Agenda packet, regular meeting, first session — Rancho Mirage City Council, July 17, 2025 (part 2 of 5)

0.00 0.00
< 0.005
CO2e
134

0.00 9.96

0.00 1.65

0.00 260

0.00 0.00

20.7 Vendor

0.00 0.00

0.00 007
25/51

0.00 0.00

0.00 Rancho Mirage Affordable Housing Family Apartments Detailed Report, 4/7/2025 Hauling
Annual
Worker
Vendor
Hauling

0.00 < 0.005

0.00 0.00

0.00 < 0.005

0.00 0.00

0.00 0.02

0.00 0.00

0.00 < 0.005

0.00 0.00

0.00 < 0.005

0.00 0.00

0.00 3.43

0.00 0.00

3.25. Architectural Coating (2029) - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Location
Onsite
Daily, Summer (Max)
Daily, Winter (Max)
Off -Road Equipment
Architectural Coatings
Onsite truck
Average Daily
Off -Road Equipment
Architectural Coatings
Onsite truck
Annual
Off -Road Equipment
Architectural Coatings
Onsite truck
Offsite
Daily, Summer (Max)
Daily, Winter (Max)
Worker
ROG

0.10 1.47

0.00 0.01

0.09 0.00
< 0.005

0.02 0.00

0.06 NOx

0.79 0.00

0.05 0.00

0.01 0.00

0.08 CO

0.00 0.07

0.00 0.01

0.00 0.88
SO2
< 0.005

0.00 < 0.005

0.00 0.00
PM10T

0.01 0.00
< 0.005

0.00 < 0.005

0.00 0.28
PM2.5T

0.01 0.00
< 0.005

0.00 < 0.005

0.00 0.07
CO2e
134

0.00 8.39

0.00 1.39

0.00 256
Vendor

0.00 0.00

0.00 298
26/51

0.00 0.00

0.00 Rancho Mirage Affordable Housing Family Apartments Detailed Report, 4/7/2025 Hauling
Average Daily
Worker
Vendor
Hauling
Annual
Worker
Vendor
Hauling

0.00 0.00 0.00

0.00 0.00

0.00 0.00
< 0.005

0.00 0.00

0.07 0.00

0.00 0.00

0.02 0.00

0.00 < 0.005

0.00 0.00
< 0.005

0.00 0.00

0.01 0.00

0.00 0.00

0.00 0.00
< 0.005

0.00 0.00

17.1 0.00

0.00 < 0.005

0.00 0.00

2.84 0.00

0.00 4. Operations Emissions Details

4.1. Mobile Emissions by Land Use

4.1.1. Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Land Use
ROG
NOx
CO
SO2
PM10T
PM2.5T
CO2e
Daily, Summer (Max)
Apartments Mid Rise 2.55
Parking Lot 0.00
Total 2.55
Daily, Winter (Max)
Apartments Mid Rise 2.11
Parking Lot 0.00
Total 2.11
Annual
Apartments Mid Rise 0.41
Parking Lot 0.00

2.89 0.00

2.89 31.0

0.00 31.0

0.08 0.00

0.08 7.23

0.00 7.23

1.87 0.00

1.87 3.14 20.6 0.07

0.00 0.00 0.00

3.14 20.6 0.07

0.55 4.36

0.00 0.00

7.23 0.00

7.23 8,489

0.00 8,489

1.87 0.00

1.87 0.01
299
27/51

1.32 0.00
7,545

0.00 7,545

0.34 1,311

0.00 0.00

Rancho Mirage Affordable Housing Family Apartments Detailed Report, 4/7/2025 Total 0.41 0.55 4.36 0.01 1.32

4.2. Energy

4.2.1. Electricity Emissions By Land Use - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual)

0.34 1,311
Land Use
ROG
NOx
CO
SO2
PM10T
PM2.5T
CO2e
Daily, Summer (Max)
Apartments Mid Rise
Parking Lot
Total
Daily, Winter (Max)
Apartments Mid Rise
Parking Lot
Total
Annual
Apartments Mid Rise
Parking Lot
Total
1,066

95.9 1,162
1,066

95.9 1,162

4.2.3. Natural Gas Emissions By Land Use - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Land Use
ROG
Daily, Summer (Max)
Apartments Mid Rise 0.03
Parking Lot 0.00
Total 0.03
Daily, Winter (Max)
NOx
CO

0.49 0.00

0.49 0.21

0.00 0.21
SO2
177

15.9 192
PM10T
< 0.005

0.00 < 0.005

0.04 0.00

0.04 PM2.5T
CO2e

0.04 0.00

0.04 622

0.00 622
3000
28/51

Rancho Mirage Affordable Housing Family Apartments Detailed Report, 4/7/2025 Apartments Mid Rise
Parking Lot
Total
Annual
Apartments Mid Rise
Parking Lot
Total

0.03 0.00

0.03 0.01

0.00 0.01

0.49 0.00

0.49 0.09

0.00 0.09

0.21 0.00

0.21 0.04

0.00 0.04
< 0.005

0.00 < 0.005
< 0.005

0.00 < 0.005

0.04 0.00

0.04 0.01

0.00 0.01

0.04 0.00

0.04 0.01

0.00 0.01
622

0.00 622
103

0.00 103

4.3. Area Emissions by Source

4.3.1. Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Source
ROG
NOx
CO
Daily, Summer (Max)
Hearths
Consumer Products
Architectural Coatings
Landscape Equipment
Total
Daily, Winter (Max)
Hearths
Consumer Products
Architectural Coatings
Total
Annual
Hearths
Consumer Products
Architectural Coatings

0.00 0.18

0.08 0.74

0.99 0.00

0.18 0.08

0.26 0.00

0.03 0.01

0.00 0.00
SO2

0.00 PM10T

0.00 0.08

8.53 < 0.005
< 0.005

0.08 8.53
< 0.005
< 0.005

0.00 0.00

0.00 0.00
PM2.5T

0.00 < 0.005
< 0.005

0.00 0.00

0.00 CO2e

0.00 22.8

22.8 0.00

0.00 0.00
JUG
29/51

Rancho Mirage Affordable Housing Family Apartments Detailed Report, 4/7/2025 Landscape Equipment 0.07

0.01 0.77
Total 0.11
< 0.005 < 0.005
< 0.005 1.86

0.01 0.77
< 0.005 < 0.005
< 0.005 1.86

4.4. Water Emissions by Land Use

4.4.1. Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Land Use
ROG
NOx
CO
SO2
PM10T
PM2.5T
CO2e
Daily, Summer (Max)
Apartments Mid Rise
Parking Lot
Total
Daily, Winter (Max)
Apartments Mid Rise
Parking Lot
Total
Annual
Apartments Mid Rise
Parking Lot
Total

90.4 0.00

90.4 90.4

0.00 90.4

15.0 0.00

15.0 4.5. Waste Emissions by Land Use

4.5.1. Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Land Use
ROG
NOx
CO
SO2
PM 10T
PM2.5T
CO2e
Daily, Summer (Max) —
Apartments Mid Rise —
302
30/51
209

Rancho Mirage Affordable Housing Family Apartments Detailed Report, 4/7/2025 Parking Lot
Total
Daily, Winter (Max)
Apartments Mid Rise
Parking Lot
Total
Annual
Apartments Mid Rise
Parking Lot
Total

0.00 209
209

0.00 209

34.7 0.00

34.7 4.6. Refrigerant Emissions by Land Use

4.6.1. Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Land Use
Daily, Summer (Max)
Apartments Mid Rise
Total
Daily, Winter (Max)
Apartments Mid Rise
Total
Annual
Apartments Mid Rise
Total
ROG
NOx
CO
SO2
PM10T
PM2.5T
CO2e

0.06 0.06

0.01 0.01

4.7. Offroad Emissions By Equipment Type
303
31 / 51

Rancho Mirage Affordable Housing Family Apartments Detailed Report, 4/7/2025

4.7.1. Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Equipment Type
ROG
NOx
CO
SO2
PM10T
PM2.5T
CO2e
Daily, Summer (Max)
Total
Daily, Winter (Max)
Total
Annual
Total

4.8. Stationary Emissions By Equipment Type

4.8.1. Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Equipment Type
ROG
NOx
CO
SO2
PM10T
PM2.5T
CO2e
Daily, Summer (Max)
Total
Daily, Winter (Max)
Total
Annual
Total

4.9. User Defined Emissions By Equipment Type

4.9.1. Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Equipment Type
ROG
NOx
CO
SO2
PM10T
PM2.5T
CO2e
Daily, Summer (Max) —
30-4
32/51

Rancho Mirage Affordable Housing Family Apartments Detailed Report, 4/7/2025 Total
Daily, Winter (Max)
Total
Annual
Total

4.10. Soil Carbon Accumulation By Vegetation Type

4.10.1. Soil Carbon Accumulation By Vegetation Type - Unmitigated Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Vegetation
ROG
NOx
CO
SO2
PM10T
PM2.5T
CO2e
Daily, Summer (Max)
Total
Daily, Winter (Max)
Total
Annual
Total

4.10.2. Above and Belowground Carbon Accumulation by Land Use Type - Unmitigated Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Land Use
ROG
NOx
CO
SO2
PM10T
PM2.5T
CO2e
Daily, Summer (Max)
Total
Daily, Winter (Max)
Total
Annual
Total
305
33/51

Rancho Mirage Affordable Housing Family Apartments Detailed Report, 4/7/2025

4.10.3. Avoided and Sequestered Emissions by Species - Unmitigated Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Species
Daily, Summer (Max)
Avoided
Subtotal
Sequestered
Subtotal
Removed
Subtotal
Daily, Winter (Max)
Avoided
Subtotal
Sequestered
Subtotal
Removed
Subtotal
Annual
Avoided
Subtotal
Sequestered
Subtotal
Removed
Subtotal
ROG
NOx
CO
SO2
PM10T
PM2.5T
CO2e
306
34/51

Rancho Mirage Affordable Housing Family Apartments Detailed Report, 4/7/2025

5. Activity Data

5.1. Construction Schedule
Phase Name
Phase Type
Start Date
End Date
Days Per Week
Work Days per Phase
Phase Description
Linear, Grubbing & Land
Clearing
Linear, Grubbing & Land 2/1/2027
Clearing
Linear, Grading &
Excavation
Linear, Grading &
Excavation
Linear, Drainage, Utilities,
& Sub -Grade
2/12/2027

5.00 10.0
2/13/2027
3/12/2027

5.00 20.0
—
Linear, Drainage, Utilities, 3/13/2027
& Sub -Grade
Linear, Paving
Site Preparation
Grading
Building Construction
Paving
Architectural Coating
Linear, Paving
Site Preparation
Grading
Building Construction
Paving
Architectural Coating
4/17/2027
3/12/2027
4/9/2027
6/18/2027
11/15/2028
11/24/2028
4/16/2027

5.00 25.0
6/11/2027
4/8/2027
6/17/2027
1/18/2029
1/2/2029
2/1/2029

5.00 5.00

40.0 20.0

50.0 415

35.0 50.0

5.2. Off -Road Equipment

5.2.1. Unmitigated
Phase Name
Equipment Type
Fuel Type
Engine Tier
Number per Day
Hours Per Day
Horsepower
Load Factor
Linear, Grubbing &
Land Clearing
Crawler Tractors
Diesel
Average

1.00 7.00

87.0 0.43
Linear, Grubbing &
Land Clearing
Excavators
Diesel
Average

1.00 7.00

36.0 0.38
Linear, Grubbing &
Land Clearing
Signal Boards
Electric
Average

1.00 7.00

6.00 0.82
Linear, Grading &
Excavation
Crawler Tractors
Diesel
Average

1.00 7.00

87.0 0.43
307
35/51

Rancho Mirage Affordable Housing Family Apartments Detailed Report, 4/7/2025 Linear, Grading & Excavators Diesel Average 3.00
Excavation
Linear, Grading & Graders Diesel Average 1.00
Excavation
Linear, Grading & Rollers Diesel Average 2.00
Excavation
Linear, Grading & Rubber Tired Loaders Diesel Average 1.00 Excavation
Linear, Grading & Scrapers Diesel Average 2.00
Excavation
Linear, Grading & Signal Boards Electric Average 1.00
Excavation
Linear, Grading & Tractors/Loaders/Back Diesel Average 2.00 Excavation hoes
Linear, Drainage, Air Compressors Diesel Average 1.00
Utilities, & Sub -Grade
Linear, Drainage, Generator Sets Diesel Average 1.00
Utilities, & Sub -Grade
Linear, Drainage, Graders Diesel Average 1.00
Utilities, & Sub -Grade
Linear, Drainage, Plate Compactors Diesel Average 1.00
Utilities, & Sub -Grade
Linear, Drainage, Pumps Diesel Average 1.00
Utilities, & Sub -Grade
Linear, Drainage, Rough Terrain Forklifts Diesel Average 1.00 Utilities, & Sub -Grade
Linear, Drainage, Scrapers Diesel Average 2.00
Utilities, & Sub -Grade
Linear, Drainage, Signal Boards Electric Average 1.00
Utilities, & Sub -Grade
Linear, Drainage, Tractors/Loaders/Back Diesel Average 2.00 Utilities, & Sub -Grade hoes

7.00 7.00

7.00 5.00

7.00 7.00

5.00 7.00

7.00 7.00

7.00 5.00

36.0 148

36.0 150
423

6.00 84.0

37.0 14.0
148

8.00 11.0

96.0 423

6.00 84.0
Linear, Paving
Pavers Diesel Average
Linear, Paving
Paving Equipment Diesel Average

1.00 3018.00
36/51

7.00 81.0

0.38 0.41

0.38 0.36

0.48 0.82

0.37 0.48

0.74 0.41

0.43 0.74

0.40 0.48

0.82 0.37

0.42 5.00

89.0 0.36

Rancho Mirage Affordable Housing Family Apartments Detailed Report, 4/7/2025 Linear, Paving
Linear, Paving
Linear, Paving
Site Preparation
Site Preparation
Site Preparation
Grading
Grading
Grading
Grading
Grading
Building Construction
Building Construction
Building Construction
Building Construction
Building Construction
Paving
Paving
Paving
Architectural Coating
Rollers
Signal Boards
Tractors/Loaders/Back
hoes
Rubber Tired Dozers
Tractors/Loaders/Back
hoes
Other Construction
Equipment
Excavators
Graders
Rubber Tired Dozers
Tractors/Loaders/Back
hoes
Other Construction
Equipment
Cranes
Forklifts
Generator Sets
Tractors/Loaders/Back
hoes
Welders
Pavers
Paving Equipment
Rollers
Air Compressors
Diesel Average 3.00
Electric Average 1.00
Diesel Average 2.00

7.00 7.00

5.00 Diesel Average 3.00
Diesel Average 4.00
Diesel Average 1.00
Diesel Average 1.00
Diesel Average 1.00
Diesel Average 1.00
Diesel Average 3.00

7.00 5.00

36.0 6.00

84.0 0.38

0.82 0.37
367

84.0 3.00
150

0.40 0.37

0.42 7.00

7.00 7.00

5.00 Diesel Average 1.00

3.00 36.0
148
367

84.0 0.38

0.41 0.40

0.37 150
Diesel Average 1.00
Diesel Average 3.00
Diesel Average 1.00
Diesel Average 3.00
Diesel Average 1.00
Diesel Average 2.00
Diesel Average 2.00
Diesel Average 2.00
Diesel Average 1.00

7.00 5.00

0.42 367

82.0 14.0

84.0 0.29

0.20 0.74

0.37 7.00

7.00 5.00

7.00 6.00

46.0 81.0

89.0 36.0

37.0 5.3. Construction Vehicles

5.3.1. Unmitigated

0.45 0.42

0.36 0.38

0.48 309
37/51

Rancho Mirage Affordable Housing Family Apartments Detailed Report, 4/7/2025 Phase Name
Site Preparation
Site Preparation
Site Preparation
Site Preparation
Site Preparation
Grading
Grading
Grading
Grading
Grading
Building Construction
Building Construction
Building Construction
Building Construction
Building Construction
Paving
Paving
Paving
Paving
Paving
Architectural Coating
Architectural Coating
Architectural Coating
Architectural Coating
Architectural Coating
Linear, Grubbing & Land Clearing
Linear, Grubbing & Land Clearing
Trip Type
Worker
Vendor
Hauling
Onsite truck
Worker
Vendor
Hauling
Onsite truck
Worker
Vendor
Hauling
Onsite truck
Worker
Vendor
Hauling
Onsite truck
Worker
Vendor
Hauling
Onsite truck
Worker
One -Way Trips per Day

20.0 0.00

17.5 113
108

16.0 0.00

15.0 0.77

21.6 0.00

7.50 Miles per Trip

18.5 10.2

20.0 18.5

10.2 20.0

18.5 10.2

20.0 18.5

10.2 20.0

18.5 10.2

20.0 18.5
Vehicle Mix
LDA,LDT1,LDT2

HHDT,MHDT
HHDT
HHDT
LDA,LDT1,LDT2

HHDT,MHDT
HHDT
HHDT
LDA,LDT1,LDT2
31U
38/51

Rancho Mirage Affordable Housing Family Apartments Detailed Report, 4/7/2025 Linear, Grubbing & Land Clearing Vendor
Linear, Grubbing & Land Clearing Hauling
Linear, Grubbing & Land Clearing Onsite truck
Linear, Grading & Excavation
Linear, Grading & Excavation Worker
Linear, Grading & Excavation Vendor
Linear, Grading & Excavation Hauling
Linear, Grading & Excavation Onsite truck

0.00 10.2

0.00 20.0

32.5 1.00

HHDT,MHDT
HHDT
HHDT

0.00 18.5

10.2 20.0
Linear, Drainage, Utilities, &
Sub -Grade
Linear, Drainage, Utilities, & Worker
Sub -Grade
Linear, Drainage, Utilities, & Vendor
Sub -Grade
Linear, Drainage, Utilities, & Hauling
Sub -Grade

27.5 0.00

0.00 LDA,LDT1,LDT2

HHDT,MHDT
HHDT
HHDT
Linear, Drainage, Utilities, & Onsite truck
Sub -Grade

18.5 10.2

20.0 Linear, Paving
Linear, Paving
Linear, Paving
Linear, Paving
Linear, Paving
Worker
Vendor
Hauling
Onsite truck

20.0 0.00

0.77 18.5

10.2 20.0
LDA,LDT1,LDT2

HHDT,MHDT
HHDT
HHDT

5.4. Vehicles

5.4.1. Construction Vehicle Control Strategies
Non -applicable. No control strategies activated by user.

5.5. Architectural Coatings
LDA,LDT1,LDT2

HHDT,MHDT
HHDT
HHDT
311
39/51

Rancho Mirage Affordable Housing Family Apartments Detailed Report, 4/7/2025 Phase Name
Residential Interior Area
Coated (sq ft)
Residential Exterior Area
Coated (sq ft)
Non -Residential Interior Area
Coated (sq ft)
Non -Residential Exterior Area
Coated (sq ft)
Parking Area Coated (sq ft)
Architectural Coating

5.6. Dust Mitigation

5.6.1. Construction Earthmoving Activities
15,975
5,325

0.00 0.00
5,227
Phase Name
Material Imported (cy)
Material Exported (cy)
Acres Graded (acres)
Material Demolished (sq. ft.)
Acres Paved (acres)
Linear, Grubbing & Land
Clearing

0.32 0.00
Linear, Grading & Excavation 0.00

0.00 Linear, Drainage, Utilities, &
Sub -Grade
Site Preparation
Grading
Paving

0.00 0.00

0.32 45,000

0.00 0.00

26.3 8.00

0.00 0.00

0.00 5.6.2. Construction Earthmoving Control Strategies Non -applicable. No control strategies activated by user.

5.7. Construction Paving

2.32 Land Use
Area Paved (acres)
% Asphalt
Apartments Mid Rise
Parking Lot
Road Construction

2.00 0.32
0%
100%
100%

5.8. Construction Electricity Consumption and Emissions Factors kWh per Year and Emission Factor (Ib/MWh)
Year
kWh per Year
CO2
CH4
N2O
0IL
40/51

Rancho Mirage Affordable Housing Family Apartments Detailed Report, 4/7/2025 2027
2028
2029
103

0.00 0.00
457
457
457

0.03 0.03

0.03 < 0.005
< 0.005
< 0.005

5.9. Operational Mobile Sources

5.9.1. Unmitigated
Land Use Type
Apartments Mid
Rise
Parking Lot
Trips/Weekday
722

0.00 Trips/Saturday
722

0.00 Trips/Sunday
722

0.00 Trips/Year
263,512

0.00 VMT/Weekday
10,146

0.00 VMT/Saturday
10,146

0.00 VMT/Sunday
10,146

0.00 VMT/Year
3,703,455

0.00 5.10. Operational Area Sources

5.10.1. Hearths

5.10.1.1. Unmitigated
Hearth Type
Apartments Mid Rise
Wood Fireplaces
Gas Fireplaces
Propane Fireplaces
Electric Fireplaces
No Fireplaces
Conventional Wood Stoves
Catalytic Wood Stoves
Non -Catalytic Wood Stoves
Pellet Wood Stoves
Unmitigated (number)
0 0
0 0
150
0 0
0 0
313
41 / 51

Rancho Mirage Affordable Housing Family Apartments Detailed Report, 4/7/2025

5.10.2. Architectural Coatings
Residential Interior Area Coated (sq
ft)
Residential Exterior Area Coated (sq
ft)
Non -Residential Interior Area Coated
(sq ft)
Non -Residential Exterior Area
Coated (sq ft)
Parking Area Coated (sq ft)
69413
46,854

0.00 5.10.3. Landscape Equipment

0.00 5,227
Season
Unit
Value
Snow Days
Summer Days
day/yr
day/yr

0.00 180

5.11. Operational Energy Consumption
5A1.1. Unmitigated
Electricity (kWh/yr) and CO2 and CH4 and N2O and Natural Gas (kBTU/yr) Land Use
Apartments Mid Rise
Electricity (kWh/yr)
848,874
CO2
457
CH4

0.0330
N2O

0.0040
Parking Lot
76,317
457

5.12. Operational Water and Wastewater Consumption

5.12.1. Unmitigated

0.0330

0.0040
Natural Gas (kBTU/yr)
1,933,922

0.00 Land Use
Indoor Water (gal/year)
Outdoor Water (gal/year)
Apartments Mid Rise
Parking Lot
6,101,066
981,696

0.00 0.00

5.13. Operational Waste Generation
314
42/51

Rancho Mirage Affordable Housing Family Apartments Detailed Report, 4/7/2025

5.13.1. Unmitigated
Land Use
Apartments Mid Rise
Parking Lot
Waste (ton/year)
111

0.00 Cogeneration (kWh/year)

5.14. Operational Refrigeration and Air Conditioning Equipment

5.14.1. Unmitigated
Land Use Type
Apartments Mid Rise
Apartments Mid Rise
Equipment Type
Refrigerant
GWP
Average room A/C &
Other residential A/C
and heat pumps
R -410A
2,088
Household
refrigerators and/or
freezers
R -134a
1,430
Quantity (kg)
Operations Leak Rate
< 0.005

2.50 0.12

0.60 Service Leak Rate

2.50 0.00
Times Serviced

10.0 1.00

5.15. Operational Off -Road Equipment

5.15.1. Unmitigated
Equipment Type
Fuel Type
Engine Tier
Number per Day
Hours Per Day
Horsepower
Load Factor

5.16. Stationary Sources

5.16.1. Emergency Generators and Fire Pumps
Equipment Type
Fuel Type
Number per Day
Hours per Day
Hours per Year
Horsepower
Load Factor

5.16.2. Process Boilers
Equipment Type
Fuel Type
Number
Boiler Rating (MMBtu/hr)
Daily Heat Input (MMBtu/day)
Annual Heat Input (MMBtu/yr)
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Rancho Mirage Affordable Housing Family Apartments Detailed Report, 4/7/2025

5.17. User Defined
Equipment Type
Fuel Type

5.18. Vegetation

5.18.1. Land Use Change

5.18.1.1. Unmitigated
Vegetation Land Use Type
Vegetation Soil Type
Initial Acres
Final Acres

5.18.1. Biomass Cover Type

5.18.1.1. Unmitigated
Biomass Cover Type
Initial Acres
Final Acres

5.18.2. Sequestration

5.18.2.1. Unmitigated
Tree Type
Number
Electricity Saved (kWh/year)
Natural Gas Saved (btu/year)

6. Climate Risk Detailed Report

6.1. Climate Risk Summary
Cal -Adapt midcentury 2040-2059 average projections for four hazards are reported below for your project location. These are under Representation Concentration Pathway (RCP) 8.5 which assumes GHG emissions will continue to rise strongly through 2050 and then plateau around 2100.

Climate Hazard
Result for Project Location
Unit
Temperature and Extreme Heat

23.4 annual days of extreme heat
Extreme Precipitation

0.00 316
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annual days with precipitation above 20 mm

Rancho Mirage Affordable Housing Family Apartments Detailed Report, 4/7/2025 Sea Level Rise
Wildfire 0.00
meters of inundation depth
annual hectares burned
Temperature and Extreme Heat data are for grid cell in which your project are located. The projection is based on the 98th historical percentile of daily maximum/minimum temperatures from observed historical data (32 climate model ensemble from Cal -Adapt, 2040-2059 average under RCP 8.5). Each grid cell is 6 kilometers (km) by 6 km, or 3.7 miles (mi) by 3.7 mi.

Extreme Precipitation data are for the grid cell in which your project are located. The threshold of 20 mm is equivalent to about % an inch of rain, which would be light to moderate rainfall if received over a full day or heavy rain if received over a period of 2 to 4 hours. Each grid cell is 6 kilometers (km) by 6 km, or 3.7 miles (mi) by 3.7 mi.

Sea Level Rise data are for the grid cell in which your project are located. The projections are from Radke et al. (2017), as reported in Cal -Adapt (Radke et al., 2017, CEC-500-2017-008), and consider inundation location and depth for the San Francisco Bay, the Sacramento -San Joaquin River Delta and California coast resulting different increments of sea level rise coupled with extreme storm events. Users may select from four scenarios to view the range in potential inundation depth for the grid cell. The four scenarios are: No rise, 0.5 meter, 1.0 meter, 1.41 meters Wildfire data are for the grid cell in which your project are located. The projections are from UC Davis, as reported in Cal -Adapt (2040-2059 average under RCP 8.5), and consider historical data of climate, vegetation, population density, and large (> 400 ha) fire history. Users may select from four model simulations to view the range in potential wildfire probabilities for the grid cell. The four simulations make different assumptions about expected rainfall and temperature are: Warmer/drier (HadGEM2-ES), Cooler/wetter (CNRM-CM5), Average conditions (CanESM2), Range of different rainfall and temperature possibilities (MIROC5). Each grid cell is 6 kilometers (km) by 6 km, or 3.7 miles (mi) by 3.7 mi.

6.2. Initial Climate Risk Scores
Climate Hazard
Exposure Score
Sensitivity Score
Adaptive Capacity Score
Vulnerability Score
Temperature and Extreme Heat
Extreme Precipitation
Sea Level Rise
Wildfire
Flooding
Drought
Snowpack Reduction
Air Quality Degradation
1 N/A
N/A
N/A
N/A
0 N/A
N/A
0 N/A
N/A
N/A
N/A
0 N/A
0 N/A
N/A
N/A
N/A
0 N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A

N/A N/A
The sensitivity score reflects the extent to which a project would be adversely affected by exposure to a climate hazard. Exposure is rated on a scale of 1 to 5, with a score of 5 representing the greatest exposure.

The adaptive capacity of a project refers to its ability to manage and reduce vulnerabilities from projected climate hazards. Adaptive capacity is rated on a scale of 1 to 5, with a score of 5 representing the greatest ability to adapt.

The overall vulnerability scores are calculated based on the potential impacts and adaptive capacity assessments for each hazard. Scores do not include implementation of climate risk reduction measures.

6.3. Adjusted Climate Risk Scores
Climate Hazard
Exposure Score
Sensitivity Score
Adaptive Capacity Score
Vulnerability Score
Temperature and Extreme Heat 1
1 317
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1 2

Rancho Mirage Affordable Housing Family Apartments Detailed Report, 4/7/2025 Extreme Precipitation
N/A
N/A
N/A
N/A
Sea Level Rise
N/A
N/A
N/A
N/A
Wildfire
N/A
N/A
N/A
N/A
Flooding
N/A
N/A

N/A N/A
Drought
1 1
1 2
Snowpack Reduction
N/A
N/A
N/A
N/A
Air Quality Degradation
N/A
N/A
N/A
N/A
The sensitivity score reflects the extent to which a project would be adversely affected by exposure to a climate hazard. Exposure is rated on a scale of 1 to 5, with a score of 5 representing the greatest exposure.

The overall vulnerability scores are calculated based on the potential impacts and adaptive capacity assessments for each hazard. Scores include implementation of climate risk reduction measures.

6.4. Climate Risk Reduction Measures

7. Health and Equity Details

7.1. CalEnviroScreen 4.0 Scores
The maximum CalEnviroScreen score is 100. A high score (i.e., greater than 50) reflects a higher pollution burden compared to other census tracts in the state.

Indicator
Result for Project Census Tract
Exposure Indicators
AQ-Ozone

88.7 AQ-PM

7.34 AQ-DPM

43.4 Drinking Water

45.4 Lead Risk Housing

1.31 Pesticides

0.00 Toxic Releases

3.08 Traffic

64.6 Effect Indicators
3 1-8
6/5

Rancho Mirage Affordable Housing Family Apartments Detailed Report, 4/7/2025 CleanUp Sites

0.00 Groundwater

0.00 Haz Waste Facilities/Generators

43.3 Impaired Water Bodies

0.00 Solid Waste

0.00 Sensitive Population
—
Asthma

20.9 Cardio-vascular

16.5 Low Birth Weights

20.3 Socioeconomic Factor Indicators
—
Education

25.9 Housing

86.8 Linguistic

7.38 Poverty

21.5 Unemployment

4.23 7.2. Healthy Places Index Scores
The maximum Health Places Index score is 100. A high score (i.e., greater than 50) reflects healthier community conditions compared to other census tracts in the state.

Indicator
Result for Project Census Tract
Economic
Above Poverty
Employed
Median HI
Education
Bachelor's or higher
High school enrollment
Preschool enrollment
Transportation

47.56833055

15.56525087

74.56691903

65.96945977
100

48.45374054
319
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Rancho Mirage Affordable Housing Family Apartments Detailed Report, 4/7/2025 Auto Access
Active commuting
Social
2 -parent households
Voting
Neighborhood
Alcohol availability
Park access
Retail density
Supermarket access
Tree canopy
Housing
Homeownership
Housing habitability
Low-inc homeowner severe housing cost burden
Low-inc renter severe housing cost burden
Uncrowded housing
Health Outcomes
Insured adults
Arthritis
Asthma ER Admissions
High Blood Pressure
Cancer (excluding skin)
Asthma
Coronary Heart Disease
Chronic Obstructive Pulmonary Disease
Diagnosed Diabetes
Life Expectancy at Birth

37.4566919

25.81804183

97.56191454

86.88566662

82.80508148

2.194276915

35.17259079

45.92583087

17.8108559

83.62633132

22.35339407

25.38175286

6.274862056

70.21686129

97.45925831

0.0 80.6

0.0 0.0

0.0 0.0
320
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Rancho Mirage Affordable Housing Family Apartments Detailed Report, 4/7/2025 Cognitively Disabled
Physically Disabled
Heart Attack ER Admissions
Mental Health Not Good
Chronic Kidney Disease
Obesity
Pedestrian Injuries
Physical Health Not Good
Stroke
Health Risk Behaviors
Binge Drinking
Current Smoker
No Leisure Time for Physical Activity
Climate Change Exposures
Wildfire Risk
SLR Inundation Area
Children
Elderly
English Speaking
Foreign -born
Outdoor Workers
Climate Change Adaptive Capacity
Impervious Surface Cover
Traffic Density
Traffic Access
Other Indices
Hardship
Other Decision Support

39.7 49.3

64.0 0.0

0.0 0.0

19.6 0.0

0.0 0.0

79.8 0.9

70.5 10.7

98.2 47.2

47.5 23.0

34.9 321
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Rancho Mirage Affordable Housing Family Apartments Detailed Report, 4/7/2025 2016 Voting

92.5 7.3. Overall Health & Equity Scores
Metric
CalEnviroScreen 4.0 Score for Project Location (a)
Healthy Places Index Score for Project Location (b)
Project Located in a Designated Disadvantaged Community (Senate Bill 535) Project Located in a Low -Income Community (Assembly Bill 1550) Project Located in a Community Air Protection Program Community (Assembly Bill 617) Result for Project Census Tract

7.00 56.0
No
No
No
a: The maximum CalEnviroScreen score is 100. A high score (i.e., greater than 50) reflects a higher pollution burden compared to other census tracts in the state. b: The maximum Health Places Index score is 100. A high score (i.e., greater than 50) reflects healthier community conditions compared to other census tracts in the state.

7.4. Health & Equity Measures
No Health & Equity Measures selected.

7.5. Evaluation Scorecard
Health & Equity Evaluation Scorecard not completed.

7.6. Health & Equity Custom Measures
No Health & Equity Custom Measures created.

8. User Changes to Default Data
Screen
Land Use
Justification
The residential development is proposed on 5 -acres or 217,800 square feet of vacant land to include seven permanent three-story tall residential buildings, outdoor amenity space including a Community Center and swimming pool, and on -site parking. These on -site improvements are represented under "Residential" and "Parking" land uses. Given CaIEEMod does not have a separate recreational land use for a community center, the facilities's 3,353 square feet are added to the total building area under "Residential". Similarly, the swimming pool square footage (948 sf) is added to the total building area for "Residential" because CaIEEMod's recreational swimming pool land use only represents buildings associated with the land use, such as restrooms/changing rooms. The total lot acreage is modified to account for these 322d d on -site usage (i.e., Community Center and swimming pool). Off -site development of Via 50/51

Rancho Mirage Affordable Housing Family Apartments Detailed Report, 4/7/2025 Vail adjacent to the property's eastern frontage is proposed and reflect under "Linear" land use.

Construction: Construction Phases
The project is estimated to begin construction in February 2027 and be operation by 2029.

Operations: Vehicle Data
The Project -specific traffic report projects the residential development will generate 772 daily vehicle trips.

To calculate weekday trips rate, daily vehicle trips were divided by "Apartment Mid Rise" size to generate a rate of 4.813 size per day.

Construction: Off -Road Equipment
"Other Construction Equipment" accounts for water trucks irrigating the site for dust control measures, pursuant to SCAQMD Rule 403.

Adjusted CaIEEMod construction equipment duration assuming that primary equipment operate an average of 7 hrs/day, material -handling equipment operate an avg. of 5 hrs/day, and other construction equipment operate an avg. of 3 hrs/day.

Construction: Dust From Material Movement
Development of the residential parcel would result in the export of 45,000 CY of material.

Grading and excavation of Via Vail would result in a balanced site, meaning the amount of material imported and exported is the same.

Construction: Trips and VMT
The Project's total paved area is 2 acres for parking and 0.32 acres for Via Vail.

The total paved area is then converted from ac to sf and multiplied by the average depth of pavement (0.25 ft).

The value is converted to cubic yards and divided by CaIEEMod default value of hauling trips (16 cubic yards per hauling trip).

The total paving duration for parking and Via Vail is 75 days, which divides the total number of hauling trips, resulting in the Project generating 0.773 hauling trips per day during the two paving phases.

Operations: Hearths
None of the residential units would include a fireplace or wood stove.

Operations: Architectural Coatings
Added residential interior to reflect the total building area. 323
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Rancho Mirage Affordable Housing Family Apartments
Initial Study/Mitigated Negative Declaration
May 2025
Appendix B
Biological Resources Assessment
City of Rancho Mirage B
324

VIA VAIL 3 PROJECT
Biological Resources Assessment & Coachella Valley
Multiple Species Habitat Conservation Plan Compliance Report

RIVERSIDE COUNTY, CALIFORNIA
Prepared for:

Terra Nova Planning and Research
42635 Melanie Place, Suite 101
Palm Desert, CA 92211
Nicole Criste, Principal
Phone: (760) 568-9918
Prepared by:

WSP USA Environment & Infrastructure Inc.
862 E Hospitality Ln #350
San Bernardino, CA 92408
(909) 888-1106
WSP Job # US -El -P585_1.9734
Principal Field Investigator:

Dale Hameister
Report Author:

Dale Hameister
Survey: May 2024
325

Via Vail 3 Apartment Homes Project
Biological Resources Assessment
May 2024

TABLE OF CONTENTS

1.0 INTRODUCTION 1

2.0 PROJECT LOCATION / DESCRIPTION 1

3.0 REGULATORY FRAMEWORK 1

3.1 Federal 1

3.2 State 2

3.3 Coachella Valley Multiple Species Habitat Conservation Plan 4

4.0 METHODS 5

4.1 Literature Review 5

4.2 Field Assessment 5

5.0 RESULTS 5

5.1 Coachella Valley Multiple Species Habitat Conservation Plan 5

5.2 Weather Conditions 6

5.3 Topography and Soils 6

5.4 Vegetation 6

5.5 Wildlife 6

5.6 Special Status Biological Resources 6

5.7 Discussion of the Special -status Species Tables 15

5.7.1 CVMSHCP Covered Species 15

5.7.2 Potentially Occurring Species Not Covered Under the CVMSHCP and USFWS IPAC Species 15

6.0 DISCUSSION 16

6.1 Protection of Nesting Birds 16

6.2 Burrowing Owl 16

7.0 CONCLUSION 16

8.0 LITERATURE CITED AND REFERENCES 17
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LIST OF TABLES
Table 1. Special Status Plants 7
Table 2. Special Status Vegetation Communities 8
Table 3-5. Special Status Wildlife 9

LIST OF APPENDICES
Appendix A. Figures
Figure 1. Project Location
Figure 2. USGS Topo
Figure 3. Site Vicinity
Figure 4. Soils
Figure 5. Vegetation
Figure 6. CVMSHCP
Appendix B. Plants and Vertebrate Wildlife Observed
Appendix C. Site Photos
Appendix D. Coachella Valley Native Plants Recommended for Landscaping Appendix E. Prohibited Invasive Ornamental Plants
Appendix F. USFWS IPaC Report
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Biological Resources Assessment
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1.0 INTRODUCTION
At the request of Terra Nova Planning and Research (Client), this biological resource assessment report (BRAR) was prepared by WSP USA Environment & Infrastructure Inc. (WSP) for the proposed Via Vail 3 Apartment Homes Project (project site/project), located in the city of Rancho Mirage, Riverside County., California. Information contained herein is intended to be used for compliance with the Coachella Valley Multiple Species Habitat Conservation Plan (CVMSHCP), California Environmental Quality Act (CEQA), as well as federal and California Endangered Species Acts.

2.0 PROJECT LOCATION / DESCRIPTION
The purpose of the proposed project is to development of apartment homes. To document the current biological resources within the project, a general biological resources assessment is required. This will provide a detailed assessment of the existing conditions. The project is located in Parcel 3, generally located north of B Street, southwest of Via Vail and east of Key Largo Avenue, in the city of Rancho Mirage, Riverside County. (Appendix A — Figure 1). Specifically, the project site is located within Section 30; Township 4 South; Range 6 East as shown on the United States Geological Survey (USGS) Cathedral City, California, 7.5 -minute topographic quadrangle (Appendix A — Figure 2). The geographic coordinates near the approximate center of the project area are 33.795865° north latitude and -116.392824° west longitude. The elevation of the project site ranges from approximately 296 to 312 feet above mean sea level.

3.0 REGULATORY FRAMEWORK

3.1 Federal
Endangered Species Act (ESA) — The United States Fish and Wildlife Service (USFWS) and the National Marine Fisheries Service are the designated federal agencies accountable for administering the ESA. The ESA defines species as "endangered" or "threatened" and provides regulatory protection at the federal level.
• Section 9 of the ESA prohibits the "take" of listed (i.e., endangered or threatened) species.

The ESA's definition of take is "to harass, harm, pursue, hunt, shoot, wound, kill, trap, capture, collect, or attempt to engage in such conduct." Recognizing that take cannot always be avoided, Section 10(a) includes provisions for take that is incidental to, but not the purpose of, otherwise lawful activities. Specifically, Section 10(a) (1) (A) permits (authorized take permits) are issued for scientific purposes. Section 10(a) (1) (B) permits (incidental take permits) are issued for the incidental take of listed species that does not jeopardize the species.
• Section 7 (a) (2) requires federal agencies to evaluate the proposed project with respect to listed or proposed listed, species and their respective critical habitat (if applicable). Federal agencies must employ programs for the conservation of listed species and are prohibited from authorizing, funding, or carrying out any action that would jeopardize a listed species or destroy or modify its "critical habitat."
As defined by the ESA, "individuals, organizations, states, local governments, and other non- federal entities are affected by the designation of critical habitat only if their actions occur on federal lands, require a federal permit, license, or other authorization, or involve federal funding.

Section 10(a) of the ESA authorizes the issuance of incidental take permits and establishes standards for the content of habitat conservation plans (see Section 3.3 below).

Migratory Bird Treaty Act (MBTA) — Treaties signed by the U.S., Great Britain, Mexico, Japan, and the countries of the former Soviet Union make it unlawful to pursue, capture, kill, and/or 328

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Biological Resources Assessment
May 2024
possess, or attempt to engage in any such conduct to any migratory bird, nest, egg or parts thereof listed in the document. As with the ESA, the MBTA also allows the Secretary of the Interior to grant permits for the incidental take of these protected migratory bird species.

National Environmental Policy Act (NEPA) — If portions of a proposed project could fall under the jurisdiction of a federal agency (i.e., U.S. Bureau of Reclamation, U.S. Army Corps of Engineers) they are subject to environmental review pursuant to NEPA. NEPA establishes certain criteria that must be adhered to for any project that is "financed, assisted, conducted or approved" by a federal agency. The federal lead agency is required to "determine whether the proposed action will significantly affect the quality of the human environment." Section 404 of the Clean Water Act — This section of the Clean Water Act, administered by the U.S. Army Corps of Engineers (USACE), regulates the discharge of dredged and fill material into "waters of the United States." The USACE has created a series of nationwide permits that authorize certain activities within waters of the U.S. provided that the proposed activity does not exceed the impact threshold of 0.5 acre for nationwide permits, takes steps to avoid impacts to wetlands and other designated U.S. waters where practicable, minimizes potential impacts to wetlands, and provides compensation for any remaining, unavoidable impacts through activities to restore or create wetlands. For projects that exceed the threshold for nationwide permits, individual permits under Section 404 can be issued. An inspection of the project site to determine presence or absence of potential jurisdictional wetlands and waters was conducted during the assessment for this project.

3.2 State
California Endangered Species Act (CESA) — This legislation is similar to the federal ESA, but it is administered by the California Department of Fish and Wildlife (CDFW — formerly Department of Fish and Game). The CDFW is authorized to enter into "memoranda of understanding" with individuals, public agencies, and other institutions to import, export, take, or possess state -listed species for scientific, educational, or management purposes. CESA prohibits the take of state - listed species except as otherwise provided in state law. Unlike the federal ESA, the CESA applies the take prohibitions to species currently petitioned for state -listing status (candidate species).

State lead agencies are required to consult with CDFW to ensure that actions are not likely to jeopardize the continued existence of any state -listed species or result in the destruction or degradation of occupied habitat.

