Beaumont City Council
October 17, 2023

Clarified Mitigation Monitoring and Reporting Program
Mesa Lift Station and Force Main Project

Clarified MMRP-15
Impact
Category Mitigation Measure
Implementation
Timing
Responsible
Monitoring
Party
Monitoring/
Reporting
Method Compliance Verification
Cultural
Resources
MM CR-5: Inadvertent Discovery of Human
Remains. In the event human remains are
discovered during Project activities, the contractor
and City of Beaumont shall comply with Health and
Safety Code §7050.5 and Public Resource Code
(PRC) §5097.98 which will identify the process of
notification to the Tribes and the appropriate County
Coroner (i.e., Riverside County Corner or San
Bernardino County Corner depending on the
location of the discovery) as well as how the remains
will be treated if they are identified as Native
American. The contractor shall notify the City of
Beaumont Public Works Department in the event
human remains are found and identified as Native
American so that the City Public Works Department
can ensure PRC §5097.98 has been followed.

During
construction.

Contractor,
Beaumont
Public Works
Dept., County
Coroner,
Native
American
Heritage
Commission
Record to the
City of find,
notification to
Tribes and
County Coroner,
and treatment
method.

City to record
compliance with
P.R.C. §5097.98.

Geology and
Soils
MM PALEO-1: Paleontological Resources
Workers Environmental Awareness Program
(WEAP). To educate construction crews about the
types of paleontological resources that may be
encountered at the Lift Station Site and along the
Force Main alignment, prior to the start of the
construction, the City of Beaumont shall retain a
professional paleontologist meeting the standards of
the Society of Vertebrate Paleontology (the “Project
Paleontologist”) to prepare a Paleontological
Resources Workers Environmental Awareness
Program (WEAP). The Paleontological Resources
WEAP shall provide a description of the laws and
ordinances protecting fossil resources, the types of
Prior to
construction
during each
crew’s
preconstruction
meeting.

Project
Paleontologist
Contractor
Evidence to the
City of training
provided.

Clarified Mitigation Monitoring and Reporting Program
Mesa Lift Station and Force Main Project

Clarified MMRP-16
Impact
Category Mitigation Measure
Implementation
Timing
Responsible
Monitoring
Party
Monitoring/
Reporting
Method Compliance Verification
fossil resources that may be encountered in the
area, the role of the paleontological monitor, outline
steps to follow in the event that a fossil discovery is made, and provide contact information for the
Project Paleontologist. The Project Paleontologist or
designee(s) shall present the Paleontological
Resources WEAP to the construction contractor and
each of the construction crews working on the Lift
Station and Force Main Project during a
preconstruction meeting. The Paleontological
Resources WEAP shall be taped and presented to
any construction crew members not present at the
preconstruction meeting during which it was initially
presented prior to working at the Lift Station Site or
along the Force Main Alignment. This training may
be conducted concurrent with other preconstruction
training (e.g., biological resources, cultural
resources, safety).

Geology and
Soils
MM PALEO-2: Paleontological Resources
Mitigation Monitoring Plan (PRMMP). Prior to the
commencement of ground-disturbing activities for
the Force Main, the Project Paleontologist (retained
under MM PALEO-1) shall prepare a
Paleontological Resources Mitigation Monitoring
Plan (PRMMP) for the project. The PRMMP shall
describe the monitoring required during project
excavations and the frequency of monitoring.

Paleontological Monitoring shall entail the visual
inspection of earth-disturbing activities during
construction of the Project. If the Project
Prior to ground
disturbing
activities for the
Force Main
Project
Paleontologist
City staff
Completed
PRMMP
Monitoring report
if monitoring is
required.

Determination to
the City that
monitoring can
be discontinued,
if warranted.

Clarified Mitigation Monitoring and Reporting Program
Mesa Lift Station and Force Main Project

Clarified MMRP-17
Impact
Category Mitigation Measure
Implementation
Timing
Responsible
Monitoring
Party
Monitoring/
Reporting
Method Compliance Verification
Paleontologist determines full-time monitoring is no
longer warranted, based on the geologic conditions
at depth, the Project Paleontologist may recommend
monitoring be reduced or ceased entirely.

Geology and
Soils
MM PALEO-3: In the event that a paleontological
resource is discovered, the Project Paleontologist
shall have the authority to temporarily divert the
construction equipment around the find until it is
assessed for scientific significance and, if
appropriate, collected. If the resource is determined
to be of scientific significance, the Project
Paleontologist shall complete the following:

1. Salvage of Fossils. If fossils are discovered,
all work in the immediate vicinity should be
halted to allow the paleontological monitor,
and/or Project Paleontologist to evaluate the
discovery and determine if the fossil may be
considered significant. If the fossils are
determined to be potentially significant, the
Project Paleontologist (or paleontological
monitor) should recover them following
standard field procedures for collecting
paleontological as outlined in the PRMMP
prepared per mitigation measure
MM PALEO-1.

2. Fossil Preparation and Curation. The
PRMMP shall identify the museum that has
agreed to accept fossils that may be
discovered during project-related
excavations. Upon completion of fieldwork,
During
construction
Project
Paleontologist
Final
paleontological
mitigation and
monitoring report
provided to City.

Clarified Mitigation Monitoring and Reporting Program
Mesa Lift Station and Force Main Project

Clarified MMRP-18
Impact
Category Mitigation Measure
Implementation
Timing
Responsible
Monitoring
Party
Monitoring/
Reporting
Method Compliance Verification
all significant fossils collected shall be
prepared in a properly equipped laboratory
to a point ready for curation. Preparation
may include the removal of excess matrix
from fossil materials and stabilizing or
repairing specimens. During preparation and
inventory, the fossil specimens will be
identified to the lowest taxonomic level
practical prior to curation at an accredited
museum. The fossil specimens must be
delivered to the accredited museum or
repository no later than 90 days after all
fieldwork is completed. The cost of curation
will be assessed by the repository and will
be the responsibility of the City of
Beaumont.

3. Final Paleontological Mitigation Report.

Upon completion of ground disturbing
activity (and curation of fossils if necessary)
for project construction, the Project
Paleontologist shall prepare a final mitigation
and monitoring report outlining the results of
the mitigation and monitoring program. The
report shall include discussion of the
location, duration and methods of the
monitoring, stratigraphic sections, any
recovered fossils, and the scientific
significance of those fossils, and where
fossils were curated

Clarified Mitigation Monitoring and Reporting Program
Mesa Lift Station and Force Main Project

Clarified MMRP-19
Impact
Category Mitigation Measure
Implementation
Timing
Responsible
Monitoring
Party
Monitoring/
Reporting
Method Compliance Verification
Geology and
Soils
MM GEO-1: Geotechnical Investigation. Prior to
approval of the final plans, a site specific
Geotechnical Report(s) for the Project shall be
prepared. Recommendations identified in the site
specific Geotechnical Report(s) shall be
incorporated into the Project design and
construction.

This Beaumont MND mitigation measure is not applicable to the Lift Station and Force Main Project because it has been satisfied by preparation of the Geotechnical Investigation Report for the Mesa Lift Station Upgrades and the Geotechnical Investigation Report for the Brine Disposal Pipeline.

Noise MM NOISE-1. Equipment Maintenance: To
minimize noise impacts resulting from poorly tuned
or improperly modified vehicles and construction
equipment, all vehicles and construction equipment
shall maintain equipment engines and mufflers in
good condition and in proper tune per
manufacturers’ specifications to the satisfaction of
the City of Beaumont Public Works Department.

Equipment maintenance records and equipment
design specification data sheets shall be kept and
maintained by the contractor and available for
review by the City upon request.

Before and
during
construction.

Contractor,
Beaumont
Public Works
Dept.

Submit proof to
the City
construction
equipment is
properly tuned
and unmodified.

Noise MM NOISE-2. Idling Engines: To minimize noise
from idling engines, all vehicles and construction
equipment shall be prohibited from idling in excess
of five (5) minutes when not in use.

During
construction.

Contractor. Submittal of proof
to the City that
this information
has been
provided to all
construction staff.

Clarified Mitigation Monitoring and Reporting Program
Mesa Lift Station and Force Main Project

Clarified MMRP-20
Impact
Category Mitigation Measure
Implementation
Timing
Responsible
Monitoring
Party
Monitoring/
Reporting
Method Compliance Verification
Noise MM NOISE-3. Construction Hours. All
construction activities on the brine pipeline within
the City of Colton, City of San Bernardino, City of
Redlands, City of Calimesa, and City of Beaumont
shall be limited to occur on the days and between
the hours directed by each respective agency.

Beaumont WWTP MND mitigation measure MM NOISE-3 is not applicable to the Lift Station and Force Main Project because no work will be done in the Cities of Colton, San Bernardino, Redlands, or Calimesa.

Traffic and
Transportation
CMM TRANS-1. Traffic Control Plans: Prior to the
initiation of construction activities where a public
roadway will be affected by a lane or segment
closure or modification of a travel lane, a Traffic
Control Plan shall be prepared for such segment and
approved by the City of Beaumont.

Prior to
construction.

Contractor,
Beaumont
Public Works
staff.

Submittal of
approved Traffic
Control Plan.

City of Beaumont
Request for bid

Mesa Lift Station Force Main
CIP WW-09

APPENDICES
2 APPENDIX B – FORCE MAIN ASBUILTS

City of Beaumont
Request for bid

Mesa Lift Station Force Main
CIP WW-09

APPENDICES
3 APPENDIX C – QST IMPACTED PROJECT REQUIREMENTS

Questar Southern Trails
Right of Way and Easement Requirements

Safety is the primary concern during all stages of planning, construction and long-term operation of Questar Southern Trails’ (QST) pipeline and your facility. Therefore, QST requires the following for projects taking place within or near a QST Right of Way or Easement (ROW/E):

1. QST must approve any plans for work to be performed within the ROW/E before construction begins.

2. QST must have continuous uninterrupted access to its easement.

3. No permanent structures are allowed inside the ROW/E unless approved in writing by QST.

4. Fencing may be allowed within the ROW/E if plans are reviewed and approved by QST. If approved, QST will require full access to their ROW/E (gates, etc.) for utility vehicles and construction equipment.

QST will also determine the location of any fence posts or other support structures. Damage to fencing as the result of QST’s access to their ROW/E is the responsibility of the property owner. QST will not be responsible for damage or replacement of fencing within a QST ROW/E.

5. Landscaping is allowed within a QST ROW/E if plans are reviewed and approved by QST. Landscaping items which are not allowed include, but are not limited to, boulders, deep-rooted trees and vegetation and above ground planter boxes since these and similar items may potentially damage the pipeline and impede access to QST’s ROW/E. Damage to landscaping as a result of QST’s access to their ROW/E is the responsibility of the property owner. QST will not be responsible for damage or replacement of landscaping within a QST ROW/E.

6. Water drainage must be designed to prevent erosion within the QST ROW/E.

7. Underground structures and utilities must be spaced at least three horizontal feet and one vertical foot from QST pipe.

8. The depth of cover over the pipeline must be a minimum of three feet and a maximum of six feet unless approved in writing.

9. Equipment working within or crossing the ROW/E must be approved by QST to ensure it does not cause damage to the pipeline. The equipment weight, vehicle wheel/track arrangement, and depth of cover must be provided to QST for analysis and approval. Some vehicles may have to be restricted to specially prepared crossing locations.

10. No mechanical equipment is allowed to operate within three horizontal feet or two vertical feet of the pipeline. Any closer work must be performed by hand.

11. Buried pipelines shall not be left exposed and exposed pipelines shall not be buried without prior inspection and approval.

12. QST personnel must be notified at least two full business days prior to potholing or construction activities within a QST ROW/E so they can arrange to be on site. Please call 801-324-7718 to provide this notification. This is in addition to the Underground Service Alert notification.

13. If a QST inspector determines that there is a threat of imminent danger to the pipeline facilities, the inspector many suspend your activities inside the ROW/E.

QST strongly recommends potholing the pipeline in at least three locations to verify the depth of the pipeline throughout your project area as early as possible to avoid conflicts or damage during the construction phase.

City of Beaumont
Request for bid

Mesa Lift Station Force Main
CIP WW-09

APPENDICES
4 APPENDIX D – APPROVED PLUG VALVES

45 of 56 PAGES
Appendix A
Rev: 6/7/2022

PLUG VALVES

Description Manufacturers

1. Eccentric Fullport Non-Lubricated
Plug Valves
3” thru 24”

DEZURIK
Model: G Series

HENRY PRATT CO.

Pratt Keystone 580 Series, #898

City of Beaumont
Request for bid

Mesa Lift Station Force Main
CIP WW-09

APPENDICES
5 APPENDIX E – POTHOLE REPORTS

Utility Locating
Radiography
Potholing
Mapping
GPR

SUBSURFACE IMAGING
BELOWC
www.cbelow.com
1-888-90-BELOW
14280 Euclid Ave.

Chino, CA 91710
Date: October 21, 2022
Technician: Berny Loaiza
Project Name: City of Beaumont
Project Address: Potrero Blvd. & Western Knolls Ave. Beaumont, CA C Below Project No. 22-4704
Po
t
h
o
l
e

R
e
p
o
r
t

14280 Euclid Ave
Chino, CA 91710
1-888-90-BELOW

SUBSURFACE IMAGING
BELOWC
22-4704 City of Beaumont www.cbelow.com
No. Utility
Size
(in)Material Top Depth
(ft)Direction Location Surface
1 Sewer 16 Plastic 6.96 E-W North Bound on Portelo Blvd. on Shoulder, South of Castello Ln.Soil
2 Reclaimed
Water Unknown Encasement 0.50 N-S
North Bound on Portrero Blvd. on
Shoulder, Approx. 50.00 ft. of Pump
Station
Soil
3 Brine 12 Unknown 4.06 N-S North Bound on Portelo Blvd. on Shoulder, South of Castello Ln.Soil
5 Sewer 12 Plastic 11.12 NE-SW
North bound on Potrero Blvd. on
Shoulder, North of Olivewood Soil
6 Unknown 16 Clay 9.60 N-S North Bound on Potrero Blvd. on Shoulder, South of Olivewood Soil

6.1 Unknown 16 Wrapped 6.90 E-W North Bound on Potrero Blvd. on Shoulder, South of Olivewood Soil
7 Reclaimed
Water 24 Wrapped 4.98 N-S North Bound on Potrero Blvd. on Shoulder, North Western Knolls Ave.Soil
10 Comm 4 Plastic 1.69 E-W
East Bound on Western Knolls
Ave., North of West Bound 60 fwy.

Entrance
Asphalt
19 Unknown Unknown Encasement 2.22 NE-SW
South Bound on Nicholas Road on
Right Turning Lane, North of 4th
Street Intersection
Asphalt
19A Dry Hole N/A N/A N/A N/A
South Bound on Nicholas Road on
Left Turning Lane, North of 4th Street
Intersection
Asphalt
19B Sewer 16 PVC 5.62 N-S
South Bound on Nicholas Road on
Right Turning Lane, North of 4th
Street Intersection
Asphalt
Comments: Top depth is measured from ground surface to top of utility. Potholes were performed at locations specifi ed by the client. Utility size and material are based on visual estimates and may vary. Approximate coordinates (Lat/Long) are provided to show a general area of pothole location and are for information purposes only.

Project Summary
Date: October 21, 2022
Technician: Berny Loaiza
Project Name: City of Beaumont
Project Address: Potrero Blvd. & Western Knolls Ave. Beaumont, CA C Below Project No. 22-4704

14280 Euclid Ave
Chino, CA 91710
1-888-90-BELOW

SUBSURFACE IMAGING
BELOWC
22-4704 City of Beaumont www.cbelow.com
No. Utility
Size
(in)Material Top Depth
(ft)Direction Location Surface
20 Sewer 16 PVC 5.70 N-S South Bound on Nicholas Road,
South West of Address 630 Asphalt
21 Sewer 12 PVC 5.82 N-S South Bound on Nicholas Road,
South West of Address 630 Asphalt
22 Sewer 16 PVC 7.30 N-S South Bound on Nicholas Road,
South West of Address 630 Asphalt
23 Sewer 16 PVC 8.02 E-W
South Bound on Nicholas Road
Behind Sidewalk, West of Address
630
Asphalt
Comments: Top depth is measured from ground surface to top of utility. Potholes were performed at locations specifi ed by the client. Utility size and material are based on visual estimates and may vary. Approximate coordinates (Lat/Long) are provided to show a general area of pothole location and are for information purposes only.

Project Summary
Date: October 21, 2022
Technician: Berny Loaiza
Project Name: City of Beaumont
Project Address: Potrero Blvd. & Western Knolls Ave. Beaumont, CA C Below Project No. 22-4704

Notes:

Top:

Bottom:

Profi le View (not to scale)
Size:

Utility:

Material:

Direction:
(feet)
(feet)
(in)

POTHOLING DATA SHEET
Technician Name Date C Below Project No.

Project Name Project Address
Client Company Contact
14280 EUCLID AVE., CHINO, CA 91710
OFFICE: (888) 902-3569
FAX: (909) 606-6555
Pothole No.Location
Surface Type:

Thickness:

Measured Distance from Finished Surface

PHYSICAL SWING TIE INFORMATION

LOCATION DETAIL
(feet)
www.cbelow.com

SUBSURFACE IMAGINGBELOWC
No. Distance (ft) Dir. From Permanent Existing Fixture No. Distance (ft) Dir. From Permanent Existing Fixture No. Distance (ft) Dir. From Permanent Existing Fixture 1 2 3
Berny Loaiza 09-12-2022 22-4704
City of Beaumont | Mesa Lift Station & Force Main Project Potrero Blvd and Western Knolls Avenue Beaumont, CA Webb Associates Brad Sackett
1 North Bound on Portelo Blvd. on Shoulder, South of Castello Ln.

Soil
N/A

6.96 Unknown
16 Sewer
Plastic
E-W
Approximate Coordinates 33.9401821, -117.0164226

41.90 S Vault 13.80 W Wall 34.90 N Electrical Vault

www.cbelow.com
No. Utility
Size
(in)Material Top Depth
(ft)Direction Location Surface
Comments:

Photo 1 Photo 2
Photo 3 Photo 4
Sewer 16 Plastic 6.961 E-W
North Bound on Portelo Blvd. on Shoulder, South
of Castello Ln.Soil

Notes:

Top:

Bottom:

Profi le View (not to scale)
Size:

Utility:

Material:

Direction:
(feet)
(feet)
(in)

POTHOLING DATA SHEET
Technician Name Date C Below Project No.

Project Name Project Address
Client Company Contact
14280 EUCLID AVE., CHINO, CA 91710
OFFICE: (888) 902-3569
FAX: (909) 606-6555
Pothole No.Location
Surface Type:

Thickness:

Measured Distance from Finished Surface

PHYSICAL SWING TIE INFORMATION

LOCATION DETAIL
(feet)
www.cbelow.com

SUBSURFACE IMAGINGBELOWC
No. Distance (ft) Dir. From Permanent Existing Fixture No. Distance (ft) Dir. From Permanent Existing Fixture No. Distance (ft) Dir. From Permanent Existing Fixture 1 2 3
Matthew Matlock 09-12-2022 22-4704
City of Beaumont | Mesa Lift Potrero Blvd and Western Knolls Avenue Beaumont, CA Webb Associates Brad Sackett
2 North Bound on Portrero Blvd. on Shoulder, Approx. 50.00 ft. of Pump Station Soil
N/A

0.50 Unknown
Unknown
Reclaimed
Water
Encasement
N-S
PH Location based of plans.

Per City water inspector Reclaimed water was encased due to it being shallow.

53.80 E Lane Line 50.30 NW Power Pole 68.70 W Block wall

www.cbelow.com
No. Utility
Size
(in)Material Top Depth
(ft)Direction Location Surface
Comments:

Photo 1 Photo 2
Photo 3 Photo 4
Unknown 0.502 N-S
North Bound on Portrero Blvd. on Shoulder,
Approx. 50.00 ft. of Pump Station SoilEncasementReclaimed Water

Notes:

Top:

Bottom:

Profi le View (not to scale)
Size:

Utility:

Material:

Direction:
(feet)
(feet)
(in)

POTHOLING DATA SHEET
Technician Name Date C Below Project No.

Project Name Project Address
Client Company Contact
14280 EUCLID AVE., CHINO, CA 91710
OFFICE: (888) 902-3569
FAX: (909) 606-6555
Pothole No.Location
Surface Type:

Thickness:

Measured Distance from Finished Surface

PHYSICAL SWING TIE INFORMATION

LOCATION DETAIL
(feet)
www.cbelow.com

SUBSURFACE IMAGINGBELOWC
No. Distance (ft) Dir. From Permanent Existing Fixture No. Distance (ft) Dir. From Permanent Existing Fixture No. Distance (ft) Dir. From Permanent Existing Fixture 1 2 3
Matthew Matlock 09-08-2022 22-4704
City of Beaumont | Mesa Lift Potrero Blvd and Western Knolls Avenue Beaumont, CA Webb Associates Brad Sackett
3 North Bound on Portelo Blvd. on Shoulder, South of Castello Ln.

Soil
N/A

4.06 5.06
12 Brine
Unknown
N-S
Approximate Coordinates 33.940028,-117.016609
Material of line unknown .

Line is a Brine line.

30.20 E Lane line 92.50 W Block wall 54.10 NW Power Pole

www.cbelow.com
No. Utility
Size
(in)Material Top Depth
(ft)Direction Location Surface
Comments:

Photo 1 Photo 2
Photo 3 Photo 4
Brine 12 Unknown 4.063 N-S
North Bound on Portelo Blvd. on Shoulder, South
of Castello Ln.Soil

Notes:

Top:

Bottom:

Profi le View (not to scale)
Size:

Utility:

Material:

Direction:
(feet)
(feet)
(in)

POTHOLING DATA SHEET
Technician Name Date C Below Project No.

Project Name Project Address
Client Company Contact
14280 EUCLID AVE., CHINO, CA 91710
OFFICE: (888) 902-3569
FAX: (909) 606-6555
Pothole No.Location
Surface Type:

Thickness:

Measured Distance from Finished Surface

PHYSICAL SWING TIE INFORMATION

LOCATION DETAIL
(feet)
www.cbelow.com

SUBSURFACE IMAGINGBELOWC
No. Distance (ft) Dir. From Permanent Existing Fixture No. Distance (ft) Dir. From Permanent Existing Fixture No. Distance (ft) Dir. From Permanent Existing Fixture 1 2 3
Berny Loaiza 09-12-2022 22-4704
City of Beaumont | Mesa Lift Station & Force Main Project Potrero Blvd and Western Knolls Avenue Beaumont, CA Webb Associates Brad Sackett
5 North bound on Potrero Blvd. on Shoulder, North of Olivewood Soil
N/A

11.12 12.12
12 Sewer
Plastic
NE-SW
Approximate Coordinates 33.9373694, -117.0167257

22.60 E Edge of Asphalt 19.20 SW Sewer Manhole 49.20 NW Water Valve

www.cbelow.com
No. Utility
Size
(in)Material Top Depth
(ft)Direction Location Surface
Comments:

Photo 1 Photo 2
Photo 3 Photo 4
Sewer 12 Plastic 11.125 NE-SW
North bound on Potrero Blvd. on Shoulder,
North of Olivewood Soil

Notes:

Top:

Bottom:

Profi le View (not to scale)
Size:

Utility:

Material:

Direction:
(feet)
(feet)
(in)

POTHOLING DATA SHEET
Technician Name Date C Below Project No.

Project Name Project Address
Client Company Contact
14280 EUCLID AVE., CHINO, CA 91710
OFFICE: (888) 902-3569
FAX: (909) 606-6555
Pothole No.Location
Surface Type:

Thickness:

Measured Distance from Finished Surface

PHYSICAL SWING TIE INFORMATION

LOCATION DETAIL
(feet)
www.cbelow.com

SUBSURFACE IMAGINGBELOWC
No. Distance (ft) Dir. From Permanent Existing Fixture No. Distance (ft) Dir. From Permanent Existing Fixture No. Distance (ft) Dir. From Permanent Existing Fixture 1 2 3
Matthew Matlock 09-08-2022 22-4704
City of Beaumont | Mesa Lift Potrero Blvd and Western Knolls Avenue Beaumont, CA Webb Associates Brad Sackett
6 North Bound on Potrero Blvd. on Shoulder, South of Olivewood Soil
N/A

9.60 10.90
16 Unknown
Clay
N-S
Approximate Coordinates 33.936110,-117.016421
Standby Rep. from Gas co. was on site.

Did not encounter Gas line at stop Depth of 10.00 ft., undermined 6.00 ft. North and South.

Exposed multiple utilities see pothole 6.1 for additional information.

49.50 NW Stop Ahead Sign 164.70 SW Power Pole 28.70 E Lane line

www.cbelow.com
No. Utility
Size
(in)Material Top Depth
(ft)Direction Location Surface
Comments:

Photo 1 Photo 2
Photo 3 Photo 4
Unknown 16 Clay 9.606 N-S
North Bound on Potrero Blvd. on Shoulder,
South of Olivewood Soil

Notes:

Top:

Bottom:

Profi le View (not to scale)
Size:

Utility:

Material:

Direction:
(feet)
(feet)
(in)

POTHOLING DATA SHEET
Technician Name Date C Below Project No.

Project Name Project Address
Client Company Contact
14280 EUCLID AVE., CHINO, CA 91710
OFFICE: (888) 902-3569
FAX: (909) 606-6555
Pothole No.Location
Surface Type:

Thickness:

Measured Distance from Finished Surface

PHYSICAL SWING TIE INFORMATION

LOCATION DETAIL
(feet)
www.cbelow.com

SUBSURFACE IMAGINGBELOWC
No. Distance (ft) Dir. From Permanent Existing Fixture No. Distance (ft) Dir. From Permanent Existing Fixture No. Distance (ft) Dir. From Permanent Existing Fixture 1 2 3
Matthew Matlock 09-09-2022 22-4704
City of Beaumont | Mesa Lift Potrero Blvd and Western Knolls Avenue Beaumont, CA Webb Associates Brad Sackett

6.1 North Bound on Potrero Blvd. on Shoulder, South of Olivewood Soil
N/A

6.90 8.00
16 Unknown
Wrapped
E-W
Approximate Coordinates 33.936110,-117.016421

51.60 NW Stop Ahead Sign 162.70 SW Power Pole 27.60 E White Lane Line

www.cbelow.com
No. Utility
Size
(in)Material Top Depth
(ft)Direction Location Surface
Comments:

Photo 1 Photo 2
Photo 3 Photo 4
Unknown 16 Wrapped 6.906.1 E-W
North Bound on Potrero Blvd. on Shoulder,
South of Olivewood Soil

Notes:

Top:

Bottom:

Profi le View (not to scale)
Size:

Utility:

Material:

Direction:
(feet)
(feet)
(in)

POTHOLING DATA SHEET
Technician Name Date C Below Project No.

Project Name Project Address
Client Company Contact
14280 EUCLID AVE., CHINO, CA 91710
OFFICE: (888) 902-3569
FAX: (909) 606-6555
Pothole No.Location
Surface Type:

Thickness:

Measured Distance from Finished Surface

PHYSICAL SWING TIE INFORMATION

LOCATION DETAIL
(feet)
www.cbelow.com

SUBSURFACE IMAGINGBELOWC
No. Distance (ft) Dir. From Permanent Existing Fixture No. Distance (ft) Dir. From Permanent Existing Fixture No. Distance (ft) Dir. From Permanent Existing Fixture 1 2 3
Berny Loaiza 09-09-2022 22-4704
City of Beaumont | Mesa Lift Station & Force Main Project Potrero Blvd and Western Knolls Avenue Beaumont, CA Webb Associates Brad Sackett
7 North Bound on Potrero Blvd. on Shoulder, North Western Knolls Ave.

Soil
N/A

4.98 6.98
24 Reclaimed
Water
Wrapped
N-S
Approximate Coordinates 33.9354609, -117.0165936

20.40 SW Power Pole 30.20 NW Vent 26.70 S No Trespassing Sing

www.cbelow.com
No. Utility
Size
(in)Material Top Depth
(ft)Direction Location Surface
Comments:

Photo 1 Photo 2
Photo 3 Photo 4
Reclaimed
Water 24 Wrapped 4.987 N-S
North Bound on Potrero Blvd. on Shoulder,
North Western Knolls Ave.Soil

Notes:

Top:

Bottom:

Profi le View (not to scale)
Size:

Utility:

Material:

Direction:
(feet)
(feet)
(in)

POTHOLING DATA SHEET
Technician Name Date C Below Project No.

Project Name Project Address
Client Company Contact
14280 EUCLID AVE., CHINO, CA 91710
OFFICE: (888) 902-3569
FAX: (909) 606-6555
Pothole No.Location
Surface Type:

Thickness:

Measured Distance from Finished Surface

PHYSICAL SWING TIE INFORMATION

LOCATION DETAIL
(feet)
www.cbelow.com

SUBSURFACE IMAGINGBELOWC
No. Distance (ft) Dir. From Permanent Existing Fixture No. Distance (ft) Dir. From Permanent Existing Fixture No. Distance (ft) Dir. From Permanent Existing Fixture 1 2 3
Berny Loaiza 09-09-2022 22-4704
City of Beaumont | Mesa Lift Station & Force Main Project Potrero Blvd and Western Knolls Avenue Beaumont, CA Webb Associates Brad Sackett
10 East Bound on Western Knolls Ave., North of West Bound 60 fwy. Entrance Asphalt

0.50 1.69
Unknown
4 Comm
Plastic
E-W
Approximate Coordinates 33.9339641, -117.0082080

32.30 SW Street Sing 17.70 S Edge of Asphalt 55.10 NE Stop Sing

www.cbelow.com
No. Utility
Size
(in)Material Top Depth
(ft)Direction Location Surface
Comments:

Photo 1 Photo 2
Photo 3 Photo 4
Comm 4 Plastic 1.6910 E-W
East Bound on Western Knolls Ave., North of
West Bound 60 fwy. Entrance Asphalt

Notes:

Top:

Bottom:

Profi le View (not to scale)
Size:

Utility:

Material:

Direction:
(feet)
(feet)
(in)

POTHOLING DATA SHEET
Technician Name Date C Below Project No.

