treated clay and, thus, tends to reduce future maintenance and associated costs.

Furthermore, the required aggregate base section is thinner for pavement supported on lime treated soil, thus reducing the relative cost of the lime-treatment.

The performance of lime stabilized soils is dependent on uniform mixing of the quicklime into the subgrade soils, and providing a proper curing period following compaction. An experienced soil stabilization contractor, combined with a comprehensive quality control program, is essential to achieve the best results with lime stabilized soils.

Representative near-surface clay soils from proposed pavement areas of the site were mixed with four percent dolomitic quicklime and subjected to an R-value test. Laboratory test results revealed the treated clay soils possess an R-value of 82, 84, and 84 when tested in accordance with California Test 301 (see Figures A10 through A12). Based on the Caltrans Highway Design Manual, a maximum R-value of 50 should be used for design of pavements to be supported on a treated subgrade. Therefore, an R-value of 50 is appropriate for design of pavements at the site supported on treated surface and near-surface sand lean clay soils.

Additional recommendations regarding lime-treatment of the pavement subgrade soils are provided in the Pavement Design section of this report.

Excavation Conditions
The surface and near-surface soils at the site should be readily excavated using conventional earthmoving and trenching equipment. Shallow excavations (less than 5-feet deep) in the clay encountered should stand vertically for a period long enough for typical foundation and utility, unless they become wet or are disturbed. The sand encountered, however, is cohesionless and may cave and/or slough soon after it is exposed in the excavation. Where encountered, the contractor should be prepared to brace or shore the excavations, as necessary.

Temporarily sloped excavations and shored excavations less than 20 feet in depth should be constructed in accordance with federal, local and OSHA standards (29 CFR Part 1926) under the guidance of the Contractors qualified “competent person.” For preliminary evaluation, the silts and clays encountered would classify as Cal-OSHA Type B soil, while the sands would 1937
Geotechnical Engineering Report Page 12

GREEN ISLAND ROAD LOGISTICS CENTER
WKA No. 12883.01
November 10, 2020
classify as Type C soils. In no case should the information provided be interpreted to mean that Wallace-Kuhl & Associates is assuming responsibility for site safety or the Contractor’s activities.

Excavated materials should not be stockpiled directly adjacent to an open excavation to prevent surcharge loading of the excavation sidewalls. Excessive truck and equipment traffic should be avoided near excavations. If material is stored or heavy equipment is stationed and/or operated near an excavation, a shoring system must be designed to resist the additional pressure due to the superimposed loads.

Soil Suitability for Use in Fill Construction
The existing on-site soils, including the fill soils, are considered suitable for use as engineered fill, if they do not contain significant quantities of organics, rubble and deleterious debris, and are at a proper moisture content to achieve the desired degree of compaction. Organically laden topsoil should not be reused as engineered fill.

During the wet season, infiltrating surface runoff water will create a saturated surface condition due to the relatively low permeability of the near-surface soils. It is probable that grading operations attempted following the onset of winter rains and prior to prolonged drying periods will be hampered by high soil moisture contents. Such soil, intended for use as engineered fill, will require a prolonged period of dry weather and/or considerable aeration to reach a moisture content that allows achieving the required compaction. This should be considered in the construction schedule for the project.

Permeability Characteristics of Near-Surface Soils
The soils encountered in the area of the proposed detention ponds (borings D10, D11, D12, D18, D37, D43, D44, and D45) generally consisted of moderate to high plastic clay to depths ranging from about five to greater than 10 feet bgs, followed by silty and clayey sand. To assist in determining the permeability characteristics of the clays underlying the site, two laboratory hydraulic conductivity (ASTM D5084) tests were performed on relatively undisturbed soil samples obtained from borings D12 and D44. The results showed that the soil had permeability rates of about 9.8x10-9 and 1.7x10-6 centimeters per second (cm/sec.). The results are presented in Figures A13 and A14. Based on our previous experience, when compacted the permeability of these clays could be expected to be 1x10-7 cm/sec. or slower. Based on various publications (Hazen1
, Aryani2 and Das3) and previous experience, for preliminary design a 1 Allen Hazen, Some Physical Properties of Sand and Gravels, with Special Reference to their Use in Filtration, (Massachusetts: State Board of Health, 1892).
1938
Geotechnical Engineering Report Page 13

GREEN ISLAND ROAD LOGISTICS CENTER
WKA No. 12883.01
November 10, 2020
permeability rate of between 1x10-4 and 1x10-5 cm/sec can be anticipated for the silty and clayey sands encountered, respectively.

Depending on their final depths, we anticipate the ponds may need to be lined with clay to improve their “water-holding” capacity. The liner, if constructed, should be designed by the project Civil Engineer. As previously discussed, the native clays are moderate to highly plastic and may exhibit significant shrinking and cracking during warm weather conditions when the retention ponds are dry. When the ponds are again filled, the infiltration characteristics of the ponds could be affected for a period of time. If the native clay or a clay liner will be exposed within the ponds, consideration should be given to overlying the clays with a 12 to 18 inch thick layer of low plasticity silt or sand to reduce moisture fluctuations or by reducing the plasticity of the clay by intermixing or blending the soils with a low plasticity soils. If blending is considered, laboratory tests should be performed to evaluate the permeability of the mixed soil. If requested, WKA can provide additional criteria for either of these alternatives.

Soil Corrosion Potential
The samples of representative, near-surface clay soil was submitted to Sunland Analytical Lab of Rancho Cordova, California for laboratory testing to determine minimum resistivity, pH, and chloride and sulfate concentrations to help evaluate the potential for corrosive attack upon reinforced concrete and buried metal. The results of the corrosivity testing are summarized in Table 2; copies of the corrosion test reports are presented in Figures A15 through A26.

Table 2a: Corrosion Test Results
Analyte Test Method D6 (0’-5’) D14 (0’-5’) D22 (0’-5’)
pH CA DOT 643 Modified* 6.48 6.89 5.41
Minimum
Resistivity CA DOT 643 Modified* 540 Ω-cm 220 Ω-cm 880 Ω-cm Chloride CA DOT 422 323.0 ppm 758.8 ppm 61.6 ppm
Sulfate CA DOT 417 167.4 ppm 821.2 ppm 185.2 ppm
Sulfate-SO4 ASTM D-516m 179.4 mg/kg 783.1 mg/kg 194.2 mg/kg

2 Cyrus Aryani, Applied Soil Mechanics and Foundation Engineering, Volume 1 (California State University, Sacramento, Aryani, 2004)
3 Braja M. Das, Fundamentals of Geotechnical Engineering, Second Edition (Ontario: Thomas Learning, Stenquist, 2005).
1939
Geotechnical Engineering Report Page 14

GREEN ISLAND ROAD LOGISTICS CENTER
WKA No. 12883.01
November 10, 2020
Table 2b: Corrosion Test Results (cont.)
Analyte Test Method D33 (0’-5’) D40 (0’-5’) D49 (0’-5’) pH CA DOT 643 Modified* 5.78 6.77 6.72
Minimum
Resistivity CA DOT 643 Modified* 380 Ω-cm 640 Ω-cm 1,070 Ω-cm Chloride CA DOT 422 379.7 ppm 374.8 ppm 9.0 ppm
Sulfate CA DOT 417 443.5 ppm 295.9 ppm 3.0 ppm
Sulfate-SO4 ASTM D-516m 493.8 mg/kg 313.5 ppm 3.1 ppm
Notes:
* = Small cell method CA DOT = California Department of Transportation Ω-cm = Ohm-centimeters ppm = Parts per million
The California Department of Transportation Corrosion and Structural Concrete Field Investigation Branch, Corrosion Guidelines, Version 2.1, dated January 2015, considers a site to be corrosive to foundation elements if one or more of the following conditions exists for the representative soil and/or water samples taken: has a chloride concentration greater than or equal to 500 ppm, sulfate concentration greater than or equal to 2000 ppm, or the pH is 5.5 or less. Based on this criterion, areas of the on-site, near-surface clay soil are considered unusually corrosive to steel reinforcement properly embedded within PCC for the samples tested. The low resistivity may indicate a higher corrosion potential to metal in direct contact with soil. Based on the chloride concentration criterion, the surface and near-surface clay soils tested can lead to corrosion of steel reinforcement in concrete and steel structures by breaking down the protective layer of oxides normally present on the steel surface.

Caltrans indicates soil or water with a pH of 5.5 or less can react with the lime in concrete to form soluble reaction products that can more easily leach out of the concrete. This is of special concern where the sulfate concentrations in the soil are above 2,000 ppm, as the more brittle concrete (caused by the leaching of soluble reaction products) can be more susceptible to cracking which can allow for sulfate attack of the rebar reinforcement. Test results indicate a maximum sulfate concentration of 821.2 ppm at the site, which is well below the 2,000 ppm threshold. Acidic (low pH) conditions also can cause discoloration resulting in a yellowish or rust color distributed over the concrete surface. Considering the low sulfate concentrations, we do not anticipate the low pH of the soils to be a significant factor in development of the property.

Table 19.3.1.1 – Exposure Categories and Classes, of American Concrete Institute (ACI) 318- 14, Section 19.3 – Concrete Design and Durability Requirements, as referenced in Section 1904.1 of the 2016 CBC, indicates the severity of sulfate exposure for the samples tested is Exposure Class S0 (water-soluble sulfate concentration in contact with concrete is low and 1940
Geotechnical Engineering Report Page 15

GREEN ISLAND ROAD LOGISTICS CENTER
WKA No. 12883.01
November 10, 2020
injurious sulfate attack is not a concern). The project structural engineer should evaluate the requirements of ACI 318-14 and determine their applicability to the site.

Wallace-Kuhl & Associates are not corrosion engineers. Therefore, if it is desired to further define the soil corrosion potential at the site a corrosion engineer should be consulted.

RECOMMENDATIONS
General
The recommendations presented below are appropriate for typical construction in the late spring through fall months. The on-site soils likely will be saturated by rainfall in the winter and early spring months, and will likely not be compactable without drying by aeration or chemical treatment. Should the construction schedule require work to continue during the wet months, additional recommendations can be provided, as conditions dictate.

Relative compaction should be based on the maximum dry density as determined in accordance with the ASTM D1557 Test Method.

Site preparation should be accomplished in accordance with the provisions of this report and the appended specifications. A representative of the Geotechnical Engineer should be present during all earthwork operations to evaluate compliance with the recommendations and the guide specifications included in this report. The Geotechnical Engineer of Record referenced herein should be considered the Geotechnical Engineer that is retained to provide geotechnical engineering observation and testing services during construction.

Site Clearing
Prior to grading, the planned construction areas should be cleared of all surface trash, rubble, and deleterious debris, if any, to expose firm and stable soils, as determined by the Geotechnical Engineer’s representative. The area of removal should extend at least five feet beyond the edge of all exterior flatwork and pavements, where practical. Any rubble and debris, if encountered, should be removed from the site.

Any existing underground utilities designated to be removed or relocated from the site should include removal of all trench backfill and bedding materials. The resulting excavations should be restored with engineered fill placed and compacted in accordance with the recommendations included in this report.
1941
Geotechnical Engineering Report Page 16

GREEN ISLAND ROAD LOGISTICS CENTER
WKA No. 12883.01
November 10, 2020
Surface vegetation/organics and organically laden soil within construction areas should be stripped from the site. Debris from the stripping operations should not be used in general fill construction areas supporting concrete slabs, pavements or any other surface improvements.

Discing of the organics into the surface soils may be a suitable alternate to stripping, depending on the condition and quantity of the organics at the time of grading. The decision to utilize discing in lieu of stripping should be made by the Geotechnical Engineer, or his representative, at the time of earthwork construction. Discing operations, if approved, should be observed by the Geotechnical Engineer’s representative, and be continuous until the organics are adequately mixed into the surface soils to provide a compactable mixture of soil containing minor amounts of organic matter. Pockets or concentrations of organics will not be allowed.

Any depressions resulting from site clearing operations, as well as any loose, soft, disturbed, saturated, or organically contaminated soils, as identified by the Geotechnical Engineer’s representative, should be cleaned out to firm, undisturbed soils and backfilled with engineered fill in accordance with the recommendations of this report. It is important that the Geotechnical Engineer’s representative be present during clearing operations to verify adequate removal of any surface and subsurface items, as well as the proper backfilling of resulting excavations.

Site Preparation
The near-surface soil underlying the site consists of moderate to highly plastic clay that, based on our experience and testing, can exhibit significant expansion characteristics. The following presents recommendations for general subgrade preparation. Subsequent sections should be reviewed for specific or supplemental recommendations to address the expansive soil conditions.

The surface and near-surface soils encountered during our investigation were relatively loose with frequent desiccation cracks. Furthermore, we anticipate that clearing operations will likely cause additional disturbance to the upper soils. Therefore, in all areas that will support concrete slabs, engineered fill or pavement, should be thoroughly scarified to a depth of at least 12 inches, brought to a uniform moisture content at least two percentage point above the optimum moisture content, and compacted to not less than 90 percent of the maximum dry density per ASTM D1557 specifications. In pavement areas, the relative compaction of the upper 6 inches of final soil subgrade should be increased to 95 percent of the maximum dry density.

The performance of pavement is critically dependent upon uniform and adequate compaction of the soil subgrade, as well as all engineered fill and utility trench backfill within the limits of the pavements. Final pavement subgrade preparation (i.e. scarification, moisture conditioning and compaction) should be performed after underground utility construction is completed and just prior to aggregate base placement.
1942
Geotechnical Engineering Report Page 17

GREEN ISLAND ROAD LOGISTICS CENTER
WKA No. 12883.01
November 10, 2020
Pavement subgrades should be stable and unyielding under heavy wheel loads of construction equipment. To help identify unstable subgrades within the pavement limits, a proof-roll should be performed with a fully-loaded, water truck on the exposed subgrades prior to placement of aggregate base. The proof-roll should be observed by the Geotechnical Engineer’s representative.

If construction begins during the summer or fall, there is a potential that the surface clayey soils may be desiccated deeper than the recommended depth of scarification. Should this condition exist, the site should be continuously watered for a sufficient period of time to close the desiccation cracks.

The prepared subgrade soils should be protected from disturbance until covered by capillary break material or aggregate base. Disturbed subgrade soils may require additional processing and recompaction just prior to construction of these improvements, depending on the level of disturbance.

All subgrade preparation must be performed in the presence of the Geotechnical Engineer’s representative who will evaluate the performance of the subgrade under compaction loads and identify any loose or unstable soil conditions that could require remediation. Construction bid documents should contain a unit price (price per cubic foot) for additional excavation due to unsuitable materials and replacement with engineered fill.

Engineered Fill Construction
Engineered fill consisting of on-site or import materials should be placed in lifts not exceeding six inches in compacted thickness, with each lift being thoroughly moisture conditioned to at least two percent above the optimum moisture content for clay soils and to the optimum moisture content for granular/silty soils (import fill materials). Soils should be uniformly compacted to at least 90 percent relative compaction.

On-site soils encountered in our explorations are considered suitable for use as engineered fill, provided they are at a workable moisture content to achieve required compaction, and do not contain rubbish, rubble, deleterious debris, and organics. However, clay soils should not be used in fills within the upper 12 inches of final subgrade for the building pad or exterior flatwork, unless the clay soils are lime-treated as described in the Lime Treatment Alternative section of this report.

Imported fill materials should be compactable, well-graded, granular soils with a Plasticity Index of 15 or less when tested in accordance with ASTM D4318; an Expansion Index of 20 or less when tested in accordance with ASTM D4829, and should not contain particles greater than 1943
Geotechnical Engineering Report Page 18

GREEN ISLAND ROAD LOGISTICS CENTER
WKA No. 12883.01
November 10, 2020
three inches in maximum dimension. In addition, we recommend that the contractor supply a certification for any imported fill materials that designates the fill materials do not contain known contaminants per Department of Toxic Substances Control’s guidelines for clean fill, and have corrosion characteristics within acceptable limits. Imported soils should be approved by the Geotechnical Engineer prior to being transported to the site.

All earthwork operations should be accomplished in accordance with the recommendations contained within this report and the Guide Earthwork Specifications provided in Appendix B.

We recommend the Geotechnical Engineer’s representative be present on a regular basis during all earthwork operations to observe and test the engineered fill and to verify compliance with the recommendations of this report and the project plans and specifications.