California Environmental Quality Act (CEQA) — The basic goal of CEQA is to maintain a high - quality environment now and in the future. The specific goals are for California's public agencies to:
1) identify the significant environmental effects of their actions; and, either 2) avoid those significant environmental effects, where feasible; or 3) mitigate those significant environmental effects, where feasible.

CEQA applies to "projects" proposed to be undertaken or requiring approval by state and local government agencies. Projects are activities that have the potential to have a physical impact on the environment and may include the enactment of zoning ordinances, the issuance of conditional use permits and the approval of tentative subdivision maps. Where a project requires approvals from more than one public agency, CEQA requires one of these public agencies to serve as the "lead agency."
A "lead agency" must complete the environmental review process required by CEQA. The most basic steps of the environmental review process are to:
4) Determine if the activity is a "project" subject to CEQA. 329

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5) Determine if the "project" is exempt from CEQA.
6) Perform an Initial Study to identify the environmental impacts of the project and determine whether the identified impacts are "significant". Based on its findings of "significance", the lead agency prepares one of the following environmental review documents:
a) Negative Declaration if it finds no "significant" impacts. b) Mitigated Negative Declaration if it finds "significant" impacts but revises the project to avoid or mitigate those significant impacts.
c) Environmental Impact Report (EIR) if it finds "significant" impacts.

While there is no ironclad definition of "significance", Article 5 of the State CEQA Guidelines (California Natural Resources Agency 2014) provides criteria to lead agencies in determining whether a project may have significant effects.

The Native Plant Protection Act (NPPA) — The NPPA includes measures to preserve, protect, and enhance rare and endangered native plant species. Definitions for "rare and endangered" are different from those contained in CESA. However, the list of species afforded protection in accordance with the NPPA includes those listed as rare and endangered under CESA. NPPA provides limitations on take as follows: "no person will import into this state, or take, possess, or sell within this state" any rare or endangered native plants, except in accordance with the provisions outlined in the act. If a landowner is notified by CDFW, pursuant to section 1903.5 that a rare or endangered plant is growing on their property, the landowner shall notify CDFW at least 10 days prior to the changing of land uses to allow CDFW to salvage the plants.

Natural Community Conservation Planning (NCCP) Program — A NCCP, which is managed by the CDFW, is intended to conserve multiple species and their associated habitats, while also providing for compatible use of private lands. Through local planning, the NCCP planning process is designed to provide protection for wildlife and natural habitats before the environment becomes so fragmented or degraded by development that species listing are required under CESA. Instead of conserving small, often isolated "islands" of habitat for just one listed species, agencies, local jurisdictions, and/or other interested parties have an opportunity through the NCCP to work cooperatively to develop plans that consider broad areas of land for conservation that would provide habitat for many species. Partners enroll in the programs, and by mutual consent, areas considered to have high conservation priorities or values are set aside and protected from development. Partners may also agree to study, monitor, and develop management plans for these high value "reserve" areas. The NCCP provides an avenue for fostering economic growth by allowing approved development in areas with lower conservation value. The project site is in a combined Habitat Conservation Plan (HCP) / NCCP, see Section 3.3.

Sections 1600-1603 of the State Fish and Game Code — The California Fish and Game (Wildlife) Code, pursuant to Sections 1600 through 1603, regulates all diversions, obstructions, or changes to the natural flow or bed, channel, or bank of any river, stream, or lake that supports fish or wildlife resources. Under state code, CDFW jurisdiction is assessed in the field based on one, or a combination, of the following criteria:
7) At minimum, intermittent, and seasonal flow through a bed or channel with banks and that also supports fish or other aquatic life.
8) A watercourse having a surface or subsurface flow regime that supports or that has supported riparian vegetation.
9) Hydrogeomorphically distinct top -of -embankment to top -of -embankment limits. 10) Outer ground cover and canopy extents of, typically, riparian associated vegetation species that would be sustained by surface and/or subsurface waters of the watercourse. 330

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The CDFW requires that public and private interests apply for a "Streambed Alteration Agreement" for any project that may impact a streambed or wetland. The CDFW has maintained a "no net loss" policy regarding impacts to streams and waterways and requires replacement of lost habitats on at least a 1:1 ratio.

Section 2081 of the State Fish and Game Code — Under Section 2081 of the California Fish and Game Code, the CDFW authorizes individuals or public agencies to import, export, take, or possess state endangered, threatened, or candidate species in California through permits or memoranda of understanding. These acts, which are otherwise prohibited, may be authorized through permits or "memoranda of understanding" if (1) the take is incidental to otherwise lawful activities, (2) impacts of the take are minimized and fully mitigated, (3) the permit is consistent with regulations adopted in accordance with any recovery plan for the species in question, and (4) the applicant ensures suitable funding to implement the measures required by the CDFW. The CDFW shall make this determination based on the best scientific information reasonably available and shall include consideration of the species' capability to survive and reproduce.

Section 3505.5 of the State Fish and Game Code — This section makes it unlawful to take, possess, or destroy any birds in the order Falconiformes or Strigiformes (birds -of -prey, e.g.: owls, hawks, eagles, etc.) or to take, possess, or destroy the nest or eggs of any bird -of -prey.

Clean Water Act— The Regional Water Quality Control Board (RWQCB) regulates activities pursuant to Section 401(a)(1) of the Clean Water Act (CWA). Section 401 of the CWA specifies that certification from the State is required for any applicant requesting a federal license or permit to conduct any activity including, but not limited to, the construction or operation of facilities that may result in any discharge into navigable waters. Through the Porter Cologne Water Quality Control Act, the RWQCB asserts jurisdiction over Waters of the State of California (WSC) which is generally the same as WUS but may also include isolated waterbodies. The Porter Cologne Act defines WSC as "surface water or ground water, including saline waters, within the boundaries of the state".

3.3 Coachella Valley Multiple Species Habitat Conservation Plan Finalized in October 2008, and amended in 2016, the CVMSHCP is a comprehensive regional plan that addresses the conservation needs of 27 species of native flora and fauna and 24 natural vegetation communities occurring throughout the Coachella Valley region of western Riverside County, California. Permits for the CVMSHCP were issued by the CDFW on September 9, 2008 and the United States Fish and Wildlife Service (USFWS) on October 1, 2008 (TE104604-0).

Managed by the Coachella Valley Conservation Commission (CVCC), CVMSHCP participants include Riverside County, the Cities of Cathedral City, Coachella, Desert Hot Springs, Indian Wells, Indio, La Quinta, Palm Desert, Palm Springs, Rancho Mirage, as well as the Coachella Valley Association of Governments (CVAG), Coachella Valley Water District, Imperial Irrigation District, Mission Springs Water District and the California Department of Transportation (CVAG 2008, 2016).

The CVMSHCP serves two primary purposes: Balancing environmental protection and economic development objectives in the CVMSHCP planning area and simplifying compliance with endangered species related laws. The CVMSHCP accomplishes this by conserving unfragmented habitat to permanently protect and secure viable populations of the covered 27 species within the planning area. The covered species include those plants and animals that are either currently listed as threatened or endangered, are proposed for listing, or are believed by an appointed Scientific Advisory Committee, USFWS and CDFW, to have a high probability of being proposed for listing in the future if not conserved by the CVMSHCP. The goal of the CVMSHCP is to meet the requirements of the ESA and CESA, while at the same time allowing for the economic growth (land development) within the plan area without significant delay or hidden 331

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May 2024
costs. Under the CVMSHCP, land development/mitigation fees are collected from all new development projects occurring in the plan area. The purpose of this fee is to support the assembly of a preserve system for the covered species and natural vegetation communities within areas identified as having high conservation value (CVAG 2008).

4.0 METHODS

4.1 Literature Review
In preparation for the field surveys, a literature search was conducted to identify special status biological resources known from the vicinity of the project site. In the context of this report, and for the purpose of this assessment, vicinity is defined as areas within a 5 -mile radius of the project site.

The literature search included a review of the following documents:
• California Natural Diversity Data Base (CNDDB) RareFind 5 (CDFW 2024a) • Special Animals List (CDFW 2024b)
• California Native Plant Society's (CNPS) Inventory of Rare, Threatened, and Endangered Plants of California (CNPS 2023a)
• CVMSHCP (CVAG 2008)
• United States Department of Agriculture (USDA), Natural Resources Conservation Service (NRCS). 2024. Web Soil Survey
• USGS 7.5' Cathedral City. quadrangle (USGS 2021)
Scientific nomenclature for this document follows standard reference sources: For plant communities, CVMSHCP (CVAG 2008), Sawyer et. al (2009), and/or Holland (1986); for flora, Jepson eFlora (2022) and the USDA NRCS PLANTS Database (2022); for amphibians, reptiles, and mammals, CDFW (2016); and for birds, California Bird Records Committee (2022).

4.2 Field Assessment
The field assessment was conducted on 18 April 2024 by WSP Senior Wildlife Biologist Dale Hameister. On -site suitable habitat was assessed based on the presence of constituent habitat elements (e.g., soils, vegetation, and topography) characteristic of the potentially occurring special status biological resources determined by the literature review. The entire site and adjacent properties were also assessed for burrowing owl (Athene cunicularia). Inaccessible areas were scanned for burrowing owl habitat and sign (i.e., burrows & perches with whitewash) with binoculars. All on -site flora and fauna observed or otherwise detected (e.g., vocalizations, presence of scat, tracks, and/or bones) during the assessment were recorded in field notes and are included in Appendix B. General weather and site conditions were also recorded at the beginning and end of the survey. Temperatures and wind speeds were recorded with a handheld Kestrel 2000 anemometer. Percent cloud cover was visually estimated.

5.0 RESULTS
The project site contains sandy soils the entire site comprises of highly disturbed creosote scrub.

There is an active dog park to the west and a commercial development to the north of the project site. There is a small amount of undeveloped land to the south and east with residential development beyond. MPeople were observed using the project site to walk their dogs and let them run off leash. Representative site photos are included in Appendix C.

5.1 Coachella Valley Multiple Species Habitat Conservation Plan The project site is located within the CVMSHCP fee area and the but is not located within or adjacent to any Conservation Areas (Figure 4, Appendix A). The development of the project site 332

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will have no effect on any CVMSHCP Conservation Areas. The project site is 2.2 miles southeast of the Thousand Palms Conservation Area.

5.2 Weather Conditions
Weather conditions during the field assessment were clear and warm. There was 40% cloud cover with temperatures that ranged from 78 to 84 degrees Fahrenheit. Winds were calm with wind speeds measured between 0 to 2 miles per hour.

5.3 Topography and Soils
The project site is very sandy and relatively flat with small undulating hills. One soil type, Myoma fine sand has been mapped on the project site. (USDA, NRCS. 2024) (Appendix A - Figure 3).

Typically, Myoma soils are light olive gray, moderately alkaline fine and very fine sands to a depth of about 31 inches. Below 31 inches they are strongly alkaline very fine sands.

The site does not contain active sand dunes or clay lenses.

5.4 Vegetation
The project site consists of sparse and disturbed creosote scrub. The entire property shows signs of disturbance including tire tracks, dog prints and scat, trash, and human footprints. Shrubs observed include creosote bush (Larrea tridentata), four -wing saltbush (Atriplex canescens), and dyebush (Psorothamnus emoryi). Annual species observed include desert dicoria (Dicoria canescens), Spanish needles (Palafoxia arida), narrow leaved forget me not (Johnstonella angustifolia), fanleaf crinklemat (Tiquilia plicata), Sahara mustard (Brassica tournefortii), old han schismus (Schismus barbatus).

5.5 Wildlife
Vertebrate wildlife directly observed and/or detected otherwise (e.g., scat, bones, tracks, feathers, burrows, etc.) were typical to species common to the region (Appendix B). This included some species common to desert scrub and/or developed areas of Coachella Valley. Wildlife observed onsite includes American crow (Corvus brachyrhynchos), house finch (Haemorhous mexicanus), verdin (Auriparus flaviceps), and Say's phoebe (Sayornis saya).

The number of species detected does not represent the total number of species that may occur on the project site. Brief, one visit assessments are limited by the seasonal timing and short duration of the survey period as well as the nocturnal, fossorial and/or migratory habits of many animals. It had rained the night before the survey, so the sandy surface was wet. There was not much evidence of rodent burrows as the sandy nature of the site would not provide a good burrowing substrate. No actively nesting birds were detected on or adjacent to the site during the assessment.

5.6 Special Status Biological Resources
Some plant and/or animal taxa are designated as having special status due to declining populations, limited geographic distributions and/or vulnerability to climate change, habitat loss and/or fragmentation. Some have been listed as threatened or endangered by the USFWS or by the CDFW and are protected by the federal and state ESAs. Others have been identified, and are managed as sensitive by the USFWS, CDFW, or by private conservation organizations, including the CNPS, but have not been formally listed as threatened or endangered. Impacts to such species can still be considered significant under the CEQA, if not avoided, minimized and/or mitigated by specific project design and implementation.

The literature review and field visit resulted in a list of 36 special status biological resources which occur or potentially occur on the project site and/or vicinity (5 -mile radius) of the project site. 333

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Tables 1-5 provide a summary of these resources, their current conservation status, habitat associations and potential to occur on the project site. No species listed as threatened or endangered were observed on the site.

Table 1. Special Status Plant Species
Species
Protective Status
Habitat
Flowering
Period
Occurrence
Probability
Abronia villosa var. aurita
chaparral sand -verbena
F: None
C: None
CNPS: List 16.1
State Rank: S2
MSHCP: No
Sandy areas in chaparral
and coastal sage scrub,
dunes; 75-1600 m (246-
5249 ft) above mean sea
level (AMSL).

January
August
Absent
Chaparral and sage
scrub habitats lacking.

Records within the
region may be
erroneous,
misidentifications of
common subspecies.

The common subs
species is present.

Taxonomy of species is
questionable [A.

Sanders oers. com.

Astragalus lentiginosus
var. coachellae
Coachella Valley
milkvetch
F: END
C: None
CNPS List: 1B.2
State Rank: S1
MSHCP: Yes
Sandy flats, washes,
alluvial fans, sand field,
dunes and dune edges;
windblown sand deposits
40-655 m (131-2182 ft.)
AMSL, a CA endemic.

February -
May
Low
Aeolian [wind -
deposited] sand habitat
is present, but highly
disturbed and isolated.

Records in the vicinity
include one from the
1990s and the
remaining from 1975.

Not observed during
the survey.

Astragalus tricarinatus
triple -ribbed milkvetch
F: END
C: None
CNPS List: 1 B.2
State Rank: S2
MSHCP: Yes _
Sandy or gravelly areas in
Joshua tree woodland &
Sonoran desert scrub,
450-1,190 m (1,476-3,904
ft.) AMSL.

February
May
Absent
Habitat potentially
suitable but site is
below elevation for this
species.

Chorizanthe xanti var.
leucotheca
white-bracted
spineflower
F: None
C: None
CNPS List: 1 B.2
State Rank: S3
MSHCP: No
Sandy or gravelly areas in
Mojave desert scrub,
pinyon juniper woodland,
and coastal scrub; 300-
1200 m (984-4003 ft.)
AMSL.

April June
Absent
Habitat lacking
Euphorbia misera
cliff spurge
F: None
C: None
CNPS List: 2B.2
State Rank: S2
MSHCP: No
Rocky coastal bluff,
coastal scrub, Mojave
scrub; 10-500 m (33-1640
ft) AMSL.

December -
October
Absent
Rocky coastal bluff and
Mojave Desert scrub
habitat [cliffs] lacking
on -site, known from
adjacent steep cliffs of
Whitewater Cyn. This
population has declined
over the years and may
now be extirpated.

Only a single individual
found during most
recent survey [CNPS
2018, CCH 2018, A.

Sanders Ders. com.]
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California satintail
F: None
C: None
CNPS List: 2B.1
State Rank: S3
MSHCP: No
Coastal scrub, chaparral,
riparian scrub, Mojave
scrub, meadows and
seeps; 0-1215 m (0-3986
ft.) AMSL.

May
Absent
No suitable moist
habitat onsite
Nemacaulis denudata var.
gracilis
slender cottonheads
F: None
C: None
CNPS: List 2B.2
State Rank: S2
MSHCP: No
Coastal and desert
dunes, in Sonoran Desert
scrub (sandy); -50 to 400
m (164-1312 ft.) AMSL.

April — May
(rarely March)
Low
Habitat marginal, sandy
soils are present, 1948
CNDDB record is -4
mi. W of the site, along
Hwy. 111
Penstemon
pseudospectabilis ssp.
pseudospectabilis
desert beardtongue
F: None
C: None
CNPS List: 2B.2
State Rank: S3
MSHCP: No
Sandy or rocky washes in
Mojave Desert scrub and
Sonoran desert scrub; 80-
1953 m (262 - 6407 ft.)
AMSL.

January - May
Absent
No suitable habitat
Petalonyx linearis
narrow -leaf sandpaper-
plant
F: None
C: None
CNPS List: 2B.3
State Rank: S3?
MSHCP: No
Sandy or rocky canyons
in Mojave and Sonoran
desert scrubs
(Jan-Feb)Mar-
May(Jun-Dec)
Absent
Closest CNDDB record
is —5 mi. NE. of site
and is from 1879.

Saltugilia latimeri
Latimer's woodland-
gilia
F: None
C: None
CNPS: List 1 B.2
Global Rank: G3
State Rank: S3
MSHCP: No
Rocky, sandy, often
granitic, sometimes
washes in chaparral,
Mojave desert scrub,
pinyon and juniper
woodland; 400-1900 m
(1312-6234 ft) AMSL.

March -June
Absent
(Suitable habitat
lacking, site below
known elevational
range of species)
Selaginella eremophila
desert spike -moss
F: None
C: None
CNPS: List 2B.2
State Rank: S2S3
MSHCP: No
Shaded areas in crevices
among rocks or on
gravelly soils in Sonoran
desert scrub; 200-900 m
(656-2953 ft.) AMSL.

June
Absent
(Site is fully exposed to
sun, shaded areas very
limited)
Table 2. Special Status Vegetation Communities
Community
Protective Status
(F=Federal, C=California)
Occurrence
Probability
Desert Fan Palm Oasis
Woodland
F: ND
C: ND
State rank: S3.2
CVMSHCP: No
Absent
This habitat is not present on project site.

Southern Riparian Forest
F: ND
C: ND
State rank: S4
CVMSHCP: No
Absent
This habitat is not present on project site.
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Table 3. Special Status Invertebrates
Species
Protective Status
(F=Federal, C=California)
Habitat
Occurrence
Probability
Bombus crotchii
Crotch's bumble bee
F: C
C: C END
State Rank: S2
CVMSHCP: No
Mainly coastal California east
to the Sierra -Cascade Crest
and south into Baja.

Absent
Most records are
from cismontane
(coastal and inland
valley) California.

Not expected on this
site unless there
were sufficient
flowering plants
favored by this
species.

Dinacoma caseyi
Casey's June beetle
F: END
C: None
State rank: S1
MSHCP: No
Known from only two main
populations in the southern
Palm Springs area,
generally associated with Palm
Canyon Wash and its
associated floodplain. Needs
soils that are not too rocky or
compacted and difficult to
burrow in.

Absent
The site is 4.8 miles
E of the currently
known range of the
species. Site is not
located within the
historic range of the
species.

Danaus plexippus
Monarch Butterfly
F: C
C: CSC
State Rank: S2S3
CVMSHCP: No
Can be found in a variety of
areas where milkweed and
flowering plants are present;
milkweeds are necessary for
breeding
Absent
No milkweed present
on -site. Very little
remaining vegetation
for nectar sources.

Macrobaenetes valgum
Coachella ggiant sand treader
cricket
F: None
C: None
State rank: S1S2
MSHCP: Yes
Wind -deposited sand dune
ridges, winter rains somewhat
regulate abundance
Low
Habitat at site is
marginal, very
limited loose wind -
deposited sand
areas. Area is highly
disturbed.

Stenopelmatus cahuilaensis
Coachella Valley Jerusalem
cricket
F: None
C: None
State rank: S1 S2
MSHCP: Yes
Sand dune and sand field
habitats, in the vicinity of the
north base of the San Jacinto
Mountains
Low
Habitat at site is
marginal, very
limited loose wind -
deposited sand
areas. Area is highly
disturbed.

Table 3. Special Status Amphibians & Reptiles
Species
Protective Status
(F=Federal, C=California)
Habitat
Occurrence
Probability
Anniella stebbinsi
southern California legless
lizard
F = None
C = SSC
NDDB Element Rank:

Global = G3
State = S3
MSHCP = No
Occurs in a variety of habitats,
but seems to prefer areas with
loose, moist soils (high
moisture content).

Low
Some potential
habitat onsite,
although soil
moisture is likely low
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Gopherus agassizi
desert tortoise
Fed: THR
Cal: THR
NDDB Element Rank:

Global = G3
State = S2S3
MSHCP = Yes (Conserved
Habitat on -site for this
species)
Various desert communities
and habitats (Mojave creosote
bush scrub, Joshua tree
woodland, saltbush scrub);
washes, arroyos, bajadas,
rocky hillsides, open flat desert
Absent
Fine sandy soils and
disturbed and
isolated nature of
site are not suitable
habitat. Soil type
would not be
suitable for burrows.

Phrynosoma mcallii
Flat -tailed horned lizard
F: ND
C: SSC
State rank: S2
CVMSHCP: Yes
Fine sand in desert washes
and flats with vegetative cover
and ants, generally below 600
feet elevation in Riverside,
San Diego, and Imperial
Counties.

Absent
Habitat marginal and
poor quality, sandy
areas are
surrounded by
development and
have been highly
disturbed. CNDDB
records in vicinity
are historic and have
been mostly
developed.

Uma inornata
Coachella Valley fringe -toed
lizard
F = THR
C = END
NDDB Element Rank:

Global = G1O
State = S1
CVMSHCP = Yes
Restricted to sandy areas in
the Coachella Valley; requires
fine, loose, windblown sand
Absent
Although loose
sandy soils are
present, the site is
isolated and
disturbed. Records
in the vicinity are
from the 1994 and
1975.
interspersed with hardpan and
widely spaced desert shrubs
Table 4. Special Status Birds
Species
Status
Habitat
Probability
Nesting: Absent (Project
F: None
C: FP,WL
Forages over rolling foothills,
mountain areas, sage-
site does not support
nesting habitat.

Aquila chrysaetos
NDDB Element Rank:
juniper flats, and desert.
golden eagle
State Rank: S3
Global: G5
Cliff -walled canyons used for
nesting, sometimes large
Foraging: Low (Do not
MSHCP: No
trees in open areas
forage in urban areas
frequently)
Nesting: Absent
No suitable burrows were
observed.

F = BLM Sensitive,
BCC
Foraging: Low
C = SSC (burrows)
Open, dry annual or
Foraging habitat is
Athene cunicularia
NDDB Element Rank:
perennial grassland, deserts
available onsite and on
burrowing owl
Global: G4
State: S3
MSHCP: Yes
& scrublands characterized
by low -growing vegetation
adjacent properties,
however the project site is
isolated from other open
areas and the site has a
high level of dog activity
which would discourage
owls.
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Table 4. Special Status Birds
Species
Status
Habitat
Probability
Dendroica petechia
yellow warbler
F: MBTA, BCC
C: SSC (nesting), F&G
Code
NDDB Element Rank:

Global: G5
State: S3S4
MSHCP: Yes
Riparian forest and
woodland; nests along
Mojave River, Santa Ana
River, Kern River, and many
others in s. Calif.

Nesting: Absent
No suitable habitat.

Foraging: Low
No suitable habitat.

Empidonax traillii extimus
southwestern willow flycatcher
F: END (subspecies),
MBTA
C: END (full species),
F&G Code
NDDB Element Rank:

Global: G5T2
State: S1
MSHCP: Yes
Riparian woodlands
Nesting: Absent
habitat lacking
Foraging: Absent
g g'
habitat lacking
Falco mexicanus
prairie falcon
F = None, BCC
C = WL
NDDB Element
Global = G5
State = S4
MSHCP = No
Breeding sites located on
cliffs, forages far afield even
to marshlands and ocean
shores
Nesting: Absent
(habitat lacking)
Foraging: Low
g g'
may forage over site
Lanius ludovicianus
loggerhead shrike
F: MBTA, BCC
C: SSC (nesting), F&G
Code
NDDB Element Rank:

Global = G4
State = S4
MSHCP = No
Associated with a variety of
vegetation communities
including creosote bush
scrub, Joshua tree
woodland. Nests in trees
and shrubs.

Nesting: Low
low amount of nesting
habitat on site
Foraging: High (common
in region)
Toxostoma lecontei
Le Conte's thrasher
F = BLM Sensitive,
BCC
C = SSC (San Joaquin
population only)
NDDB Element Ranks:

Global = G4
State = S3
MSHCP = Yes (Other
Conserved Habitat and
modeled habitat on -site
for this species)
Desert resident, primarily of
open desert wash, desert
scrub, alkali desert scrub,
and desert succulent scrub
habitats; commonly nests in
a dense, spiny shrub or
densely branched cactus in
desert wash habitat, usually
2-8 feet above ground
Nesting: Absent (Dense,
spiny shrubs lacking
onsite
Foraging: Low
spiny shrubs lacking
onsite
Vireo bellii pusillus
least Bell's vireo
F: END (nesting),
MBTA
C: END (nesting), F&G
Code
NDDB Element Ranks:

Global = G5T2
State = S2
MSHCP = Yes
Willow riparian woodlands
Nesting: Absent
habitat lacking
Foraging: Absent
habitat lacking
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Table 5.

Special Status Mammals
Species
Status
Habitat
Probability
Chaetodipus fallax pallidus
pallid San Diego pocket
mouse
F = None

C - SSC
NDDB Element
Global = G5T34
State = S3S4
MSHCP = No
Desert border areas in
desert wash, desert scrub,
desert succulent scrub,
pinon-juniper, etc.; sandy
herbaceous areas usually
in association with rocks or
coarse gravel.

Low
Onsite habitat is
marginal and contains
no rocky areas.

Corynorhinus townsendii
Townsend's big -eared bat
F = None
C = SSC
NDDB Element
Global = G3G4
State = S2
WBWG = H
MSHCP = No
Generally viewed as a cave -
dwelling species, but the
western subspecies are also
found on/in human -made
structures (e.g. old mine
workings and buildings).

Roosts in open but
extremely sensitive to
human disturbance.

Roosting: Absent
(roosting habitat not
present)
Foraging: Low
Unlikely to forage due to
disturbance and adjacent
development.

Neotoma lepida intermedia
San Diego desert woodrat
F = None
C = SSC
NDDB Element
Global = G5T3T4
State = S3S4
MSHCP = No
The most common habitats
are chaparral, coastal sage
scrub (including Riversidean
sage scrub and Diegan
coastal sage scrub) and
grassland, although this
subspecies also occurs in
desert habitats.

Absent
No nests were observed
onsite
Ovis canadensis nelsoni pop. 2
Peninsular bighorn sheep
DPS
F = END
C = THR
NDDB Element
Global = G4T3O
State = S1
MSHCP = Yes
Optimal habitat includes
steep -walled canyons and
ridges bisected by rocky or
sandy washes with available
water.

Absent
Outside of species range
and no habitat present
Perognathus longimembris bangsi
Palm Springs pocket mouse
F = BLM Sensitive
C = SSC
NDDB Element
Global = G5T2
State = S2
MSHCP = Yes
(modeled habitat
'9 resent)
Desert scrub, sandy,
loosely -packed soils.

Low
Sandy areas present
onsite. The project site is
isolated from other open
areas and the site has a
high level disturbance and
dog activity
Xerospermophilus tereticaudus
round -tailed ground squirrel
F = BLM Sensitive
C = SSC
NDDB Element
Global = G5T2Q
Coachella Valley (Palm Springs) high
State = S2
MSHCP = Yes
(modeled habitat
present)
Sand fields, dunes and
hummocks in Sonoran
creosote bush scrub,
mesquite, saltbush and
desert sink scrub. Also may
occur in course sandy and
pebbly alluvial substrates
along washes.

Low
Sandy areas present
onsite. The project site is
isolated from other open
areas and the site has a
level disturbance and
dog activity. CNDDB
record from less than 1
mi. NW of site but is from
1954. No potential
burrows observed.

Definitions of occurrence probability:

Occurs: Observed on the site by WSP personnel or recorded on -site by other qualified biologists.

High: Observed in similar habitat in region by qualified biologists, or habitat on the site is a type often utilized by the species and the site is within the known range of the species.

Moderate: Reported sightings in surrounding region, or site is within the known range of the species and habitat on the site is a type occasionally used by the species.

Low: Site is within the known range of the species but habitat on the site is rarely used by the species.

Very Low: Species not expected on site, but can not be completely ruled out.

Absent: A focused study failed to detect the species, or no suitable habitat is present. 339

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Definitions of status designations and occurrence probabilities.

Federal designations: (federal Endangered Species Act, US Fish and Wildlife Service):

END: Federally listed, Endangered.

THR: Federally listed, Threatened.

BCC: Bird of Conservation Concern
C: Candidate for Federal listing
ND: Not designated.

State designations: (California Endangered Species Act, California Dept. of Fish and Game) END: State listed, Endangered.

THR: State listed, Threatened.

C: Candidate for State listing
RARE: State listed as Rare (Listed "Rare" animals have been re -designated as Threatened, but Rare plants have retained the Rare designation.)
SSC: Species of Special Concern.

WL: Watch List Species.

ND: Not designated.

CDFW CNDDB rankings: Animals
S1 = Extremely endangered: http://www.cnps.org/programs/Rare Plant/inventory/names.htm), ALL plants on Lists 1A, 1B, 2A, and 2B meet definitions for state listing as threatened or endangered under Secs. 2062 and 2067 (California Endangered Species Act) of the California Department of Fish and Game Code. Certain plants on Lists 3 and 4 do as well.

The CDFW ( http://www.dfc.ca.cov/hcpb/species/t e spp/nat pint consv.shtml) states that plants on Lists 1A, 1B, 2A, and 2B of the CNPS Inventory consist of plants that may qualify for listing, and recommends they be addressed in CEQA projects (CEQA Guidelines Section 15380). However, a plant need not be in the Inventory to be considered a rare, threatened, or endangered species under CEQA. In addition, CDFW recommends, and local governments may require, protection of plants which are regionally significant, such as locally rare species, disjunct populations of more common plants, or plants on the CNPS Lists 3 and 4.

List 1A: Plants presumed extinct in California.

List 1B: Plants rare and endangered in California and throughout their range.

List 2A: Plants presumed extirpated in California, but more common elsewhere.

List 2B: Plants rare, threatened, or endangered in California, but more common elsewhere.

List 3: Plants for which more information is needed.

List 4: Plants of limited distribution; a "watch list." 340

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CA Endemic: Taxa that occur only in California
CNPS Threat Code:
.1 - Seriously endangered in California (over 80% of occurrences threatened / high degree and immediacy of threat) .2 — Fairly endangered in California (20-80% occurrences threatened) .3 — Not very endangered in California (<20% of occurrences threatened, or no current threats known) Note: All List 1A (presumed extinct in California) and some List 3 (need more information- a review list) plants lacking any threat information receive no threat code extension. Also, these Threat Code guidelines represent a starting point in the assessment of threat level. Other factors, such as habitat vulnerability and specificity, distribution, and condition of occurrences, are also considered in setting the Threat Code.

Western Bat Working Group (WBWG) designations:

The Western Bat Working Group is comprised of agencies, organizations and individuals interested in bat research, management and conservation from the 13 western states and provinces. Its goals are (1) to facilitate communication among interested parties and reduce risks of species decline or extinction; (2) to provide a mechanism by which current information on bat ecology, distribution and research techniques can be readily accessed; and (3) to develop a forum to discuss conservation strategies, provide technical assistance and encourage education programs.

H: High: Species which are imperiled or are at high risk of imperilment based on available information on distribution, status, ecology and known threats.

M: Medium: Species which warrant a medium level of concern and need closer evaluation, more research, and conservation actions of both the species and possible threats. A lack of meaningful information is a major obstacle in adequately assessing these species' status and should be considered a threat.

L: Low: Species for which most of the existing data support stable populations, and for which the potential for major changes in status in the near future is considered unlikely. There may be localized concerns, but the overall status of the species is believed to be secure. Conservation actions would still apply for these bats, but limited resources are best used on High and Medium status species.

P: Periphery: This designation indicates a species on the edge of its range, for which no other designation has been determined.

CVMSHCP designations
Yes: Conserved by the CVMSHCP
No: Not Specifically Conserved by the CVMSHCP
C: Considered, but not included in the CVMSHCP
341

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Biological Resources Assessment
May 2024

5.7 Discussion of the Special -status Species Tables
Based on examination of historic aerial photography of the site (on Google Earth Pro), the California fan palm oasis and southern riparian forest are not present at the site or within the vicinity.

5.7.1 CVMSHCP Covered Species
Nineteen of the species listed in Tables 1 — 3 are conserved under the CVMSHCP: Coachella Valley milk -vetch, triple -ribbed milk -vetch, Mecca aster, Little San Bernardino Mountains linanthus, Coachella giant sand treader cricket, Coachella Valley Jerusalem cricket, desert pupfish, desert tortoise, flat -tailed horned lizard, Coachella Valley fringe -toed lizard, burrowing owl, Southwestern willow flycatcher, crissal thrasher Le Contes' thrasher, Least Bell's vireo, western yellow bat, Palm Springs pocket mouse, Coachella Valley (Palm Springs) round -tailed ground squirrel, and Peninsular bighorn sheep. Six of these species are expected to have at least a low to very low probability of occurring on the project site. These include Coachella Valley milk - vetch, Coachella giant sand treader cricket, Coachella Valley Jerusalem cricket, burrowing owl, Palm Springs pocket mouse, and Coachella Valley (Palm Springs) round -tailed ground squirrel.

Participation in the CVMSHCP, and participation in the plan, if required will fully mitigate project related impacts (although none are anticipated) to all of these CVMSHCP covered species with the exception of burrowing owl.

No burrows suitable for burrowing owl use were observed on or adjacent to the project site. Where accessible, adjacent vacant lands were surveyed within 500 feet of the site. No burrowing owls, theft sign, or burrows capable of supporting owls were observed in this buffer area. The burrowing owl is not listed as threatened or endangered by the USFWS or CDFW. It is, however, managed as a Bird of Conservation Concern (BCC) by the USFWS and designated as a SSC by the CDFW.

It is also protected from take by the MBTA and California Fish and Game Code. The burrowing owl is a covered species under the CVMSHCP, however the federal permit for the CVMSHCP does not allow take of this species under the MBTA. For these reasons, all burrowing owls must be avoided or relocated prior to any ground disturbing activities. No burrowing owls, owl sign, or suitable burrows were observed during the survey.

5.7.2 Potentially Occurring Species Not Covered Under the CVMSHCP and USFWS IPAC Species
Seven special status species that are not covered by the CVMSHCP are considered to have at least some potential (low to very low) to occur on or forage over the project site. Prairie falcon are expected to have a low probability to forage over the site (although this would be rare given the developed nature of the site and surrounding area). Prairie falcon is not listed as threatened or endangered by either State or Federal agencies but is considered a "Species of Special Concern" by the California Department of Fish and Wildlife. Slender cottonheads are expected to have a low probability of growing on this site. Slender cottonheads were not observed during the survey.

This plant species is not listed as threatened or endangered and are generally not expected to occur on the site. Still, they could not be absolutely ruled out due to presence of marginally suitable habitat and the seasonal timing of the site visit.

The USFWS IPAC report generated for this project lists five sensitive wildlife species and one plant as having potential to be affected by development of this project. As discussed in Tables 1 — 3 in Section 5.6, none of the listed species are expected to occur onsite. Monarch butterflies require milkweeds for larval development and other flowering plants for adult nectar sources. No milkweed plants were observed on the site. There is no quality habitat present for desert tortoise 342

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Via Vail 3 Apartment Homes Project
Biological Resources Assessment
May 2024
due to the sandy nature of the soil which do not provide good burrowing substrate as well as the high level of disturbance. Suitable habitat for Coachella Valley fringe -toed lizard is present, however the site is highly disturbed and isolated from other open areas. The most recent record in the areas for Coachella Valley fringed -toed lizard are from 1994. Least Bell's vireo is absent from the site due to a lack of any suitable riparian habitat.

6.0 DISCUSSION
The proposed project includes the permanent disturbance of approximately 5 acres of disturbed creosote scrub to build apartment homes.

6.1 Protection of Nesting Birds
All native bird species that are excluded from coverage under the CVMSHCP are still protected by the MBTA and the state Fish and Game Code. This includes virtually all native migratory and resident bird species. Avoidance of impacts to these birds is a requirement of the federal permit issued for the CVMSHCP. To avoid impacting nesting birds either avoidance of project -related disturbance during the nesting season, nesting bird surveys should be conducted by a qualified ornithologist or biologist immediately prior to on -site disturbance. If nesting birds are found, no work would be permitted near the nest until young have fledged. There is no established protocol for nest avoidance, however, when consulted the CDFW generally recommends avoidance buffers of about 500 feet for birds -of -prey and species listed as threatened or endangered, and 100-300 feet for unlisted songbirds.

6.2 Burrowing Owl
As noted above, no burrowing owls or their sign were present on site. Also, no burrows or burrow surrogates that could be used by burrowing owls were present on the site at the time of this survey. This species nests and roosts underground so is uniquely vulnerable to ground disturbing activities. Since no burrowing owl sign or suitable burrows were observed, a search for burrowing owls during the required MBTA survey prior to construction should be sufficient to ensure there are no impacts to burrowing owls. The MBTA survey should be conducted prior to initiating construction to ensure that no nesting birds have moved onto the site in the interim between this survey and project startup. Unless avoidable, all burrowing owls present must be relocated prior to any ground disturbing activities. If burrows are found on -site, a Burrowing Owl Relocation and Management Plan will be prepared to describe and outline how the burrowing owl will be actively or passively relocated per CDFW guidelines. Prior to construction, any owls occurring on -site will be relocated prior to vegetation removal or grading activities. Relocation will require prior permission from the CDFW, at a minimum, but is not anticipated at this time. Since the burrowing owl is a covered species under the CVMSHCP, additional mitigation/conservation measures will not be required.

7.0 CONCLUSION
The project site is highly disturbed and being used as a homeless camp and for local people to run their dogs off leash. No sensitive species were observed within the project area. No nesting bird activity was observed. Suitable nesting habitat is present so a clearance nesting bird survey should be conducted prior to any ground disturbance.
343

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Via Vail 3 Apartment Homes Project
Biological Resources Assessment
May 2024

8.0 LITERATURE CITED AND REFERENCES
California Bird Records Committee. 2023. Official California Checklist. Accessed online at:
httD://californiabirds.orq/ca list.asD.

California Department of Fish and Game (CDFG). 2012. Staff report on Burrowing Owl Mitigation.

CDFG, Sacramento, CA.

California Department of Fish and Wildlife (CDFW). 2024a. California Natural Diversity Data Base, Rarefind 5. Report for the Rancho Mirage, Cathedral City, Palm Springs, Myoma, La Quinta, Toro Peak, and Palm View Peak. quadrangles. Accessed at:
dfg.ca.gov/biogeodata/cnddb/mapsanddata.asp
CDFW. 2024b. Special Animals List. April. Periodic publication. Sacramento, CA. Accessed online at: https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentlD=109406&inline=1 CDFW. 2016. Complete List of Amphibian, Reptile, Bird and Mammal Species in California.

Accessed online at: https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentlD=87155&inline California Legislative Information. 2021. Fish and Game Code of California. https://leginfo.legislature.ca.gov/faces/codesTOCSelected.xhtml?tocCode=FGC&tocTitle =+Fish+and+Game+Code+-+FGC
CDFW. 2015a. California Wildlife Habitat Relationships, Life History Accounts and Range Maps.

Accessed online at: httD:// www.dfc.ca.gov/bioceodata/cwhr/cawildlife.asox CDFW. 2015b. Threatened and Endangered Species, Species Lists and Accounts, Species Accounts -Fish. Accessed online at: https://www.dfg.ca.gov/wildlife/nongame/t e sin/ CDFW. 2016. Complete List of Amphibian, Reptile, Bird and Mammal Species in California.

Accessed online at: nrm.dfg.ca.gov/FileHandler.ashx?DocumentlD=87155&inline=1 California Native Plant Society (CNPS). 2024a. Inventory of Rare, Threatened, and Endangered Plants of California. Report for the Valerie. quadrangles. Accessed online at:
htt
D://www. rareolants.cnps.orc
CNPS. 2024b. The California Rare Plant Ranking System. Accessed online at:
https://www.cnos.orc/cnps/rareolants/ranking . Dho
California Natural Resources Agency. 2014. CEQA Guidelines. Accessed online at:
htt D://resources.ca.cov/cec a/guidelines/
CVAG. 2016. Final Major Amendment to the Coachella Valley Multiple Species Habitat Conservation Plan/Natural Community Conservation Plan. Accessed online at:
https://www.cvmshcp.org/Plan° /020Documents/10.°/020CVAG°/020MSHCP°/020Plan%20S ection°/0203.0.pdf
CVAG. 2008. Coachella Valley Multiple Species Habitat Conservation Plan. Accessed online at:
cvmshcp.org
Holland, R.F. 1986. Preliminary Descriptions of the Terrestrial Natural Communities of California.

Prepared for the California Department of Fish and Game.

Jepson Flora Project (2°d ed.). 2023. Jepson eFlora. Accessed online at:
htto://uc'e Ds.berkeley.edu/IJM.htmI
Sawyer, J.O., T. Keeler -Wolf, and J.M. Evens. 2009. A manual of California vegetation (2' ed.).

California Native Plant Society, Sacramento, CA.

Shuford, W. D., and Gardali, T. (Ed.). 2008. California Bird Species of Special Concern: A ranked assessment of species, subspecies, and distinct populations of birds of immediate 344 Page 17

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Biological Resources Assessment
May 2024
conservation concern in California. Studies of Western Birds 1. Western Field Ornithologists, Camarillo, California, and California Department of Fish and Game, Sacramento.

United States Department of Agriculture (USDA), Soil Conservation Service. 1980. A Soil Survey of Riverside County, California, Coachella Valley Area. https://www.nres.usda.gov/Internet/FSE MAN USCRIPTS/california/riversideCA1980/rive rsideCA1980.pdf
USDA, Natural Resources Conservation Service (NRCS). 2024. The PLANTS Database. National Plant Data Team. Accessed online at: plants.usda.gov
USDA, NRCS. 2024. Web Soil Survey. Accessed online at:
httD://websoilsurvey.nres.usda.gov/app/
USFWS. 2016. Bird Laws and Treaties. Accessed online at:
http://www.fws.cov/migratorybirds/RegulationsandPolicies.html USGS 7.5' Cathedral City, Calif. 7.5 -minute topographic quadrangles (USGS 2021) 345

Page 18 ends

APPENDIX A

FIGURES
346

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Parcel 3 Apartment Homes Project
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Via Vail
Parcel 3 Apartment Homes Project
Coachella Valley, CA

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Soils
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Parcel 3 Apartment Homes Project
Coachella Valley, CA

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Parcel 3 Apartment Homes Project
Coachella Valley, CA

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Via Vail
Parcel 3 Apartment Homes Project
Coachella Valley, CA
351

APPENDIX B

PLANTS AND VERTEBRATE WILDLIFE OBSERVED
352

Vertebrate qpecies Observed
Corvidae
Corvusbrachyrhynchos American crow
Fringillidae
Haemorhousmexicanus house finch
Remiadae
Auriparusflaviceps verdin
Tyrannidae
Sayornis saya
Say's phoebe
353

Amarant haceae
Atriplex canescens
Ast eraceae
Dicoria canescens
Palafoxia arida
Boragi naceae
.bhnstonella angustifolia
Tiquilia plicata
Brassicaceae
Brassica tournefortii
Fabaceae
FSorothamnus emoryi
Geran i aceae
Erodium dcutarium
Loasaceae
Fetalonyx thurberi
Nyct agi naceae
Abronia villosa
Plant jeciesObserved
four -wing saltbush
desert dicoria
Spanish needles
narrow leaved forget me not
fanleaf crinklemat
Sahara mustard
dyebush
red stemmed filaree
sandpaper plant
desert sand verbena
Onagraceae
Chylismia daviformisssp. daviformis browneyes
Zygophyl laceae
Larrea tridentata
Poaceae
Schismus barbatus
creosote bush
old han schismus

APPENDIX C

SITE PHOTOS
355

NW
270 300
I • I • t • I
1 1 NE E
330 30 60 90
• 1• 1• •I •• I• I• I 1• I• I• I• I• 1
Q°N (T) • 33.795757° 1,116.393454°W _±13ft A 318ft
Photo 1. Looking north across the site.