Project Name Project Address
Client Company Contact
14280 EUCLID AVE., CHINO, CA 91710
OFFICE: (888) 902-3569
FAX: (909) 606-6555
Pothole No.Location
Surface Type:

Thickness:

Measured Distance from Finished Surface

PHYSICAL SWING TIE INFORMATION

LOCATION DETAIL
(feet)
www.cbelow.com

SUBSURFACE IMAGINGBELOWC
No. Distance (ft) Dir. From Permanent Existing Fixture No. Distance (ft) Dir. From Permanent Existing Fixture No. Distance (ft) Dir. From Permanent Existing Fixture 1 2 3
Abraham Padilla 09-24-2022 22-4704
City of Beaumont | Mesa Lift Station & Force Main Project Potrero Blvd and Western Knolls Avenue Beaumont, CA Webb Associates Brad Sackett
19 South Bound on Nicholas Road on Right Turning Lane, North of 4th Street Intersection Asphalt

0.50 2.22

3.92 Unknown
Unknown
Encasement
NE-SW
Potholed on client indicated location.

Exposed a large concrete encasement, unable to verify other edge due to its size.

Encountered a large concrete slab underneath encasement, undermined to sides no edges were encountered.

Approximate Coordinates: 33.9265477, -116.9946571

38.30 NE Sign 13.70 NW Water Valve 59.20 SE Fire Hydrant

www.cbelow.com
No. Utility
Size
(in)Material Top Depth
(ft)Direction Location Surface
Comments:

Photo 1 Photo 2
Photo 3 Photo 4
Unknown Unknown Encasement 2.2219 NE-SW
South Bound on Nicholas Road on Right Turning
Lane, North of 4th Street Intersection Asphalt

ZZZFEHORZFRP
No. Utility
Size
(in)Material Top Depth
(ft)Direction Location Surface
&RPPHQWV

3KRWR 3KRWR
3KRWR3KRWR
Unknown Unknown Encasement 2.2219 NE-SW
South Bound on Nicholas Road on Right Turning
Lane, North of 4th Street Intersection Asphalt

Notes:

Top:

Bottom:

Profi le View (not to scale)
Size:

Utility:

Material:

Direction:
(feet)
(feet)
(in)

POTHOLING DATA SHEET
Technician Name Date C Below Project No.

Project Name Project Address
Client Company Contact
14280 EUCLID AVE., CHINO, CA 91710
OFFICE: (888) 902-3569
FAX: (909) 606-6555
Pothole No.Location
Surface Type:

Thickness:

Measured Distance from Finished Surface

PHYSICAL SWING TIE INFORMATION

LOCATION DETAIL
(feet)
www.cbelow.com

SUBSURFACE IMAGINGBELOWC
No. Distance (ft) Dir. From Permanent Existing Fixture No. Distance (ft) Dir. From Permanent Existing Fixture No. Distance (ft) Dir. From Permanent Existing Fixture 1 2 3
Abraham Padilla 09-24-2022 22-4704
City of Beaumont | Mesa Lift Station & Force Main Project Potrero Blvd and Western Knolls Avenue Beaumont, CA Webb Associates Brad Sackett
19A South Bound on Nicholas Road on Left Turning Lane, North of 4th Street Intersection Asphalt

0.50 N/A

9.22 N/A
Dry Hole
N/A
N/A
No utilities found at pothole location.

Pothole performed on client indicated locations.

Cleared 9.00 ft. and undermined 1.50 ft. to the East.

Per onsite contact was instructed to stopped excavation at obtained depth.

64.50 SE Fire Hydrant 46.00 NE Sign 15.00 NE Water Valve

www.cbelow.com
No. Utility
Size
(in)Material Top Depth
(ft)Direction Location Surface
Comments:

Photo 1 Photo 2
Photo 3 Photo 4
Dry Hole N/A N/A N/A19A N/A
South Bound on Nicholas Road on Left Turning
Lane, North of 4th Street Intersection Asphalt

Notes:

Top:

Bottom:

Profi le View (not to scale)
Size:

Utility:

Material:

Direction:
(feet)
(feet)
(in)

POTHOLING DATA SHEET
Technician Name Date C Below Project No.

Project Name Project Address
Client Company Contact
14280 EUCLID AVE., CHINO, CA 91710
OFFICE: (888) 902-3569
FAX: (909) 606-6555
Pothole No.Location
Surface Type:

Thickness:

Measured Distance from Finished Surface

PHYSICAL SWING TIE INFORMATION

LOCATION DETAIL
(feet)
www.cbelow.com

SUBSURFACE IMAGINGBELOWC
No. Distance (ft) Dir. From Permanent Existing Fixture No. Distance (ft) Dir. From Permanent Existing Fixture No. Distance (ft) Dir. From Permanent Existing Fixture 1 2 3
Abraham Padilla 09-24-2022 22-4704
City of Beaumont | Mesa Lift Station & Force Main Project Potrero Blvd and Western Knolls Avenue Beaumont, CA Webb Associates Brad Sackett
19B South Bound on Nicholas Road on Right Turning Lane, North of 4th Street Intersection Asphalt

0.50 5.62

6.95 16
Sewer
PVC
N-S
Pothole performed on client indicated locations.

Exposed a large PVC line, sewer line per client's information.

52.00 SE Fire Hydrant 44.20 NE Sign 21.30 NW Water Valve

www.cbelow.com
No. Utility
Size
(in)Material Top Depth
(ft)Direction Location Surface
Comments:

Photo 1 Photo 2
Photo 3 Photo 4
Sewer 16 PVC 5.6219B N-S
South Bound on Nicholas Road on Right Turning
Lane, North of 4th Street Intersection Asphalt

Notes:

Top:

Bottom:

Profi le View (not to scale)
Size:

Utility:

Material:

Direction:
(feet)
(feet)
(in)

POTHOLING DATA SHEET
Technician Name Date C Below Project No.

Project Name Project Address
Client Company Contact
14280 EUCLID AVE., CHINO, CA 91710
OFFICE: (888) 902-3569
FAX: (909) 606-6555
Pothole No.Location
Surface Type:

Thickness:

Measured Distance from Finished Surface

PHYSICAL SWING TIE INFORMATION

LOCATION DETAIL
(feet)
www.cbelow.com

SUBSURFACE IMAGINGBELOWC
No. Distance (ft) Dir. From Permanent Existing Fixture No. Distance (ft) Dir. From Permanent Existing Fixture No. Distance (ft) Dir. From Permanent Existing Fixture 1 2 3
Abraham Padilla 10-21-2022 22-4704
City of Beaumont | Mesa Lift Station & Force Main Project Potrero Blvd and Western Knolls Avenue Beaumont, CA 92223 Webb Associates Brad Sackett
20 South Bound on Nicholas Road, South West of Address 630 Asphalt

0.50 5.70

7.03 16
Sewer
PVC
N-S
Potholed on client's staked location.

Exposed a large line, client was looking for a capped end.

Undermined to follow line 2.00 ft. unable to expose end.

Approximate Coordinates: 33.9289769, -116.9946400

37.10 NE Water Riser 18.40 NW SD Manhole 16.60 E Face Of Curb

www.cbelow.com
No. Utility
Size
(in)Material Top Depth
(ft)Direction Location Surface
Comments:

Photo 1 Photo 2
Photo 3 Photo 4
Sewer 16 PVC 5.7020 N-S
South Bound on Nicholas Road, South West of
Address 630 Asphalt

Notes:

Top:

Bottom:

Profi le View (not to scale)
Size:

Utility:

Material:

Direction:
(feet)
(feet)
(in)

POTHOLING DATA SHEET
Technician Name Date C Below Project No.

Project Name Project Address
Client Company Contact
14280 EUCLID AVE., CHINO, CA 91710
OFFICE: (888) 902-3569
FAX: (909) 606-6555
Pothole No.Location
Surface Type:

Thickness:

Measured Distance from Finished Surface

PHYSICAL SWING TIE INFORMATION

LOCATION DETAIL
(feet)
www.cbelow.com

SUBSURFACE IMAGINGBELOWC
No. Distance (ft) Dir. From Permanent Existing Fixture No. Distance (ft) Dir. From Permanent Existing Fixture No. Distance (ft) Dir. From Permanent Existing Fixture 1 2 3
Abraham Padilla 10-21-2022 22-4704
City of Beaumont | Mesa Lift Station & Force Main Project Potrero Blvd and Western Knolls Avenue Beaumont, CA 92223 Webb Associates Brad Sackett
21 South Bound on Nicholas Road, South West of Address 630 Asphalt

0.50 5.82

6.82 12
Sewer
PVC
N-S
Exposed forced main sewer.

Approximate Coordinates: 33.9289769, -116.9946400

38.80 NE Water Riser 16.40 NW SD Manhole 19.30 E Face Of Curb

www.cbelow.com
No. Utility
Size
(in)Material Top Depth
(ft)Direction Location Surface
Comments:

Photo 1 Photo 2
Photo 3 Photo 4
Sewer 12 PVC 5.8221 N-S
South Bound on Nicholas Road, South West of
Address 630 Asphalt

Notes:

Top:

Bottom:

Profi le View (not to scale)
Size:

Utility:

Material:

Direction:
(feet)
(feet)
(in)

POTHOLING DATA SHEET
Technician Name Date C Below Project No.

Project Name Project Address
Client Company Contact
14280 EUCLID AVE., CHINO, CA 91710
OFFICE: (888) 902-3569
FAX: (909) 606-6555
Pothole No.Location
Surface Type:

Thickness:

Measured Distance from Finished Surface

PHYSICAL SWING TIE INFORMATION

LOCATION DETAIL
(feet)
www.cbelow.com

SUBSURFACE IMAGINGBELOWC
No. Distance (ft) Dir. From Permanent Existing Fixture No. Distance (ft) Dir. From Permanent Existing Fixture No. Distance (ft) Dir. From Permanent Existing Fixture 1 2 3
Abraham Padilla 10-21-2022 22-4704
City of Beaumont | Mesa Lift Station & Force Main Project Potrero Blvd and Western Knolls Avenue Beaumont, CA 92223 Webb Associates Brad Sackett
22 South Bound on Nicholas Road, South West of Address 630 Asphalt

0.20 7.30

8.63 16
Sewer
PVC
N-S
Encountered 4 inches if concrete underneath asphalt.

Exposed line on client indicated location, line continues.

Approximate Coordinates: 33.9297869, -116.9946470

77.30 W Sign 76.00 SW Street Light 56.00 NE Fire Hydrant

www.cbelow.com
No. Utility
Size
(in)Material Top Depth
(ft)Direction Location Surface
Comments:

Photo 1 Photo 2
Photo 3 Photo 4
Sewer 16 PVC 7.3022 N-S
South Bound on Nicholas Road, South West of
Address 630 Asphalt

Notes:

Top:

Bottom:

Profi le View (not to scale)
Size:

Utility:

Material:

Direction:
(feet)
(feet)
(in)

POTHOLING DATA SHEET
Technician Name Date C Below Project No.

Project Name Project Address
Client Company Contact
14280 EUCLID AVE., CHINO, CA 91710
OFFICE: (888) 902-3569
FAX: (909) 606-6555
Pothole No.Location
Surface Type:

Thickness:

Measured Distance from Finished Surface

PHYSICAL SWING TIE INFORMATION

LOCATION DETAIL
(feet)
www.cbelow.com

SUBSURFACE IMAGINGBELOWC
No. Distance (ft) Dir. From Permanent Existing Fixture No. Distance (ft) Dir. From Permanent Existing Fixture No. Distance (ft) Dir. From Permanent Existing Fixture 1 2 3
Abraham Padilla 10-21-2022 22-4704
City of Beaumont | Mesa Lift Station & Force Main Project Potrero Blvd and Western Knolls Avenue Beaumont, CA 92223 Webb Associates Brad Sackett
23 South Bound on Nicholas Road Behind Sidewalk, West of Address 630 Soil
N/A

8.02 9.35
16 Sewer
PVC
E-W
Potholed on client indicated locations.

Cleared 9.00 ft. and undermined 2.50 ft. to each side.

Exposed line 2.00 ft. North of staked out pothole location.

8.70 NW Gas Valve 6.30 W Face Of Curb N

www.cbelow.com
No. Utility
Size
(in)Material Top Depth
(ft)Direction Location Surface
Comments:

Photo 1 Photo 2
Photo 3 Photo 4
Sewer 16 PVC 8.0223 E-W
South Bound on Nicholas Road Behind Sidewalk,
West of Address 630 Soil

Lead Technician Name Date C Below Project No.

Additional Tech(s)
Project Name Project Address
Client Contact
Service Type
Work Summary - Area Dimensions, Surface Conditions, Subsurface Indications Found, Marking Method, Unlocatable Facilities, Etc.

BELOWSUBSURFACE IMAGING

TECHNICIAN DAILY WORK FORM
14280 EUCLID AVE. CHINO, CA 91710
Office: (888) 90-BELOW
Fax: (909) 606-6555
Ground Penetrating Radar
Utility Locating
CCTV
Utility Locating/GPR
Potholing
Other______________________________

CAUTION
WHEN EXCAVATING WITHIN THE TOLERANCE ZONE (24 INCHES ON EACH SIDE), PERFORM EXCAVATION WITH HAND TOOLS UNTIL THE MARKED FACILITY IS EXPOSED.

FOR CONCRETE AND MASONRY STRUCTURES, DO NOT CUT, CORE OR DRILL WITHIN 3 INCHES OF ANY MARKED INDICATION.

Investigation results provided by C Below, Inc. (CBI), are given in good faith and to the best of our knowledge. However, in the unlikely event that such information proves to be inaccurate, the extent of liability assumed by CBI if any, is limited to the amount billed for labor and materials on the day that the information was provided and alleged to have been inaccurate. The services being provided by CBI do not relieve the Client and/or property owner of the responsibility of having to comply with California Government Code §§4216-4216.9. It is expressly understood by the Client and/or owner that CBI’s services are not a substitute for compliance with the California Code §§4216-4216.9. This daily is based on observations made during a walk-through investigation of the property and is not intended to create any sort of warranty and/or certification that the work performed by the contractor and/or subcontractors was completed in compliance with the governing building codes, architectural plans and specifications or contract documents.

Please Note: Certain low-density material such as PVC and plastic conduit may not be located accurately, if at all, using any investigation method. Always use caution when excavating.

TIME IN TIME OUT REG. HOURS O.T. HOURS TRAVEL TIME
Approved By: ______________________________________________________ Project Contact
_________________________________________________________ Lead Technician Signature
www.cbelow.com
FORM CB-20008 (4/11/2019)
6:45 AM 4
*Performed Potholing operations in search of underground utilities as specified by client. *Performed trenching in search of 16" force main sewer.

Encountered hard soil with rocks
Exposed 12" lines and had large amount of gravel cave ins. Trenched South of 12" exposing 16" line. Due to gravel cave ins hole became large at bottom.

Equipment: Rig 11, unit 44
Surface: soil
Utilities: Sewer
0 4

2.5 Eric Porkert Phone: (310) 382-5121
20-2491Abraham Padilla
Potrero Blvd & Western Knolls Avenue Beaumont, CA 92223 Cannon Corp. | Los Angeles
Berny Loaiza
City of Beaumont | Force main Utility Locating and Mapping Investigation 11:00 AM
10-10-2020

TECHNICIAN DAILY WORK PHOTOS
14280 EUCLID AVE, CHINO, CA 91710
Office: (888) 90-BELOW
Fax: (909) 606-6555
FORM CB-20008 (4/11/2019)

BELOWSUBSURFACE IMAGING
www.cbelow.com
PHOTO 1 PHOTO 2
PHOTO 3 PHOTO 4
Date C Below Project No.
20-249110-10-2020

È6"
##"ı È6"
##"ı
È6"
##"ı
12/12
12 12
12/16
24 12/30
1 2
1 0/1
2 10/12
È
È
È
È
È
È
È
².

È
È
Nicholas Rd
4Th St
Distribu
tion Way
Ri
s
c
o

C
i
r
8 8
12 15Industrial Park
Lift Station
Prosperity Way
12 12
12/16
12/16
30 66 66 2 4/3 0
È
È
Beaumont Mesa
Lift Station
Marshall Creek
Lift Station
8 88
30 8 8
1 2/1
2 12
12 12
È
1 2
§¨¦10
UV60
È
È
È
O li v e w o o d W a y
Potrero Blvd
WWTP
Western Knolls AveÈ
12/16
12/16
12/14
!(
!(
Wastewater Master Plan
City of Beaumont
Exhibit 1
Beaumont Mesa Force Main
Verification
Legend
Existing Sanitary Sewer System
È6"
##"ı Lift Station
16-inch Location Confirmed
Gravity Mains
Force Mains
Parallel Force Main
(To be Verified)
Street Centerlines
Parcels
File Path: P:\xGIS\GIS_Projects\Beaumont\Sewer\191114-WastewaterMP\Verification\BeaumontMesa_FM\BEA_Ex1_BMLS_FM_Confirmation_101220.mxd 5GIS
Updated: June 19, 2020
0 500 1,000250
Feet

PRELIMINARY
!(

City of Beaumont
Request for bid

Mesa Lift Station Force Main
CIP WW-09

APPENDICES
6 APPENDIX F – VARIOUS STANDARD DRAWINGS

08/11/2021Page 1093 of 1492

”
08/11/2021Page 1094 of 1492

08/11/2021Page 1095 of 1492

City of Beaumont
Request for bid

Mesa Lift Station Force Main
CIP WW-09

APPENDICES
7 APPENDIX G – PRESSURE TESTING SCOPE

City of Beaumont Existing 16-in PVC Force Main
Pressure Testing

Pressure Testing Scope:
1) Sta. 77+10+00 +/- on Western Knolls Ave: start of 16-in FM – existing stakes mark this point, to excavate and find 16-in FM, continuous pipe through this section, set up testing location here, need to cut into pipe and block to west and test to east. 2) STA 103+00 +/- at the north end of Nicholas Road – previous excavation at this point found the end of the existing pipe, and already set up pressure test point for testing back to the west. Fill line from this end from available water, need a temp construction meter from BCVWD.
3) Test between section between STA 85+00 and STA 103+00 a. City inspector to be present for testing.
b. Test pressure to be 40 PSI at STA 103+00 (pressure at STA 85+00 will be about 8-10 PSI higher.) Test to last 4 hours. Report pressure at end of test and amount of water required to bring back up to pressure.
c. Provide testing documentation.

Low Pressure Testing Scope:
1) STA 103+50 +/- find end of line and block end of line for low pressure testing. 2) STA 118+00 – at existing manhole at 4th/Nicholas intersection cut and remove existing 16-in FM and plug for testing. If manhole is still active, block 16-in pipe in manhole to prevent flow from other force main discharges from leaking out of this point. 3) Test a low pressure / static pressure test from STA 103+50 to STA 118+00 (this happens to be an almost gravity section at the discharge end of the force main, so low pressures anticipated)
a. City inspector to be present for testing.
b. Test pressure to be 20 PSI at STA 103+50 (pressure at STA 118+00 will be about 4-5 psi higher.) Test to last 4 hours. Report pressure at end of test and amount of water required to bring back up to pressure.
c. Provide testing documentation.

See reference plans attached.

16-IN PVC PIPELINE TO BE PRESSURE TESTED
APPROX. 2,450 FEET OF PIPELINE, SEE ATTACHED.

CITY OF BEAUMONT
Set up fill/test location
near Station 77+00
Set pressure test point near
Station 103+00 (need temp
Const. Meter from BCVWD)

LOW PRESSURE TESTING

NO TESTING

THIS SEGMENT,
VIDEO

INSPECTION
ONLY

Notes:

Find the 16-in pipe, cut the pipe add, in a test port for testing to the east and south only, block the end of the pipe going to the west. (The existing pipe to the west will not be tested.)

NO TESTING

THIS SEGMENT,
VIDEO

INSPECTION
ONLY

PERFORM PRESSURE TESTING FOR GREEEN

SEGMENT OF THE EXISTING PIPELINE
(APPROXIMATELY 2,450 LF OF PIPELINE TO BE
TESTED TO THE SOUTH.)

PERFORM PRESSURE TESTING FOR GREEEN

SEGMENT OF THE EXISTING PIPELINE
(APPROXIMATELY 2,450 LF OF PIPELINE TO BE
TESTED.)

LOW PRESSURE TESTING THIS
SEGMENT TO MH ON 4TH ST
Notes:

The 16-in pipe has been found here, and a test
port has been installed here. Fill pipeline from
this end with existing available water. Use water
from temporary construction meter obtained
from BCVWD. Photos to the left show the test
port installation. Aerial on the right shows the
existing conditions in the area after Nicholas
Street Improvements

PERFORM PRESSURE TESTING FOR GREEEN

SEGMENT OF THE EXISTING PIPELINE
(APPROXIMATELY 2,450 LF OF PIPELINE TO BE
TESTED.)

INSTALL PLUG IN MANHOLE,

SET UP LOW PRESSURE

TESTING FOR LINE ALONG

NICHOLAS

LOW PRESSURE TESTING THIS
SEGMENT TO MH ON 4TH ST

LOCATION OF VALVE VAULT,

NICHOLAS HAS BEEN

IMPROVED SINCE THESE PLANS
WERE PREPARED.

City of Beaumont
Request for bid

Mesa Lift Station Force Main
CIP WW-09

APPENDICES
8 APPENDIX H – FORCE MAIN BYPASS EXHIBIT

City of Beaumont
Request for bid

Mesa Lift Station Force Main
CIP WW-09

APPENDICES
9 APPENDIX I – GEOTECHNICAL REPORTS

GEOTECHNICAL INVESTIGATION REPORT

MESA LIFT STATION UPGRADES
Southeast Corner of the Intersection of Potrero Boulevard and Castello Lane City of Beaumont, Riverside County, California

CONVERSE PROJECT NO. 21-81-289-01
Prepared For: ALBERT A. WEBB ASSOCIATES
3788 McCray Street
Riverside, CA 92506

Presented By: CONVERSE CONSULTANTS
2021 Rancho Drive, Suite 1
Redlands, CA 92373
909-796-0544
June 23, 2022

Converse Consultants
Geotechnical Engineering, Environmental & Groundwater Science, Inspection & Testing Services

2021 Rancho Drive, Suite 1, Redlands, CA 92373
Telephone: (909) 796-0544 ♦ Facsimile: (909) 796-7675 ♦ www.converseconsultants.com

June 23, 2022

Mr. Bradley Sackett, PE
Senior Engineer
Albert A. Webb Associates
3788 McCray Street
Riverside, CA 92506

Subject: GEOTECHNICAL INVESTIGATION REPORT
Mesa Lift Station Upgrades
Southeast Corner of the Intersection of Potrero Boulevard and Castello Lane City of Beaumont, Riverside County, California
Converse Project No. 21-81-289-01

Dear Mr. Sackett:

Converse Consultants (Converse) is pleased to submit this geotechnical investigation report to assist with the design and construction of the Mesa Lift Station upgrades located at the southeast corner of the intersection of Potrero Boulevard and Castello Lane in the City of Beaumont, Riverside County, California. This report was prepared in accordance with our proposal dated December 13, 2021, and your Subconsultant Agreement dated March 8, 2022.

Based upon our field investigation, laboratory data, and analyses, the proposed project is considered feasible from a geotechnical standpoint, provided the recommendations presented in this report are incorporated into the design and construction of the project.

We appreciate the opportunity to be of service to Albert A. Webb Associates. Should you have any questions, please do not hesitate to contact us at 909-796-0544.

CONVERSE CONSULTANTS
Hashmi S. E. Quazi, PhD, PE, GE
Principal Engineer

Dist.: 4/Addressee
HSQ/MS/kvg

Geotechnical Investigation Report
Mesa Lift Station Upgrades
Southeast Corner of the Intersection of Potrero Boulevard and Castello Lane City of Beaumont, Riverside County, California
June 23, 2022
Page ii

Converse Consultants
M:\JOBFILE\2021\81\21-81-289 Webb, Mesa Lift Station & Force Main\Report\21-81-131_GIR(01)booste

PROFESSIONAL CERTIFICATION

This report has been prepared by the following professionals whose seals and signatures appear herein.

The findings, recommendations, specifications and professional opinions contained in this report were prepared in accordance with the generally accepted professional engineering and engineering geologic principle and practice in this area of Southern California. We make no other warranty, either expressed or implied.

Mahmoud Suliman, MS Robert L. Gregorek II, PG, CEG
Staff Engineer Senior Geologist

Hashmi S. E. Quazi, PhD, PE, GE
Principal Engineer

Geotechnical Investigation Report
Mesa Lift Station Upgrades
Southeast Corner of the Intersection of Potrero Boulevard and Castello Lane City of Beaumont, Riverside County, California
June 23, 2022
Page iii

Converse Consultants
M:\JOBFILE\2021\81\21-81-289 Webb, Mesa Lift Station & Force Main\Report\21-81-131_GIR(01)booste

TABLE OF CONTENTS

1.0 INTRODUCTION ---------------------------------------------------------------------------------- 1

2.0 PROJECT DESCRIPTION --------------------------------------------------------------------- 1

3.0 SITE DESCRIPTION ----------------------------------------------------------------------------- 1

4.0 SCOPE OF WORK ------------------------------------------------------------------------------- 2

4.1 Document Review ----------------------------------------------------------------------- 2

4.2 Project Set-up ----------------------------------------------------------------------------- 2

4.3 Subsurface Exploration ----------------------------------------------------------------- 3

4.4 Laboratory Testing ----------------------------------------------------------------------- 3

4.5 Analysis and Report Preparation ----------------------------------------------------- 3

5.0 LABORATORY TEST RESULTS ------------------------------------------------------------ 3

5.1 Physical Testing ------------------------------------------------------------------------- 3

5.2 Chemical Testing - Corrosivity Evaluation ----------------------------------------- 5

6.0 SITE CONDITIONS ------------------------------------------------------------------------------ 5

6.1 Subsurface Profile ----------------------------------------------------------------------- 5

6.2 Groundwater ------------------------------------------------------------------------------ 5

6.3 Expansive Soils --------------------------------------------------------------------------- 6

6.4 Collapse Potential ------------------------------------------------------------------------ 6

6.5 Excavatability ----------------------------------------------------------------------------- 7

6.6 Subsurface Variations ------------------------------------------------------------------ 8

7.0 ENGINEERING GEOLOGY -------------------------------------------------------------------- 8

7.1 Regional Geology ------------------------------------------------------------------------ 8

7.2 Local Geology ----------------------------------------------------------------------------- 8

8.0 FAULTING AND SEISMICITY----------------------------------------------------------------- 8

8.1 Faulting ------------------------------------------------------------------------------------- 9

8.2 CBC Seismic Design Parameters -------------------------------------------------- 10

8.3 Secondary Effects of Seismic Activity --------------------------------------------- 11

9.0 EARTHWORK RECOMMENDATIONS --------------------------------------------------- 12

9.1 General ----------------------------------------------------------------------------------- 12

9.2 Remedial Grading ---------------------------------------------------------------------- 13

9.3 Structural/Engineered Fill ------------------------------------------------------------ 14

9.4 Compacted Fill Placement ----------------------------------------------------------- 14

9.5 Backfill Recommendations Behind Subterranean Wall ---------------------- 15

9.6 Shrinkage and Subsidence --------------------------------------------------------- 15

9.7 Site Drainage ---------------------------------------------------------------------------- 16

9.8 Utility Trench Backfill ------------------------------------------------------------------ 16

Geotechnical Investigation Report
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Southeast Corner of the Intersection of Potrero Boulevard and Castello Lane City of Beaumont, Riverside County, California
June 23, 2022
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10.0 DESIGN RECOMMENDATIONS ---------------------------------------------------------- 19

10.1 Shallow Foundation Design Parameters ----------------------------------------- 19

10.2 Mat Foundation Design Parameters ----------------------------------------------- 19

10.3 Soil Parameters for Pipe Design --------------------------------------------------- 20

10.4 Bearing Pressure for Anchor and Thrust Blocks ------------------------------- 21

10.5 Lateral Earth Pressures and Resistance to Lateral Loads ------------------- 21

10.6 Settlement ------------------------------------------------------------------------------- 22

10.7 Soil Corrosivity -------------------------------------------------------------------------- 22

10.8 Asphalt Concrete Pavement --------------------------------------------------------- 23

11.0 CONSTRUCTION RECOMMENDATIONS ----------------------------------------------- 24

11.1 General ----------------------------------------------------------------------------------- 24

11.2 Temporary Sloped Excavations ---------------------------------------------------- 25

11.3 Shoring Design ------------------------------------------------------------------------- 26

12.0 GEOTECHNICAL SERVICES DURING CONSTRUCTION ------------------------- 28

13.0 CLOSURE ---------------------------------------------------------------------------------------- 29

14.0 REFERENCES ---------------------------------------------------------------------------------- 30

FIGURES
Following Page No.

Figure No. 1, Approximate Project Location Map ................................................................. 1 Figure No. 2, Approximate Boring Locations Map ........................................................... 3 Figure No. 3, Lateral Earth Pressures for Temporary Braced Excavation ..................... 27 Figure No. 3, Lateral Earth Pressures on Temporary Cantilever Wall ........................... 27 TABLES
Page No.

Table No. 1, Summary of USGS Groundwater Depth Data ................................................ 6 Table No. 2, Collapse Potential Values ................................................................................ 7 Table No. 3, Summary of Regional Faults ........................................................................... 9 Table No. 4, CBC Seismic Design Parameters ................................................................. 10 Table No. 5, Overexcavation Depths .................................................................................. 13 Table No. 6, Recommended Foundation Parameters ....................................................... 19 Table No. 7, Soil Parameters for Pipe Design ................................................................... 20 Table No. 8, Active and At-Rest Earth Pressures.............................................................. 21 Table No. 9, Correlation Between Resistivity and Corrosion ............................................ 23 Table No. 10, Recommended Pavement Sections ............................................................ 24 Table No. 11, Slope Ratios for Temporary Excavations ................................................... 25 Table No. 12, Lateral Earth Pressures for Temporary Shoring ........................................ 26

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Southeast Corner of the Intersection of Potrero Boulevard and Castello Lane City of Beaumont, Riverside County, California
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APPENDICES
Appendix A .............................................................................................. Field Exploration Appendix B ............................................................................ Laboratory Testing Program Appendix C ................................................. Liquefaction and Seismic Settlement Analysis

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1.0 INTRODUCTION

This report presents the results of our geotechnical investigation performed for the Mesa Lift Station Upgrades located at the southeast corner of the intersection of Potrero Boulevard and Castello Lane in the City of Beaumont, Riverside County, California. The project location is shown in Figure No. 1, Approximate Project Location Map.

The purposes of this investigation were to determine the nature and engineering properties of the subsurface soils, and to provide design and construction recommendations for the project.

This report is prepared for the project described herein and is intended for use solely by Albert A. Webb Associates and their authorized agents for design purposes. It should not be used as a bidding document but may be made available to the potential contractors for information on factual data only. For bidding purposes, the contractors should be responsible for making their own interpretation of the data contained in this report.