Cut and Fill Slopes
We anticipate that cut and fill slopes less than 10 feet in vertical height may be constructed to provide level building areas. In our professional opinion, fill slopes should be inclined no steeper than 2(h):1(v). This slope recommendation is based on our experience with similar conditions since no detailed slope stability analysis was performed to justify steeper slopes.

Given this inclination, however, there is a modest risk that displacement, movement, and/or soil sloughing could occur in the event of strong seismic ground shaking. For the native soils and compacted fill conditions anticipated, we expect this movement to be relatively shallow, requiring limited cleanup and dressing to restore the slopes to their original condition. If this risk is unacceptable to the owner, the slopes should be flattened to 3(h):1(v) or flatter.

Since the proposed detention pond embankments will be immersed below water, the embankments should be constructed at an inclination of 3(h):1(v) or flatter. Like discussed above, some shallow seated displacement or movement should be anticipated in the event of strong seismic ground shaking. If this condition is unacceptable, the embankments should be flattened.

Paved interceptor drains should be provided along the tops of slopes where the tributary area flowing toward the slope has a drainage path greater than 40 feet, measured horizontally. The interceptor drains or terraces should be sloped to a suitable drainage device and disposed offsite well below the toe of the slope. Drop inlets and storm sewers should not be installed near the crests of slopes because leakage can result in maintenance problems or possible slope failure. The slopes should be inspected periodically for erosion, and if detected, repaired immediately. To reduce erosion and gulling, all disturbed areas should be planted with erosionresistant vegetation suited to the area. As an alternative, jute netting or geotextile erosion control mats can be installed per the manufacturer’s recommendations. Slopes should be overbuilt and cutback to design grades and inclinations. 1944
Geotechnical Engineering Report Page 19

GREEN ISLAND ROAD LOGISTICS CENTER
WKA No. 12883.01
November 10, 2020
Utility Trench Backfill
Utility trench backfill within structural areas (e.g. building, exterior flatwork, pavements, etc.) should be mechanically compacted as engineered fill in accordance with the following recommendations. Bedding and initial backfill around and over the pipe should conform to the pipe manufacturer’s recommendations and applicable sections of the governing agency standards.

Based on explorations performed at the site and available groundwater data, we anticipate excavations extending below 10 feet below site grade may encounter groundwater (depending on the time of year) and may require dewatering. Where groundwater is encountered, the use of sumps, submersible pumps, deep wells or a well point system could be used as methods to lower the groundwater level. The dewatering method used will depend on the soil conditions, depth of the excavation and amount of groundwater present within the excavation. Dewatering, if required, should be the contractor’s responsibility. The dewatering system should be designed and constructed by a dewatering contractor with local experience. We recommend the selected dewatering system lower the groundwater level to at least two feet below the bottom of the proposed excavations.

It is likely that materials excavated from trenches will be at elevated moisture contents and will require significant aeration or a period of drying to reach a compactable moisture content. We recommend bid documents contain a unit price for the removal and drying of saturated soils, or replacement with approved import soils.

We recommend that on-site soil be used as trench backfill, especially below the non-expansive or lime-treated material within the footprint of the interior concrete slabs. Utility trench backfill should be placed in maximum eight-inch lifts (compacted thickness), thoroughly moisture conditioned to at least two percent above the optimum moisture content, and mechanically compacted to at least 90 percent relative compaction. Within the upper 12 inches of final subgrade for the interior concrete slabs and exterior flatwork, trench backfill should consist of granular material placed and compacted as described in the Engineered Fill Construction section of this report, unless the lime-treatment alternative is selected. Where the top 12 inches of the interior concrete slabs and exterior flatwork areas consist of lime-treated soils, the upper 12 inches of trench backfill should consist of controlled density fill (CDF) or aggregate base compacted to at least 95 percent relative compaction. Within the upper six inches of untreated pavement subgrade soils and upper 12 inches of lime-treated pavement subgrade soils, compaction should be increased to at least 95 percent relative compaction at no less than two percent above the optimum moisture content.
1945
Geotechnical Engineering Report Page 20

GREEN ISLAND ROAD LOGISTICS CENTER
WKA No. 12883.01
November 10, 2020
We recommend that all underground utility trenches aligned nearly parallel with new foundations be at least three feet from the outer edge of foundations, wherever possible. Trenches should not encroach into the zone extending outward at a one horizontal to one vertical (1H:1V) inclination below the bottom of foundations. Additionally, trenches parallel to existing foundations should not remain open longer than 72 hours. The intent of these recommendations is to prevent loss of both lateral and vertical support of foundations, resulting in possible settlement.

Foundations
The proposed structures may be supported upon continuous and/or isolated spread foundations. Due to expansive soil considerations, the foundations should extend at least 18 inches below lowest adjacent soil grade. Lowest adjacent soil grade is defined as the grade upon which the capillary break material is placed or exterior soil grade, whichever is lower.

Continuous foundations supporting should maintain minimum widths of 15; while isolated spread foundations should be at least 24 inches in plan dimension. Foundations should be continuous around the perimeter of the building to reduce moisture variations beneath the structures. If shrinkage cracks appear in the footing excavations, the excavations should be thoroughly moistened to close all cracks prior to placement of concrete.

Foundations bearing on undisturbed or compacted native soils, engineered fill, or a combination of those materials may be sized for maximum allowable “net” soil bearing pressure of 3,000 pounds per square foot (psf) for dead plus live load. A one-third increase in the allowable bearing pressure may be applied when considering short-term loading due to wind or seismic forces. The weight of the foundation concrete extending below lowest adjacent soil grade may be disregarded in sizing computations.

Total settlement of an individual foundation will vary depending on the plan dimensions of the foundation and the actual load supported. Based on the foundation criteria discussed above and the assumed foundation loads, foundations are anticipated to experience a maximum total static settlement on the order of about ¾ to 1 inch, and differential settlement on the order of about ½ inch for 50 lineal feet or the shortest distance of the structure, whichever is less.

As discussed in the Liquefaction Potential section of the Conclusions, it is estimated that up to 1 inch of differential settlement over a horizontal distance of 100 feet could occur in the event of strong ground shaking (earthquake with a return period of 2,475 years or 2% probability of exceedance in 50 years).
1946
Geotechnical Engineering Report Page 21

GREEN ISLAND ROAD LOGISTICS CENTER
WKA No. 12883.01
November 10, 2020
All foundations be adequately reinforced to provide structural continuity, mitigate cracking and permit spanning of local soil irregularities. The structural engineer should determine final foundation reinforcing requirements.

Resistance to lateral foundation displacement may be computed using an allowable friction factor of 0.30, which may be multiplied by the effective vertical load on each foundation.

Additional lateral resistance may be computed using an allowable passive earth pressure equivalent to a fluid pressure of 300 psf per foot of depth, acting against the vertical projection of the foundation. These two modes of resistance should not be added together unless the frictional component is reduced by 50 percent since full mobilization of the passive resistance requires some horizontal movement, effectively reducing the frictional resistance. We recommend that all foundation excavations be observed by the Geotechnical Engineer’s representative prior to placement of reinforcement and concrete to verify firm bearing materials are exposed.

Interior Floor Slabs
Conventional floor slabs in combination with shallow spread foundations may be used for support of the proposed structures. As discussed in the Soil Expansion Potential section of the Conclusions, the near-surface soil underlying the site and anticipated clay fill can exhibit significant expansion characteristics.

The most direct method to reduce expansive soil risks and improve the subgrade conditions would be to support the proposed floor slabs on a layer of compacted, non-expansive fill. This procedure consists of placing at least 12 inches of non-expansive fill directly below the proposed floor slab system. The non-expansive fill should be moisture conditioned to at or above its optimum moisture content and compacted as engineered fill. Specific requirements for import fill are presented in the Engineered Fill section. The non-expansive soil pads could be prepared by removing and replacing the native clay, raising the building pads above existing site grade, or a combination of both. A capillary break or other slab support system placed directly below the floor slabs should not replace in whole or part the non-expansive fill layer.

The zone of non-expansive soil should extend laterally at least 3 feet outside the perimeter of the structures. Prior to placement of the non-expansive fill, the moisture content of the underlying clay soil should be checked. If the soil moisture content is found to be less than1 percentage point above the optimum moisture content, the soil moisture content should be raised using liberal sprinkling, flooding or another suitable method. A representative of the Geotechnical Engineer should perform a field check of the soil moisture content and relative compaction prior to placement of the non-expansive fill. 1947
Geotechnical Engineering Report Page 22

GREEN ISLAND ROAD LOGISTICS CENTER
WKA No. 12883.01
November 10, 2020
A second approach (lime treatment) consists of mixing the upper 12 inches of subgrade soils within the proposed floor slab area with dolomitic or high calcium quick lime and compacting the soil as engineered fill. The subgrade preparation, spreading, mixing, compacting and lime type should meet the requirements outlined in Section 24 of the Caltrans Standard Specifications.

The zone of lime-treated soil should extend laterally at least 3 feet outside the perimeter of the proposed structure. Based on our previous experience, 4½ pounds of quick lime per cubic foot of soil may be assumed for planning purposes. The lime treated subgrade soils should be compacted to at least 90 percent relative compaction.

At least 2 to 3 days prior to spreading or mixing the lime, the moisture content of the underlying, untreated clay soil should be checked. If the soil moisture content is found to be dry of optimum, the soil moisture content should be raised using liberal sprinkling, flooding or another suitable method. A representative of the Geotechnical Engineer should be on-site during treatment operations to document spreading, mixing and compaction operations and provide supplemental/revised recommendations, if warranted, based on the soil conditions observed.

Following lime treatment, the treated soil should be properly cured by continual sprinkling with water to keep the surface damp, combined with light rolling to keep the surface knitted together.

We suggest that the subgrade soils be covered with Class 2 aggregate base or crushed rock within 2 to 3 days of lime treatment in an effort to reduce drying. Periodic sprinkling is still required to keep the surface damp. As an alternative, the treated soil could be cured as discussed in Section 24 of the Caltrans Standard Specifications.

Lime treatment increases the pH of the soil and may not promote plant growth. Accordingly, the landscape designer should be consulted during pre-construction to verify that future landscaping is suitable for lime treated soils. If the landscaping is not suitable, the lime-treated soils should be completely removed and replaced prior to planting.

The interior concrete slabs should be at least four inches thick, however, the project structural or civil engineer should determine final floor slab thickness, reinforcement and joint spacing.

Temporary loads exerted during construction from vehicle traffic, cranes, forklifts, other construction equipment, rack loads, and storage of palletized construction materials, etc. should be considered in the design of the thickness and reinforcement of the interior concrete slabs-ongrade.

Provided the building pad is constructed in accordance with the recommendations included in this report (12 inches of non-expansive, granular soils or lime-treated clay soils, and six inches of aggregate base where applicable), a soil modulus of reaction (ks) of 200 kips per cubic foot (kcf) or 115 pounds per cubic inch (pci) may be utilized for design of floor slabs subjected to vehicle/fork lift traffic or any other loading conditions described above. 1948
Geotechnical Engineering Report Page 23

GREEN ISLAND ROAD LOGISTICS CENTER
WKA No. 12883.01
November 10, 2020
Moisture Penetration Resistance
It is likely that the subgrade soils below floor slabs will become very moist or wet at some time during the life of the structures. This is a certainty if the subgrade soils are constructed during the wet season or poor drainage conditions exist adjacent to structures. For this reason, it should be assumed that interior floor slabs with moisture-sensitive floor coverings or coatings will require protection against moisture or moisture vapor penetration through the slabs.

Interior floor slabs for the planned buildings should, as a minimum, be underlain by a layer of free-draining crushed rock/gravel, serving as a deterrent to migration of capillary moisture. The crushed rock/gravel layer should be between four- and six-inches-thick and graded such that 100 percent passes a one-inch sieve and less than five percent passes a No. 4 sieve.

Additional moisture protection may be provided by placing a vapor retarder membrane (at least 10-mils thick) directly over the crushed rock/gravel. The water vapor retarder membrane should meet or exceed the minimum specifications as outlined in ASTM E1745 and be installed in strict conformance with the manufacturer’s recommendations. For warehouse portions of the proposed buildings that will not have moisture-sensitive floor coverings or coatings, the vapor retarder membrane should be placed directly over 4 to 6 inches of compacted aggregate base.

Floor slab construction practice over the past 30 years or more has included placement of a thin layer of dry sand or pea gravel over the vapor retarder membrane. The intent of the sand/pea gravel is to aid in the proper curing of the slab concrete. However, during the wet seasons moisture can become trapped in the sand or pea gravel, which can lead to excessive moisture vapor emissions from floor slabs. As a consequence, we consider use of the sand/pea gravel layer as optional. The concrete curing benefits should be weighed against efforts to reduce slab moisture vapor transmission.

It is emphasized that the crushed rock/grave and the vapor retarder membrane suggested above provides only a limited, first line of defense against soil-related moisture issues and will not "moisture proof" the slab. Nor do these measures provide an assurance that slab moisture transmission levels will be within tolerable levels to prevent damage to floor coverings or other building components. If increased protection against moisture vapor penetration is desired, a concrete moisture protection specialist should be consulted. The design team should consider all available measures for slab moisture protection. It is commonly accepted that maintaining the lowest practical water-cement ratio in the slab concrete is one of the most effective ways to reduce future moisture vapor penetration of the completed slabs. 1949
Geotechnical Engineering Report Page 24

GREEN ISLAND ROAD LOGISTICS CENTER
WKA No. 12883.01
November 10, 2020
Retaining Walls
All retaining walls or below grade walls for the buildings should be designed to resist the lateral soil pressures of the retained soils. Retaining walls that are fixed/restrained at the top should be capable of resisting an “at-rest” lateral soil pressure equal to an equivalent fluid pressure of 60 psf per foot of the wall height (fully drained conditions). Retaining walls above the estimated high groundwater level that will be allowed to slightly rotate about their base (unrestrained at the top or sides) should be capable of resisting an "active" lateral soil pressure equal to an equivalent fluid pressure of 40 psf per foot of wall height (fully drained conditions), If structural elements, i.e., foundations, roadways, etc., encroach the one horizontal to one vertical (1H:1V) projection from the bottom of retaining walls, the retaining walls should account for surcharge loads resulting from those structural elements. Additionally, any below-grade retaining walls should also account for surcharge loads resulting from construction equipment, vehicles, palletized materials, etc. that encroach the one horizontal to one vertical (1H:1V) projection from the bottom of the below-grade retaining walls. Surcharge loading under the circumstances described above should be evaluated by the retaining wall designer on a caseby-case basis and be included in their design of the walls. The retaining wall designer should evaluate the surcharge load distribution, magnitude of the surcharge resultant force to be applied on the walls, and the location of where the resultant force should be applied on the walls. Surcharge loading on the retaining walls will depend on the specific surcharge load type (e.g. point load, distributed load, etc.) and distance away from the retaining walls.

Retaining wall or below grade walls should be fully drained to prevent the build-up of hydrostatic pressures behind the wall. Retaining walls should be provided with a drainage blanket of Class 2 permeable material, Caltrans Standard Specification, Section 68-2.02F(3), at least one foot wide extending from the base of wall to within one foot of the top of the wall. The top foot above the drainage layer should consist of compacted on-site or imported engineered fill materials, unless covered by a concrete slab or pavement. Weep holes or perforated rigid pipe, as appropriate, should be provided at the base of the wall to collect accumulated water.

Drainpipes, if used, should slope to discharge at no less than a one percent fall to suitable drainage facilities. Open-graded ½ to ¾ inch crushed rock may be used in lieu of the Class 2 permeable material provided the rock and drain pipe are completely enveloped in an approved non-woven, geotextile filter fabric. Alternatively, approved geotextile drainage composites, such as MiraDRAIN®, may be used in lieu of the drain rock layer. If used, geocomposite drain panels should be installed in accordance with the manufacturer’s recommendations. 1950
Geotechnical Engineering Report Page 25

GREEN ISLAND ROAD LOGISTICS CENTER
WKA No. 12883.01
November 10, 2020
If efflorescence (discoloration of the wall face) or moisture/water penetration of the retaining walls is not acceptable, moisture/water-proofing measures should be applied to the back face of the walls. A moisture/water-proofing specialist should be consulted to determine specific protection measures against moisture/water penetration through the walls.