SW NW IV
180 210 240 '0 304 330 0
I• I• I• I• 1• I• I• I• I• I• I• I• I• I• I• I• I I• I
O 269°W (T) 33.796380°N,116.393602°W ± 3ft A 3161
Photo 2. Looking west across the site.
356

90 120 150 111. 210 240 270
I • I • I • I • L • I • I • I • II • I • I • I • II • I • I • I • I • I • I E SE
SW '' f
181°S (T) ': l 33.796258°N,116.393154°W ±13ft • 302ft
Photo 3. Looking west across the site shows a portion of the homeless camp.

I
S
180
• I
SW
210 240 270
• 1• I• I• I• I• 1 I I• I•
NW
300 330
• I• • • I • I • I
O 248°W (T) r• 33.796343°N,116.393425°W ±9ft ► 304ft
FS
Photo 4. Showing annual species within the sandy site.
357

APPENDIX D
CVMSHCP Table 4-112:

Coachella Valley Native Plants Recommended for Landscaping 358

Coachella Valley Native Plants Recommended for Landscaping

BOTANICAL NAME
Trees
Washingtonia filifera
Cercidium floridum
Chilopsis linearis
Olneya tesota
Prosopis glandulosa var. torreyana
Shrubs
Acacia greggii
Ambrosia dumosa
Atriplex canescens
Atriplex lentiformis
Atriplex polycarpa
Baccharis sergiloides
Bebia juncea
Cassia (Senna) covesii
Condalia parryi
Crossosoma bigelovii
Dalea emoryi
Dalea (Psorothamnus) schottii
Datura meteloides
Encelia farinosa
Ephedra aspera
Eriogonum fasciculatum
Eriogonum wrightii membranaceum
Fagonia laevis
Gutierrezia sarothrae
Haplopappus acradenius
Hibiscus denudatus
Hoffmannseggia microphylla
Hymenoclea salsola
Hyptis emoryi
Isomeris arborea
Juniperus californica
Krameria grayi
Krameria parvifolia
Larrea tridentata
Lotus rigidus
Lycium andersonii
Petalonyx linearis
Petalonyx thurberi
Peucephyllum schottii
Prunus fremontii
Rhus ovata
Salazaria mexicana
Salvia apiana
Salvia eremostachya

COMMON NAME
California fan palm
blue palo verde
desert willow
ironwood tree
honey mesquite
cat's claw acacia
burro bush
four wing saltbush
quailbush
cattle spinach
squaw water -weed
sweet bush
desert senna
crucilllo
crossosoma
dye weed
indigo bush
jimson weed
brittle bush
Mormon tea
California buckwheat
Wright's buckwheat
no common name
matchweed
goldenbush
desert hibiscus
rush pea
cheesebush
desert lavender
bladder pod
California juniper
ratany
little -leaved ratany
creosote bush
desert rock pea
box thorn
long -leaved sandpaper plant
sandpaper plant
pygmy cedar
desert apricot
sugar -bush
paper -bag bush
white sage
Santa Rosa sage
359

Salvia vaseyi
Simmondsia chinensis
Sphaeralcia ambigua
Sphaeralcia ambigua rosacea
Trixis californica
Zauschneria californica
Groundcovers
Mirabilis bigelovii
Mirabilis tenuiloba
Vines
Accent
Vitis girdiana
Muhlenbergia rigens
Herbaceous Perennials
Adiantum capillus-veneris
Carex alma
Dalea parryi
Eleocharis montevidensis
Equisetum laevigatum
Juncus bufonis
Juncus effuses
Juncus macrophyllus
Juncus mexicanus
Juncus xiphioides
Notholaena parryi
Pallaea mucronata
Cacti and Succulents
Agave deserti
Asclepias albicans
Asclepias subulata
Dudleya arizonica
Dudleya saxosa
Echinocereus engelmannii
Ferocactus acanthodes
Fouquieria splendens
Mamillaria dioica
Mamillaria tetrancistra
Nolina parryi
Opuntia acanthocarpa
Opuntia bigelovii
Opuntia basilaris
Opuntia echinocarpa
Opuntia ramosissima
Yucca schidigera
Yucca whipplei
wand sage
jojoba
globemallow (desert mallow)
apricot mallow
trixis
California fuchsia
wishbone bush (four o'clock)
white four o'clock (thin -lobed)
desert grape
deer grass
maiden -hair fern
sedge
Parry dalea
spike rush
horsetail
toad rush
juncus
juncus
Mexican rush
juncus
Parry cloak fern
bird -foot fern
desert agave
desert milkweed (buggy -whip)
ajamete
live -forever
rock dudleya
calico hedgehog cactus
barrel cactus
ocotillo
nipple cactus
corkseed cactus
Parry nolina
stag -horn or deer -horn cholla
teddy bear or jumping cholla
beavertail cactus
silver or golden cholla
pencil cholla, darning needle cholla
Mojave yucca, Spanish dagger
Our Lord's candle
360

APPENDIX E
Prohibited Invasive Ornamental Plants
361

Prohibited Invasive Ornamental Plants

BOTANICAL NAME
Acacia spp. (all species except A. greggii)
Arundo donax
Atriplex semibaccata
Avena barbata
Avena fatua
Brassica tournefortii
Bromus madritensis ssp. rubens
Bromus tectorum
Cortaderia jubata [syn. C. atacamensis]
Cortaderia dioica [syn. C. selloana]
Descurainia sophia
Eichhornia crassipes
Elaegnus angustifolia
Foeniculum vulgare
Hirschfeldia incana
Lepidium latifolium
Lolium multiflorum
Nerium oleander
Nicotiana glauca
Oenothera berlandieri
Olea europea
Parkinsonia aculeata
Pennisetum clandestinum
Pennisetum setaceum
Phoenix canariensis
Phoenix dactylifera
Ricinus communis
Salsola tragus
Schinus mole
Schinus terebinthifolius
Schismus arabicus
Schismus barbatus
Stipa capensis
Tamarix spp. (all species)
Taeniatherum caput-medusae
Tribulus terrestris
Vinca major
Washingtonia robusta
Yucca gloriosa

COMMON NAME
(all species except native catclaw
acacia)
giant reed or arundo grass
Australian saltbush
slender wild oat
wild oat
African or Saharan mustard
red brome
cheat grass or downy brome
jubata grass or Andean pampas grass
pampas grass
tansy mustard
water hyacinth
Russian olive
sweet fennel
Mediterranean or short -pod mustard
perennial pepperweed
Italian ryegrass
oleander
tree tobacco
Mexican evening primrose
European olive tree
Mexican palo verde
Kikuyu grass
fountain grass
Canary Island date palm
date palm
castorbean
Russian thistle
Peruvian pepper tree
Brazilian pepper tree
Mediterranean grass
Saharan grass, Abu Mashi
no common name
tamarisk or salt cedar
Medusa -head
puncturevine
periwinkle
Mexican fan palm
Spanish dagger
Sources: California Exotic Pest Plant Council, United States Department of Agriculture -Division of Plant Health and Pest Prevention Services, California Native Plant Society, Fremontia Vol. 26 No. 4, October 1998, The Jepson Manual; Higher Plants of California, and County of San Diego Department of Agriculture. 362

APPENDIX F
USFWS IPaC Report
363

Rancho Mirage Affordable Housing Family Apartments
Initial Study/Mitigated Negative Declaration
May 2025
Appendix C
Historical/Archaeological Resources Survey Report
City of Rancho Mirage C
364

HISTORICAL/ARCHAEOLOGICAL RESOURCES SURVEY REPORT
ASSESSOR'S PARCEL NUMBER 685-090-016
City of Rancho Mirage
Riverside County, California
For Submittal to:

Development Services Department, Planning Division
City of Rancho Mirage
69825 Highway 111
Rancho Mirage, CA 92270
Prepared for:

Terra Nova Planning and Research, Inc.
42635 Melanie Place, Suite 101
Palm Desert, CA 92211
Prepared by:

CRM TECH
1016 East Cooley Drive, Suite A/B
Colton, CA 92324
Bai "Tom" Tang, Principal Investigator
Michael Hogan, Principal Investigator
July 1, 2024
CRM TECH Contract No. 4127
365

Title: Historical/Archaeological Resources Survey: Assessor's Parcel Number 685-090-016, City of Rancho Mirage, Riverside County, California Author(s): Bai "Tom" Tang, Principal Investogator/Historian Frank Raslich, Archaeologist/Report Writer
Michael Richards, Archaeologist
Consulting Firm:

Date:

For Submittal to:

Prepared for:

Project Size:

USGS Quadrangle:

CRM TECH
1016 East Cooley Drive, Suite A/B
Colton, CA 92324
(909) 824-6400
July 1, 2024
Development Services Department, Planning Division
City of Rancho Mirage
69825 Highway 111
Rancho Mirage, CA 92270
(760) 328-2266
Nicole Criste, Vice President
Terra Nova Planning and Research, Inc.
42635 Melanie Place, Suite 101
Palm Desert, CA 92211
(760) 320-9811
Approximately five acres
Cathedral City, Calif., 7.5' quadrangle (Section 30, T4S R6E, San Bernardino Baseline and Meridian)
Keywords: Coachella Valley region, western Colorado Desert; no "historical resources" under CEQA
366

EXECUTIVE SUMMARY
Between April and July 2024, at the request of Terra Nova Planning and Research, Inc., CRM TECH performed a cultural resources survey on approximately five acres of vacant desert land in the northeastern portion of the City of Rancho Mirage, Riverside County, California. The subject property of the study, Assessor's Parcel Number 685- 090-016, is located to the south of Dinah Shore Drive and between Monterey Avenue and Key Largo Avenue, in the northeast quarter of Section 30, T4S R6E, San Bernardino Baseline and Meridian.

The study is a part of the environmental review process for a proposed housing development project on the property. The City of Rancho Mirage, as the lead agency for the project, required the study in compliance with the California Environmental Quality Act (CEQA). The purpose of the study is to provide the City with the necessary information and analysis to determine whether the proposed project would cause substantial adverse changes to any "historical resources," as defined by CEQA, that may exist in or around the project area.

In order to identify such resources, CRM TECH reviewed the results of a recent historical/archaeological resources records search on an adjacent property, contacted pertinent Native American representatives, pursued historical background research, and carried out an intensive -level field survey. Throughout the course of these research procedures, no cultural resources of prehistoric or historic origin were encountered within or adjacent to the project area. Therefore, CRM TECH recommends to the City of Rancho Mirage a finding that the proposed project will have No Impact on any "historical resources."
No further cultural resources investigation is recommended for the project unless development plans undergo such changes as to include areas not covered by this study.

However, if buried cultural materials are discovered during any earth -moving operations associated with the project, all work in the immediate area should be halted or diverted until a qualified archaeologist can evaluate the nature and significance of the finds.
367

TABLE OF CONTENTS
EXECUTIVE SUMMARY i
INTRODUCTION 1
SETTING 4
Current Natural Setting 4
Cultural Setting 4
Prehistoric Context 4
Ethnohistoric Context 5
Historic Context 7
RESEARCH METHODS 7
Records Search 7
Native American Participation 8
Historical Background Research 8
Field Survey 8
RESULTS AND FINDINGS 9
Records Search 9
Native American Participation 9
Historical Background Research 10
Field Survey 11
DISCUSSION 11
CONCLUSIONS AND RECOMMENDATIONS 12
REFERENCES 13
APPENDIX 1: Personnel Qualifications 15
APPENDIX 2: Native American Responses 19

LIST OF FIGURES
Figure 1. Project vicinity 1
Figure 2. Project area 2
Figure 3. Recent satellite image of the project area 3
Figure 4. Typical landscape in the project area 4
Figure 5. The project area and vicinity in 1855-1856 10 Figure 6. The project area and vicinity in 1901 10
Figure 7. The project area and vicinity in 1941 11
Figure 8. The project area and vicinity in 1951-1958 11 36$

INTRODUCTION
Between April and July 2024, at the request of Terra Nova Planning and Research, Inc., CRM 1'LCH performed a cultural resources survey on approximately five acres of vacant desert land in the northeastern portion of the City of Rancho Mirage, Riverside County, California (Fig. 1). The subject property of the study, Assessor's Parcel Number 685-090-016, is located to the south of Dinah Shore Drive and between Monterey Avenue and Key Largo Avenue, in the northeast quarter of Section 30, T4S R6E, San Bernardino Baseline and Meridian (Figs. 2, 3).

The study is a part of the environmental review process for a proposed housing development project on the property. The City of Rancho Mirage, as the lead agency for the project, required the study in compliance with the California Environmental Quality Act (CEQA; PRC §21000, et seq.). The purpose of the study is to provide the City with the necessary information and analysis to determine whether the proposed project would cause substantial adverse changes to any "historical resources," as defined by CEQA, that may exist in or around the project area.

Project
location
Figure 1. Project vicinity. (Based on USGS Santa Ana, Calif., 120'x60' quadrangle [USGS 1979]) l
369

\ \
Project
area
SCALE 1:24,000
1/2
1000 0 1000 2000 3000 4000 feet
Figure 2. Project area. (Based on USGS Cathedral City and Myoma, Calif., 7.5' quadrangles [USGS 1978; 1981]) 2 370

Figure 3. Recent satellite image of the project area. (Based on Google Earth imagery) 3731

SETTING

CURRENT NATURAL SETTING
The City of Rancho Mirage is located in the Coachella Valley, a northwest -southeast trending desert valley that constitutes the western end of the Colorado Desert. Dictated by this geographic setting, the climate and environment of the region are typical of the southern California desert country, marked by extremes in temperature and aridity. Temperatures in the region reach over 120 degrees Fahrenheit in summer, and dip to near freezing in winter. Average annual precipitation is less than five inches, and the average annual evaporation rate exceeds three feet.

The rectangular shaped project area lies on a generally level and sandy desert ridge between the San Jacinto Mountains to the southwest and the Indio Hills to the northeast. It is surrounded by other parcels of vacant land of similar character, with the Monterey Marketplace shopping center further to the north and a residential neighborhood to the west across Kay Largo Avenue (Fig. 3). Elevations in the project area range roughly from 300 feet to 315 feet above mean sea level, with the terrain sloping gently downward to the northeast. Vegetation in the project area consists of a scattered growth of native plants, mainly creosote bushes and other small desert shrubs and grasses.

Figure 4. Typical landscape in the project area, view to the southwest. (Photograph taken on May 14, 2024)

CULTURAL SETTING
Prehistoric Context
Numerous investigations on the history of cultural development in southern California have led researchers to propose a number of cultural chronologies for the desert regions. A specific cultural sequence for the Colorado Desert was offered by Schaefer (1994) on the basis of the many archaeological studies conducted in the area. The earliest time period identified is the Paleoindian 4 372

(ca. 8,000 to 10,000-12,000 years ago), when "small, mobile bands" of hunters and gatherers, who relied on a variety of small and large game animals as well as wild plants for subsistence, roamed the region (Schaefer 1994:63). These small groups settled "on mesas and terraces overlooking larger washes" (Schaefer 1994:64). The artifact assemblage of that period typically consists of very simple stone tools, "cleared circles, rock rings, [and] some geoglyph types" (Schaefer 1994).

The Early Archaic Period follows and dates to ca. 8,000 to 4,000 years ago. It appears that a decrease in population density occurred at this time and that the indigenous groups of the area relied more on foraging than hunting. Very few archaeological remains have been identified to this time period. The ensuing Late Archaic Period (ca. 4,000 to 1,500 years ago) is characterized by continued low population densities and groups of "flexible" sizes that settled near available seasonal food resources and relied on "opportunistic" hunting of game animals. Groundstone artifacts for food processing were prominent during this time period.

The most recent period in Schaefer's scheme, the Late Prehistoric, dates from ca. 1,500 years ago to the time of the Spanish missions, saw the continuation of the seasonal settlement pattern. Peoples of the Late Prehistoric Period were associated with the Patayan cultural pattern and relied more heavily on the availability of seasonal "wild plants and animal resources" (Schaefer 1994:66). It was during this period that ceramics and the bow/arrow were introduced into the region.

The shores of Holocene Lake Cahuilla, during times of its presence, attracted much settlement and resource procurement activities. In times of the lake's desiccation and absence, according to Schaefer (1994:66), the Native people moved away from its receding shores towards rivers, streams, and mountains. Numerous archaeological sites dating to the last high stand of Holocene Lake Cahuilla, roughly between 1600 and 1700 A.D., have been identified along its former shoreline.

Testing and mitigative excavations at these sites have recovered brown and buff ware ceramics, a variety of goundstone and projectile point types, ornaments, and cremation remains.

Ethnohistoric Context
The Coachella Valley is a historical center of Native American settlement, where U.S. surveyors noted large numbers of Indian villages and rancherias, occupied by the Cahuilla people, in the mid - 19th century. The origin of the name "Cahuilla" is unclear, but may originate from their own word kkwiya, meaning master or boss (Bean 1978). The Takic-speaking Cahuilla are generally divided by anthropologists into three groups, according to their geographic setting: the Pass Cahuilla of the San Gorgonio Pass -Palm Springs area, the Mountain Cahuilla of the San Jacinto and Santa Rosa Mountains and the Cahuilla Valley, and the Desert Cahuilla of the eastern Coachella Valley. The basic written sources on Cahuilla culture and history include Kroeber (1925), Strong (1929), and Bean (1978), based on information provided by such Cahuilla informants as Juan Siva, Francisco Patencio, Katherine Siva Saubel, and Mariano Saubel. The following ethnohistoric discussion is based primarily on these sources.

The Cahuilla did not have a single name that referred to an all-inclusive tribal affiliation. Instead, membership was in terms of lineages or clans. Each lineage or clan belonged to one of two main divisions of the people, known as moieties. Their moieties were named for the Wildcat, or Tuktum, and Coyote, or Istam. Members of clans in one moiety had to marry into clans from the other 3753

moiety. Individual clans had villages, or central places, and territories they called their own, for purposes of hunting game, and gathering raw materials for food, medicine, ritual, or tool use. They interacted with other clans through trade, intermarriage, and ceremonies.

Cahuilla subsistence was defined by the surrounding landscape and primarily based on the hunting and gathering of wild and cultivated foods, exploiting nearly all of the resources available in a highly developed seasonal mobility system. They were adapted to the arid conditions of the desert floor, the lacustral cycles of Holocene Lake Cahuilla, and the environments of the nearby mountains. When the lake was full, or nearly full, the Cahuilla would take advantage of the resources presented by the body of fresh water, building elaborate stone fish traps. Once the lake had desiccated, they relied on the available terrestrial resources. The cooler temperatures and resources available at higher elevations in the nearby mountains were also taken advantage of.

The Cahuilla diet included seeds, roots, wild fruits and berries, acorns, wild onions, piflon nuts, and mesquite and screw beans. Medicinal plants such as creosote, California sagebrush, yerba buena and elderberry were typically cultivated near villages (Bean and Saubel 1972). Common game animals included deer, antelope, big horn sheep, rabbits, wood rats and, when Holocene Lake Cahuilla was present, fish and waterfowl. The Cahuilla hunted with throwing sticks, clubs, nets, traps, and snares, as well as bows and arrow (Bean 1978; CSRI 2002). Common tools included manos and metates, mortars and pestles, hammerstones, fire drills, awls, arrow -straighteners, and stone knives and scrapers. These lithic tools were made from locally sourced material as well as materials procured through trade or travel. They also used wood, horn, and bone spoons and stirrers; baskets for winnowing, leaching, grinding, transporting, parching, storing, and cooking; and pottery vessels for carrying water, storage, cooking, and serving food and drink (Bean 1978; CSRI 2002).

As the landscape defined their subsistence practices, the tending and cultivation practices of the Cahuilla helped shape the landscape. Biological studies have recently found evidence that the fan palms found in the Coachella Valley and throughout the southeastern California desert (Washingtonia filifera) may not be relics from a paleo-tropical environment, but instead a relatively recent addition brought to the area and cultivated by native populations (Anderson 2005). The planting of palms by the Cahuilla is well -documented, as is their enhancement of palm stands through the practice of controlled burning (Anderson 2005; Bean and Saubel 1972). Burning palm stands would increase fruit yield dramatically by eliminating pests such as the palm borer beetle, date scales, and spider mites (Bean and Saubel 1972). It also prevented out -of -control wildfires by eliminating dead undergrowth before it accumulated to dangerous levels. The Cahuilla also burned stands of chia to produce higher yields, and deergrass to yield straighter, more abundant stalks for basketry (Bean and Saubel 1972; Anderson 2005).

Population data prior to European contact is almost impossible to obtain, but estimates range from 3,600 to as high as 10,000 persons covering a territory of over 2,400 square miles. During the 19th century, the Cahuilla population was decimated as a result of European diseases, most notably smallpox, for which the Native peoples had no immunity. Today, Native Americans of Pass or Desert Cahuilla heritage are mostly affiliated with one or more of the Indian reservations in and near the Coachella Valley, including Agua Caliente, Morongo, Cabazon, Torres Martinez, and Augustine.

There has been a resurgence of traditional ceremonies in recent years, and the language, songs, and stories are now being taught to the youngest generations. 3764

Historic Context
In 1823-1825, Jose Romero, Jose Maria Estudillo, and Romualdo Pacheco became the first noted European explorers to travel through the Coachella Valley when they led a series of expeditions in search of a route to Yuma (Johnston 1987:92-95). Due to its harsh environment, few non -Indians ventured into the desert valley during the Mexican and early American periods, except those who traveled along the established trails. The most important of these trails was the Cocomaricopa Trail, an ancient Indian trading route that was "discovered" in 1862 by William David Bradshaw and known after that as the Bradshaw Trail (Gunther 1984:71; Ross 1992:25). In much of the Coachella Valley, this historic wagon road traversed a similar course to that of present-day State Route 111.

During the 1860s -1870s, the Bradshaw Trail served as the main thoroughfare between coastal southern California and the Colorado River, until the completion of the Southern Pacific Railroad in 1876-1877 brought an end to its heyday (Johnston 1987:185).

Non -Indian settlement in the Coachella Valley began in the 1870s with the establishment of railroad stations along the Southern Pacific Railroad, and spread further in the 1880s after public land was opened for claims under the Homestead Act, the Desert Land Act, and other federal land laws (Laflin 1998:35-36; Robinson 1948:169-171). Farming became the dominant economic activity in the valley thanks to the development of underground water sources, often in the form of artesian wells. Around the turn of the century, the date palm was introduced into the Coachella Valley, and by the late 1910s dates were the main agricultural crop and the tree an iconic image celebrating the region as the "Arabia of America" (Shields Date Gardens 1957). Then, starting in the 1920s, a new industry featuring equestrian camps, resorts, hotels, and eventually country clubs began to spread throughout the Coachella Valley, transforming it into southern California's premier winter retreat.

In the Rancho Mirage area, the first notable settlement activities occurred in the 1910s -1920s, when several date ranches were established within the present-day city boundary (Love and Tang 1996:7).

In 1924, R.P. "Bert" Davie and E.E. McIntyre subdivided the Rancho Rio del Sol Estates around today's Clancy Lane, creating a small community nicknamed "Little Santa Monica" (Love and Tang 1996:8). Ten years later, Louis Blankenhorn and Laurence Macomber began a new subdivision at the mouth of Magnesia Spring Canyon, and for the first time bestowed the name Rancho Mirage on the community (Love and Tang 1996). After the end of WWII, Rancho Mirage embarked on a period of rapid growth. With the development of the Thunderbird Country Club and the Tamarisk Country Club in 1951-1952, Rancho Mirage set the trend in the post -WWII boom among the five cove communities along Highway 111 (Love and Tang 1996:8-9). This trend has continued into the present and has given rise to the City of Rancho Mirage's popular reputation as the "country club city."

RESEARCH METHODS

RECORDS SEARCH
The historical/archaeological resources records search results used for this study was prepared for an adjacent property to the north (now Assessor's Parcel Number 685-090-017). The records search 3775

was conducted by CRM TECH archaeologist Nina Gallardo on February 9, 2024, at the Eastern Information Center (EIC) of the California Historical Resources Information System. Located on the campus of the University of California, Riverside, the EIC is the State of California's official cultural resource records repository for the County of Riverside.

In addition, CRM TECH also reviewed the results of other records searches completed nearby in recent years to compile a complete inventory of previously identified cultural resources and existing cultural resources reports within a one -mile radius of the current project location. Previously identified cultural resources include properties designated as California Historical Landmarks, Points of Historical Interest, or Riverside County Historic Landmarks, as well as those listed in the National Register of Historic Places, the California Register of Historical Resources, or the California Historical Resources Inventory.

NATIVE AMERICAN PARTICIPATION
On April 16, 2024, CRM TECH submitted a written request to the State of California Native American Heritage Commission (NAHC) for a records search in the commission's Sacred Lands File. The NAHC is the State of California's trustee agency for the protection of "tribal cultural resources," as defined by California Public Resources Code §21074, and is tasked with identifying and cataloging properties of Native American cultural value throughout the state. In the meantime, CRM TECH contacted the nearby Agua Caliente Band of Cahuilla Indians for additional information on potential Native American cultural resources in the vicinity and invited tribal participation in the upcoming archaeological field survey. Responses from the NAHC and the Agua Caliente Band are attached to this report in Appendix 2 and summarized in the sections below.

HISTORICAL BACKGROUND RESEARCH
Historical background research for this study was conducted by CRM TECH archaeologist Frank Raslich. Sources consulted during the research included published literature in local history, historical maps of the Coachella Valley area, and aerial/satellite photographs of the project vicinity.

Among the maps consulted for this study were the U.S. General Land Office's (GLO) land survey plat maps dated 1856 and the U.S. Geological Survey's (USGS) topographic maps dated 1904-1981, which are available at the websites of the U.S. Bureau of Land Management and the USGS. The aerial and satellite photographs, taken in 1959-2024, are accessed at the Nationwide Environmental Title Research (NETR) Online website and through the Google Earth software.

FIELD SURVEY
On May 14, 2024, CRM TECH archaeologist Michael Richards carried out the field survey of the project area with the assistance of Native American monitors Luz Salazar and Xitlaly Madrigal from the Agua Caliente Band of Cahuilla Indians. The survey was conducted at an intensive level by walking a series of parallel north -south transects at 15 -meter (approximately 50 -foot) intervals. In this way, the entire project area was systematically and carefully examined for any evidence of human activities dating to the prehistoric or historic period (i.e., 50 years or older). Ground visibility was good (above 75%) throughout the course of the survey (Fig. 4). 3786

RESULTS AND FINDINGS

RECORDS SEARCH
According to EIC records, the project area had not been surveyed systematically for cultural resources prior to this study, and no cultural resources had been recorded within or adjacent to the project boundaries. Within the one -mile scope of the records search, EIC records identify a total of 35 previously completed cultural resources studies on various tracts of land and linear features. In addition, in April 2024 CRM TECH completed a similar study on the adjacent property to the north, which is yet to be incorporated into EIC records.

As a result of the past survey efforts, 17 cultural resources within the one -mile radius have been recorded into the California Historical Resources Inventory, including four prehistoric (i.e., Native American) sites, seven historic -period sites, and six isolates (i.e., localities with fewer than three artifacts), as listed below in Table 1. The nearest among these, Site 33-017008, was located roughly a half -mile northwest of the project area and consisted of the remains of a collapsed shed of unknown age. Since none of the 17 known cultural resources was found in close proximity to the project location, none of them requires further consideration during this study.

Table 1. Previously Recorded Cultural Resources within the Scope of the Records Search Primary
Number
Trinomial
Description
Date
Recorded
33-003440
CA-RIV-3440H
Remains of Edom Station and Siding on Southern Pacific Railroad 1999
33-005625
N/A
Remains of Kubic Ranch
2004
33-009498
CA-RIV-6381H
Southern Pacific (now Union Pacific) Railroad
2005
33-009748
CA-RIV-6495H
Early alignment of Rio del Sol Road (now Bob Hope Drive), ca. 1941-1958
2000
33-010953
N/A
Two sanitary cans
2000
33-010954
N/A
Sanitary can
2000
33-010955
N/A
Sanitary can
2000
33-010956
N/A
Sanitary can
2000
33-015933
N/A
Beer cans from a six --pack
2000
33-017005
CA-RIV-8852H
Refuse scatter
2007
33-017007
CA-RIV-8854
Scattered groundstone and flaked -stone artifacts
2007
33-017008
CA-RIV-8855H
Remains of collapsed wood -and -metal shed
2007
33-017009
CA-RIV-8856
Cremation remains
2007
33-017010
CA-RIV-8857
Cremation remains with associated lithic artifacts
2007
33-017011
CA-RIV-8858
Scattered groundstone and flaked -stone artifacts
2007
33-017012
N/A
Pottery sherd
2007
33-026824
CA-RIV-12609H
Refuse scatter
2017

NATIVE AMERICAN PARTICIPATION
In response to CRM TECH's inquiry, the NAHC reported in a letter dated May 6, 2024, that the Sacred Lands File search yielded negative results for Native American cultural resources in the project vicinity. Noting that the absence of specific information would not necessarily indicate the absence of cultural resources, however, the NAHC recommended that local Native American groups be consulted for further information and provided a referral list of potential contacts in the region who may have knowledge of such resources. The NAHC's reply is attached in Appendix 2 for 3797

reference by the City of Rancho Mirage in future government -to -government consultations with the pertinent Native American representatives, if necessary.

On April 22, 2024, Xitlaly Madrigal, Cultural Resources Analyst with the Agua Caliente Tribal Historic Preservation Office, replied to CRM TECH in writing. In the letter, she identified the project location as a part of the tribe's Traditional Use Area and requested to review all cultural resources documentation generated for this project, including the records search results. In addition, she requested that a qualified archaeologist perform a cultural resources inventory prior to development and an approved Agua Caliente Native American Cultural Resource Monitor be present during any ground -disturbing activities in the project area (see Appendix 2). As mentioned above, representatives of the Agua Caliente Tribal Historic Preservation Office subsequently participated in the archaeological field survey on May 14, 2024.

HISTORICAL BACKGROUND RESEARCH
Historical sources consulted for this study yielded no evidence of any settlement or development activities within the project area throughout the historic period (Figs. 5-8; NETR Online 1959-1979).

In the late 19th and early 20th centuries, the nearest human -made feature known to be extant was the Southern Pacific (now Union Pacific) Railroad, which was later joined by U.S. Highway 60/70/99, the forerunner of today's Interstate Highway 10 (Figs. 6, 7). By the 1950s, some scattered buildings had appeared in the vicinity, but none of them was located within or adjacent to the project boundaries (Fig. 8; NETR Online 1959). Since the 1990s, real estate development has accelerated noticeably in the surrounding area, as exemplified by the construction of the Monterey Marketplace a
,:1(J •j
Project
area
veep Y+� rry
-.tdJ,fn , n
i1 30
.drr
-14o
2000 4000 feet
4n
Figure 5. The project area and vicinity in 1855-1856.
(Source: GLO 1856a; 1856b)
No coverage
Jr�
Project
area
• 's
SCALE 1:125,000
0 1 2 mites
Figure 6. The project area and vicinity in 1901. (Source:

USGS 1904)
3��

Figure 7. The project area and vicinity in 1941. (Source:

USGS 1941)
Figure 8. The project area and vicinity in 1951-1958.
(Source: USGS 1958)
shopping center and the residential tracts on the west side of Key Largo Avenue (NETR Online 1959-2005). In contrast, the project area has remained unsettled, undeveloped, and evidently unused to the present time (NETR Online 1959-2020).

FIELD SURVEY
The field survey of the project area produced negative results for potential "historical resources." Throughout the course of the survey, no buildings, structures, objects, sites, features, or artifact deposits of prehistoric or historical origin were encountered. Scattered refuse was noted over portions of the property, but all the items are clearly modern in origin, evidently associated with a homeless encampment nearby, and none of them is of any historical/archaeological interest.

DISCUSSION
The purpose of this study is to identify any cultural resources within the project area and to assist the City of Rancho Mirage in determining whether such resources meet the official definition of "historical resources," as provided in the California Public Resources Code, in particular CEQA.

According to PRC §5020.1(j), "`historical resource' includes, but is not limited to, any object, building, site, area, place, record, or manuscript which is historically or archaeologically significant, or is significant in the architectural, engineering, scientific, economic, agricultural, educational, social, political, military, or cultural annals of California." 3��

More specifically, CEQA guidelines state that the term "historical resources" applies to any such resources listed in or determined to be eligible for listing in the California Register of Historical Resources, included in a local register of historical resources, or determined to be historically significant by the lead agency (Title 14 CCR §15064.5(a)(1)-(3)). Regarding the proper criteria for the evaluation of historical significance, CEQA guidelines mandate that "generally a resource shall be considered by the lead agency to be `historically significant' if the resource meets the criteria for listing on the California Register of Historical Resources" (Title 14 CCR § 15064.5(a)(3)). A resource may be listed in the California Register if it meets any of the following criteria:
(1) Is associated with events that have made a significant contribution to the broad patterns of California's history and cultural heritage.
(2) Is associated with the lives of persons important in our past. (3) Embodies the distinctive characteristics of a type, period, region, or method of construction, or represents the work of an important creative individual, or possesses high artistic values.
(4) Has yielded, or may be likely to yield, information important in prehistory or history. (PRC §5024.1(c))
As discussed above, no potential "historical resources" were previously recorded within or adjacent to the project area, and none was found during the present survey. The Native American Sacred Lands File identified no properties of traditional cultural value in the vicinity, and no notable cultural features were known to be present in the project area throughout the historic period. Based on these findings, and in light of the criteria listed above, the present study concludes that no "historical resources" exist within or adjacent to the project area.

CONCLUSIONS AND RECOMMENDATIONS
CEQA establishes that "a project that may cause a substantial adverse change in the significance of a historical resource is a project that may have a significant effect on the environment" (PRC §21084.1). "Substantial adverse change," according to PRC §5020.1(q), "means demolition, destruction, relocation, or alteration such that the significance of a historical resource would be impaired."
In conclusion, the present study has identified no "historical resources" within or adjacent to the project area. Therefore, CRM TECH presents the following recommendations to the City of Rancho Mirage:
• The proposed project will not cause a substantial adverse change to any known "historical resources."
• No further cultural resources investigation is necessary for the project unless development plans undergo such changes as to include areas not covered by this study. • If buried cultural materials are discovered during any earth -moving operations associated with the project, all work in the immediate area should be halted or diverted until a qualified archaeologist can evaluate the nature and significance of the find. 3816

REFERENCES
Anderson, M. Kat
2005 Tending the Wild: Native American Knowledge and the Management of California's Natural Resources. University of California Press, Berkeley.

Bean, Lowell John
1978 Cahuilla. In Robert F. Heizer (ed.): Handbook of North American Indians, Vol. 8:

California; pp. 575-587. Smithsonian Institution, Washington, D.C.

Bean, Lowell John, and Katherine Siva Saubel
1972 Temalpakh: Cahuilla Indian Knowledge and Usage of Plants. Malki Museum Press, Banning, California.

CSRI (Cultural Systems Research, Inc.)
2002 The Native Americans of Joshua Tree National Park: An Ethnographic Overview and Assessment Study. Http:// www.cr.nps.gov/history/online_books/jotr/history6.htm .

GLO (General Land Office, U.S. Department of the Interior) 1856a Plat map: Township No. 4 South Range No. 5 East, SBBM; surveyed in 1855-1856. 1856b Plat map: Township No. 4 South Range No. 6 East, SBBM; surveyed in 1855-1856.

Gunther, Jane Davies
1984 Riverside County, California, Place Names: Their Origins and Their Stories. J.D.

Gunther, Riverside.

Johnston, Francis J.
1987 The Bradshaw Trail; revised edition. Historical Commission Press, Riverside.

Kroeber, Alfred L.
1925 Handbook of the Indians of California. Bureau of American Ethnology Bulletin 78.

Government Printing Office, Washington, D.C.

Laflin, Patricia
1998 Coachella Valley California: A Pictorial History. The Donning Company, Virginia Beach, Virginia.

Love, Bruce, and Bai "Tom" Tang
1996 Cultural Resources Report: Rancho Mirage General Plan, City of Rancho Mirage, Riverside County, California. On File, Eastern Information Center, University of California, Riverside.

NETR (Nationwide Environmental Title Research) Online
1959-2020 Aerial photographs of the project vicinity; taken in 1959, 1972, 1977, 1979, 1984, 1996, 2002, 2005, 2009, 2010, 2012, 2014, 2016, 2018, and 2020. http://www.historicaerials.com .

Robinson, W.W.
1948 Land in California. University of California Press, Berkeley.

Ross, Delmer G.
1992 Gold Road to La Paz: An Interpretive Guide to the Bradshaw Trail. Tales of the Mojave Road Publishing Company, Essex, California.

Schaefer, Jerry
1994 The Challenge of Archaeological Research in the Colorado Desert: Recent Approaches and Discoveries. Journal of California and Great Basin Anthropology 16(1):60-80. 381

Shields Date Gardens
1957 Coachella Valley Desert Trails and the Romance and Sex Life of the Date. Shields Date Gardens, Indio.

Strong, William Duncan
1929 Aboriginal Society in Southern California. University of California Publications in American Archaeology and Ethnology, Vol. 26.

USGS (United States Geological Survey, U.S. Department of the Interior) 1904 Map: Indio, Calif. (30', 1:125,000); surveyed in 1901. 1941 Map: Edom, Calif. (15', 1:62,500); aerial photographs taken in 1941. 1958 Map: Thousand Palms, Calif. (15', 1:62,500); aerial photographs taken in 1951-1956, field -checked in 1958.
1978 Map: Myoma, Calif. (7.5', 1:24,000); 1958 edition photorevised in 1972, photoinspected in 1978.
1979 Map: Santa Ana, Calif. (120'x60', 1:250,000); 1959 edition revised. 1981 Map: Cathedral City, Calif. (7.5', 1:24,000); 1958 edition photorevised in 1978. 3s'�

APPENDIX 1:

PERSONNEL QUALIFICATIONS

PRINCIPAL INVESTIGATOR/HISTORIAN
Bai "Tom" Tang, M.A.

Education
1988-1993 Graduate Program in Public History/Historic Preservation, University of California, Riverside.
1987 M.A., American History, Yale University, New Haven, Connecticut. 1982 B.A., History, Northwestern University, Xi'an, China. 2000 "Introduction to Section 106 Review," presented by the Advisory Council on Historic Preservation and the University of Nevada, Reno.
1994 "Assessing the Significance of Historic Archaeological Sites," presented by the Historic Preservation Program, University of Nevada, Reno.

Professional Experience
2002- Principal Investigator, CRM TECH, Riverside/Colton, California. 1993-2002 Project Historian/Architectural Historian, CRM TECH, Riverside, California. 1993-1997 Project Historian, Greenwood and Associates, Pacific Palisades, California. 1991-1993 Project Historian, Archaeological Research Unit, University of California, Riverside. 1990 Intern Researcher, California State Office of Historic Preservation, Sacramento. 1990-1992 Teaching Assistant, History of Modern World, University of California, Riverside. 1988-1993 Research Assistant, American Social History, University of California, Riverside. 1985-1988 Research Assistant, Modern Chinese History, Yale University. 1985-1986 Teaching Assistant, Modern Chinese History, Yale University. 1982-1985 Lecturer, History, Xi'an Foreign Languages Institute, Xi'an, China.

Cultural Resources Management Reports
Preliminary Analyses and Recommendations Regarding California's Cultural Resources Inventory System (with Special Reference to Condition 14 of NPS 1990 Program Review Report). California State Office of Historic Preservation working paper, Sacramento, September 1990.

Numerous cultural resources management reports with the Archaeological Research Unit, Greenwood and Associates, and CRM TECH, since October 1991. 381

PRINCIPAL INVESTIGATOR/ARCHAEOLOGIST
Michael Hogan, Ph.D., RPA (Registered Professional Archaeologist) Education
1991 Ph.D., Anthropology, University of California, Riverside. 1981 B.S., Anthropology, University of California, Riverside; with honors. 1980-1981 Education Abroad Program, Lima, Peru.
2002 "Section 106 —National Historic Preservation Act: Federal Law at the Local Level," UCLA Extension Course #888.
2002 "Recognizing Historic Artifacts," workshop presented by Richard Norwood, Historical Archaeologist.
2002 "Wending Your Way through the Regulatory Maze," symposium presented by the Association of Environmental Professionals.
1992 "Southern California Ceramics Workshop," presented by Jerry Schaefer. 1992 "Historic Artifact Workshop," presented by Anne Duffield -Stoll.

Professional Experience
2002- Principal Investigator, CRM TECH, Riverside/Colton, California. 1999-2002 Project Archaeologist/Field Director, CRM TECH, Riverside, California. 1996-1998 Project Director and Ethnographer, Statistical Research, Inc., Redlands, California. 1992-1998 Assistant Research Anthropologist, University of California, Riverside. 1992-1995 Project Director, Archaeological Research Unit, U.C. Riverside. 1993-1994 Adjunct Professor, Riverside Community College, Mt. San Jacinto College, U.C.

Riverside, Chapman University, and San Bernardino Valley College. 1991-1992 Crew Chief, Archaeological Research Unit, U.C. Riverside. 1984-1998 Project Director, Field Director, Crew Chief, and Archaeological Technician for various southern California cultural resources management firms.

Research Interests
Cultural Resource Management, Southern Californian Archaeology, Settlement and Exchange Patterns, Specialization and Stratification, Culture Change, Native American Culture, Cultural Diversity.

Cultural Resources Management Reports
Principal investigator for, author or co-author of, and contributor to numerous cultural resources management study reports since 1986.

Memberships
Society for American Archaeology; Society for California Archaeology; Pacific Coast Archaeological Society; Coachella Valley Archaeological Society. 3 84

PROJECT ARCHAEOLOGIST/REPORT WRITER
Frank J. Raslich, M.A.

Education
2016-
2010
2005
2019
2014
Ph.D. candidate, Michigan State University, East Lansing.

M.A., Anthropology, Michigan State University, East Lansing.

B.A., Anthropology, University of Michigan, Flint.

Grant and Research Proposal Writing for Archaeologists; Society for American Archaeology online seminar.

Bruker Industries Tracer S 1800 pXRF Training; presented by Dr. Bruce Kaiser, Bruker Scientific.

Professional Experience
2022-
2022
2014-2022
2008-2021
2019
2016-2018
2017-2018
2009-2017
2008-2014
2010-2013
2009-2011
Publications
2017
2013
Project Archaeologist/Report Writer, CRM TECH, Colton, California.