2.0 PROJECT DESCRIPTION

The project will consist of the following.

 Construction of a new 250,000-gallon emergency storage. The approximate dimensions of the emergency storage are 70 to 90 feet wide and 90 feet long, with a maximum depth of 10 feet below surface to allow gravity flow back into the wet well when pumping capacity is restored. The final configuration of the emergency storage was not confirmed at the time of issuing this report.  New pump configuration (4 pumps) to replace the existing pump configuration for increased pumping capacity.
 new VFDs, flow meters, driveway paving, and site improvements

3.0 SITE DESCRIPTION

The Mesa Lift Station site is located at the southeast corner of the intersection of Potrero Boulevard and Castello Lane in the City of Beaumont, Riverside County, California. The station is bounded on the north by Little San Gorgonio Creek, the east and south by an uprising slope and from the west by Potrero Boulevard. The site is surrounded with standard masonry wall on all sides with a gated entrance from the south. The site is covered with around 3 inches of gravel layer. The site has existing pump, odor control and electrical equipment. Photograph No. 1 depict the present site conditions.

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Project No.

Figure No.
20-81-289-01
Project:Mesa Lift Station Upgrades
Southeast Corner of the intersection of Potrero Blvd. & Castello Ln.

City of Beaumont, Riverside County, California
Location:

For:
1 Approximate Project Location Map
Albert Webb Associates
Approximate Project Location
(Not to Scale)
Castello Ln
Po
t
r
e
r
o

B
l
v
d

Geotechnical Investigation Report
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Photograph No. 1: Present site conditions, facing southeast

4.0 SCOPE OF WORK

The scope of this investigation included project set-up, subsurface exploration, laboratory testing, engineering analysis, and preparation of this report, as described in the following sections.

4.1 Document Review

We reviewed geologic maps, aerial photographs, groundwater data, and other information pertaining to the project area to assist in the evaluation of geologic hazards that may be present. Besides, pertinent information (the documents cited in Section 14, References) were used to understand the subsurface conditions and plan the investigation for this project.

4.2 Project Set-up

The project set-up consisted of the following tasks.

 Conducted a field reconnaissance and marked the boring locations.  Notified Underground Service Alert (USA) at least 48 hours prior to drilling to clear the boring locations of any conflict with existing underground utilities.  Coordinated with Kevin Lee from the City of Beaumont waste operator for access.  Engaged a California-licensed driller company to drill exploratory borings.

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4.3 Subsurface Exploration

Two exploratory borings (BH-01 and BH-02) was drilled on April 21, 2022, to investigate subsurface conditions at the project site. The borings were drilled using an 8-inch dimeter hollow stem auger to depths of 20.5 and 51.5 feet below existing ground surface (bgs).

Approximate boring location is indicated in Figure No. 2, Approximate Boring Locations Map. For a description of the field exploration and sampling program, see Appendix A, Field Exploration.

4.4 Laboratory Testing

Representative soil samples of the project site were tested in the laboratory to aid in the soils classification and to evaluate the relevant engineering properties of the soils. These tests included the following.

 In-situ moisture contents and dry densities (ASTM D2216 and ASTM D2937)  Expansion index (ASTM D4829)
 R-value (California Test 301)
 Soil corrosivity (California Tests 643, 422, and 417)  Collapse potential (ASTM D4546)
 Grain size distribution (ASTM D6913)
 Maximum dry density and optimum-moisture content (ASTM D1557)  Direct shear (ASTM D3080)
 Consolidation (ASTM D2435)

For in-situ moisture and dry density data, see the Logs of Borings in Appendix A, Field Exploration. For a description of the laboratory test methods and test results, see Appendix B, Laboratory Testing Program.

4.5 Analysis and Report Preparation

Data obtained from the field exploration and laboratory testing program was compiled and evaluated. Geotechnical analyses of the compiled data were performed, and this report was prepared to present our findings, conclusions, and recommendations for the project.

5.0 LABORATORY TEST RESULTS

Results of physical and chemical tests performed for this project are presented below.

5.1 Physical Testing

Results of the various laboratory tests are presented in Appendix B, Laboratory Testing Program, except for the results of in-situ moisture and dry density tests which are

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Project No.

Figure No.
20-81-289-01
Project:Mesa Lift Station Upgrades
Southeast Corner of the intersection of Potrero Blvd. & Castello Ln.

City of Beaumont, Riverside County, California
Location:

For:
2 Approximate Boring Locations Map
Albert Webb Associates
BH-02/ 20.5'
BH-01/ 51.5'
Number and Approximate Location of Exploratory Boring Number and Approximate Location of Exploratory BoringBH-02 75'0'

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presented on the Logs of Borings in Appendix A, Field Exploration. The results are also discussed below.

 In-situ Moisture and Dry Density – In-situ dry density and moisture content of the soils were determined in accordance with ASTM Standard D2216 and D2937. Dry density of upper 10 feet soils of the site ranged from 116 to 132 pcf with moisture contents ranging from 7 to 11 percent. Results are presented in the logs of boring in Appendix A, Field Exploration.
 Expansion Index (EI) –Two representative sample from the upper 5 feet of soils was tested to evaluate the expansion potential in accordance with ASTM Standard D4829. The tests results showed EI of 0 and 16, corresponding to very low expansion potential.
 R-value – (California Test 301) One representative bulk soil sample was performed by AP Engineering and Testing, Inc. (Pomona, CA) in accordance with California Test Method CT301 for resistance value (R-value). The test result showed R-value of 36.
 Collapse Potential – The collapse potential of two relatively undisturbed samples were tested under a vertical stress of up to 2.0 kips per square foot (ksf) in accordance with the ASTM Standard D4546 test method. The test results showed collapse potential of 0.7 and 1.0 percent, indicating slight collapse potential.  Grain Size Analysis – Four representative samples were tested to determine the relative grain size distribution in accordance with the ASTM Standard D6913. The test results are graphically presented in Drawing No. B-1, Grain Size Distribution Results.
 Maximum Dry Density and Optimum Moisture Content – Typical moisture-density relationship test was performed on two representative samples in accordance with ASTM D1557. The results are presented in Drawing No. B-2, Moisture-Density Relationship Results, in Appendix B, Laboratory Testing Program. The laboratory maximum dry densities were found 129.0 and 133.5 pcf and the optimum moisture content were found 9.0 and 9.2 percent.
 Direct Shear –Two direct shear tests were performed on undisturbed representative ring samples under soaked moisture condition in accordance with ASTM Standard D3080. The results are presented in Drawings No. B-3, Direct Shear Test Results in Appendix B, Laboratory Testing Program.  Consolidation Test – One consolidation test was performed on a relatively undisturbed sample of the site soil, in accordance with ASTM Standard D2435.

The test result is shown on Drawing No. B-5, Consolidation Test Results, in Appendix B, Laboratory Testing Program.

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5.2 Chemical Testing - Corrosivity Evaluation

Two representative soil samples were tested to determine minimum electrical resistivity, pH, and chemical content, including soluble sulfate and chloride concentrations. The purposes of these tests were to determine the corrosion potential of site soils when placed in contact with common construction and pipe materials. These tests were performed by AP Engineering and Testing, Inc. (Pomona, CA) in accordance with California Tests 643, 422, and 417. The test results are presented in Appendix B, Laboratory Testing Program and summarized below.

 The pH measurement of the tested samples was 8.5 and 8.7.  The sulfate content of the tested samples was 32 and 39 ppm.  The chloride concentration of the tested samples was 20 and 21 ppm.  The minimum electrical resistivity when saturated were 4,093 and 4,232 ohm-cm.

6.0 SITE CONDITIONS

A general description of the subsurface conditions, various materials and groundwater conditions encountered at the site during our field exploration is discussed below.

6.1 Subsurface Profile

Based on the exploratory borings and laboratory test results, the subsurface soils at the site encountered in the borings at various depths consists primarily of a mixture of sand, silt, and clay. For a detailed description of the subsurface materials encountered in the exploratory boring, see Drawing Nos. A-2a, A-2b and A-3, Logs of Borings, in Appendix A, Field Exploration.

6.2 Groundwater

Groundwater was not encountered during the investigation to the maximum explored depth of 51.5 feet bgs. For comparison, regional databases were accessed to search for relative groundwater level information, and the results are provided below.

The GeoTracker database (SWRCB, 2022) was reviewed to evaluate current and historical groundwater levels. No sites were identified within a 1.0-mile radius of the project site that contained groundwater elevation data.

The USGS National Water Information System (USGS, 2022) was reviewed to evaluate current and historical groundwater levels. Five results were returned in that search. Data from that record is listed in the table below.

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Table No. 1, Summary of USGS Groundwater Depth Data
Alignment No. Location Groundwater
Depth (ft. bgs)
Date
Range
335621117013501 Unnamed road; approximately
3,287 feet west of project site 39.08-51.80 1921-
2006
335709117004701 Morongo Golf Club; approximately
4,609 feet north of project site 244.00-255.40 1999-
2002
335640117002501 Desert Lawn; approximately 2,965
feet northeast of project site 152.90-165.80 1921-
1929
335603117000401 Western Lawn Ave.; approximately
4,645 feet southeast of project site 176.20-188.50 1998- 2021
335603117000601 Western Lawn Ave.; approximately
4,548 feet southeast of project site 90.60-143.28 1926- 2008

The California Department of Water Resources database (DWR, 2022) was reviewed to evaluate current and historical groundwater levels. No sites were identified within a 1.0- mile radius of the project site that contained groundwater elevation data.

Based on available data, the historical high groundwater level reported at wells within approximately one mile is 255.40 feet bgs. Groundwater was not encountered to a maximum explored depth of 51.5 feet during our exploratory boring and is not expected to be encountered during construction of the proposed project. It should be noted that the groundwater level could vary depending upon the seasonal precipitation and possible groundwater pumping activity in each site vicinity. Shallow perched groundwater may be present locally, particularly following precipitation or irrigation events.

6.3 Expansive Soils

Expansive soils are characterized by their ability to undergo significant volume changes (shrink or swell) due to variations in moisture content. Changes in soil moisture content can result from precipitation, landscape irrigation, utility leakage, roof drainage, perched groundwater, drought, or other factors and may result in unacceptable settlement or heave of structures or concrete slabs supported on grade. Depending on the extent and location below finish subgrade, expansive soils can have a detrimental effect on structures. Based on the laboratory test results, the expansion index of the upper 5 feet of site soil were 0 and16, corresponds to very low expansion potential.

6.4 Collapse Potential

Soil deposits subjected to collapse/hydro-consolidation generally exist in regions of moisture deficiency. Collapsible soils are generally defined as soils that have potential to suddenly decrease in volume upon increase in moisture content even without an increase in external loads. Moreover, some soils may have a different degree of collapse/hydro-

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consolidation based on the amount of proposed fill or structure loads. Soils susceptible to collapse/ hydro-consolidation include wind-blown silt, weakly cemented sand, and silt where the cementing agent is soluble (e.g., soluble gypsum, halite), alluvial or colluvial deposits within semi‐arid to arid climate, and certain weathered bedrock above the groundwater table.

Granular soils may have a potential to collapse upon wetting in arid climate regions.

Collapse/hydro-consolidation may occur when the soluble cements (carbonates) in the soil matrix dissolve, causing the soil to densify from its loose/low density configuration from deposition.

The degree of collapse of a soil can be defined by the collapse potential value, which is expressed as a percent of collapse of the total sample using the Collapse Potential Test (ASTM D4546). According to the ASTM guideline, the severity of collapse potential is commonly evaluated by the following Table No. 2, Collapse Potential Values.

Table No. 2, Collapse Potential Values
Collapse Potential Value (%) Severity of Problem
0 None

0.1 to 2 Slight

2.1 to 6.0 Moderate

6.0 to 10.0 Moderately Severe
>10 Severe

Based on the laboratory test results (collapse potential of 0.7 and 1.0 percent), a slight problem is anticipated at the site. Collapse potential distress is typically considered a concern when collapse potential is over 2% (LA County, 2013).

6.5 Excavatability

The surface and subsurface soil materials at the site are expected to be excavatable by conventional heavy-duty earth moving and trenching equipment.

The phrase “conventional heavy-duty excavation equipment” is intended to include commonly used equipment such as excavators and trenching machines. It does not include hydraulic hammers (“breakers”), jackhammers, blasting, or other specialized equipment and techniques used to excavate hard earth materials. Selection of an appropriate excavation equipment model should be done by an experienced earthwork contractor and may require test excavations in representative areas.

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6.6 Subsurface Variations

Based on results of the subsurface exploration and our experience, some variations in the continuity and nature of subsurface conditions within the project site should be anticipated. Because of the uncertainties involved in the nature and depositional characteristics of the earth material, care should be exercised in interpolating or extrapolating subsurface conditions between or beyond the boring locations.

7.0 ENGINEERING GEOLOGY

The regional and local geology within the proposed project area is discussed below.

7.1 Regional Geology

The proposed project site is located within the northern Peninsular Ranges Geomorphic Province of Southern California. The Peninsular Ranges Geomorphic Province consists of a series of northwest-trending mountain ranges and valleys bounded on the north by the San Bernardino and San Gabriel Mountains, on the west by the Los Angeles Basin, and on the southwest by the Pacific Ocean.

The province is a seismically active region characterized by a series of northwest-trending strike-slip faults. The most prominent of the nearby fault zones include the San Jacinto and Elsinore faults, as well as the San Gorgonio and San Andreas fault zones (CGS, 2007), all of which have been known to be active during Quaternary time.

Topography within the province is generally characterized by broad alluvial valleys separated by linear mountain ranges. This northwest-trending linear fabric is created by the regional faulting within the granitic basement rock of the Southern California Batholith.

Broad, linear, alluvial valleys have been formed by erosion of these principally granitic mountain ranges.

7.2 Local Geology

The project site is located on south-sloping alluvial fan within the San Gorgonio Pass, just north of the Badlands Mountain Range. Regional mapping (Matti and Morton, 2015) indicates that the subsurface is characterized by Pleistocene-aged alluvial fan deposits of sand and gravel from plutonic and gneissic detritus derived from the rising San Bernardino Mountains to the north and the Badlands Mountains to the south.

8.0 FAULTING AND SEISMICITY

The approximate distance and seismic characteristics of nearby faults as well as seismic design coefficients are presented in the following subsections.

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8.1 Faulting

The proposed site is situated in a seismically active region. As is the case for most areas of Southern California, ground-shaking resulting from earthquakes associated with nearby and more distant faults may occur at the project site. During the life of the project, seismic activity associated with active faults can be expected to generate moderate to strong ground shaking at the site. Review of recent seismological and geophysical publications indicates that the seismic hazard for the project is high.

The project site is not located within a currently mapped State of California Earthquake Fault Zone for surface fault rupture. Table No. 3, Summary of Regional Faults, summarizes selected data of known faults capable of seismic activity within 100 kilometers of the site. The data presented below was calculated using the National Seismic Hazard Maps Database (USGS, 2008) and other published geologic data.

Table No. 3, Summary of Regional Faults
Fault Name and Section
Closest
Distance
(km)
Slip Sense Length
(km)
Slip Rate
(mm/year)
Maximum
Magnitude
San Jacinto 7.79 strike slip 241 n/a 7.88
S. San Andreas 13.67 strike slip 548 n/a 8.18
Pinto Mtn 30.06 strike slip 74 2.5 7.30
Cleghorn 41.82 strike slip 25 3 6.80
Elsinore 43.32 strike slip 241 n/a 7.85
Helendale-So Lockhart 46.49 strike slip 114 0.6 7.40
Cucamonga 47.52 thrust 28 5 6.70
North Frontal (West) 47.67 reverse 50 1 7.20
North Frontal (East) 48.28 thrust 27 0.5 7.00
Chino, alt 2 52.52 strike slip 29 1 6.80
Chino, alt 1 54.69 strike slip 24 1 6.70
Lenwood-Lockhart-Old
Woman Springs 56.95 strike slip 145 0.9 7.50
Burnt Mtn 57.25 strike slip 21 0.6 6.80
Landers 60.41 strike slip 95 0.6 7.40
Eureka Peak 60.78 strike slip 19 0.6 6.70
San Jose 65.23 strike slip 20 0.5 6.70
Johnson Valley (No) 65.98 strike slip 35 0.6 6.90
Sierra Madre 69.94 reverse 57 2 7.20
Sierra Madre Connected 69.94 reverse 76 2 7.30
San Joaquin Hills 71.92 thrust 27 0.5 7.10
So Emerson-Copper Mtn 75.91 strike slip 54 0.6 7.10
Puente Hills (Coyote Hills) 78.93 thrust 17 0.7 6.90

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Fault Name and Section
Closest
Distance
(km)
Slip Sense Length
(km)
Slip Rate
(mm/year)
Maximum
Magnitude
Calico-Hidalgo 82.69 strike slip 117 1.8 7.40
Clamshell-Sawpit 83.56 reverse 16 0.5 6.70
Newport Inglewood
Connected alt 1 86.23 strike slip 208 1.3 7.50
Newport-Inglewood
(Offshore) 86.23 strike slip 66 1.5 7.00
Newport Inglewood
Connected alt 2 86.23 strike slip 208 1.3 7.50
Pisgah-Bullion Mtn-
Mesquite Lk 91.04 strike slip 88 0.8 7.30
Newport-Inglewood, alt 1 92.52 strike slip 65 1 7.20
(Source: https://earthquake.usgs.gov/cfusion/hazfaults_2008_search/)

8.2 CBC Seismic Design Parameters

Seismic parameters based on the 2019 California Building Code (CBSC, 2019) and ASCE 7-16 are provided in the following table. These parameters were determined using the generalized coordinates (33.940261N, 117.016129W) and the Seismic Design Maps ATC online tool.

Table No. 4, CBC Seismic Design Parameters
Seismic Parameters
Site Coordinates 33.940261N,
117.0116129W
Risk Category III
Site Class D
Mapped Short period (0.2-sec) Spectral Response Acceleration, SS 1.701g Mapped 1-second Spectral Response Acceleration, S1 0.623g Site Coefficient (from Table 11.4-1), Fa 1.0
Site Coefficient (from Table 11.4-2), Fv 1.7
MCE 0.2-sec period Spectral Response Acceleration, SMS 1.701g MCE 1-second period Spectral Response Acceleration, SM1 1.059g Design Spectral Response Acceleration for short period SDS 1.134g Design Spectral Response Acceleration for 1-second period, SD1 0.706g Site Modified Maximum Peak Ground Acceleration, PGAM 0.762g

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8.3 Secondary Effects of Seismic Activity

In general, secondary effects of seismic activity include surface fault rupture, soil liquefaction, landslides, lateral spreading, and settlement due to seismic shaking, tsunamis, seiches, and earthquake-induced flooding. The site-specific potential for each of these seismic hazards is discussed in the following sections.

Surface Fault Rupture: The project site is not located within a currently designated State of California or Riverside County Earthquake Fault Zone (CGS, 2007; Riverside County, 2022). There are no known active faults projecting toward or extending across the project site. The potential for surface rupture resulting from the movement of nearby major faults is not known with certainty but is considered low.

Liquefaction: Liquefaction is defined as the phenomenon in which a cohesionless soil mass within the upper 50 feet of the ground surface suffers a substantial reduction in its shear strength, due to the development excess pore pressures. During earthquakes, excess pore pressures in saturated soil deposits may develop as a result of induced cyclic shear stresses, resulting in liquefaction.

Soil liquefaction generally occurs in submerged granular soils and non-plastic silts during or after strong ground shaking. There are several general requirements for liquefaction to occur and they are as follows.

 Soils must be submerged.
 Soils must be loose to medium-dense.
 Ground motion must be intense.
 Duration of shaking must be sufficient for the soils to lose shear resistance.

Based on a review of state and county hazard maps, the project site is located within an area not evaluated for liquefaction by State of California (CGS, 2007). The project site is located within a Riverside County (Riverside County, 2022) liquefaction zone designated as a low liquefaction potential. Based on the dynamic Settlement Analyses presented in Appendix C, Liquefaction and Seismic Settlement Analysis, we estimate that the liquefaction induced settlement potential for the site is negligible.

Seismic Settlement: Dynamic dry settlement may occur in loose, granular, unsaturated soils during a large seismic event. Classification of the samples and sampling blow counts indicate that the site is medium dense to dense and are sensitive to some seismically induced settlement. The potential for dry seismic settlement is not known with certainty, however due to the lack of shallow groundwater in the area the potential is considered negligible. Based on the dynamic Settlement Analyses presented in Appendix C, Liquefaction and Seismic Settlement Analysis, we estimate that the dry seismic settlement potential for the site is up to 0.4 inches.

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Landslides: Seismically induced landslides and slope failures are common occurrences during or soon after large earthquakes. Due to the flat nature of the site and the distance away from any foothills, the potential for seismically induced landslides affecting the proposed site is considered to be very low.

Lateral Spreading: Seismically induced lateral spreading involves primarily lateral movement of earth materials over underlying materials which are liquefied due to ground shaking. It differs from the slope failure in that complete ground failure involving large movement does not occur due to the relatively smaller gradient of the initial ground surface.

Lateral spreading is demonstrated by near-vertical cracks with predominantly horizontal movement of the soil mass involved. The topography at the project site and in the immediate vicinity is very flat. Under these circumstances, the potential for lateral spreading at the subject site is considered low.

Tsunamis: Tsunamis are large waves generated in open bodies of water by fault displacement or major ground movement. Due to the inland location of the site, tsunamis are not considered to be a risk.

Seiches: Seiches are large waves generated in enclosed bodies of water in response to ground shaking. Due to the site far distance from bodies of water, seiches are not considered to be a risk.

Earthquake-Induced Flooding: Dams or other water-retaining structures may fail as a result of large earthquakes. Dams or other water-retaining structures may fail as a result of large earthquakes. The project site is not located within a designated dam inundation area (DSOD, 2022).

9.0 EARTHWORK RECOMMENDATIONS

Earthwork recommendations for the project are presented in the following sections.

9.1 General

This section contains our general recommendations regarding earthwork and grading for the project. These recommendations are based on the results of our field exploration, laboratory tests, our experience with similar projects, and data evaluation as presented in the preceding sections. These recommendations may require modification by the geotechnical consultant based on observation of the actual field conditions during grading.

Prior to the start of construction, all existing underground utilities and appurtenances should be located at the project site. Such utilities should either be protected in-place or removed and replaced during construction as required by the project specifications. All excavations should be conducted in such a manner as not to cause loss of bearing and/or

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lateral support of existing utilities. All debris and deleterious material should be removed from the site.

If isolated pockets of very soft, loose, eroded, or pumping soil are encountered, the unstable soil should be excavated as needed to expose undisturbed, firm, and unyielding soils.

The contractor should determine the best manner to conduct the excavations, such that there are no losses of bearing and/or lateral support to the existing utilities (if any).

The final bottom surfaces of all excavations should be observed and approved by the project geotechnical consultant prior to placing any fill. Based on these observations, localized areas may require remedial grading deeper than indicated herein. Therefore, some variations in the depth and lateral extent of excavation recommended in this report should be anticipated.

9.2 Remedial Grading

Footings, slab-on-grade, concrete pads and pavements should be uniformly supported by compacted fill. In order to provide uniform support, structural areas should be overexcavated, scarified, and recompacted as follows.

Table No. 5, Overexcavation Depths
Structure/Pavement Minimum Excavation Depth
Footings 24 inches below footings bottom or 3 feet below existing ground surface, whichever is deeper
Tank Bottom 5 feet below tank bottom footing and to extend at least 3 feet beyond the footprint of tank footings.

Slabs-on-grade 12 inches below slab bottom or 3 feet below existing ground surface, whichever is deeper
Concrete Pads 12 inches below pad bottom or 3 feet below existing ground surface, whichever is deeper
Pavements 12 inches below finish grade

The overexcavation below the footings, slab-on-grade, concrete pads and pavements should be uniform. The overexcavation should extend to at least 2 feet beyond the footprint of the slabs and pads, and at least 1 foot beyond the edge of the pavements.

The overexcavation bottom should be scarified and compacted as described in Section

9.4, Compacted Fill Placement.

If isolated pockets of very soft, loose, eroded, or pumping soil are encountered, the unstable soil should be excavated as needed to expose undisturbed, firm, and unyielding soils.

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The contractor should determine the best manner to conduct the excavations, such that there are no losses of bearing and/or lateral support to the existing structures or utilities.

Footings, slab-on-grade and concrete pad should be uniformly supported by compacted fill.

In order to provide uniform support, structural areas should be generally overexcavated, scarified, and recompacted as follows.

9.3 Structural/Engineered Fill

No fill or aggregate base should be placed until excavations and/or natural ground preparation have been observed by the geotechnical consultant. The native soils encountered within the project site are generally considered suitable for re-use as compacted fill. Excavated soils should be processed, including removal of roots and debris, removal of oversized particles, mixing, and moisture conditioning, before placing as compacted fill. On-site soils used as fill should meet the following criteria.

 No particles larger than 3 inches in largest dimension.  Rocks larger than one inch should not be placed within the upper 12 inches of subgrade soils.
 Free of all organic matter, debris, or other deleterious material.  Expansion index of 40 or less.
 Sand Equivalent greater than 15 (greater than 30 for pipe bedding).  Contain less than 30 percent by weight retained in 3/4-inch sieve.  Contain less than 40 percent fines (passing #200 sieve).

Based on field investigation and laboratory testing results, on-site soils may be suitable as fill materials.

Imported materials, if required, should meet the above criteria prior to being used as compacted fill. Any imported fills should be tested and approved by geotechnical representative prior to delivery to the site.

9.4 Compacted Fill Placement

All surfaces to receive structural fills should be scarified to a depth of 6 inches. The soil should be moisture conditioned to within ±3 percent of optimum moisture content for coarse soils and 0 to 2 percent above optimum moisture content for fine soils. The scarified soils should be recompacted to at least 90 percent of the laboratory maximum dry density.

Fill soils should be thoroughly mixed, and moisture conditioned to within ±3 percent of optimum moisture content for coarse soils and 0 to 2 percent above optimum moisture content for fine soils. Fill soils should be evenly spread in horizontal lifts not exceeding 8 inches in uncompacted thickness.

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All fill placed at the site should be compacted to at least 90 percent of the laboratory maximum dry densities as determined by ASTM Standard D1557 test method unless a higher compaction is specified herein.

To reduce differential settlement, variations in the soil type, degree of compaction and thickness of the engineered fill placed underneath the foundations should be minimized.

Fill materials should not be placed, spread, or compacted during unfavorable weather conditions. When site grading is interrupted by heavy rain, filling operations should not resume until the geotechnical consultant approves the moisture and density conditions of the previously placed fill.

9.5 Backfill Recommendations Behind Subterranean Wall

Compaction of backfill adjacent to structural walls can produce excessive lateral pressures. Improper types and locations of compaction equipment and/or compaction techniques may damage the walls. The use of heavy compaction equipment should not be permitted within a horizontal distance of 5 feet from the wall. Backfill behind any structural walls within the recommended 5-foot zone should be compacted using lightweight construction equipment such as handheld compactors to avoid overstressing the walls. The compaction of wall backfill should be conducted procedure described in section 9.4 Compaction Fill Placement.

9.6 Shrinkage and Subsidence

The volume of excavated and recompacted soils will decrease as a result of grading. The shrinkage would depend on, among other factors, the depth of cut and/or fill, and the grading method and equipment utilized. Based on our previous experience in the other projects in close vicinity of this site, for the preliminary estimation, shrinkage factors for various units of earth material at the site may be taken as presented below.

 The shrinkage factor (defined as a percentage of soil volume reduction when moisture conditioned and compacted to the average of 92 percent relative compaction) of fill is estimated. An average value of 3 percent may be used for preliminary earthwork planning.
 Subsidence (defined as the settlement of native materials from the equipment load applied during grading) would depend on the construction methods including type of equipment utilized. Ground subsidence is estimated to be approximately 0.1 foot to

0.15 foot.

Although these values are only approximate, they represent our best estimates of the factors to be used to calculate lost volume that may occur during grading. If more accurate shrinkage and subsidence factors are needed, it is recommended that field-testing using the actual equipment and grading techniques be conducted.

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9.7 Site Drainage

Adequate positive drainage should be provided away from the site and excavation areas to prevent ponding and to reduce percolation of water into the foundation soils. Surface drainage should be directed to suitable non-erosive devices.

9.8 Utility Trench Backfill

The following sections present earthwork recommendations for utility trench backfill, including subgrade preparation and trench zone backfill.

Open cuts adjacent to existing roadways or structures are not recommended within a 1:1 (horizontal:vertical) plane extending down and away from the roadway or structure perimeter (if any).

Soils from the trench excavation should not be stockpiled more than 6 feet in height or within a horizontal distance from the trench edge equal to the depth of the trench. Soils should not be stockpiled behind the shoring, if any, within a horizontal distance equal to the depth of the trench, unless the shoring has been designed for such loads.

9.8.1 Pipeline Subgrade Preparation

The final subgrade surface should be level, firm, uniform, and free of loose materials and properly graded to provide uniform bearing and support to the entire section of the pipe placed on bedding material. Protruding oversize particles larger than 2 inches in dimension, if any, should be removed from the trench bottom and replaced with compacted on-site materials.

Any loose, soft and/or unsuitable materials encountered at the pipe subgrade should be removed and replaced with an adequate bedding material. During the digging of depressions for proper sealing of the pipe joints, the pipe should rest on a prepared bottom for as near its full length as is practicable.

9.8.2 Pipe Bedding

Bedding is defined as the material supporting and surrounding the pipe to 1 foot above the pipe. Pipe bedding should follow City of Beaumont Standards. If additional recommendations beyond City of Beaumont Standards are needed, the following specifications can be used during the placement of pipe bedding.

To provide uniform and firm support for the pipe, compacted granular materials such as clean sand, gravel or ¾-inch crushed aggregate, or crushed rock may be used as pipe bedding material. Typically, soils with sand equivalent value of 30 or more are used as

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pipe bedding material. The pipe designer should determine if the soils are suitable as pipe bedding material.

The type and thickness of the granular bedding placed underneath and around the pipe, if any, should be selected by the pipe designer. The load on the rigid pipes and deflection of flexible pipes and, hence, the pipe design, depends on the type and the amount of bedding placed underneath and around the pipe.