Structural backfill materials for retaining walls within a one horizontal to one vertical (1H:1V) projection from the bottom of the walls (other than the drainage layer) should consist of imported, granular material or native sand and silt that does not contain significant quantities of rubbish, rubble, organics and rock over four inches in size. Clay, pea gravel and/or crushed rock should not be used for structural wall backfill. Structural wall backfill should be placed, moisture conditioned and compacted in accordance with recommendations provided in the Engineered Fill section of this report.

Foundations for support of retaining or below grade walls should be designed using the appropriate foundation design parameters provided in the Foundations section included in this report.

Exterior Flatwork
The final subgrade for exterior concrete flatwork (i.e., sidewalks, patios, etc.) should be prepared and constructed in accordance with recommendation provided in the Interior Floor Slab section above. The zone of non-expansive fill or lime-treated soils can be reduced to at least 1 foot laterally outside the perimeter of the flatwork.

As an alternative, the subgrade soils could be presoaked by wetting and pre-swelling the subgrade soils prior to placement of concrete, thus reducing the potential for post-construction movement. This approach tends to be the less costly, however, the risk for isolated heaving and cracking is greater since it can be difficult to uniformly moisture condition and completely pre-swell the subgrade soil prior to placement of concrete. Furthermore, pre-soaking also softens and weakens the clay, making this this approach not appropriate where flatwork will support vehicular traffic, heavy concentrated loads, heavy equipment or machinery due to settlement and bearing concerns.

Following subgrade preparation, presoaking consists of wetting or soaking the upper 18 inches of final soil subgrade in order to uniformly raise the soils’ moisture content to a uniform, nearsaturated moisture condition. The zone of wetting should extend laterally at least one foot outside the perimeter of the flatwork. Presoaking is usually performed using liberal sprinkling, flooding, or other suitable method. The time required for pre-soaking could vary from a few days to over a week depending on the condition of the subgrade soils. If the exposed soils are kept moist or wet following subgrade preparation, the amount and time required for presoaking 1951
Geotechnical Engineering Report Page 26

GREEN ISLAND ROAD LOGISTICS CENTER
WKA No. 12883.01
November 10, 2020
is often reduced. Likewise, restricting vehicle or equipment traffic following earthwork will decrease the potential for over-compacting the soils and reducing the ability for water to penetrate. A representative of the Geotechnical Engineer should perform a field check of the soil’s moisture content and consistency within three days of concrete placement. In hot and/or windy weather, the field moisture check should be performed within 24 hours of concrete placement.

The exterior flatwork concrete should be at least four inches thick and underlain by at least four inches of aggregate base compacted to at least 95 percent relative compaction to provide stability during slab construction and to protect the soils from disturbance during construction.

Consideration should be given to thickening the edges of the slabs at least twice the slab thickness where wheel traffic is expected over the slabs. Expansion joints should be provided to allow for minor vertical movement of the flatwork. Exterior flatwork should be constructed independent of other structural elements by the placement of a layer of felt material between the flatwork and the structural element. The slab designer should determine the final thickness, strength and joint spacing of exterior slab-on-grade concrete. The slab designer should also determine if slab reinforcement for crack control is required and determine final slab reinforcing requirements.

Because of seasonal wetting and drying or irrigation of the soil, isolated differential movement and cracking sometimes forms along the outside edges of exterior flatwork. To reduce this risk, consideration should be given placing lateral cutoffs along the outside edges of the flatwork, doweling joints to reduce tripping hazards, and/or stiffening the flatwork by increasing the concrete thickness and including reinforcing steel.

Areas adjacent to new exterior flatwork should be landscaped to maintain more uniform soil moisture conditions adjacent to and beneath flatwork. Final landscaping plans not allow fallow ground adjacent to exterior concrete flatwork.

Practices recommended by the Portland Cement Association (PCA) for proper placement, curing, joint depth and spacing, construction, and placement of concrete should be followed during exterior concrete flatwork construction.

Site Drainage
Final site grading should be accomplished to provide positive drainage of surface water away from the buildings and prevent ponding of water adjacent to foundations, slabs or pavements.

The subgrade adjacent to the buildings should be sloped away from foundations at a minimum two percent gradient for at least 10 feet, where possible. We recommend connecting all roof drains to solid drainage pipes which are connected to available drainage features that convey 1952
Geotechnical Engineering Report Page 27

GREEN ISLAND ROAD LOGISTICS CENTER
WKA No. 12883.01
November 10, 2020
water away from the buildings, or discharging the drains onto paved or hard surfaces that slope away from the foundations. Discharging or ponding of surface water should not be allowed adjacent to the building, exterior flatwork or pavements. Landscape berms, if planned, should not be constructed in such a manner as to promote drainage toward the buildings.

Pavement Design
The subgrade soils in pavement areas should be prepared and constructed in accordance with recommendations provided in the Subgrade Preparation and Engineered Fill sections.

All aggregate base should be compacted to at least 95 relative compaction.

The moisture content of the prepared subgrade soils should be maintained until placement of the aggregate base by periodic sprinkling with water or other suitable method. If there is a delay between placing the aggregate base and asphalt-concrete, the aggregate base should also be periodically sprinkled or wetted to prevent drying of the underlying soil subgrade. A field check of the subgrade soils moisture condition should be performed by the Geotechnical Engineer’s representative prior to placement of the aggregate base.

As an alternative, the upper 12 inches of subgrade soil can be stabilized by mixing it with dolomitic or high calcium quick lime (lime-treatment). The subgrade preparation, spreading, mixing, compacting, lime type and curing should meet the criteria discussed in the Interior Floor Slab section. The zone of lime-treated soil should extend laterally at least two feet outside the perimeter of the proposed pavement subgrade. The lime-treated subgrade soil should be compacted to at least 95 percent relative compaction. A representative of the Geotechnical Engineer should be on-site during treatment operations to document spreading, mixing and compaction operations and provide supplemental/revised recommendations, if warranted, based on the soil conditions observed.

Based on laboratory testing results and previous nearby experience, an R-value of 5 was used for design of pavements supported on compacted native clay and an R-value of 50 was used for lime treated clays. The pavement sections presented in Table 3 have been calculated using traffic indices assumed to be appropriate for the project using pavement design criteria outlined in Chapters 600 to 670 of the California Highway Design Manual (Caltrans, 2019), and Sacramento County, November 1, 2009 Street Design Standards. The project civil engineer should determine the appropriate traffic index and pavement section based on anticipated traffic conditions. If needed, we can provide alternative pavement sections for different traffic indices. 1953
Geotechnical Engineering Report Page 28

GREEN ISLAND ROAD LOGISTICS CENTER
WKA No. 12883.01
November 10, 2020
Table 3: On-site Pavement Design Alternatives
Traffic
Index
(TI) Pavement Use
Untreated Subgrades
R-value = 5
Lime-Treated Subgrades Soils (**)
R-value = 50
Type A
Asphalt
Concrete
(inches)
Class 2
Aggregate
Base
(inches)
Portland
Cement
Concrete
(inches)
Type A
Asphalt
Concrete
(inches)
Class 2
Aggregate
Base
(inches)
Portland
Cement
Concrete
(inches)

4.5 Light Automobile
Parking Only
2½* 10 -- 2½* 4 --
3* 8 -- 3* 4 --
-- 4 6 -- 4 4

6.5 Automobile,
Light 2- to 3-axle
Truck Traffic, Fire
Lanes and Trash
3 16 -- 3* 4 --
4* 14 -- 4* 4 --
-- 6 6 -- 5 4

8.0 Light-Moderate
4-axle-Truck Traffic
3½ 20 -- 3½ 9 --
5* 18 -- 5* 6 --
-- 7 6 -- 6 4
9 Moderate-Heavy
5-axle-Truck Traffic
(AADTT ≈ 75)
4½ 22 -- 4½ 11 --
5½* 21 -- 5½* 9 --
-- 8 8 -- 6½ 4

10.0 Heavy
5-axle-Truck Traffic
(AADTT ≈ 170)
5 25 -- 5 13 --
6½* 23 -- 6½* 11 --
-- 8 10 -- 7½ 6
* = Asphalt concrete thickness contains the Caltrans safety factor. **= Lime-treated subgrade should be at least 12 inches thick and possess a minimum R-value of 40 when testing in accordance with California Test 301.

AADTT = Annual Average Daily Truck Traffic, assuming 5-axles trucks and 20-year ESAL Constant.

In the summer heat, high axle loads coupled with shear stresses induced by sharply turning tire movements can lead to failure in asphalt concrete pavements. Therefore, we recommend that consideration be given to using Portland concrete cement (PCC) pavements in areas subjected to concentrated heavy wheel loading, such as entry driveways and in front of trash enclosures.

Alternate PCC pavement sections have been provided above in Table 3. All aggregate base should be compacted to at least 95 percent relative compaction. 1954
Geotechnical Engineering Report Page 29

GREEN ISLAND ROAD LOGISTICS CENTER
WKA No. 12883.01
November 10, 2020
We suggest the concrete slabs be constructed with thickened edges in accordance with American Concrete Institute (ACI) design standards, latest edition. Reinforcing for crack control, should be provided in accordance with ACI guidelines. Reinforcement must be located at mid-slab depth to be effective. Joint spacing and details should conform to the current PCA or ACI guidelines. Per the California Highway Design manual, PCC should achieve a minimum modulus of rupture/flexural strength of 625 pounds per square inch (psi) at 28 days. Per PCA guidelines, a minimum compressive strength of 4,000 psi at 28 days is required to achieve the specified modulus of rupture.

All pavement materials and construction methods of structural pavement sections should conform to the applicable provisions of the Caltrans Standard Specifications and Napa County Standards, latest editions.

Efficient drainage of all surface water to avoid infiltration and saturation of the supporting aggregate base and subgrade soils is important to pavement performance. Weep holes could be provided at drainage inlets, located at the subgrade-aggregate base interface, to allow accumulated water to drain from beneath the pavements.

Consideration should be given to using full-depth curbs between landscaped areas and pavements to serve as a cut-off for water that could migrate into the pavement base materials or subgrade soils.

Ancillary Foundations
Foundations for lightly-loaded, ancillary structures not structurally connected to the proposed buildings, such as sound walls, landscape walls, monuments, trash enclosures, or similar structures, may be supported upon conventional spread foundations or drilled, cast-in-place reinforced concrete piers (drilled piers). Drilled piers may be used for support of light poles or similar structures.

Conventional Spread Foundations
Conventional spread foundations should bear on firm, undisturbed ground, engineered fill, or a combination of these materials, as confirmed by the Geotechnical Engineer or his representative. The spread foundations should be at least 12 inches wide and extend at least 18 inches below the lowest adjacent soil grade. The foundations may be sized using a maximum allowable soil bearing pressure of 2,000 psf, with a one-third increase for wind or seismic forces. Lateral foundation resistance may be determined using the factors presented in the Foundations section. The upper 12 inches of subgrade soil should be disregarded when estimating lateral resistance.
1955
Geotechnical Engineering Report Page 30

GREEN ISLAND ROAD LOGISTICS CENTER
WKA No. 12883.01
November 10, 2020
Drilled, Cast-in-Place Concrete Piers
Drilled piers should be at least 18 inches in diameter, extend at least five feet below lowest adjacent soil grade, and sized using a maximum allowable end-bearing capacity of 4,000 psf or an allowable skin friction of 250 psf for dead plus live loads, which may be applied over the surface area of the pier. These values may be increased by one-third to include short-term wind or seismic forces. The weight of foundation concrete below grade may be disregarded in sizing computations.

Uplift resistance of drilled pier foundations may be computed using the following resisting forces, where applicable: 1) weight of the pier concrete and, 2) the allowable skin friction of 250 psf applied over the shaft area of the drilled pier. Increased uplift resistance can be achieved by increasing the diameter of the drilled pier or increasing the depth.

The upper 12 inches of skin friction should be neglected for axial capacity or uplift resistance unless the drilled pier is surrounded by slab concrete or pavements for a distance of at least three feet from the edge of the foundation.

Sizing of drilled piers to resist lateral loads can be evaluated using Section 1807.1 of the 2016 CBC. An allowable lateral soil bearing pressure of 200 psf per foot of depth may be used for the CBC parameters S1 (equation 18-1) and S3 (equations 18-2 and 18-3). If a deflection of ½ inch at the ground surface is acceptable, this value may be doubled. The upper 12 inches of the subgrade should be neglected when determining lateral resistance.

Reinforcement and concrete should be placed in the pier excavations as soon as possible after excavation is completed to reduce the potential for caving. In no case should the elapsed time between completion of the pier excavation and the start of concrete placement exceed 48 hours. If the piers are designed using the allowable vertical bearing pressure, the bottom of the pier excavations should be free of loose or disturbed soils prior to placement of the concrete.

Cleaning of the bearing surface should be verified by the Geotechnical Engineer prior to concrete placement.

If drilled piers are designed using end-bearing capacity and seepage or groundwater is encountered, the water should be pumped from the pier excavation to allow inspection and concrete placement. Otherwise, the concrete should be placed using tremie methods from the bottom of the hole, while keeping the tremie pipe below the surface of the concrete at all times. 1956
Geotechnical Engineering Report Page 31

GREEN ISLAND ROAD LOGISTICS CENTER
WKA No. 12883.01
November 10, 2020
Site Drainage
Because of expansive soil concerns, the performance of foundations and concrete slabs relies on how well storm runoff and irrigation water drains from the site. Final site grading should be accomplished to provide positive drainage of surface water away from the buildings and prevent ponding of water adjacent to foundations, slabs or pavements. The subgrade adjacent to the buildings should be sloped away from the building at a minimum two percent gradient for at least five feet, where possible. All roof drains should be connected to non-perforated rigid pipes, which in-turn are connected to available drainage features that convey water away from the buildings or discharging the drainage onto paved or hard surfaces that slope away from the buildings. Landscape berms, if planned, should not be constructed in such a manner as to promote drainage toward the buildings.

Drought Considerations
The State of California can experience extended periods of severe drought conditions.

Desiccated clay can shrink and crack and the ability for landowners to use irrigation as a means for maintaining landscape vegetation and soil moisture can be inhibited for unpredictable periods of time. For this reason, landscape and hardscape systems for this development should be carefully planned to prevent the desiccation of soils under and near foundations and slabs.

Trees with invasive shallow root systems should be avoided. No trees or large shrubs that could remove soil moisture during dry periods should be planted within five feet of any foundation or slab. Fallow ground adjacent to foundations must be avoided.

To reduce potential for soil creep adversely affecting foundations or exterior flatwork, we recommend a minimum horizontal distance of five feet be provided and maintained between the outside edge of the foundation or flatwork to the nearest adjacent slope (e.g. building pad hinge point), for slopes greater than two feet in height.

Geotechnical Engineering Observation and Testing During Earthwork Construction Site preparation should be accomplished in accordance with the recommendations of this report and the Guide Earthwork Specifications provided in Appendix D. Geotechnical testing and observation during construction is considered a continuation of our geotechnical engineering investigation. Wallace-Kuhl & Associates should be retained to provide testing and observation services during site clearing, preparation, earthwork, and foundation construction at the project to verify compliance with this geotechnical report and the project plans and specifications, and to provide consultation as required during construction. These services are beyond the scope of work authorized for this investigation; however, we would be pleased to submit a proposal to provide these services upon request.
1957
Geotechnical Engineering Report Page 32

GREEN ISLAND ROAD LOGISTICS CENTER
WKA No. 12883.01
November 10, 2020
Section 1803.5.8 “Compacted Fill Material” of the 2016 CBC requires that the geotechnical engineering report provide a number and frequency of field compaction tests to determine compliance with the recommended minimum compaction. Many factors can affect the number of tests that should be performed during construction, such as soil type, soil moisture, season of the year and contractor operations/performance. Therefore, it is crucial that the actual number and frequency of testing be determined by the Geotechnical Engineer during construction based on their observations, site conditions, and difficulties encountered. As a preliminary guideline, we recommend the following minimum tests:
• mass grading: one test per 500 cubic yards of compacted fill or one per day of work, whichever is greater
• final subgrade preparation: one test per 5,000 square feet • aggregate base compaction: one test per 5,000 square feet • utility backfill: one test per foot of backfill for every 150 linear feet of trench • wall backfill: one test per foot of backfill for every 100 linear feet of wall In the event that Wallace-Kuhl & Associates is not retained to provide geotechnical engineering observation and testing services during construction, the Geotechnical Engineer retained to provide these services should indicate in writing that they agree with the recommendations of this report, or prepare supplemental recommendations as necessary. A final report by the “Geotechnical Engineer” should be prepared upon completion of the project.