Archaeological Monitor, Agua Caliente Band of Cahuilla Indians, Palm Springs, California.

Board of Directors, Ziibiwing Center of Anishinabe Culture and Lifeways, Saginaw Chippewa Indian Tribe of Michigan.

Archaeological Consultant, Saginaw Chippewa Indian Tribe of Michigan.

Archaeologist, Sault Tribe of Chippewa Indians and Little Traverse Bay Band of Odawa Indians.

Adjunct Lecturer, Michigan State University, East Lansing.

Adjunct Lecturer, University of Michigan, Flint.

Teaching Assistant, Michigan State University, East Lansing.

Research Assistant, Intellectual Property Issues in Cultural Heritage, Simon Fraser University, British Columbia, Canada.

Research Assistant, Michigan State University, East Lansing.

Archaeologist/Crew Chief, Saginaw Chippewa Indian Tribe of Michigan.

Preliminary Results of a Handheld X -Ray Fluorescence (pXRF) Analysis on a Marble Head Sarcophagus Sculpture from the Collection of the Kresge Art Center, Michigan State University. Submitted to Jon M. Frey, Department of Art, Art History, and Design, Michigan State University, East Lansing.

Geochemical Analysis of the Dickenson Group of the Upper Peninsula, Michigan: A study of an Accreted Terrane of the Superior Province. Geological Society of America Abstracts with Programs 45:4(53).
3s'�

PROJECT ARCHAEOLOGIST
Michael D. Richards, M.A., Registered Professional Archaeologist Education
2002 M.A., Anthropology, California State University, Northridge (CSUN). 1986 B.A., Anthropology: University of California, Los Angeles (UCLA). 1982 A.A., Los Angeles Valley College, Los Angeles, California. 2015 Section 106 workshop.
2000 CSUN "Olmec" field excavation and lab analysis; La Venta, Mexico. 1999 Rock art recording, UCLA Extension; Little Lake, California. 1998 Rock art symposium, UCLA Extension.

Professional Experience
2018- Project Archaeologist/Paleontologist, CRM TECH, Colton, Calif. 2016-2018 Co -Principal Investigator/Archaeologist, LSA Associates Inc. 2012-2016 Co -Principal Investigator/Archaeologist, ICF International (Jones & Stokes). 2010-2012 Co -Principal Investigator/Archaeologist, various CRM firms (on call). 2007-2010 Principal Investigator/Field Director/Crew Chief, ASM Affiliates, Inc. 2004-2007 Project Manager/Co-Principal Investigator, ArchaeoPaleo Resource Management, Inc. 2003-2004 Staff Archaeologist/Crew Chief, SRI, Inc.
2000-2003 Project Archaeologist/Field Director, Ancient Enterprises (Clewlow, Jr.). 1999-2000 Staff Archaeologist/Lab Crew Chief, CSC/Edwards Air Force Base.

Memberships
Society for American Archaeology; Society for California Archaeology; Archaeological Institute of America; Conejo Open Space Trails Advisory Committee; Conejo Valley Historical Society.

PROJECT ARCHAEOLOGIST/NATIVE AMERICAN LIAISON
Nina Gallardo, B.A.

Education
2004 B.A., Anthropology/Law and Society, University of California, Riverside.

Professional Experience
2004- Project Archaeologist, CRM TECH, Riverside/Colton, California.

Cultural Resources Management Reports
Co-author of and contributor to numerous cultural resources management reports since 2004. 3 s'6

APPENDIX 2

NATIVE AMERICAN RESPONSES
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AGUA CALIENTE BAND OF CAHUILLA INDIANS

TRIBAL HISTORIC PRESERVATION
April 22, 2024
[VIA EMAIL TO:ngallardo &rmtech.us]

CRM TECH
Ms. Nina Gallardo
1016 E. Cooley Drive, Suite A/B
Colton, CA 92324
Re CRM Tech No. 4127
Dear Ms. Nina Gall ardo,
03-008-2024-006
The Agua Caliente Band of Cahuilla Indians (ACBCI) appreciates your efforts to include the Tribal Historic Preservation Office (THPO) in the CRM TECH No. 4127 project. The project area is not located within the boundaries of the ACBCI Reservation. However, it is within the Tribe's Traditional Use Area. For this reason, the ACBCI THPO requests the following:
*A cultural resources inventory of the project area by a qualified archaeologist prior to any development activities in this area.
*Copies of any cultural resource documentation (report and site records) generated in connection with this project.
*A copy of the records search with associated survey reports and site records from the information center.
*The presence of an approved Agua Caliente Native American Cultural Resource Monitor(s) during any ground disturbing activities (including archaeological testing and surveys). Should buried cultural deposits be encountered, the Monitor may request that destructive construction halt and the Monitor shall notify a Qualified Archaeologist (Secretary of the Interior's Standards and Guidelines) to investigate and, if necessary, prepare a mitigation plan for submission to the State Historic Preservation Officer and the Agua Caliente Tribal Historic Preservation Office. *We would like to participate in the survey.

Again, the Agua Caliente appreciates your interest in our cultural heritage. If you have questions or require additional information, please call me at (760) 423-3485. You may also email me at ACB CI-THPO [email protected].

Cordially,
5401 DINAH SNORE DRIVE,. PAL M SPRINGS. CA 92264
7ROidiftdI0MOU 1- 7nU;dAd/6d DA WWW.Ar:UACALILLNIC.NSN r,qV 388

AGUA CALIENTE BAND OF CAHUILLA INDIANS

TRIBAL HISTORIC PRESERVATION
Xitlaly Madrigal
Cultural Resources Analyst
Tribal Historic Preservation Office

AGUA CALIENTE BAND

OF CAHUILLA INDIANS
5401 DINAH SNORE DRIVE,. PAL M SPRINGS. CA 92264
1 7eO16RH/ntlOU 1- 7iO 4flI /6UDA WWW.Ar:UAC'ALILLNIC.NSN r,qV 21 389

CHAIRPERSON
Reginald Pagalno
Cnum ash

VK E -CHAIRPERSON
Bury MCQuIllen
Yo"avo Pam o, Yu 1'I,
Nom.k)P:i

SECRETARY
Sara Dulschke
Miwok

PARLIAMENTARIAN
Wayne Nelson
Luaeno
COmmis M1 ER
Isaac Batorquez
Ohbne-Costanoon

COMMISSIONER
Stanley Rodriguez
.Kum evaay
Cc .W Iss� ?N E6:

Lauren Bolden
Serrano

COMMISSIONER
Reid Mlianoylch
Co,huifro
COMMISSoN ER
Bennae Calac
Paurn a-Yukn a Band of
Lucei a indions
ExECUuTIVE SECRETAF"I
Raymond C.

Hitchcock
Miwok, Nisenan

NAHC HEADQUARTERS
1550 Harbor Boulevard
Suite 100
West Sacramento,
Caffomia 95191
(916) 373.3710
[email protected]
STATE OF CALIFORNIA Gavin Howson', Gov.mO(

NATIVE AMERICAN HERITAGE COMMISSION
May 6, 2024
Nina Gallardo

CRM TECH
Via Email to: naa
lardoxtcrmtec
,.us
Re: Proposed Rancho Mirage 2 Project, Riverside County
To Whom It May Concern:

A record search of the Native American Heritage Commission (NAHC) Sacred Lands File (SLF) was completed for the information you have submitted for the above referenced project. The results were negative. However, the absence of specific site information in the SLF does not indicate the absence of cultural resources in any project area. Other sources of cultural resources should also be contacted for information regording known and recorded sites.

Attached is a list of Native American tribes who may also hove knowledge of cultural resources In the project area. This list should provide a starting place in locating areas of potential adverse impact within the proposed project area. I suggest you contact all of those indicated; if they cannot supply information, they might recommend others with specific knowledge. By contacting all those fisted, your organization will be better able to respond to claims of failure to consult with the appropriate tribe. If a response has not been received within two weeks of notification, the Commission requests that you follow-up with a telephone call or email to ensure that the project information has been received.

If you receive notification of change of addresses and phone numbers from tribes, please notify me. With your assistance, we can assure that our fists contain current information.

If you have any questions or need additional information, please contact me al my email address: Andrew.Green&nahc.co.aov.

Sincerely,
Andrew Green
Cultural Resources Analyst
Attachment
Page I of I
22 390

Native American Heritage Commission
Native American Contact List
Riverside County
5/6/2024
Tribe Name Fed (F)
Non -Fed (N)
Contact Person Contact Address Phone # Fax # Email Address Cultural Counties Affiliation
Agua Caliente Band
of Cahuilla Indians
F
Lacy Padilla, Director of
Historic Preservation/THPO
5401 Dinah Shore Drive
Palm Springs, CA, 92264
(760) 333-5222
(760) 699-6919
[email protected]
Cahuilla
Imperial, Riverside, San
Bernardino, San Diego
Augustine Band of
Cahuilla Indians
F
Tribal Operations,
84-001 Avenue 54
Coachella, CA, 92236
(760) 398-4722
[email protected]
Cahuilla
Imperial, Riverside, San
Bernardino, San Diego
Cabazon Band of
Mission Indians
F
Doug Welmas, Chairperson
84-245 Indio Springs Parkway
Indio, CA, 92203
(760) 342-2593
(760) 347-7880
[email protected]
Cahuilla
Imperial, Riverside, San
Bernardino, San Diego
Cahuilla Band of
Indians
F
Anthony Madrigal, Tribal
Historic Preservation Officer
52701 CA Highway 371
Anza, CA, 92539
(951) 763-5549
[email protected]
Cahuilla
Imperial, Riverside, San
Bernardino, San Diego
Cahuilla Band of
Indians
F
BobbyRay Esaprza, Cultural
Director
52701 CA Highway 371
Anza, CA, 92539
(951) 763-5549
[email protected]
Cahuilla
Imperial, Riverside, San
Bernardino, San Diego
Cahuilla Band of
Indians
F
Erica Schenk, Chairperson
52701 CA Highway 371
Anza, CA, 92539
(951) 590-0942
(951) 763-2808
[email protected]
Cahuilla
Imperial, Riverside, San
Bernardino, San Diego
Los Coyotes Band of
Cahuilla and Cupeno
Indians
F
Ray Chapparosa,
Chairperson
P.O. Box 189
Warner Springs, CA, 92086-0189
(760) 782-0711
(760) 782-0712
Cahuilla
Imperial, Riverside, San
Bernardino, San Diego
Morongo Band of
Mission Indians
F
Ann Brierty, THPO
12700 Pumarra Road
Banning, CA, 92220
(951) 755-5259
(951) 572-6004
[email protected]
Cahuilla
Serrano
Imperial, Kern, Los Angeles,
Riverside, San Bernardino,
San Diego
Morongo Band of
Mission Indians
F
Robert Martin, Chairperson
12700 Pumarra Road
Banning, CA, 92220
(951) 755-5110
(951) 755-5177
[email protected]
Cahuilla
Serrano
Imperial, Kern, Los Angeles,
Riverside, San Bernardino,
San Diego
Quechan Tribe of the
Fort Yuma
Reservation
F
Jill McCormick, Historic
Preservation Officer
P.O. Box 1899
Yuma, AZ, 85366
(928) 261-0254
[email protected]
Quechan
Imperial, Kern, Los Angeles,
Riverside, San Bernardino,
San Diego
Quechan Tribe of the
Fort Yuma
Reservation
F
Manfred Scott, Acting
Chairman - Kw'ts'an Cultural
Committee
P.O. Box 1899
Yuma, AZ, 85366
(928) 210-8739
[email protected]
Quechan
Imperial, Kern, Los Angeles,
Riverside, San Bernardino,
San Diego
Quechan Tribe of the
Fort Yuma
Reservation
F
Jordan Joaquin, President,
Quechan Tribal Council
P.O.Box 1899
Yuma, AZ, 85366
(760) 919-3600
[email protected]
Quechan
Imperial, Kern, Los Angeles,
Riverside, San Bernardino,
San Diego
Ramona Band of
Cahuilla
F
John Gomez, Environmental
Coordinator
P. O. Box 391670
Anza, CA, 92539
(951) 763-4105
(951) 763-4325
[email protected]
Cahuilla
Imperial, Riverside, San
Bernardino, San Diego
Ramona Band of
Cahuilla
F
Joseph Hamilton,
Chairperson
P.O. Box 391670
Anza, CA, 92539
(951) 763-4105
(951) 763-4325
[email protected]
Cahuilla
Imperial, Riverside, San
Bernardino, San Diego
Santa Rosa Band of
Cahuilla Indians
F
Vanessa Minott, Tribal
Administrator
P.O. Box 391820
Anza, CA, 92539
(951) 659-2700
(951) 659-2228
[email protected]
Cahuilla
Imperial, Los Angeles,
Orange, Riverside, San
Bernardino, San Diego
Santa Rosa Band of
Cahuilla Indians
F
Steven Estrada, Tribal
Chairman
P.O. Box 391820
Anza, CA, 92539
(951) 659-2700
(951) 659-2228
[email protected]
Cahuilla
Imperial, Los Angeles,
Orange, Riverside, San
Bernardino, San Diego
Soboba Band of
Luiseno Indians
F
Isaiah Vivanco, Chairperson
P.O. Box 487
San Jacinto, CA, 92581
(951) 654-5544
(951) 654-4198
[email protected]
Cahuilla
Luiseno
Imperial, Los Angeles,
Orange, Riverside, San
Bernardino, San Diego
Soboba Band of
Luiseno Indians
F
Jessica Valdez, Cultural
Resource Specialist
P.O. Box 487
San Jacinto, CA, 92581
(951) 663-6261
(951) 654-4198
[email protected]
Cahuilla
Luiseno
Imperial, Los Angeles,
Orange, Riverside, San
Bernardino, San Diego
Soboba Band of
Luiseno Indians
F
Joseph Ontiveros, Tribal
Historic Preservation Officer
P.O. Box 487
San Jacinto, CA, 92581
(951) 663-5279
(951) 654-4198
[email protected]
Cahuilla
Luiseno
Imperial, Los Angeles,
Orange, Riverside, San
Bernardino, San Diego
361

Torres -Martinez
Desert Cahuilla
Indians
F
Mary Belardo, Cultural
Committee Vice Chair
P.O. Box 1160
Thermal, CA, 92274
(760) 397-0300
[email protected]
Cahuilla
Imperial, Riverside, San
Bernardino, San Diego
Torres -Martinez
Desert Cahuilla
Indians
F
Thomas Tortez, Chairperson
P.O. Box 1160
Thermal, CA, 92274
(760) 397-0300
(760) 397-8146
[email protected]
Cahuilla
Imperial, Riverside, San
Bernardino, San Diego
Torres -Martinez
Desert Cahuilla
Indians
F
Gary Resvaloso, TM MLD
P.O. Box 1160
Thermal, CA, 92274
(760) 777-0365
[email protected]
Cahuilla
Imperial, Riverside, San
Bernardino, San Diego
Torres -Martinez
Desert Cahuilla
Indians
F
Alesia Reed, Cultural
Committee Chairwoman
P.O. Box 1160
Thermal, CA, 92274
(760) 397-0300
[email protected]
Cahuilla
Imperial, Riverside, San
Bernardino, San Diego
Torres -Martinez
Desert Cahuilla
Indians
F
Abraham Becerra, Cultural
Coordinator
P.O. Box 1160
Thermal, CA, 92274
(760) 397-0300
[email protected]
Cahuilla
Imperial, Riverside, San
Bernardino, San Diego
This list is current only as of the date of this document. Distribution of this list does not relieve any person of statutory responsibility as defined in Section 7050.5 of the Health and Safety Code, Section 5097.94 of the Public Resource Section 509T98 of the Public Resources Code.

This list is only applicable for contacting local Native Americans with regard to cultural resources assessment for the proposed Rancho Mirage 2 Project, Riverside County. 24 Record: PROJ-2024-002329
Report Type: List of Tribes
Counties: Riverside
NAHC Group: All
392

Rancho Mirage Affordable Housing Family Apartments
Initial Study/Mitigated Negative Declaration
May 2025
Appendix D
Design -Phase Geotechnical Investigation Report
City of Rancho Mirage D
393

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DESIGN -PHASE GEOTECHNICAL INVESTIGATION REPORT

PROPOSED RANCHO MIRAGE APARTMENTS
APPROXIMATELY 5 ACRES SOUTH OF THE RANCHO MIRAGE DOG PARK A PORTION OF ASSESSOR'S PARCEL NO. 685-090-011

RANCHO MIRAGE, RIVERSIDE COUNTY, CALIFORNIA

NATIONAL CORE
July 25, 2024
J.N. 24-112
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PETRA

SOLID AS A ROCK
ENGINEERS + GEOLOGISTS + ENVIRONMENTAL SCIENTISTS
July 25, 2024
J.N. 24-112

NATIONAL CORE
430 E. State Street, Suite 100
Eagle, Idaho 83616
Attention: Ms. Taylor Libolt Varner
Subject: Design -Phase Geotechnical Investigation Report, Proposed Rancho Mirage Apartments, Approximately 5 Acres South of the Rancho Mirage Dog Park, a Portion of Assessor's Parcel No. 685-090-011, Rancho Mirage, Riverside County, California Dear Ms. Libolt Varner:

Petra Geosciences, Inc. (Petra) is submitting herewith our geotechnical investigation report for the proposed construction of approximately 150 apartments at the subject location in the city of Rancho Mirage.

The proposed improvements will also include utilities, paved parking, landscaping, and on -site stormwater retention. This work was performed in general accordance with the scope of services outlined in our Proposal No. 24-112P, dated January 17, 2024. This report presents the results of our field investigation, laboratory testing, and our engineering and geologic analysis, judgment, opinions, conclusions and recommendations pertaining to geotechnical design aspects of the proposed improvements.

It is a pleasure to be of service to you on this project. Should you have any questions regarding the contents of this report, or should you require additional information, please do not hesitate to contact us.

Respectfully submitted,
PETRA GEOSCIENCES, INC.
.711
Alan Pace
Senior Associate Geologist
Offices Strategically Positioned Throughout Southern California

DESERT REGION OFFICE
42-240 Green Way, Suite E, Palm Desert, CA 92211 395
T: 760.340.5303 F: 760.340.5096
For more information visit us online at www.oetra-inc.com

NATIONAL CORE
Rancho Mirage Apartments / Rancho Mirage
July 25, 2024
J.N. 24-112

TABLE OF CONTENTS
Page
PURPOSE AND SCOPE OF SERVICES 1
LOCATION AND SITE DESCRIPTION 2
PROPOSED IMPROVEMENTS 2
FIELD EXPLORATION AND TESTING 3
Subsurface Exploration 3
Laboratory Testing 3
Percolation Testing 4
FINDINGS 5
Regional Geologic Setting 5
Local Geology and Subsurface Soil Conditions 5
Groundwater 6
Faulting 6
Secondary Seismic Hazards 6
Seismically Induced Landsliding 6
Seismically Induced Flooding 6
Liquefaction and Seismically Induced Settlement 6
CONCLUSIONS AND RECOMMENDATIONS 9
General Feasibility 9
Earthwork and Grading 9
General Specifications 9
Geotechnical Observations and Testing 9
Demolition, Clearing and Grubbing 10
Unsuitable Soil Removals and Bottom Processing 10
Grading at Site Boundaries 11
Excavation Characteristics 11
Fi11 Placement 11
Imported Soils 11
Volumetric Changes - Bulking, Shrinkage and Subsidence 12 Temporary Excavations 12
Expansive Soil Conditions 12
PRELIMINARY FOUNDATION DESIGN CONSIDERATIONS 13
Seismic Design Parameters 13
Discussion 15
Foundation System 16
Allowable Soil Bearing Capacity, Anticipated Settlement and Lateral Resistance 16 Estimated Static Settlement 16
Seismically Induced Settlement 17
Lateral Resistance 17
Guidelines for Footings and Slabs on -Grade Design and Construction 17 Conventional Slabs on -Grade System 18
Post -Tensioned Slabs on -Grade System 20
Foundation Excavation Observations 23
General Corrosivity Screening 23
Post -Grading Considerations 24
Utility Trenches 24
Site Drainage 25
Bottomless Trench Drains 26
Retaining Walls 26
Active and At -Rest Earth Pressures 26
Earthquake Loads Retaining Walls 27
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396
SO110 AS A POCK

NATIONAL CORE
Rancho Mirage Apartments / Rancho Mirage
July 25, 2024
J.N. 24-112

TABLE OF CONTENTS
Page
Subdrainage 27
Waterproofing 28
Wa11 Backfill 28
Geotechnical Observation and Testing 28
Masonry Block Walls 28
Exterior Concrete Flatwork 29
General 29
Thickness and Joint Spacing 29
Reinforcement 30
Edge Beams (Optional) 30
Subgrade Preparation 30
Drainage 31
Tree Wells 31
Swimming Pool and Spa 31
Allowable Bearing and Settlement 31
Lateral Earth Pressures 32
Stability of Temporary Excavation 32
Temporary Access Ramps 32
Pool Bottom 32
Pool Decking 32
Plumbing Fixtures 33
ACCESS ROADS 33
Asphalt Pavement 33
PLAN REVIEW 34
REPORT LIMITATIONS 34
REFERENCES 36

ATTACHMENTS
FIGURES RW-1 through RW-3 — RETAINING WALL DETAILS
FIGURE 1 - SITE LOCATION MAP
FIGURE 2 - BORING LOCATION MAP

APPENDIX A - BORING LOGS

APPENDIX B - LABORATORY TEST PROCEDURES / LABORATORY DATA SUMMARY

APPENDIX C - SEISMIC HAZARD ANALYSIS

APPENDIX D - DRY SAND SETTLEMENT

APPENDIX E - PERCOLATION / INFILTRATION

APPENDIX F - STANDARD GRADING RECOMMENDATIONS/RETAINING WALLS PETRA
397
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DESIGN -PHASE GEOTECHNICAL INVESTIGATION REPORT

PROPOSED RANCHO MIRAGE APARTMENTS
APPROXIMATELY 5 ACRES SOUTH OF THE RANCHO MIRAGE DOG PARK A PORTION OF ASSESSOR'S PARCEL NO. 685-090-011

RANCHO MIRAGE, RIVERSIDE COUNTY, CALIFORNIA

PURPOSE AND SCOPE OF SERVICES
Petra Geosciences, Inc. (Petra) is presenting herein our design -phase geotechnical investigation report for an apartment buildings complex and various improvements that are currently proposed at the vacant site located in the city of Rancho Mirage, California. The improvements include the construction of a series of apartment buildings and associated utilities, paved parking, landscaping, and on -site stormwater retention.

The purposes of this investigation were to 1) obtain information regarding surface and subsurface geologic conditions within the area of the proposed construction, 2) evaluate the engineering properties of the onsite soil materials, and 3) provide conclusions and recommendations for design and construction of the proposed improvements. To accomplish these objectives, our scope of services included the following:

1. Reviewing of published and unpublished literature and maps pertaining to regional faulting, seismic hazards and soil and geologic conditions within and adjacent to the site that could influence the design of the proposed structural elements.

2. Reviewing of historical aerial photographs of the area of proposed construction.

3. Performing a subsurface investigation within the area of proposed construction. The investigation consisted of drilling 3 exploratory borings to depths of 20 to 66 feet using a hollow -stem drilling rig. Additionally, drilling 1 exploratory boring to 10 feet below ground surface using the hollow - stem auger drilling method and performing a falling -head percolation test in the borehole. The boring logs are presented in Appendix A and the percolation tests results and infiltration rate calculations are presented in Appendix E.

4. Logging and field -classifying soil materials encountered in each boring in accordance with the visual -manual procedures outlined in the Unified Soil Classification System and the American Society for Testing and Materials (ASTM) Procedure D 2488-90. All field activities were performed by or under the direct observation of a State of California Certified Engineering Geologist.

5. Collecting representative bulk and relatively undisturbed soil samples for laboratory analysis.

Undisturbed samples will be retrieved at 3- to 10 -foot depth intervals utilizing a 2.4 -inch inside diameter, modified -California split -spoon sampler. In addition, where granular soils were encountered within the saturated zone, these materials were selectively sampled using the Standard Penetration Test (SPT) method in accordance with ASTM Procedure D 1586-92.

6. Performing appropriate laboratory analysis on soil samples which included the following: in -situ and maximum dry density; in -situ and optimum moisture content; sieve analysis, remolded direct shear; collapse analysis; soluble sulfate and chloride content; general soil corrosivity (Sulfate, Chloride, pH and minimum resistivity).
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7. Engineering and geologic analyses of the field and laboratory data as they pertain to the proposed construction.

8. An evaluation of faulting and seismicity of the region, and the possible impact of regional seismicity on the proposed construction.

9. Preparation of this geotechnical report presenting the results of our evaluation and recommendations for the proposed development in general conformance with the 2022 California Building Code (2022 CBC) and in accordance with applicable state and local jurisdictional requirements.

LOCATION AND SITE DESCRIPTION
The area of study considered under the scope of this investigation consists of 5 acres located to the southeast of the Rancho Mirage Dog Park. The location of the site with respect to nearby roadways and other landmarks is shown on the Site Location Map, Figure 1. The subject site is vacant and is bordered on the north by vacant land and existing shopping center along Dinah Shore Drive, on the east by vacant land and Monterey Avenue, on the west by vacant land and Key Largo Avenue, and on the south by undeveloped vacant land. The topography is approximately flat and level, with approximately 10 feet of relief from the south end of the site to the north end. The subject site's natural landscaping consists of few grasses and light desert scrub with no trees.

PROPOSED IMPROVEMENTS
Petra understands that the site is to be developed into approximately 150 apartments. Additionally, the improvements will consist of utilities, paved parking, landscaping, and on -site storm water retention.

Neither grading plans nor specific details related to the proposed improvements were provided to Petra at the time this report was prepared. Based on the nearby development and the relatively flat topography of the site, Petra assumes that earthwork is generally limited to minor cuts and fills to establish finished grade elevations. It should be noted, however, that remedial grading (i.e., excavation and re -compaction of any existing undocumented fill soils that are present on the site and loose native soils) will entail deeper cuts from exiting grades as recommended in subsequent sections of this report. No extensive subterranean construction is anticipated.
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FIELD EXPLORATION AND TESTING
Subsurface Exploration
Our subsurface exploration was performed on June 7, 2024, and involved the following:

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• Drilling and sampling of two relatively shallow borings (B-2 and B-3) to depths of 20 feet below the existing ground surface and one deep boring (B-1) to a depth of 66 feet below the existing ground surface. All of the borings were drilled utilizing a truck -mounted, hollow -stem auger drill rig.
• Drilling one boring to a depth of 10 feet (Boring P-1) and performing a percolation test to observe infiltration characteristics of subsurface materials for stormwater retention design.

Earth materials encountered in each of the exploratory borings were field classified and logged in accordance with Unified Soil Classification System, USCS, procedures. In addition, our subsurface exploration included the collection of bulk and relatively undisturbed samples of the subsurface soils for laboratory testing purposes. Bulk samples consisted of selected earth materials obtained at various depth intervals from selected borings. Relatively undisturbed samples were collected using a 3 -inch, outside - diameter, modified California split -spoon soil sampler lined with 1 -inch -high brass or stainless -steel rings.

The modified sampler was driven with successive 30 -inch drops of a hydraulically operated 140 -pound automatic trip hammer. Blow counts for each 6 -inch driving increment were recorded on the field logs. The central portions of the driven core samples were placed in sealed containers and transported to our laboratory for testing. The approximate locations of the exploratory borings are shown on the attached Boring Location Map, Figure 2, and descriptive exploration logs are presented in Appendix A.

In addition to the above sampling method, Standard Penetration Tests (SPT's) were also performed at selected depth intervals in accordance with the American Society for Testing Materials (ASTM) Standard Procedure D 1586. This method consists of mechanically driving an unlined standard split -barrel sampler 18 inches into the soil with successive 30 -inch drops of the 140 -pound automatic trip hammer. Blow counts for each 6 -inch driving increment were recorded on the exploration logs. The number of blows required to drive the standard split -spoon sampler for the last 12 of the 18 inches was identified as the uncorrected standard penetration resistance (N). Disturbed soil samples from the unlined standard split -spoon samplers were placed in plastic bags and transported to our laboratory for testing.

Laboratory Testing
In order to evaluate the engineering properties of onsite soils, a number of laboratory tests were performed on selected samples considered representative of the materials encountered within the study area. These eGEOSCIENCES"`
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laboratory tests were performed shortly after completion of our field investigation and included determination of in -place dry density and moisture content, maximum dry density and optimum moisture content, sieve analysis, collapse potential, remolded shear strength, as well as chemical and electrical corrosivity potential (soluble sulfate and chloride content, pH, and minimum resistivity). A description of laboratory test methods is provided in the Laboratory Test Procedures section of this report (Appendix B).

Summaries of the test data are presented on the exploration logs (Appendix A) and in Appendix B of this report.

Percolation Testing
Percolation testing was conducted in Exploratory Boring P-1 in accordance with County of Riverside Department of Environmental Health (RCDEH) test procedures and the guidelines presented in Appendix VII of the County of Orange Technical Guidance Document for WQMPs. The Orange County Manual references the RCDEH percolation test methods as an acceptable method of obtaining site infiltration data.

The "percolation rates" determined in accordance with the RCDEH test procedures are based on both horizontal (lateral) and vertical percolation. Therefore, to consider vertical percolation only, the "percolation rates" were converted to a reasonable estimate of the "infiltration rate" using the Porchet Method presented in Appendix VII of the referenced County of Orange Technical Guidance Document.

Boring P-1 was converted to a percolation test hole following drilling by placing a two-inch (I.D.) perforated PVC pipe in the test hole. The annular space around the pipe was filled with open -graded gravel, approximately 3/4 -inch, within the annular space between the pipe and boring walls and a 3 -inch -thick layer of gravel below the pipe. The remainder of the annular space was backfilled with boring cuttings. Clean water was then added to the boring to pre-soak the adjacent soils prior to performing the percolation test.

The percolation test was conducted in eolian sand that exists from the near surface to below the base of the percolation tests. Boring P-1 was drilled to a total depth of approximately 10 feet. The test hole was filled with clean water to approximately 5 feet from the ground surface. The drop in water level was measured at 10 -minute intervals. From these readings, the percolation characteristics of the underlying eolian sand deposits was estimated. Percolation test results are presented in Appendix E and are summarized in Table 1.

We note that the calculated infiltration rate presented in this table has a factor of safety of 1 and the project engineer should use an appropriate factor of safety per project Specifications.

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TABLE 1
Unfactored Percolation Test Results
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Test No.

Soil Type'
(USCS)
Depth of
Hole
(Feet)
Measured 2
Percolation Rate
(Minutes/Inch)
7 Infiltration Rate (It) s
per Porchet Method
(Inches/Hour) (F.S — 1)
P-1
SP
10 0.57

12.0 1 Interbedded Strata — see Boring Logs, Appendix A 2 RCDEH Test Procedure
3 Minutes/inch converted to inches/hour per Porchet Method

FINDINGS
Regional Geologic Setting
The proposed development is located in the Coachella Valley, which is part of the Salton Trough geomorphic province of California. The Salton Trough geomorphic province encompasses the Coachella, Imperial and Mexicali Valleys, which extend from northeast of Palm Springs near San Gorgonio Pass to the Gulf of California. The geologic structure of the trough is a result of extensional forces within the earth's crust. The Coachella Valley is generally bounded by the San Jacinto and Santa Rosa Mountains on the west, the San Bernardino and the Little San Bernardino Mountains on the north, the Cottonwood Mountains and the Mecca Hills on the east, and the Salton Sea to the south. Alluvial (Streams), aeolian (wind-blown), and lacustrine (lake) sediments are the dominant geologic units of the Coachella Valley.

The watershed of the Coachella Valley empties into the Salton Sea at the lowest part of the basin. This basin was periodically filled with water to form the ancient Lake Cahuilla, depending on which side of its delta the Colorado River would drain. The sediments of the delta form a topographic high that separates the Salton basin, which is below sea level, from the Gulf of California (Sea of Cortez).

Local Geology and Subsurface Soil Conditions
In general, the soil materials underlying the site as encountered in our borings were noted to consist of very loose to very dense, poorly graded eolian sand to the maximum depth explored of 66 feet. The upper 3 to 4 feet of the soil was found to be dry and very loose to loose. Soils become medium dense to dense and finer grained with depth. The moisture content of these native soils is very low and on the order of less than 0.5 percent. Laboratory testing of relatively undisturbed samples of eolian sand yielded in -place dry densities ranging from 98 to 109 pounds per cubic foot.
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Groundwater
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Free groundwater was not encountered within any of the exploratory borings advanced onsite to the maximum depth explored of 66 feet below grades. According to a monitoring well located approximately

0.5 miles to the north, groundwater is located approximately 160 feet below the ground surface as of July 18, 2023 (CDWR Station 338086N1163878W001).

Faulting
The Coachella Valley is a seismically active area and numerous northwest -trending active faults have been documented within the area. The San Andreas fault zone is the most prominent fault within the Coachella Valley and is considered to be "active". An "active" fault is defined as a fault that has had displacement within the Holocene epoch, or last ±11,000 years. Based on our review, the site is not located within a Fault Hazard Zone (Bryant and Hart, 2007), as defined by the state of California in the Alquist-Priolo Earthquake Fault Zoning Act and no evidence for faulting was observed within the site during our study.

Secondary Seismic Hazards
Seismically Induced Landsliding
The site exhibits a generally flat topography, and no landslides exist within or near the site. Based on the topography across the site, the potential for landsliding is considered negligible.

Seismically Induced Flooding
The types of seismically induced flooding that are generally considered as potential hazards to a particular site normally include flooding due to a tsunami (seismic sea wave), a seiche, or failure of a major reservoir or other water retention structure upstream of the site. The Salton Sea is situated approximately 25 miles southeast of the site with an elevation approximately 500 feet lower than the subject site. In addition, no major reservoir is located near or upstream of the site. Therefore, the potential for seiche or inundation is considered negligible. Because of the inland location of the site, flooding due to a tsunami is also considered negligible at the site.

Liquefaction and Seismically Induced Settlement
Liquefaction
Liquefaction is a soil softening dynamic response, by which an increase in the excess pore water pressure results in partial to full loss of soil shear strength and post -liquefaction dissipation of this pore water pressure results in ground settlement shortly after the earthquake. In order for liquefaction to occur, the 0 GEOSCIENCES"'.

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following four factors are required: 1) saturated soil or soil situated below the groundwater table; 2) undrained loading (strong ground shaking), such as by earthquake; 3) contractive soil response during shear loading, which is often the case for a soil which is initially in a loose or uncompacted state; and 4) susceptible soil type; such as clean, uniformly graded sands, non -plastic silts, or gravels. SP117A (CGS, 2008) discusses preliminary screening methods sufficient to evaluate liquefaction potential without requiring a comprehensive liquefaction analysis; one of the considerations is the depth to groundwater.

Sites with groundwater depth of around 50 feet below ground surface and deeper (including historic high ground water, current conditions, and future expectations), are considered unlikely to experience liquefaction within the upper 50 feet of the soil profile. Due to a very deep ground water table at the subject property (+160 feet) the potential for liquefaction at this site is considered negligible.

Dry Sand
Dry sand settlement can occur during moderate and large earthquakes when loose, natural or fill sandy soils are densified and settle, often unevenly across a site. In order for dry sand settlement to occur, the following four factors are required: 1) Relatively dry soil or soil situated above the groundwater table; 2) undrained loading (strong ground shaking), such as by earthquake; 3) contractive soil response during shear loading, which is often the case for a soil which is initially in a loose or uncompacted state; and 4) susceptible soil type; such as clean, uniformly graded sands. Structures situated above seismically densifying dry sandy soils may experience settlement or tilting of superstructures, or both.

Seismically Induced Settlement Parameters
Assessment of liquefaction or dry sand settlement potential for a particular site requires knowledge of a number of regional as well as site -specific parameters, including the estimated design earthquake magnitude, and the associated probable peak horizontal ground acceleration at the site, subsurface stratigraphy and soil characteristics. Parameters such as estimated probable peak horizontal ground acceleration can readily be determined using published references, or by utilizing a commercially available computer program specifically designed to perform a probabilistic analysis. In contrast, stratigraphy and soil characteristics can only be accurately determined by means of a site -specific subsurface investigation combined with appropriate laboratory analysis of representative samples of onsite soils.

Seismically Induced 'Dry Sand' Settlement
Propagating earthquake waves induces shearing stresses and strains in soil materials during strong ground shaking. This process rearranges the structure of granular soils such that there is an increase in density, with a corresponding decrease in volume, which results in vertical settlement. Seismically induced settlement has been well documented in wet, sandy deposits undergoing liquefaction (see Tokimatsu and Seed, 1987) leGEOSCIENCES"'
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and in relatively dry sediments as well (Stewart et al, 1996). Specific methods to analyze potential wet and dry dynamic settlement are reported in Tokimatsu and Seed (1987), Pradel (1998), and Stewart et al. (2001; 2002). Most of the referenced papers focus on the seismic effects on dry, clean sands of a uniform grain size, though several reports extend the literature to fine-grained soils (Stewart et al., 2001 & 2002). State guidelines for evaluating dynamic settlement are provided in the California Geological Survey Special Publication 117A (CGS, 2008).

To evaluate the potential for earthquake -induced dry sand settlement at the site and its impact on the proposed improvements, we performed a settlement analysis of the data from our 66 feet deep boring B-1 using LiqSVs program (Geologismiki, Version 2.3.2.11). LiqSVs is a software that evaluates liquefaction potential and calculates the settlement of soil deposits due to seismic loads. For the purpose of dry sand settlement analyses, we considered a design groundwater level at a depth of 160 feet below the existing ground surface, peak ground acceleration for maximum considered earthquake (PGAM) in the site vicinity to be approximately 0.868g, and a predominant earthquake magnitude of 7.49 Mw.

The results of our analysis indicate that the loose and medium dense poorly graded eolian sand encountered below the ground surface to the depth of approximately 10 feet in our borings appear to be prone to dry sand settlement during seismic shaking. Assuming that the upper 4 feet of soil will be replaced with an engineered fill soil not susceptible to dynamic settlement, we estimate that total dynamic settlement up to about 1'/z to 2 -inches is possible at the ground surface due to dry sand settlement from the MCE level earthquake. In our opinion, differential dry sand settlement of up to about 1'/2 -inch over a horizontal distance of approximately 100 feet may occur across the proposed improvements at the ground surface. A summary of our dry sand settlement analysis is presented in Appendix D. The estimated dry sand settlement should be considered during the structural design of the foundation system of the proposed improvements.

It should be noted that in the literature, prediction of the seismic settlement for unsaturated sandy soils, referred to as 'dry sand' settlement, is based on observation of performance of 5 sites that were comprised of clean sands, i.e. sands with 5 percent fines or less. However, the shallow site soils, above the assumed historic high groundwater level, are comprised of sands with substantial amounts of fines. The presence of fines influences (reduces) the settlement potential under a seismic event. To overcome this, the measured resistance parameters of soils with fines are first converted to that of clean sand values and then are used in the predictive routines. This is an indirect approach and, therefore, lacks the performance -based verification requirements. In addition, sandy deposits, especially within vadose zones, contain certain amount of pore water that, because of surface tension properties of water molecules, create tensile intra-particle forces, albeit, very weak, that are expected to reduce the particle rearrangement tendencies of sandy deposits during leGEOSCIENCES"`
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ground shaking. Further, sometimes the 'dry sand' seismic settlement calculation results are multiplied by factor of 2 to account for bidirectional nature of seismic waves propagations. That is, the investigators are provided with an optional factor of 2 to multiply the results of their seismic 'dry sand' calculations. It is our professional opinion that for the reasons cited herein dry sand settlement calculations are less reliable compared to that of the liquefaction settlement. It is perhaps for these and potentially other reasons that some review agencies do not require 'dry sand' settlement calculations as a part of their approval process.

CONCLUSIONS AND RECOMMENDATIONS
General Feasibility
Although the detailed development plans are not fully available, from a soils engineering and engineering geologic point of view and based on our current knowledge of the project, the subject property is considered suitable for the proposed development. It is our opinion that the proposed construction will not adversely affect the geologic stability of adjoining properties in an adverse manner provided grading and construction are performed in accordance with current standards of practice, all applicable grading ordinances and the recommendations presented in this report.

Earthwork and Grading
General Specifications
All earthwork and grading should be performed in accordance with all applicable requirements of the grading and excavation codes of the County of Riverside, and in compliance with all applicable provisions of the 2022 California Building Code (2022 CBC). Grading should also be performed in accordance with the recommendations provided in this report.

Geotechnical Observations and Testing
Prior to the start of earthwork, a meeting should be held at the site with the owner's representative, contractor and geotechnical consultant to discuss the work schedule and geotechnical aspects of the grading.

Earthwork, which in this instance will generally entail removal and re -compaction of the near surface soils, should be accomplished under full-time observation and testing by the geotec finical consultant. A representative of the project geotechnical consultant should be present onsite during all earthwork operations to document placement and compaction of fills, as well as to document compliance with the other recommendations presented herein.

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Demolition, Clearing and Grubbing
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Following any demolition, clearing operations should also include the removal of any remaining trash, debris, vegetation and similar deleterious materials including the root balls from any trees. Any cavities or excavations created upon removal of any unknown subsurface structures or inclusions should be cleared of loose soil, shaped to provide access for backfilling and compaction equipment and then backfilled with engineered fill. Note that buried deleterious materials may be encountered within the site (i.e., buried organics or debris) due to the past site usage and may need to be removed by hand (i.e., root pickers), during grading operations.

The project geoteclmical consultant should provide periodic observation and testing services during final clearing and grubbing operations to document compliance with the above recommendations. In addition, should unusual or adverse soil conditions or buried structures be encountered during grading that are not described herein, these conditions should be brought to the immediate attention of the project geoteclmical consultant for corrective recommendations.

Unsuitable Soil Removals and Bottom Processing
Any existing undocumented fill and near surface native soils are considered unsuitable for support of proposed structures and should be removed to underlying competent alluvial materials as approved by the project geotechnical consultant. As such, the estimated depth of removal is recommended to be approximately 4 feet below the existing ground surface, or 3 feet below the bottom of the deepest footing, whichever is deeper. Consideration should be given to locally deepening the excavation at the location of tree roots, any underground structures, or proposed subterranean features (if any), including swimming pools if proposed, in order to provide a uniform depth of compacted fill in all areas. Soil removals could be locally deeper depending upon the actual exposed conditions encountered during grading. At a minimum, the over -excavation should extend a distance beyond the perimeter of the supported structure equal to the depth of the over -excavation. The actual depths and horizontal limits of removals and over -excavations should be evaluated upon availability of the site grading plan and during grading on the basis of observations and testing performed by the project geotechnical consultant. Excavated soils, if found free of deleterious materials, are considered acceptable for use as compacted fill.

Prior to placing engineered fill, the exposed bottom surfaces in the removal areas should be approved by a representative of project geotechnical consultant. The exposed bottom(s) should be scarified to a minimum depth of 12 inches, moisture -conditioned or air-dried to achieve approximately two percent above optimum moisture content and then compacted with a heavy construction equipment prior to placement of fill. The 0 GEOSCIENCES"'.

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minimum compaction of the upper 12 inches of the removal bottom should meet or exceed 90 percent relative compaction. The laboratory maximum dry density, the standard for determining relative compaction, and optimum moisture content for each change in soil type should be determined in accordance with Test Method ASTM D 1557.