Bedding materials should be vibrated in-place to achieve compaction. Care should be taken to densify the bedding material below the springline of the pipe. Prior to placing the pipe bedding material, the pipe subgrade should be uniform and properly graded to provide uniform bearing and support to the entire section of the pipe placed on bedding material. During the digging of depressions for proper sealing of the pipe joints, the pipe should rest on a prepared bottom for as near its full length as is practicable.

Migration of fines from the surrounding native and/or fill soils must be considered in selecting the gradation of any imported bedding material. We recommend that the pipe bedding material should satisfy the following criteria to protect migration of fine materials.

i. 𝐷𝐷15(𝐹𝐹)𝐷𝐷85(𝐵𝐵)≤5
ii. 𝐷𝐷50(𝐹𝐹)𝐷𝐷50(𝐵𝐵)<25
iii. Bedding Materials must have less than 5 percent passing No. 200 sieve (0.0074 mm) to avoid internal movement of fines.

Where,
F = Bedding Material
B = Surrounding Native and/or Fill Soils
D15(F) = Particle size through which 15% of bedding material will pass D85(B) = Particle size through which 85% of surrounding soil will pass D50(F) = Particle size through which 50% of bedding material will pass D50(B) = Particle size through which 50% of surrounding soil will pass

If the above criteria do not satisfy, commercially available geofabric used for filtration purposes (such as Mirafi 140N or equivalent) may be wrapped around the bedding material encasing the pipe to separate the bedding material from the surrounding native or fill soils.

9.8.3 Trench Zone Backfill

The trench zone is defined as the portion of the trench above the pipe bedding extending up to the final grade level of the trench surface. Excavated site soil free of oversize particles and deleterious matter may be used to backfill the trench zone. Trench backfill

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should follow City of Beaumont. If additional recommendations beyond the City Standards are needed, the following specifications can be used during the placement of trench backfill.

 Trench excavations to receive backfill should be free of trash, debris or other unsatisfactory materials at the time of backfill placement.  Trench zone backfill should be compacted to at least 90 percent of the laboratory maximum dry density as per ASTM D1557 test method. At least the upper 1 foot of trench backfill underlying pavement should be compacted to at least 95 percent of the laboratory maximum dry density as per ASTM D1557 test method.  Particles larger than 1 inch should not be placed within 12 inches of the pavement subgrade. No more than 30 percent of the backfill volume should be larger than ¾-inch in the largest dimension. Gravel should be well mixed with finer soil. Rocks larger than 3 inches in the largest dimension should not be placed as trench backfill.
 Trench backfill should be compacted by mechanical methods, such as sheepsfoot, vibrating or pneumatic rollers or mechanical tampers to achieve the density specified herein. The backfill materials should be brought to within ± 3 percent of optimum moisture content for coarse-grained soil, and between optimum and 2 percent above optimum for fine-grained soil, then placed in horizontal layers. The thickness of uncompacted layers should not exceed 8 inches. Each layer should be evenly spread, moistened or dried as necessary, and then tamped or rolled until the specified density has been achieved.
 The contractor should select the equipment and processes to be used to achieve the specified density without damage to adjacent ground, structures, utilities and completed work.
 The field density of the compacted soil should be measured by the ASTM D1556 (Sand Cone) or ASTM D6938 (Nuclear Gauge) or equivalent.  Observations and field tests should be performed by the project soils consultant to confirm that the required degree of compaction has been obtained. Where compaction is less than that specified, additional compactive effort should be made with adjustment of the moisture content as necessary, until the specified compaction is obtained.
 It should be the responsibility of the contractor to maintain safe working conditions during all phases of construction.
 Trench backfill should not be placed, spread or rolled during unfavorable weather conditions. When the work is interrupted by heavy rain, fill operations should not resume until field tests by the project’s geotechnical consultant indicate that the moisture content and density of the fill are in compliance with project specifications.

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10.0 DESIGN RECOMMENDATIONS

The various design recommendations provided in this section are based on the assumption that the above earthwork and grading recommendations will be implemented in the project design and construction.

10.1 Shallow Foundation Design Parameters

The proposed equipment pads and walls may be supported on continuous spread and/or isolated spread footings. The design of the shallow foundations should be based on the recommended parameters presented in the table below.

Table No. 6, Recommended Foundation Parameters
Parameter Value
Minimum continuous footing width 18 inches
Minimum isolated footing width 18 inches
Minimum continuous or isolated footing depth of embedment below lowest adjacent grade 18 inches
Allowable net bearing capacity 3,500 psf

The actual footing dimensions and reinforcement should be based on structural design.

The allowable bearing capacity can be increased by 500 psf with each foot of additional embedment and 100 psf with each foot of additional width up to a maximum of 4,500 psf.

The net allowable bearing values indicated above are for the dead loads and frequently applied live loads and are obtained by applying a factor of safety of 3.0 to the net ultimate bearing capacity. If normal code requirements are applied for design, the above vertical bearing value may be increased by 33 percent for short duration loadings, which will include loadings induced by wind or seismic forces.

10.2 Mat Foundation Design Parameters

The proposed equipment pad may be designed as mat foundation. The modulus of subgrade reaction (k) for design of flexible mat foundation was estimated from the available soil compressibility data and published charts. For design of flexible mat foundation, the following equation may be used.

k= k1[(B+1)/2B]2

Where:
k= vertical modulus of subgrade reaction for mat foundation, kips per cubic feet k1= 200 kcf, normalized modulus of subgrade reaction for 1-square-foot footing B= foundation width, feet

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Other necessary parameters (modulus of elasticity and Poisson’s ratio) for mat foundation design are as follows.

E= 33 Wc1.5 fc 0.5 psi
Where, E = Modulus of Elasticity of Concrete (psi)
Wc = weight of concrete (pcf)
fc = compressive strength of concrete at 28 days (psi)
ν = 0.35, Poisson’s Ratio

An allowable net bearing capacity of 3,500 psf may be used for mat foundations founded on compacted native soil. The mat should be reinforced with top and bottom steel, as appropriate, to provide structural continuity and to permit spanning of local irregularities.

The mat foundation dimensions, and reinforcement should be based on structural design.

For design purposes, the self-weight of the mat foundation can be negligible.

10.3 Soil Parameters for Pipe Design

Structural design requires proper evaluation of all possible loads acting on pipe. The stresses and strains induced on buried pipe depend on many factors, including the type of soil, density, bearing pressure, angle of internal friction, coefficient of passive earth pressure, and coefficient of friction at the interface between the backfill and native soils.

The recommended values of the various soil parameters for design are provided in the following table.

Table No. 7, Soil Parameters for Pipe Design
Soil Parameters Value
Average compacted fill total unit weight (assuming 92%
relative compaction), γ (pcf) 140
Angle of internal friction of soils, φ 33
Soil cohesion, c (psf) 80
Coefficient of friction between concrete and native soils, fs 0.35 Coefficient of friction between steel pipe and native soils, fs 0.25 Bearing pressure against native soils (psf) 3,500
Coefficient of passive earth pressure, Kp 3.39
Coefficient of active earth pressure, Ka 0.29
Modulus of Soil Reaction E’ (psi) 1,500

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10.4 Bearing Pressure for Anchor and Thrust Blocks

An allowable net bearing pressure presented in Table No. 7, Soil Parameters for Pipe Design may be used for anchor and thrust block design against alluvial soils. Such thrust blocks should be at least 18 inches wide.

If normal code requirements are applied for design, the above recommended bearing capacity and passive resistances may be increased by 33 percent for short duration loading such as seismic or wind loading.

10.5 Lateral Earth Pressures and Resistance to Lateral Loads

In the following subsections, the lateral earth pressures and resistance to lateral loads are estimated by using on-site native soils strength parameters obtained from laboratory testing.

10.5.1 Active Earth Pressures

The active earth pressure behind any buried wall or foundation depends primarily on the allowable wall movement, type of backfill materials, backfill slopes, wall or foundation inclination, surcharges, and any hydrostatic pressures. The lateral earth pressures are presented in the following table.

Table No. 8, Active and At-Rest Earth Pressures
Loading Conditions Lateral Earth Pressure
(psf/ft depth)
Active earth conditions (wall is free to deflect at least 0.001 radian) 38 At-rest (wall is restrained) 59

These pressures assume no surcharge, and no hydrostatic pressure. If water pressure is allowed to build up behind the walls, the active pressures should be reduced by 50 percent and added to a full hydrostatic pressure to compute the design pressures against the walls.

A uniform lateral pressure of 100 psf should be considered to account for normal vehicular and construction traffic within 10 feet of the structures.

10.5.2 Resistance to Lateral Loads

Resistance to lateral loads can be assumed to be provided by a combination of friction acting at the base of foundations and by passive earth pressure. A coefficient of friction of 0.35 between formed concrete and soil may be used with the dead load forces. An allowable passive earth pressure of 200 psf per foot of depth may be used for the sides of the footing poured against recompacted native soils. A factor of safety of 1.5 was applied in calculating

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passive earth pressure. The maximum value of the passive earth pressure should be limited to 3,500 psf.

Vertical and lateral bearing values indicated above are for the total dead loads and frequently applied live loads. If normal code requirements are applied for design, the above vertical bearing and lateral resistance values may be increased by 33 percent for short duration loading, which will include the effect of wind or seismic forces.

Due to the low overburden stress of the soil at shallow depth, the upper 1 foot of passive resistance should be neglected unless the soil is confined by pavement or slab.

10.5.3 Seismic Earth Pressure

The seismic force applied to the wall is based on a horizontal seismic acceleration coefficient equal to one-third of the peak ground. An equivalent fluid seismic pressure of 27H pcf may be assumed under active loading conditions (regular triangular pressure distribution) where H is the height of the backfill behind the wall.

10.6 Settlement

The total settlement of mat foundation from static structural loads and short-term settlement of properly compacted fill is anticipated to be 1 inch or less. The differential settlement resulting from static loads is anticipated to be 0.5 inches or less over a horizontal distance of 40 feet.

Our analysis of the potential dynamic settlement is presented in Appendix C, Liquefaction and Settlement Analysis. We estimate that the site has negligible potential for liquefaction induced settlement with up to 0.4 inches of dry seismic settlement. The soil profile across the site is relatively similar. So, we anticipate that the total settlement will be uniform. We recommend that the planned structure be designed in anticipation of dynamic differential settlement of 0.5 inches in 40 horizontal feet.

Generally, the static and dynamic settlement does not occur at the same time. For design purposes, the structural engineer should decide whether static and dynamic settlement will be combined or not.

10.7 Soil Corrosivity

Two representative soil sample was evaluated for corrosivity with respect to common construction materials such as concrete and steel. The test results are presented in Appendix B, Laboratory Testing Program and general discussion of the test results are presented below. However, Converse does not practice in the area of corrosion consulting and cannot provide mitigation recommendations.

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Soil pH values were found 8.5 and 8.7, which indicates soil is alkaline in nature.

The sulfate contents of the sampled soil correspond to American Concrete Institute (ACI) exposure category S0 for the sulfate concentration (ACI 318-14, Table 19.3.1.1). No concrete type restrictions are specified for exposure category S0 (ACI 318-14, Table

19.3.2.1). A minimum compressive strength of 2,500 psi is recommended.

We anticipate that concrete will be exposed to moisture from precipitation and irrigation.

Based on the project location and the results of chloride testing of the soils, we do not anticipate that concrete structures will be exposed to external sources of chlorides, such as deicing chemicals, salt, brackish water, or seawater. ACI specifies exposure category C1 where concrete is exposed to moisture, but not to external sources of chlorides (ACI 318-14, Table 19.3.1.1). ACI provides concrete design recommendations in ACI 318-14, Table 19.3.2.1, including a compressive strength of at least 2,500 psi and a maximum chloride content of 0.3 percent.

According to Romanoff, 1957, the following table provides general guideline of soil corrosion based on electrical resistivity.

Table No. 9, Correlation Between Resistivity and Corrosion Soil Resistivity (ohm-cm) per Caltrans CT 643 Corrosivity Category Over 10,000 Mildly corrosive
2,000 – 10,000 Moderately corrosive
1,000 – 2,000 corrosive
Less than 1,000 Severe corrosive

The measured value of the minimum electrical resistivity of the sample when saturated were 4,093 and 4,232 ohm-cm for the site. This indicates that the soils tested are moderately corrosive to ferrous metals in contact with the soil. If needed, a qualified corrosion consultant should provide appropriate corrosion mitigation measures for any ferrous metals and concrete materials in contact with the site soils.

10.8 Asphalt Concrete Pavement

For pavement design, we have utilized design R-value of 36 and Traffic Indices (TIs) ranging from 5 to 8.

Based on the above information, asphalt concrete and aggregate base thickness are determined using the Caltrans Highway Design Manual (Caltrans, 2021), Chapter 630 with a safety factor of 0.2 for asphalt concrete/aggregate base Section and 0.1 for full depth asphalt concrete section. Minimum TI, asphalt pavement and aggregate base

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thickness requirements were also considered in the pavement designs. Preliminary asphalt concrete pavement sections for each street are presented in the following table.

Table No. 10, Recommended Pavement Sections
Design R-
value
Traffic
Index
(TI)
Pavement Section
Asphalt Concrete
(inches)
Aggregate Base
(inches)
Full AC Section
(inches)
36 5.0 3.0 4.5 5.5

6.0 4.0 5.0 7.0

7.0 4.5 7.0 8.0

8.0 5.5 8.0 9.5

Pavement sections should follow Table No. 10, Recommended Pavement Sections or the City of Beaumont Standards, whichever is applicable. At or near the completion of grading, the subgrade should be tested to evaluate the actual subgrade R-value for final pavement design.

Prior to placement of aggregate base or asphalt concrete, at least the upper 12 inches of subgrade soils should be scarified, moisture-conditioned if necessary, and recompacted to at least 95 percent of the laboratory maximum dry density as defined by ASTM Standard D1557 test method.

Base materials should conform to Section 200-2.2,"Crushed Aggregate Base," of the current Standard Specifications for Public Works Construction (SSPWC; Public Works Standards, 2018) or the City of Beaumont Standards, whichever is applicable and should be placed in accordance with Section 301-2 of the SSPWC.

Asphaltic concrete materials should conform to Section 203 of the SSPWC or the City of Beaumont Standards, whichever is applicable and should be placed in accordance with Section 302-5 of the SSPWC.

11.0 CONSTRUCTION RECOMMENDATIONS

Temporary sloped excavation and shoring design recommendations are presented in the following sections.

11.1 General

Prior to the start of construction, all existing underground utilities should be located at the project site. Such utilities should either be protected in-place or removed and replaced during construction as required by the project specifications.

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Sloped excavations may not be feasible in locations adjacent to existing utilities, pavement, or structures. Recommendations pertaining to temporary excavations are presented in this section.

Excavations near existing structures may require vertical side wall excavation. Where the side of the excavation is a vertical cut, it should be adequately supported by temporary shoring to protect workers and any adjacent structures.

All applicable requirements of the California Construction and General Industry Safety Orders, the Occupational Safety and Health Act, and the Construction Safety Act should be met. The soils exposed in cuts should be observed during excavation by the geotechnical consultant and the competent person designated by the contractor. If potentially unstable soil conditions are encountered, modifications of slope ratios for temporary cuts may be required.

11.2 Temporary Sloped Excavations

Temporary open-cut trenches may be constructed with side slopes as recommended in the following table. Temporary cuts encountering soft and wet fine-grained soils; dry loose, cohesionless soils or loose fill from trench backfill may have to be constructed at a flatter gradient than presented below.

Table No. 11, Slope Ratios for Temporary Excavations
Soil Type OSHA Soil
Type
Depth of Cut
(feet)
Recommended Maximum
Slope (Horizontal:Vertical)1
Sandy Silt (ML), Silty
Sand (SM)* C 0-10 1.5:1
* Slope ratio assumed to be uniform from top to toe of slope.

For shallow excavations up to 4 feet bgs can be vertical. For steeper temporary construction slopes or deeper excavations, or unstable soil encountered during the excavation, shoring or trench shields should be provided by the contractor to protect the workers in the excavation.

Surfaces exposed in slope excavations should be kept moist but not saturated to retard raveling and sloughing during construction. Adequate provisions should be made to protect the slopes from erosion during periods of rainfall. Surcharge loads, including construction materials, should not be placed within 5 feet of the unsupported slope edge.

Stockpiled soils with a height higher than 6 feet will require greater distance from trench edges.

Geotechnical Investigation Report
Mesa Lift Station Upgrades
Southeast Corner of the Intersection of Potrero Boulevard and Castello Lane City of Beaumont, Riverside County, California
June 23, 2022

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11.3 Shoring Design

Temporary shoring will be required where open sloped excavations will not be feasible due to unstable soils or due to nearby existing structures or facilities. Temporary shoring may consist of conventional soldier piles and lagging or sheet piles or any piles selected by contractor. The shoring for the pipe excavations may be laterally supported by walers and cross bracing or may be cantilevered. Drilled excavations for soldier piles will require the use of drilling fluids to prevent caving and to maintain an opened hole for pile installation.

The active earth pressure behind any shoring depends primarily on the allowable movement, type of backfill materials, backfill slopes, wall inclination, surcharges, and any hydrostatic pressures.

The lateral earth pressures to be used in the design of shoring is presented in the following table.

Table No. 12, Lateral Earth Pressures for Temporary Shoring Lateral Resistance Soil Parameters* Value
Active Earth Pressure (Braced Shoring) (psf) (A) 26
Active Earth Pressure (Cantilever Shoring) (psf) (B) 45 At-Rest Earth Pressure (Cantilever Shoring) (psf) (C) 66 Passive earth pressure (psf per foot of depth) (D) 200
Maximum allowable bearing pressure against native soils (psf) (E) 3,500 Coefficient of friction between sheet pile and native soils, fs (F) 0.25 * Parameters A through F are used in Figures No. 4 and 5 below.

Restrained (braced) shoring systems should be designed based on Figure No. 3, Lateral Earth Pressures for Temporary Braced Excavation to support a uniform rectangular lateral earth pressure.

Geotechnical Investigation Report
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Southeast Corner of the Intersection of Potrero Boulevard and Castello Lane City of Beaumont, Riverside County, California
June 23, 2022

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Figure No. 3, Lateral Earth Pressures for Temporary Braced Excavation

Unrestrained (cantilever) design of cantilever shoring consisting of soldier piles spaced at least two diameters on-center or sheet piles, can be based on Figure No. 4, Lateral Earth Pressures on Temporary Cantilever Wall.

Figure No. 4, Lateral Earth Pressures on Temporary Cantilever Wall

The provided pressures assume no hydrostatic pressures. If hydrostatic pressures are allowed to build up, the incremental earth pressures below the ground-water level should be reduced by 50 percent and added to hydrostatic pressure for total lateral pressure.

Note:

All values of height (H) in feet, pressure (P) and surcharge (q) in pounds per square foot (psf).

Total Earth Pressure, P

P = Pq + Pa

Pq = 0.5q - incremental surcharge pressure

Pa = (A)H1 - active earth pressure (Braced walls)

Lateral Pressure Resistance

Pp = (D) H2 ≤ (E) psf - passive earth pressure (on native soils)

µ = (F) - ultimate friction coefficient
between steel sheet piles and soil

Total Earth Pressure, P

P = Pq + Pa, Po

Pq = 0.5q - incremental surcharge pressure

Pa = (B)H1 - active earth pressure (Un-restrained)

Po = (C)H1 - at rest earth pressure (Restrained)

Lateral Pressure Resistance

Pp = (D) H2 ≤ (E) psf - passive earth pressure (on native soils)

µ = (F) - ultimate friction coefficient between steel
sheet piles and soil
Note:

All values of height (H) in feet, pressure (P) and surcharge (q) in pounds per square foot (psf).

Geotechnical Investigation Report
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Passive resistance includes a safety factor of 1.5. The upper 1 foot for passive resistance should be ignored unless the surface is confined by a pavement or slab.

In addition to the lateral earth pressure, surcharge pressures due to miscellaneous loads, such as soil stockpiles, vehicular traffic or construction equipment located adjacent to the shoring, should be included in the design of the shoring. A uniform lateral pressure of 100 psf should be included in the upper 10 feet of the shoring to account for normal vehicular and construction traffic within 10 feet of the trench excavation. As previously mentioned, all shoring should be designed and installed in accordance with state and federal safety regulations.

The contractor should have provisions for soldier pile and sheet pile removal. All voids resulting from removal of shoring should be filled. The method for filling voids should be selected by the contractor, depending on construction conditions, void dimensions and available materials. The acceptable materials, in general, should be non-deleterious, and able to flow into the voids created by shoring removal (e.g., concrete slurry, “pea” gravel, etc.).

Excavations for the proposed pipeline should not extend below a 1:1 horizontal:vertical (H:V) plane extending from the bottom of any existing structures, utility lines or streets.

Any proposed excavation should not cause loss of bearing and/or lateral supports of the existing utilities or streets.

If the excavation extends below a 1:1 (H:V) plane extending from the bottom of the existing structures, utility lines or streets, a maximum of 10 feet of slope face parallel to the existing improvement should be exposed at a time to reduce the potential for instability. Backfill should be accomplished in the shortest period of time and in alternating sections.

12.0 GEOTECHNICAL SERVICES DURING CONSTRUCTION

The project geotechnical consultant should review plans and specifications as the project design progresses. Such review is necessary to identify design elements, assumptions, or new conditions which require revisions or additions to our geotechnical recommendations.

The project geotechnical consultant should be present to observe conditions during construction. Geotechnical observation and testing should be performed as needed to verify compliance with project specifications. Additional geotechnical recommendations may be required based on subsurface conditions encountered during construction.

Geotechnical Investigation Report
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13.0 CLOSURE

This report is prepared for the project described herein and is intended for use solely by Albert A. Webb Associates and their authorized agents to assist in the design and construction of the proposed project. Our findings and recommendations were obtained in accordance with generally accepted professional principles practiced in geotechnical engineering. We make no other warranty, either expressed or implied.

Converse Consultants is not responsible or liable for any claims or damages associated with interpretation of available information provided to others. Field exploration identifies actual soil conditions only at those points where samples are taken, when they are taken.

Data derived through sampling and laboratory testing is extrapolated by Converse employees who render an opinion about the overall soil conditions. Actual conditions in areas not sampled may differ. In the event that changes to the project occur, or additional, relevant information about the project is brought to our attention, the recommendations contained in this report may not be valid unless these changes and additional relevant information are reviewed, and the recommendations of this report are modified or verified in writing. In addition, the recommendations can only be finalized by observing actual subsurface conditions revealed during construction. Converse cannot be held responsible for misinterpretation or changes to our recommendations made by others during construction.

As the project evolves, continued consultation and construction monitoring by a qualified geotechnical consultant should be considered an extension of geotechnical investigation services performed to date. The geotechnical consultant should review plans and specifications to verify that the recommendations presented herein have been appropriately interpreted, and that the design assumptions used in this report are valid.

Where significant design changes occur, Converse may be required to augment or modify the recommendations presented herein. Subsurface conditions may differ in some locations from those encountered in the explorations, and may require additional analyses and, possibly, modified recommendations.

Design recommendations given in this report are based on the assumption that it will be implemented. Additional consultation may be prudent to interpret Converse's findings for contractors, or to possibly refine these recommendations based upon the review of the actual site conditions encountered during construction. If the scope of the project changes, if project completion is to be delayed, or if the report is to be used for another purpose, this office should be consulted.

Geotechnical Investigation Report
Mesa Lift Station Upgrades
Southeast Corner of the Intersection of Potrero Boulevard and Castello Lane City of Beaumont, Riverside County, California
June 23, 2022

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14.0 REFERENCES

AMERICAN CONCRETE INSTITUTE (ACI), 2014, Building Code Requirements for Structural Concrete (ACI 318-14) and Commentary, October 2014.

AMERICAN SOCIETY OF CIVIL ENGINEERS (ASCE), 2017, Minimum Design Loads for Buildings and Other Structures, SEI/ASCE Standard No. 7-16, dated 2017.

CALIFORNIA BUILDING STANDARDS COMMISSION (CBSC), 2019, California Building Code (CBC).

CALIFORNIA DEPARTMENT OF WATER RESOURCES (DWR), 2022, Water Data Library ( http://wdl.water.ca.gov/waterdatalibrary/) , accessed June 2022.

CALIFORNIA GEOLOGICAL SURVEY (CGS), 2007, Fault-Rupture Hazard Zones in California, Alquist-Priolo Earthquake Faulting Zoning Act with Index to Earthquake Fault Zone Maps, Special Publication 42, revised 2007.

CALIFORNIA STATE WATER RESOURCES CONTROL BOARD (SWRCB), 2022, GeoTracker database ( http://geotracker.waterboards.ca.gov/) , accessed June 2022.

DAS, B.M., 2011, Principles of Foundation Engineering, Seventh Edition, published by Global Engineering, 2011.

DEPARTMENT OF WATER RESOURCES - DIVISION OF SAFETY OF DAMS (DSOD), 2022, California Dam Breach Inundation Maps,
( https://fmds.water.ca.gov/webgis/?appid=dam_prototype_v2) , accessed June 2022.

MATTI, J.C., MORTON, D.M. and LANGANHEIM, V.E., 2015 Geologic and Geophysical Maps of the El Casco 7.5′ quadrangle, Riverside County, Southern California, with accompanying geologic-map database, California, U.S Geologic Survey Open-File Report OF-2010-1274, scale 1:24000

ROMANOFF, MELVIN, 1957, Underground Corrosion, National Bureau of Standards Circular 579, dated April 1957.

U.S. GEOLOGICAL SURVEY (USGS), 2022, National Water Information System: Web Interface ( http://nwis.waterdata.usga.gov/nwis/gwlevels) , accessed June 2022.

U.S. GEOLOGIC SURVEY, 2008 National Seismic Hazard Maps – Source Parameters, https://earthquake.usgs.gov/cfusion/hazfaults_2008_search .

Appendix A
Field Exploration

Geotechnical Investigation Report
Mesa Lift Station Upgrades
Southeast Corner of the Intersection of Potrero Boulevard and Castello Lane City of Beaumont, Riverside County, California
June 23, 2022
Page A-1

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APPENDIX A

FIELD EXPLORATION

Our field investigation included a site reconnaissance and a subsurface exploration program consisting of drilling soil borings. During the site reconnaissance, the surface conditions were noted, and the borings were marked at the locations approved by Bradley Sackett with Albert A. Webb Associates. The approximate boring locations were established in the field with reference to existing landmarks and other visible features.

The locations should be considered accurate only to the degree implied by the method used.

Two exploratory borings (BH-01 and BH-02) were drilled on April 21, 2022, to investigate the subsurface conditions at the site. The borings were drilled to the depths of 20.5 and 51.5 below existing ground surface (bgs).

The borings were advanced using a truck-mounted drill rig equipped with 8-inch diameter hollow-stem augers for soils sampling. Encountered materials were continuously logged by a Converse Engineer and classified in the field by visual classification in accordance with the Unified Soil Classification System. Where appropriate, the field descriptions and classifications have been modified to reflect laboratory test results.

Relatively undisturbed samples were obtained using California Modified Samplers (2.4 inches inside diameter and 3.0 inches outside diameter) lined with thin sample rings. The steel ring sampler was driven into the bottom of the borehole with successive drops of a 140-pound driving weight falling 30 inches. Blow counts at each sample interval are presented on the boring logs. Samples were retained in brass rings (2.4 inches inside diameter and 1.0 inch in height) and carefully sealed in waterproof plastic containers for shipment to the Converse laboratory. Bulk samples of typical soil types were also obtained.

Standard Penetration Testing (SPT) was also performed in accordance with the ASTM Standard D1586 test method at 10-foot intervals beginning at 20 feet bgs in the 50 feet deep boring using a standard (1.4 inches inside diameter and 2.0 inches outside diameter) split-barrel sampler. The mechanically driven hammer for the SPT sampler was 140 pounds, falling 30 inches for each blow. The recorded blow counts for every 6 inches for a total of 1.5 feet of sampler penetration are shown on the Logs of Boring.

The exact depths at which material changes occur cannot always be established accurately. Unless a more precise depth can be established by other means, changes in material conditions that occur between drive samples are indicated on the logs at the top of the next drive sample.

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Following the completion of logging and sampling, the borings were backfilled with soil cuttings mixed with cement and compacted by pushing down with augers using the drill rig weight. If construction is delayed, the surface of the borings may settle over time. We recommend the owner monitor the boring locations and backfill any depression that might occur or provide protection around the boring locations to prevent trip and fall injuries from occurring near the area of any potential settlement.

For a key to soil symbols and terminology used in the borings log, refer to Drawing No. A- 1a and A-1b, Unified Soil Classification and Key to Boring Log Symbols. For logs of borings, see Drawing Nos. A-2a, A-2b and A-3, Logs of Boring.

1 (LITTLE OR NO FINES)

INORGANIC SILTS AND VERY

FINE SANDS, ROCK FLOUR,

SILTY OR CLAYEY FINE

SANDS OR CLAYEY SILTS

WITH SLIGHT PLASTICITY

LIQUID LIMIT LESS
THAN 50

SILTY GRAVELS, GRAVEL - SAND
- SILT MIXTURES
OH
SC

SILTS AND
CLAYS
MORE THAN 50% OF

COARSE FRACTION
PASSING ON NO. 4
SIEVE
MORE THAN 50% OF

MATERIAL IS
LARGER THAN NO.
200 SIEVE SIZE

SILTY SANDS, SAND - SILT

MIXTURES

POORLY-GRADED SANDS,

GRAVELLY SAND, LITTLE OR

NO FINES
(LITTLE OR NO FINES)
OL

WELL-GRADED GRAVELS,

GRAVEL - SAND MIXTURES,

LITTLE OR NO FINES

SANDS WITH
FINES
CL

HIGHLY ORGANIC SOILS PT
MORE THAN 50% OF

MATERIAL IS
SMALLER THAN NO.
200 SIEVE SIZE
SM

WELL-GRADED SANDS,

GRAVELLY SANDS, LITTLE

OR NO FINES
(APPRECIABLE AMOUNT

OF FINES)
SP
SW
COARSE

GRAINED
SOILS

POORLY-GRADED GRAVELS,

GRAVEL - SAND MIXTURES,

LITTLE OR NO FINES

CLAYEY GRAVELS, GRAVEL -

SAND - CLAY MIXTURES

SAMPLE TYPE
LETTER

INORGANIC CLAYS OF LOW TO

MEDIUM PLASTICITY,

GRAVELLY CLAYS, SANDY

CLAYS, SILTY CLAYS, LEAN
CLAYS

ORGANIC CLAYS OF MEDIUM TO

HIGH PLASTICITY, ORGANIC
SILTS
SAND
AND
SANDY
SOILS

INORGANIC SILTS, MICACEOUS

OR DIATOMACEOUS FINE

SAND OR SILTY SOILS

SOIL CLASSIFICATION CHART
MORE THAN 50% OF

COARSE FRACTION
RETAINED ON NO. 4
SIEVE
(APPRECIABLE AMOUNT

OF FINES)
GC

DESCRIPTIONS

BORING LOG SYMBOLS
NOTE: DUAL SYMBOLS ARE USED TO INDICATE BORDERLINE SOIL CLASSIFICATIONS

ORGANIC SILTS AND ORGANIC

SILTY CLAYS OF LOW

PLASTICITY
FINE

GRAINED
SOILS

SILTS AND
CLAYS
ML

TYPICAL
Split barrel sampler in accordance withASTM D-1586-84 Standard Test Method No recovery

BULK SAMPLE

GROUNDWATER WHILE DRILLING

GROUNDWATER AFTER DRILLING
MH
GM
GW

SYMBOLS

PEAT, HUMUS, SWAMP SOILS

WITH HIGH ORGANIC

CONTENTS

LIQUID LIMIT
GREATER THAN 50

MAJOR DIVISIONS

STANDARD PENETRATION TEST
CH

GRAVELS
WITH
FINES
DRIVE SAMPLE 2.42" I.D. sampler (CMS).