Additional Services
We recommend that our firm be retained to review the final plans and specifications to determine if the intent of our recommendations has been implemented in those documents. We would be pleased to submit a proposal to provide these services upon request.

LIMITATIONS
Our recommendations are based upon the information provided regarding the proposed project, combined with our analysis of site conditions revealed by the field exploration and laboratory testing programs. We have used prudent engineering judgment based upon the information provided and the data generated from our study. This report has been prepared in substantial compliance with generally accepted geotechnical engineering practices that exist in the area of the project at the time the report was prepared. No warranty, either express or implied, is provided.
1958
Geotechnical Engineering Report Page 33

GREEN ISLAND ROAD LOGISTICS CENTER
WKA No. 12883.01
November 10, 2020
If the proposed construction is modified or relocated or, if it is found during construction that subsurface conditions differ from those we encountered at our exploration locations, we should be afforded the opportunity to review the new information or changed conditions to determine if our conclusions and recommendations must be modified.

We emphasize that this report is applicable only to the proposed construction and the investigated site. This report should not be utilized for construction on any other site. This report is considered valid for the proposed construction for a period of two years following the date of this report. If construction has not started within two years, we must re-evaluate the recommendations of this report and update the report, if necessary.

Wallace - Kuhl & Associates
Joseph Ybarra Gary H. Gulseth
Staff Geologist Senior Engineer
1959
1960
1961
PP=3.0
PP=2.25
Dark gray, moist, stiff, sandy LEAN CLAY (CL)
Yellowish brown, moist, medium dense, clayey SAND with gravel (SC) Reddish brown, moist, very stiff, sandy LEAN CLAY (CL)
Boring was terminated at approximately 10.0 feet below existing ground surface.

D1-1I
D1-2I
D1-3I
16 26
19 91
85 105

16.2 17.3

21.9 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 3

10.0 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
KRL
CME 55 HT
V&W Drilling

SAMPLE DATA

ENGINEERING CLASSIFICATION AND DESCRIPTION
Date(s)
Drilled
6 ELEVATION, feetSAMPLE
Checked
By
Logged
By JRY
Drilling
Contractor
Groundwater Depth
[Elevation], feet
Diameter(s)
of Hole, inches
MOISTURECONTENT, %

TEST DATA

2.0" Modified California with 6-inch
sleeve
9/21/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D1
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:32 PM 1962
PP>4.5
PP=3.5
PP=3.75
PP=4.5
Dark gray, moist, hard, silty LEAN CLAY (CL)
brown, with sand, very stiff, iron oxide staining
Reddish brown, moist, medium dense, clayey fine to medium SAND (SC) Reddish brown, moist, hard, LEAN CLAY (CL)
Boring was terminated at approximately 16.5 feet below existing ground surface.

Groundwater was not encountered.

D2-1I
D2-2I
D2-3I
D2-4I
28 34
22 27
99 102
107

17.4 18.3

19.8 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 4

16.5 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
KRL
CME 55 HT
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
9/21/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D2
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
15 BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:32 PM 1963
PP>4.5
PP>4.5
PI
PP>4.5
PP=3.25
PI
PP>4.5
PP=2.25
Dark brown, moist, hard, silty LEAN CLAY (CL)
Dark brown, moist, hard, sandy LEAN CLAY (CL); iron oxide staining yellowish brown
Yellowish brown, moist, very stiff, sandy LEAN CLAY (CL) Reddish brown
Olive to reddish brown, hard
Olive to yellowish brown, very stiff
D3-1
D3-2
D3-3
D3-4
D3-5
D3-6
7 14
20 21
19 23

22.9 16.5

18.8 17.6
Sheet 1 of 2
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 5

51.5 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Hollow Stem Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
KRL
CME 55 HT
V&W Drilling

SAMPLE DATA

ENGINEERING CLASSIFICATION AND DESCRIPTION
Date(s)
Drilled
7 ELEVATION, feetSAMPLE
Checked
By
Logged
By
Bulk @ 0-4', EI, PI
JRY
Drilling
Contractor
Groundwater Depth
[Elevation], feet
Diameter(s)
of Hole, inches
MOISTURECONTENT, %

TEST DATA

1.4" Standard Penetration Test
(SPT)
9/21/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D3
DEPTH, feet
Remarks

20.0 Neat Cement SAMPLE NUMBER NUMBER OF BLOWS
5 10
15 20
25 BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:33 PM 1964
PP=4.0
PP=4.25
PI
PP=3.5
PP=3.0
PP>4.5
hard
Olive brown, wet, medium dense, clayey fine to medium SAND (SC) Olive brown, wet, very stiff, LEAN CLAY with sand (CL)
Brown, wet, very stiff, sandy LEAN CLAY (CL)
At 46.0 feet, a 3" gravel lense
Boring was terminated at approximately 51.5 feet below existing ground surface.

Groundwater was encountered at approximately 20.0 feet below existing ground surface.

D3-7
D3-8
D3-9
D3-10
D3-11
21 18
15 33
23 17.4
ELEVATION, feetDEPTH, feetSAMPLESAMPLENUMBER
LOG OF SOIL BORING D3

TEST DATA

ENGINEERING CLASSIFICATION AND DESCRIPTION

SAMPLE DATA
GRAPHIC LOGNUMBEROF BLOWSMOISTURECONTENT, %DRY UNITWEIGHT, pcfADDITIONALTESTS Sheet 2 of 2
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 5
35 40
45 50
BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:33 PM 1965
PP>4.5
PP>4.5
PP=1.5
Dark brown, moist, hard, silty LEAN CLAY (CL)
Dark brown, moist, hard, sand LEAN CLAY (CL)
reddish brown, very moist, medium stiff, iron oxide staining Olive brown, very moist, medium dense, clayey fine to medium SAND with gravel (SC); with iron oxide staining
Boring was terminated at approximately 16.5 feet below existing ground surface.

Groundwater was not encountered.

D4-1I
D4-2I
D4-3I
D4-4I
20 23
16 28
105
103
105

16.1 15.4

21.7 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 6

16.5 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
KRL
CME 55 HT
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
9/21/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D4
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
15 BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:33 PM 1966
UCC=

4.2 tsf
Dark brown, moist, sandy LEAN CLAY (CL)
yellowish brown, hard
Reddish brown, moist, medium dense, clayey fine to medium SAND (SC) Boring was terminated at approximately 10.0 feet below existing ground surface.

Groundwater was not encountered.

D5-1I
D5-2I
D5-3I
11 31
27 108
111

17.4 14.2

19.5 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 7

10.0 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
KRL
CME 55 HT
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
9/21/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D5
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:33 PM 1967
PP=4.5
Dark gray, moist, hard, silty LEAN CLAY (CL)
Reddish brown, moist, medium dense, gravelly SAND with clay (SP) Brown, very moist, loose, clayey fine to medium SAND (SC) Boring was terminated at approximately 16.5 feet below existing ground surface.

Groundwater was encountered at approximately 15.0 feet below existing ground surface.

D6 @ 0-5'
D6-1I
D6-2I
D6-3I
D6-4I
21 20
10 36
107
103
101

19.4 18.1

21.5 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 8

16.5 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
KRL
CME 55 HT
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
9/21/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D6
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
15 BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:33 PM 1968
PP=3.25
Dark grey, moist, sandy LEAN CLAY (CL)
reddish brown
Reddish brown, moist, medium dense, clayey fine to coarse SAND with gravel (SC) olive to yellowish brown, very moist, increased fines content Boring was terminated at approximately 10.0 feet below existing ground surface.

Groundwater was not encountered.

D7-1I
D7-2I
D7-3I
12 26
22 99
110
109

17.4 17.0

18.7 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 9

10.0 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
KRL
CME 55 HT
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
9/21/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D7
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:33 PM 1969
PP>4.5
PP>4.5
PP=4.5
Dark brown, moist, hard, LEAN CLAY with sand (CL)
Yellowish brown, moist, very dense, clayey fine SAND (SC) Boring was terminated at approximately 10.0 feet below existing ground surface.

Groundwater was not encountered.

D8-1I
D8-2I
D8-3I
13 19
50 98
112
113

19.9 15.9

13.4 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 10

10.0 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
KRL
CME 55 HT
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
9/21/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D8
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:33 PM 1970
PP>4.5
PP=3.25
PP>4.5
Brown, moist, hard, silty LEAN CLAY (CL); with iron oxide staining very stiff
Brown, moist, medium dense, clayey fine to medium SAND (SC) Yellowish brown, moist, hard, sandy LEAN CLAY (CL)
Brown, moist, medium dense, clayey fine to medium SAND with gravel (SC) Boring was terminated at approximately 16.5 feet below existing ground surface.

Groundwater was not encounterd.

D9-1I
D9-2I
D9-3I
D9-4I
22 31
39 27
111
112
113

13.5 15.3

17.2 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 11

16.5 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
KRL
CME 55 HT
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
9/21/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D9
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
15 BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:33 PM 1971
PP>4.5
PP=2.25
Dark brown, moist, hard, silty LEAN CLAY (CL)
very stiff, with fine sand
Yellowish brown, moist, medium dense, clayey fine to medium SAND (SM) increased clay content, slight calcification
Boring was terminated at approximately 10.0 feet below existing ground surface.

Groundwater was not encountered.

D10-1I
D10 @ 0-5'
D10-2I
D10-3I
8 19
42 89
111
112

20.6 13.8

15.6 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 12

10.0 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
KRL
CME 75
V&W Drilling

SAMPLE DATA

ENGINEERING CLASSIFICATION AND DESCRIPTION
Date(s)
Drilled
6 ELEVATION, feetSAMPLE
Checked
By
Logged
By
Bulk @ 0-4'
JRY
Drilling
Contractor
Groundwater Depth
[Elevation], feet
Diameter(s)
of Hole, inches
MOISTURECONTENT, %

TEST DATA

2.0" Modified California with 6-inch
sleeve
9/28/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D10
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:32 PM 1972
PP=2.25
PP=3.25
PP=1.0
Brown, moist, very stiff, LEAN CLAY with sand (CL)
Yellowish brown, medium dense, clayey fine to medium SAND (SC) Yellowish brown, moist, very stiff, LEAN CLAY with sand (CL) medium stiff
Yellowish brown, moist, medium dense, clayey fine SAND (SC) Boring was terminated at approximately 16.5 feet below existing ground surface.

Groundwater was not encountered.

D11-1I
D11-2I
D11-3I
D11-4I
18 30
20 16
105
100
105

17.2 21.3

20.0 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 13

16.5 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
KRL
CME 75
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
9/28/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D11
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
15 BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:32 PM 1973
PP=2.5
PP=3.5
HC
PP=4.0
Brown, moist, very stiff, LEAN CLAY (CL); trace sand
dark reddish brown, increased sand content
dark yellowish brown
Boring was terminated at approximately 10.0 feet below existing ground surface.

Groundwater was not encountered.

D12-1I
D12-2I
D12-3I
11 22
24 114
109

16.9 18.2
Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 14

10.0 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
KRL
CME 75
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
9/28/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D12
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:32 PM 1974
UCC=

5.7 tsf
UCC=

3.7 tsf
PP>4.5
PP=2.5
Yellowish brown, moist, hard, silty LEAN CLAY (CL)
trace sand
very stiff
Boring was terminated at approximately 16.5 feet below existing ground surface.

Groundwater was not encountered.

D13-1I
D13-2I
D13-3I
D13-4I
10 16
24 20
98 106
108

19.1 16.5

18.5 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 15

16.5 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
KRL
CME 55 HT
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
9/22/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D13
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
15 BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:32 PM 1975
PP>4.5
PP=2.75
Dark brown, moist, hard, silty LEAN CLAY (CL)
yellowish brown, very stiff
Dark yellowish brown, very moist, medium dense, clayey fine to coarse SAND (SC) Boring was terminated at approximately 10.0 feet below existing ground surface.

Groundwater was not encountered.

D14-1I
D14-2I
D14-3I
13 19
30 98
97 114

17.8 23.6

16.3 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 16

10.0 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
KRL
CME 55 HT
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
9/22/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D14
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:32 PM 1976
PP=2.0
PP=4.5
PP=4.0
PP>4.5
Dark reddish brown, moist, very stiff, sandy LEAN CLAY (CL) hard
Dark reddish brown, moist, medium dense, clayey fine to medium SAND (SC) Yellowish brown, moist, hard, sandy LEAN CLAY (CL)
slight calcification
Boring was terminated at approximately 16.5 feet below existing ground surface.

Groundwater was not encountered.

D15 @ 0-5'
D15-1I
D15-2I
D15-3I
D15-4I
17 40
25 40
96 111
110

15.9 14.5

16.9 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 17

16.5 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
KRL
CME 75
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
9/28/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D15
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
15 BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:32 PM 1977
PP>4.5
PP=4.25
Light yellowish brown, moist, sandy LEAN CLAY (CL)
Brown, moist, hard, LEAN CLAY (CL)
Yellowish brown, moist, hard, sandy LEAN CLAY (CL)
Boring was terminated at approximately 10.0 feet below existing ground surface.

Groundwater was not encountered.

D16-1I
D16-2I
D16-3I
14 26
25 94
108
110

7.2 17.0

16.8 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 18

10.0 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
KRL
CME 75
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
9/28/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D16
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:32 PM 1978
PP>4.5
PP=3.75
PP=3.5
Dark brown, moist, hard, silty LEAN CLAY (CL)
Reddish brown, moist, very stiff, sandy LEAN CLAY (CL)
Brown, damp, medium dense, clayey fine SAND (SC)
Reddish brown to olive, wet, very stiff, LEAN CLAY (CL) Boring was terminated at approximately 16.5 feet below existing ground surface.

Groundwater was encountered at approximately 12.0 feet below existing ground surface.

D17 @ 0-5'
D17-1I
D17-2I
D17-3I
D17-4I
22 26
17 24
112
110
99 17.3

17.7 20.4
Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 19

16.5 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
KRL
CME 75
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
9/28/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D17
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
15 BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:32 PM 1979
PP=3.0
PP>4.5
Brown, dry, sandy LEAN CLAY (CL)
yellowish brown, moist, very stiff
hard
Boring was terminated at approximately 10.0 feet below existing ground surface.

Groundwater was not encountered.

D18-1I
D18-2I
D18-3I
7 19
23 100
99 120

8.7 22.4

15.9 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 20

10.0 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
KRL
CME 55 HT
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
9/22/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D18
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:32 PM 1980
PP=3.0
PP=2.75
PP>4.5
Dark yellowish brown, moist, very dense, LEAN CLAY with sand (CL) Dark yellowish brown, moist, very dense, sandy LEAN CLAY (CL) At 10.0 feet, a 1" fine to medium sand lense
Light yellowish brown to olive brown, moist, clayey fine to coarse SAND (SC) Boring was terminated at approximately 16.5 feet below existing ground surface.

Groundwater was not encountered.

D19 @ 0-5'
D19-1I
D19-2I
D19-3I
D19-4I
7 21
18 37
107
110
108

22.8 18.0

18.3 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 21

16.5 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
KRL
CME 55 HT
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
9/22/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D19
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
15 BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:32 PM 1981
PP>4.5
PP=3.75
Brown, moist, hard, silty LEAN CLAY (CL)
Yellowish brown, moist, very stiff, sandy LEAN CLAY (CL) Yellowish brown, damp, medium dense, clayey fine to medium SAND (SC) Boring was terminated at approximately 10.0 feet below existing ground surface.

Groundwater was not encountered.

D20-1I
D20-2I
D20-3I
8 17
23 104
111
112

22.3 15.5

17.4 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 22

10.0 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
KRL
CME 55 HT
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
9/22/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D20
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:32 PM 1982
PI
PP=2.0
PP=3.5
PP=3.5
PI
PP=1.0
Brown, moist, stiff, sandy LEAN CLAY (CL)
increased moisture content, very stiff, black staining
Brown, moist, medium dense, clayey fine to medium SAND (SC) Brown, moist, very stiff, sandy LEAN CLAY (CL)
medium stiff
At 26 feet, a 2" fine to medium sand lense
D21-1I
D21-2I
D21-3
D21-4
D21-5
D21-6I
D21-7I
D21-8I
6 17
9 8
18 13
11 10

17.0 20.0

19.5 Sheet 1 of 2
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 23

51.5 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Hollow Stem Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
KRL
CME 55 HT
V&W Drilling

SAMPLE DATA

TEST DATA

1.4" Standard Penetration Test
(SPT)
9/22/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D21
DEPTH, feet
Remarks

20.0 Neat Cement SAMPLE NUMBER NUMBER OF BLOWS
5 10
15 20
25 BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:32 PM 1983
Light reddish brown
increased moistue content
Light reddish brown, wet, medium dense, silty fine to medium SAND (SM) Brown, wet, medium dense, gravelly fine to coarse SAND (SP) Yellowish brown, very moist, dense, clayey fine SAND (SC) Brown, wet, dense, silty fine to medium SAND (SM)
Boring was terminated at approximately 51.5 feet below existing ground surface.