Grading at Site Boundaries
Average remedial removals wit Tin the building pad areas, extending horizontally beyond the limits of the proposed structures a distance equal to the depth of the overexcavation, are anticipated to be on the order of 4 feet below the existing ground surface, although locally deeper over -excavation is possible. A vertical cut at the perimeter of any overexcavation area along the property lines is not expected to remain stable. As such, vertical cuts immediately adjacent to existing structures (if any) are not acceptable from geotechnical standpoint. Specific recommendations for protection of any existing structures or improvements adjacent to the recommended overexcavation, either interior or at the perimeter of the site can be provided following review of site development plans. Recommendations may include shoring and slot -cutting for areas adjacent to property boundaries and underpinning, or other methods intended to prevent settlement or distress to existing improvements.

Excavation Characteristics
Based on the observed soil types in our borings, shallow excavation of soils within the site are expected to be readily excavatable with conventional earthmoving equipment.

Fill Placement
A11 fill materials should be placed in approximately 6- to 8 -inch -thick loose lifts, watered or air-dried as necessary to achieve a minimum moisture content at least 2 percent above the optimum moisture condition, and then compacted in -place to a minimum relative compaction of 90 percent. The laboratory maximum dry density and optimum moisture content for each change in soil type should be determined in accordance with ASTM D 1557.

Imported Soils
If imported soils are required to complete the planned grading, these soils should consist of clean materials devoid of rock exceeding a maximum dimension of 4 inches, organics, trash and other deleterious materials.

To avoid making revisions to the foundation design, imported soils should also be granular and exhibit a very low expansion potential (Expansion Index 0-20). Prospective import soils should be observed at the source, tested and approved by the geotechnical consultant prior to importing the soils to the site. It is PETRA
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recommended that the project environmental consultant should also be notified so that they can confirm the suitability of the proposed import material from an environmental standpoint.

Volumetric Changes - Bulking, Shrinkage and Subsidence
An average shrinkage factor estimated at 10 to 15 percent is anticipated when excavated on -site soils are replaced as properly compacted fill. A subsidence, estimated at 0.15 to 0.25 feet may also occur when exposed bottom surfaces in removal areas are scarified and re -compacted as recommended herein. These estimates of shrinkage and subsidence are intended for use by project planners in estimating earthwork quantities and should not be considered absolute values. Contingencies should be made for balancing earthwork quantities based on actual shrinkage and subsidence that will occur during grading.

Temporary Excavations
Temporary excavations up to a depth of up to roughly four feet below existing grades may be required to accomplish the recommended over -excavation of existing soils. Based on the physical properties of the onsite soils, any temporary excavations exceeding 4 feet in height should be cut back to an inclination of

1.5:1 (h:v) or flatter for the duration of the over -excavation of unsuitable soil material and replacement as compacted fill, as well as placement of underground utilities. During remedial grading the estimated 1.5:1 (h:v) recommendation may possibly be flattened or steepened, depending on conditions observed by a representative of the project geotechnical consultant. Other factors which should be considered with respect to the stability of the temporary slopes include construction traffic and/or storage of materials on or near the tops of the slopes, construction scheduling, presence of nearby walls or structures adjacent to the excavation and weather conditions at the time of construction. Applicable requirements of the California Construction and General Industry Safety Orders, the Occupational Safety and Health Act, OSHA, of 1970 and the Construction Safety Act should also be followed.

Expansive Soil Conditions
Based on available data, including the non -plastic, granular nature of the soils encountered in the subsurface exploration and the Expansion Index equal to zero in the tested representative sample, near -surface soils are considered Very Low in expansion potential (Expansion Index less than 20). Additional sampling and testing should be performed during site grading for determining actual expansion potential of the supporting building pad soils.
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PRELIMINARY FOUNDATION DESIGN CONSIDERATIONS
Seismic Design Parameters
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Earthquake loads on earthen structures and buildings are a function of ground acceleration which may be determined from the site -specific ground motion analysis. Alternatively, a design response spectrum can be developed for certain sites based on the code guidelines. To provide the design team with the parameters necessary to construct the design acceleration response spectrum for this project, we used two computer applications. Specifically, the first computer application, which was jointly developed by Structural Engineering Association of California (SEAOC) and California's Office of Statewide Health Planning and Development (OSHPD), the SEA/OSHPD Seismic Design Maps Tool website, https://seismicmaps.org , is used to calculate the ground motion parameters. The second computer application, the United Stated Geological Survey (USGS) Unified Hazard Tool website, https://earthquake.usgs.gov/hazards/interactive/ , is used to estimate the earthquake magnitude and the distance to surface projection of the fault. The results obtained from these websites are presented in Appendix C.

To run the above computer applications, site latitude and longitude, seismic risk category and knowledge of site class are required. The site class definition depends on the direct measurement of certain soil properties and the ASCE 7-16 recommended procedure for calculating the average shear wave velocity within the upper 30 meters (approximately 100 feet) of site soils. Several methods exist to determine the shear wave velocity, including correlation with SPT blow counts. Based on the blow counts obtained in boring B-1 (including converting California Modified Sampler blow counts to SPT after Burmister (1948)) and Petra's knowledge of site geologic conditions, Site Class D (D — Stiff Soil as per the SEA/OSHPD software) has been assigned to the subject site.

Petra has assumed that the proposed structures should be categorized as Risk Category II pursuant to 2022 CBC Table 1604.5. If the specifics of the proposed project warrant a different Risk Category, the members of the design team responsible for this determination may assign the appropriate Risk Category. Seismic design parameters provided below are not impacted by the assumed Risk Category.

The following table, Table 2, provides parameters required to construct the seismic response coefficient, Cs, curve based on ASCE 7-16, Article 12.8 guidelines. A printout of the computer output is attached in Appendix C. The results of conversion of blow count data to small -strain shear wave velocity are also provided in Appendix C.
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TABLE 2
Seismic Design Parameters
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Ground Motion Parameters
Specific Reference
Parameter
Value
Unit
Site Latitude (North)
-

33.796486
°
Site Longitude (West)
-
-116.394338
°
Site Class Definition
Section 1613.2.2 (1), Chapter 20 (2)
D -Stiff (4)
-
Assumed Risk Category
Table 1604A.5 (1>
II
-
Ma, - Earthquake Magnitude
USGS Unified Hazard Tool (3)

7.49 (3)
-
R — Distance to Surface Projection of Fault
USGS Unified Hazard Tool (3)

6.61 (3)
km
Ss - Mapped Spectral Response Acceleration
Short Period (0.2 second)
Figure 1613.2.1(1) (1)

1.819 (4)
g
Si - Mapped Spectral Response Acceleration
Long Period (1.0 second)
Figure 1613.2.1(2) 0)

0.757 (4)
g
Fa — Short Period (0.2 second) Site Coefficient
Table 1613A.2.3(1)(1)

1.0 (4)
-
Fa — Long Period (1.0 second) Site Coefficient
Table 1613A.2.3(2) (1)
Null (4)
-
SMS — MCER Spectral Response Acceleration Parameter
Adjusted for Site Class Effect (0.2 second)
Equation 16-36 (1)

1.819 (4)
g
SMi - MCER Spectral Response Acceleration Parameter
Adjusted for Site Class Effect (1.0 second)
Equation 16-37 (l)
Null (4)
g
SDs - Design Spectral Response Acceleration at 0.2-s
Equation 16-38 (1)

1.213 (4)
g
SDI - Design Spectral Response Acceleration at 1-s
Equation 16-39 (1)
Null (4)
g
To = 0.2 SDI/ SDs
Section 11.4.6 (2)
Null
s
Ts= SDI/ SDs
Section 11.4.6 (2)
Null
s
TL - Long Period Transition Period
Figure 22-14 (2)
8 (4)
s
PGA - Peak Ground Acceleration at MCE0 (`)
Figure 22-9 (2)

0.789 (4)
g
FPGA - Site Coefficient Adjusted for Site Class Effect (2) Table 11.8-1 (2)

1.1 (4)
-
PGAM —Peak Ground Acceleration (2)
Adusted for Site Class Effect
Equation 11.8-1 (2)

0.868 (4)
g
Design PGA (2/3 PGAM) - Slope Stability (t)
Similar to Eqs. 16-38 & 16-39 (2)

0.58 g
Design PGA z (0.4 SDs) — Short Retaining Walls (I)
Equation 11.4-5 (2)

0.49 g
CRs - Short Period Risk Coefficient
Figure 22-18A (2)

0.893 (4)
-
CRI - Long Period Risk Coefficient
Figure 22-19A (2)

0.879 (4)
-
SDC - Seismic Design Category (§)
Section 1613.2.5 (1)
Null (4)
-
References:
(I) California Building Code (CBC), 2022, California Code of Regulations, Title 24, Part 2, Volume I and II. (2) American Society of Civil Engineers/Structural Engineering Institute (ASCE/SEI), 2016, Minimum Design Loads and Associated Criteria for Buildings and Other Structures, Standards 7-16. (3) USGS Unified Hazard Tool - https://earthquake.usgs.gov/hazards/interactive/ (4) SEUOSHPD Seismic Design Map Application — https://seismicmaps.org Related References:

Federal Emergency Management Agency (FEMA), 2015, NEHERP (National Earthquake Hazards Reduction Program) Recommended Seismic Provision for New Building and Other Structures (FEMA P-1050).

Notes:
* PGA Calculated at the MCE return period of 2475 years (2 percent chance of exceedance in 50 years). t PGA Calculated at the Design Level of 2/3 of MCE; approximately equivalent to a return period of 475 years (10 percent chance of exceedance in 50 years).
$ PGA Calculated for short, stubby retaining walls with an infinitesimal (zero) fundamental period. § The designation provided herein may be superseded by the structural engineer in accordance with Section 1613.2.5.1, if an 3licable. • GEOSCIENCES«s
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Discussion
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General
Owing to the characteristics of the subsurface soils, as defined by Site Class D -Stiff Soil designation, and proximity of the site to the sources of major ground shaking, the site is expected to experience strong ground shaking during its anticipated life span. Under these circumstances, where the code -specified design response spectrum may not adequately characterize site response, the 2022 CBC typically requires a site - specific seismic response analysis to be performed. This requirement is signified/identified by the "null" values that are output using SEA/OSHPD software in determination of short period, but mostly, in determination of long period seismic parameters, see Table 2.

For conditions where a "null" value is reported for the site, a variety of design approaches are permitted by 2022 CBC and ASCE 7-16 in lieu of a site -specific seismic hazard analysis. For any specific site, these alternative design approaches, which include Equivalent Lateral Force (ELF) procedure, Modal Response Spectrum Analysis (MRSA) procedure, Linear Response History Analysis (LRHA) procedure and Simplified Design procedure, among other methods, are expected to provide results that may or may not be more economical than those that are obtained if a site -specific seismic hazards analysis is performed. These design approaches and their limitations should be evaluated by the project structural engineer.

Seismic Design Category
Please note that the Seismic Design Category, SDC, is also designated as "null" in Table 2. For Risk Category is I, II, or III structures, where the mapped spectral response acceleration parameter at 1— second period, Si, is greater than or equal to 0.75, the 2022 CBC, Section 1613.2.5 requires the assignment to Seismic Design Category E.

Equivalent Lateral Force Method
Should the Equivalent Lateral Force (ELF) method be used for seismic design of structural elements, the value of Constant Velocity Domain Transition Period, TS, is estimated to be 0.71 seconds and the value of Long Period Transition Period, TL, is provided in Table 2 for construction of Seismic Response Coefficient — Period (Cs -T) curve that is used in the ELF procedure.

As stated herein, the subject site is considered to be within a Site Class D -Stiff Soil. A site -specific ground motion hazard analysis is not required for structures on Site Class D -Stiff Soil with S1 > 0.2 provided that the Seismic Response Coefficient, Cs, is determined in accordance with ASCE 7-16, Article 12.8 and structural design is performed in accordance with Equivalent Lateral Force (ELF) procedure. eGEOSCIENCES"F
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Foundation System
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In consideration of the existing surficial soils and the recommended remedial grading herein, conventional shallow foundations, consisting of isolated column footings interconnected with tie beams and continuous footings, may be used for support of the proposed structures. Structural foundation loads are currently unknown but are assumed to be typical for two-story light -framed construction.

Eccentrically loaded footings should be avoided if possible. In the event that the design requires eccentric loading, the design should consider the effective footing dimensions rather than actual dimensions. Pad footings located closer than 2 x B (where B is the footing width) to an adjacent footing should be designed as a single footing. Allowable bearing capacity for square footings apply as long as L/B is less than 5 (where L is the footing length).

Allowable Soil Bearing Capacity, Anticipated Settlement and Lateral Resistance Pad Footings
Based on the test results (ultimate friction angle of 26.4 degrees and negligible cohesion), an allowable soil bearing capacity of 2,000 pounds per square foot, including dead and live loads, may be utilized for design of 24 -inch -square pad footings that are a part of the slab system and embedded a minimum of 12 inches below the lowest adjacent compacted final grade. This value may be increased by 20 percent for each foot of embedment and by 10 percent for each additional foot of width, to a maximum value of 3,000 pounds per square foot. The recommended allowable bearing value includes both dead and live loads and may be increased by one-third for short duration wind and seismic forces.

Continuous Footings
An allowable soil bearing capacity of 1,500 pounds per square foot may be utilized for design of continuous footings founded at a minimum depth of 18 inches below the lowest adjacent fmal grade. This value may be increased by 20 percent for each additional foot of depth and by 10 percent for each additional foot of width, to a maximum value of 3,000 pounds per square foot. The recommended allowable bearing value includes both dead and live loads and may be increased by one-third for short duration wind and seismic forces.

Estimated Static Settlement
Based on the allowable bearing values provided above, total static settlement of the footings under the anticipated loads is expected to be on the order of 1 inch. Differential settlement is expected to be less than 3/4 inch over a horizontal span of 30 feet. The majority of settlement is likely to take place as footing loads are applied or shortly thereafter.
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Seismically Induced Settlement
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As previously noted, if remedial grading removes and replaces the upper 4 feet of existing soils as compacted fill, the total seismic settlement is estimated at approximately 2 inches. Differential seismic settlement is estimated to be around 1 '/2 inches over a span of 100 feet.

Lateral Resistance
A passive earth pressure of 250 pounds per square foot per foot of depth, to a maximum value of 2,500 pounds per square foot, may be used to determine lateral bearing resistance for footings. In addition, a coefficient of friction of 0.30 times the dead load forces may be used between concrete and the supporting soils to determine lateral sliding resistance. The above values may be increased by one-third when designing for transient wind or seismic forces. It should be noted that the above values are based on the condition where footings are cast in direct contact with compacted fill or competent native soils. In cases where the footing sides are formed, all backfill placed against the footings upon removal of forms should be compacted to at least 90 percent of the applicable maximum dry density.

Guidelines for Footings and Slabs on -Grade Design and Construction Based on the sandy nature of the material encountered in the borings and Petra's experience in the area, the site soils have expansive indices less than 20. As indicated in Section 1803.5.3 of 2022 California Building Code (2022 CBC), these soils are considered non -expansive and, as such, the design of slabs on -grade is considered to be exempt from the procedures outlined in Sections 1808.6.2 of the 2022 CBC and may be performed using any method deemed rational and appropriate by the project structural engineer. However, the following minimum recommendations are presented herein for conditions where the project design team may require geotechnical engineering guidelines for design and construction of footings and slabs on -grade the project site.

The design and construction guidelines that follow are based on the above soil conditions and may be considered for reducing the effects of variability in fabric, composition and, therefore, the detrimental behavior of the site soils such as excessive short- and long-term total and differential heave or settlement. These guidelines have been developed on the basis of the previous experience of this firm on projects with similar soil conditions. Although construction performed in accordance with these guidelines has been found to reduce post -construction movement and/or distress, they generally do not positively eliminate all potential effects of variability in soils characteristics and future heave or settlement. l GEOSCIENCES""
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It should also be noted that the suggestions for dimension and reinforcement provided herein are performance -based and intended only as preliminary guidelines to achieve adequate performance under the anticipated soil conditions. However, they should not be construed as replacement for structural engineering analyses, experience and judgment. The project structural engineer, architect and/or civil engineer should make appropriate adjustments to slab and footing dimensions, and reinforcement type, size and spacing to account for internal concrete forces (e.g., thermal, shrinkage and expansion), as well as external forces (e.g., applied loads) as deemed necessary. Consideration should also be given to minimum design criteria as dictated by local building code requirements.

Conventional Slabs on -Grade System
Considering an expansion index of less than 20, we recommend that footings and floor slabs be designed and constructed in accordance with the following minimum criteria.

Footings

1. Exterior continuous footings supporting one- and two-story structures should be founded at a minimum depth of 18 inches below the lowest adjacent final grade, respectively. Interior continuous footings may be founded at a minimum depth of 12 inches below the top of the adjacent finish floor slabs.

2. In accordance with Table 1809.7 of 2022 CBC for light -frame construction, all continuous footings should have minimum widths of 12 inches for one- and two-story structures. We recommend all continuous footings should be reinforced with a minimum of two No. 4 bars, one top and one bottom.

3. A minimum 12 -inch -wide grade beam founded at the same depth as adjacent footings should be provided across garage entrances or similar openings (such as large doors or bay windows). The grade beam should be reinforced in a similar manner as provided above.

4. Interior isolated pad footings, if required, should be a minimum of 24 inches square and founded at a minimum depth of 12 inches below the bottoms of the adjacent floor slabs for one- and two-story structures. Pad footings should be reinforced with No. 4 bars spaced a maximum of 18 inches on centers, both ways, placed near the bottoms of the footings.

5. Exterior isolated pad footings intended for support of roof overhangs such as second -story decks, patio covers, and similar construction should be a minimum of 24 inches square and founded at a minimum depth of 18 inches below the lowest adjacent final grade. The pad footings should be reinforced with No. 4 bars spaced a maximum of 18 inches on centers, both ways, placed near the bottoms of the footings. Exterior isolated pad footings may need to be connected to adjacent pad and/or continuous footings via tie beams at the discretion of the project structural engineer.

6. The minimum footing dimensions and reinforcement recommended herein may be modified (increased or decreased subject to the constraints of Chapter 18 of the 2022 CBC) by the structural engineer responsible for foundation design based on calculations, engineering experience and judgment.

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Building Floor Slabs
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1. Concrete floor slabs should be a minimum of 4 inches thick and reinforced with No. 3 bars spaced a maximum of 24 inches on centers, both ways. Alternatively, the structural engineer may recommend the use of prefabricated welded wire mesh for slab reinforcement. For this condition, the welded wire mesh should be of sheet type (not rolled) and should consist of 6x6/W2.9xW2.9 (per the Wire Reinforcement Institute, WRI, designation) or stronger. All slab reinforcement should be supported on concrete chairs or brick to ensure the desired placement near mid -depth. Care should be exercised to prevent warping of the welded wire mesh between the chairs in order to ensure its placement at the desired mid -slab position.

Slab dimension, reinforcement type, size and spacing need to account for internal concrete forces (e.g., thermal, shrinkage and expansion) as well as external forces (e.g., applied loads), as deemed necessary.

Consideration should also be given to using a control joint spacing on the order of 2 feet in each direction for each inch of slab thickness.

It should be noted that some of the non -climatic site parameters, which may impact slabs on - grade performance, are not known at this time, as it is the case for many projects at the design stage. Some of these site parameters include unsaturated soils diffusion conditions pre- and post -construction (e.g., casting the slabs at the end of long, dry or wet periods, maintenance during long, dry and wet periods, etc.), landscaping, alterations in site surface gradient, irrigation, trees, etc. While the effects of any or a combination of these parameters on slab performance cannot be accurately predicted, maintaining moisture content equilibrium within the soils mass and planting trees at a distance greater than half of their mature height away from the edge of foundation may reduce the potential for the adverse impact of these site parameters on slabs on -grade performance.

2. Living area concrete floor slabs and areas to receive moisture sensitive floor covering should be underlain with a moisture vapor retarder consisting of a minimum 10 -mil -thick polyethylene or polyolefin membrane that meets the minimum requirements of ASTM E96 and ASTM E1745 for vapor retarders (such as Husky Yellow Guard®, Stego® Wrap, or equivalent). A11 laps within the membrane should be sealed, and at least 2 inches of clean sand should be placed over the membrane to promote uniform curing of the concrete.

In general, to reduce the potential for punctures, the membrane should be placed on a pad surface that has been graded smooth without any sharp protrusions. If a smooth surface cannot be achieved by grading, consideration should be given to lowering the pad finished grade an additional inch and then placing a 1 -inch -thick leveling course of sand across the pad surface prior to the placement of the membrane.. Foot traffic on the membrane should be reduced to a minimum. Additional steps would also need to be taken to prevent puncturing of the vapor retarder during concrete placement.

To comply with Section 1907.1.1 of the 2022 CBC, the living area concrete floor slab should also be underlain with capillary break consisting of a minimum of 4 inches of gravel or crushed stone containing not more than 10 percent of material that passes through a No. 4 sieve. The capillary break should be placed below the 10 -mil moisture vapor retarder and may be considered as the structural fill recommended above.

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At the present time, some slab designers, geotechnical professionals and concrete experts view the sand layer below the slab (blotting sand) as a place for entrapment of excess moisture that could adversely impact moisture -sensitive floor coverings. As a preventive measure, the potential for moisture intrusion into the concrete slab could be reduced if the concrete is placed directly on the vapor retarder. However, if this sand layer is omitted, appropriate curing methods must be implemented to ensure that the concrete slab cures uniformly. A qualified materials engineer or contractor with experience in slab design, construction, and curing should provide recommendations for alternative methods of curing and supervise the construction process to ensure uniform slab curing. Additional steps would also need to be taken to prevent puncturing of the vapor retarder during concrete placement.

3. Garage floor slabs should be a minimum 4 inches thick and reinforced in a similar manner as living area floor slabs. Garage slabs should also be poured separately from adjacent wall footings with a positive separation maintained using 3/4 -inch -minimum felt expansion joint material. To control the propagation of shrinkage cracks, garage floor slabs should be quartered with weakened plane joints.

Consideration should be given to placement of a moisture vapor retarder below the garage slab, similar to that provided in Item 2 above, should the garage slab be overlain with moisture sensitive floor covering.

4. Presaturation of the subgrade below floor slabs will not be required; however, prior to placing concrete, the subgrade below all dwelling and garage floor slab areas should be thoroughly moistened to achieve a moisture content that is at least equal to or slightly greater than optimum moisture content. This moisture content should penetrate to a minimum depth of 12 inches below the bottoms of the slabs.

5. The minimum dimensions and reinforcement recommended herein for building floor slabs may be modified (increased or decreased subject to the constraints of Chapter 18 of the 2022 CBC) by the structural engineer responsible for foundation design based on calculations, engineering experience and judgment.

Post -Tensioned Slabs on -Grade System
In consideration of the expansion index of less than 20, as predominantly exhibited by onsite soils, any rational and appropriate procedure may be chosen by the project structural engineer for the design of post - tensioned slabs on -grade. Should the design engineer choose to follow the latest Code -adopted edition of the procedure published by the Post -Tensioning Institute (PTI DC 10.5), the following minimum design criteria are provided Table 3, below.
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TABLE 3
Presumptive Post -Tensioned Slab on -Grade Design Parameters for PTI Procedure , Soil Information
Approximate Depth of Constant Suction, feet
9 Approximate Soil Suction, pF

3.9 Inferred Thornthwaite Index:
-20
Average Edge Moisture Variation Distance, em in feet:

Center Lift
Edge Lift

9.0 4.7
Anticipated Swell, yin in inches:

Center Lift
Edge Lift

0.25 0.45
Modulus of Subgrade Reaction
The modulus of subgrade reaction for design of load bearing elements depends on the size of the element and soil -structure interaction. However, as a first level of approximation, this value may be assumed to be 125 pounds per cubic inch.

Minimum Design Recommendations
The soil values provided above may be utilized by the project structural engineer to design post -tensioned slabs on -ground in accordance with Section 1808.6.2 of the 2022 CBC and the PTI publication. Thicker floor slabs and larger footing sizes may be required for structural reasons and should govern the design if more restrictive than the minimum recommendations provided below:

1. Exterior continuous footings for one- and two-story structures should be founded at a minimum depth of 12 inches below the lowest adjacent finished ground surface. Interior footings may be founded at a minimum depth of 10 inches below the tops of the adjacent finish floor slabs.

2. In accordance with Table 1809.7 of 2022 CBC for light -frame construction, all continuous footings should have minimum widths of 12 inches for one- and two-story construction. We recommend all continuous footings should be reinforced with a minimum of two No. 4 bars, one top and one bottom.

Alternatively, post -tensioned tendons may be utilized in the perimeter continuous footings in lieu of the reinforcement bars.

3. A minimum 12 -inch -wide grade beam founded at the same depth as adjacent footings should be provided across the large entrances or similar openings (such as warehouse doors or bay windows).

The grade beam should be reinforced in a similar manner as provided above.

4. Interior isolated pad footings, if required, should be a minimum of 24 inches square and founded at a minimum depth of 12 inches below the bottoms of the adjacent floor slabs for one- and two-story buildings. Pad footings should be reinforced with No. 4 bars spaced a maximum of 18 inches on centers, both ways, placed near the bottoms of the footings.

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6. The thickness of the floor slabs should be determined by the project structural engineer with consideration given to the expansion index of the onsite soils; however, we recommend that a minimum slab thickness of 4 inches be considered.

7. As an alternative to designing 4 -inch -thick post -tensioned slabs with perimeter footings as described in Items 1 and 2 above, the structural engineer may design the foundation system using a thickened slab design. The minimum thickness of this uniformly thick slab should be 7.5 inches. The engineer in charge of post -tensioned slab design may also opt to use any combination of slab thickness and footing embedment depth as deemed appropriate based on their engineering experience and judgment.

8. Concrete floor slabs and areas to receive moisture sensitive floor covering should be underlain with a moisture vapor retarder consisting of a minimum 10 -mil -thick polyethylene or polyolefin membrane that meets the minimum requirements of ASTM E96 and ASTM E1745 for vapor retarders (such as Husky Yellow Guard®, Stego® Wrap, or equivalent). All laps within the membrane should be sealed, and at least 2 inches of clean sand should be placed over the membrane to promote uniform curing of the concrete. To reduce the potential for punctures, the membrane should be placed on a pad surface that has been graded smooth without any sharp protrusions. If a smooth surface cannot be achieved by grading, consideration should be given to lowering the pad finished grade an additional inch and then placing a 1 -inch -thick leveling course of sand across the pad surface prior to the placement of the membrane.

At the present time, some slab designers, geotechnical professionals and concrete experts view the sand layer below the slab (blotting sand) as a place for entrapment of excess moisture that could adversely impact moisture -sensitive floor coverings. As a preventive measure, the potential for moisture intrusion into the concrete slab could be reduced if the concrete is placed directly on the vapor retarder. However, if this sand layer is omitted, appropriate curing methods must be implemented to ensure that the concrete slab cures uniformly. A qualified materials engineer with experience in slab design and construction should provide recommendations for alternative methods of curing and supervise the construction process to ensure uniform slab curing. Additional steps would also need to be taken to prevent puncturing of the vapor retarder during concrete placement.

9. Presaturation of the subgrade below floor slabs will not be required; however, prior to placing concrete, the subgrade below all dwelling and garage floor slab areas should be thoroughly moistened to achieve a moisture content that is at least equal to or slightly greater than optimum moisture content. This moisture content should penetrate to a minimum depth of 12 inches below the bottoms of the slabs.

10. The minimum footing dimensions and reinforcement recommended herein may be modified (increased or decreased subject to the constraints of Chapter 18 of the 2022 CBC) by the structural engineer responsible for foundation design based on calculations, engineering experience and judgment.

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Foundation Excavation Observations
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All footing trenches should be observed by a representative of the project geotechnical consultant to document that they have been excavated into competent bearing soils prior to the placement of forms, reinforcement or concrete. The excavations should be trimmed neat, level and square. All loose, sloughed or moisture -softened soils and/or any construction debris should be removed prior to the placing of concrete. Excavated soils derived from footing and/or utility trenches should not be placed in building slab - on -grade areas or exterior concrete flatwork areas unless the soils are compacted to at least 90 percent of maximum dry density.

General Corrosivitv Screening
As a screening level study, very limited chemical and electrical tests were performed on samples considered representative of the onsite soils to identify potential corrosive characteristics of these soils. The common indicators associated with soil corrosivity include water-soluble sulfate and chloride levels, pH (a measure of acidity), and minimum electrical resistivity. Test results are presented in Table 4 below.

It should be noted that Petra does not practice corrosion engineering; therefore, the test results, opinion and engineering judgment provided herein should be considered as general guidelines only. Additional analyses would be warranted, especially for cases where buried metallic building materials (such as copper and cast or ductile iron pipes) in contact with site soils are planned for the project. In many cases, the project geotechnical engineer may not be informed of these choices.

Therefore, for conditions where such elements are considered, we recommend that other, relevant project design professionals (e.g., the architect, landscape architect, civil and/or structural engineer) also consider recommending a qualified corrosion engineer to conduct additional sampling and testing of near -surface soils during the final stages of site grading to provide a complete assessment of soil corrosivity. Recommendations to mitigate the detrimental effects of corrosive soils on buried metallic and other building materials that may be exposed to corrosive soils should be provided by the corrosion engineer as deemed appropriate.

In general, a soil's water-soluble sulfate levels and pH relate to the potential for concrete degradation; water-soluble chlorides in soils impact ferrous metals embedded or encased in concrete, e.g., reinforcing steel; and electrical resistivity is a measure of a soil's corrosion potential to a variety of buried metals used in the building industry, such as copper tubing and cast or ductile iron pipes. Table 4, below, presents test results. with an interpretation of current code indicators and guidelines that are commonly used in this industry. The table includes the classifications of the soils as they relate to the various tests, as well as a general recommendation for possible mitigation measures in view of the potential adverse impact on eGEOSCIENCES"`
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various components of the proposed structures in direct contact with site soils. The guidelines provided herein should be evaluated and confirmed, or modified, in their entirety by the project structural engineer, corrosion engineer and/or the contractor responsible for concrete placement for structural concrete used in exterior and interior footings, interior slabs on -ground, garage slabs, wall foundations and concrete exposed to weather such as driveways, patios, porches, walkways, ramps, steps, curbs, etc.

TABLE 4
Soil Corrosivity Screening Results
Classification
General Recommendations
Test
Test Results
Soluble Sulfates
(Cal

0.0018 percent
S0W No
Not Applicable
cement type restrictions; no water/cement ratio
restrictions;
min. f'c = 2,500 psi
pH
(Ca1 643)

7.5 Slightly Alkaline
No special recommendations
Soluble Chloride
(Ca1 422)
330 ppm
C1(2)
Moderate
C2(4)
Severe
Residence: No special recommendations, f'c
should not be less than 2,500 psi.

Pools & Decking: Water/cement ratio should not
exceed 0.40; min. f'e= 5,000 psi
Resistivity
(Cal 643)
20,000 ohm -cm
Mildly
Corrosive�3l
A corrosion engineer should be consulted for long
term protection of metallic elements in contact
with site soils
Notes:

1. ACI 318-14, Section 19.3

2. ACI 318-14, Section 19.3

3. Pierre R. Roberge, "Handbook of Corrosion Engineering"

4. Exposure classification C2 applies specifically to swimming pools and appurtenant concrete elements Post -Grading Considerations
Utility Trenches
All utility trenches backfill should be compacted to a minimum relative compaction of 90 percent. Due to the nature of the upper onsite earth materials, flooding and jetting techniques should be avoided. Therefore, trench backfill materials should be placed in lifts no greater than approximately 12 inches in thickness, watered or air-dried as necessary to achieve near optimum moisture conditions, and then mechanically compacted in place to a minimum relative compaction of 90 percent. A representative of the project geotechnical consultant should probe and test the backfills to verify adequate compaction.

As an alternative for shallow trenches where pipe or utility lines may be damaged by mechanical compaction equipment, such as under building floor slabs, imported clean sand having a sand equivalent PETRA
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(SE) value of 30 or greater may be utilized. The sand backfill materials should be watered to achieve near optimum moisture conditions and then tamped into place. No specific relative compaction will be required; however, observation, probing, and if deemed necessary, testing should be performed by a representative of the project geotechnical consultant to verify an adequate degree of compaction.

If clean, imported sand is to be used for backfill of exterior utility trenches, it is recommended that the upper 12 inches of trench backfill materials consist of properly compacted onsite soil materials. This is to mitigate infiltration of irrigation and rainwater into granular trench backfill materials.

Where an exterior and/or interior utility trench is proposed in a direction parallel to a building footing, the bottom of the trench should not extend below a 1:1 (horizontal to vertical) plane projected downward from the bottom edge of the adjacent footing. Where this condition occurs, the adjacent footing should be deepened, or the utility constructed and the trench backfilled and compacted prior to footing construction.

Where utility trenches cross under a building footing, these trenches should be backfilled with on -site soils at the point where the trench crosses under the footing to reduce the potential for water to migrate under the floor slabs.

Site Drainage
Positive surface drainage systems consisting of a combination of sloped concrete flatwork/asphalt pavement, sheet flow gradients, swales and surface area drains (where needed) should be provided around the building and within any planter areas to collect and direct all surface waters to an appropriate drainage facility as determined by the project civil engineer. The ground surfaces of planter and landscape areas that are located within 10 feet of building foundations should be sloped at a minimum gradient of 5 percent away from the foundations and towards the nearest area drains. The ground surface of planter and landscape areas that are located more than 10 feet away from building foundations may be sloped at a minimum gradient of 2 percent away from the foundations and towards the nearest area drains.

Concrete flatwork surfaces that are located within 10 feet of building foundations should be inclined at a minimum gradient of one percent away from the building foundations and towards the nearest area drains.

Concrete flatwork surfaces that are located more than 10 feet away from building foundations may be sloped at a minimum gradient of 1 percent towards the nearest area drains. Surface waters should not be allowed to collect or pond against building foundations and within the level areas of the site. All drainage devices should be properly maintained throughout the lifetime of the development. Future changes to site improvements, or planting and watering practices, should not be allowed to cause over -saturation of site soil adjacent to the structures.

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Bottomless Trench Drains
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When gravel filled bottomless infiltration systems are constructed near foundations, a potential exists for oversaturation of the foundation soils which conflicts with the intended purpose of onsite drainage facilities.

In addition, it has been our experience that a leading cause of distress to buildings and foundations is due to poor management of water next to building foundations. Petra recommends a setback of at least 15 feet between any infiltration system and building foundations. If this setback distance cannot be maintained, then a modified foundation system may be required to alleviate any distress that could be caused by infiltration of water near the footing. A modified foundation system could consist of constructing deepened footings within 15 feet of the infiltration system and installing extra reinforcement. Design of a modified foundation system is referred to the project structural engineer.

Retaining Walls
Due to the relatively flat and level site, it is anticipated that tall retaining walls will not be necessary for this project. Shorter retaining walls may be utilized for grading and landscaping purposes. Petra should be afforded the opportunity to review all proposed retaining wall design. Retaining walls retaining less than 6 feet of soil and without additional surcharge may be designed according to the following recommendations.

Allowable Bearing Values
Proposed retaining walls should be supported on spread footings using the design criteria recommended previously for building footings; however, when calculating passive resistance, the passive earth pressure for retaining walls supported by descending slopes should be reduced to 150 pounds per square foot, per foot of depth, to a maximum value of 1,500 pounds per square foot.

Active and At -Rest Earth Pressures

1. On -Site Soils Used for Backfill
On -site soil and bedrock materials have predominant very low expansion potentials. Therefore, for this condition, active earth pressures equivalent to fluids having densities of 35 and 51 pounds per cubic foot should be used for design of cantilevered walls retaining a level backfill and ascending 2:1 backfill, respectively. For walls that are restrained at the top, at -rest earth pressures of 53 and 78 pounds per cubic foot (equivalent fluid pressures) should be used. The above values are for retaining walls that have been supplied with a proper subdrain system (see Figure RW-1). All walls should be designed to support any adjacent structural surcharge loads imposed by other nearby walls or footings in addition to the above -recommended active and at -rest earth pressures.

2. Imported Sand, Pea Gravel, or Rock Used for Wall Backfill Imported clean sand exhibiting a sand equivalent value (SE) of 30 or greater, pea gravel, or crushed rock may be used for wall backfill to reduce the lateral earth pressures provided these granular backfill materials extend behind the walls to a minimum horizontal distance equal to one-half the wall height.

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In addition, the sand, pea gravel, or rock backfill materials should extend behind the walls to a minimum horizontal distance of 2 feet at the base of the wall or to a horizontal distance equal to the heel width of the footing, whichever is greater (see Figures RW-2 and RW-3). For the above conditions, cantilevered walls retaining a level backfill and ascending 2:1 backfill may be designed to resist active earth pressures equivalent to fluids having densities of 30 and 41 pounds per cubic foot, respectively. For walls that are restrained at the top, at -rest earth pressures equivalent to fluids having densities of 45 and 62 pounds per cubic foot are recommended for design of restrained walls supporting a level backfill and ascending 2:1 backfill, respectively. These values are also for retaining walls supplied with a proper subdrain system.

Furthermore, as with existing soil backfill, the walls should be designed to support any adjacent structural surcharge loads imposed by other nearby walls or footings in addition to the recommended active and at - rest earth pressures. All structural calculations and details should be provided to this firm for verification purposes prior to grading and construction phases.

Earthquake Loads Retaining Walls
Note 1 of Section 1803.5.12 of the 2022 CBC indicates that the dynamic seismic lateral earth pressures on foundation walls and retaining walls supporting more than 6 feet of backfill height due to design earthquake ground motions be determined. It is unlikely that any wall retaining 6 or more feet of backfill will be constructed onsite. Accordingly, dynamic seismic lateral earth pressures are not considered necessary for this project.

Subdrainage
Perforated pipe and gravel subdrains should be installed behind all retaining walls to prevent entrapment of water in the backfill (see Figures RW-1 through RW-3). Perforated pipe should consist of 4 -inch -minimum diameter PVC Schedule 40, or SDR-35, with the perforations laid down. The pipe should be encased in a 1 -foot -wide column of 3/4 -inch to 1 %Z -inch open -graded gravel. If on -site soils are used as backfill, the open - graded gravel should extend above the wall footings to a minimum height equal to one-third the wall height or to a minimum height of 1.5 feet above the footing, whichever is greater. If imported sand, pea gravel, or crushed rock is used as backfill, subdrain details shown on Figures RW-2 and RW-3 should be utilized.

The open -graded gravel should be completely wrapped in filter fabric consisting of Mirafi 140N or equivalent. Solid outlet pipes should be connected to the subdrains and then routed to a suitable area for discharge of accumulated water.

If a limited area exists behind the walls for installation of a pipe and gravel subdrain, a geotextile drain mat such as Mirafi Miradrain, or equivalent, can be used in lieu of drainage gravel. The drain mat should extend the full height and lengths of the walls and the filter fabric side of the drain mat should be placed up against PETRA
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the backcut. The perforated pipe drain line placed at the bottom of the drain mat should consist of 4 -inch minimum diameter PVC Schedule 40 or SDR-35. The filter fabric on the drain mat should be peeled back and then wrapped around the drain line.

Waterproofing
The portions of retaining walls supporting backfill should be coated with an approved waterproofing compound or covered with a similar material to inhibit infiltration of moisture through the walls.

Wall Backfill
Where imported sand (with a Sand Equivalent of 30 or greater) or the onsite soils materials are used as backfill behind the proposed retaining walls, the backfill materials should be placed in approximately 6- to 8 -inch -thick maximum lifts, watered as necessary to achieve above optimum moisture conditions, and then mechanically compacted in place to a minimum relative compaction of 90 percent. Flooding or jetting of the backfill materials should be avoided. A representative of the project geotechnical consultant should observe the backfill procedures and test the wall backfill to verify adequate compaction.

If imported pea gravel or rock is used for backfill, the gravel should be placed in approximately 2- to 3 - foot -thick lifts, thoroughly wetted but not flooded, and then mechanically tamped or vibrated into place. A representative of the project geotechnical consultant should observe the backfill procedures and probe the backfill to determine that an adequate degree of compaction is achieved.

To reduce the potential for the direct infiltration of surface water into the backfill, imported sand, gravel, or rock backfill should be capped with at least 12 inches of on -site soil. Filter fabric such as Mirafi 140N or equivalent, should be placed between the soil and the imported gravel or rock to prevent fines from penetrating into the backfill.

Geotechnical Observation and Testing
All grading and construction phases associated with retaining wall construction, including backcut excavations, footing trenches, installation of the subdrainage systems, and placement of backfill should be observed and tested by a representative of the project geotechnical consultant.

Masonry Block Walls
Footings for free-standing masonry block walls and other rigid structures should be designed and reinforced utilizing the criteria recommended for conventional building foundations. Where existing surface soils are not removed and re -compacted as recommended herein, the footings should be extended through these PETRA
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loose surface soils and founded in underlying competent materials. Positive separations in walls should also be provided at corners and at horizontal spacing of approximately 25 feet to permit relative movement. The separations should be provided in the blocks and not extend through the footings. The footings should be poured monolithically with continuous rebars to serve as effective "grade beams" below the walls.

Where remedial grading cannot be performed due to site constraints, a reduced bearing value of 1,200 pounds per square foot should be used for 12 -inch -wide continuous footings founded at a minimum depth of 12 inches below the lowest adjacent final grade. No increase in bearing value may be used for wider or deeper footings for this condition. The recommended allowable bearing value includes both dead and live loads and may be increased by one-third for short duration wind and seismic forces. In addition, a reduced passive earth pressure of 175 pounds per square foot per foot of depth, to a maximum value of 1,750 pounds per square foot, should be used to resist lateral loads. A coefficient of friction of 0.3 times the dead load forces may still be used between concrete and the supporting soils to determine lateral sliding resistance.

An increase of one-third of the above values may also be used when designing for short duration wind or seismic forces.

Exterior Concrete Flatwork
General
Near -surface compacted fill soils within the site are expected to exhibit an expansion index of 0 to 20, i.e. non -expansive. Subgrade preparation for areas not supported by the compacted fill supporting building structures should follow the guidelines presented below for pavement design and construction. We recommend that all exterior concrete flatwork such as sidewalks, patio slabs, large decorative slabs, concrete subslabs that will be covered with decorative pavers, vehicular driveways and/or access roads within and adjacent to the site be designed by the project architect and/or structural engineer with consideration given to mitigating the potential cracking and uplift that can develop in soils exhibiting expansion index values that fall in the very low category. The guidelines that follow should be considered as minimums and are subject to review and revision by the project architect, structural engineer and/or landscape consultant as deemed appropriate.

Thickness and Joint Spacing
To reduce the potential of unsightly cracking, concrete walkways, patio -type slabs, large decorative slabs and concrete subslabs to be covered with decorative pavers should be at least 4 inches thick and provided with construction joints or expansion joints every 6 feet or less. Private driveways that will be designed for the use of passenger cars for access to private garages should also be at least 4 inches thick and provided PETRA
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with construction joints or expansion joints every 10 feet or less. Concrete pavement that will be designed based on an unlimited number of applications of an 18 -kip single -axle load in public access areas, segments of road that will be paved with concrete (such as bus stops and cross -walks) or access roads that will be subject to heavy truck loadings should have a minimum thickness of 5 inches and be provided with control joints spaced at maximum 10 -foot intervals. A modulus of subgrade reaction of 125 pounds per cubic foot may be used for design of the public and access roads.