DRIVE SAMPLE
CLEAN
SANDS
GRAVEL
AND

GRAVELLY
SOILS
CLEAN

GRAVELS

INORGANIC CLAYS OF HIGH

PLASTICITY
GP

CLAYEY SANDS, SAND - CLAY

MIXTURES
GRAPH
Converse Consultants

DRILLING METHOD SYMBOLS
C
CL
CP
CR
CU
DS
EI
M
OC
P
PA
PI
PL
PM
PP
R
SE
SG
SW
TV
UC
UU
UW

FIELD AND LABORATORY TESTS
Consolidation (ASTM D 2435)
Collapse Potential (ASTM D 4546)
Compaction Curve (ASTM D 1557)
Corrosion, Sulfates, Chlorides (CTM 643-99; 417; 422)
Consolidated Undrained Triaxial (ASTM D 4767)
Direct Shear (ASTM D 3080)
Expansion Index (ASTM D 4829)
Moisture Content (ASTM D 2216)
Organic Content (ASTM D 2974)
Permeablility (ASTM D 2434)
Particle Size Analysis (ASTM D 6913 [2002])
Liquid Limit, Plastic Limit, Plasticity Index
(ASTM D 4318)
Point Load Index (ASTM D 5731)
Pressure Meter
Pocket Penetrometer
R-Value (CTM 301)
Sand Equivalent (ASTM D 2419)
Specific Gravity (ASTM D 854)
Swell Potential (ASTM D 4546)
Pocket Torvane
Unconfined Compression - Soil (ASTM D 2166)
Unconfined Compression - Rock (ASTM D 7012)
Unconsolidated Undrained Triaxial (ASTM D 2850)
Unit Weight (ASTM D 2937)
Auger Drilling Mud Rotary Drilling Dynamic Coneor Hand Driven Diamond Core

UNIFIED SOIL CLASSIFICATION AND KEY TO BORING LOG SYMBOLS Project ID: 21-81-213-01.GPX; Template: KEY
Project No. Drawing No.
21-81-289-01 A-1aMesa Lift Station Upgrades
Southeast of the intersection of Potrero Blvd. and Castello Ln.

City of Beaumont, Riverside County, California
For: Albert Webb Associates

CONSISTENCY OF COHESIVE SOILS
Descriptor
Very Soft
Soft
Medium Stiff
Stiff
Very Stiff
Hard

APPARENT DENSITY OF COHESIONLESS SOILS
Descriptor Criteria
Descriptor SPT N - Value (blows / foot)
Very Loose
Loose
Medium Dense
Dense
Very Dense
50 Nonplastic
Low
Medium
High
Descriptor Criteria
Crumbles or breaks with handling orlittle finger pressure.

Crumbles or breaks with considerable
finger pressure.

Will not crumble or break with fingerpressure.

Weak
Moderate
Strong
Unconfined Compressive Strength (tsf)Torvane (tsf)
Pocket Penetrometer (tsf)

4.0 Descriptor Criteria
Trace (fine)/
Few
Little
Some
Mostly
Particles are present but estimated
to be less than 5%
5 to 10%
15 to 25%
30 to 45%
50 to 100%

PERCENT OF PROPORTION OF SOILS

MOISTURE
Criteria
Absence of moisture, dusty, dry to the touch
Damp but no visible water
Visible free water, usually soil is belowwater table
Size
Coarse
MediumFine
> 12 inches
3 to 12 inches
Passing No. 200 Sieve
No. 10 Sieve to No. 4 Sieve
No. 40 Sieve to No. 10 SieveNo. 200 Sieve to No. No. 40 Sieve

4.0 60

PLASTICITY OF FINE-GRAINED SOILS
Descriptor
Dry
Moist
Wet
Boulder
Cobble
Gravel
Sand
Silt and Clay
Descriptor
Coarse
Fine
3/4 inch to 3 inches
No. 4 Sieve to 3/4 inch
CEMENTATION/ Induration
A 1/8-inch thread cannot be rolled at any water content.

The thread can barely be rolled, and the lump cannot be formed when drier than the plastic limit.

The thread is easy to roll, and not much time is required to reach the plastic limit; it cannot be rerolled after reaching the plastic limit. The lump crumbles when drier than the plastic limit.

It takes considerable time rolling and kneading to reach the plastic limit. The thread can be rerolled several timesafter reaching the plastic limit. The lump can be formed without crumbling when drier than the plastic limit.

Field Approximation
Easily penetrated several inches by fist
Easily penetrated several inches by thumb
Can be penetrated several inches by thumb
with moderate effort
Readily indented by thumb but penetratedonly with great effort Readily indented by thumbnail
Indented by thumbnail with difficulty

2.0 SOIL PARTICLE SIZE
NOTE: This legend sheet provides descriptions andassociated criteria for required soil description componentsonly. Refer to Caltrans Soil and Rock Logging, Classification,and Presentation Manual (2010), Section 2, for tables ofadditional soil description components and discussion of soildescription and identification.

Project ID: Template: KEY
Converse Consultants

UNIFIED SOIL CLASSIFICATION AND KEY TO BORING LOG SYMBOLS SPT Blow
Counts
30 CA
Sampler
50 CA Sampler
60 Scattered (coarse)
21-81-213-01.GPX;
Project No. Drawing No.
21-81-289-01 A-1b
Mesa Lift Station Upgrades
Southeast of the intersection of Potrero Blvd. and Castello Ln.

City of Beaumont, Riverside County, California
For: Albert Webb AssociatesPage 1152 of 1492

ALLUVIUM:

SILTY SAND (SM): fine to coarse-grained, very dense,
few gravel up to 1" in maximum dimension, moist,
brown.
- tace clay
SILTY SAND WITH GRAVEL (SM): fine to
coarse-grained, very dense, some gravel up to 1" in
maximum dimension, moist, brown.
10 9
7 9
10 10
9 4
128
132
130
121
120
134
19/28/39
19/36/44
17/25/34
25/30/33
12/16/23
6/11/17
25/40/50-5"
13/22/34
CR, EI
CL
C, DS
CP, PA
PA
PA
A-2a
Drawing No.

SAMPLES
Gr
a
p
h
i
c
Lo
g
Mahmoud Suliman Hashmi Quazi
BL
O
W
S
DR
Y

U
N
I
T

W
T
.
(p
c
f
)

SUMMARY OF SUBSURFACE CONDITIONS
Checked By:

De
p
t
h

(
f
t
)
Equipment:

MO
I
S
T
U
R
E

(
%
)
Logged by:

Depth to Water (ft, bgs):2424
21-81-289-01

SUMMARY OF SUBSURFACE CONDITIONS
De
p
t
h

(
f
t
)
OT
H
E
R
5 10
15 20
25 30
Mesa Lift Station Upgrades
Southeast of the intersection of Potrero Blvd. and Castello Ln.

City of Beaumont, Riverside County, California
For: Albert Webb Associates
This log is part of the report prepared by Converse for this project and should be read together with the report. This summary applies only at the location of the Boring and at the time of drilling.

Subsurface conditions may differ at other locations and may change at this location with the passage of time. The data presented is a simplification of actual conditions encountered.DR
I
V
E
Project No.

NOT ENCOUNTERED
Log of Boring No. BH-01
Driving Weight and Drop:
4/21/2022
140 lbs / 30 in
BU
L
K
Dates Drilled:
8" HOLLOW STEM AUGER
Ground Surface Elevation (ft):

Gr
a
p
h
i
c
Lo
g
Converse Consultants
Project ID: 21-81-289-01.GPJ; Template: LOG Page 1153 of 1492

ALLUVIUM:

CLAYEY SAND (SC): fine to medium-grained sand,
very dense, moist, brown.

SAND WITH SILT (SP-SM): fine to coarse-grained, very
dense, moist, yellowish brown.

SILTY SAND (SM): fine to coarse-grained, very dense,
few gravel up to 1" in maximum dimension, moist,
brown.
9 6
22 17
106
85 25/48/50-5"
14/20/27
34/50-5"
11/17/27
End of boring at 51.5 feet bgs.

No groundwater encountered.

Borehole backfilled with soil cuttings mixed with cement, compacted by pushing down with augers using drill rig
weight and the surface patched with cold asphalt on
4/21/2022.

A-2b
Drawing No.

SAMPLES
Gr
a
p
h
i
c
Lo
g
Mahmoud Suliman Hashmi Quazi
BL
O
W
S
DR
Y

U
N
I
T

W
T
.
(p
c
f
)

SUMMARY OF SUBSURFACE CONDITIONS
Checked By:

De
p
t
h

(
f
t
)
Equipment:

MO
I
S
T
U
R
E

(
%
)
Logged by:

Depth to Water (ft, bgs):2424
21-81-289-01

SUMMARY OF SUBSURFACE CONDITIONS
De
p
t
h

(
f
t
)
OT
H
E
R
40 45
50 Mesa Lift Station Upgrades
Southeast of the intersection of Potrero Blvd. and Castello Ln.

City of Beaumont, Riverside County, California
For: Albert Webb Associates
This log is part of the report prepared by Converse for this project and should be read together with the report. This summary applies only at the location of the Boring and at the time of drilling.

Subsurface conditions may differ at other locations and may change at this location with the passage of time. The data presented is a simplification of actual conditions encountered.DR
I
V
E
Project No.

NOT ENCOUNTERED
Log of Boring No. BH-01
Driving Weight and Drop:
4/21/2022
140 lbs / 30 in
BU
L
K
Dates Drilled:
8" HOLLOW STEM AUGER
Ground Surface Elevation (ft):

Gr
a
p
h
i
c
Lo
g
Converse Consultants
Project ID: 21-81-289-01.GPJ; Template: LOG Page 1154 of 1492

ALLUVIUM:

SILTY SAND (SM) (SM): fine to coarse-grained, very
dense, moist, reddish-brown.
- trace clay
- few gravel up to 0.5" in maximum dimension
- dense
SAND WITH SILT (SP-SM): fine to coarse-grained, very
dense, moist, yellowish brown.
8 10
11 5
8 116
126
126
122
126
30/48/48
17/25/41
17/25/42
25/27/32
18/20/29
50-5"

CP, PA,
R
CR
DS
dist.

End of boring at 21.5 feet bgs.

No groundwater encountered.

Borehole backfilled with soil cuttings mixed with cement, compacted by pushing down with augers using drill rig
weight and the surface patched with cold asphalt on
4/21/2022.

A-3
Drawing No.

SAMPLES
Gr
a
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Mahmoud Suliman Hashmi Quazi
BL
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DR
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U
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W
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(p
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)

SUMMARY OF SUBSURFACE CONDITIONS
Checked By:

De
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(
f
t
)
Equipment:

MO
I
S
T
U
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(
%
)
Logged by:

Depth to Water (ft, bgs):2424
21-81-289-01

SUMMARY OF SUBSURFACE CONDITIONS
De
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(
f
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)
OT
H
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5 10
15 20
Mesa Lift Station Upgrades
Southeast of the intersection of Potrero Blvd. and Castello Ln.

City of Beaumont, Riverside County, California
For: Albert Webb Associates
This log is part of the report prepared by Converse for this project and should be read together with the report. This summary applies only at the location of the Boring and at the time of drilling.

Subsurface conditions may differ at other locations and may change at this location with the passage of time. The data presented is a simplification of actual conditions encountered.DR
I
V
E
Project No.

NOT ENCOUNTERED
Log of Boring No. BH-02
Driving Weight and Drop:
4/21/2022
140 lbs / 30 in
BU
L
K
Dates Drilled:
8" HOLLOW STEM AUGER
Ground Surface Elevation (ft):

Gr
a
p
h
i
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Lo
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Converse Consultants
Project ID: 21-81-289-01.GPJ; Template: LOG Page 1155 of 1492

Appendix B
Laboratory Testing Program

Geotechnical Investigation Report
Mesa Lift Station Upgrades
Southeast Corner of the Intersection of Potrero Boulevard and Castello Lane City of Beaumont, Riverside County, California
June 23, 2022
Page B-1

Converse Consultants
M:\JOBFILE\2021\81\21-81-289 Webb, Mesa Lift Station & Force Main\Report\21-81-131_GIR(01)booste

APPENDIX B

LABORATORY TESTING PROGRAM

Tests were conducted in our laboratory on representative soil samples for the purpose of classification and evaluation of their physical properties and engineering characteristics.

The amount and selection of tests were based on the geotechnical parameters required for this project. Test results are presented herein and on the Logs of Borings, in Appendix A, Field Exploration. The following is a summary of the various laboratory tests conducted for this project.

In-Situ Moisture Content and Dry Density
In-situ dry density and moisture content tests were performed on relatively undisturbed ring samples, in accordance with ASTM Standard D2216 and D2937 to aid soils classification and to provide qualitative information on strength and compressibility characteristics of the site soils. For test results, see the Logs of Borings in Appendix A, Field Exploration.

Expansion Index
Two representative bulk samples were tested to evaluate the expansion potential in accordance with ASTM Standard D4829. The test results are presented in the following table.

Table No. B-1, Expansion Index Test Result

R-value
One representative bulk soil sample was performed by AP Engineering and Testing, Inc. (Pomona, CA) in accordance with California Test Method CT301 for resistance value (R- value). The test provides a relative measure of soil strength for use in pavement design.

The test results are presented in the following table.

Table No. B-2, R-Value Test Results
Boring No. Depth (feet) Soil Classification Measured R-value BH-02 0-5 Silty Sand (SM) 36

Boring No. Depth
(feet) Soil Description Expansion Index Expansion Potential BH-01 0-5 Silty Sand (SM) 0 Very Low
BH-02 0-5 Silty Sand (SM) 16 Very Low

Geotechnical Investigation Report
Mesa Lift Station Upgrades
Southeast Corner of the Intersection of Potrero Boulevard and Castello Lane City of Beaumont, Riverside County, California
June 23, 2022
Page B-2

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Soil Corrosivity
Two representative soil samples were tested to determine minimum electrical resistivity, pH, and chemical content, including soluble sulfate and chloride concentrations. The purpose of these tests was to determine the corrosion potential of site soils when placed in contact with common construction materials. The tests were performed by AP Engineering and Testing, Inc. (Pomona, CA) in accordance with Caltrans Test Methods 643, 422 and 417. Test results are presented in the following table.

Table No. B-3, Summary of Soil Corrosivity Test Results Boring No. Depth
(feet) pH
Soluble Sulfates
(CA 417)
(ppm)
Soluble
Chlorides
(CA 422) (ppm)
Min. Resistivity
(CA 643)
(Ohm-cm)
BH-01 0-5 8.5 39 21 4,093
BH-02 5-10 8.7 32 20 4,232

Collapse
To evaluate the moisture sensitivity (collapse/swell potential) of the encountered soils, two collapse tests were performed in accordance with the ASTM Standard D4546 laboratory procedure. The samples were loaded to approximately 2 kips per square foot (ksf), allowed to stabilize under load, and then submerged. The tests results are presented in the following table.

Table No. B-4, Collapse Test Results
Boring
No. Depth (ft) Soil Classification Percent Swell (+)
Percent Collapse (-)
Collapse
Potential
BH-01 2.5-4.0 Silty Sand (SM) -0.7 Slight
BH-01 5.0-6.5 Silty Sand (SM) -1.0 Slight

Grain-Size Analysis
To assist in classification of soils, mechanical grain-size analyses were performed on four select samples in accordance with the ASTM Standard D6913 test method. Grain-size curves are shown in Drawing No. B-1, Grain Size Distribution Results and results are presented in the below table.

Table No. B-5, Grain Size Distribution Test Results
Boring No. Depth (ft) Soil Classification % Gravel % Sand %Silt %Clay BH-01 5-10 Silty Sand (SM) 9.0 63.5 27.5
BH-01 20.0-21.5 Silty Sand with Gravel (SM) 21.0 54.2 24.8 BH-01 30.0-31.5 Silty Sand with Gravel (SM) 15.0 69.6 15.4 BH-02 0-5 Silty Sand (SM) 12.0 59.3 28.7

Geotechnical Investigation Report
Mesa Lift Station Upgrades
Southeast Corner of the Intersection of Potrero Boulevard and Castello Lane City of Beaumont, Riverside County, California
June 23, 2022
Page B-3

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Maximum Density and Optimum Moisture Content
Laboratory maximum dry density-optimum moisture content relationship tests were performed on two representative bulk samples. The tests were conducted in accordance with the ASTM Standard D1557 test method. The tests results are presented in Drawing No. B-2, Moisture-Density Relationship Results, and are summarized in the following table.

Table No B-6, Summary of Moisture-Density Relationship Results Boring No. Depth (ft) Soil Description Optimum
Moisture (%)
Maximum
Density (lb./cft)
BH-01 5-10 Silty Sand (SM), Yellowish
Brown 9.2 133.5
BH-02 0-5 Silty Sand (SM), Yellowish
Brown 9.0 129.0

Direct Shear
Two direct shear tests were performed on relatively undisturbed representative ring samples under soaked moisture condition in accordance with the ASTM D3080 procedure. For the test, three samples contained in brass sampler rings were placed, one at a time, directly into the test apparatus and subjected to a range of normal loads appropriate for the anticipated conditions. The samples were then sheared at a constant strain rate of 0.02 inch/minute. Shear deformation was recorded until a maximum of about

0.25-inch shear displacement was achieved. Ultimate strength was selected from the shear-stress deformation data and plotted to determine the shear strength parameters.

For test data, including sample density and moisture content, see Drawings No. B-3 and B-4, Direct Shear Test Results, and the following table.

Table No. B-7, Summary of Direct Shear Test Results
Boring No.

Depth
(feet) Soil Description
Peak Strength Parameters
Friction Angle
(degrees)
Cohesion
(psf)
BH-01 5.0-6.5 Silty Sand (SM) 33 80
BH-02 7.5-9.0 Silty Sand (SM) 34 20

Consolidation
One test was conducted in accordance with ASTM Standard D2435 method. Data obtained from this test on a relatively undisturbed ring sample was used to evaluate the settlement characteristics of the on-site soils under load. Preparation for this test involved trimming the sample, placing it in a 1-inch-high brass ring, and loading it into the test apparatus, which contained porous stones to accommodate drainage during testing. Normal axial loads were applied to one end of the sample through the porous stones, and the resulting deflections were recorded at various time periods. The load was increased after the sample reached a

Geotechnical Investigation Report
Mesa Lift Station Upgrades
Southeast Corner of the Intersection of Potrero Boulevard and Castello Lane City of Beaumont, Riverside County, California
June 23, 2022
Page B-4

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reasonable state of equilibrium. Normal loads were applied at a constant load-increment ratio, successive loads being generally twice the preceding load. For test result, including sample density and moisture content, see Drawing No. B-5 Consolidation Test Result.

Sample Storage
Soil samples presently stored in our laboratory will be discarded 30 days after the date of this report, unless this office receives a specific request to retain the samples for a longer period.

0 5
10 15
20 25
30 35
40 45
50 55
60 65
70 75
80 85
90 95
100

0.0010.010.1110100
4 200
Drawing No.

PE
R
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E
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F
I
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B
Y

W
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G
H
T
100

GRAIN SIZE DISTRIBUTION RESULTS
coarse
6 5020
%Gravel
Description PI Cc
mediumfine

0.6 0.111

0.238

0.378
Depth (ft) D100 %Sand %Clay
4 U.S. SIEVE OPENING IN INCHES
coarse
2 SILTY SAND (SM)

SILTY SAND WITH GRAVEL (SM)

SILTY SAND WITH GRAVEL (SM)

SILTY SAND (SM)
Depth (ft)Cu
1413

SILT OR CLAY
U.S. SIEVE NUMBERS
3/8
GRAVEL
140

COBBLES
Project No.
5-10
20-21.5

30.0-31.5
5-10
D10 %Silt
Boring No.PL
21-81-289-01 B-1
10 BH-01
BH-01
BH-01
BH-02
BH-01
BH-01
BH-01
BH-02

63.5 54.2

69.6 59.3

1.298

0.647

1.009

1.743
5-10
20-21.5

30.0-31.5
5-10
Mesa Lift Station Upgrades
Southeast of the intersection of Potrero Blvd. and Castello Ln.

City of Beaumont, Riverside County, California
For: Albert Webb Associates
6 30 403

HYDROMETER

27.5 24.8

15.4 28.7
D30
SAND
19 19
25 19
Boring No.D60
LL

9.0 21.0

15.0 12.0
1683/4

GRAIN SIZE IN MILLIMETERS

1.5 1/2
fine
60 Project ID: 21-81-289-01.GPJ; Template: GRAIN SIZE
Converse Consultants

90 95
100
105
110
115
120
125
130
135
140
145
150
0 5 10 15 20 25 30
DR
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D
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p
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MOISTURE-DENSITY RELATIONSHIP RESULTS
B-2
Drawing No.

2.80 2.70

2.60 9.2

9.0 WATER CONTENT, %
DEPTH (ft) DESCRIPTION
ASTM

TEST METHOD

OPTIMUM
WATER, %

MAXIMUM DRY
DENSITY, pcf
BH-01
BH-02
133.5
129.0
5-10
0-5
Curves of 100% Saturation
for Specific Gravity Equal to:

Project No.
21-81-289-01
SYMBOL BORING NO.

SILTY SAND (SM), BROWN

SILTY SAND (SM), REDDISH BROWN
Mesa Lift Station Upgrades
Southeast of the intersection of Potrero Blvd. and Castello Ln.

City of Beaumont, Riverside County, California
For: Albert Webb Associates
Project ID: 21-81-289-01.GPJ; Template: COMPACTION
Converse Consultants

0 500
1,000
1,500
2,000
2,500
3,000
3,500
4,000
0 1,000 2,000 3,000 4,000
DESCRIPTION :

SURCHARGE PRESSURE, psf
33:

Project No.
21-81-289-01
:
:

5.0-6.5
DRY DENSITY (pcf)

DIRECT SHEAR TEST RESULTS
:BORING NO.

SILTY SAND (SM)
B-3
:9.0
70 132.5
Drawing No.

COHESION (psf)
BH-01
NOTE: Ultimate Strength.

DEPTH (ft)
MOISTURE CONTENT (%)
SH
E
A
R

S
T
R
E
N
G
T
H
,

p
s
f
FRICTION ANGLE (degrees)
:

Mesa Lift Station Upgrades
Southeast of the intersection of Potrero Blvd. and Castello Ln.

City of Beaumont, Riverside County, California
For: Albert Webb Associates
Converse Consultants
Project ID: 21-81-289-01.GPJ; Template: DIRECT SHEAR Page 1163 of 1492

0 500
1,000
1,500
2,000
2,500
3,000
3,500
4,000
0 1,000 2,000 3,000 4,000
DESCRIPTION :

SURCHARGE PRESSURE, psf
34:

Project No.
21-81-289-01
:
:

7.5-9.0
DRY DENSITY (pcf)

DIRECT SHEAR TEST RESULTS
:BORING NO.

SILTY SAND (SM)
B-4
:11.0
20 126.4
Drawing No.

COHESION (psf)
BH-02
NOTE: Ultimate Strength.

DEPTH (ft)
MOISTURE CONTENT (%)
SH
E
A
R

S
T
R
E
N
G
T
H
,

p
s
f
FRICTION ANGLE (degrees)
:

Mesa Lift Station Upgrades
Southeast of the intersection of Potrero Blvd. and Castello Ln.

City of Beaumont, Riverside County, California
For: Albert Webb Associates
Converse Consultants
Project ID: 21-81-289-01.GPJ; Template: DIRECT SHEAR Page 1164 of 1492

0 2
4 6
8 10
100 1,000 10,000 105
NOTE: SOLID CIRCLES INDICATE READINGS AFTER ADDITION OF WATER

MOISTURE
CONTENT (%)

DRY DENSITY
(pcf)
BH-01BORING NO.

SILTY SAND (SM)
Project No.
21-81-289-01
VOID
RATIO
DEPTH (ft)

CONSOLIDATION TEST RESULTS

INITIAL
Drawing No.

DESCRIPTION :
:

B-5
STRESS, psf
9 PERCENT

SATURATION
ST
R
A
I
N
,

%

0.251
:5.0-6.5
132 94
Mesa Lift Station Upgrades
Southeast of the intersection of Potrero Blvd. and Castello Ln.

City of Beaumont, Riverside County, California
For: Albert Webb Associates
Project ID: 21-81-289-01.GPJ; Template: CONSOLIDATION
Converse Consultants

Appendix C
Liquefaction & Seismic Settlement Analysis

Geotechnical Investigation Report
Mesa Lift Station Upgrades
Southeast Corner of the Intersection of Potrero Boulevard and Castello Lane City of Beaumont, Riverside County, California
June 23, 2022
Page C-1

Converse Consultants
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APPENDIX C

LIQUEFACTION AND SEISMIC SETTLEMENT ANALYSIS

The subsurface data obtained from the boring BH-02 was used to evaluate the liquefaction potential and associated dry seismic settlement when subjected to ground shaking during earthquakes.

A simplified liquefaction hazard analysis was performed using the program SPTLIQ (InfraGEO Software, 2020) using the liquefaction triggering analysis method by Boulanger and Idriss (2014). A modal earthquake magnitude of M 8.1 was selected based on the results of seismic deaggregation analysis using the USGS interactive online tool ( https://earthquake.usgs.gov/hazards/interactive/) .

A peak ground acceleration (PGAM) of 0.74g for the MCE design event, where g is the acceleration due to gravity, was selected for this analysis. The PGA was based on the 2019 CBC seismic design parameters presented in Section 7.3.2, Site-Specific Seismic Design Parameters. The result of our analysis is presented on Sheet Nos. C-1 through C-3 and summarized in the following table.

Table C-1, Estimated Dynamic Settlements
Location Groundwater
Conditions
Groundwater
Depth (feet bgs)
Dry Seismic
Settlement (inches)
Liquefaction
Induced Settlement
(inches)
BH-01
Current >50

0.4 Negligible
Historical >50

Based on our analysis, the potential for liquefaction induced settlement is negligible and dry seismic settlement is up to 0.4 inches.

The soil profile across the site is relatively similar. So, we anticipate that the total dynamic settlement will be uniform. We recommend that the planned structure be designed conservatively in anticipation of dynamic differential settlement of 0.5 inch in 40 horizontal feet.

8.10 0.76

1.20 BH-01
2424.00

52.00 52.00

8.00 140.00

30.00 80.00 %

5.00 TSC1
> 0.00 feet
(feet)(feet)USCS Group Symbol
(ASTM D2487)(pcf)(blows/ft)(%)

0.00 5.00 SM Y 140.0 43.0 SPT1 15.00

5.00 10.00 SM Y 139.0 50.0 SPT1 15.00

10.00 15.00 SM Y 131.0 41.0 SPT1 15.00

15.00 20.00 SM Y 132.0 25.0 SPT1 15.00

20.00 25.00 SM Y 145.0 28.0 SPT1 12.00

25.00 30.00 SP-SM Y 145.0 32.5 SPT1 12.00

30.00 35.00 SM Y 118.0 28.0 SPT1 15.00

35.00 40.00 SC Y 118.0 50.0 SPT1 15.00

40.00 45.00 SP-SM Y 103.0 47.0 SPT1 12.00

45.00 50.00 SM Y 103.0 44.0 SPT1 25.00
Total Soil
Unit Weight
gt
Field SPT
Blow Count
Nfield
Liquefaction
Screening
Susceptible Soil?
(Y, N)

INPUT SOIL PROFILE DATA
Factor of Safety Against Liquefaction, FS
Type of
Soil
Sampler
Material
Type
Depth to
Top of
Soil Layer
Depth to
Bottom of
Soil Layer
Fines
Content
FC
feet
- Ground Slope, S (%)
feet

SELECTED METHODS OF ANALYSIS
Triggering of Liquefaction
Analysis Description
Hashmi Quzai

SIMPLIFIED LIQUEFACTION HAZARDS ASSESSMENT USING STANDARD PENETRATION TEST (SPT) DATA (Copyright © 2015, 2019, SPTLIQ, All Rights Reserved; By: InfraGEO Software)

PROJECT INFORMATION
Project Name Mesa Lift Station Project
21-81-289-01
City of Beaumont, Riverside County, California
Mahmoud Suliman Analyzed By
Project No.

Project Location
Reviewed By
(Level Ground with No Nearby Free Face)
Hammer Distance to Ground Surface
Hammer Energy Efficiency Ratio, ER (%)
GWL Depth Used in Design
Borehole Diameter inches
feet
- Free Face Distance to Slope Height Ratio, (L/H)
<<= Leave this blank
Topographic Site Condition:
inches
g
Hammer Drop
Earthquake Moment Magnitude, Mw
feet
Proposed Grade Elevation
Ground Surface Elevation
Boring No.