Groundwater was encountered at approximately 15.0 feet below existing ground surface.

D21-9I
D21-10I
D21-11I
D21-12I
D21-13I
11 17
17 36
41 ELEVATION, feetDEPTH, feetSAMPLESAMPLENUMBER
LOG OF SOIL BORING D21

TEST DATA

ENGINEERING CLASSIFICATION AND DESCRIPTION

SAMPLE DATA
GRAPHIC LOGNUMBEROF BLOWSMOISTURECONTENT, %DRY UNITWEIGHT, pcfADDITIONALTESTS Sheet 2 of 2
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 23
35 40
45 50
BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:32 PM 1984
PP=4.5
PP>4.5
PP=3.5
Dark reddish brown, moist, hard, silty LEAN CLAY (CL)
Dark yellowish brown, moist, hard, sandy LEAN CLAY (CL) Dark yellowish brown, moist, medium dense, clayey fine to medium SAND (SC) Reddish brown, moist, very stiff, LEAN CLAY (CL); iron oxide staining Boring was terminated at approximately 16.5 feet below existing ground surface.

Groundwater was not encountered.

D22 @ 0-5'
D22-1I
D22-2I
D22-3I
D22-4I
13 25
22 16
101
107
114

19.6 17.7

15.3 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 24

16.5 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
KRL
CME 55 HT
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
9/22/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D22
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
15 BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:32 PM 1985
UCC=

3.9 tsf
UCC=

3.1 tsf
PP=1.25
Brown, moist, hard, silty LEAN CLAY (CL)
yellowish brown
Yellowish brown, moist, medium dense, clayey fine to medium SAND (SC) Boring was terminated at approximately 10.0 feet below existing ground surface.

Groundwater was not encountered.

D23-1I
D23-2I
D23-3I
9 16
14 89
112
117

24.6 14.7

16.4 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 25

10.0 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
KRL
CME 55 HT
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
9/22/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D23
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:32 PM 1986
PP>4.5
PP=3.75
PP=2.0
Dark reddish brown, moist, hard, silty LEAN CLAY (CL)
very stiff
Boring was terminated at approximately 10.0 feet below existing ground surface.

Groundwater was not encountered.

D24-1I
D24-2I
D24-3I
8 23
18 87
108
104

19.2 18.0

20.3 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 26

10.0 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
KRL
CME 75
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
9/29/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D24
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:32 PM 1987
Dark brown, moist, stiff, silty LEAN CLAY (CL)
light brown, very stiff
with black mottling, sand
Boring was terminated at approximately 10.0 feet below exisiting ground surface.

Groundwater was not encountered.

D25-1I
D25-2I
D25-3I
10 19
21 90
98 106

8.9 24.0

18.8 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 27

10.0 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
JRY
CME 75
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
10/2/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D25
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:32 PM 1988
PI
PP>4.5
PP>4.5
PP=3.0
Dark reddish brown, hard, silty LEAN CLAY (CL)
brown
yellowish brown, very stiff
Dark yellowish brown, wet, medium dense, clayey fine SAND (SC) Boring was terminated at approximately 16.5 feet below existing ground surface.

Groundwater was encountered at approximately 15.0 feet below existing ground surface.

D26 @ 0-4'
D26-1I
D26-2I
D26-3I
D26-4I
17 35
16 28
107
106
105

17.3 19.1

19.9 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 28

16.5 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
KRL
CME 75
V&W Drilling

SAMPLE DATA

ENGINEERING CLASSIFICATION AND DESCRIPTION
Date(s)
Drilled
6 ELEVATION, feetSAMPLE
Checked
By
Logged
By
Bulk @ 0-4', EI
JRY
Drilling
Contractor
Groundwater Depth
[Elevation], feet
Diameter(s)
of Hole, inches
MOISTURECONTENT, %

TEST DATA

2.0" Modified California with 6-inch
sleeve
9/29/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D26
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
15 BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:32 PM 1989
PP>4.5
UCC=

2.7 tsf
PP=4.0
Brown, moist, hard, sandy LEAN CLAY (CL)
Brown, moist, hard, silty LEAN CLAY (CL)
with sand, iron oxide staining
Boring was terminated at approximately 10.0 feet below existing ground surface.

Groundwater was not encountered.

D27-1I
D27-2I
D27-3I
12 20
29 93
102
114

8.6 19.4

15.3 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 29

10.0 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
KRL
CME 75
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
9/29/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D27
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:32 PM 1990
PP>4.5
PP>4.5
PP=2.0
PP=2.5
Reddish brown, moist, hard, silty LEAN CLAY (CL)
brown
wet, with sand
Dark yellowish brown, wet, medium dense, clayey fine to medium SAND (SC) Dark yellowish brown, very moist, very stiff, LEAN CLAY (CL) Boring was terminated at approximately 16.5 feet below exsiting ground surface.

Groundwater was encountered at approximately 13.0 feet below existing ground surface.

D28-1I
D28-2I
D28-3I
D28-4I
12 26
19 18
98 107
105

23.1 15.9

19.4 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 30

16.5 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
KRL
CME 75
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
9/29/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D28
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
15 BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:32 PM 1991
PP=4.5
PP=3.25
Brown, moist, hard, silty LEAN CLAY (CL)
very stiff
Boring was terminated at approximately 10.0 feet below existing ground surface.

Groundwater was not encountered.

D29-1I
D29 @ 0-5'
D29-2I
D29-3I
9 12
17 93
98 22.6

20.9 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 31

10.0 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
KRL
CME 75
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
9/29/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D29
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:32 PM 1992
PP=3.0
PP=3.5
PP=3.25
Brown, moist, very stiff, silty LEAN CLAY (CL)
Reddish brown, moist, very stiff, sandy LEAN CLAY (CL)
Boring was terminated at approximately 16.5 feet below existing ground surface.

Groundwater was not encountered.

D30-1I
D30-2I
D30-3I
D30-4I
12 23
20 7
98 94
96 25.7

25.1 24.1
Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 32

16.5 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
KRL
CME 75
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
9/29/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D30
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
15 BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:33 PM 1993
PP=2.25
PP=1.25
Grayish brown, moist, silty LEAN CLAY (CL)
brown
yellowish brown, medium stiff
Yellowish brown, moist, medium dense, clayey fine to medium SAND (SC) Boring was terminated at approximately 10.0 feet below existing ground surface.

Groundwater was not encountered.

D31-1I
D31-2I
D31-3I
13 15
21 84
103
114

5.3 17.5

15.1 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 33

10.0 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
KRL
CME 75
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
9/29/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D31
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:33 PM 1994
PP>4.5
PP=2.75
PI
PP=2.25
PP=1.0
PI
PP=1.5
Brown, moist, hard, silty LEAN CLAY (CL)
Brown, moist, very stiff, sandy LEAN CLAY (CL)
yellowish brown, increased sand content
olive brown, medium stiff, iron oxide staining
wet
very moist
D32-1
D32-2
D32-3
D32-4
D32-5
D32-6
12 17
13 8
10 11
10321.8

23.5 24.2

28.7 Sheet 1 of 2
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 34

51.5 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Hollow Stem Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
KRL
CME 75
V&W Drilling

SAMPLE DATA

ENGINEERING CLASSIFICATION AND DESCRIPTION
Date(s)
Drilled
8 ELEVATION, feetSAMPLE
Checked
By
Logged
By
Bulk @ 0-4'
JRY
Drilling
Contractor
Groundwater Depth
[Elevation], feet
Diameter(s)
of Hole, inches
MOISTURECONTENT, %

TEST DATA

2.0" Modified California with 6-inch
sleeve & 1.4" Standard Penetration
Test (SPT)
9/29/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D32
DEPTH, feet
Remarks

15.0 Neat Cement SAMPLE NUMBER NUMBER OF BLOWS
5 10
15 20
25 BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:33 PM 1995
PP=2.0
PI
Dark yellowish brown, very moist, medium dense, clayey fine SAND with gravel (SC) Dark reddish brown, wet, very stiff, sandy LEAN CLAY (CL) Reddish brown, wet, medium dense, clayey fine SAND (SC); slight calcification Gray, wet, medium dense, fine to coarse SAND with fine gravel (SP) Boring was terminated at approximately 51.5 feet below existing ground surface.

Groundwater was encountered at approxmately 15.0 feet.

D32-7
D32-8
D32-9
D32-10
D32-11
14 20
29 38
36 28.5
ELEVATION, feetDEPTH, feetSAMPLESAMPLENUMBER
LOG OF SOIL BORING D32

TEST DATA

ENGINEERING CLASSIFICATION AND DESCRIPTION

SAMPLE DATA
GRAPHIC LOGNUMBEROF BLOWSMOISTURECONTENT, %DRY UNITWEIGHT, pcfADDITIONALTESTS Sheet 2 of 2
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 34
35 40
45 50
BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:33 PM 1996
PP=1.75
PP>4.5
PP=3.0
PP=0.5
PP=3.5
Brown, moist, medium stiff, sandy LEAN CLAY (CL)
Reddish brown, very moist, silty fine to medium SAND (SM) Brown, moist, hard, sandy LEAN CLAY (CL)
yellowish brown, very stiff
soft
very stiff
Boring was terminated at approximately 16.5 feet below existing ground surface.

Groundwater was not encountered.

D33-1I
D33-2I
D33-3I
D33-4II
D33-4I
17 22
20 16
106
107
96 18.5

15.7 23.4
Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 35

16.5 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
KRL
CME 75
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
9/28/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D33
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
15 BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:33 PM 1997
UCC=

1.8 tsf
UCC=

1.2 tsf
PP=3.75
Brown moist, very stiff, LEAN CLAY with sand (CL)
Light gray, very moist, medium dense, silty fine SAND (SM) Reddish brown, moist, very stiff, sandy LEAN CLAY (CL)
Boring was terminated at approximately 10.0 feet below existing ground surface.

Groundwater was not encountered.

D34-1I
D34-2I
D34-3I
10 20
25 102
107
106

20.2 17.8

17.7 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 36

10.0 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
KRL
CME 75
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
9/28/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D34
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:33 PM 1998
PP=1.5
PP=1.75
PP=1.25
PP=1.25
Olive brown, moist, medium stiff, LEAN CLAY with sand (CL); slight calcification Reddish brown, moist, loose, silty fine SAND (SM)
Reddish brown, moist, medium stiff, sandy LEAN CLAY (CL) wet
Boring was terminated at approximately 16.5 feet below existing ground surface.

Groundwater was encountered at approximately 15.0 feet below existing ground surface.

D35-1I
D35-2I
D35-3I
D35-4I
16 13
11 15
103
91 99

20.5 27.3

21.7 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 37

16.2 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
KRL
CME 75
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
9/28/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D35
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
15 BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:33 PM 1999
PP=4.5
PP=3.75
PP=3.0
Dark brown, moist, hard, silty LEAN CLAY (CL)
tanish brown, very stiff
slightly calcified
Boring was terminated at approximately 10.0 feet below existing ground surface.

Groundwater was not encountered.

D36-1I
D36-2I
D36-3I
10 33
18 101
109
104

19.5 13.2

19.4 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 38

10.0 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
KRL
CME 75
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
9/28/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D36
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:33 PM 2000
Brown to dark brown, moist, stiff, silty LEAN CLAY (CL) very stiff
light brown
Boring was terminated at approximately 10.0 feet below existing ground surface.

Groundwater was not encountered.

D37-1I
D37 @ 0-4'
D37-2I
D37-3I
13 28
29 93
107
112

24.9 18.9

19.7 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 39

10.0 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
JRY
CME 75
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
10/2/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D37
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:33 PM 2001
UCC=

2.6 tsf
UCC=

1.3 tsf
Light brown with black mottling, moist, stiff, silty LEAN CLAY (CL) very stiff
with sand
Boring was terminated at approximately 11.5 feet below existing ground surface.

Groundwater was not encountered.

D38 @ 0-4'
D38-1I
D38-2I
D38-3I
16 17
20 97
102

23.6 19.9
Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 40

11.5 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
JRY
CME 75
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
10/2/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D38
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:33 PM 2002
Dark brown, moist, stiff, silty LEAN CLAY (CL)
light brown to brown with black mottling, very stiff
Boring was terminated at approximately 10.0 feet below existing ground surface.

Groundwater was not encountered.

D39-1I
D39-2I
D39-3I
13 19
23 95
111
105

16.2 16.2

22.0 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 41

10.0 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
JRY
CME 75
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
10/2/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D39
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:33 PM 2003
PI
Light brown with gray mottling, moist, very stiff, silty LEAN CLAY (CL) with black mottling
stiff
Boring was terminated at approximately 16.5 feet below existing ground surface.

Groundwater was not encountered.

D40 @ 0-4'
D40-1I
D40-2I
D40-3I
D40-4I
23 19
11 15
102
101
87 18.8

23.7 34.6
Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 42

16.5 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
JRY
CME 75
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
10/2/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D40
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
15 BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:33 PM 2004
Dark brown, moist, medium stiff, LEAN CLAY (CL)
Grayish brown, moist, stiff, sandy LEAN CLAY (CL)
Boring was terminated at approximately 10.0 feet below existing ground surface.

Groundwater was not encountered.

D41-1I
D41-2I
D41-3I
9 14
12 102
110
86 18.8

17.7 31.3
Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 43

10.0 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
DB
CME 75
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
10/1/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D41
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:33 PM 2005
Light brown, moist, stiff, sandy LEAN CLAY (CL)
Light brown, moist, stiff, LEAN CLAY (CL)
Boring was terminated at approximately 10.0 feet below existing ground surface.

Groundwater was not encountered.

D42-1I
D42-2I
D42-3I
15 16
17 104
99 107

18.9 23.8

18.5 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 44

10.0 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
JRY
CME 75
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
10/2/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D42
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:33 PM 2006
Dark brown, moist, stiff, silty LEAN CLAY (CL)
Yellowish brown to brown with white and black mottling, very stiff Brown, moist, medium dense, silty SAND (SM)
Boring was terminated at approximately 10.0 feet below existing ground surface.

Groundwater was not encountered.

D43-1I
D43-2I
D43-3I
11 20
36 97
99 99

14.5 22.5

23.1 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 45

10.0 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
JRY
CME 75
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
10/2/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D43
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:33 PM 2007
HC
Brown with white and black mottling, moist, stiff, silty LEAN CLAY (CL) yellowish brown to brown with black mottling
no mottling, very stiff
Boring was terminated at approximately 16.5 feet below existing ground surface.

Groundwater was not encountered.

D44-1I
D44-2I
D44-3I
D44-4I
17 17
27 35
103
100

18.0 24.6
Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 46

16.5 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
JRY
CME 75
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
10/2/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D44
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
15 BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:33 PM 2008
Brown, moist, stiff, silty LEAN CLAY (CL)
white and black mottling, very stiff, trace sand
Boring was terminated at approximately 10.0 feet below existing ground surface.

Groundwater was not encountered.

D45-1I
D45-2I
D45-3I
12 30
28 103
113
102

16.0 10.9

22.8 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 47

10.0 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
JRY
CME 75
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
10/2/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D45
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:33 PM 2009
PI
PI
Dark brown, moist, stiff, LEAN CLAY (CL)
Yellowish brown, moist, very stiff, sandy silty LEAN CLAY (CL) slight calcification
increased plasticity
increased sand content
decreased sand content
D46-1I
D46-2I
D46-3I
D46-4I
D46-5I
D46-6I
14 23
24 17
20 26

18.6 20.3

20.3 17.8
Sheet 1 of 2
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 48

51.5 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Hollow Stem Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
DB
CME 75
V&W Drilling

SAMPLE DATA

ENGINEERING CLASSIFICATION AND DESCRIPTION
Date(s)
Drilled
8 ELEVATION, feetSAMPLE
Checked
By
Logged
By JRY
Drilling
Contractor
Groundwater Depth
[Elevation], feet
Diameter(s)
of Hole, inches
MOISTURECONTENT, %

TEST DATA

2.0" Modified California with 6-inch
sleeve
10/1/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D46
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
15 20
25 BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:33 PM 2010
PI
Brown, moist, medium dense, clayey fine to coarse SAND (SC) Brown, moist, hard, sandy LEAN CLAY (CL)
very stiff
Brown, moist, medium dense, clayey fine to coarse SAND (SC) with gravel, very dense
Boring was terminated at approximately 51.5 feet below existing ground surface.