Reinforcement
All concrete flatwork having their largest plan -view panel dimension exceeding 10 feet should be reinforced with a minimum of No. 3 bars spaced 24 inches on centers, both ways. Alternatively, the slab reinforcement may consist of welded wire mesh of the sheet type (not rolled) with 6x6/W 1.4xW 1.4 designation in accordance with the Wire Reinforcement Institute (WRI). The reinforcement should be properly positioned near the middle of the slabs.

The reinforcement recommendations provided herein are intended as guidelines to achieve adequate performance for anticipated soil conditions. The project architect, civil and/or structural engineer should make appropriate adjustments in reinforcement type, size and spacing to account for concrete internal (e.g., shrinkage and thermal) and external (e.g., applied loads) forces as deemed necessary.

Edge Beams (Optional)
Where the outer edges of concrete flatwork are to be bordered by landscaping, it is recommended that consideration be given to the use of edge beams (thickened edges) to prevent excessive infiltration and accumulation of water under the slabs. Edge beams, if used, should be 6 to 8 inches wide, extend 8 inches below the tops of the finish slab surfaces. Edge beams are not mandatory; however, their inclusion in flatwork construction adjacent to landscaped areas is intended to reduce the potential for vertical and horizontal movement and subsequent cracking of the flatwork related to uplift forces that can develop in expansive soils.

Subgrade Preparation
Compaction
To reduce the potential for distress to concrete flatwork, the subgrade soils below concrete flatwork areas to a minimum depth of 12 inches (or deeper, as either prescribed elsewhere in this report or determined in the field) should be moisture conditioned to at least equal to, or slightly greater than, the optimum moisture content and then compacted to a minimum relative compaction of 90 percent. Where concrete public roads, 0 GEOSCIENCES"'
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concrete segments of roads and/or concrete access driveways are proposed, the upper 6 inches of subgrade soil should be compacted to a minimum 95 percent relative compaction.

Pre -Moistening
As a further measure to reduce the potential for concrete flatwork cracking, subgrade soils should be thoroughly moistened prior to placing concrete. The moisture content of the soils should be at least the optimum moisture content to a minimum depth of 12 inches into the subgrade. Flooding or ponding of the subgrade is not considered feasible to achieve the above moisture conditions since this method would likely require construction of numerous earth berms to contain the water. Therefore, moisture conditioning should be achieved with sprinklers, or a light spray applied to the subgrade over a period of few to several days just prior to pouring concrete. Pre -watering of the soils is intended to promote uniform curing of the concrete, reduce the development of shrinkage cracks and reduce the potential for differential expansion pressure on freshly poured flatwork. A representative of the project geotechnical consultant should observe and verify the density and moisture content of the soils, and the depth of moisture penetration prior to placing concrete.

Drainage
Drainage from patios and other flatwork areas should be directed to local area drains and/or graded earth swales designed to carry runoff water to the adjacent streets or other approved drainage structures. The concrete flatwork should be sloped at a minimum gradient of one percent, or as prescribed by project civil engineer or local codes, away from building foundations, retaining walls, masonry garden walls and slope areas.

Tree Wells
Tree wells are not recommended in concrete flatwork areas since they introduce excessive water into the subgrade soils and allow root invasion, both of which can cause heaving and cracking of the flatwork.

Swimming Pool and Spa
Allowable Bearing and Settlement
Plans for the proposed project were not made available to Petra at the time this report was prepared, but it is common to include one (or more) pools in a multi -unit apartment complex. If a pool is proposed for the project, the pool may be designed as a conventional pool shell founded on natural, medium dense eolian sand. Any loose sand below the pool shell should be removed and replaced with engineered fill. Therefore, the pool shell may be designed using an allowable bearing value of 1,500 pounds per square foot. A eGEOSCIENCES"'c
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potential for seismic differential settlement on the order of one inch to occur across the pool/spa shells should be considered in the design. Petra should review final plans when available to verify there are no additional geotechnical concerns related to the construction of a pool.

Lateral Earth Pressures
The pool walls should be designed assuming that an earth pressure equivalent to a fluid having a density of 90 pounds per cubic foot is acting on the outer surface of the pool walls. For this long-term condition, the walls should be designed using a lateral earth pressure of 62.4H pounds per square foot (where "H" equals the vertical depth in feet below the ground surface) that is acting on the inner surface of the pool walls. Pool walls should also be designed to resist lateral surcharge pressures imposed by any adjacent footings or structures in addition to the above lateral earth pressures.

Stability of Temporary Excavation
The pool excavation is expected to expose loose to medium dense eolian sand soil. Based on the anticipated physical characteristics of these materials, the pool excavation sidewalls will not remain stable at a vertical gradient during construction of the pool. Therefore, the temporary excavation sidewalls should be sloped at a slope ratio of 2:1 (horizontal to vertical) or flatter before forming of the pool walls.

Temporary Access Ramps
It is essential that all backfill placed within temporary access ramps extending into the pool excavation be properly compacted and tested. This will reduce the potential for excessive settlement of the backfill and subsequent damage to pool decking or other structures placed on the backfill.

Pool Bottom
It is expected that the swimming pool bottom will rest entirely on medium dense to dense eolian sand deposits. Therefore, care should be taken while excavating these structures to prevent disturbance of subgrade soils exposed at grade in the pool bottom.

Pool Decking
Pool decking should be constructed in accordance with the recommendations presented in the "Exterior Concrete Flatwork" section of this report.
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Leakage from the swimming pool or from any of the appurtenant plumbing could create adverse saturated conditions of the surrounding subgrade soils. Localized areas of oversaturation can lead to differential expansion (heave) of the subgrade soils and subsequent raising and shifting of concrete flatwork. Therefore, it is essential that all plumbing and pool fixtures be absolutely leak -free. For similar reasons, drainage from pool deck areas should be directed to local area drains and/or graded earth swales designed to carry runoff water to a suitable discharge point.

ACCESS ROADS
Asphalt Pavement
The proposed site improvements may include construction of new asphalt -paved roads, as well as improvements to the existing nearby access roads. We have developed the following preliminary recommendations for flexible pavement design based on an assumed R -value of 40 and using Traffic Index (TI) values of 5.0 and 6.0. The pavement design presented herein is based on the assumption that the pavement will be placed directly over engineered, compacted fill placed as specified above in the section for Subgrade Preparation of Exterior Concrete Flatwork.

R -value and traffic index parameters presented herein have been assumed. We recommend that bulk samples of the actual subgrade materials be collected and R -Value tested after rough grading is completed.

Additionally, the project civil engineer should be consulted to determine appropriate or required TI values.

Once actual as -graded testing is complete and traffic loads are confirmed, additional or modified design recommendations may be presented.

The pavement section thicknesses presented in Table 5 are considered as minimums for the subject site under the assumed conditions and may be superseded by the project requirements or jurisdictional agency specifications if more stringent.

TABLE 5
Suggested Minimum Flexible Pavement Thickness
Traffic Index
R Value
Hot Mix Asphalt (alternative)
(inches)
Aggregate Base
(inches)

5.0 (Light Traffic)
40 3
4 6.0 (Truck Traffic)
40 3

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Subgrade soils should be properly compacted, smooth, and non -yielding prior to pavement construction.

The subgrade soils should be compacted to at least 90 percent of ASTM D 1557-07. Subgrade preparation recommendations are provided below.

Aggregate base materials may consist of Crushed Aggregate Base, Crushed Miscellaneous Base, or Processed Miscellaneous Base conforming to Section 200-2 of the Standard Specifications for Public Works Construction (Greenbook). It should be noted that base thicknesses recommended above are based on the use of Crushed Aggregate base material. For conditions where either Crushed Miscellaneous Base or Processed Miscellaneous Base Materials are used, a 10 percent increase in base section thickness should be incorporated in the design and construction of the structural pavement section.

The base materials should be brought to a uniform moisture near optimum moisture then compacted to at least 95 percent of ASTM D 1557. Asphaltic concrete materials and construction should conform to Section 203 of the Greenbook.

Subgrade drainage is an important factor that enhances pavement performance. Subgrade surfaces below the flexible pavement structural section should be sloped to direct run-off to suitable collection points and to prevent ponding. The roadways should be raised above the surrounding ground surface to facilitate drainage from the roadway.

PLAN REVIEW
This report is based on certain assumptions related to the proposed development, since no plans were available for Petra's review at the time this report was prepared. We recommend that our firm be engaged to review the final design drawings, specifications and grading plan prior to any new construction. If we are not provided the opportunity to review these documents with respect to the geotechnical aspects of new construction and grading, it should not be assumed that the recommendations provided herein are wholly or in part applicable to the proposed construction.

REPORT LIMITATIONS
This report is based on Petra's understanding of the proposed project and geotechnical data as described herein. The materials encountered on the project site, described in other literature, and utilized in our laboratory investigation are believed representative of the project area, and the conclusions and recommendations contained in this report are presented on that basis. However, soil materials can vary in characteristics between points of exploration, both laterally and vertically, and those variations could affect the conclusions and recommendations contained herein. As such, observation and testing by a geotechnical eGEOSCIENCES".

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consultant during the grading and construction phases of the project are essential to confirming the basis of this report. To provide the greatest degree of continuity between the design and construction phases, consideration should be given to retaining Petra Geosciences, Inc., as geotechnical engineer of record for construction services.

This report has been prepared consistent with that level of care being provided by other professionals providing similar services at the same locale and time period. The contents of this report are professional opinions and as such, are not to be considered a guarantee or warranty.

This report should be reviewed and updated after a period of one year or if the project concept changes from that described herein.

The information contained herein has not been prepared for use by parties or projects other than those named or described herein. This report may not contain sufficient information for other parties or other purposes.

This report is subject to review by the controlling authorities for this project. Should you have any questions, please do not hesitate to call.

Respectfully submitted,
PETRA GEOSCIENCES, INC.

Alan Pace
Senior Associate Geologist
CEG 1952
KTM/KB/AP/SJ/lv
NO. EG1952

CERTIFIED

ENGINEERING

GEOLOGIST
W.\2020-2025\2024\100\24-112\Reports\24-112 110 Design -Phase Geotechnical Repott.docx Siamak Jafroudi, PhD
Senior Principal Engineer
GE 2024
0 GEOSCIENCES''
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REFERENCES
American Concrete Institute (ACI), Building Code Requirements for Structural Concrete ACI 318-14.

American Society for Testing and Materials (ASTM) — Standard — Section Four — Construction, Volume 04.08 Soil and Rock.

American Society of Civil Engineers (ASCE) and Structural Engineering Institute (SEI), 2017, Minimum Design Loads and Associated Criteria for Buildings and Other Structures (ASCE 7-16).

A. O. Architects, 2024, Draft Site Plan, Via Vail Village, Rancho Mirage, California, The Pacific Companies, Job Number 2023-0361, dated March 8.

Bryant and Hart, E.W., W.A., 2007, Fault -Rupture Hazard Zones in California, Alquist-Priolo Earthquake Fault Zoning Act with Index to Earthquake Fault Zones Maps; California Geological Survey, Special Publication 42, interim revision.

California Building Standards Commission, 2022, California Building Code, California Code of Regulations, Title 24, Part 2, Volume 1 of 2, dated June.

California Building Standards Commission, 2022, California Building Code, California Code of Regulations, Title 24, Part 2, Volume 2 of 2, dated June.

California Department of Water Resources, "Water Data Library (WDL) Station Map", Groundwater Monitor Wells, accessed 1/24/2023, https://wdl.water.ca.gov/Map.aspx
California Geologic Survey, 2008, Special Publication 117A. , 2020, Earthquake Zones of Required Investigation, Rancho Mirage Quadrangle, accessed July, https://maps.conservation.ca.gov/cgs/EQZApp/app/
Cetin,K. et al, 2009, Probabilistic Model for the Assessment of Cyclically Induced Reconsolidation (Volumetric) Settlements, in Journal of Geotechnical and Geoenvironmental Engineering: Vol. 135, No. 3.

County of Riverside Safety Element, 2003, Chapter 6 of the General Plan (adopted October 7, 2003).

Dibblee, T.W., 1953, "Generalized geologic map of Imperial Valley region, California": in Jahns, R.A., (ed.), 1954, Geology of southern California: California Division of Mines and Geology Bulletin 170 (scale 1" = 6 miles).

Dillon, J.T., and Ehlig, P.L., 1993, Displacement on the Southern San Andreas Fault: in Powell, R.E., Weldon, R.J.II, and Matti, J.C., eds, The San Andreas Fault System: Displacement, Palinspastic Reconstruction, and Geologic Evolution: Geological Society of America Memoir 178.

Frost, E.G., Suitt, S.C., and Fattahipour, M., 1997, Emerging Perspectives of the Salton Trough Region with an Emphasis on Extensional Faulting and its Implications for Later San Andreas Deformation: South Coast Geological Society Annual Field Trip Guide Book no. 25, p. 57-97.

Fumal, T.E., Rymer, M.J., and Seitz, G.G., 2002, Timing of Large Earthquakes since A.D., 800 on the Mission Creek Strand of the San Andreas Fault Zone at Thousand Palms Oasis Near Palm Springs, California: Bulletin of the Seismological Society of America, v. 92, p. 2841- 2860.

Google EarthTM 2020, by Google Earth, Inc., http://www.google.com/earth/index.html/ , accessed March.

Ishihara, K., 1985, Stability of Natural Deposits During Earthquakes, 11th International Conference on Soil Mechanics and Foundation Engineering, Proceedings, San Francisco, Vol. 1., pp. 321-376. eGEOSCIENCES".

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REFERENCES
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Jennings, C.W., 1975, Fault map of California with location of volcanoes, Thermal Springs, and Thermal Wells:

California Division of Mines and Geology, Geological Data Map Series, Map No. 2.

Jones, L.M., 1988, Focal Mechanisms and the State of Stress on the San Andreas Fault in Southern California: Journal of Geophysical Research, v. 93, p. 8869-8891.

Macedo, J. and Bray, D., 2018, Key Trends in Liquefaction -Induced Building Settlement, in Journal of Geotechnical and Geoenvironmental Engineering: Vol. 144, No. 11.

Philibosian, B., Fumal, T.E. & Weldon, R., 2011, San Andreas Fault earthquake chronology and Lake Cahuilla history at Coachella, California: Bulletin of the Seismological Society of America, Volume 101, No. 1, p13-38.

Pradel, D., 1998, Procedure to Evaluate Earthquake -Induced Settlements in Dry Sandy Soils: in Journal of Geotechnical and Geoenvironmental Engineering: Vol. 124, No. 4.

Sieh, K.E., and Williams, P.L., 1990, Behavior of the Southernmost San Andreas Fault during the Past 300 Years:

Journal of Geophysical Research, v. 95, p. 6629-6645.

Smith, Merrit, 1964, Map Showing Distribution and Configuration of Basement Rocks in California (South Half), United States Geological Survey, Oil and Gas Investigations, Map OM -215 (Sheet 2 of 2).

Sneed 2001; Detection and Measurement of Land Subsidence Using Global Positioning System and Interferometric Synthetic Aperture Radar, Coachella Valley, California, 1996-1998, U.S. Geological Survey, Water - Resources Investigations Report 01-4193.

Sneed 2007; Detection and Measurement of Land Subsidence Using Global Positioning System Surveying and Interferometric Synthetic Aperture Radar, Coachella Valley, California, 1996-2005, Scientific Investigations Report 2007-5251, United States Geological Survey.

Sneed, M., Brandt, J.T., Solt, M., 2014, Land Subsidence, Groundwater Levels, and Geology in the Coachella Valley, California, 1993-2010, USGS, Scientific Investigation Report 2014-5075.

Southern California Earthquake Center (SCEC), 1999, Recommended Procedures for Implementation of DMG Special Publication 117, Guidelines for Analyzing and Mitigating Liquefaction Hazards in California:
organized through the Southern California Earthquake Center, University of Southern California.

Standard Specifications for Public Works Construction The "Greenbook", 2018 edition, BNi Publications, Inc.

Structural Engineers Association of California (SEAOC)/Office of Statewide Health Planning and Development (OSHPD), 2018, U. S. Seismic Design Maps, https://seismicmaps.org/ .

Tokimatsu, K. and Seed, H.B., 1987; Evaluation of Settlements in Sands due to Earthquake Shaking: in Journal of Geotechnical Engineering, Vol. 113, No. 8, p. 861-879.

United States Geological Survey (USGS), 2014, Unified Hazard Tool, https://earthquake.usgs.gov/hazards/interactive/
Working Group on California Earthquake Probabilities (WGCEP), Field, E.H., Biasi, G.P., Bird, P., Dawson, T.E., Felzer, K.R., Jackson, D.D., Johnson, K.M., Jordan, T.H., Madden, C., Michael, A.J., Milner, K.R., Page, M.T., Parsons, T., Powers, P.M., Shaw, B.E., Thatcher, W.R., Weldon, R.J., II, and Zeng, Y., 2013, Uniform California earthquake rupture forecast, version 3 (UCERF3) — The time -independent model: U.S.

Geological Survey Open -File Report 2013-1165, 97 p., California Geological Survey Special Report 228, and Southern California Earthquake Center Publication 1792, http://pubs.usgs.gov/of/2013/1165/ eGEOSCIENCES".

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FIGURES
0 PETRAES 435
GEOSCIENC ^

NATIVE SOIL BACKFILL
H
h*
H/3
Sloped or level ground surface
Compacted on -site soil
Recommended backcut*
Waterproofing compound
Install subdrain system
Minimum 12 -inch -wide column of 3/4" - 1 1/2"
open graded gravel wrapped in filter fabric.

Filter fabric (should consist of
Mirafi 140N or equivalent)
4 inch perforated pipe. Perforated pipe should
consist of 4" diameter ABS SDR-35 or PVC
Schedule 40 or approved equivalent with the
perforations laid down. Pipe should be laid on
at least 2 inches of open -graded gravel.
* Vertical height (h) and slope angle
of backcut per soils report. Based
on geologic conditions, configuration
of backcut may require revisions
(i.e. reduced vertical height,
revised slope angle, etc.)
PETRA

RETAINING WALL BACKFILL

AND SUBDRAIN DETAILS
FIGURE RW-1

IMPORTED SAND BACKFILL
H
1/2 H _
Sloped or level ground surface
On -site native soil cap
(12" thick)
Non -expansive imported
sand, SE>30.

Waterproofing compound
Install subdrain system
1 cubic foot per foot min. of 3/4" - 1 1/2"
open graded gravel wrapped in filter
fabric.

Filter fabric (should consist of
Mirafi 140N or equivalent).
4 inch perforated pipe. Perforated pipe should
•j consist of 4" diameter ABS SDR-35 or PVC
Schedule 40 or approved equivalent with the
perforations laid down. Pipe should be laid on
at least 2 inches of open -graded gravel.
* At base of wall, the non -expansive
backfill materials should extend to a
min. distance of 2' or to a horizontal
distance equal to the heel width of
the footing, whichever is greater.

PETRA

RETAINING WALL BACKFILL

AND SUBDRAIN DETAILS
FIGURE RW-2
437 _

IMPORTED GRAVEL OR CRUSHED ROCK BACKFILL
H
2` min.*
Sloped or level ground surface
,�1 On -site native soil cap
/2 H.•`. ::•''.:•'.• ,:•''. •'.:•.,. -:!t (12" thick)
Z -Non -expansive imported
gravel or crushed rock
Install filter fabric (Mirafi 140N
or equal) to prevent migration
of fines into backfill.

Waterproofing compound
4 inch perforated pipe. Perforated pipe should
consist of 4" diameter ABS SDR-35 or PVC Schedule 40 or approved equivalent with the perforations laid down. If pea gravel used,
pipe should be encased in 1 cubic foot per
foot min. of 3/4" - 1 1/2" open -graded gravel
wrapped in filter fabric (Mirafi 140N or equal)
Pipe should be laid on at least 2 inches of
gravel.
* At base of wall, the non -expansive
backfill materials should extend to a
min. distance of 2' or to a horizontal
distance equal to the heel width of
the footing, whichever is greater.

PETRA

RETAINING WALL BACKFILL

AND SUBDRAIN DETAILS
FIGURE RW-3

RAMON RD
GERALD FORD DR_
CYPRESS.

Scale: 1" = 2,000'

LA COSTA DP

HILTON HEAD DR
■

SHERWOOD RD
ORPORA7E,

VIA VAI
DINAH. SHORE DR
I I z
VICTORY DR w

GINGER ROGERS RD

FRANK SINATRA DR
SW of Monterey Ave. & Dinah Shore Dr.

Rancho Mirage, California
,VIA FLORENCIA
I i C

PROVENCE DR

DATA RD

HASKELL RD
45'ii TL '
Base Map: Portions of USGS Palm S�rittigrfL1atnearal City, Myoma, Rancho 5 Mirage, and La Quinta Quadrangles /linute Topographic Ser'es, 2015 w
v
;Thousand
Palms

RAMON RD
BROAD

CA CHI CA
H AVE t "DER OR
PETRA GEOSCIENCES, INC.
3186 Airway Avenue, Suite K
Costa Mesa, California 92626
PHONE: (714) 549-8921

COSTA MESA TEMECULA LOS ANGELES PALM DESERT CORONA ESCONDIDO

SITE LOCATION MAP
PETRA
O EOSCIENICES"
DATE: July, 2024
J.N.: 24-112
Figure 1

•
Base Map: Google Earth, 2024.
_AMs _
a
t
B-1
TD=66'
•
•
4 A
•
TD=26' TD=26' TD=10'
440 _
0 j/1
200
400
Scale: 1" = 200'
PETRA GEOSCIENCES, INC.
3186 Airway Avenue, Suite K
Costa Mesa, California 92626
PHONE: (714) 549-8921

COSTA MESA TEMECULA LOS ANGELES PALM DESERT CORONA ESCONDIDO

BORING LOCATION MAP
SW of Monterey Ave. & Dinah Shores Dr.

Rancho Mirage, California
PIETRA
I DATE: July, 2024
Ci EGSCIEN ES°" J.N.: 24-112
Figure 2
F

APPENDIX A

BORING LOGS
PETRAS 441
GEOSCIENCE^
SOt ID AS A ROCK

Key to Soil and Bedrock Symbols and Terms
Unified Soil Classification System
Fine-grained Soils Coarse -grained
> 1t2 of materials is Soils
smaller than #200 > 1/2 of materials is
sieve larger than #200
sieve
The No. 200 U.S. Standard Sieve is about the
smallest article visible to the naked e e

GRAVELS
more than half of coarse
fraction is larger than #4
sieve
Clean Gravels
(less than 5% fines)
GW
Well -graded gravels, gravel -sand mixtures, little or no fines CF
Poorly -graded gravels, gravel -sand mixtures, little or no fines Gravels
with fines
GM
Silty Gravels,,poorly-graded gravel -sand -silt mixtures GC
Clayey Gravels, poorly -graded gravel -sand -clay mixtures SANDS
more than half of coarse
fraction is smaller than #4
sieve
Clean Sands
(less than 5% fines)
SW
Well -graded sands, gravelly sands, little or no fines
SP
Poorly -graded sands, gravelly sands, little or no fines Sands
with fines
SM
Silty Sands, poorly -graded sand -gravel -silt mixtures SC
Clayey Sands, poorly -graded sand -gravel -clay mixtures

SILTS & CLAYS
Liquid Limit
Less Than 50
ML
Inorganic silts & very fine sands, silty or clayey fine sands, clayey silts with slight plasticity
CL
Inorganic clays of low to medium plasticity, gravelly clays, sandy clays, silty clays, lean clays
OL
Organic silts & clays of low plasticity

SILTS & CLAYS
Liquid Limit
Greater Than 50
MH
Inorganic silts, micaceous or diatomaceous fine a sand or silt CH
Inorganic clays of high plasticity, fat clays
OH
Organic silts and clays of medium -to -high plasticity
Highly Organic Soils
PT
Peat, humus swamp soils with high organic content
Grain Size
Description
Sieve Size
Grain Size
Approximate Size
Boulders
>12"
>12"
Larger than basketball -sized
Cobbles
3 - 12"
3 - 12"
Fist -sized to basketball -sized
Gravel
coarse
3/4 - 3"
3/4 - 3"
Thumb -sized to fist -sized
fine
#4 - 3/4"

0.19 - 0.75"
Pea -sized to thumb -sized -
Sand
coarse
410 - #4

0.079 - 0.19"
Rock salt -sized to pea -sized
medium
#40 - #10

0.017 - 0.079"
Sugar -sized to rock salt -sized
fine
#200 - #40

0.0029 - 0.017""
Flour -sized to sugar -sized to
Fines
Passing #200
<0.0029"
Flour -sized and smaller
Laboratory Test Abbreviations
MAX
Maximum Dry Density
MA
Mechanical (Particle Size) Analysis
EX?
Expansion Potential
AT
Atterberg Limits
SO4
Soluble Sulfate Content
#200
#200 Screen Wash
RES
Resistivity
DSU
Direct Shear (Undisturbed Sample)
pH
Acidity
DSP.

Direct Shear (Remolded Sample)
CON
Consolidation
HYD
Hydrometer Analysis
SW
Swell
SE
Sand Equivalent
CL
Chloride Content
OC
Organic Content
RV
R -Value
COMP
Mortar Cylinder Compression
Modifiers
Trace
< 1%
Few
1 - 5%
Some
5 - 12'/e
Numerous
12-20%
Bedrock Hardness
Can be crushed and granulated by
Soft
hand; 'sail like' and sYn.r,.;lureless
Can be grooved with fingernails;
Moderately
gouged easily with butler knife;
hlard
raurnbles under tight hammer blows
Cannot break by hand; can be
Hard
grooved with a sharp knife; breaks
with a moderate hummer blow
Very Hard
Sharp knife leaves scratch; chips
with repeated hammer blows
Sampler and Symbol Descriptions
7 Approximate Depth of Groundwater Encountered
Approximate Depth of Standing Groundwater
1 D
L
Modified California Split Spoon Sample El
Standard Penetration Test
No Recovery in SPT Sampler
D
No Recovery in Mod. Calif. Split Spoon Sample
Shelby Tube Sample
No Recovery in Shelby Tube
Bulk Sample
Notes:

Blows Per Foot: Number of blows required to advance sampler 1 foot (unless a lesser distance is specified). Samplers in general were driven into the soil or bedrock at the bottom of the bole with a standard (140 lb.) hammer dropping a s inches unless noted otherwise in Log Notes. Drive samples collected in bucket auger borings maybe obtained by dropping non-standard weight fro ghts. When a SPT sampler is used the blow count conforms to ASTM D -1 516

EXPLORATION LOG
Project: A-2 Rancho Mirage Apartments
Boring No.: B-1
Location: Rancho Mirage
Elevation: ±307'
Job No.: 24-112
Client: National Core
Date: 6/7/2024
Drill Method: 8" Hollow Stem Auger
Driving Weight:

Logged
By: KTM
Depth
(Feet)
Lith-
ology
Material Description T o u
w
A
E
R
Samples
Laboratory Tests
Blows
per
6 in.

C
r
e
B
I
k
Moisture
Content
(0/0)
Dry
Density
(pcf)
Other
Lab
Tests
0 —
— °1.1:1;
—I
' ':
a•1.

I i:r r P.1.:

Ial :r• r. + ::
rt:
r. r
. . r,a..:
:

I :i:c r r: 1 :
:1 : : 1: 1 :

I.1 : is 1; 1-1:

EOLIAN DEPOSITS (Qe)
fine-grained sand.

MAX, EI, pH,
-dense, fine- to
dry, medium -dense,
6 8
13 6
0 11
4 5
8 10
15 12
22 13
25 41
8 14
20 9
16 21

0.6 0.7

0.8 0.6

0.6 0.6

0.8 102.8

98.7 RES, CL,
SO4, DSR
COL
Sand with Silt (SP-SM): Gray, dry, loose,
: Becomes medium -dense.
@2'ir.
—
Sand (SP): Off-white to gray, dry, medium
medium -grained sand.

I—
—'-.::.,,:',
—I.I,I:f .t:
—
—1
15—I°:1:IH:
—.I:i,
—
_
20—
—
-°I.1:I.I:
25-1.1.:1.•
—I'
—I.1:I:
—
—Ivi°I:p:i-i:
—
—
.;- : r r 1, °
, :1 :1: ' '::
°d :1: ( i.j :
:I. °::r 1.1.:
it:: °t:
:ra.::

I •I I: I: f i
i1:cri ':

I .r r r: i' t
:I ':ia ::
a°I°. . l°. ° 11°
I. ::
::i•'o-t°•
a°.r.r:i°t.
:.i:f i .1.. •
;I:I: 1 C1:
:I :1: I. i {:
6'1:
° °.I: r. a° t:
° : : 1, t1:
1 4°

1. :I I: t r.
•
:k is i i. :
.1:I: r P.1 :
1 ' 1 :ra.t:

I: r!:
°1 '1: 1' 1 t;
I °. :1: 6, 1.i :
i:

H C[if:
: :I: i: : ::

I.L'a:ra..:

I °II: 1;p{:
1 : 1 :1: I: i't:

I°I:I: i.'I:V:.
1,i:rr: i°is
LL.°rr1.c•
Sand with Silt (SP-SM): Gray to off-white• ,
fine -to medium -grained sand.
@20': Becomes dense.
rr
r
PLATE A-1
Petra Geosciences, Inc.
443

Logged
By: KTM
Depth
(Feet)
Lith-
ology
Material Description
w
A
T
T
E
R
Samples
Laboratory Tests
Blows
per
6 in.

C
o
r
e
B
u
I
k
Moisture
Content
(%)
Dry
Density
(pcf)
Other
Lab
Tests

1.I
-1
40-'E1:i
—:I
i:i.-.l:r7.r.:
45 —.5:
111:I;!;
_:I°{'
50 _.........
---.1:•1
—:
55 J•i3:
—7:1.7:66°J,P.:
—'1I;I:I:i°7
-:I
�d'i:1:1.1:it
—5:1:1:1:7 1:
11 65—a:,
—
—
:.7 .'i :
; ;1 .1. I. 1 4;
I.I. i. 1-1,
:1,v.r: i a t :
°J::J• I.
• "I' Ij 1.i.!
El: E f t;
:rJ3:L'I:r:
:1:L7.t°7°c:
.1:I: I; i 8:
j : 1 :1: i• i 1 :
.I °.1. I. J.
1 .1 :1: I.
fi c i; i E:
•
d , .1. I. I.

J' I,,;
5 :1 :1: 1: 1 [:
e1: I. °I: y'.
:I.Y:I: t. J'l:
•1 :I :I: I; t• i
'I :I :1: 1: 1 I:
� ,:I;1, !•r:
aa:f. r.rl:
d•pi;f••1:•
:I ...irir r r,i:
.•1.1• 11. V•°
Y .1 1: 1r t' ! ,•
II: r. a 1:
°J :1: I r. J :
1 . 1 -1' 1 1 fp
..•,i:i: Jr
f. 1.1
r.°I:r•.
:I °J :I: i: L J :
:I .1:1: 1; i 8 :
}i
°J°i 3:L°1:f•.
°t4:1: I: J, 1 :
1;1.7: ii.r.:
q:i _I: ; J e:
.1 .1°1: I° t.. { :
:L{.1: I••I. V°•
.7:C t, J'l:
a:ia•G:
1 is
I:I: 0.5
,I.9J:671:
@50': Becomes dense.
@60': Becomes medium -dense.
@65': Becomes dense.
9 20
27 10
16 17
5 13
10 17
26 10
2417
4 7
9 18
34 r35

0.4 0.6

0.4 0.4

0.5 0
Total Depth= 66.5'
No groundwater encountered
Boring backfilled with cuttings.

PLATE A-1
Petra Geosciences, Inc.
444

EXPLORATION LOG
Project: A-2 Rancho Mirage Apartments
Boring No.: B-2
Location: Rancho Mirage
Elevation: ±313'
Job No.: 24-112
Client: National Core
Date: 6/7/2024
Drill Method: 8" Hollow Stem Auger
Driving Weight:

Logged By: KTM
Depth
(Feet)
Lith-
ology
Material Description T o u
W
A
E
R
Samples
Laboratory Tests
Blows
per
6 in.

C
r
e
B
I
k
Moisture
Content
(%)
Dry
Density
(pcf)
Other
Lab
Tests
0 ' i;' is
r°i:t. c.

EOLIAN DEPOSITS (Qe)

2.0 1.9

1.6 0.3

0.3 105.1
107.3
Sand with Silt (SP-SM): Gray, dry, loose, fine-grained sand. 6 9
14 Sand (SP): Gray, dry, merdium-dense, fine- to medium -grained 5 10
15 20
25 30
• ::
sand.
@7.5': Becomes dry.
@15': Becomes gray to off-white.
@20': No recovery.
3 6

LLLJJJJ
Tr
9 13 _
2 4
6 I—
Tr
11 17
30 U
7 10 _
14 Total Depth= 21.5'
No groundwater encountered
Boring backfilled with cuttings.

PLATE A-2
Petra Geosciences, Inc.
445

EXPLORATION LOG
Project: A-2 Rancho Mirage Apartments
Boring No.: B-3
Location: Rancho Mirage
Elevation: ±308'
Job No.: 24-112
Client: National Core
Date: 6/7/2024
Drill Method: 8" Hollow Stem Auger
Driving Weight:

Logged By: KTM
Depth
(Feet)
Lith-
ology
Material Description T o u
W
A
E
R
Samples
Laboratory Tests
Blows
per
6 in.

C
r
e
B
I
k
Moisture
Content
(°/a)
Dry
Density
(pcf)
Other
Lab
Tests
0 —
—
•'''!`'F.i i"'
ri•a • I
I ;i; : o- r i -I
•
• 'r. r: ,° :
: . : ,:.I.:
.II: s t i.. : :

H is
I .1 : f:.i- is
EOLIAN DEPOSITS (Qe)

1.2 1.011

0.7 0.5

0.3 0.4
105.0
Sand with Silt (SP-SM): Gray, dry, loose, fine-grained sand. 4 6
5Tr
@2': Becomes medium -dense.

Sand (SP): Gray to off-white, dry, medium -dense, fine-grained 6 1U
—
—
15—'. i
-
20- @20':
—
—
25 —
30 -
:
is
sand.
@7.5': Becomes gray with fine- to medium -grained sand.

Becomes very dense.
2 5
5 9
16 U
6 9
13 Tr
22 43
50/4"
U
Total Depth= 21.5'
No groundwater encountered
Boring backfilled with cuttings.

PLATE A-3
Petra Geosciences, Inc.
446

EXPLORATION LOG
Project: A-2 Rancho Mirage Apartments
Boring No.: P-1
Location: Rancho Mirage
Elevation: ±308'
Job No.: 24-112
Client: National Core
Date: 6/7/2024
Drill Method: 8" Hollow Stem Auger
Driving Weight:

Logged
By: KTM
Depth
(Feet)
Lith-
ology
Material Description T o u
w
A
E
R
Samples
Laboratory Tests
Blows
per
6 in.

C
r
e
B
I
k
Moisture
Content
(0/0)
Dry
Density
(pcf)
Other
Lab
Tests
0 —I:j:.
—I
—
,;',),1!`:,1:;:',

is r; j:i
°'`"1° °'i:
: ..�: °.

I I; : t r. ] ::
°1 :r b i {:

I.;i:i: rr..

EOLIAN DEPOSITS (Qe)
fine-grained sand.
-dense, fine-grained
-grained sand.
7 1 97
MA
Sand with Silt (SP-SM): Gray, dry, loose,
@2': Becomes medium -dense.
—
'
Sand (SP): Gray to off-white, dry, medium
sand.
@7.5': Becomes gray with fine- to medium
V
10 —
—
15 —
20 -
25 -
30 -
Total Depth= 10'
No groundwater encountered
Perc test installed within boring utilizing a 2" perforated pipe and gravel.

PLATE A-4
Petra Geosciences, Inc.
447

APPENDIX B

LABORATORY TEST PROCEDURES

LABORATORY DATA SUMMARY
PETRAS 448
GEOSCIENCE^
Sot ID AS A ROCK

� PETRA

SOLID AS A ROCK
ENGINEERS + GEOLOGISTS + ENVIRONMENTAL SCIENTISTS

LABORATORY TESTING
Associated with the subsurface exploration was the collection of bulk and relatively undisturbed samples of soil materials for laboratory testing. The relatively undisturbed samples were obtained using a 2.4 -inch, outside -diameter, modified California split -spoon soil sampler lined with 1 -inch -high stainless -steel rings.

The driven ring samples were placed in sealed containers and transported to our laboratory located at 1251 W. Pomona Road, Unit #103, Corona, CA 92882, for testing.

Our laboratory testing capabilities include Soil Classifications, Moisture Content and In -Situ Moisture Content and Dry Unit Weight, Grain Size Distribution, Remolded Direct Shear, Consolidation; all in accordance with the latest procedures of American Society for Testing and Materials (ASTM) and California Department of Transportation (Caltrans).

To evaluate the engineering properties of site soils, laboratory testing was performed on selected samples of soil considered representative of those encountered. Appropriate tests were assigned by the project engineer and geologist based on project plans and specifications including the level of anticipated loads, when available, and subsurface stratigraphy. Test results were reviewed by the laboratory manager and engineer -in -charge of the laboratory or his qualified designee for completeness and accuracy. A description of laboratory test procedures and summaries of the test data are presented in the following pages.

Offices Strategically Positioned Throughout Southern California

LABORATORY
1251 W. Pomona Road, Unit #103, Corona, CA 92882 449
T: 714.549.8921 F: 951.737.3199
For more information visit us online at www.oetra-inc.com

LABORATORY TEST PROCEDURES
Soil Classification
Soil materials encountered within the property were classified and described in accordance with the Unified Soil Classification System and in general accordance with the current version of Test Method ASTM D 2488. The assigned group symbols are presented in the exploration logs, Appendix A.

Moisture Content and In Situ Moisture Content and Dry Unit Weight Moisture content of selected bulk samples and in- place moisture content and dry unit weight of selected, relatively undisturbed soil samples were determined in accordance with the current version of Test Method ASTM D 2435 and Test Method ASTM D 2216, respectively. Test data are presented in the exploration logs, Appendix A.

Laboratory Maximum Dry Unit Weight and Optimum Moisture Content The maximum dry unit weight and optimum moisture content of the on -site soils were determined for selected bulk samples in accordance with current version of Method A of ASTM D 1557. The result of this test is presented on Plate B-1.

Corrosivity Screening
Chemical and electrical analyses were performed on selected bulk samples of onsite soils to determine their soluble sulfate content, chloride content, pH (acidity) and minimum electrical resistivity. These tests were performed in accordance with the current versions of California Test Method Nos. CTM 417 (sulfate), CTM 422 (chloride), and CTM 643 (pH and resistivity) respectively. The results of these tests are included on Plate B-1.

Direct Shear
The Coulomb shear strength parameters, i.e., angle of internal friction and cohesion, were determined for selected, relatively undisturbed and/or reconstituted -bulk samples of onsite soil. This test was performed in general accordance with the current version of Test Method ASTM D 3080. Three specimens were prepared for each test. The test specimens were inundated and then sheared under various normal loads at a constant strain rate of 0.005 inch per minute. The results of the direct shear test are graphically presented on Plate B-2.

Grain Size Distribution
Grain size analysis was performed on selected bulk samples of onsite soils in accordance with the latest versions of Test Method ASTM D 136 and/or ASTM C 117, or Test Method ASTM D 422 and/or ASTM D 6913. The test result is graphically presented on Plate B-3.

Single -Point Collapse
Volume change (collapse) characteristics of selected undisturbed soil samples were determined by one- dimensional single -point collapse test. This test was performed in general accordance with the latest version of the Test Method ASTM D 5333. Axial loads were applied to laterally restrained 1 -inch -high samples.

The resulting deformation was recorded at selected time intervals. At a load approximately corresponding to the existing overburden pressure or the anticipated future load, the test samples were inundated in order to evaluate the effect of an increase in moisture content, e.g., hydro -consolidation potential (or heave). The results of this test are graphically presented on Plate B-4.

PETRA GEOSCIENCES, INC.

J.N. 24-112
Laboratory 4( 0251 W. Pomona Road, Unit 103, Corona, CA, 92882

LABORATORY DATA SUMMARY
Boring/
Test Pit/
Sample/
Number
Sample
Depth
ft.
( )
Soil/
Bedrock
Description'
p
Compaction'
Corrosivity Screening
Expansion°
Maximum
D ry
Unit Weight
(pcf)
Optimum
Moisture
(%)
Soluble
Sulfate
Content3
(%)
Chloride
Content4
(ppm)
p HS
(Acidity)
Minimum
Resistivity'
(Ohm -cm)
Index
Potential
B-1
0-5
SP
115.5

11.5 0.0018
330

7.5 20,000
-0
Very Low
,
,
Test Procedures: ' Per Test Method ASTM D 2488
2 Per Test Method ASTM D 1557
3 Per California Test Method CTM 417
4 Per California Test Method CTM 422
5 Per California Test Method CTM 643
6 Per Test Method ASTM C 117
PETRA GEOSCIENCES, INC.

J.N. 24-112
Laboratory 4511251 W. Pomona Road, Unit 103, Corona, CA, 92882 v Plate B-1

Phone #. 714.549.8921
N
CO
00 N
0)
CO
U
ns
0 0
U
M
4 ca
0 co
0 E
0 d
L
-9 a)
o
c0 N
J
Fail.

Ult.
'
C, ksf

0.000

0.102
'.-
f, deg

30.09 26.39
Tan(f)

0.58 0.50
Ult. Stress, ksf -
Fail. Stress, ksf -
O �
0 1 2 3 4 5 6
Normal Stress, ksf
Shear Stress, ksf
O N
O Cn (P N (T W
Sample No. 1 2 3
Water Content, % 11.5 11.5 11.5
Dry Density, pcf 103.4 103.5 103.5
m
Saturation, % 50.8 50.8 50.9
3 Void Ratio 0.5994 0.5990 0.5979
Diameter, in. 2.416 2.416 2.416
Height, in. 1.001 1.000 1.000
At Test
Water Content, % 20.5 20.3 19.8
Dry Density, pcf 104.6 105.9 107.3
/y--
2 Saturation, % 93.3 95.9 96.9
Void Ratio 0.5820 0.5617 0.5424
Diameter, in. 2.416 2.416 2.416
,,
9 Height, in. 0.990 0.977 0.965
Normal Stress, ksf 1.000 2.000 4.000
Fail. Stress, ksf 0.600 1.128 2.328
0 5 10 15 20
Strain, %
Strain, % 4.2 5.6 5.6
Ult. Stress, ksf 0.600 1.092 2.088
Strain, % 8.7 10.4 10.4
Strain rate, in./min. 0.040 0.040 0.040
Sample Type: Remolded
Description: Gray Fine to Medium Sand
Specific Gravity= 2.65
Remarks:

Figure B-2
Client:

Project:

Source of Sample: 24L130 Depth: 0-5
Sample Number: B-1
Proj. No.: 24-112 Date Sampled:
0 PETRA
ososCIENCEs'''
Tested By: DI
452

rn
CO
O)
0 o
CL
N
00 CO
N
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as
U
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o
o
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D
ctS
o
m
o
E
o
o_
0 0
m �
o
0u�
m
J
Particle Size Distribution Report
c. 0 S
F c
0 0 0 0 0 a
100
90 •
80 r
i
i
70 W
f
11 11
II
II
II
1 1
II
I
1 1
1 1
I
I
I
I
I
I
I
1 1 1 1
I I I
1 1
1 1

1 1
60 z
i
I'
i
I
I
Z 50
W
U
iY
W 40
�.