BORING DATA AND SITE CONDITIONS
Peak Ground Acceleration, Amax
GWL Depth Measured During Test
pounds Hammer Weight
feet

SEISMIC DESIGN PARAMETERS
Residual Shear Strength of Liquefied Soil
Boulanger-Idriss (2014)
Pradel (1998)
Ishihara and Yoshimine (1992)
Idriss and Boulanger (2008)
LPI: Liquefaction Potential Index based on Iwasaki et al. (1978) Zhang et al. (2004)
Severity of Liquefaction
Seismic Compression Settlement (Dry/Unsaturated Soil)
Liquefaction-Induced Settlement (Saturated Soil)
Liquefaction-Induced Lateral Spreading
SPTLIQcc SPTLIQ Input Data Sheet C-1
2424.00

Severity of Liquefaction:

Total Thickness of Liquefiable Soils: 0.00 feet (cumulative total thickness in the upper 65 feet) Liquefaction Potential Index (LPI):0.00 *** (Very low risk, with no surface manifestation of liquefaction) Seismic Ground Settlements: Upper 30 feet Upper 50 feet Upper 65 feet Seismic Compression Settlement: 0.25 inches 0.40 inches 0.40 inches

8.10 Liquefaction-Induced Settlement:0.00 inches 0.00 inches 0.00 inches

0.76 Total Seismic Settlement:0.25 inches 0.40 inches 0.40 inches

1.20 Seismic Lateral Displacements: Upper 30 feet Upper 50 feet Upper 65 feet Cyclic Lateral Displacement:0.22 inches 0.35 inches 0.35 inches (During Ground Shaking) BH-01 Lateral Spreading Displacement:0.00 inches 0.00 inches 0.00 inches (After Ground Shaking) 2424.00
2424.00

52.00 feet

52.00 feet

8.00 inches
140.00 pounds

30.00 inches

80.00 %

5.00 feet
TSC1

0.00 %
N/A H =
120.00 pcf (assumed)
Depth to
Top of
Soil Layer
Depth to
Bottom of
Soil Layer
Material Type
USCS
Group Symbol
(ASTM D2487)
Liquefaction
Susceptibility
Screening
++
Susceptible
Soil? (Y/N)
Total Soil
Unit
Weight
gt
Field
SPT Blow
Count
Nfield
Type of
Soil
Sampler
Fines
Content
FC
Total
Vert.

Stress
(Design)
svo
Effective
Vert.

Stress
(Design)
s'vo
SPT
Corr.
for
Vert.

Stress
CN
SPT
Corr.
for
Hammer
Energy
CE
SPT
Corr.
for
Borehole
Size
CB
SPT
Corr.
for
Rod
Length
CR
SPT
Corr.
for
Sampling
Method
CS
Corrected
SPT Blow
Count
N60
Normalized
SPT Blow
Count
(N1)60
Fines
Corrected
SPT Blow
Count
(N1)60cs
Shear
Stress
Reduction
Coefficient
rd
Correction
for High
Overburden
Stress
Ks
Cyclic
Stress
Ratio
CSR
Cyclic
Resistance
Ratio
CRR
Factor of
Safety
*
FSliq
Liquefaction
Analysis
Results
(feet)(feet)(pcf)(blows/ft)(%)(psf)(psf)(psf)(%)(inches)(inches)(inches)

0.00 5.00 SM Y 140.00 43.00 SPT1 15.00 350.00 350.00 1.326 1.333 1.150 0.750 1.000 49.5 65.5 68.8 1.000 1.100 0.494 0.40 0.35 0.00

5.00 10.00 SM Y 139.00 50.00 SPT1 15.00 1,047.50 1,047.50 1.103 1.333 1.150 0.800 1.000 61.3 67.7 70.9 0.995 1.100 0.492 0.40 0.35 0.00

10.00 15.00 SM Y 131.00 41.00 SPT1 15.00 1,722.50 1,722.50 1.032 1.333 1.150 0.850 1.000 53.4 55.2 58.4 0.986 1.045 0.487 0.40 0.35 0.00

15.00 20.00 SM Y 132.00 25.00 SPT1 15.00 2,380.00 2,380.00 0.944 1.333 1.150 0.950 1.000 36.4 34.4 37.6 0.976 0.956 0.482 0.40 0.35 0.00

20.00 25.00 SM Y 145.00 28.00 SPT1 12.00 3,072.50 3,072.50 0.869 1.333 1.150 0.950 1.000 40.8 35.4 37.5 0.965 0.871 0.477 0.27 0.24 0.00

25.00 30.00 SP-SM Y 145.00 32.50 SPT1 12.00 3,797.50 3,797.50 0.822 1.333 1.150 0.950 1.000 47.3 38.9 41.0 0.952 0.808 0.470 0.15 0.13 0.00

30.00 35.00 SM Y 118.00 28.00 SPT1 15.00 4,455.00 4,455.00 0.758 1.333 1.150 1.000 1.000 42.9 32.5 35.8 0.939 0.816 0.464 0.15 0.13 0.00

35.00 40.00 SC Y 118.00 50.00 SPT1 15.00 5,045.00 5,045.00 0.863 1.333 1.150 1.000 1.000 76.7 66.2 69.4 0.925 0.722 0.457 0.00 0.00 0.00

40.00 45.00 SP-SM Y 103.00 47.00 SPT1 12.00 5,597.50 5,597.50 0.819 1.333 1.150 1.000 1.000 72.1 59.0 61.1 0.909 0.691 0.449 0.00 0.00 0.00

45.00 50.00 SM Y 103.00 44.00 SPT1 25.00 6,112.50 6,112.50 0.774 1.333 1.150 1.000 1.000 67.5 52.2 57.3 0.894 0.665 0.441 0.00 0.00 0.00 REFERENCES:

1. Boulanger, R.W. and Idriss, I.M. (2014), "CPT and SPT Based Liquefaction Triggering Procedures," University of California Davis, Center for Geotechnical Modeling Report No. UCD/CGM-14/01, 1-134.

2. Bray, J.D., and Sancio, R.B. (2006). "Assessment of the liquefaction susceptibility of fine-grained soils," Journal of Geotechnical and Geoenvironmental Engineering, ASCE 132 (9), 1165-1177.

3. Cetin, K.O. and Seed, R.B., et al. (2004), "Standard penetration test-based probabilistic and deterministic assessment of seismic soil liquefaction potential," Journal of Geotechnical and Geoenvironmental Engineering, ASCE 130 (12), 1314-1340.

4. Idriss, I.M. and Boulanger, R.W. (2008), "Soil Liquefaction During Earthquakes", Earthquake Engineering Research Institute (EERI), Monograph MNO-12.

5. Ishihara, K. and Yoshimine, M. (1992), "Evaluation of settlements in sand deposits following liquefaction during earthquakes," Soils and Foundations, Japanese Geotechnical Society, 32 (1), 173-188.

6. Iwasaki, T., et al. (1978), "A practical method for assessing soil liquefaction potential based on case studies at various sites in Japan," Proceedings Of 3rd International Conference of Microzonation, San Francisco, 885-896.

7. Olson, S.M. and Johnson, C.I. (2008), "Analyzing Liquefaction-Induced Lateral Spreads Using Strength Ratios," Journal of Geotechnical and Geoenvironmental Engineering, ASCE 134 (8), 1035-1049.

8. Pradel, D. (1998), "Procedure to Evaluate Earthquake-Induced Settlements in Dry Sandy Soils," Journal of Geotechnical Engineering, ASCE 124 (4), pp. 364-368.

9. Seed, R.B. and Harder, L.F. (1990), "SPT-based analysis of cyclic pore pressure generation and undrained residual strength, Proceedings Of Seed Memorial Symposium, Vancouver, B.C., 351-376.

10. Tokimatsu, K. and Seed, H.B. (1987), "Evaluation of settlements in sands due to earthquake shaking," Journal of Geotechnical Engineering, ASCE 113 (GT8), 861-878.

11. Tokimatsu, K. and Asaka, Y. (1998), "Effects of liquefaction-induced ground displacementson pile performance in the 1995 Hyogoken-Nambu Earthquake," Soils and Foundations, Special Issue, Japan Geotechnical Society, 163-177.

12. Tonkin & Taylor (2013), "Liquefaction Vulnerability Study," Report prepared for the Earthquake Commission (EQC), February, T&T Report No. 520.20.0200.

13. Toprak, S. and Holzer, T.L. (2003), "Liquefaction Potential Index: Field Assessment," Journal of Geotechnical and Geoenviromental Engineering, ASCE 129 (4), 315-322.

14. Youd, T.L, Idriss, I.M., et al. (2001), "Liquefaction resistance of soils: summary report from the 1996 NCEER and 1998 NCEER/NSF Workshops", Journal of Geotechnical and Geoenvironmental Engineering, ASCE 127 (10), 817-833.

15. Zhang, G, Robertson, P.K. and Brachman, R.W.I. (2004), "Estimating liquefaction-induced lateral displacement using the standard penetration test or cone penetration test," Journal of Geotechnical and Geoenvironmental Engineering, ASCE 130 (8), 861-871. (Dry/Unsaturated Soils)
(Saturated Soils)Ishihara and Yoshimine (1992)

SIMPLIFIED LIQUEFACTION HAZARDS ASSESSMENT USING STANDARD PENETRATION TEST (SPT) DATA (Copyright © 2015, 2019, SPTLIQ, All Rights Reserved; By: InfraGEO Software) Mesa Lift Station Project
Mahmoud Suliman
Hashmi Quzai
Analyzed By
Reviewed By

SUMMARY OF RESULTS
Analysis Method

PROJECT INFORMATION
Project Name
Analysis Method
Tokimatsu and Asaka (1998)
Zhang et al. (2004)
Pradel (1998)
g
feet
21-81-289-01
City of Beaumont, Riverside County, California
Average Total Unit Weight of New Fill

SEISMIC DESIGN PARAMETERS
Earthquake Moment Magnitude, Mw
Borehole Diameter
Hammer Weight
GWL Depth Measured During Test
GWL Depth Used in Design
Boring No.

Ground Surface Elevation
Factor of Safety Against Liquefaction, FS
Project No.

Project Location

BORING DATA AND SITE CONDITIONS
Peak Ground Acceleration, Amax
- Ground Slope, S
Proposed Grade Elevation
Hammer Distance to Ground Surface
Topographic Site Condition:
feet
(Level Ground with No Nearby Free Face)
Hammer Drop
Hammer Energy Efficiency Ratio, ER
+ This method of analysis is based on observed seismic performance of level ground sites using correlation with normalized and fines-corrected SPT blow count, (N1)60cs = f{(N1)60, FC} where (N1)60 = Nfield CN CE CB CR CS * FSliq = Factor of Safety against liquefaction = (CRR/CSR), where CRR = CRR7.5 MSF Ks Ka , MSF = Magnitude Scaling Factor, Ks = f[(N1)60, s'vo], Ka =1.0, (level ground), ++ Liquefaction susceptibility screening is performed to identify soil layers assessed to be non-liquefiable based on laboratory test results using the criteria proposed by Cetin and Seed (2003), Bray and Sancio (2006), or Idriss and Boulanger (2008).

NOTES AND REFERENCES
** Residual strength values of liquefied soils are based on correlation with post-earthquake, normalized and fines-corrected SPT blow count derived by Idriss and Boulanger (2008).

CSR = Cyclic Stress Ratio = 0.65 Amax (svo/s'vo) rd , and CRR7.5 = Cyclic Resistance Ratio is a function of (N1)60cs and corrected for an earthquake magnitude Mw of 7.5. *** Based on Iwasaki et al. (1978) and Toprak and Holzer (2003) INPUT SOIL PROFILE DATA Residual
Shear
Strength
**
Sr
LIQUEFACTION TRIGGERING ANALYSIS BASED ON R.W. BOULANGER AND I.M. IDRISS (2014) METHOD +Cumulative Cyclic
Lateral
Displacement
Cumulative
Lateral
Spreading
Displacement
Seismic
Porewater
Pressure
Ratio
ru
Cumulative
Seismic
Settlement
+ Reference: Boulanger, R.W. and Idriss, I.M. (2014), "CPT and SPT Based Liquefaction Triggering Procedures," University of California Davis, Center for Geotechnical Modeling Report No. UCD/CGM-14/01, 1-134.- Free Face (L/H) Ratio 0 feet SPTLIQcc SPTLIQ Output Sheet C-2

BH-01
2424.00
2424.00

8.00 140.00
Hammer Drop 30.00
Hammer Energy Efficiency Ratio, ER 80.00

0.00 Hammer Distance to Ground Surface 5.00
N/A H =0.00 feet
Earthquake Moment Magnitude, Mw 8.10
GWL Depth Measured During Test 52.00 feet Peak Ground Acceleration, Amax 0.76 g GWL Depth Used in Design 52.00 feet Factor of Safety Against Liquefaction, FS 1.20 Boulanger-Idriss (2014)Above GWL:

Below GWL:

SEISMIC DESIGN PARAMETERS

GROUNDWATER DATA
Reviewed By

BORING DATA
%
Ground Surface Elevation
Proposed Grade Elevation
Mesa Lift Station Project

TOPOGRAPHIC CONDITIONS
Boring No.
21-81-289-01
City of Beaumont, Riverside County, California
Mahmoud Suliman
Hashmi Quzai Hammer Weight
%
Ground Slope, S
Free Face (L/H) Ratio
feet
inches
pounds
feet
feet
inches
Analysis Methods Used ==>>
Project Location
Analyzed By Borehole Diameter
Below GWL:Ishihara and Yoshimine (1992)Tokimatsu and Asaka (1998) Pradel (1998)
Lateral Spreading:Liquefaction Triggering:

SIMPLIFIED LIQUEFACTION HAZARDS ASSESSMENT USING STANDARD PENETRATION TEST (SPT) DATA (Copyright © 2015, 2019, SPTLIQ, All Rights Reserved; By: InfraGEO Software)

PROJECT INFORMATION
Project Name
Project No.

Pradel (1998)
Cyclic Lateral Displacements:Seismic Settlements:

Zhang et al. (2004)Above GWL:
0 5
10 15
20 25
30 35
40 45
50 55
60 65
70 75

0.00 0.25 0.50 0.75 1.00
CSR = Cyclic Stress Ratio;
CRR = Cyclic Resistance Ratio
CSR (Load)
CRR (Resistance)
0 5
10 15
20 25
30 35
40 45
50 55
60 65
70 75

0.00 0.50 1.00 1.50 2.00
Factor of Safety, FS
Required FS
Computed FS
GWL
0 5
10 15
20 25
30 35
40 45
50 55
60 65
70 75
0 25 50 75 100 125
So
i
l

D
e
p
t
h

D
u
r
i
n
g

T
e
s
t

(
f
e
e
t
)
SPT N-values and Fines Content
N60, (N1)60cs ; FC (%)
SPT N60
SPT (N1)60cs
FC (%)
0 5
10 15
20 25
30 35
40 45
50 55
60 65
70 75

0.00 0.10 0.20 0.30 0.40 0.50
Seismic Settlement (in.)
0 5
10 15
20 25
30 35
40 45
50 55
60 65
70 75

0.00 0.10 0.20 0.30 0.40
Cyclic Lateral Disp. (in.)
0 5
10 15
20 25
30 35
40 45
50 55
60 65
70 75

0.00 0.50 1.00
Lateral Spreading (in.)
SPTLIQcc SPTLIQ Output Sheet C-3

Converse Consultants
Geotechnical Engineering, Environmental & Groundwater Science, Inspection & Testing Services

2021 Rancho Drive, Suite 1, Redlands, California 92373
Telephone: (909) 796-0544 ♦ Facsimile: (909) 796-7675 ♦ www.converseconsultants.com

GEOTECHNICAL INVESTIGATION REPORT FOR

THE BRINE DISPOSAL PIPELINE
Cities of Beaumont, Redlands, Loma Linda, and San Bernardino Riverside and San Bernardino Counties, California

Converse Project No. 16-81-255-02

Prepared For:

Albert A. Webb Associates
3788 McCray Street
Riverside, California 92506

Prepared By:

Converse Consultants
2021 Rancho Drive, Suite 1
Redlands, California 92373

May 30, 2017

Converse Consultants
Geotechnical Engineering, Environmental & Groundwater Science, Inspection & Testing Services

2021 Rancho Drive, Suite 1, Redlands, California 92373
Telephone: (909) 796-0544 ♦ Facsimile: (909) 796-7675 ♦ www.converseconsultants.com

May 30, 2017

Mr. Bill Malone, PE
Vice President
Albert A. Webb Associates
3788 McCray Street
Riverside, California 92506

Subject: GEOTECHNICAL INVESTIGATION REPORT FOR THE BRINE DISPOSAL

PIPELINE
Cities of Beaumont, Redlands, Loma Linda, and San Bernardino Riverside and San Bernardino Counties, California
Converse Project No. 16-81-255-02

Dear Mr. Malone:

Converse Consultants (Converse) is pleased to submit this geotechnical investigation report to assist with the preliminary design of the City of Beaumont Public Works Department Brine Disposal Pipeline located within the cities of Beaumont, Redlands, Loma Linda, San Bernardino and Riverside and San Bernardino Counties, California. This report was prepared in accordance with our proposal revised February 10, 2017, and your Task Order Agreement No. 2016-0301-001 dated February 14, 2017.

Based upon our field investigation, laboratory data, and analyses, the proposed pipeline is considered feasible from a geotechnical standpoint, provided the recommendations presented in this report are incorporated into the design and construction of the project.

We appreciate the opportunity to be of service to Albert A. Webb Associates and the City of Beaumont Public Works Department. Should you have any questions, please do not hesitate to contact us at 909-796-0544.

CONVERSE CONSULTANTS
Hashmi Quazi, PhD, GE, PE
Principal Engineer

Dist: 4/Addressee

JB/JR/SM/HSQ

Geotechnical Investigation Report for the Brine Disposal Pipeline Cities of Beaumont, Redlands, Loma Linda, and San Bernardino Riverside and San Bernardino Counties, California
May 30, 2017

Copyright 2017 Converse Consultants
Converse Project No. 16-81-255-02 ii

PROFESSIONAL CERTIFICATION

This report has been prepared by the individuals whose seals an d signatures appear herein.

The findings, recommendations, specifications, or professional opinions contained in this report were prepared in accordance with generally accepted professional engineering , engineering geologic principles, and practice in this area of Southern California. There is no warranty, either expressed or implied.

Hashmi S. E. Quazi, PhD, PE, GE
Principal Engineer
Scot Mathis, PG, CEG
Senior Geologist

Geotechnical Investigation Report for the Brine Disposal Pipeline Cities of Beaumont, Redlands, Loma Linda, and San Bernardino Riverside and San Bernardino Counties, California
May 30, 2017

Copyright 2017 Converse Consultants
Converse Project No. 16-81-255-02 iii

EXECUTIVE SUMMARY

The following is a summary of our geotechnic al investigation, conclusions, and recommendations, as presented in the body of this report. Please refer to the appropriate sections of the report for complete conclusions and recommendations. In the event of a conflict between this summary and the report , or an omission in the summary, the report shall prevail.

• The proposed pipeline for the Brine Disposal Pipeline project consists of 12-inch- diameter HDPE pipeline, to be installed in three reaches along West 4th Street, Portrero Boulevard, Oak Valley Parkway, San Timoteo Canyon Road, Beaumont Avenue, Nevada Street, Bermudez Street, New Jersey Street, Orange Avenue, California Street, Bryn Mawr Avenue, Redlands Boulevard, and South Hunts Lane, in the cities of Beaumont, Redlands, Loma Linda, and San Bernar dino, in Riverside and San Bernardino Counties, California.

• The majority of the pipeline will be installed using the open cut -and-cover technique with a typical depth to pipe invert of 6 feet below ground surface . Bore- and-jack or horizontal direction drilling (HDD) trenchless construction methods will be utilized at critical crossings.

• Our scope of work included project set-up, subsurface exploration, laboratory testing, engineering analysis, and preparation of this report.

• Thirty exploratory borings were drilled between March 20 and March 23, 2017, at locations along the proposed alignment reaches. The borings were drilled to depths ranging from approximately 1.2 to 16.5 feet below the existing ground surface (bgs). Where encountered, existing pavement thicknesses were measured at the boring locations.

• Based on the exploratory borings, the subsurface materials primarily consisted of unconsolidated to moderately consolidated alluvial sediments consisting of sand, silt, and clay mixtures with scattered gravel. Layers of loose sand were encountered in some isolated borings. Loose sand layers may have the potential for caving during construction.

• Groundwater was not encountered during the investigation to the maximum explored depth of 16.5 feet bgs . The historical high groundwater level varies throughout the alignment but is shallower than the proposed 10 -foot depth of pipe in some localized areas. Based on the absence of groundwater in the borings, the current depth to groundwater is likely deeper than 16.5 feet bgs throughout the majority of the alignment.

• Several small lakes are present adjacent to San Timoteo Canyon Road in the vicinity of borings BH-13 through BH-15. No groundwater was encountered in the

Geotechnical Investigation Report for the Brine Disposal Pipeline Cities of Beaumont, Redlands, Loma Linda, and San Bernardino Riverside and San Bernardino Counties, California
May 30, 2017

Copyright 2017 Converse Consultants
Converse Project No. 16-81-255-02 iv

nearby borings during our investigation, howeve r, some seepage from these lakes may be encountered during construction in areas adjacent to or in close proximity to the lakes. If groundwater is encountered during construction, dewatering may be required.

• The alignment crosses the State of California and San Bernardino County designated San Jacinto Fault Zone along South E Street from approximately 750 feet west of the intersection of South E Street and Hunts Lane to the termination of the alignment. The alignment crosses the Riverside County designated Beaumont Plain Fault Zone in the vicinity of the intersection of Western Knolls Avenue and Potrero Boulevard. There is potential for surface rupture resulting from the movement of the San Jacinto Fault and Beaumont Plain Fault. The potential for surface rupture in other areas of the alignment is not known with certainty, but is considered low.

• The alignment is located in a seismically active region. Ground shaking from earthquakes associated with nearby and distant faults may occur during the lifetime of the project. Seismic coefficients derived from the 2016 California Building Code are presented in the text of this report.

• The potential impact to the project alignment from land sliding lateral spreading, tsunamis, and earth-quake-induced flooding is considered to be low.

• Liquefaction potential varies along the alignment and is discussed in detail within the text of the report.

• The alignment along San Timoteo Canyon Road runs adjacent to a few small lakes.

In this area, there may be risk of flooding due to seiching. Along other areas of the alignment, the risk of flooding due to seiching is considered low.

• The sulfate and chloride contents of the majority of the soils along the proposed alignment correspond to American Concrete Institute (ACI) exposu re category S0 and C1, respectively.

• The measured values of the minimum electrical resistivity when saturated ranged from 1,400 to 4,600 Ohm-cm. This indicates that the majority of the soils along the proposed alignment are corrosive for ferrous metals i n contact with the soil. A corrosion engineer should be consulted for corrosion mitigation measures for ferrous metals in contact with the soil.

• Prior to the start of construction, all existing underground utilities should be located along the pipeline alignment and at the turnout facilities. Such utilities should either be protected in-place, or removed and replaced during construction as required by the project specifications.

Geotechnical Investigation Report for the Brine Disposal Pipeline Cities of Beaumont, Redlands, Loma Linda, and San Bernardino Riverside and San Bernardino Counties, California
May 30, 2017

Copyright 2017 Converse Consultants
Converse Project No. 16-81-255-02 v

• Earthwork for the pipeline includes pipe trench excavation, pipe subgrade preparation, and backfilling of the trench following the placement of the pipe.

Excavated site soils free of particles larger than 3 inches and deleterious matter may be used for backfill. The backfill materials should be brought to within  3 percent of optimum moisture content for coarse grained soil and between optimum and above 2 percent of optimum for fine grained soil, then placed in horizontal layers not exceeding loose lifts of 8 inches. All backfill material should be compacted to a minimum of 90 per cent of the laboratory maximum dry density.

The upper 1 foot of backfill beneath the pavement sections should be compacted to at least 95 percent of the laboratory maximum dry density.

• Additional borings should be completed at identified critical bore -and-jack or HDD crossings.

• Allowable net bearing capacities, lateral earth pressures, and pipeline design parameters are presented in the text of this report. Slope ratios for temporary excavations and shoring recommendations are also provided in the text of this report.

The results of our investigation indicate that the proposed project is feasible from a geotechnical standpoint, provided that the recommendations presented in this report are considered and implemented in the design and construction of the pipeline.

Geotechnical Investigation Report for the Brine Disposal Pipeline Cities of Beaumont, Redlands, Loma Linda, and San Bernardino Riverside and San Bernardino Counties, California
May 30, 2017

Copyright 2017 Converse Consultants
Converse Project No. 16-81-255-02 vi

TABLE OF CONTENTS

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

2.0 PROJECT AND ALIGNMENT DESCRIPTION ...................................................................... 2

3.0 SCOPE OF WORK ............................................................................................................... 3

3.1 PROJECT SET-UP ................................................................................................................ 3

3.2 SUBSURFACE EXPLORATION ................................................................................................ 3

3.3 LABORATORY TESTING ........................................................................................................ 4

3.4 ANALYSIS AND REPORT PREPARATION ................................................................................. 4

4.0 ALIGNMENT CONDITIONS .................................................................................................. 6

4.1 EXISTING PAVEMENT SECTIONS ........................................................................................... 6

4.2 GROUNDWATER .................................................................................................................. 6

4.3 SUBSURFACE PROFILE ........................................................................................................ 8

4.4 EXCAVATABILITY ................................................................................................................. 8

4.5 SUBSURFACE VARIATIONS ................................................................................................... 8

5.0 LABORATORY TEST RESULTS .......................................................................................... 9

5.1 PHYSICAL TESTING .............................................................................................................. 9

5.2 CHEMICAL TESTING - CORROSIVITY EVALUATION ................................................................ 10

6.0 GEOLOGIC SETTING ........................................................................................................ 11

6.1 REGIONAL GEOLOGY ......................................................................................................... 11

6.2 LOCAL GEOLOGY .............................................................................................................. 11

7.0 FAULTING AND SEISMICITY ............................................................................................. 13

7.1 FAULTING ......................................................................................................................... 13

7.2 SEISMIC DESIGN PARAMETERS .......................................................................................... 13

7.3 SECONDARY EFFECTS OF SEISMIC ACTIVITY ....................................................................... 14

8.0 EARTHWORK RECOMMENDATIONS ............................................................................... 17

8.1 GENERAL .......................................................................................................................... 17

8.2 PIPELINE SUBGRADE PREPARATION ................................................................................... 17

8.3 PIPE BEDDING ................................................................................................................... 17

8.4 TRENCH ZONE BACKFILL ................................................................................................... 18

9.0 DESIGN RECOMMENDATIONS ....................................................................................... 20

9.1 GENERAL .......................................................................................................................... 20

9.2 RESISTANCE TO LATERAL LOADS ....................................................................................... 20

9.3 SOIL PARAMETERS FOR PIPE DESIGN ................................................................................. 20

9.4 BEARING PRESSURE FOR ANCHOR AND THRUST BLOCKS .................................................... 21

9.5 PIPELINE FAULT CROSSINGS .............................................................................................. 21

9.6 SOIL CORROSIVITY ............................................................................................................ 22

10.0 CONSTRUCTION RECOMMENDATIONS ...................................................................... 23

10.1 GENERAL ...................................................................................................................... 23

Geotechnical Investigation Report for the Brine Disposal Pipeline Cities of Beaumont, Redlands, Loma Linda, and San Bernardino Riverside and San Bernardino Counties, California
May 30, 2017

Copyright 2017 Converse Consultants
Converse Project No. 16-81-255-02 vii

10.2 TEMPORARY SLOPED EXCAVATIONS ............................................................................... 23

10.3 SHORING DESIGN .......................................................................................................... 24

11.0 GEOTECHNICAL SERVICES DURING CONSTRUCTION ............................................. 27

12.0 CLOSURE ....................................................................................................................... 28

13.0 REFERENCES ................................................................................................................ 29

TABLES
Page Number
Table No. 1, Pipeline Alignment .................................................................................................... 2 Table No. 2, Boring Details ........................................................................................................... 3 Table No. 3, Existing Pavement Sections ..................................................................................... 6 Table No. 4, Corrosivity Test Results .......................................................................................... 10 Table No. 5, Local Geologic Units ............................................................................................... 12 Table No. 6, CBC 2016 Seismic Parameters .............................................................................. 13 Table No. 7, Liquefaction Potential ............................................................................................. 15 Table No. 8, Resistance to Lateral Loads ................................................................................... 20 Table No. 9, Soil Parameters for Pipe Design ............................................................................. 21 Table No. 10, Slope Ratios for Temporary Excavations .............................................................. 23 Table No. 11, Lateral Earth Pressures for Temporary Shoring ................................................... 24

FIGURES
Following Page Number
Figure No. 1, Approximate Alignment Location Map ..................................................................... 1 Figure No. 2, Approximate Boring Locations Map ......................................................................... 4 Figure No. 3, Approximate Alignment over Geologic Map ........................................................... 11 Figure No. 4, San Jacinto Fault Zone Crossing ........................................................................... 13 Figure No. 5, Beaumont Plain Fault Zone Crossing .................................................................... 13 Figure No. 6, Southern California Regional Fault Map ................................................................ 13 Figure No. 7, Lateral Earth Pressures for Temporary Braced Excavation ................................... 24 Figure No. 8, Lateral Earth Pressures on Temporary Cantilever Wall ......................................... 24

APPENDICES

Appendix A ........................................................................................................... Field Exploration Appendix B ......................................................................................... Laboratory Testing Program

Geotechnical Investigation Report for the Brine Disposal Pipeline Cities of Beaumont, Redlands, Loma Linda, and San Bernardino Riverside and San Bernardino Counties, California
May 30, 2017

Copyright 2017 Converse Consultants
Converse Project No. 16-81-255-02 1

1.0 INTRODUCTION

This report contains the findings of the geotechnical investigation performed by Converse for the City of Beaumont Public Works Department Brine Disposal Pipeline to be installed in the cities of Beaumont, Redlands, Loma Linda, San Bernardino and Riverside and San Bernardino Counties, California. The approximate location of the proposed pipeline alignment is shown in Figure No. 1, Approximate Alignment Location Map.

The purpose of this investigation was to evaluate the nature and engineering properties of the subsurface soils and groundwater conditions, and to provide geotechnical recommendations for the design and construction of the proposed pipeline.

This report was prepared for the project described herein and is intended for use solely by Albert A. Webb Associates and its authorized agents. This report may be made available to the prospective bidders for bidding purposes. However, the bidders are responsible for their own interpretation of the site conditions between and beyond the boring locations, based on factual data contained in this report. This report may not contain sufficient information for use by others and/or other purposes.

Converse Consultants
Project No.

Figure No.
16 -81 -255-02
Approximate Alignment Location Map
Project:

Location:

For:

Brine Disposal Pipeline
Cities of Beaumont, Redlands, Loma Linda, and San Bernardino Riverside and San Bernardino Counties, California
Albert A. Webb Associates
1 Point of
Connection
Reach A
Reach B

Geotechnical Investigation Report for the Brine Disposal Pipeline Cities of Beaumont, Redlands, Loma Linda, and San Bernardino Riverside and San Bernardino Counties, California
May 30, 2017

Copyright 2017 Converse Consultants
Converse Project No. 16-81-255-02 2

2.0 PROJECT AND ALIGNMENT DESCRIPTION

The proposed alignment is divided into three reaches and traverses several roads as described in the following table.