Groundwater was not encountered.

D46-7I
D46-8I
D46-9I
D46-10I
D46-11I
36 37
28 28
57 13.3
ELEVATION, feetDEPTH, feetSAMPLESAMPLENUMBER
LOG OF SOIL BORING D46

TEST DATA

ENGINEERING CLASSIFICATION AND DESCRIPTION

2.5 tsf
Dark brown, moist, stiff, LEAN CLAY (CL)
Yellowish brown, moist, very stiff, sandy LEAN CLAY (CL) Brown, moist, medium dense, clayey fine SAND (SC)
Boring was terminated at approximately 10.0 feet below existing ground surface.

Groundwater was not encountered.

D47-1I
D47-2I
D47-3I
12 21
28 91
87 25.3

14.6 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 49

10.0 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
DB
CME 75
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
10/1/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D47
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:33 PM 2012
Dark brown, moist, stiff, LEAN CLAY (CL)
Grayish brown, moist, very stiff, sandy LEAN CLAY (CL)
Grayish brown, moist, medium dense, clayey SAND (SC)
Grayish brown, moist, hard, sandy LEAN CLAY (CL)
Boring was terminated at approximately 16.5 feet below existing ground surface.

Groundwater was not encountered.

D48-1I
D48-2I
D48-3I
D48-4I
16 26
36 36
96 100
94 18.8

27.7 25.6
Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 50

16.5 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
DB
CME 75
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
10/1/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D48
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
15 BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:33 PM 2013
Dark brown, moist, stiff, LEAN CLAY (CL)
Dark brown, moist, very stiff, sandy LEAN CLAY (CL); variably cemented Dark brown, moist, dense, clayey fine to coarse SAND with gravel (SC) Boring was terminated at approximately 10.0 feet below existing ground surface.

Groundwater was not encountered.

D49-1I
D49 @ 0-5'
D49-2I
D49-3I
14 31
46 93
110
114

15.9 13.0

10.8 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 51

10.0 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
DB
CME 75
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
10/1/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D49
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:33 PM 2014
Dark brown, moist, very stiff, silty LEAN CLAY (CL)
Brown, moist, very stiff, sandy LEAN CLAY (CL)
hard
Boring was terminated at approximately 16.5 feet below existing ground surface.

Groundwater was not encountered.

D50-1I
D50-2I
D50-3I
D50-4I
22 24
33 41
105
91 106

17.0 20.9

19.3 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 52

16.5 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
DB
CME 75
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
10/1/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D50
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
15 BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:33 PM 2015
Dark brown, moist, stiff, sandy LEAN CLAY (CL)
brown, hard
Boring was terminated at approximately 10.0 feet below existing ground surface.

Groundwater was not encountered.

D51-1I
D51-2I
D51-3I
10 39
43 87
88 110

17.9 14.2

17.7 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 53

10.0 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
DB
CME 75
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
10/1/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D51
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:33 PM 2016
PI
UCC=

4.1 tsf
Brown, moist, very stiff, sandy LEAN CLAY (CL)
hard
Boring was terminated at approximately 16.5 feet below existing ground surface.

Groundwater was not encountered.

D52-1I
D52-2I
D52-3I
D52-4I
30 42
44 37
106
110

14.6 16.4

16.8 Sheet 1 of 1
Project Location: American Canyon, California
Project: Green Island Logistics Center
WKA Number: 12883.01
FIGURE 54

16.5 feet
Sampling
Method(s)
Approx. Surface
Elevation, ft MSL
Solid Flight Auger GRAPHIC LOG

ADDITIONALTESTS
Drilling
Method
Drill Rig
Type
Total Depth
of Drill Hole
Drill Hole
Backfill
DB
CME 75
V&W Drilling

SAMPLE DATA

TEST DATA

2.0" Modified California with 6-inch
sleeve
10/1/20
DRY UNITWEIGHT, pcf
Driving Method
and Drop
140lb auto. hammer
with 30" drop
LOG OF SOIL BORING D52
DEPTH, feet
Remarks
Not Encountered Neat Cement SAMPLE NUMBER NUMBER OF BLOWS 5 10
15 BORING LOG 12883.01 - GREEN ISLAND LOGISTICS CENTER.GPJ WKA.GDT 11/6/20 3:33 PM 2017
55 11/2020

UNIFIED SOIL CLASSIFICATION SYSTEM

GREEN ISLAND ROAD LOGISTICS CENTER
American Canyon, California 12883.01
RWO
JRY
GHG
2018

APPENDICES
2019

APPENDIX A
General Project Information, Field and Laboratory Test Results 2020

APPENDIX A
WKA No. 12883.01
A. GENERAL INFORMATION
The performance of a geotechnical engineering study for the proposed warehouse buildings to be constructed north of Green Island Road in American Canyon, California was authorized by Mr. Troy Estacio on August 14, 2020. Authorization was for a study as described in our proposal letter dated August 8, 2020, sent to our client Buzz Oates Management Service, whose mailing address is 555 Capitol Mall, Suite 900, Sacramento, California, 95814; telephone (916) 379-8874. The project architect is RMW Architecture Interiors, whose mailing address is 1718 Third Street, Suite 101, Sacramento, California, 95811; telephone (916) 449-1400.

In preparing this report we referenced an August 8, 2020 Preliminary Concept Site Plan of the Green Island Road Logistics Center prepared by RMW Architecture Interiors. B. FIELD EXPLORATION 52 borings were drilled on September 21, 2020, September 22, 2020, September 28, 2020, September 29, 2020, October 1, 2020, and October 2, 2020, at the approximate locations indicated on Figure 2 to maximum depths of approximately 51½ feet below existing grades, utilizing a CME-55HT and a CME-75 truck-mounted drill rig equipped with six-inch diameter solid helical augers and eight-inch hollow stem augers. At various intervals, soil samples were recovered from the borings with a 2½-inch outside diameter (O.D.), 2-inch inside diameter (I.D.), modified California split-spoon sampler or a 2-inch O.D., 1⅜-inch I.D., Standard Penetration Test (SPT) split-spoon sampler. Both samplers were driven by an automatic 140-pound hammer freely falling 30 inches. The number of blows of the hammer required to drive the 18-inch long samplers each sixinch interval were recorded. The sum of the blows required to drive the sampler the lower 12-inch interval, or portion thereof, is designated the penetration resistance or "blow count" for that particular drive. The modified California samples were retained in 2-inch diameter by 6-inch long, thin walled brass tubes contained within the sampler.

The SPT samples were retained in plastic zip-lock bags. After recovery, the field representative visually classified the soil recovered in the tubes and plastic bags. After the samples were classified, the ends of the tubes and plastic bags were sealed to preserve the natural moisture contents.

In addition to the drive samples from the borings, representative bulk samples of near- surface soil were collected and retained in plastic bags at the locations, shown in Figure

2. All samples were taken to our laboratory for additional soil classification and selection of samples for testing.
2021
WKA No. 12883.01 Page A2
The Logs of Soil Borings containing descriptions of the soils encountered in each boring are presented as Figures 3 through 54. A Legend explaining the Unified Soil Classification System and the symbols used on the logs is contained in Figure 55. C. LABORATORY TESTING Selected undisturbed samples of the soils were tested to determine dry unit weight (ASTM D2937), natural moisture content (ASTM D2216), wash 200 grading (ASTM D1140), and unconfined compressive strength (ASTM D2166). The results of these tests are included on the boring logs at the depth each sample was obtained.

Samples of clay were subject to testing to determine the Atterberg Limits (ASTM D4318). The results of these tests are presented in Figure A1 through A4. Samples of the near-surface clay were also tested to determine the Expansion Index (ASTM D4829) with results presented in Figures A5 through A9. Bulk samples (one native sample and one lime-treated) of the near-surface soil were tested to determine the Resistance (“R”) Value (CT 301) with results presented in Figures A10 through A12. Two samples of the near-surface soil were submitted to Gulf Shore Exploration and Testing for Hydraulic Conductivity testing (ASTM D5084 Method F) with results presented in Figures A13 and A14.

Samples of the near-surface soils were submitted to Sunland Analytical for corrosivity testing in accordance with California Test (CT) 643, CT 422 and CT 417. A copy of the analytical results is presented on Figures A15 through A26. Two samples of the near-surface soils were tested for an optimum moisture and maximum dry density (ASTM D1557 Method A) the Compaction test results are presented in Figures A27 and A28.
2022

ATTERBERG LIMITS
ASTM D4318
CL - ML ML and OL
40 CL
CH
MH and OH
"A" Line
Liquid Limit
Plasticity Index
10 0
20 30
40 50
60 70
80 0 10 20 30 50 60 70 80 90 100 110 120
D3 0’-4.0’ --- 45 25 --- CL
KEY

SYMBOL LOCATION SAMPLE
DEPTH

NATURAL
WATER

CONTENT
(%)
LIQUID
LIMIT
(%)

PLASTICITY
INDEX
(%)

PASSING
No. 200
SIEVE
(%)

UNIFIED
SOIL
CLASSIFICATION
SYMBOL

ATTERBERG LIMITS
Wallace Kuhl & A S S O C I A T E S
D3-2 6'-6.5’ --- 45 27 --- CL
D3-5 21'-21.5’ --- 37 21 --- CL
D3-8 36'-36.5’ --- 38 21 --- CL
12883.01
A1
11/2020

ATTERBERG LIMITS

GREEN ISLAND ROAD LOGISTICS CENTER
American Canyon, California DATE

PROJECT MGR

CHECKED BY

DRAWN BY
FIGURE
WKA NO.

RWO
JRY
GHG
2023

ATTERBERG LIMITS
ASTM D4318
CL - ML ML and OL
40 CL
CH
MH and OH
"A" Line
Liquid Limit
Plasticity Index
10 0
20 30
40 50
60 70
80 0 10 20 30 50 60 70 80 90 100 110 120
D21 0’-4.0’ --- 42 25 --- CL
KEY

SYMBOL LOCATION SAMPLE
DEPTH

NATURAL
WATER

CONTENT
(%)
LIQUID
LIMIT
(%)

PLASTICITY
INDEX
(%)

PASSING
No. 200
SIEVE
(%)

UNIFIED
SOIL
CLASSIFICATION
SYMBOL

ATTERBERG LIMITS
Wallace Kuhl & A S S O C I A T E S
D21-1 3'-3.5’ --- 32 15 --- CL
D21-7 21'-21.5’ --- 44 26 --- CL
D26 0’-4.0’ --- 46 28 --- CL
12883.01
A2
11/2020

ATTERBERG LIMITS

GREEN ISLAND ROAD LOGISTICS CENTER
American Canyon, California DATE

PROJECT MGR

CHECKED BY

DRAWN BY
FIGURE
WKA NO.

RWO
JRY
GHG
2024

ATTERBERG LIMITS
ASTM D4318
CL - ML ML and OL
40 CL
CH
MH and OH
"A" Line
Liquid Limit
Plasticity Index
10 0
20 30
40 50
60 70
80 0 10 20 30 50 60 70 80 90 100 110 120
D32-2 6'-6.5’ --- 34 16 --- CL
KEY

SYMBOL LOCATION SAMPLE
DEPTH

NATURAL
WATER

CONTENT
(%)
LIQUID
LIMIT
(%)

PLASTICITY
INDEX
(%)

PASSING
No. 200
SIEVE
(%)

UNIFIED
SOIL
CLASSIFICATION
SYMBOL

ATTERBERG LIMITS
Wallace Kuhl & A S S O C I A T E S
D32-5 21'-21.5’ --- 48 29 --- CL
D32-8 36'-36.5’ --- 40 18 --- CL
D40 0’-4.0’ --- 39 23 --- CL
12883.01
A3
11/2020

ATTERBERG LIMITS

GREEN ISLAND ROAD LOGISTICS CENTER
American Canyon, California DATE

PROJECT MGR

CHECKED BY

DRAWN BY
FIGURE
WKA NO.

RWO
JRY
GHG
2025

ATTERBERG LIMITS
ASTM D4318
CL - ML ML and OL
40 CL
CH
MH and OH
"A" Line
Liquid Limit
Plasticity Index
10 0
20 30
40 50
60 70
80 0 10 20 30 50 60 70 80 90 100 110 120
D46-2 6'-6.5’ --- 35 18 --- CL
KEY

SYMBOL LOCATION SAMPLE
DEPTH

NATURAL
WATER

CONTENT
(%)
LIQUID
LIMIT
(%)

PLASTICITY
INDEX
(%)

PASSING
No. 200
SIEVE
(%)

UNIFIED
SOIL
CLASSIFICATION
SYMBOL

ATTERBERG LIMITS
Wallace Kuhl & A S S O C I A T E S
D46-5 21'-21.5’ --- 36 19 --- CL
D46-8 36'-36.5’ --- 45 27 --- CL
D52 0’-4.0’ --- 48 29 --- CL
12883.01
A4
11/2020

ATTERBERG LIMITS

GREEN ISLAND ROAD LOGISTICS CENTER
American Canyon, California DATE

PROJECT MGR

CHECKED BY

DRAWN BY
FIGURE
WKA NO.

RWO
JRY
GHG
2026
Wallace Kuhl & A S S O C I A T E S 12883.01
A5
11/2020

EXPANSION INDEX

GREEN ISLAND ROAD LOGISTICS CENTER
American Canyon, California DATE

PROJECT MGR

CHECKED BY

DRAWN BY
FIGURE
WKA NO.

Sample
Depth
Pre-Test
Moisture (%)
Post-Test
Moisture (%)
Dry Density
(pcf)
Expansion
Index

EXPANSION INDEX
0 - 20
21 - 50
51 - 90
91 - 130
Above 130 Very High
High
Medium
Low
Very Low

POTENTIAL EXPANSION

EXPANSION INDEX TEST RESULTS
MATERIAL DESCRIPTION:

LOCATION:

CLASSIFICATION OF EXPANSIVE SOIL *
* From ASTM D4829, Table 1
ASTM D4829
Dark brown, silty lean clay
D3
0’ - 4’ 14.5 29.7 93 39
RWO
JRY
GHG
2027
Wallace Kuhl & A S S O C I A T E S 12883.01
A6
11/2020

EXPANSION INDEX

GREEN ISLAND ROAD LOGISTICS CENTER
American Canyon, California DATE

PROJECT MGR

CHECKED BY

DRAWN BY
FIGURE
WKA NO.

Sample
Depth
Pre-Test
Moisture (%)
Post-Test
Moisture (%)
Dry Density
(pcf)
Expansion
Index

EXPANSION INDEX
0 - 20
21 - 50
51 - 90
91 - 130
Above 130 Very High
High
Medium
Low
Very Low

POTENTIAL EXPANSION

EXPANSION INDEX TEST RESULTS
MATERIAL DESCRIPTION:

LOCATION:

CLASSIFICATION OF EXPANSIVE SOIL *
* From ASTM D4829, Table 1
ASTM D4829
Brown, sandy lean clay
D21
0’ - 4’ 11.5 21.9 105 33
RWO
JRY
GHG
2028
Wallace Kuhl & A S S O C I A T E S 12883.01
A7
11/2020

EXPANSION INDEX

GREEN ISLAND ROAD LOGISTICS CENTER
American Canyon, California DATE

PROJECT MGR

CHECKED BY

DRAWN BY
FIGURE
WKA NO.

Sample
Depth
Pre-Test
Moisture (%)
Post-Test
Moisture (%)
Dry Density
(pcf)
Expansion
Index

EXPANSION INDEX
0 - 20
21 - 50
51 - 90
91 - 130
Above 130 Very High
High
Medium
Low
Very Low

POTENTIAL EXPANSION

EXPANSION INDEX TEST RESULTS
MATERIAL DESCRIPTION:

LOCATION:

CLASSIFICATION OF EXPANSIVE SOIL *
* From ASTM D4829, Table 1
ASTM D4829
Dark reddish brown, silty lean clay
D26
0’ - 4’ 12.0 25.6 104 95
RWO
JRY
GHG
2029
Wallace Kuhl & A S S O C I A T E S 12883.01
A8
11/2020

EXPANSION INDEX

GREEN ISLAND ROAD LOGISTICS CENTER
American Canyon, California DATE

PROJECT MGR

CHECKED BY

DRAWN BY
FIGURE
WKA NO.