I
I
II
i
l
i I
I
i
I
I
1 i
•
i
I
i
I
i
i
I.
i
30 i
i
i
r
20 I
I 1
I
i
I
1 10
o
i
r

•
100 10 1
o.1
o.01 o.00l
GRAIN SIZE - mm.
+3"
% Coarse
% Gravel
% Sand
% Fines
Fine
Coarse
Medium
Fine
Silt Clay

0.0 0.0

50.4 44.1

5.5 SIEVE

PERCENT
SPEC.*
PASS?
Soil Description
SIZE
FINER

PERCENT
(X=NO)
Gray Fine to Medium Sand
3 2

1.5 1
100.0
100.0
100.0
100.0
Atterberg Limits
75 .375
100.0
100.0
PL= LL= PI=
Coefficients
#4
#10
#20
#40
100.0
100.0

89.8 49.6
D90= 0.8599 D85= 0.7714 D60= 0.5156
D50= 0.4286 D30= 0.1956 D15= 0.1132
D10= 0.0922 Cu- 5.59 Cc= 0.81
Classification
#60
#100
#140

35.8 22.8

13.3 USCS= AASHTO=
Remarks
#200

5.5 (no specification provided)
Source of Sample: 24L130 Depth: 9
Sample Number: P-1 Date: 7/19/2024
--i--
PETRA
GEOSCIENCES'c
Client:

Project:

Project No: 24-112 Figure B-3
Tested By: DI
453

N
co
N-
4)
C
O
L
CO
N
CO
N
C)
f0
U
C
O
`O
0 C
0 O
tY
0 C
O
E
O
0 o
o
�1.O
J 1-

COLLAPSE TEST REPORT
-0.5
-0.2

0.1 0.4

0.7 .Fa
Water
Added
Percent Stn
N N
(T1 N CO O) W O

0.1 1
Applied Pressure - ksf
Natural
Dry Dens.
(pcf)
LL
PI
Sp.

Gr.

Overburden
(ksf)
P c
(ksf)
C c
C r
Swell Press.
(ksf)
Clpse.
%
e o
Sat.

Moist.

2.5 °/0

0.7 %
129.8

2.65 0.3

0.737

MATERIAL DESCRIPTION
USCS
AASHTO
Gray Fine to Medium Sand
Project No. 24-112 Client:

Project:

Source of Sample: 24L130 Depth: 7.5 Sample Number: B-1
Remarks:

Figure B-4
c�
Tested By: DI
454

APPENDIX C

SEISMIC HAZARD ANALYSIS
0 PETRAES 455
GEOSCIENC ^

ke PETRA

GEOSCIENCE

SITE CLASSIFICATION DETERMINATION BASED ON BLOW COUNT, N-SPT, FOR SEISMIC DESIGN Per Table 20.3-1 and Section 20.4.2 of ASCE 7-16
J.N: 24-112
Boring: B-1
Project:

National Core Apartments
Total Depth of Boring: 65 feet
Layer
No.
(i)
Depth to Soil/Rock Layer
Layer
Thickness
(d,)
n
1 di
i=i
Mod. Cal.

Sampler Blow
Counts'
Equivalent N-
SPT2
(N;)
s
N-SPT
(N)
n
di
i=1 Ni
Top
Bottom
ft
ft
ft
ft
blows/ft
blows/ft
blows/ft
1 0

2.5 2.5

2.5 21
14 0.18
2 2.5
5 2.5

5.0 21
14 0.36
3 5

7.5 2.5

7.5 13
8 0.67
4 7.5
10 2.5

10.0 23
15 0.84
5 10
15 5

15.0 53
35 0.98
6 15
20 5

20.0 66
43 1.10
7 20
25 5

25.0 0
34 1.24
8 25
30 5

30.0 0
37 1.38
9 30
35 5

35.0 0
47 1.48
10 35
40 5

40.0 0
33 1.64
11 40
45 5

45.0 0
23 1.85
12 45
50 5

50.0 0
43 1.97
13 50
55 5

55.0 0
41 2.09
14 55
60 5

60.0 0
16 2.40
15 60
65 5

65.0 0
62 2.48
Date: 7/20/2024
SPT Test Interval: every
5 feet
Average Field Standard
Site Classification
Penetration Resistance
(blows/ft)
Per Table 20.3-1
— n
N = i=1 d` -
26 D
Ni
Li=1 Ni
1 Modified California sampler blow counts as directly measured in the field without corrections. 2 Equivalent SPT blow counts are calculated from field measured Modified California sampler blow counts using the standard Burmister formula (Burmister, 1948).

Eq. N-SPT = 0.651 x (Mod. Cal. Sampler Blow Counts)
3 Standard penetration resistance (ASTM D1586) not to exceed 100 blows /ft (305 blows /m) as directly measured in the field without corrections. When Refusal is met for a rock layer, this value shall be taken as 100 blows /ft (305 blows /m). 456

U.S. Seismic Design Maps
https://www.seismicmaps.org/
USGS web services were down for some period of time and as a result this tool wasn't operational, resulting in timeout error.

USGS web services are now operational so this tool should work as expected. 24-112 National Core Apartments
Latitude, Longitude: 33.796486, -116.394338
Victory Ln
Key Largo Ave
Nova Ln
Goggle
•
OSHPD
alAV Aa1011.10[Al
Map data O2024
Date
Design Code Reference Document
Risk Category
Site Class
7/21/2024, 11:06:57 PM
ASCE7-16
II
D - Stiff Soil
Type Value Description
Ss 1.819 MCER ground motion. (for 0.2 second period)
S1 0.757 MCER ground motion. (for 1.0s period)
SMs 1.819 Site -modified spectral acceleration value
SM1 null -See Section 11.4.8 Site -modified spectral acceleration value SDS 1.213 Numeric seismic design value at 0.2 second SA SD1 null -See Section 11.4.8 Numeric seismic design value at 1.0 second SA Type Value Description
SDC null -See Section 11.4.8 Seismic design category
Fa 1 Site amplification factor at 0.2 second
Fv null -See Section 11.4.8 Site amplification factor at 1.0 second PGA 0.789 MCEG peak ground acceleration
FPGA 1.1 Site amplification factor at PGA
PGAM 0.868 Site modified peak ground acceleration
T� 8 Long -period transition period in seconds
SsRT 2.146 Probabilistic risk -targeted ground motion. (0.2 second) SsUH 2.404 Factored uniform -hazard (2% probability of exceedance in 50 years) spectral acceleration SsD 1.819 Factored deterministic acceleration value. (0.2 second) S1 RT 0.846 Probabilistic risk -targeted ground motion. (1.0 second) S1 UH 0.963 Factored uniform -hazard (2% probability of exceedance in 50 years) spectral acceleration. 457
1 of 3 7/21/2024, 23:07

U.S. Seismic Design Maps https://www.seismicmaps.org/
Type Value Description
S1 D 0.757 Factored deterministic acceleration value. (1.0 second) PGAd 0.789 Factored deterministic acceleration value. (Peak Ground Acceleration) PGAuH 0.941 Uniform -hazard (2% probability of exceedance in 50 years) Peak Ground Acceleration CRS 0.893 Mapped value of the risk coefficient at short periods CR1 0.879 Mapped value of the risk coefficient at a period of 1 s Cv 1.464 Vertical coefficient
458
2 of 3 7/21/2024, 23:07

U.S. Seismic Design Maps https://www.seismicmaps.org/

DISCLAIMER
While the information presented on this website is believed to be correct, SEAOC /OSHPD and its sponsors and contributors assume no responsibility or liability for its accuracy. The material presented in this web application should not be used or relied upon for any specific application without competent examination and verification of its accuracy, suitability and applicability by engineers or other licensed professionals. SEAOC / OSHPD do not intend that the use of this information replace the sound judgment of such competent professionals, having experience and knowledge in the field of practice, nor to substitute for the standard of care required of such professionals in interpreting and applying the results of the seismic data provided by this website. Users of the information from this website assume all liability arising from such use. Use of the output of this website does not imply approval by the governing building code bodies responsible for building code approval and interpretation for the building site described by latitude/longitude location in the search results of this website. 459
3 of 3 7/21/2024, 23:07

Unified Hazard Tool
U.S. Geological Survey- Earthquake Hazards Program
Unified Hazard Tool
https://earthquake.usgs.gov/hazards/interactive/
Please do not use this tool to obtain ground motion parameter values for the design code reference documents covered by the U.S. Seismic Design Maps web tools (e.g., the International Building Code and the ASCE 7 or 41 Standard). The values returned by the two applications are not identical.

Please also see the new USGS Earthquake Hazard Toolbox for access to the most recent NSHMs for the conterminous U.S. and Hawaii.
^ Input
Edition
Dynamic: Conterminous U.S. 2014 (...

Latitude
Decimal degrees

33.796486
Spectral Period
Peak Ground Acceleration
Time Horizon
Return period in years
2475
Longitude
Decimal degrees, negative values for western longitudes -116.394338
Site Class
259 m,/s (Site class D)
460
l of 5 7/21/2024, 23:05

Unified Hazard Tool
https://earthquake.usgs.gov/hazards/interactive/
^ Hazard Curve
Annual Frequency of Exceedence
Annual Frequency of Exceedence
le+0
le -1
1e-2
le -3
le -4
le -5
le -6
le -7
le -8
le -9
1e+0
le -1
le -2
le -3
le -4
le -5
le -6
le -7
le -8
Hazard Curves
- Time Horizon 2475 years
- Peak Ground Acceleration
- e- 0.10 Second Spectral Acceleration
- 0- - 0.20 Second Spectral Acceleration
-►- 0.30 Second Spectral Acceleration
- 0- 0.50 Second Spectral Acceleration
-y- 0.75 Second Spectral Acceleration
- 6- 1.00 Second Spectral Acceleration
- 2.00 Second Spectral Acceleration
z- 3.00 Second Spectral Acceleration
0- 4.00 Second Spectral Acceleration
- 8- 5.00 Second Spectral Acceleration
le -2 le -1 1e+0
Ground Motion (g)
Component Curves for Peak Ground Acceleration
— Time Horizon 2475 years
+ System
rt- Grid
— 0— Interface
— 8— Fault
le -2 le -1 1e+0
Ground Motion (g)
View Raw Data
Ground Motion (g)

3.5 3.0

2.5 2.0

1.5 1.0

0.5 0.0
Uniform Hazard Response Spectrum
Spectral Period (s): PGA
Ground Motion (g): 0.9444

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5
Spectral Period (s)
461
2 of 5 7/21/2024, 23:05

Unified Hazard Tool
https://earthquake.usgs.gov/hazards/interactive/
Deaggregation
Component
Total
N
12 fo
N
z
0 -o
0 U
A•
S
1S
..•
C(..ses `o�
d t)ce 4S
rR0,0('�J SS
S
;/-5'
S.
••♦
•
•
6S
?S
CIOse SS
3S 4/7
4S rR4p (z.

4. ••.
•
55 •
6S
65 ▪ E = (-°° .. -2.5)
▪ E = [-2.5 .. -2)
▪ E _ [-2 .. -1.5)
▪ E _ [-1.5 .. -1)
❑ E _ [-1 .. -0.5)
❑ E _ [-0.5 .. 0)
❑ E=[0..0.5)
• E=[0.5..1)
▪ E _ [1 .. 1.5)
• E _ [1.5 .. 2)
▪ E=[2..2.5)
▪ E=[2.5..+co)
3 of 5
462
7/21/2024, 23:05

Unified Hazard Tool https://earthquake.usgs.gov/hazards/interactive/ Summary statistics for, Deaggregation: Total
Deaggregation targets Recovered targets
Return period: 2475 yrs
Exceedance rate: 0.0004040404 yr'
PGA ground motion: 0.94442438 g
Return period: 3248.499 yrs
Exceedance rate: 0.00030783448 yr
1 Totals Mean (over all sources)
Binned: 100 0/0
Residual: 0 0/0
Trace: 0.06 %
m: 7.21
r: 7.52 km
Eo: 1.58 o
Mode (largest m -r bin) Mode (largest m-r-Eo bin)
m: 7.49
r: 6.65 km
Eo: 1.5
Contribution: 16.34 0/0
Discretization
r: min = 0.0, max =1000.O,A=20.Okm
m: min = 4.4, max = 9.4, A = 0.2
E: min= -3.0, max = 3.0, A= 0.5
m: 7.49
r: 6.61 km
Eo: 1.39 a
Contribution: 11.82 0/0
Epsilon keys
E0: .. -2.5)
El: [-2.5 .. -2.0)
E2: [-2.0 .. -1.5)
E3: [-1.5 .. -1.0)
E4: [-1.0 .. -0.5)
E5: [-0.5 .. 0.0)
E6: [0.0 .. 0.5)
E7: [0.5 .. 1.0)
E8: [1.0 .. 1.5)
E9: [1.5 .. 2.0)
E10: [2.0 .. 2.5)
Ell: [2.5 .. +.0]
463
4 of 5 7/21/2024, 23:05

Unified Hazard Tool https://earthquake.usgs.gov/hazards/interactive/ Deaggregation Contributors
Source Set L, Source
UC33brAvg_FM31
San Andreas (San Gorgonio Pass -Garnet Hlll) [1]
San Andreas (North Branch Mill Creek) [10]
UC33brAvg_FM32
San Andreas (San Gorgonio Pass -Garnet HIII) [1]
San Andreas (North Branch Mill Creek) [10]
UC33brAvg_FM31 (opt)
PointSourceFinite: -116.394, 33.801
PointSourceFinite: -116.394, 33.801
UC33brAvg_FM32 (opt)
PointSourceFinite: -116.394, 33.801
PointSourceFinite: -116.394, 33.801
Type r m £o ton lat az
System 38.53

6.54 7.61 1.48 116.358°W 33.846°N 31.71 31.12

8.28 7.88 1.31 116.344°W 33.853°N 36.36 3.95
System
Grid
Grid

38.48 6.54 7.60 1.48 116.358°W 33.846°N 31.71 30.96

8.28 7.85 1.32 116.344°W 33.853°N 36.36 4.16

11.50 4.92 5.66 1.60 116.394°W 33.801°N 0.00 3.82

4.92 5.66 1.60 116.394°W 33.801°N 0.00 3.82

11.49 4.92 5.66 1.60 116.394°W 33.801°N 0.00 3.82

4.92 5.66 1.60 116.394°W 33.801°N 0.00 3.82
464
5 of 5 7/21/2024, 23:05

*** Deaggregation of Seismic Hazard at One Period of Spectral Acceleration *** *** Data from Dynamic: Conterminous U.S. 2014 (update) (unknown) **** PSHA Deaggregation. %contributions.
site: Test
longitude: 116.394°W
latitude: 33.796°E
imt: Peak Ground Acceleration
vs30 = 259 m/s (Site class D)
return period: 2475 yrs.
#This deaggregation corresponds to: Total
Summary statistics for PSHA PGA deaggregation, r=distance, E=epsilon:

Deaggregation targets:

Return period: 2475 yrs
Exceedance rate: 0.0004040404 yr-1
PGA ground motion: 0.94442438 g
Recovered targets:

Return period: 3248.499 yrs
Exceedance rate: 0.00030783448 yr-1
Totals:

Binned: 100 %
Residual: 0 %
Trace: 0.06 %
Mean (over all sources):
m: 7.21
r: 7.52 km
co: 1.58 a
Mode (largest m -r bin):
m: 7.49
r: 6.65 km
Ea: 1.5 a
Contribution: 16.34 %
Mode (largest m -r -E0 bin):
m: 7.49
r: 6.61 km
Eo: 1.39 a
Contribution: 11.82 %
Discretization:
r: min = 0.0, max = 1000.0, A = 20.0 km
m: min = 4.4, max = 9.4, A = 0.2
E: min = -3.0, max = 3.0, A = 0.5 a
Epsilon keys:

EO: [-° .. -2.5)
E1: [-2.5 .. -2.0)
E2: [-2.0 .. -1.5)
E3: [-1.5 .. -1.0)
E4: [-1.0 .. -0.5)
E5: [-0.5 .. 0.0)
E6: [0.0 .. 0.5)
E7: [0.5 .. 1.0)
E8: [1.0 .. 1.5)
E9: [1.5 .. 2.0)
E10: [2.0 .. 2.5)
E11: [2.5 .. +°°]
Closest Distance, rRup (km) Magnitude (Mw) ALLE E=(-oo,-2.5) E=[-2.5,-2) E=[-2,-1.5) E=[-1.5,-1) E=[-1,-0.5) E=[-0.5,0) E=[0,0.5) E=[0.5,1) €=[1,1.5) E=[1.5,2) E=[2,2.5) E=[2.5,-)
70 8.1 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 70 8.3 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 50 7.5 0.000 .0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 50 7.7 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 50 7.9 0.015 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.015 50 8.1 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 50 8.3 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.001 0.005 30 6.1 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 30 6.3 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 30 6.5 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 30 6.7 0.011 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.002 0.009 30 6.9 0.016 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.002 0.014 30 7.1 0.052 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.003 0.049 465

30 7.3 0.058 0.000 0.000
30 7.5 0.111 0.000 0.000
30 7.7 0.143 0.000 0.000
30 7.9 0.418 0.000 0.000
30 8.1 0.749 0.000 0.000
30 8.3 0.466 0.000 0.000
10 5.1 2.816 0.000 0.000
10 5.3 3.142 0.000 0.000
10 5.5 3.553 0.000 0.000
10 5.7 3.036 0.000 0.000
10 5.9 2.387 0.000 0.000
10 6.1 2.727 0.000 0.000
10 6.3 2.847 0.000 0.000
10 6.5 3.811 0.000 0.000
10 6.7 1.333 0.000 0.000
10 6.9 1.699 0.000 0.000
10 7.1 1.569 0.000 0.000
10 7.3 15.066 0.000 0.000
10 7.5 16.336 0.000 0.000
10 7.7 13.058 0.000 0.000
10 7.9 7.180 0.000 0.000
10 8.1 13.116 0.000 0.000
10 8.3 4.263 0.000 0.000
Principal Sources (faults,
UC33brAvg_FM31:

Percent Contributed: 38.53
Distance (km): 7.7522696
Magnitude: 7.6290489
Epsilon (mean values): 1.5183046
San Andreas (San Gorgonio Pass -Garnet Hill) [1] :

Percent Contributed: 31.12
Distance (km): 6.5353046
Magnitude: 7.6050927
Epsilon (mean values): 1.4767216
Azimuth: 31.71136
Latitude: 33.845511
Longitude: -116.35786
San Andreas (North Branch Mill Creek) [10]:

Percent Contributed: 3.95
Distance (km): 8.2781536
Magnitude: 7.8816596
Epsilon (mean values): 1.3120476
Azimuth: 36.358309
Latitude: 33.853076
Longitude: -116.34417
UC33brAvg_FM32:

Percent Contributed: 38.48
Distance (km): 7.7441979
Magnitude: 7.6245993
Epsilon (mean values): 1.5185216
San Andreas (San Gorgonio Pass -Garnet HI11) [1] :

Percent Contributed: 30.96
Distance (km): 6.5353046
Magnitude: 7.6018745
Epsilon (mean values): 1.478169
Azimuth: 31.71136
Latitude: 33.845511
Longitude: -116.35786
San Andreas (North Branch Mill Creek) [10]:

Percent Contributed: 4.16
Distance (km): 8.2781536
Magnitude: 7.8512625
Epsilon (mean values): 1.3196983
Azimuth: 36.358309
Latitude: 33.853076
Longitude: -116.34417
UC33brAvg_FM31 (opt):

Percent Contributed: 11.5
Distance (km): 6.7410744
Magnitude: 5.807404

0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000

0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.003

0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.002

0.000 0.000 0.000 0.000 0.000 0.000 0.000 1.104

0.000 0.000 0.000 0.000 0.000 0.000 0.000 2.397

0.000 0.000 0.000 0.000 0.000 0.000 1.763 1.059

0.000 0.000 0.000 0.000 0.000 0.000 1.399 0.866

0.000 0.000 0.000 0.000 0.000 0.000 0.993 0.677

0.000 0.000 0.000 0.000 0.000 0.000 0.662 1.011

0.000 0.000 0.000 0.000 0.000 0.000 0.429 1.544

0.000 0.000 0.000 0.000 0.000 0.034 0.403 2.063

0.000 0.000 0.000 0.000 0.000 0.065 0.237 0.805

0.000 0.000 0.000 0.000 0.000 0.057 0.136 1.204

0.000 0.000 0.000 0.000 0.000 0.042 0.310 0.618

0.000 0.000 0.000 0.000 0.000 0.022 9.549 3.804

0.000 0.000 0.000 0.000 0.000 0.006 11.818 3.664

0.000 0.000 0.000 0.000 0.000 0.001 9.799 2.633

0.000 0.000 0.000 0.000 0.000 0.001 5.286 1.523

0.000 0.000 0.000 0.000 0.000 0.012 9.984 2.531

0.000 0.000 0.000 0.000 0.000 0.495 2.796 0.795
subduction, random seismicity having > 3% contribution

0.004

0.013

0.018

0.166

0.493

0.375

1.403

0.289

0.256

0.398

0.475

0.877

0.744

0.749

0.176

0.264

0.518

1.666

0.848

0.625

0.368

0.589

0.177

0.054

0.099

0.125

0.252

0.253

0.089

0.309

0.456

0.474

0.372

0.242

0.177

0.130

0.562

0.051

0.039

0.080

0.025

0.001

0.000

0.002

0.001

0.000
466

Epsilon (mean values): 1.8045724
PointSourceFinite: -116.394, 33.801:

Percent Contributed: 3.82
Distance (km): 4.9165462
Magnitude: 5.6568818
Epsilon (mean values): 1.5987339
Azimuth: 0
Latitude: 33.800983
Longitude: -116.39434
PointSourceFinite: -116.394, 33.801:

Percent Contributed: 3.82
Distance (km): 4.9165462
Magnitude: 5.6568818
Epsilon (mean values): 1.5987339
Azimuth: 0
Latitude: 33.800983
Longitude: -116.39434
UC33brAvg_FM32 (opt):

Percent Contributed: 11.49
Distance (km): 6.740285
Magnitude: 5.806952
Epsilon (mean values): 1.8046318
PointSourceFinite: -116.394, 33.801:

Percent Contributed: 3.82
Distance (km): 4.9166413
Magnitude: 5.6565838
Epsilon (mean values): 1.5988436
Azimuth: 0
Latitude: 33.800983
Longitude: -116.39434
PointSourceFinite: -116.394, 33.801:

Percent Contributed: 3.82
Distance (km): 4.9166413
Magnitude: 5.6565838
Epsilon (mean values): 1.5988.436
Azimuth: 0
Latitude: 33.800983
Longitude: -116.39434
PSHA Deaggregation. %contributions.
site: Test
longitude: 116.394°W
latitude: 33.796°E
imt: Peak Ground Acceleration
vs30 = 259 m/s (Site class D)
return period: 2475 yrs.
#This deaggregation corresponds to: GMM: Abrahamson, Silva & Kamai (2014) Summary statistics for PSHA PGA deaggregation, r=distance, s=epsilon:

Deaggregation targets:

Return period: 2475 yrs
Exceedance rate: 0.0004040404 yr-1
PGA ground motion: 0.94442438 g
Recovered targets:

Return period: 3248.499 yrs
Exceedance rate: 0.00030783448 yr-1
Totals:

Binned: 22.08
Residual: 0 %
Trace: 0.05 %
Mean (over all sources):
m: 7.11
r: 7.89 km
co: 1.82 a
Mode (largest m -r bin):
m: 7.49
r: 6.64 km
€o: 1.67 o
Contribution: 3.51 0
Mode (largest m -r -co bin):
m: 7.49
r: 6.61 km
467

co: 1.67 a
Contribution: 3.49 %
Discretization:
r: min = 0.0, max = 1000.0, A = 20.0 km
m: min = 4.4, max = 9.4, A = 0.2
E: min = -3.0, max = 3.0, A = 0.5 a
Epsilon keys:

E0: [-° .. -2.5)
E1: [-2.5 .. -2.0)
E2: [-2.0 .. -1.5)
E3: [-1.5 .. -1.0)
E4: [-1.0 .. -0.5)
c5: [-0.5 .. 0.0)
E6: [0.0 .. 0.5)
E7: [0.5 .. 1.0)
E8: [1.0 .. 1.5)
E9: [1.5 .. 2.0)
E10: [2.0 .. 2.5)
E11: [2.5 .. +-]
Closest Distance, rRup (km) Magnitude (Mw) ALLE €=(-oo,-2.5) E=[-2.5,-2) E=[-2,-1.5) E=[-1.5,-1) E=[-1,-0.5) E=[-0.5,0) E=[0,0.5) E=[0.5,1) E=[1,1.5) E=[1.5,2) E=[2,2.5) E=[2.5,00)
70 8.1 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 70 8.3 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 50 7.7 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 50 7.9 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 50 8.1 0.002 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.002 50 8.3 0.002 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.002 30 6.3 0.001 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.001 30 6.5 0.001 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.001 30 6.7 0.002 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.002 30 6.9 0.004 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.004 30 7.1 0.016 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.016 30 7.3 0.018 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.018 30 7.5 0.036 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.036 30 7.7 0.050 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.003 0.047 30 7.9 0.133 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.033 0.100 30 8.1 0.241 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.110 0.130 30 8.3 0.148 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.148 0.000 10 5.1 1.167 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.568 0.338 0.261 10 5.3 0.920 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.681 0.000 0.239 10 5.5 0.731 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.516 0.038 0.178 10 5.7 0.608 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.412 0.067 0.130 10 5.9 0.491 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.318 0.084 0.089 10 6.1 0.604 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.255 0.290 0.059 10 6.3 0.667 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.305 0.329 0.033 10 6.5 1.002 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.081 0.507 0.121 0.293 10 6.7 0.318 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.070 0.178 0.053 0.018 10 6.9 0.398 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.039 0.287 0.053 0.019 10 7.1 0.380 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.018 0.205 0.143 0.014 10 7.3 3.373 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.007 3.058 0.308 0.000 10 7.5 3.506 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.002 3.493 0.011 0.000 10 7.7 2.621 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 2.618 0.003 0.000 10 7.9 1.386 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 1.356 0.030 0.000 10 8.1 2.466 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 2.453 0.013 0.000 10 8.3 0.783 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.783 0.000 0.000 Principal Sources (faults, subduction, random seismicity having > 3% contribution UC33brAvg_FM31:

Percent Contributed: 8.17
Distance (km): 8.1838797
Magnitude: 7.5998188
Epsilon (mean values): 1.7365455
San Andreas (San Gorgonio Pass -Garnet HI11) [1] :

Percent Contributed: 6.58
Distance (km): 6.5353046
Magnitude: 7.5831569
Epsilon (mean values): 1.661708
Azimuth: 31.71136
Latitude: 33.845511
Longitude: -116.35786
468

UC33brAvg_FM32:

Percent Contributed: 8.14
Distance (km): 8.1708632
Magnitude: 7.5947826
Epsilon (mean values): 1.7381942
San Andreas (San Gorgonio Pass -Garnet Hill) [1] :

Percent Contributed: 6.54
Distance (km): 6.5353046
Magnitude: 7.5792035
Epsilon (mean values): 1.6632409
Azimuth: 31.71136
Latitude: 33.845511
Longitude: -116.35786
UC33brAvg FM31 (opt):

Percent Contributed: 2.89
Distance (km): 7.0774363
Magnitude: 5.730687
Epsilon (mean values): 2.051394
UC33brAvg_FM32 (opt):

Percent Contributed: 2.89
Distance (km): 7.076764
Magnitude: 5.7302345
Epsilon (mean values): 2.0514829
PSHA Deaggregation. °contributions
site: Test
longitude: 116.394°W
latitude: 33.796°E
imt: Peak Ground Acceleration
vs30 = 259 m/s (Site class D)
return period: 2475 yrs.
#This deaggregation corresponds to: GMM: Boore, Stewart, Seyhan & Atkinson (2014) Summary statistics for PSHA PGA deaggregation, r=distance, €=epsilon:

Deaggregation targets:

Return period: 2475 yrs
Exceedance rate: 0.0004040404 yr-'
PGA ground motion: 0.94442438 g
Recovered targets:

Return period: 3248.499 yrs
Exceedance rate: 0.00030783448 yr-'
Totals:

Binned: 43.34 %
Residual: 0 %
Trace: 0.09 %
Mean (over all sources):
m: 7.14
r: 7.7 km
co: 1.45 a
Mode (largest m -r bin):
m: 7.49
r: 6.69 km
€o: 1.37 a
Contribution: 6.38
Mode (largest m -r -£o bin):
m: 7.49
r: 6.65 km
co: 1.36
Contribution: 6.35 %
Discretization:
r: min = 0.0, max = 1000.0, A = 20.0 km
m: min = 4.4, max = 9.4, A = 0.2
e: min = -3.0, max = 3.0, A = 0.5 a
Epsilon keys:
e0: [-°° .. -2.5)
El: [-2.5 .. -2.0)
€2: [-2.0 .. -1.5)
€3: [-1.5 .. —1.0)
e4: [-1.0 .. —0.5)
€5: [-0.5 .. 0.0)
€6: [0.0 .. 0.5)
469

€7: [0.5 .. 1.0)
e8: [1.0 .. 1.5)
e9: [1.5 .. 2.0)
e10: [2.0 .. 2.5)
€11: [2.5 .. +-]
Closest Distance, rRup (km)
Magnitude (Mw) ALL e
€=[-1.5,-1) e=[-1,-0.5) €=[-0.5,0) e=[0,0.5)
e=[2,2.5) e=[2.5,00)
70 8.1 0.000 0.000 0.000 0.000
70 8.3 0.000 0.000 0.000 0.000
50 7.5 0.000 0.000 0.000 0.000
50 7.7 0.000 0.000 0.000 0.000
50 7.9 0.010 0.000 0.000 0.000
50 8.1 0.003 0.000 0.000 0.000
50 8.3 0.003 0.000 0.000 0.000
30 6.1 0.000 0.000 0.000 0.000
30 6.3 0.004 0.000 0.000 0.000
30 6.5 0.004 0.000 0.000 0.000
30 6.7 0.008 0.000 0.000 0.000
30 6.9 0.011 0.000 0.000 0.000
30 7.1 0.032 0.000 0.000 0.000
30 7.3 0.035 0.000 0.000 0.000
30 7.5 0.070 0.000 0.000 0.000
30 7.7 0.085 0.000 0.000 0.000
30 7.9 0.219 0.000 0.000 0.000
30 8.1 0.378 0.000 0.000 0.000
30 8.3 0.226 0.000 0.000 0.000
10 5.1 0.991 0.000 0.000 0.000
10 5.3 1.514 0.000 0.000 0.000
10 5.5 2.134 0.000 0.000 0.000
10 5.7 1.804 0.000 0.000 0.000
10 5.9 1.361 0.000 0.000 0.000
10 6.1 1.421 0.000 0.000 0.000
10 6.3 1.378 0.000 0.000 0.000
10 6.5 1.789 0.000 0.000 0.000
10 6.7 0.546 0.000 0.000 0.000
10 6.9 0.701 0.000 0.000 0.000
10 7.1 0.656 0.000 0.000 0.000
10 7.3 5.880 0.000 0.000 0.000
10 7.5 6.383 0.000 0.000 0.000
10 7.7 5.390 0.000 0.000 0.000
10 7.9 2.976 0.000 0.000 0.000
10 8.1 5.508 0.000 0.000 0.000
10 8.3 1.822 0.000 0.000 0.000

0.000

0.000
e=( -m,-2.5)
€=[0.5,1)

0.000

0.006

0.008

0.003

0.000

0.012

0.495
e=[-2.5,-2) e=[-2,-1.5)
e=[1,1.5) €=[1.5,2)

0.000

0.000
o.000

0.000

1.763

1.399

0.993

0.662

0.409

0.228

0.112

0.078

0.279

5.354

6.348

5.382

2.917

5.462

1.319

0.000 0.000 0.000

0.000 0.000 0.010

0.000 0.000 0.003

0.000 0.001 0.002

0.000 0.000 0.000

0.000 0.000 0.004

0.000 0.002 0.006

0.000 0.002 0.009

0.000 0.003 0.030

0.000 0.003 0.032

0.000 0.012 0.058

0.000 0.012 0.073

0.000 0.112 0.106

0.003 0.372 0.004

0.002 0.224 0.000

0.536 0.446 0.010

1.392 0.000 0.122

0.001 0.218 0.152

0.000 0.290 0.114

0.000 0.309 0.058

0.439 0.276 0.044

0.788 0.129 0.053

0.999 0.371 0.191

0.382 0.040 0.012

0.526 0.095 0.002

0.118 0.254 0.000

0.212 0.306 0.000

0.018 0.015 0.000

0.008 0.000 0.000

0.059 0.000 0.000

0.034 0.000 0.000

0.007 0.000 0.000
Principal Sources (faults, subduction, random seismicity having > 3% contribution UC33brAvg_FM32:

Percent Contributed: 15 91
Distance (km): 8.056292
Magnitude: 7.623832
Epsilon (mean values): 1.3878356
San Andreas (San Gorgonio Pass -Garnet HI11) [1] :

Percent Contributed: 12.14
Distance (km): 6.5353046
Magnitude: 7.6010797
Epsilon (mean values): 1.3457294
Azimuth: 31.71136
Latitude: 33.845511
Longitude: -116.35786
San Andreas (North Branch Mill Creek) [10]:

Percent Contributed: 2.13
Distance (km): 8.2781536
Magnitude: 7.8467268
Epsilon (mean values): 1.0820297
Azimuth: 36.358309
Latitude: 33.853076
Longitude: -116.34417
UC33brAvg_FM31:

Percent Contributed: 15.88
Distance (km): 8.0622881
Magnitude: 7.6287094
470

Epsilon (mean values): 1.3887459
San Andreas (San Gorgonio Pass -Garnet HI11) [1] :

Percent Contributed: 12.19
Distance (km): 6.5353046
Magnitude: 7.6037953
Epsilon (mean values): 1.3448949
Azimuth: 31.71136
Latitude: 33.845511
Longitude: -116.35786
San Andreas (North Branch Mill Creek) [10]:

Percent Contributed: 2.02
Distance (km): 8.2781536
Magnitude: 7.8788431
Epsilon (mean values): 1.0744497
Azimuth: 36.358309
Latitude: 33.853076
Longitude: -116.34417
UC33brAvg_FM31 (opt):

Percent Contributed: 5.78
Distance (km): 6.709053
Magnitude: 5.8000703
Epsilon (mean values): 1.6039007
PointSourceFinite: -116.394, 33.801:

Percent Contributed: 2.01
Distance (km): 4.9908756
Magnitude: 5.6523822
Epsilon (mean values): 1.3913807
Azimuth: 0
Latitude: 33.800983
Longitude: -116.39434
PointSourceFinite: -116.394, 33.801:

Percent Contributed: 2.01
Distance (km): 4.9908756
Magnitude: 5.6523822
Epsilon (mean values): 1.3913807
Azimuth: 0
Latitude: 33.800983
Longitude: -116.39434
UC33brAvg_FM32 (opt):

Percent Contributed: 5.78
Distance (km): 6.7081391
Magnitude: 5.7996854
Epsilon (mean values): 1.6039164
PointSourceFinite: -116.394, 33.801:

Percent Contributed: 2.01
Distance (km): 4.9908925
Magnitude: 5.6521468
Epsilon (mean values): 1.3914648
Azimuth: 0
Latitude: 33.800983
Longitude: -116.39434
PointSourceFinite: -116.394, 33.801:

Percent Contributed: 2.01
Distance (km): 4.9908925
Magnitude: 5.6521468
Epsilon (mean values): 1.3914648
Azimuth: 0
Latitude: 33.800983
Longitude: -116.39434
PSHA Deaggregation. %contributions.
site: Test
longitude: 116.394°W
latitude: 33.796°E
imt: Peak Ground Acceleration
vs30 = 259 m/s (Site class D)
return period: 2475 yrs.
#This deaggregation corresponds to: GMM: Campbell & Bozorgnia (2014) Summary statistics for PSHA PGA deaggregation, r=distance, e=epsilon:

Deaggregation targets:

Return period: 2475 yrs
471

Exceedance rate: 0.0004040404 yr-'
PGA ground motion: 0.94442438 g
Recovered targets:

Return period: 3248.499 yrs
Exceedance rate: 0.00030783448 yr-'
Totals:

Binned: 4.02 %
Residual: 0 %
Trace: 0.02 %
Mean (over all sources):
m: 7.46
r: 6.7 km
co: 2.26 a
Mode (largest m -r bin):
m: 7.49
r: 6.61 km
co: 2.25 o
Contribution: 0.81
Mode (largest m -r -co bin):
m: 7.49
r: 6.61 km
co: 2.25 a
Contribution: 0.81 %
Discretization:
r: min = 0.0, max = 1000.0, A = 20.0 km
m: min = 4.4, max = 9.4, A = 0.2
€: min = -3.0, max = 3.0, A = 0.5 a
Epsilon keys:
eO: [-OO .. —2.5)
el: [-2.5 .. —2.0)
€2: [-2.0 .. —1.5)
e3: [-1.5 .. —1.0)
e4: [-1.0 .. —0.5)
e5: [-0.5 .. 0.0)
c6: [0.0 .. 0.5)
€7: [0.5 .. 1.0)
e8: [1.0 .. 1.5)
€9: [1.5 .. 2.0)
€10: [2.0 .. 2.5)
ell: [2.5 .. +°]
Closest Distance, rRup (km) Magnitude (Mw) ALL € e=( —c°,-2.5) €=[-2.5,-2) e=[-2,-1.5) e=[-1.5,-1) e=[-1,-0.5) e=[-0.5,0) e=[0,0.5) e=[0.5,1) e=[1,1.5) €=[1.5,2) e=[2,2.5) e=[2.5,-)
30 7.3 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 30 7.5 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 30 7.7 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 30 7.9 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 30 8.1 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 30 8.3 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 10 5.3 0.003 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.003 10 5.5 0.016 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.016 10 5.7 0.026 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.026 10 5.9 0.035 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 0.029 10 6.1 0.068 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.046 0.022 10 6.3 0.135 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.108 0.027 10 6.5 0.215 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.039 0.151 0.025 10 6.7 0.089 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.027 0.053 0.009 10 6.9 0.101 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.015 0.080 0.006 10 7.1 0.065 .0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.007 0.053 0.005 10 7.3 0.748 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.003 0.723 0.022 10 7.5 0.812 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.001 0.811 0.001 10 7.7 0.619 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.619 0.000 10 7.9 0.332 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.330 0.002 10 8.1 0.578 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.576 0.001 10 8.3 0.177 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.177 0.000 Principal Sources (faults, subduction, random seismicity having > 3% contribution UC33brAvg_FM32:

Percent Contributed: 1.79
Distance (km): 6.7784225
472

Magnitude: 7.5903583
Epsilon (mean values): 2.2502599
San Andreas (San Gorgonio Pass -Garnet HI11) [1] :

Percent Contributed: 1.57
Distance (km): 6.5353046
Magnitude: 7.5636338
Epsilon (mean values): 2.2415974
Azimuth: 31.71136
Latitude: 33.845511
Longitude: -116.35786
UC33brAvg_FM31:

Percent Contributed: 1.79
Distance (km): 6.7745372
Magnitude: 7.5940581
Epsilon (mean values): 2.2503848
San Andreas (San Gorgonio Pass -Garnet HI11) [1] :

Percent Contributed: 1.58
Distance (km): 6.5353046
Magnitude: 7.567265
Epsilon (mean values): 2.2411248
Azimuth: 31.71136
Latitude: 33.845511
Longitude: -116.35786
PSHA Deaggregation. %contributions.
site: Test
longitude: 116.394°W
latitude: 33.796°E
imt: Peak Ground Acceleration
vs30 = 259 m/s (Site class D)
return period: 2475 yrs.
#This deaggregation corresponds to: GMM: Chiou & Youngs (2014) Summary statistics for PSHA PGA deaggregation, r=distance, E=epsilon:

Deaggregation targets:

Return period: 2475 yrs
Exceedance rate: 0.0004040404
PGA ground motion: 0.94442438
Recovered targets:

Return period: 3248.499 yrs
Exceedance rate: 0.00030783448 yr-'
Totals:

Binned: 30.56 %
Residual: 0 %
Trace: 0.05 %
Mean (over all sources):
m: 7.35
r: 7.1 km
co: 1.52 a
Mode (largest m -r bin):
m: 7.49
r: 6.63 km
co: 1.43 a
Contribution: 5.64
yr-'
g
Mode (largest m -r -E0 bin):
m: 7.49
r: 6.56 km
co: 1.43
Contribution: 5.47 %
Discretization:
r: min = 0.0, max = 1000.0, A = 20.0 km
m: min = 4.4, max = 9.4, A = 0.2
E: min = -3.0, max = 3.0, A = 0.5 a
Epsilon keys:

E0:

El:

E2:

E3:

E4:

E5:

E6:
[-m .. -2.5)
[-2.5 .. -2.0)
[-2.0 .. -1.5)
[-1.5 .. -1.0)
[-1.0 .. -0.5)
[-0.5 .. 0.0)
[0.0 .. 0.5)
473

€7: [0.5 .. 1.0)
e8: [1.0 .. 1.5)
e9: [1.5 .. 2.0)
E10: [2.0 .. 2.5)
€11: [2.5 .. +-]
Closest Distance, rRup (km)
Magnitude (Mw) ALL e
€=[-1.5,-1) e=[-1,—0.5) €=[-0.5,0) e=[0,0.5)
e=[2,2.5) s=[2.5,00)
50 7.7 0.000 0.000 0.000 0.000
50 7.9 0.000 0.000 0.000 0.000
50 8.1 0.000 0.000 0.000 0.000
50 8.3 0.001 0.000 0.000 0.000
30 6.7 0.001 0.000 0.000 0.000
30 6.9 0.001 0.000 0.000 0.000
30 7.1 0.004 0.000 0.000 0.000
30 7.3 0.005 0.000 0.000 0.000
30 7.5 0.005 0.000 0.000 0.000
30 7.7 0.008 0.000 0.000 0.000
30 7.9 0.067 0.000 0.000 0.000
30 8.1 0.130 0.000 0.000 0.000
30 8.3 0.091 0.000 0.000 0.000
10 5.1 0.658 0.000 0.000 0.000
10 5.3 0.704 0.000 0.000 0.000
10 5.5 0.672 0.000 0.000 0.000
10 5.7 0.598 0.000 0.000 0.000
10 5.9 0.501 0.000 0.000 0.000
10 6.1 0.634 0.000 0.000 0.000
10 6.3 0.667 0.000 0.000 0.000
10 6.5 0.805 0.000 0.000 0.000
10 6.7 0.379 0.000 0.000 0.000
10 6.9 0.499 0.000 0.000 0.000
10 7.1 0.467 0.000 0.000 0.000
10 7.3 5.065 0.000 0.000 0.000
10 7.5 5.635 0.000 0.000 0.000
10 7.7 4.429 0.000 0.000 0.000
10 7.9 2.485 0.000 0.000 0.000
10 8.1 4.565 0.000 0.000 0.000
10 8.3 1.481 0.000 0.000 0.000
Principal Sources (faults, subduction,
UC33brAvg_FM31:

Percent Contributed: 12.69
Distance (km): 7.2244671
Magnitude: 7.6532072
Epsilon (mean values): 1.4368664
San Andreas (San Gorgonio Pass -Garnet Hill) [1] :