Table No. 1, Pipeline Alignment
Reach Road Limits

West 4th Street WWTP west to end of street.

N/A End of West 4th Street north to Portrero Boulevard
Potrero Boulevard End of Western Knolls Avenue to Oak Valley Parkway Oak Valley Parkway Potrero Boulevard to San Timoteo Canyon Road San Timoteo Canyon Road Oak Valley Parkway to Live Oak Canyon Road 2 San Timoteo Canyon Road Live Oak Canyon Road to Railroad Crossing 3 San Timoteo Canyon Road Railroad Crossing to Beaumont Avenue Beaumont Avenue San Timoteo Canyon Road to Nevada Street Nevada Street Beaumont Avenue to San Timoteo Canyon Road San Timoteo Canyon Road Nevada Street to Bermudez Street Bermudez Street San Timoteo Canyon Road to New Jersey Street New Jersey Street Bermudez Street to Orange Avenue
Orange Avenue New Jersey Street to California Street
California Street Orange Avenue to Park Avenue
N/A West from Park Avenue to Bryn Mawr Avenue
Bryn Mawr Avenue South end of Bryn Mawr Avenue to Redlands Boulevard Redlands Boulevard Bryn Mawr Avenue to South Hunts Lane South Hunts Lane Redlands Boulevard to South E Street
South E Street South Hunts Lane to Santa Ana River Crossing N/A Santa Ana River Crossing

W e understand that the pipe will be 12-inch-diameter HDPE (13.2-inch outer diameter) and that the typical depth to pipe invert will be approximately 6 feet below existing ground surface (bgs). The pipeline will be installed using the open cut-and-cover, and bore-and- jack or horizontal direction drilling (HDD) techniques.

We understand that 12 critical crossing locations have been identified for potential bore- and-jack or HDD pipeline installation but are not part of the scope of work for this investigation.

Roadway conditions throughout the project alignment including lane numbers and widths, shoulder conditions, and traffic conditions vary widely.

At the time this report was being prepared, sections of California Street and San Timoteo Canyon Road were being repaved along portions of the alignment.

Geotechnical Investigation Report for the Brine Disposal Pipeline Cities of Beaumont, Redlands, Loma Linda, and San Bernardino Riverside and San Bernardino Counties, California
May 30, 2017

Copyright 2017 Converse Consultants
Converse Project No. 16-81-255-02 3

3.0 SCOPE OF WORK

The scope of Converse’s investigation is described in the following sections.

3.1 Project Set-up

The project set-up consisted of the following tasks.

• Conducted a site reconnaissance to mark the borings at representative locations throughout the alignment.
• Obtained encroachment permits from the Cities of Beaumont, Redlands, Loma Linda, San Bernardino, and Riverside County.
• Notified Underground Service Alert (USA) at least 48 hours prior to drilling to clear the boring locations of any conflict with existing underground utilities. • Engaged a drilling subcontractor.

3.2 Subsurface Exploration

Thirty-eight possible boring locations were identified and marked in the field. Thirty exploratory borings were drilled to investigate the subsurface conditions. The boring details including date drilled, approximate coordinates, boring depth, and notes are described in the following table.

Table No. 2, Boring Details
Boring
No. Date Drilled Approximate
Coordinates
Boring Depth
(ft. bgs) Notes
BH-1 3/21/2017 33.9253, -116.9954 16.5 Drilled as planned BH-2 3/21/2017 33.9264, -116.9994 16.5 Drilled as planned BH-4 3/21/2017 33.9339, -117.0082 16.5 Drilled as planned BH-5 3/21/2017 33.9366, -117.0168 16.5 Drilled as planned BH-7 3/21/2017 33.9435, -117.0325 16.5 Drilled as planned BH-8 3/21/2017 33.9443, -117.0464 16.5 Drilled as planned BH-9 3/21/2017 33.9513, -117.0565 5.0 Artificial gravel layer encountered BH-10 3/21/2017 33.9589, -117.0651 16.5 Drilled as planned BH-12 3/22/2017 33.9722, -117.0826 16.5 Drilled as planned BH-13 3/22/2017 33.9741, -117.0928 16.5 Drilled as planned BH-14 3/22/2017 33.9768, -117.1036 16.5 Drilled as planned BH-15 3/22/2017 33.9799, -117.1129 16.5 Drilled as planned BH-16 3/22/2017 33.9803, -117.1225 16.5 Drilled as planned BH-18 3/22/2017 33.9861, -117.1436 16.5 Drilled as planned BH-21 3/23/2017 34.0028, -117.1667 16.5 Drilled as planned BH-22 3/23/2017 34.0085, -117.1745 16.5 Drilled as planned BH-23 3/23/2017 34.0132, -117.1836 16.5 Drilled as planned

Geotechnical Investigation Report for the Brine Disposal Pipeline Cities of Beaumont, Redlands, Loma Linda, and San Bernardino Riverside and San Bernardino Counties, California
May 30, 2017

Copyright 2017 Converse Consultants
Converse Project No. 16-81-255-02 4

Boring
No. Date Drilled Approximate
Coordinates
Boring Depth
(ft. bgs) Notes
BH-24 3/23/2017 34.0202, -117.1919 5.0 Refusal encountered BH-26 3/23/2017 34.0315, -117.2083 16.5 Drilled as planned BH-27 3/23/2017 34.0398, -117.2117 16.5 Drilled as planned BH-28 3/23/2017 34.0459, -117.2175 16.5 Drilled as planned BH-29 3/20/2017 34.0521, -117.2217 16.5 Drilled as planned BH-30 3/20/2017 34.0573, -117.2263 16.5 Drilled as planned BH-31 3/20/2017 34.0630, -117.2309 16.5 Drilled as planned BH-32 3/20/2017 34.0631, -117.2426 16.5 Drilled as planned BH-33 3/20/2017 34.0631, -117.2536 1.2 Refusal on concrete at 14 inches BH-34 3/20/2017 34.0631, -117.2634 16.5 Drilled as planned BH-35 3/20/2017 34.0630, -117.2735 16.5 Drilled as planned BH-36 3/20/2017 34.0629, -117.2832 16.5 Drilled as planned BH-38 3/20/2017 34.0666, -117.2939 16.5 Drilled as planned

The approximate locations of the borings are shown on Figure No. 2, Approximate Boring Locations Maps. A detailed discussion of the subsurface exploration is presented in Appendix A, Field Exploration.

3.3 Laboratory Testing

Representative samples of soils along the alignments were tested in the laboratory to aid in soil classification, and to evaluate relevant engineering properties. These tests included the following.

• In situ moisture contents and dry densities (ASTM D2216) • Expansion Index (ASTM D4318)
• Sand Equivalent (ASTM D2419)
• Soil corrosivity (California Test Methods 643, 422, and 417) • Swell/Collapse tests (ASTM D4546)
• Grain size analysis (ASTM D422)
• Maximum dry density and optimum-moisture content (ASTM D1557) • Direct shear (ASTM D3080)

For in-situ moisture and dry density data, see the logs of borings in Appendix A, Field Exploration. For a description of the laboratory test methods and test results, see Appendix B, Laboratory Testing Program.

3.4 Analysis and Report Preparation

Data obtained from the field exploration and l aboratory testing program was assembled and evaluated. Geotechnical analyses of the compiled data were performed, followed by

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Project No.

Figure No.
16-81-255-02

Approximate Boring Location Map
Project:Brine Disposal Pipeline
Location:Cities of Beaumont, Redlands, Loma Linda, and San Bernardino Riverside and San Bernardino Counties, California
For:Albert A. Webb Associates
2a
BH-1
BH-2
BH-3BH-4
BH-5
BH-6
BH-7BH-8
BH-9
BH-10 EXPLANATION
BH-10
BH-6
Number and Approximate Location
of Completed Soil Boring
Number and Approximate Location
of Undrilled Soil Boring
(ND)
(ND)
(ND)
0 0.25 0.5
mi
0 0.25 0.5
mi

Converse Consultants
Project No.

Figure No.
16-81-255-02

Approximate Boring Location Map
Project:Brine Disposal Pipeline
Location:Cities of Beaumont, Redlands, Loma Linda, and San Bernardino Riverside and San Bernardino Counties, California
For:Albert A. Webb Associates
2b
BH-11
BH-12
BH-13
BH-14
BH-15
BH-16
BH-17
(ND)
(ND)

EXPLANATION
BH-16
BH-17
Number and Approximate Location
of Completed Soil Boring
Number and Approximate Location
of Undrilled Soil Boring
(ND)
0 0.25 0.5
mi
0 0.25 0.5
mi

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Project No.

Figure No.
16-81-255-02

Approximate Boring Location Map
Project:Brine Disposal Pipeline
Location:Cities of Beaumont, Redlands, Loma Linda, and San Bernardino Riverside and San Bernardino Counties, California
For:Albert A. Webb Associates
2c
BH-18
BH-19
BH-20
BH-21
BH-22
BH-23
(ND)
(ND)

EXPLANATION
BH-23
BH-20
Number and Approximate Location
of Completed Soil Boring
Number and Approximate Location
of Undrilled Soil Boring
(ND)
0 0.25 0.5
mi
0 0.25 0.5
mi

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Project No.

Figure No.
16-81-255-02

Approximate Boring Location Map
Project:Brine Disposal Pipeline
Location:Cities of Beaumont, Redlands, Loma Linda, and San Bernardino Riverside and San Bernardino Counties, California
For:Albert A. Webb Associates
2d
BH-24
BH-25
BH-26
BH-27b
BH-28
BH-29
(ND)

EXPLANATION
BH-29
BH-25
Number and Approximate Location
of Completed Soil Boring
Number and Approximate Location
of Undrilled Soil Boring
(ND)
0 0.25 0.5
mi
0 0.25 0.5
mi

Converse Consultants
Project No.

Figure No.
16-81-255-02

Approximate Boring Location Map
Project:Brine Disposal Pipeline
Location:Cities of Beaumont, Redlands, Loma Linda, and San Bernardino Riverside and San Bernardino Counties, California
For:Albert A. Webb Associates
2e
BH-30
BH-31BH-32BH-33BH-34BH-35BH-36
BH-37
BH-38
(ND)

EXPLANATION
BH-38
BH-37
Number and Approximate Location
of Completed Soil Boring
Number and Approximate Location
of Undrilled Soil Boring
(ND)
0 0.25 0.5
mi
0 0.25 0.5
mi

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Converse Project No. 16-81-255-02 5

the preparation of this report to present our findings, conclusions, and recommendations for the proposed pipeline alignment.

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4.0 ALIGNMENT CONDITIONS

The subsurface conditions are discussed in the subsections below.

4.1 Existing Pavement Sections

The pavement thicknesses were measured where encountered and are included in the following table.

Table No. 3, Existing Pavement Sections
Boring No. Street Asphalt Concrete Thickness
(in.)
Aggregate Base Thickness
(in.)
BH-1 Risco Circle 3.0 7.0
BH-2 West 4th Street 6.0 12.0
BH-7 Oak Valley Parkway 6.0 6.0
BH-8 Oak Valley Parkway 6.0 6.0
BH-10 Oak Valley Parkway 6.0 6.0
BH-30 California Street 3.5 3.5
BH-31 Redlands Boulevard 9.0 5.0
BH-32 Redlands Boulevard 9.0 8.0
BH-33 Redlands Boulevard 6.0 7.0
BH-35 Redlands Boulevard 6.0 7.0
BH-36 Redlands Boulevard 5.0 8.0
BH-38 South E Street 6.5 6.0

For a detailed description of the subsurface materials encountered in the exploratory borings, see Drawings No. A-2 through A-31, Logs of Borings, in Appendix A, Field Exploration.

4.2 Groundwater

Groundwater was not encountered during the investigation to the maximum explored depth of 16.5 feet bgs.

Regional groundwater data (SWRCB, 2017) from locations within close proximity to the alignment was reviewed to evaluate the current and historical groundwater levels.

Findings are summarized below.

• Haskell Ranch (ID No. T0606500408) located approximately 750 feet southeast of the intersection of Oak Valley Parkway and Palmer Avenue near boring BH-10 reported groundwater depths between 2.9 and 4 feet bgs in 1995.

• Union Pacific Railroad San Timoteo Canyon Derailment (ID No. T10000000882), located approximately 800 feet southeast of the intersection of Live Oak Canyon

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Road and San Timoteo Canyon Road, and approximately 1,200 feet southeast of boring BH-21 reported groundwater depths between 5 and 33 feet begs in 2008 and 2009. This location is adjacent to an active creek channel and approximately 180 feet from the proposed alignment.

• William Brown Facility (T0607100484) located approximately 3,000 feet east of the intersection of San Timoteo Canyon Road and Beaumont Avenue reported groundwater depths between 195 and 1999 feet bgs in 2005.

• ARCO #5205 (T0607100322) located at the intersection of Redlands Boulevard and California Street adjacent to the alignment reported groundwater depths between 80 and 100 feet bs in 1993.

• CIRCLE K #0498 (T0607100323) located at the intersection of Redlands Boulevard and Coloma Street adjacent to the alignment reported groundwater at a depth of 100 feet bgs in 1996.

• UNOCAL #2417 (T0607100008) located at the intersection of Redlands Boulevard and Anderson Street adjacent to the alignment reported groundwater at depths between 34 and 44 feet bgs between 1989 and 2010.

• ARCO #5214 (T0607100180) located at the intersection of Redlands Boulevard and South Waterman Avenue adjacent to the alignment reported ground water at depths between 10 and 61 feet bgs between 1997 and 2010.

• TRUCK O MAT (T0607100235) located at the intersection of South E Street and South Hunts Lane adjacent to the alignment reported groundwater at depths between 34 and 40 bgs in 2016.

Several small lakes are present adjacent to San Timoteo Canyon Road in the vicinity of borings BH-13 through BH-15. No groundwater was encountered in the nearby borings during our investigation, however, some seepage from these lakes may be encountered during construction in areas adjacent to or in close proximity to the lakes. If groundwater is encountered during construction, dewatering may be required.

Based on the data reviewed, the historical high groundwater level in localized areas along the alignment is shallower than the proposed 10-foot depth of pipe. Based on the absence of groundwater in the exploratory borings, current groundwater is generally expected to be deeper than 16 feet bgs throughout the alignment .

It should be noted that the groundwater level could vary depending upon seasonal precipitation and any active groundwater pumping activity in the region. Shallow perched groundwater may be present locally, particularly following precipitation or irrigation events.

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4.3 Subsurface Profile

Based on the exploratory borings, the subsurface materials primarily consisted of unconsolidated to moderately consolidated alluvial sediments consisting of sand, silt, and clay mixtures with scattered gravel. Layers of loose sand were encountered in some isolated borings. Loose sand layers may have the potential for caving during construction.

For a detailed description of the subsurface materials encountered in the exploratory borings, see Drawings No. A-2 through A-31, Logs of Borings, in Appendix A, Field Exploration.

4.4 Excavatability

The subsurface materials along the alignment are expected to be excavatable by conventional heavy-duty earth moving equipment.

The phrase “conventional heavy-duty excavation equipment” is intended to include commonly used equipment such as excavators, scrapers, and trenching machines. It does not include hydraulic hammers (“breakers”), jackhammers, blasting, or other specialized equipment and techniques used to excavate hard earth materials. Selection of an appropriate excavation equipment models should be done by an experienced earthwork contractor.

4.5 Subsurface Variations

Based on results of the subsurface exploration and our experience, some variations in the continuity and nature of subsurface conditions along the alignment should be anticipated. Because of the uncertainties involved in the nature and depositional characteristics of the earth material, care should be exercised in interpolating or extrapolating subsurface conditions between or beyond the boring locatio ns.

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5.0 LABORATORY TEST RESULTS

Laboratory testing was performed to determine the physical and chemical characteristics and engineering properties of the subsurface soils. Tests results are included in Appendix A, Field Exploration and Appendix B, Laboratory Testing Program. Discussions of the various test results are presented below:

5.1 Physical Testing

• In-situ Moisture and Dry Density – In-situ dry density and moisture content of the site soils were determined in accordance to ASTM Standard D2216. Dry densities of soils along the alignment ranged from 93 to 128 pcf with moisture contents ranging from 1 to 29 percent. Results are presented in the log of borings in Appendix A, Field Exploration.

• Expansion Index – Five representative bulk soil samples were tested to evaluate expansion potential of soils in accordance with the ASTM Standard D4829 test method. The measured expansion index of the soil samples tested ranged from 0 to 8.

• Sand Equivalent – Seven representative bulk soil samples were tested to evaluate sand equivalent (SE) in accordance with the ASTM Standard D2419 test method.

The measured sand equivalents ranged from 7 to 38.

• Collapse Potential – The collapse potential of two relatively undisturbed samples were tested under a vertical stress of up to 2.0 kips per square foot (ksf) in accordance with the ASTM Standard D4546 test method. The results are pending.

• Grain Size Analysis – Eight representative samples were tested to determine their relative grain size distributions in accordance with the ASTM Standard D422. Test results are graphically presented in Drawing No. B-1, Grain Size Distribution Results.

• Maximum Dry Density and Optimum Moisture Content – Seven moisture-density relationships of representative soil samples were tested in accordance to ASTM Standard D1557. The results are presented in Drawing No. B-2, Moisture-Density Relationship Results, in Appendix B, Laboratory Testing Program. The laboratory maximum dry densities ranged from 118.0 to 132.1 pounds per cubic feet (pcf), with an optimum moisture contents ranging from 7.0 to 11.0 percent.

• Direct Shear – Seven direct shear tests were performed on relatively undisturbed representative soil samples at soaked moisture conditions per ASTM D3080.

Results of the direct shear tests are presented in Drawings No. B-3 and B-9, Direct Shear Test Results in Appendix B, Laboratory Testing Program.

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5.2 Chemical Testing - Corrosivity Evaluation

Seven representative soil samples were tested to determine minimum electrical resistivity, pH, and chemical content, including soluble sulfate and chloride concentrations. The purpose of these tests was to determine the corrosion potential of site soils when placed in contact with common pipe materials. These tests were performed by EG Labs in accordance with California Test Methods 643, 422, and 417.

The test results are summarized in the table below and are presented in Appendix B, Laboratory Testing Program. These results are discussed in Section 10.6, Soil Corrosivity.

Table No. 4, Corrosivity Test Results
Boring
No.

Depth
(feet) pH
Soluble Sulfates
(CA 417)
(percent by weight)
Soluble Chlorides
(CA 422)
(ppm)
Min. Resistivity
(CA 643)
(Ohm-cm)
BH-1 1.0-5.0 7.94 0.018 360 3,300
BH-5 1.0-5.0 7.11 0.036 290 3,200
BH-12 1.0-5.0 7.84 0.002 380 1,400
BH-18 1.0-5.0 8.05 0.003 130 2,500
BH-26 1.0-5.0 7.98 0.004 140 3,200
BH-32 1.0-5.0 8.08 0.003 145 4,600
BH-38 1.0-5.0 7.79 0.009 125 2,300

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6.0 GEOLOGIC SETTING

The regional and local geology are discussed in the following subsections.

6.1 Regional Geology

The proposed alignment is located within the Northern Peninsular Ranges Geomorphic Province of Southern California. The Peninsular Ranges Geomorphic Province consists of a series of northwest-trending mountain ranges and valleys bounded on the north by the San Bernardino and San Gabriel Mountains, on the west by the Los Angeles Basin, and on the southwest by the Pacific Ocean.

The province is a seismically active region characterized by a series of northwest - trending strike-slip faults. The most prominent of the nearby fault zones include the San Jacinto, San Andreas, and Cucamonga Fault Zones, all of which have been known to be active during Quaternary time.

Topography within the province is generally characterized by broad alluvial valleys separated by linear mountain ranges. This northwest -trending linear fabric is created by the regional faulting within the granitic basement rock of the Southern California Batholith. Broad, linear, alluvial valleys have been formed by erosion of th ese principally granitic mountain ranges.

6.2 Local Geology

The geology along the alignment is complex and is comprised of several different units.

The geology along the alignment is shown on Figure No. 3, Approximate Alignment over Geologic Map.

The alignment runs through San Timoteo Canyon, a river-cut valley in the western reaches of the foothills of the San Jacinto Mountains. Erosion and deposition is still active, especially during periods of heavy rainfall. The active San Timoteo Creek begins west of Beaumont, flows through the entire length of the canyon, and drains into the Santa Ana River.

The alignment commences in an old alluvial valley at the base of the western reaches of the San Jacinto Mountain foothills. The alignment traverses west -northwest through San Timoteo Canyon and emerges into a complex, faulted alluvial valley consisting of units deposited by the active Santa Ana River and by streams emerging from the western - most extent of the San Jacinto Mountain foothills to the south. There are several mapped fault traces associated with the San Jacinto Fault System in the area, some of which cross the proposed alignment. Faulting is discussed further in Section 8.0, Faulting and Seismicity. Based on review available geologic mapping (Morton and Miller, 2006), the following geologic units will likely be encountered along the alignment.

EXPLANATION
Qwag – Very young wash deposits
Qf – Very young alluvial -fan deposits
Qa –Very young axial channel
deposits
Qyf3 – Young alluvial-fan deposits
Qya5 – Young axial channel deposits
Qyls – Young landslide deposits
Qof –Old alluvial-fan deposits
Qoa – Old axial channel deposits
Qvoa3 – Very old axial channel deposits
Qvof – Very old alluvial-fan deposits
Qstu – San Pedro Sandstone, upper
member (Pleistocene),
moderately indurated, very fine -
to coarse-grained
Tstm – San Pedro Sandstone, middle
member (Pliocene), well
indurated, coarse -grained
1 mile
Base map credits:

MORTON, D.M. and MILLER, F.K., 2006, Geologic Map of the San Bernardino and Santa Ana 30' x 60' Quadrangles, California, U.S. Geological Survey Open- File Report 2006-1217, scale 1:100,000
Dibblee, T.W., and Minch, J.A., 2003, Geologic map of the Beaumont quadrangle, Riverside County, California: Dibblee Geological Foundation, Dibblee Foundation Map DF-114, scale 1:24,000
Converse Consultants Drawing No.
3 Project No.
16 -81 -255-02
Project:

Location:

For:

Brine Disposal Pipeline
Cities of Beaumont, Redlands, Loma Linda, and San Bernardino Counties of Riverside and San Bernardino, California
Albert A. Webb Associates
Approximate Alignment over Geologic Map
Point of
Connection
Reach A
Reach B

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Converse Project No. 16-81-255-02 12

Table No. 5, Local Geologic Units
Geologic
Unit Name Description
Qoa Old alluvium
deposits
Late Pleistocene-aged alluvial fan sand and gravel, may be weakly indurated
Qvof Very old alluvial fan
deposits
Middle to early Pleistocene-aged moderately to well-consolidated silt, sand, gravel and conglomerate
Qya Young axial
channel deposits
Holocene and late Pleistocene-aged slightly to moderately consolidated silt, sand, and gravel deposits
Qyls Young landslide
deposits
Holocene and late Pleistocene-aged slope failure deposits consisting of displaced bedrock blocks or mixed rubble
Qf Very young alluvial
fan deposits
Late Holocene-aged unconsolidated deposits of sand, gravel, and boulders
Qyf Young alluvial fan
deposits
Holocene and late Pleistocene-aged unconsolidated to moderately consolidated silt, sand, cobbles, and boulders
Qa Very young axial
channel deposits
Late Holocene-aged unconsolidated deposits of silt, sand, and cobbles
Qw Very young wash
deposits
Late Holocene-aged unconsolidated sand and gravel deposits in active streams

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Converse Project No. 16-81-255-02 13

7.0 FAULTING AND SEISMICITY

Nearby active faults, seismicity, and their impact on the project are discussed in the following sections.

7.1 Faulting

The alignment crosses the State of California and San Bernardino County designated San Jacinto Fault Zone along South E Street from approximately 750 feet west of the intersection of South E Street and Hunts Lane to the termination of the alignment (CGS, 1977a, San Bernardino County 2010a, 2010b, 2010c, 2010d). There are no other State of California Designated Earthquake Fault Zones projecting toward or extending across the alignment (CGS, 1974, 1977b, 1995a, 1995b). The fault zone crossing is shown on Figure No. 4. San Jacinto Fault Zone Crossing following this page.

The alignment crosses the Riverside County designated Beaumont Plain Fault Zone in the vicinity of the intersection of Western Knolls Avenue and Potrero Boulevard (Riverside County, 2017). There are no other Riverside County Designated Fault Zones project toward or extending across the alignment. The fault zone crossing is shown on Figure No. 5. Beaumont Plain Fault Zone Crossing following this page.

There is potential for surface rupture resulting from the movement of the San Jacinto Fault and Beaumont Plain Fault. The potential for surface rupture in other areas of the alignment is not known with certainty, but is considered low.

The alignment is situated in a seismically active region. As is the case for most areas of Southern California, ground shaking resulting from earthquakes associated with nearby and more distant faults may occur at the project site. During the life of the project, seismic activity associated with active faults can be expected to generate moderate to strong ground shaking at the site. A regional map of active faults located within approximately 100 kilometers of the alignment is shown in Figure No. 6, Southern California Regional Fault Map on the following page.

7.2 Seismic Design Parameters

Seismic parameters based on the California Building Code (CBSC, 2016) provided in the table on the following page were determined using the Seismic Design Maps application (USGS, 2017b) and are based on several locations throughout the alignment.

Table No. 6, CBC 2016 Seismic Parameters
Parameter Values
Coordinates 33.9339°N,
117.0081°W

33.9672°N,
117.0746°W

33.9873°N,
117.1455°W

34.0317°N,
117.2084°W

34.0647°N,
117.2916°W
Site Class D D D D D

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Project No
FIGURE
16-81 -255-02
San Jacinto Fault Zone Crossing
Project:

Location:

For:

Brine Disposal Pipeline
Cities of Beaumont, Redlands, Loma Linda, and San Bernardino Riverside and San Bernardino Counties, California
Albert A. Webb Associates
Map adapted from: CALIFORNIA GEOLOGICAL SURVEY (formerly California Division of Mines and Geology), 1977b, Special Studies Zones, San Bernardino South Quadrangle, California, scale 1:24,000, dated January 1, 1977. 4 EXPLANATION
Approximate Pipeline Alignment

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Project No
FIGURE
16-81-255-02

Beaumont Plain Fault Zone Crossing
Project:Brine Disposal Pipeline
Location:Cities of Beaumont, Redlands, Loma Linda, and San Bernardino Riverside and San Bernardino Counties, California
For:Albert A. Webb Associates
Map Adapted From: RIVERSIDE COUNTY, 2016, Riverside County GIS - Map My County ( http://mmc.rivcoit.org/mmc_public) , accessed on April, 2017. 5 EXPLANATION
Riverside County Fault Zone
(Beaumont Plain)
Riverside County Designated Fault
(Beaumont Plain)

0.25 mi
Approximate Pipeline Alignment

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Project No.

Figure No.
16 -81 -255-02
Southern California Regional Fault Map
Project:

Location:

For:

Brine Disposal Pipeline
Cities of Beaumont, Redlands, Loma Linda, and San Bernardino Riverside and San Bernardino Counties, California
Albert A. Webb Associates
Approximate
Alignment Area
Map adapted from: CGS 2002 California Fault Model Modified for Use with FRISKP and EQFAULT by Thomas F. Blake, dated August 2004. 6Page 1201 of 1492

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Parameter Values
Mapped Short period (0.2-sec)
Spectral Response Acceleration, Ss 1.553g 1.734g 2.107g 2.150g 2.553g Mapped 1-second Spectral
Response Acceleration, S1 0.671g 0.759g 0.951g 0.974g 1.170g Site Coefficient (from Table
1613.5.3(1)), Fa 1.0 1.0 1.0 1.0 1.0
Site Coefficient (from Table
1613.5.3(2)), Fv 1.5 1.5 1.5 1.5 1.5
MCE 0.2-sec period Spectral
Response Acceleration, SMs 1.553g 1.734g 2.107g 2.150g 2.553g MCE 1-second period Spectral
Response Acceleration, SM1 1.006g 1.138g 1.426g 1.460g 1.755g Design Spectral Response
Acceleration for short period Sds 1.036g 1.156g 1.404g 1.433g 1.702g Design Spectral Response
Acceleration for 1-second period,
Sd1

0.671g 0.759g 0.951g 0.974g 1.170g
Maximum Peak Ground
Acceleration, PGAM 0.613g 0.679g 0.815g 0.831g 0.982g

7.3 Secondary Effects of Seismic Activity

Generally, in addition to ground shaking, effects of seismic activity on a project site may include surface fault rupture, soil liquefaction, and settlement due to earthquake shaking, landslides, lateral spreading, tsunamis, seiches, and flooding due to earthquake-induced dam failure. The site-specific potential for each of these seismic hazards is discussed in the following sections.

Surface Fault Rupture: The alignment crosses the State of California and San Bernardino County designated San Jacinto and Riverside County designated Beaumont Plain fault zones as discussed in Section 8.1 Faulting, above. The remainder of the alignment is not located within a currently designated State of California or Riverside County Earthquake Fault Zone. There is a potential for surface rupture within the designated fault zones. Outside of the designated fault zones, the potential for surface rupture resulting from the movement of faults is not known with certainty, but is considered low.

Liquefaction: Liquefaction is defined as the phenomenon in which a cohesionless soil mass suffers a substantial reduction in its shear strength due to the development of excess pore pressures. During earthquakes, excess pore pressures in satur ated soil deposits may develop as a result of induced cyclic shear stresses, resulting in liquefaction.

Soil liquefaction generally occurs in submerged granular soils and non -plastic silts located within 50 feet of the ground surface during or after strong ground shaking. There are several general requirements for liquefactio n to occur. They are as follows.

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• Soils must be submerged.
• Soils must be loose to medium-dense.
• Soils must be relatively near the ground surface.
• Ground motion must be intense.
• Duration of shaking must be sufficient for the soils to lose shear resistance .

A quantitative liquefaction analysis is beyond the scope of this report. Liquefaction potential along the alignment based on review of published maps is discussed below.

Reach 1 and 2 alignments are primarily located within areas designated as having moderate susceptibility to liquefaction (Riverside County, 2017).