Sample
Depth
Pre-Test
Moisture (%)
Post-Test
Moisture (%)
Dry Density
(pcf)
Expansion
Index

EXPANSION INDEX
0 - 20
21 - 50
51 - 90
91 - 130
Above 130 Very High
High
Medium
Low
Very Low

POTENTIAL EXPANSION

EXPANSION INDEX TEST RESULTS
MATERIAL DESCRIPTION:

LOCATION:

CLASSIFICATION OF EXPANSIVE SOIL *
* From ASTM D4829, Table 1
ASTM D4829
Light brown, silty lean clay
D40
0’ - 4’ 11.0 25.7 105 108
RWO
JRY
GHG
2030
Wallace Kuhl & A S S O C I A T E S 12883.01
A9
11/2020

EXPANSION INDEX

GREEN ISLAND ROAD LOGISTICS CENTER
American Canyon, California DATE

PROJECT MGR

CHECKED BY

DRAWN BY
FIGURE
WKA NO.

Sample
Depth
Pre-Test
Moisture (%)
Post-Test
Moisture (%)
Dry Density
(pcf)
Expansion
Index

EXPANSION INDEX
0 - 20
21 - 50
51 - 90
91 - 130
Above 130 Very High
High
Medium
Low
Very Low

POTENTIAL EXPANSION

EXPANSION INDEX TEST RESULTS
MATERIAL DESCRIPTION:

LOCATION:

CLASSIFICATION OF EXPANSIVE SOIL *
* From ASTM D4829, Table 1
ASTM D4829
Brown, sand lean clay
D52
0’ - 4’ 11.0 25.7 105 101
RWO
JRY
GHG
2031
12883.01

GREEN ISLAND ROAD LOGISTICS CENTER
American Canyon, California
A10
11/2020

RESISTANCE VALUE TEST RESULTS

RESISTANCE VALUE TEST RESULTS
(California Test 301)
MATERIAL DESCRIPTION:

LOCATION:

Dry Unit
Weight
(pcf)
Specimen
No.

Moisture
@ Compaction
(%)
Exudation
(psi)
Pressure Expansion
(dial, inches x 1000) Value
R
(psf)
1 1
3 2
(psf)
R
Value
Pressure Expansion
(psi)
Exudation
(%)
@ Compaction
Moisture
No.

Specimen
(pcf)
Weight
Dry Unit
LOCATION:

MATERIAL DESCRIPTION:

Dark brown, silty lean clay
B1 (0’ - 4’)
109 18.2 686 49 212 *
*
R-Value at 300 psi exudation pressure = 82
Dark brown, silty lean clay with 4% lime added
B1 (0’ - 4’)
104
105
103

21.7 21.4

22.4 355
477
255
35 43
26 83
84 81
Sample extruded, therefore R-Value = 5
(dial, inches x 1000)
8 10
6 RWO
JRY
GHG
2032
12883.01

GREEN ISLAND ROAD LOGISTICS CENTER
American Canyon, California
A11
11/2020

RESISTANCE VALUE TEST RESULTS

RESISTANCE VALUE TEST RESULTS
(California Test 301)
MATERIAL DESCRIPTION:

LOCATION:

Dry Unit
Weight
(pcf)
Specimen
No.

Moisture
@ Compaction
(%)
Exudation
(psi)
Pressure Expansion
(dial, inches x 1000) Value
R
(psf)
1 1
3 2
(psf)
R
Value
Pressure Expansion
(psi)
Exudation
(%)
@ Compaction
Moisture
No.

Specimen
(pcf)
Weight
Dry Unit
LOCATION:

MATERIAL DESCRIPTION:

Brown, silty lean clay
B2 (0’ - 4’)
115 15.2 604 31 134 *
*
R-Value at 300 psi exudation pressure = 84
Brown, silty lean clay with 4% lime added
B2 (0’ - 4’)
109
110
108

17.5 17.7

18.1 360
313
251
87 91
95 85
84 83
Sample extruded, therefore R-Value = 5
(dial, inches x 1000)
20 21
22 RWO
JRY
GHG
2033
12883.01

GREEN ISLAND ROAD LOGISTICS CENTER
American Canyon, California
A12
11/2020

RESISTANCE VALUE TEST RESULTS

RESISTANCE VALUE TEST RESULTS
(California Test 301)
MATERIAL DESCRIPTION:

LOCATION:

Dry Unit
Weight
(pcf)
Specimen
No.

Moisture
@ Compaction
(%)
Exudation
(psi)
Pressure Expansion
(dial, inches x 1000) Value
R
(psf)
1 1
3 2
(psf)
R
Value
Pressure Expansion
(psi)
Exudation
(%)
@ Compaction
Moisture
No.

Specimen
(pcf)
Weight
Dry Unit
LOCATION:

MATERIAL DESCRIPTION:

Dark brown, lean clay
B3 (0’ - 4’)
112 17.4 638 34 147 *
*
R-Value at 300 psi exudation pressure = 84
Dark brown, lean clay with 4% lime added
B3 (0’ - 4’)
122
122
120

4.9 5.4

5.8 350
294
255
17 4
0 87
83 77
Sample extruded, therefore R-Value = 5
(dial, inches x 1000)
4 1
0 RWO
JRY
GHG
2034

GREEN ISLAND ROAD LOGISTICS CENTER
American Canyon, California
A13
11/2020

HYDRAULIC CONDUCTIVITY TEST RESULTS
12883.01
RWO
JRY
GHG
2035

GREEN ISLAND ROAD LOGISTICS CENTER
American Canyon, California
11/2020

HYDRAULIC CONDUCTIVITY TEST RESULTS
12883.01
RWO
JRY
GHG A14
2036

GREEN ISLAND ROAD LOGISTICS CENTER
American Canyon, California
11/2020

CORROSION TEST RESULTS
12883.01
RWO
JRY
GHG
A15
2037

GREEN ISLAND ROAD LOGISTICS CENTER
American Canyon, California
11/2020

CORROSION TEST RESULTS
12883.01
A16
RWO
JRY
GHG
2038

GREEN ISLAND ROAD LOGISTICS CENTER
American Canyon, California
11/2020

CORROSION TEST RESULTS
12883.01
A17
RWO
JRY
GHG
2039

GREEN ISLAND ROAD LOGISTICS CENTER
American Canyon, California
11/2020

CORROSION TEST RESULTS
12883.01 A18
RWO
JRY
GHG
2040

GREEN ISLAND ROAD LOGISTICS CENTER
American Canyon, California
11/2020

CORROSION TEST RESULTS
12883.01 A19
RWO
JRY
GHG
2041

GREEN ISLAND ROAD LOGISTICS CENTER
American Canyon, California
11/2020

CORROSION TEST RESULTS
12883.01
A20
RWO
JRY
GHG
2042

GREEN ISLAND ROAD LOGISTICS CENTER
American Canyon, California
11/2020

CORROSION TEST RESULTS
12883.01
A21
RWO
JRY
GHG
2043

GREEN ISLAND ROAD LOGISTICS CENTER
American Canyon, California
11/2020

CORROSION TEST RESULTS
12883.01
RWO
JRY
GHG A22
2044

GREEN ISLAND ROAD LOGISTICS CENTER
American Canyon, California 11/2020

CORROSION TEST RESULTS
12883.01 A23
RWO
JRY
GHG
2045

GREEN ISLAND ROAD LOGISTICS CENTER
American Canyon, California
11/2020

CORROSION TEST RESULTS
12883.01 A24
RWO
JRY
GHG
2046

GREEN ISLAND ROAD LOGISTICS CENTER
American Canyon, California
11/2020

CORROSION TEST RESULTS
12883.01 A25
RWO
JRY
GHG
2047

GREEN ISLAND ROAD LOGISTICS CENTER
American Canyon, California
A26
RWO
JRY
GHG
11/2020

CORROSION TEST RESULTS
12883.01
2048

MOISTURE-DENSITY RELATION
127
122
I 117
-� ---r----....._
3: 10"' I"-
!::: "-::i
z 112 '""'-- :::, "" �
"
107 "�
102
8 10 12 14 16 18 20
MOISTURE CONTENT - %
Material: Dark reddish brown, sandy lean clay
Location: D15 (0'-5')
Test Method: ASTM D1557 "A"
Maximum Dry Unit Weight -PCF: 116.0
Optimum Moisture - %: 12.4
''' FIGURE A27

COMPACTION CURVE DRAWN BY RWO

CHECKED BY JRY

GREEN ISLAND ROAD LOGISTICS CENTER PROJECT MGR GHG
WallaceKuhl American Canyon, California DATE 11/2020
& ASSOCIATES WKA NO. 12883.01
2049

MOISTURE-DENSITY RELATION
112
110 oV----
"'
/ [\
LL / \
0 CL I \
V I \
108
::c I
I
I
I
z
:::, 106 I \ � I \ C �
\
104 \
102
6 8 10 12 14 16 18
MOISTURE CONTENT - %
Material: Light brown, silty lean clay
Location: D38 (O' - 4')
Test Method: ASTM D1557 "A"
Maximum Dry Unit Weight - PCF: 110.5
Optimum Moisture - %: 11.6
''' FIGURE A28

COMPACTION CURVE DRAWN BY RWO

CHECKED BY JRY

GREEN ISLAND ROAD LOGISTICS CENTER PROJECT MGR GHG
WallaceKuhl American Canyon, California DATE 11/2020
& ASSOCIATES WKA NO. 12883.01
2050

APPENDIX B
Guide Earthwork Specifications
2051

APPENDIX B

GUIDE EARTHWORK SPECIFICATIONS

GREEN ISLAND ROAD LOGISTICS CENTER
American Canyon, California
WKA No. 12883.01
PART 1: GENERAL

1.1 SCOPE
a. General Description
This item shall include all clearing of existing surface and subsurface structures, utilities, vegetation, rubbish, rubble, stockpiles and associated items; preparation of surfaces to be filled, filling, spreading, compaction, observation and testing of the fill; and all subsidiary work necessary to complete the grading of the site to conform with the lines, grades and slopes as shown on the accepted Drawings. b. Related Work Specified Elsewhere
(1) Trenching and backfilling for sanitary sewer system: Section . (2) Trenching and backfilling for storm drain system: Section . (3) Trenching and backfilling for underground water, natural gas, and electric supplies: Section . c. Geotechnical Engineer
Where specific reference is made to "Geotechnical Engineer" this designation shall be understood to include both the firm and the individual representatives of that firm, retained to provide geotechnical testing and inspection services during construction.

1.2 PROTECTION
a. Adequate protection measures shall be provided to protect workers and passers- by the site. Streets and adjacent property shall be fully protected throughout the operations.
b. In accordance with generally accepted construction practices, the Contractor shall be solely and completely responsible for working conditions at the job site, including safety of all persons and property during performance of the work. This requirement shall apply continuously and shall not be limited to normal working hours.
c. Any construction review of the Contractor's performance conducted by the Geotechnical Engineer is not intended to include review of the adequacy of the Contractor's safety measures, in, on or near the construction site. d. Adjacent streets and sidewalks shall be kept free of mud, dirt, or similar nuisances resulting from earthwork operations.
2052
WKA No. 11883.01 Page B2
e. Measures shall be taken to protect storm drains in adjacent depressed areas such that minimum siltation occurs in the drainage system. f. Surface drainage provisions shall be made during the period of construction in a manner to avoid creating a nuisance to adjacent areas.
g. The site and adjacent influenced areas shall be watered as required to suppress dust nuisance.

1.3 GEOTECHNICAL REPORT
a. A Geotechnical Engineering Report (WKA No. 12883.01; dated November 10, 2020) has been prepared for this site by Wallace - Kuhl & Associates, Geotechnical Engineers of West Sacramento, California [(916) 372-1434]. A copy is available for review at the office of Wallace - Kuhl & Associates. b. The information contained in this report was obtained for design purposes only.

The contractor is responsible for any conclusions they may draw from this report.

Should it be preferred not to assume such risk, they should employ their own experts to analyze available information and/or to make additional borings upon which to base conclusions, all at no cost to the Owner.

1.4 EXISTING SITE CONDITIONS
The Contractor shall become acquainted with all site conditions. If unshown active utilities are encountered during the work, the Architect shall be promptly notified for instructions. Failure to notify will make the Contractor liable for damage to these utilities arising from Contractor's operations subsequent to the discovery of such unshown utilities.

1.5 SEASONAL LIMITS
Fill material shall not be placed, spread or rolled during unfavorable weather conditions.

When the work is interrupted by heavy rains, fill operations shall not be resumed until field tests indicate that the moisture contents of the subgrade and fill materials are satisfactory.

PART 2: PRODUCTS

2.1 MATERIALS
a. All fill shall be of approved local materials from required excavations, supplemented by imported fill, if necessary. Approved local materials are defined as local soils that do not contain significant quantities of rubble, rubbish and vegetation, and having been tested and approved by the Geotechnical Engineer prior to use.
b. Imported fill materials shall be approved by the Geotechnical Engineer; they shall be compactable materials meeting the above requirements; shall have a Plasticity Index not exceeding fifteen (15) when tested in accordance with ASTM D4318, an expansion index not exceeding twenty (20) when tested in 2053
WKA No. 11883.01 Page B3
accordance with ASTM D4829; and, shall be of three-inch (3") maximum particle size. Import materials also shall not contain known contaminants and be within acceptable corrosion limits, with appropriate documentation provided by the contractor.
c. Materials to be lime-treated shall be on-site clayey soils free from significant quantities of rubble, rubbish and vegetation and shall have been tested and approved by the Geotechnical Engineer.
d. Capillary barrier material under floor slabs shall be provided to the thickness shown on the Drawings. This material shall be clean gravel or crushed rock of one-inch (1") maximum size, with less than five percent (5%) material passing a Number Four (#4) sieve.
e. Lime used for stabilization shall be high-calcium or dolomitic quicklime conforming to the definitions in ASTM Designation C977. 1) When sampled by the Geotechnical Engineer from the lime spreader or during the spreading operations, the sample of lime shall conform to the following requirements:

Lime Quality
Property ASTM Designation Requirements
Available calcium and
magnesium oxide
[minimum percent (%)]
C25
or
C1301 & C1271
High calcium quicklime:

CaO > 90%
Dolomitic quicklime:

CaO > 55% & CaO + MgO > 90%
Loss on ignition
[maximum percent (%)] C25
7% (total loss)
5% (carbon dioxide)
2% (free moisture)
Slaking Rate
[degrees Celsius (°C)]
C110 30°C rise in 8 minutes
2) When dry sieved in a mechanical sieve shaker for 10 minutes +30 seconds, a

0.5 pound (lb) test sample of quicklime shall conform to the following grading requirements:

Lime Grading
Sieve Sizes Percentage Passing
3/8-inch 98 - 100
f. The burden of proof as to quality and suitability of alternatives shall be upon the Contractor and/or Supplier and he shall furnish test data and all information necessary, as required by the Geotechnical Engineer. Written request for alternatives, accompanied by complete data as to the quality and suitability of the 2054
WKA No. 11883.01 Page B4
material shall be made in ample time to permit testing and approval without delaying the work. The Geotechnical Engineer shall be the sole judge as to the quality and suitability of alternatives and his decision shall be final.

Documentation shall be provided to the Geotechnical Engineer no later than two weeks before the alternative material is imported to the site. g. Lime from more than one source or of more than one type may be used on the same project but the different limes shall not be mixed. h. The lime shall be protected from moisture until used and shall be sufficiently dry to flow freely when handled.
i. Water for use in subgrade stabilization shall be clean and potable and shall be added during mixing, remixing and compaction operations, and during the curing period to keep the cured material moist until covered.
j. Other products, such as aggregate base, asphalt concrete and related asphaltic seal coats, tack coat, etc., shall comply with the appropriate provision of the State of California (Caltrans) Standard Specifications, latest edition.

PART 3: EXECUTION

3.1 LAYOUT AND PREPARATION
Lay out all work, establish grades, locate existing underground utilities, set markers and stakes, set up and maintain barricades and protection of utilities prior to beginning actual earthwork operations.