The Reach 3 alignment is located partially within areas designated by San Bernardino County as not being susceptible to liquefaction and partially within areas designated as having low, medium, or high susceptibility to liquefaction as described in the following table.

Table No. 7, Liquefaction Potential
Street Limits
Liquefaction
Susceptibility (SB
County)
San Timoteo Canyon Road Live Oak Canyon Road to Barton Road Not Designated Barton Road San Timoteo Canyon Road to New Jersey Street Not Designated New Jersey Street Barton Road to Orange Avenue Not Designated Orange Avenue New Jersey Street to California Street Not Designated California Street Orange Avenue to Redlands Boulevard Not Designated Redlands Boulevard California Street to Curtis Street Not Designated Redlands Boulevard Curtis Street to Ohio Street Low
Redlands Boulevard Ohio Street to Gardena Street Medium Redlands Boulevard Gardena Street to South Hunts Lane High South Hunts Lane Redlands Boulevard to South E Street High South E Street South Hunts Lane to Santa Ana River Crossing High N/A Santa Ana River Crossing High

Seismic Settlement: Dry seismic settlement occurs when relatively loose unsaturated sediments above the groundwater elevation may densify and settle when subjected to ground shaking during earthquakes. Young or very young alluvium deposits are more susceptible to dry seismic settlement due to their unconsolidated nature. Older or very older alluvium with have a relatively low potential due to the more dense and consolidated material. Sand layers encountered in several of the borings may be susceptible to dry seismic settlement during an earthquake. A quantitative settlement analysis was beyond the scope of this report.

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Landslides: Seismically induced landslides and other slope failures are common occurrences during or soon after earthquakes. Some sections of the alignment through San Timoteo Canyon are adjacent to steep slopes that may be subject to landsliding.

Lateral Spreading: Seismically induced lateral spreading involves primarily lateral movement of earth materials over deeper layers which have liquefied due to ground shaking. It differs from the slope failure in that complete ground failure involving large movement does not occur due to the relatively smaller gradient of the initial ground surface. Lateral spreading is demonstrated by near-vertical cracks with predominantly horizontal movement of the soil mass involved. In areas where there is a low susceptibility to liquefaction or in old or very old alluvium deposits, the risk of lateral spreading is considered low. In areas where there is a moderate susceptibility to liquefaction and in young or very young alluvium deposits, there may be risk of lateral spreading in areas in proximity to slopes.

Tsunamis: Tsunamis are large waves generated in large bodies of water by fault displacement or major ground movement. Based on the inland location of the alignment, tsunamis do not pose a hazard to this site.

Seiches: Seiches are large waves generated in enclosed bodies of water in response to ground shaking. The alignment along San Timoteo Canyon Road runs adjacent to a few small lakes. In this area, there may be risk of flooding due to seiching. Along other areas of the alignment, the risk of flooding due to seiching is considered low.

Earthquake-Induced Flooding: Dams or other water-retaining structures may fail as a result of large earthquakes, resulting in flooding. San Bernardino County has designated the Santa Ana River as a dam inundation zone in the vicinity of the pipeline crossing.

There is a potential for flood waters to affect the alignment in that area in the event of a breach of the Seven Oaks or Big Bear Lake dams due to an earthquake. Due to the distance of the remainder of the alignment from any large dams or other water-retaining structures, the risk for earthquake-induced flooding is considered low.

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8.0 EARTHWORK RECOMMENDATIONS

Recommendations for earthwork associated with pipe trenching, bore and jack, and HDD methods are presented in the following subsections.

8.1 General

Earthwork for the project will include trench excavation, pipe subgrade preparation, pipeline bedding placement, trench backfill following the placement of the pipe segment, and excavation and backfill of bore-and-jack pits.

Deleterious material, including organics, asphalt, and debris generated during excavation should not be placed as backfill.

Migration of fines from the surrounding native soils, in the case of water leaks from the pipe, must be considered in selecting the gradation of the materials placed within the trench, including bedding, pipe zone and trench zone backfill, a s defined in the following sections. Such migration of fines may deteriorate pipe support and may result in settlement/ground loss at the surface.

8.2 Pipeline Subgrade Preparation

The final subgrade surface should be level, firm, uniform, free of loose materials, and properly graded to provide uniform bearing and support to the entire section of the pipe placed on bedding material. Protruding oversize particles, larger than 3 inches in dimension, if any, should be removed from the trench bottom and repl aced with compacted on-site materials.

Any loose, soft and/or unsuitable materials encountered at the pipe su b-grade should be removed and replaced with an adequate bedding material.

During the digging of depressions for proper sealing of the pipe joints , the pipe should rest on a prepared bottom for as near its full length as is practicable.

8.3 Pipe Bedding

Bedding is defined as the material supporting and surrounding the pipe to 12 inches above the pipe. The load on the rigid pipes and deflection of flexible pipes and, hence, the pipe design, depends on the type and the amount of bedding placed underneath and around the pipe. Care should be taken to densify the bedding material below the springline of the pipe.

Pipe design generally requires a granular material with a sand equivalent (SE) greater than 30. Only two of the seven tested soil samples were above 30. The excavated

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alignment soils may not be suitable for use as pipe bedding. Excavated site soils should be tested to determine their sand equ ivalent before being used as bedding or imported material with SE>30 should be used.

Migration of fines from the surrounding soils must be considered in selecting the gradation of any imported bedding material. To avoid migration of fines if coarse beddin g material is utilized, commercially available geofabric used for filtration purposes (such as Mirafi 140N, or equivalent) may be wrapped around the bedding material encasing the pipe to separate the bedding material from the surrounding native or fill soi ls.

8.4 Trench Zone Backfill

The trench zone is defined as the portion of the trench above the pipe bedding extending up to the final grade level of the trench surface. Excavated site soils free of oversize particles and deleterious matter may be used t o backfill the trench zone. Detailed trench backfill recommendations are provided below.

• Trench excavations to receive backfill should be free of trash, debris or other unsatisfactory materials at the time of backfill placement.

• Trench zone backfill should be compacted to at least 90 percent of the laboratory maximum dry density as per ASTM D1557 test method . At least the upper 1 foot of trench backfill underlying pavement should be compacted to at least 95 percent of the laboratory maximum dry density as per ASTM D1557 test method.

• Particles larger than 1 inch should not be placed within 12 inches of the pavement subgrade. No more than 30 percent of the backfill volume should be larger than ¾-inch in the largest dimension. Gravel should be well mixed with finer soil. Rocks larger than 3 inches in the largest dimension should not be placed as trench backfill.

• Trench backfill should be compacted by mechanical methods, such as sheepsfoot, vibrating or pneumatic rollers or mechanical tampers to achieve the density specified herein. The backfill materials should be brought to within  3 percent of optimum moisture content for coarse-grained soil, and between optimum and 2 percent above optimum for fine-grained soil, then placed in horizontal layers. The thickness of uncompacted layers should not exceed 8 inches. Each layer should be evenly spread, moistened or dried as necessary, and then tamped or rolled until the specified density has been achieved.

• The contractor should select the equipment and processes to be used to achieve the specified density without damage to adjacent ground, structures, utilities and completed work.

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• The field density of the compacted soil should be measured by the ASTM Standard D1556 (Sand Cone) or ASTM D6938 (Nuclear Gauge) or equivalent.

• Observations and field tests should be performed by the project soils consultant to confirm that the required degree of compaction has been obtained. Where compaction is less than that specified, additional compactive effort should be made with adjustment of the moisture content as necessary, until the specified compaction is obtained.

• It should be the responsibility of the contractor to maintain safe working conditions during all phases of construction.

• Trench backfill should not be placed, sprea d or rolled during unfavorable weather conditions. When the work is interrupted by heavy rain, fill operations should not resume until field tests by the project’s geotechnical consultant indicate that the moisture content and density of the fill are in co mpliance with project specifications.

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9.0 DESIGN RECOMMENDATIONS

General design recommendations, resistance to lateral loads, pipe design parameters, bearing pressures, and soil corrosivity are discussed in the following subsections.

9.1 General

Where pipelines connect to rigid structures and are subjected to significant loads as the backfill is placed to finish grade, we recommend that provisions be incorporated in the design to provide support of these pipelines where they exit the structures. Cons ideration can be given to flexible connections, concrete slurry support beneath the pipes where they exit the structures, overlaying the pipes with a few inches of compressible material, (i.e. Styrofoam, or other materials), or other techniques.

The various design recommendations provided in this section are based on the assumption that the above earthwork recommendations will be implemented.

9.2 Resistance to Lateral Loads

Resistance to lateral loads can be assumed to be provided by passive earth pres sures and friction between construction materials and native soils. The resistance to lateral loads were estimated by using on-site native soils strength parameters obtained from laboratory testing. The resistance to lateral loads recommended for use in de sign of the thrust blocks are presented in the following table.

Table No. 8, Resistance to Lateral Loads
Lateral Resistance Soil
Parameters
BH-01
through
BH-04
BH-05
through
BH-08
BH-09
through
BH-14
BH-15
through
BH-21
BH-22
through
BH-26
BH-27
through
BH-34
BH-35
through
BH-38
Passive earth pressure (psf per
foot of depth) 310 250 240 240 240 200 230
Maximum allowable bearing
pressure against native soils
(psf)
3,000 2,000 2,500 1,500 1,500 2,000 2,500
Coefficient of friction between
formed concrete and native
soils, fs (degree)

0.35 0.25 0.25 0.30 0.35 0.30 0.30

9.3 Soil Parameters for Pipe Design

Structural design requires proper evaluation of all possible loads acting on pipes and structures. The stresses and strains induced on buried pipes and walls depend on many factors, including the type of soil, density, bearing pressure, angle of internal friction, coefficient of passive earth pressure, and coefficient of friction at the interface between the backfill and native soils. The recommended value s of the various soil parameters for design are provided in the following table.

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Table No. 9, Soil Parameters for Pipe Design
Soil Parameters
Parameters
BH-01
through
BH-04
BH-05
through
BH-08
BH-09
through
BH-14
BH-15
through
BH-21
BH-22
through
BH-26
BH-27
through
BH-34
BH-35
through
BH-38
Average compacted fill total unit
weight,  (pcf) 130 125 133 129 127 129 129
Angle of internal friction of soils,  35 30 29 29 29 24 28 Soil cohesion, c (psf) 200 30 110 10 10 160 120
Coefficient of friction between
concrete and native soils, fs
(degree)

0.35 0.25 0.25 0.30 0.35 0.30 0.30
Coefficient of friction between steel
or PVC pipe and native soils, fs
(degree)

0.25 0.20 0.20 0.25 0.30 0.25 0.25
Bearing pressure against native
soils (psf) 3,000 2,000 2,500 1,500 1,500 2,000 2,500
Coefficient of passive earth
pressure, Kp 3.69 3.00 2.77 2.88 2.88 2.37 2.77
Coefficient of active earth pressure,
Ka 0.27 0.33 0.36 0.35 0.35 0.42 0.36
Modulus of Soil Reaction E’ (psi) 2,000 1,500 1,500 2,000 2,000 1,500 1,500

9.4 Bearing Pressure for Anchor and Thrust Blocks

An allowable net bearing pressure presented in Table No. 9, Soil Parameters for Pipe Design may be used for anchor and thrust block design against alluvial soils. Such thrust blocks should be at least 18 inches wide.

If normal code requirements are applied for design, the above recommended bearing capacity and passive resistances may be increased by 33 percent for short duration loading such as seismic or wind loading.

9.5 Pipeline Fault Crossings

The pipeline alignment crosses the San Jacinto Fault Zone and the Beaumont Plain Fault Zone as discussed in Section 7.1, Faulting. The pipeline within the fault zone is subject to risk of damage and displacement due to ground surface rupture during a seismic event. The movement may be concentrated in a single strand or may be spread across several fault strands in a zone several meters or tens of meters wide.

The potential for failure of the pipelines in this vicinity due to small fault displacements may be reduced by using enhancements such as, but not limited to, flexible pipe

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materials, flexible couplers, or continuously welded pipe. Large fault displacements from a large seismic event will likely cause a pipe failure.

9.6 Soil Corrosivity

The results of chemical testing of representative samples of site soils were evaluated for corrosivity evaluation with respect to common construction materials such as concrete and steel. The test results are presented in Appendix B, Laboratory Testing Program in Table No. B-3, Summary of Corrosivity Test Results, and are discussed below.

The sulfate content of the majority of the soils along the proposed alignment correspond to American Concrete Institute (ACI) exposure category S0 for this sulfate concentration (ACI 318-11, Table 4.2.1). ACI recommends a minimum compressive strength of 2,500 psi for exposure category S0 in ACI 318-11, Table 4.3.1. No concrete type restrictions are specified.

We anticipate that concrete structures such as vaults will be exposed to moi sture from precipitation and irrigation. Based on the alignment location and the results of chloride testing of the site soils, we do not anticipate that concrete structures will be exposed to external sources of chlorides, such as deicing chemicals, salt, brackish water, or seawater. ACI specifies exposure category C1 where concrete is exposed to moisture, but not to external sources of chlorides (ACI 318 -11, Table 4.2.1). ACI provides concrete design recommendations in ACI 318-11, Table 4.3.1, including a minimum compressive strength of 2,500 psi, and a maximum chloride content of 0.3 percent.

The measured value of the minimum electrical resistivity when saturated ranged from 1,400 to 4,600 Ohm-cm. This indicates that the majority of the soils along the p roposed alignment are corrosive for ferrous m etals in contact with the soil (Romanoff, 1957).

Converse does not practice in the area of corrosion consulting. A qualified corrosion consultant should be consulted to provide appropriate corrosion mitigation measures for ferrous metals in contact with the site soils.

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10.0 CONSTRUCTION RECOMMENDATIONS

10.1 General

Prior to the start of construction, all existing underground utilities should be located along the pipeline alignment. Such utilities should eithe r be protected in-place, or removed and replaced during construction as required by the project specifications.

Vertical braced excavations are feasible along the pipeline alignment. Sloped excavations may not be feasible in locations adjacent to existin g utilities or structures, including bore-and-jack pits adjacent to existing pavement, utilities, channels, railroad easements, or other improvements. Recommendations pertaining to temporary excavations are presented in this section.

Where the side of the excavation is a vertical cut, it should be adequately supported by temporary shoring to protect workers and any adjacent structures.

All applicable requirements of the California Construction and General Industry Safety Orders, the Occupational Safety and Health Act, current amendments, and the Construction Safety Act should be met. The soils exposed in cuts should be observed during excavation by the owner’s representative. If potentially unstable soil conditions are encountered, modifications of slope ratios for temporary cuts may be required.

10.2 Temporary Sloped Excavations

Temporary open-cut trenches may be constructed with side slopes as recommended in the following table. Temporary cuts encountering soft and wet fine -grained soils; dry loose, cohesionless soils or loose fill from trench backfill may have to be constructed at a flatter gradient than presented below. The final determination of temporary slope gradients should be based on review of the encountered soils by a competent person employed by the contractor, in accordance with Section 1541 of the OSHA Construction Safety Orders.

Table No. 10, Slope Ratios for Temporary Excavations
Soil Type Depth of Cut (feet) Recommended Maximum Slope (Horizontal:Vertical)¹
Clay, Silt, Clayey Sand, Silty
Sand
0-4 Vertical
4-10 1:1
Sand 0-4 1.5:1
4-10 1.5:1
¹ Slope ratio is assumed to be constant from top to toe of slope, with level adjacent ground.

Loose sand layers were encountered in borings BH-8, BH-21, BH-22, BH-30, BH-34, BH- 35, and BH-36. Some unstable soil should be anticipated in the vicinity of these borings.

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For steeper temporary construction slopes or deeper excavations, or unstable soil encountered during the excavation, shoring or trench shields should be provided by the contractor as necessary to protect the workers in the excavation.

Surfaces exposed in sloped excavations should be kept moist but not saturated to retard raveling and sloughing during construction. Adequate provisions should be made to protect the slopes from erosion during periods of rainfall. Surcharge loads, including construction materials, should not be placed within 5 feet of the unsupported slope edge.

Stockpiled soils with a height higher than 6 feet will require greater distance from trench edges.

10.3 Shoring Design

Temporary shoring will be required where open sloped excavations will not be feasible due to unstable soils or due to nearby existing structures or facilities. Temporary shoring may consist of conventional soldier piles and lagging or sheet piles. The shoring for the pipe excavations may be laterally supported by walers and cross bracing or may be cantilevered. Drilled excavations for soldier piles will require the use of drilling fluids to prevent caving and to maintain an opened hole for pile in stallation.

The active earth pressure behind any shoring depends primarily on the allowable movement, type of backfill materials, backfill slopes, wall inclination, surcharges, and any hydrostatic pressures.

The lateral earth pressures to be used in the design of shoring is presented in the following table.

Table No. 11, Lateral Earth Pressures for Temporary Shoring Lateral Resistance Soil
Parameters*
BH-01
through
BH-04
BH-05
through
BH-08
BH-09
through
BH-14
BH-15
through
BH-21
BH-22
through
BH-26
BH-27
through
BH-34
BH-35
through
BH-38
Active Earth Pressure (Braced
Shoring) (psf) (A) 23 28 32 30 29 36 31
Active Earth Pressure (Cantilever
Shoring) (psf) (B) 36 42 48 45 45 55 47
At-Rest Earth Pressure (Cantilever
Shoring) (psf) (C) 56 69 71 67 66 77 69
Passive earth pressure (psf per
foot of depth) (D) 310 250 240 240 240 200 230
Maximum allowable bearing
pressure against native soils (psf)
(E)
3,000 2,000 2,500 1,500 1,500 2,000 2,500
Coefficient of friction between
sheet pile and native soils, fs
(degree) (F)

0.25 0.20 0.20 0.25 0.30 0.25 0.25
* Parameters A through F are used in Figures No. 7 and 8 below.

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Restrained (braced) shoring systems should be designed based on Figure No. 7, Lateral Earth Pressure for Braced Excavation to support a uniform rectangular lateral earth pressure.

Figure No. 7, Lateral Earth Pressures for Temporary Braced Excavation

Unrestrained (cantilever) design of cantilever shoring consisting of soldier piles spaced at least two diameters on-center or sheet piles, can be based on Figure No. 8, Lateral Earth Pressures on Temporary Cantilever Wall.

Figure No. 8, Lateral Earth Pressures on Temporary Cantilever Wall

Note:

All values of height (H) in feet, pressure (P) and surcharge (q) in pounds per square foot (psf).

Total Earth Pressure, P

P = Pq + Pa

Pq = 0.5q - incremental surcharge pressure

Pa = (A)H1 - active earth pressure (Braced walls)

Lateral Pressure Resistance

Pp = (D) H2 ≤ (E) psf - passive earth pressure (on native soils)

µ = (F) - ultimate friction coefficient between steel
sheet piles and soil

Total Earth Pressure, P

P = Pq + Pa, Po

Pq = 0.5q - incremental surcharge pressure

Pa = (B)H1 - active earth pressure (Un-restrained)

Po = (C)H1 - at rest earth pressure (Restrained)

Lateral Pressure Resistance

Pp = (D) H2 ≤ (E) psf - passive earth pressure (on native soils)

µ = (F) - ultimate friction coefficient between steel sheet piles and soil

Note:

All values of height (H) in feet, pressure (P) and surcharge (q) in pounds per square foot (psf).

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Earth pressures assume no hydrostatic pressures. If hydrostatic pressures are allowed to build up, the incremental earth pressures below the ground -water level should be reduced by 50 percent and added to hydrostatic pressure for total lateral pressure.

Passive resistance includes a safety factor of 1.5 . The upper 1 foot for passive resistance should be ignored unless the surface is confined by a pavement or slab.

In addition to the lateral earth pressure, surcharge pressures due to miscellaneous loads, such as soil stockpiles, vehicular traffic or construction equipment located adjacent to the shoring, should be included in the design of the shoring. A uniform lateral pressure of 100 psf should be included in the upper 10 feet of the shoring to account for normal vehicular and construction traffic within 10 feet of the trench excavation. As previously mentioned, all shoring should be designed and installed in accordance with state and federal safety regulations.

The contractor should have provisions for soldier pile and sheet pile removal. All voids resulting from removal of shoring should be filled. The method for filling voids should be selected by the contractor, depending on construction conditions, void dimensions and available materials. The acceptable materials, in general, should be non -deleterious, and able to flow into the voids created by shoring removal (e.g. concrete slurry, “pea” gravel, etc.).

Excavations for the proposed pipeline should not extend below a 1:1 horizontal:vertical (H:V) plane extending from the bottom of any existing struct ures, utility lines or streets.

Any proposed excavation should not cause loss of bearing and/or lateral supports of the existing utilities or streets.

If the excavation extends below a 1:1 (H:V) plane extending from the bottom of the existing structures, utility lines or streets, a maximum of 10 feet of slope face parallel to the existing improvement should be exposed at a time to reduce the potential for instability. Backfill should be accomplished in the shortest period of time and in alternating sections.

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11.0 GEOTECHNICAL SERVICES DURING CONSTRUCTION

The project geotechnical consultant should be present to observe conditions and test the density and moisture of the backfill. The excavations and backfill should be observed and tested for compliance with project specifications.

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12.0 CLOSURE

This report is prepared for the project described herein and is intended for use solely by Albert A. Webb Associates and its authorized agents, to assist in the design and construction of the proposed pipeline and HDD/bore-and-jack project. Our findings and recommendations were obtained in accordance with generally accepted professional principles practiced in geotechnical engineering. We make no other warranty, either expressed or implied.

Our conclusions and recommendations are based on the results of the field investigations and laboratory tests, combined with interpolation and extrapolation of soil conditions between and beyond the boring locations. Site exploration identifies actual soil conditions only at those points where samples are taken, when they are taken. Data derived through sampling and laboratory testing is extrapolated by Converse employees who render an opinion about the overall soil conditions. Actual conditions in areas not sampled may differ. In the event that changes to the project occur, or additional, relevant information about the project is brought to our attention, the recommendations contained in this report may not be valid unless these changes and additional relevant information are reviewed and the recommendations of this report are modified or verified in writing.

In addition, the recommendations can only be finalized by observing actual subsurface conditions revealed during construction. Converse Consultants is not responsible or liable for any claims or damages associated with interpretation of available information provided to others.

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13.0 REFERENCES

AMERICAN CONCRETE INSTITUTE (ACI), 2011, Building Code Requirements for Structural Concrete (ACI 318-11) and Commentary, first printing August 2011.

AMERICAN SOCIETY OF CIVIL ENGINEERS (ASCE), 2010, Minimum Design Loads for Buildings and Other Structures, SEI/ASCE Standard No. 7-10, dated January 1, 2010.

BLAKE, T. F., 2000, EQFAULT, Computer Programs for Performing Probabilistic, and Seismic Coefficient Analysis and Historical Earthquake Search.

CALIFORNIA BUILDING STANDARDS COMMISSION (CBSC), 2013, California Building Code (CBC).

CALIFORNIA DEPARTMENT OF TRANSPORTATION (Caltrans), 1996, Trenching and Shoring Manual, Revision II, dated January 1990, revised December 1996.

CALIFORNIA GEOLOGICAL SURVEY (formerly California Division of Mines and Geology), 1974, Special Studies Zones, Sunnymead Quadrangle, California, scale 1:24,000, dated July 1, 1974.

CALIFORNIA GEOLOGICAL SURVEY (formerly California Division of Mines and Geology), 1977a, Special Studies Zones, Redlands Quadrangle, California, scale 1:24,000, dated January 1, 1977.

CALIFORNIA GEOLOGICAL SURVEY (formerly California Division of Mines and Geology), 1977b, Special Studies Zones, San Bernardino South Quadrangle, California, scale 1:24,000, dated January 1, 1977.

CALIFORNIA GEOLOGICAL SURVEY (formerly California Division of Mines and Geology), 1995a, Special Studies Zones, Beaumont Quadrangle, California, scale 1:24,000, dated June 1, 1995.

CALIFORNIA GEOLOGICAL SURVEY (formerly California Division of Mines and Geology), 1995b, Special Studies Zones, El Casco Quadrangle, California, scale 1:24,000, dated June 1, 1995.

CALIFORNIA GEOLOGICAL SURVEY (CGS), 2007, Fault-Rupture Hazard Zones in California, Alquist-Priolo Earthquake Faulting Zoning Act with Index to Earthquake Fault Zone Maps, Special Publication 42, revised 2007.

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CALIFORNIA GEOLOGICAL SURVEY (CGS), 2008, Guidelines for Evaluating and Mitigating Seismic Hazards in California, Special Publication 117A, dated September 11, 2008.

CALIFORNIA STATE WATER RESOURCES CONTROL BOARD (SWRCB), 2017, GeoTracker database ( http://geotracker.waterboards.ca.gov/) , accessed in May 2017.

CAO, T., et al., 2003, The Revised 2002 California Probabilistic Seismic Hazard Maps, ( http://www.consrv.ca.gov/cgs/rghm/psha/fault_parameters/pdf/Documents/2002_ CA_Hazard_Maps.pdf), dated June 2003.

DIBBLEE, T.W., and MINCH, J.A., 2003, Geologic Map of the Beaumont quadrangle, Riverside County, California: Dibblee Geological Foundation, Dibblee Foundation Map DF-114, scale 1:24,000

DIBBLEE, T.W., and MINCH, J.A., 2003, Geologic Map of the El Casco quadrangle, Riverside County, California: Dibblee Geological Foundation, Dibblee Foundat ion Map DF-113, scale 1:24,000

DIBBLEE, T.W., and MINCH, J.A., 2003, Geologic Map of the Riverside East/south 1/2 of San Bernardino South quadrangles, San Bernardino and Riverside County, California: Dibblee Geological Foundation, Dibblee Foundation Map D F-109, scale 1:24,000

DIBBLEE, T.W., and MINCH, J.A., 2003, Geologic Map of the Sunnymead/south 1/2 of Redlands quadrangles, San Bernardino and Riverside County, California: Dibblee Geological Foundation, Dibblee Foundation Map DF-110, scale 1:24,000

DIBBLEE, T.W., and MINCH, J.A., 2004, Geologic map of the San Bernardino North/north 1/2 of San Bernardino South quadrangles, San Bernardino and Riverside County, California: Dibblee Geological Foundation, Dibblee Foundation Map DF-127, scale 1:24,000.

HOWARD, Amster, Pipe Installation, Relativity Publishing, 2002. Lakewood, CO.

MORTON, D.M. and MILLER, F.K., 2006, Geologic Map of the San Bernardino and Santa Ana 30' x 60' Quadrangles, California, U.S. Geological Survey Open -File Report 2006-1217, scale 1:100,000.

PUBLIC WORKS STANDARDS, INC., 2015, Standard Specifications for Public Works Construction (“Greenbook”), 2015.

Geotechnical Investigation Report for the Brine Disposal Pipeline Cities of Beaumont, Redlands, Loma Linda, and San Bernardino Riverside and San Bernardino Counties, California
May 30, 2017

Copyright 2017 Converse Consultants
Converse Project No. 16-81-255-02 31

RIVERSIDE COUNTY, 2017, Riverside County GIS - Map My County ( http://mmc.rivcoit.org/mmc_public) , accessed in May 2017.

ROMANOFF, MELVIN, 1957, Underground Corrosion, National Bureau of Standards Circular 579, dated April 1957.

SAN BERNARDINO COUNTY, 2010a, San Bernardino County General Plan Hazard Overlays, Map Sheet FH30B, scale 1:24,000, dated March 9, 2010.

SAN BERNARDINO COUNTY, 2010b, San Bernardino County General Plan Geologic Hazard Overlays, Map Sheet FH30C, scale 1:24,000, dated March 9, 2010.

SAN BERNARDINO COUNTY, 2010c, San Bernardino County General Plan Hazard Overlays, Map Sheet FH31B, scale 1:24,000, dated March 9, 2010 .

SAN BERNARDINO COUNTY, 2010d, San Bernardino County General Plan Geologic Hazard Overlays, Map Sheet FH31C, scale 1:24,000, dated March 9, 2010.

U.S. GEOLOGICAL SURVEY (USGS), 2017a, National Water Information System: Web Interface ( http://nwis.waterdata.usga.gov/nwis/gwlevels) , accessed in May 2017.

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Appendix A

Field Exploration

Geotechnical Investigation Report for the Brine Disposal Pipeline Cities of Beaumont, Redlands, Loma Linda, and San Bernardino Riverside and San Bernardino Counties, California
May 30, 2017

Copyright 2017 Converse Consultants
Converse Project No. 16-81-255-02 A-1

APPENDIX A: FIELD EXPLORATION

Our field investigation included site reconnaissance and a subsurface exploration program consisting of drilling soil borings. During the site reconnaissance, the surface conditions were noted and the boring locations were marked at locations selected by Albert A. Webb Associates using nearby landmarks as a guide. The boring locations should be considered accurate only to the degree implied by the method used to mark them in the field.

Thirty exploratory borings were drilled between March 20 and March 23, 2017 to depths ranging from 1.2 to the maximum planned depth of 16.5 feet below existing ground surface (bgs).

The borings were advanced using a truck-mounted drill rig equipped with 8-inch diameter hollow-stem augers for soil sampling. Encountered earth materials were continuously logged by a Converse engineer and visually classified in the field in accordance with the Unified Soil Classification System. Where appropriate, field descriptions and classifications have been modified to reflect laboratory test results.

Relatively undisturbed samples were obtained using California Modified Samplers (2.4 inches inside diameter and 3 inches outside diameter) lined with thin sample rings. The steel ring sampler was driven into the bottom of the borehole with successive drop s of a 140-pound driving weight falling 30 inches. Blow counts at each sample interval are presented on the boring logs. Samples were retained in brass rings (2.4-inches inside diameter and 1 inch in height) and carefully sealed in waterproof plastic conta iners for shipment to the Converse laboratory. Bulk samples of typical soil types were also obtained.

The exact depths at which material changes occur cannot always be established accurately. Unless a more precise depth can be established by other means, changes in material conditions that occur between driven samples are indicated in the log at the top of the next drive sample.

Following the completion of logging and sampling, all borings were backfilled with soil cuttings and lightly tamped. As a result, the surface may settle over time. If construction is delayed, we recommend the owner monitor the boring locations and backfill any depressions that might occur, or provide protection around the boring locations to prevent trip and fall injuries from occurring near the area of any potential settlement.

Where the borings penetrated pavement, the surface was patched with cold asphalt concrete.

For a key to soil symbols and terminology used in the boring logs, refer to Drawing No. A- 1, Unified Soil Classification and Key to Boring Log Symbols . Logs of the exploratory borings are presented in Drawings No. A-2 through 31, Logs of Borings.