3.2 CLEARING, STRIPPING, AND PREPARING STUCTURAL AREAS
a. All surface and other sub-surface items associated with previous site activities (including utilities) and associated backfill, vegetation, debris, and other items encountered during site work and deemed unacceptable by the Geotechnical Engineer, shall be removed and disposed of so as to leave the disturbed areas with a neat and finished appearance, free from unsightly debris. Vegetation designated for removal shall include the rootball and all surface roots larger than one-half inch (½”) in diameter. Adequate removal of debris and roots may require laborers and handpicking to clean the subgrade soils to the satisfaction of the Geotechnical Engineer’s on-site representative, prior to further site preparation. All demolition debris shall be hauled off site, or used as engineered fill, provided it is processed per the recommendations in Geotechnical Report. b. On-site wells or septic systems/tanks associated with previous development, if any, should be properly abandoned in accordance with Sacramento County Environmental Management requirements.
2055
WKA No. 11883.01 Page B5
c. Excavations and depressions resulting from the removal of such items, as determined by the Geotechnical Engineer, shall be cleaned out to firm, undisturbed soils and backfilled with suitable materials in accordance with these specifications.
d. All structural areas (building pads, pavements, exterior flatwork, etc.) shall be stripped of vegetation and organically laden topsoil. With prior approval of the Geotechnical Engineer and Owner, stripping may be used in landscaped areas, provided they are kept at least five (5) from building pads and other surface improvements, moisture conditioned and compacted.
e. Existing pavements designated for removal may be broken up, pulverized and reused as engineered fill, or removed from the site. If existing pavement rubble is reused as engineered fill, they shall be pulverized to fragments less than three inches (3”) in largest dimension and mixed with soil to for a compactable mixture. f. Sub-excavation to remove existing stockpiled soil, if any, and near-surface soils within the building pads and other structural areas (e.g. pavements, exterior flatwork, sidewalks, wall foundations, etc.) shall be performed as recommended in the Geotechnical Engineering Report.
g. The bottom of the required excavations, as well as areas to receive fill, achieved by excavation or remain at grade, should be scarified twelve inches (12”), uniformly moisture conditioned to at least two percent (2%) above the optimum moisture content for clay soils, and uniformly compacted to at least ninety percent (90%) of the maximum dry density as determined by ASTM D1557 Test Method.
h. Compaction operations for all soil subgrades shall be undertaken with a heavy, self-propelled, sheepsfoot compactor capable of achieving the compaction requirements included in the Geotechnical Engineering Report. i. When the moisture content of the fill material is less than two percent (2%) above the optimum moisture content as defined by the ASTM D1557 Compaction Test, water shall be added until the proper moisture content is achieved. j. When the moisture content of the subgrade is too high to permit the specified compaction to be achieved, the subgrade shall be aerated by blading or other methods until the moisture content is satisfactory for compaction. k. Compaction operations shall be performed in the presence of the Geotechnical Engineer who will evaluate the performance of the materials under compactive load. Loose, soft and saturated soils and unstable soil deposits, as determined by the Geotechnical Engineer, shall be excavated to expose a firm base and grades restored with engineered fill in accordance with these specifications. 2056
WKA No. 11883.01 Page B6

3.3 CONSTRUCTION OF UNTREATED SUBGRADES
a. The selected soil fill material shall be placed in layers which when compacted shall not exceed six inches (6") in compacted thickness. Each layer shall be spread evenly and shall be thoroughly mixed during the spreading to promote uniformity of material in each layer.
b. When the moisture content of the fill material is less than the optimum moisture content for granular/silty soils or at least two percent (2%) above the optimum moisture content for clay soils, as defined by the ASTM D1557 Compaction Test, water shall be added until the proper moisture content is achieved. c. When the moisture content of the fill material is too high to permit the specified degree of compaction to be achieved, the fill material shall be aerated by blading or other methods until the moisture content is satisfactory. d. After each layer has been placed, mixed and spread evenly, it shall be thoroughly compacted to at least ninety percent (90%) as determined by the ASTM D1557 Compaction Test. Compaction shall be undertaken with equipment capable of achieving the specified density and shall be accomplished while the fill material is at the required moisture content. Each layer shall be compacted over its entire area until the desired density has been obtained. e. The filling operations shall be continued until the fills have been brought to the finished slopes and grades as shown on the accepted Drawings.

3.4 LIME-STABLIZED SUBGRADE CONSTRUCITON
a. On-site clay material to be treated shall be placed at a moisture content at least two percent (2%) over optimum moisture as defined by the ASTM D1557 Compaction Test.
b. Material to be treated shall be scarified and thoroughly broken up to the full depth and width to be stabilized. The material to be treated shall contain no rocks or solids larger than one and one-half inches (1½") in maximum dimension. c. Mixing lime-treated material shall consist of the following:
1) Lime shall be added to the material to be treated at a rate of no less than four and one-half pounds (4½ lbs.) of lime per square foot of soil treated, to a depth sufficient to result in a twelve-inch (12”) layer of compacted lime treated soil. 2) Lime shall be spread by equipment that will uniformly distribute the required amount of lime for the full width of the prepared material. The rate of spread per linear foot of blanket shall not vary more than five percent (5%) from the designated rate.
3) The spread lime shall be prevented from blowing by suitable means selected by the Contractor. Quicklime shall not be used to make lime slurry. The spreading operations shall be conducted in such a manner that a hazard is not present to construction personnel or the public. All lime spread shall be 2057
WKA No. 11883.01 Page B7
thoroughly ripped in, or mixed into, the soil the same day lime spreading operations are performed.
4) The distance which lime may be spread upon the prepared material ahead of the mixing operation will be determined by the Geotechnical Engineer. 5) No traffic other than the mixing equipment will be allowed to pass over the spread lime until after the completion of mixing.
6) Mixing equipment shall be equipped with a visual depth indicator showing mixing depth, an odometer or foot meter to indicate travel speed and a controllable water additive system for regulating water added to the mixture. 7) Mixing equipment shall be of the type that can mix the full depth of the treatment specified and leave a relatively smooth bottom of the treated section.

Mixing and re-mixing, regardless of equipment used, will continue until the material is uniformly mixed (free of streaks or pockets of lime), moisture is at approximately two percent (2%) over optimum and the mixture complies with the following requirements:

Minimum
Sieve Size Percent Passing
1-1/2" 100
1" 95
No. 4 60
8) Non-uniformity of color reaction when the treated material, exclusive of one inch or larger clods, as tested with the standard phenolphthalein alcohol indicator, will be considered evidence of inadequate mixing. 9) Lime-treated material shall not be mixed or spread while the atmospheric temperature is below 35 degrees Fahrenheit (35°F). 10) Remixing of the treated soils shall be performed no sooner than twenty-four (24) hours after the initial mixing, and no later than seventy-two (72) hours after the initial mixing. The entire mixing operation shall be completed within seventytwo (72) hours of the initial spreading of lime, unless otherwise permitted by the Geotechnical Engineer.
d. Spreading and compacting of lime-treated material shall consist of the following:
1) The treated mixture shall be spread to the required width, grade and cross- section. The maximum compacted thickness of a single layer may be determined by the Contractor provided he can demonstrate to the Geotechnical Engineer that his equipment and method of operation will provide uniform distribution of the lime and the required compacted density throughout the layer. If the Contractor is unable to achieve uniformity and density throughout the thickness 2058
WKA No. 11883.01 Page B8
selected, he shall rework the affected area using thinner lifts until a satisfactory treated subgrade meeting the distribution and density requirements is attained, as determined by the Geotechnical Engineer, at no additional cost to the Owner. 2) The finished thickness of the lime-treated material shall not vary more than one-tenth foot (0.1') from the planned thickness at any point. 3) The lime-treated soils shall be compacted to a relative compaction of not less than ninety percent (90%) within building pads and exterior flatwork areas, and ninety-five percent (95%) within pavement areas, as determined by the ASTM D1557 Compaction Test.
4) Initial compaction shall be performed by means of a sheepsfoot or segmented wheel roller. Final rolling shall be by means of steel-tired or pneumatic-tired rollers.
5) Areas inaccessible to rollers shall be compacted to meet the minimum compaction requirement by other means satisfactory to the Geotechnical Engineer.
6) Final compaction shall be completed within thirty-six (36) hours of final mixing, and within four (4) hours of the final mixing. The surface of the finished limetreated material shall be the grading plane and at any point shall not vary more than eight one hundredths of a foot (0.08') foot above or below the grade established by the Civil Engineer except that when the lime-treated material is to be covered by material which is paid for by the cubic yard the surface of the finished lime-treated material shall not extend above the grade established by the Civil Engineer.
7) Before final compaction, if the treated material is above the grade tolerance specified in this section, uncompacted excess material may be removed and used in areas inaccessible to mixing equipment. After final compaction and trimming, excess material shall be removed and disposed of off site. The trimmed and completed surface shall be rolled with steel or pneumatic-tired rollers. Minor indentations may remain in the surface of the finished material so long as no loose material remains in the indentations.
8) At the end of each day's work, a construction joint shall be made in thoroughly compacted material and with a vertical face. After a partial-width section has been completed, the longitudinal joint against which additional material is to be placed shall be trimmed approximately three inches (3") into treated material, to the neat line of the section, with a vertical edge. The material so trimmed shall be incorporated into the adjacent material to be treated. 9) An acceptable alternate to the above construction joints, if the treatment is performed with cross shaft rotary mixers, is to actually mix three inches (3") into the previous day's work to assure a good bond to the adjacent work. 2059
WKA No. 11883.01 Page B9

3.5 FINAL SUBGRADE PREPARATION USING UNTREATED SOILS
a. Final subgrade for building pads and exterior flatwork shall be constructed in accordance with Section 3.2 and Section 3.3 of these specifications. Clay soils shall not be used in fills within the upper twelve inches (12”) of the final concrete foundation slabs or exterior flatwork subgrade, unless the limetreatment alternative include in the Geotechnical Engineering Report is selected. The upper twelve inches (12") of final subgrade for the interior and exterior concrete slabs and exterior flatwork shall consist of compactable, non- expansive, granular soils, be brought to a uniform moisture content not less than the optimum moisture content, and shall be uniformly compacted to not less than ninety percent (90%) as determined by ASTM D1557 Compaction Test, unless the lime-treatment alternative include in the Geotechnical Engineering Report is selected.
b. The upper six inches (6”) of any untreated final pavement subgrades shall be brought to at least two percent (2%) above the optimum moisture content, and uniformly compacted to at least ninety percent (90%) as determined by ASTM D1557 Compaction Test, regardless of whether final subgrade elevations are attained by filling, excavation or are left at existing grades.

3.6 FINAL SUBGRADE PREPARATION USING TREATED SOILS
a. Final subgrade for building pads and exterior flatwork using treated soils shall be constructed in accordance with Section 3.2 and Section 3.4 of these specifications. The upper twelve inches (12”) of treated final subgrades for building pads shall be brought to a uniform moisture content of at least two percent (2%) above the optimum moisture content, and shall be uniformly compacted to not less than ninety percent (90%) as determined by ASTM D1557 Compaction Test, regardless of whether final subgrade elevations are attained by filling, excavation or are left at existing grades.
b. Final subgrade for pavements using treated soils shall be constructed in accordance with Section 3.2 and Section 3.4 of these specifications. The upper twelve inches (12”) of treated final exterior flatwork and pavement subgrades shall be brought to a uniform moisture content of at least two percent (2%) above the optimum moisture content, and shall be uniformly compacted to not less than ninety-five percent (95%) as determined by ASTM D1557 Compaction Test, regardless of whether final subgrade elevations are attained by filling, excavation or are left at existing grades.

3.7 TESTING AND OBSERVATION
a. Grading operations shall be observed by the Geotechnical Engineer, serving as the representative of the Owner.
2060
WKA No. 11883.01 Page B10
b. Field density tests shall be made by the Geotechnical Engineer after compaction of each layer of fill. Additional layers of fill shall not be spread until the field density tests indicate that the minimum specified density has been obtained. c. Earthwork shall not be performed without the notification or approval of the Geotechnical Engineer. The Contractor shall notify the Geotechnical Engineer at least two (2) working days prior to commencement of any aspect of the site earthwork.
d. If the Contractor should fail to meet the technical or design requirements embodied in this document and on the applicable plans, the necessary readjustments shall be made by the Contractor until all work is deemed satisfactory, as determined by the Geotechnical Engineer and the Architect/Engineer. No deviation from the specifications shall be made except upon written approval of the Geotechnical Engineer or Architect/Engineer. //
2061
TYPE OF SERVICES Geological Fault Investigation
New Sanitary Sewer Main
PROJECT NAME Giovannoni Property
LOCATION Devlin Road
American Canyon, California
CLIENT Orchard Partners, LLC
PROJECT NUMBER 582-4-1
DATE November 2, 2017
2062
Type of Services Geological Fault Investigation
New Sanitary Sewer Main
Project Name Giovannoni Property
Location Devlin Road
American Canyon, California
Client Orchard Partners, LLC
Client Address 3697 Mt. Diablo Boulevard, Suite 200
Lafayette, California
Project Number 582-4-1
Date November 2, 2017

Prepared by Ryan A. McKee, P.G.

Project Geologist

Prepared by Craig Harwood, C.E.G.

Consulting Geologist

Nicholas S. Devlin, P.E.

Project Engineer
Quality Assurance Reviewer
2063

GIOVANNONI PROPERTY
582-4-1
Page i

TABLE OF CONTENTS
SECTION 1: INTRODUCTION........................................................................................................1

1.1 Project Description ----------------------------------------------------------------------------------------- 1

1.2 Scope of Services ------------------------------------------------------------------------------------------- 1

1.3 Ground Water Exploration Program ------------------------------------------------------------------ 2

1.4 Fault Investigation Exploration Program------------------------------------------------------------ 2

1.5 Environmental Services ----------------------------------------------------------------------------------- 3 SECTION 2: REGIONAL SETTING................................................................................................3

2.1 Regional Geologic Setting-------------------------------------------------------------------------------- 3

2.2 Local Geology ------------------------------------------------------------------------------------------------ 3

2.3 Regional Seismicity----------------------------------------------------------------------------------------- 4 Table 1: Approximate Fault Distances ....................................................................................5 SECTION 3: SITE CONDITIONS....................................................................................................5

3.1 Recent History------------------------------------------------------------------------------------------------ 5

3.2 Surface Description/Geomorphology----------------------------------------------------------------- 6

3.3 Ground Water Investigation------------------------------------------------------------------------------ 6 Table 2: Depth to Ground Water ..............................................................................................7 SECTION 4: GEOLOGIC HAZARDS .............................................................................................8

4.1 Faulting --------------------------------------------------------------------------------------------------------- 8

4.1.1 Proposed Sewer Line ..................................................................................................10

4.2 Fault Surface Rupture-------------------------------------------------------------------------------------10

4.2.1 Previous Consultant’s Studies...................................................................................10

4.2.2 Current Fault Investigation.........................................................................................13

4.2.3 Encountered Geologic Units in Exploratory Trenches ............................................15 SECTION 5: CONCLUSIONS.......................................................................................................17

5.1 Summary ------------------------------------------------------------------------------------------------------17 2064

GIOVANNONI PROPERTY
582-4-1
Page ii

5.2 Mitigating Fault Surface Rupture----------------------------------------------------------------------18 SECTION 6: LIMITATIONS ..........................................................................................................19 SECTION 7: REFERENCES.........................................................................................................20 FIGURE 1: VICINITY MAP
FIGURE 2: SITE EXPLORATION PLAN
FIGURE 3: VICINITY GEOLOGIC MAP
FIGURE 4: REGIONAL FAULT MAP
FIGURE 5: ALQUIST-PRIOLO EARTHQUAKE REGULATORY ZONE MAP FIGURE 6: PREVIOUS INVESTIGATIONS
FIGURE 7: FAULT INVESTIGATION MAP
FIGURE 8A TO 8C: EXPLORATORY TRENCH 1 AND TRENCH 1 DETAIL FIGURES 9A TO 9D: EXPLORATORY TRENCH 2A & 2B
APPENDIX A: SEISMIC DESIGN AND ASSESSMENT GUIDLINES
2065

GIOVANNONI PROPERTY
582-4-1

Page 1 ends

American Canyon City CouncilFebruary 21, 2023

American Canyon City Council
February 21, 2023