Percent Contributed: 10.77
Distance (km): 6.5353046
Magnitude: 7.6254958
Epsilon (mean values): 1.4010122
Azimuth: 31.71136
Latitude: 33.845511
Longitude: -116.35786
San Andreas (North Branch Mill Creek) [10]:

Percent Contributed: 1.14
Distance (km): 8.2781536
Magnitude: 7.8911321
Epsilon (mean values): 1.3969631
Azimuth: 36.358309
Latitude: 33.853076
Longitude: -116.34417
UC33brAvg_FM32:

Percent Contributed: 12.65
Distance (km): 7.2138514
Magnitude: 7.6495929
Epsilon (mean values): 1.438004
San Andreas (San Gorgonio Pass -Garnet Hill) [1] :

Percent Contributed: 10.7
Distance (km): 6.5353046
Magnitude: 7.6222483
Epsilon (mean values): 1.403131

0.000 0.000 0.000

0.000 0.000 0.000
o.000 o.000 o.000

0.000 0.000 0.000

0.000 0.000 0.000
random seismicity ha
e=(--,-2.5) e=[-2.5,-2) e=[-2,-1.5)
€=[0.5,1) e=[1,1.5) €=[1.5,2)

0.000 0.000 0.000 0.000

0.000 0.000 0.000 0.324

0.000 0.000 0.000 0.543

0.000 0.000 0.000 0.454

0.000 0.000 0.000 0.359

0.000 0.000 0.000 0.317

0.000 0.000 0.020 0.452

0.000 0.034 0.093 0.518

0.000 0.065 0.055 0.218

0.000 0.057 0.019 0.376

0.000 0.036 0.013 0.289

0.000 0.015 4.187 0.531

0.000 0.004 5.468 0.153

0.000 0.000 4.417 0.008

0.000 0.000 2.369 0.107

0.000 0.000 4.521 0.044

0.000 0.000 1.477 0.005
ving > 3% contribution

0.000

0.001

0.002

0.020

0.011

0.003

0.620

0.289

0.000

0.042

0.076

0.264

0.177

0.107

0.030

0.036

0.069

0.328

0.011

0.003

0.008

0.000

0.001

0.003

0.004

0.006

0.046

0.119

0.089

0.038

0.091

0.129

0.103

0.066

0.053

0.018

0.053

0.012

0.061

0.003

0.000

0.000
474

Azimuth: 31.71136
Latitude: 33.845511
Longitude: -116.35786
San Andreas (North Branch Mill Creek) [10]:

Percent Contributed: 1.2
Distance (km): 8.2781536
Magnitude: 7.8644919
Epsilon (mean values): 1.405447
Azimuth: 36.358309
Latitude: 33.853076
Longitude: -116.34417
UC33brAvg_FM31 (opt):

Percent Contributed: 2.61
Distance (km): 6.4949545
Magnitude: 5.8623336
Epsilon (mean values): 1.9321758
UC33brAvg_FM32 (opt):

Percent Contributed: 2.61
Distance (km): 6.4941944
Magnitude: 5.8617784
Epsilon (mean values): 1.9323608
PSHA Deaggregation. %contributions.
site: Test
longitude: 116.394°W
latitude: 33.796°E
imt: Peak Ground Acceleration
vs30 = 259 m/s (Site class D)
return period: 2475 yrs.
#This deaggregation corresponds to: Source Type: System Summary statistics for PSHA PGA deaggregation, r=distance, E=epsilon:

Deaggregation targets:

Return period: 2475 yrs
Exceedance rate: 0.0004040404 yr-1
PGA ground motion: 0.94442438 g
Recovered targets:

Return period: 3248.499 yrs
Exceedance rate: 0.0003.0783448 yr-1
Totals:

Binned: 77.01 %
Residual: 0 %
Trace: 0.04 %
Mean (over all sources):
m: 7.63
r: 7.75 km
Eo: 1.52 a
Mode (largest m -r bin):
m: 7.49
r: 6.65 km
co: 1.5 a
Contribution: 16.3 %
Mode (largest m -r -E0 bin):
m: 7.49
r: 6.61 km
co: 1.39 a
Contribution: 11.81 %
Discretization:
r: min = 0.0, max = 1000.0, A = 20.0 km
m: min = 4.4, max = 9.4, A = 0.2
E: min = -3.0, max = 3.0, A = 0.5 a
Epsilon keys:

E0: [—° .. —2.5)
El: [-2.5 .. —2.0)
E2: [-2.0 .. —1.5)
E3: [-1.5 .. —1.0)
E4: [-1.0 .. —0.5)
c5: [-0.5 .. 0.0)
E6: [0.0 .. 0.5)
E7: [0.5 .. 1.0)
E8: [1.0 .. 1.5)
475

E9: [1.5 .. 2.0)
E10: [2.0 .. 2.5)
E11: [2.5 .. +00]
Closest Distance, rRup (km)
Magnitude (Mw) ALL E
E=[-1.5,-1) E=[-1,-0.5) E=[-0.5,0) E=[0,0.5)
E=[2,2.5) E=[2.5,-)
70 8.1 0.000 0.000 0.000 0.000 0.000
70 8.3 0.000 0.000 0.000 0.000 0.000
50 7.5 0.000 0.000 0.000 0.000 0.000
50 7.7 0.000 0.000 0.000 0.000 0.000
50 7.9 0.015 0.000 0.000 0.000 0.000
50 8.1 0.005 0.000 0.000 0.000 0.000
50 8.3 0.005 0.000 0.000 0.000 0.000
30 6.5 0.000 0.000 0.000 0.000 0.000
30 6.7 0.001 0.000 0.000 0.000 0.000
30 6.9 0.005 0.000 0.000 0.000 0.000
30 7.1 0.042 0.000 0.000 0.000 0.000
30 7.3 0.050 0.000 0.000 0.000 0.000
30 7.5 0.108 0.000 0.000 0.000 0.000
30 7.7 0.142 0.000 0.000 0.000 0.000
30 7.9 0.418 0.000 0.000 0.000 0.000
30 8.1 0.749 0.000 0.000 0.000 0.000
30 8.3 0.466 0.000 0.000 0.000 0.000
10 6.1 0.016 0.000 0.000 0.000 0.000
10 6.3 0.834 0.000 0.000 0.000 0.000
10 6.5 2.382 0.000 0.000 0.000 0.000
10 6.7 0.501 0.000 0.000 0.000 0.000
10 6.9 1.160 0.000 0.000 0.000 0.000
10 7.1 1.266 0.000 0.000 0.000 0.000
10 7.3 14.930 0.000 0.000 0.000 0.000
10 7.5 16.300 0.000 0.000 0.000 0.000
10 7.7 13.054 0.000 0.000 0.000 0.000
10 7.9 7.178 0.000 0.000 0.000 0.000
10 8.1 13.116 0.000 0.000 0.000 0.000
10 8.3 4.263 0.000 0.000 0.000 0.000
Principal Sources (faults, subduction, random
UC33brAvg_FM31:

Percent Contributed: 38.53
Distance (km): 7.7522696
Magnitude: 7.6290489
Epsilon (mean values): 1.5183046
San Andreas (San Gorgonio Pass -Garnet Hill) [1] :

Percent Contributed: 3.95
Distance (km): 8.2781536
Magnitude: 7.8816596
Epsilon (mean values): 1.3120476
Azimuth: 36.358309
Latitude: 33.853076
Longitude: -116.34417
UC33brAvg_FM32:

Percent Contributed: 38.48
Distance (km): 7.7441979
Magnitude: 7.6245993
Epsilon (mean values): 1.5185216
San Andreas (San Gorgonio Pass -Garnet HI11) [1] :

Percent Contributed: 30.96
Distance (km): 6.5353046
Magnitude: 7.6018745
Epsilon (mean values): 1.478169
Azimuth: 31.71136
Latitude: 33.845511
Longitude: -116.35786
E=(--,-2.5) €=[-2.5,-2) E=[-2,-1.5)
E=[0.5,1) E=[1,1.5) E=[1.5,2)

0.000 0.000 0.000

0.000 0.000 0.000
o.000 o.000 o.000

0.000 0.000 0.000

0.000 0.000 0.000
seismicity having

0.000 0.000 0.000

0.000 0.000 0.003

0.000 0.000 0.002

0.000 0.000 0.000

0.000 0.000 0.519

0.000 0.004 1.387

0.000 0.004 0.438

0.000 0.008 0.970

0.000 0.231 0.506

0.000 9.507 3.762

0.000 11.806 3.651

0.000 9.798 2.632

0.000 5.286 1.522

0.012 9.984 2.531

0.495 2.796 0.795
> 3% contribution

0.000 0.000

0.000 0.015

0.000 0.005

0.001 0.005

0.000 0.000

0.000 0.001

0.000 0.005

0.000 0.042

0.001 0.049

0.011 0.097

0.017 0.125

0.166 0.252

0.493 0.253

0.375 0.089

0.000 0.016

0.277 0.038

0.497 0.495

0.042 0.017

0.159 0.023

0.455 0.075

1.637 0.024

0.842 0.000

0.624 0.000

0.368 0.002

0.589 0.001

0.177 0.000
476

San Andreas (North Branch Mill Creek) [10]:

Percent Contributed: 4.16
Distance (km): 8.2781536
Magnitude: 7.8512625
Epsilon (mean values): 1.3196983
Azimuth: 36.358309
Latitude: 33.853076
Longitude: -116.34417
PSHA Deaggregation. %contributions.
site: Test
longitude: 116.394°W
latitude: 33.796°E
imt: Peak Ground Acceleration
vs30 = 259 m/s (Site class D)
return period: 2475 yrs.
#This deaggregation corresponds to: Source Type: Grid
Summary statistics for PSHA PGA deaggregation, r=distance, E=epsilon:

Deaggregation targets:

Return period: 2475 yrs
Exceedance rate: 0.0004040404 yr-1
PGA ground motion: 0.94442438 g
Recovered targets:

Return period: 3248.499 yrs
Exceedance rate: 0.00030783448 yr-'
Totals:

Binned: 22.99 %
Residual: 0 %
Trace: 0.06 %
Mean (over all sources):
m: 5.81
r: 6.74 km
Eo: 1.8 O
Mode (largest m -r bin):
m: 5.5
r: 6.19 km

1.75 o
Ep:

Contribution: 3.55
Mode (largest m -r -E0
m: 5.3
r: 4.87 km
Eo: 1.76 o
Contribution: 2.4 %
Discretization:
r: min = 0.0, max = 1000.0, A = 20.0 km
m: min = 4.4, max = 9.4, A = 0.2
E: min = -3.0, max = 3.0, A = 0.5 a
Epsilon keys:

EO: [-°° .. -2.5)
E1: [-2.5 .. -2.0)
E2: [-2.0 .. -1.5)
E3: [-1.5 .. -1.0)
E4: [-1.0 .. -0.5)
E5: [-0.5 .. 0.0)
E6: [0.0 .. 0.5)
E7: [0.5 .. 1.0)
E8: [1.0 .. 1.5)
E9: [1.5 .. 2.0)
E10: [2.0 .. 2.5)
Ell: [2.5 .. +co]
Closest
Distance,
E=[-1.5,-1)
E=[2,2.5)
50 7.5 0.000
50 7.7 0.000
50 7.9 0.000
30 6.1 0.000
30 6.3 0.005
30 6.5 0.005
30 6.7 0.010
bin)
rRup (km) Magnitude (Mw) ALLE E=[-2.5,-2) E=[-2,-1.5)
E=[-1,-0.5) E=[-0.5,0) E=[0,0.5) E=[0.5,1) E=[1,1.5) E=[1.5,2) E=[2.5,x)

0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000

0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005

0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.002 0.008 477

30 6.9 0.011 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.002 0.009 30 7.1 0.010 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.003 0.006 30 7.3 0.007 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.003 0.004 30 7.5 0.003 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.002 0.001 30 7.7 0.001 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 30 7.9 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 10 5.1 2.816 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 1.104 1.403 0.309 10 5.3 3.142 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 2.397 0.289 0.456 10 5.5 3.553 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 1.763 1.059 0.256 0.474 10 5.7 3.036 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 1.399 0.866 0.398 0.372 10 5.9 2.387 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.993 0.677 0.475 0.242 10 6.1 2.712 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.662 1.011 0.877 0.162 10 6.3 2.013 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.429 1.025 0.466 0.092 10 6.5 1.429 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.034 0.399 0.675 0.253 0.068 10 6.7 0.832 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.065 0.233 0.367 0.134 0.033 10 6.9 0.539 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.057 0.128 0.234 0.105 0.017 10 7.1 0.303 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.042 0.080 0.112 0.064 0.005 10 7.3 0.136 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.022 0.042 0.042 0.029 0.002 10 7.5 0.037 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.006 0.012 0.013 0.006 0.000 10 7.7 0.004 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.001 0.001 0.001 0.001 0.000 10 7.9 0.001 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 Principal Sources (faults, subduction, random seismicity having > 3% contribution UC33brAvg_FM31 (opt):

Percent Contributed: 11.5
Distance (km): 6.7410744
Magnitude: 5.807404
Epsilon (mean values): 1.8045724
PointSourceFinite: -116.394, 33.801:

Percent Contributed: 3.82
Distance (km): 4.9165462
Magnitude: 5.6568818
Epsilon (mean values): 1.5987339
Azimuth: 0
Latitude: 33.800983
Longitude: -116.39434
PointSourceFinite: -116.394, 33.801:

Percent Contributed: 3.82
Distance (km): 4.9165462
Magnitude: 5.6568818
Epsilon (mean values): 1.5987339
Azimuth: 0
Latitude: 33.800983
Longitude: -116.39434
UC33brAvg_FM32 (opt):

Percent Contributed: 11.49
Distance (km): 6.740285
Magnitude: 5.806952
Epsilon (mean values): 1.8046318
PointSourceFinite: -116.394, 33.801:

Percent Contributed: 3.82
Distance (km): 4.9166413
Magnitude: 5.6565838
Epsilon (mean values): 1.5988436
Azimuth: 0
Latitude: 33.800983
Longitude: -116.39434
PointSourceFinite: -116.394, 33.801:

Percent Contributed: 3.82
Distance (km): 4.9166413
Magnitude: 5.6565838
Epsilon (mean values): 1.5988436
Azimuth: 0
Latitude: 33.800983
Longitude: -116.39434
478

APPENDIX D

DRY SAND SETTLEMENT
�PETRAS 479
GEOSCIENCE^
SOt ID AS A ROCK

Petra Geosciences, Inc.

I GEOLOGISIMIK Orange County Office
Vr WI DO 7Fi NUM106. VOLY O© TMf 160 3190 Airport Loop Drive, Suite J1, Costa Mesa, California 92626 www.petra-inc.com

SUMMARY CALCULATION REPORT
Project title : 24-112 National Core Apartments
Location : Rancho Mirage
Vertical Settlements
2-

1.8-

1.6-

1.5-

1.4-
-"E"' 1.2-
Settlements

0.9 -

0.8 -

0.7 -

0.6 -

0.5 -

0.4 -

0.3 -

0.2 -

0.1 -

1.39 1.95
B-1 I&B 2014 B-1 NCEER
Test Name
LiqSVs 2.3.2.11 - SPT & Vs Liquefaction Assessment Software Project File: Z:\24-112 Liq & Settle.lsys
480

Petra Geosciences, Inc.

Orange County Office
CEO.8#ISM:KI
Goatee lhrl4ca4 S.1 w,wre
3190 Airport Loop Drive, Suite 31, Costa Mesa, California 92626 ■ ■ rl • www.petra-inc.com

SPT BASED LIQUEFACTION ANALYSIS REPORT
Project title : 24-112 National Core Apartments
Location : Rancho Mirage
:: Input parameters and analysis properties ::

Analysis method:

Fines correction method:

Sampling method:

Borehole diameter:

Rod length:

Hammer energy ratio:

Boulanger & Idriss, 2014
Boulanger & Idriss, 2014
Sampler wo liners
200mm

3.30 ft

1.20 G.W.T. (in -situ):

G.W.T. (earthq.):

Earthquake magnitude Mw:

Peak ground acceleration:

Eq. external load:
160.00 ft
160.00 ft

7.49 0.87 g

0.00 tsf
SPT Name: B-1 I&B 2014
Raw SPT Data CSR - CRR Plot
10-
15-
20-
25-
i� 30 -
a 35-
v
40-
45-
50-
55-
60-
65-
I
0 10 20 30 40 50
SPT Count (blows/ft)

0.8 _

0.7-

0.6-
5-
10-
15-
20-
25-
+_ 30-
L
35-
-
40-
45-
50-
55-
60-
65-
0 0.2 0.4 0.6 0.8 1

CSR - CRR
CRR 7.50 clean sand curve
10 15
20 25
w 30
L
Q 35
a)
o
40 45
50 55
60 65
Factor of Safety
10 15 20 25 30 35 40 45 50
Corrected Blow Count N1(60),cs
FS Plot
5-
10-
15-
20-
25-
30-
L
a 35-
I)
O
40-
45-
50-
55-
60-
65-
LPI
0 Liquefaction potential
F.S. color scheme
▪ Almost certain it will liquefy
▪ Very likely to liquefy
❑ Liquefaction and no liqk are equally likely
• Unlike to liquefy
▪ Almost certain it will not liquefy
LPI color scheme
▪ Very high risk
• High risk
❑ Low risk
LiqSVs 2.3.2.11 - SPT & Vs Liquefaction Assessment Software Project File: Z:\24-112 Liq & Settle.lsys
481
Page: 1

This software is registered to: Kenton Buzbee
:: Overall Liquefaction Assessment Analysis Plots ::

Raw SPT Data CSR - CRR Plot FS Plot Vertical Liq. Settlements Lateral Liq. Displacements 2-
4 4-
4 4-
4_
6-
6-
8-
6 8
F--
6-
8-
f f
6-
8-
8 10-

10-
12-
10 12
-
-
--
---
10-
12-
10-
12-
12-
-
14 -
14 F--
-
14-
t-- ---}
-
14-
14-
16-
16-
-
16 ----
16-
-
•- - -
-
16-
-
18-
18 -
--
18 18-
i---
18-
20-
-
_
20 _
22-
----
;
20 22
F--
-
- ---:-
_
20 _
22-
f
_
20-
22-
22-
24-
26-
24-
26-
--
---i -
24 26
;--
--
24-
26-
24-
26-
28-
28-
----=------
-- -I
28 -----j-
28-

28-
30-
30-
----f
;
30 F
30-
}
; -
30-
32-
32-
v 32
v 32-
v 32-
.5 34-
a
a) 36-
t 34-
a-
36-
---:
--
-c 34
a
36 .
:--
-
+
-C 34-
a
cu 36-
1 1
1 -C 34-
-45
-
a) 36-
O
38-
38-
---;
f
i
38 f--
----J-
38-
f---- -----
38-
40-

42-
42-
!
42 42-
42-
44-
46-�
44-
46-
;
44 46
F
44-
46-
44-
46-
48-
50-1.
ill
48-
50-

48 50
T
48-
-
50-
48-
50-
52-
52_
1 52
--'
S2-
52-
54-
56-
�
54-
{
54 F--
54-
-
54-
58-
56-
-
T- - -
56 -
--T
56-
-
56_
-
60-1
III
-
58-
60-
58 60
-
----r
58-
60-
58_
60-
62-
_
F
_
_
64 66-
-
64-
-
r
----,
62 64
-
----,-
62-
64-
+

6Z--
64-
-
-. .
i i i i i i i i i
,
0 10 20 30 40 50 0 0.2 0.4 0.6 0.8 1 0 0.5 1 1.5 2 0 0.5 1 0 SPT Count (blows/ft) CSR - CRR Factor of Safety Cuml. Settlement (in) Cuml. Displacement (ft) LiqSVs 2.3.2.11 - SPT & Vs Liquefaction Assessment Software Project File: Z:\24-112 Liq & Settle.lsys
482
Page: 2

This software is registered to: Kenton Buzbee
:: Field input data ::

Test SPT Field
Depth Value
(ft) (blows)
Fines
Content
(0/0)
Unit
Weight
(pcf)
Infl. Can
Thickness Liquefy
(ft)

2.50 5.00

7.50 10.00

15.00 20.00

25.00 30.00

35.00 40.00

45.00 50.00

55.00 60.00

65.00 14
14 8
15 35
43 34
37 47
33 23
43 41
16 62

0.00 0.00

0.00 115.00
115.00
110.00
110.00
110.00
110.00
110.00
110.00
110.00
110.00
110.00
110.00
110.00
110.00
110.00

3.75 3.00

2.00 3.75

5.00 5.00

5.00 Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Abbreviations
Depth:

SPT Field Value:

Fines Content:

Unit Weight:

Infl. Thickness:

Can Liquefy:

Depth at which test was performed (ft)
Number of blows per foot
Fines content at test depth (%)
Unit weight at test depth (pcf)
Thickness of the soil layer to be considered in settlements analysis (ft) User defined switch for excluding/including test depth from the analysis procedure :: Cyclic Resistance Ratio (CRR) calculation data ::

Depth SPT Unit cry up a'„, m CN CE CB CR Cs (N1)60 FC A(N1)6o (Nikocs CRR7.5 (ft) Field Weight (tsf) (tsf) (tsf) (%)
Value (pcf)

2.50 14 115.00 0.14 0.00 0.14 0.37 1.70 1.20 1.15 0.75 1.30 32 0.00 0.00 32 4.000

5.00 14 115.00 0.29 0.00 0.29 0.36 1.60 1.20 1.15 0.75 1.30 30 0.00 0.00 30 4.000

7.50 8 110.00 0.42 0.00 0.42 0.46 1.53 1.20 1.15 0.80 1.18 16 0.00 0.00 16 4.000

10.00 15 110.00 0.56 0.00 0.56 0.39 1.28 1.20 1.15 0.85 1.26 28 0.00 0.00 28 4.000

15.00 35 110.00 0.84 0.00 0.84 0.26 1.06 1.20 1.15 0.85 1.30 57 0.00 0.00 57 4.000

20.00 43 110.00 1.11 0.00 1.11 0.26 0.99 1.20 1.15 0.95 1.30 72 0.00 0.00 72 4.000

25.00 34 110.00 1.39 0.00 1.39 0.26 0.93 1.20 1.15 0.95 1.30 54 0.00 0.00 54 4.000

30.00 37 110.00 1.66 0.00 1.66 0.26 0.89 1.20 1.15 1.00 1.30 59 0.00 0.00 59 4.000

35.00 47 110.00 1.94 0.00 1.94 0.26 0.85 1.20 1.15 1.00 1.30 72 0.00 0.00 72 4.000

40.00 33 110.00 2.21 0.00 2.21 0.26 0.82 1.20 1.15 1.00 1.30 49 0.00 0.00 49 4.000

45.00 23 110.00 2.49 0.00 2.49 0.36 0.73 1.20 1.15 1.00 1.30 30 0.00 0.00 30 4.000

50.00 43 110.00 2.76 0.00 2.76 0.26 0.78 1.20 1.15 1.00 1.30 60 0.00 0.00 60 4.000

55.00 41 110.00 3.04 0.00 3.04 0.26 0.76 1.20 1.15 1.00 1.30 56 0.00 0.00 56 4.000

60.00 16 110.00 3.31 0.00 3.31 0.47 0.59 1.20 1.15 1.00 1.17 15 0.00 0.00 15 4.000

65.00 62 110.00 3.59 0.00 3.59 0.26 0.73 1.20 1.15 1.00 1.30 81 0.00 0.00 81 4.000 LiqSVs 2.3.2.11 - SPT & Vs Liquefaction Assessment Software Project File: Z:\24-112 Liq & Settle.lsys
483
Page: 3

This software is registered to: Kenton Buzbee
:: Cyclic Resistance Ratio (CRR) calculation data ::

Depth SPT Unit a, uo dvo m
(ft) Field Weight (tsf) (tsf) (tsf)
Value (pcf)
Cry CE CB CR
Cs (N1)60 FC A(N1)6o (N1)6oas CRR7.5
(0/0)
Abbreviations
av:
uo:
a'vo :
m:

CN:

CE:

CB:

CR:

CB:

N1(60):

O(N1)6o
N1(60)CS:

CRR7.5:

Total stress during SPT test (tsf)
Water pore pressure during SPT test (tsf)
Effective overburden pressure during SPT test (tsf)
Stress exponent normalization factor
Overburden corretion factor
Energy correction factor
Borehole diameter correction factor
Rod length correction factor
Liner correction factor
Corrected N5- to a 60% energy ratio
Equivalent clean sand adjustment
Corected Ni(60) value for fines content
Cyclic resistance ratio for M=7.5
:: Cyclic Stress Ratio calculation (CSR fully adjusted and normalized) ::

Depth Unit
(ft) Weight
(pcf)
a,eq uo,eq dvo,eq
(tsf) (tsf) (tsf)
rd a CSR MSF. (N1)60. MSF CSReq,M=7.5 Ksigma CSR* FS

2.50 115.00 0.14 0.00 0.14 1.00 1.00 0.566 2.12 32 1.00 0.564 1.10 0.513 2.000 •

5.00 115.00 0.29 0.00 0.29 0.99 1.00 0.563 2.00 30 1.00 0.561 1.10 0.510 2.000 •

7.50 110.00 0.42 0.00 0.42 0.99 1.00 0.559 1.35 16 1.00 0.558 1.10 0.508 2.000 •

10.00 110.00 0.56 0.00 0.56 0.98 1.00 0.555 1.88 28 1.00 0.553 1.10 0.503 2.000 •

15.00 110.00 0.84 0.00 0.84 0.97 1.00 0.546 2.20 57 1.00 0.544 1.07 0.509 2.000 •

20.00 110.00 1.11 0.00 1.11 0.95 1.00 0.536 2.20 72 1.00 0.534 0.99 0.542 2.000 •

25.00 110.00 1.39 0.00 1.39 0.93 1.00 0.525 2.20 54 1.00 0.523 0.92 0.568 2.000 0

30.00 110.00 1.66 0.00 1.66 0.91 1.00 0.513 2.20 59 1.00 0.511 0.87 0.590 2.000

35.00 110.00 1.94 0.00 1.94 0.89 1.00 0.501 2.20 72 1.00 0.499 0.82 0.607 2.000 0

40.00 110.00 2.21 0.00 2.21 0.86 1.00 0.488 2.20 49 1.00 0.486 0.78 0.622 2.000 •

45.00 110.00 2.49 0.00 2.49 0.84 1.00 0.475 2.00 30 1.00 0.474 0.83 0.573 2.000

50.00 110.00 2.76 0.00 2.76 0.82 1.00 0.462 2.20 60 1.00 0.461 0.72 0.643 2.000 •

55.00 110.00 3.04 0.00 3.04 0.80 1.00 0.450 2.20 56 1.00 0.448 0.69 0.650 2.000 •

60.00 110.00 3.31 0.00 3.31 0.77 1.00 0.437 1.32 15 1.00 0.437 0.87 0.500 2.000 0

65.00 110.00 3.59 0.00 3.59 0.75 1.00 0.425 2.20 81 1.00 0.423 0.64 0.662 2.000 • Abbreviations
av,eg:
lb,eq:
dvo,eq:
rd:
a:

CSR :

MSF :

CSReq,M=7.5•
Ksigma
CSR*:

FS:
*** User FS:

Total overburden pressure at test point, during earthquake (tsf) Water pressure at test point, during earthquake (tsf)
Effective overburden pressure, during earthquake (tsf)
Nonlinear shear mass factor
Improvement factor due to stone columns
Cyclic Stress Ratio
Magnitude Scaling Factor
CSR adjusted for M=7.5
Effective overburden stress factor
CSR fully adjusted (user FS applied)***
Calculated factor of safety against soil liquefaction

1.00 :: Liquefaction potential according to Iwasaki ::

Depth FS F wz Thickness
(ft) (ft)
IL

2.50 2.000 0.00 9.62 2.50 0.00

5.00 2.000 0.00 9.24 2.50 0.00
LiqSVs 2.3.2.11 - SPT & Vs Liquefaction Assessment Software Project File: Z:\24-112 Liq & Settle.lsys
484
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This software is registered to: Kenton Buzbee
:: Liquefaction potential according to Iwasaki ::

Depth FS F wz Thickness IL
(ft) (ft)

7.50 2.000 0.00 8.86 2.50 0.00

10.00 2.000 0.00 8.48 2.50 0.00

15.00 2.000 0.00 7.71 5.00 0.00

20.00 2.000 0.00 6.95 5.00 0.00

25.00 2.000 0.00 6.19 5.00 0.00

30.00 2.000 0.00 5.43 5.00 0.00

35.00 2.000 0.00 4.67 5.00 0.00

40.00 2.000 0.00 3.90 5.00 0.00

45.00 2.000 0.00 3.14 5.00 0.00

50.00 2.000 0.00 2.38 5.00 0.00

55.00 2.000 0.00 1.62 5.00 0.00

60.00 2.000 0.00 0.86 5.00 0.00

65.00 2.000 0.00 0.09 5.00 0.00
Overall potential IL : 0.00
IL = 0.00 - No liquefaction
IL between 0.00 and 5 - Liquefaction not probable
IL between 5 and 15 - Liquefaction probable
IL > 15 - Liquefaction certain
:: Vertical settlements estimation for dry sands ::

Depth (N1)60 Tait
(ft)
P Gmax a
(tsf)
b
Y
E15
Nc ENc ENc Ah AS
weight (%) (ft) (in)
factor

2.50 32 0.08 0.10 440.42

5.00 30 0.16 0.19 609.59

7.50 16 0.24 0.28 601.05

10.00 28 0.31 0.38 833.28

15.00 57 0.46 0.56 1Ltfti.b

20.00 72 0.60 0.75 105.4

25.00 54 0.73 0.93 1bZy.0

30.00 59 0.85 1.11 1,3RR'S

35.00 72 0.97 1.30 21Ri./

40.00 49 1.08 1.48 191.5

45.00 30 1.18 1.67 1 / i.0

50.00 60 1.28 1.85 LiSU./

55.00 56 1.37 2.04 L4iy.b

60.00 15 1.45 2.22 164L. j

65.00 81 1.52 2.40 Ly�Jtf.4
9 0.13

0.13 0.14

0.14 0.15

0.15 0.16

0.17 0.17

0.18 0.19

0.20 0.20

0.21 0.22
26059.76
17193.03
13598.84
11493.75
9051.99
7634.05
6686.45
5998.99
5472.55
5053.65
4710.61
4423.37
4178.55
3966.81
3781.46

0.00 0.00

0.01 0.00

0.00 0.00

0.00 0.01

0.00 0.00

0.00 0.01

0.00 0.00

0.01 0.00

15.06 15.06

15.06 0.95

0.90 0.85

0.80 0.70

0.60 0.50

0.40 0.30

0.20 0.10

0.00 0.00

0.16 0.20

1.38 0.25

0.04 0.03

0.05 0.04

0.03 0.06

0.18 0.04

0.04 0.82

0.02 3.75

3.00 2.00

3.75 5.00

5.00 5.00

0.070

0.071

0.330

0.112

0.024

0.015

0.029

0.024

0.016

0.036

0.107

0.022

0.025

0.491

0.012
Cumulative settlemetns: 1.385
Abbreviations
Tav: Average cyclic shear stress
p: Average stress
Gmax: Maximum shear modulus (tsf)
a, b: Shear strain formula variables
y: Average shear strain
£15: Volumetric strain after 15 cycles
Nc: Number of cycles
£Nc: Volumetric strain for number of cycles N, (%)
ah: Thickness of soil layer (in)
AS: Settlement of soil layer (in)
LiqSVs 2.3.2.11 - SPT & Vs Liquefaction Assessment Software Project File: Z:\24-112 Liq & Settle.lsys
485
Page: 5

Petra Geosciences, Inc.

Orange County Office
CEO.8#ISM:KI
Goatee lhrl4ca4 S.1 w,wre
3190 Airport Loop Drive, Suite 31, Costa Mesa, California 92626 ■ ■ rl • www.petra-inc.com

SPT BASED LIQUEFACTION ANALYSIS REPORT
Project title : 24-112 National Core Apartments
Location : Rancho Mirage
:: Input parameters and analysis properties ::

Analysis method:

Fines correction method:

Sampling method:

Borehole diameter:

Rod length:

Hammer energy ratio:

NCEER 1998
NCEER 1998
Sampler wo liners
200mm

3.30 ft

1.20 G.W.T. (in -situ):

G.W.T. (earthq.):

Earthquake magnitude Mw:

Peak ground acceleration:

Eq. external load:
160.00 ft
160.00 ft

7.49 0.87 g

0.00 tsf
SPT Name: B-1 NCEER
Raw SPT Data CSR - CRR Plot
10-
15-
20-
25-
i� 30
a 35-
v
40-
45-
50-
55-
60-
65-
I
0 10 20 30 40 50
SPT Count (blows/ft)

0.8 0.7 -
G) 0.4 —

0.2 -

0.1-

0.0 _
0 5
5-
10-
15-
20-
25-
+_ 30-
L
35—
a.)
-
40 -
45-
50-
55-
60-
65-
0 0.2 0.4 0.6 0.8 1

CSR - CRR
CRR 7.50 clean sand curve
10 15
20 25
w 30
L
Q 35
a)
o
40 45
50 55
60 65
FS Plot
Factor of Safety
10 15 20 25 30 35 40 45 50
Corrected Blow Count N1(60),cs
5-
10-
15-
20-
25-
30-
L
a 35-
I)
O
40-
45-
50-
55-
60-
65-
LPI
0 Liquefaction potential
F.S. color scheme
▪ Almost certain it will liquefy
▪ Very likely to liquefy
❑ Liquefaction and no liqk are equally likely
• Unlike to liquefy
▪ Almost certain it will not liquefy
LPI color scheme
▪ Very high risk
• High risk
❑ Low risk
LiqSVs 2.3.2.11 - SPT & Vs Liquefaction Assessment Software Project File: Z:\24-112 Liq & Settle.lsys
486
Page: 6

This software is registered to: Kenton Buzbee
:: Overall Liquefaction Assessment Analysis Plots ::

Raw SPT Data CSR - CRR Plot FS Plot Vertical Liq. Settlements Lateral Liq. Displacements 2 4-
4-
_
:. .. _
4 J
4-
4-
6-
6-
8-
------ ---i-----
-

6 8-
1 --i
6-
8-
6-
8-
8 10-
10-
12-
-
10 12
10-
12-
-
10-
12-
12-
14 14
14-
14-
14-
16-
I
--
16 16-
16-
16-
-
--
----'-
-
-
18-
18-
-I--
18-
-
I
18-
1 ;-
18-
-
20-
20 .--
-
20-
20-
20-
22-
;
22 --
---'
-
-
22-
--
22-
22-
24-
26-
24-
26-
24 26-
-
-
'
24-
26-
_i-
24-
26-
28-
28-
q____
28 f
28-
r
28-
30-
w
-.
30-
w
30 T
30-
S
30-
..
32-
32-
V 32
_
V 32-
_
-S -;
v32 -
34-
-
0 36-
34-
0 36-
1 --- -,------'-
--'-
34 0 36-
I
-
'
'-
34-
0 36-
t i
4 34 _
0 36-
38-
38-
;
;---
38 38-
38-
4 0-
40-
-
------ -
40 F
40-
+ -
1 ----- 4--- --4---------F---
4 0-
42-
42-
;
42 L
42-
--r-- --; i-
4 2-
44-
46-_
44-
46-
---
44-
46 -
-
44-
46-
44-
46-
48 _

50-
48-
-
5O- --------4
}
---------
----',---
; .-.
4 8
50-
�
48:
-
50-
1 1

48-
52-
_
52-
I
__-: .r__
1 i --_.
_
52-
I
--
____T
_
52-
, I
;
_
52-
54-
56-
-
54-
-
54-
;--
----
-
54-
-
--
-
54_
..
58-
56-
56 56-
iL
56-
60 _-
58 - -
60-
---F ------ ;---
58 60
S8 _4
60-
F
58 60-
62-
_
_
l
64-
66-
62-
64-
---; ;---
--L --
62-
64-
;--
;--
-
---- -
62-
64-
r
L
62-
64_
_
1 i , i 1 i , i 1
1 i , i 1 i , i 1
I I 1 I I I 1 i
0 10 20 30 40 50 0 0.2 0.4 0.6 0.8 1 0 0.5 1 1.5 2 0 0.5 1 1.5 0 SPT Count (blows/ft) CSR - CRR Factor of Safety Cuml. Settlement (in) Cuml. Displacement (ft) LiqSVs 2.3.2.11 - SPT & Vs Liquefaction Assessment Software Project File: Z:\24-112 Liq & Settle.lsys
487
Page: 7

This software is registered to: Kenton Buzbee
:: Field input data ::

Test SPT Field
Depth Value
(ft) (blows)
Fines
Content
(0/0)
Unit
Weight
(pcf)
Infl. Can
Thickness Liquefy
(ft)

2.50 5.00

7.50 10.00

15.00 20.00

25.00 30.00

35.00 40.00

45.00 50.00

55.00 60.00

65.00 14
14 8
15 35
43 34
37 47
33 23
43 41
16 62

0.00 0.00

0.00 120.00
120.00
120.00
120.00
120.00
120.00
120.00
120.00
120.00
120.00
120.00
120.00
120.00
120.00
120.00

3.75 3.00

2.00 3.75

5.00 5.00

5.00 Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Abbreviations
Depth:

SPT Field Value:

Fines Content:

Unit Weight:

Infl. Thickness:

Can Liquefy:

Depth SPT Unit a up
(ft) Field Weight (tsf) (tsf)
Value (pcf)

2.50 14 120.00 0.15 0.00

5.00 14 120.00 0.30 0.00

7.50 8 120.00 0.45 0.00

10.00 15 120.00 0.60 0.00

15.00 35 120.00 0.90 0.00

20.00 43 120.00 1.20 0.00

25.00 34 120.00 1.50 0.00

30.00 37 120.00 1.80 0.00

35.00 47 120.00 2.10 0.00

40.00 33 120.00 2.40 0.00

45.00 23 120.00 2.70 0.00

50.00 43 120.00 3.00 0.00

55.00 41 120.00 3.30 0.00

60.00 16 120.00 3.60 0.00

65.00 62 120.00 3.90 0.00
aevo CN
(tsf)

0.15 1.64

0.30 1.48

0.45 1.35

0.60 1.25

0.90 1.07

1.20 0.94

1.50 0.84

1.80 0.76

2.10 0.69

2.40 0.63

2.70 0.59

3.00 0.55

3.30 0.51

3.60 0.48

3.90 0.45
CE
CB
CR Cs (N1)60 Fines a (3 (Ni)6o. CRR7.5
Content
(0/0)

1.20 1.15 0.75 1.20 29 0.00 0.00 1.00 29 4.000

1.20 1.15 0.75 1.20 26 0.00 0.00 1.00 26 4.000

1.20 1.15 0.75 1.20 13 0.00 0.00 1.00 13 4.000

1.20 1.15 0.85 1.20 26 0.00 0.00 1.00 26 4.000

1.20 1.15 0.85 1.20 53 0.00 0.00 1.00 53 4.000

1.20 1.15 0.95 1.20 64 0.00 0.00 1.00 64 4.000

1.20 1.15 0.95 1.20 45 0.00 0.00 1.00 45 4.000

1.20 1.15 1.00 1.20 46 0.00 0.00 1.00 46 4.000

1.20 1.15 1.00 1.20 54 0.00 0.00 1.00 54 4.000

1.20 1.15 1.00 1.20 35 0.00 0.00 1.00 35 4.000

1.20 1.15 1.00 1.20 22 0.00 0.00 1.00 22 4.000

1.20 1.15 1.00 1.20 39 0.00 0.00 1.00 39 4.000

1.20 1.15 1.00 1.20 35 0.00 0.00 1.00 35 4.000

1.20 1.15 1.00 1.20 13 0.00 0.00 1.00 13 4.000

1.20 1.15 1.00 1.20 46 0.00 0.00 1.00 46 4.000
LiqSVs 2.3.2.11 - SPT & Vs Liquefaction Assessment Software Project File: Z:\24-112 Liq & Settle.lsys
488
Page: 8

This software is registered to: Kenton Buzbee
:: Cyclic Resistance Ratio (CRR) calculation data ::

Depth SPT Unit as, uo a' o CN
(ft) Field Weight (tsf) (tsf) (tsf)
Value (pcf)
CE
CB CR Cs (N1)60 Fines a (3 (N1)6ocs CRR7.5
Content
(%)
Abbreviations
Cry:
uo:
dvo:

CN:

C1:

CB:

CR:

Cs:

NI(6o):
a, 3:

NI(6o)os:

CRR7.5:

Total stress during SPT test (tsf)
Water pore pressure during SPT test (tsf)
Effective overburden pressure during SPT test (tsf)
Overburden corretion factor
Energy correction factor
Borehole diameter correction factor
Rod length correction factor
Liner correction factor
Corrected NSBr to a 60% energy ratio
Clean sand equivalent clean sand formula coefficients
Corected N1(6o) value for fines content
Cyclic resistance ratio for M=7.5
:: Cyclic Stress Ratio calculation (CSR fully adjusted and normalized) ::

Depth Unit av,eq uo,eq a'vo,eq rd a CSR MSF CSReq,M=7.s Ksigma CSR* FS (ft) Weight (tsf) (tsf) (tsf)
(pcf)

2.50 120.00 0.15 0.00 0.15 1.00 1.00 0.563 1.00 0.562 1.00 0.562 2.000 •

5.00 120.00 0.30 0.00 0.30 0.99 1.00 0.560 1.00 0.558 1.00 0.558 2.000 0

7.50 120.00 0.45 0.00 0.45 0.98 1.00 0.557 1.00 0.555 1.00 0.555 2.000

10.00 120.00 0.60 0.00 0.60 0.98 1.00 0.554 1.00 0.552 1.00 0.552 2.000 0

15.00 120.00 0.90 0.00 0.90 0.97 1.00 0.548 1.00 0.546 1.00 0.546 2.000 •

20.00 120.00 1.20 0.00 1.20 0.96 1.00 0.541 1.00 0.539 0.98 0.553 2.000

25.00 120.00 1.50 0.00 1.50 0.94 1.00 0.533 1.00 0.531 0.93 0.569 2.000

30.00 120.00 1.80 0.00 1.80 0.92 1.00 0.521 1.00 0.519 0.90 0.577 2.000 0

35.00 120.00 2.10 0.00 2.10 0.89 1.00 0.504 1.00 0.502 0.87 0.576 2.000

40.00 120.00 2.40 0.00 2.40 0.85 1.00 0.481 1.00 0.480 0.85 0.565 2.000 0

45.00 120.00 2.70 0.00 2.70 0.80 1.00 0.454 1.00 0.453 0.83 0.546 2.000 •

50.00 120.00 3.00 0.00 3.00 0.75 1.00 0.426 1.00 0.424 0.81 0.523 2.000 •

55.00 120.00 3.30 0.00 3.30 0.70 1.00 0.398 1.00 0.397 0.80 0.498 2.000 •

60.00 120.00 3.60 0.00 3.60 0.66 1.00 0.373 1.00 0.372 0.78 0.475 2.000 0

65.00 120.00 3.90 0.00 3.90 0.62 1.00 0.352 1.00 0.351 0.77 0.455 2.000 Abbreviations
Qv,eq:

Lb,eq:
a'vo,eq:

Co] :
a:

CSR :

MSF :

CSReq,M=7.5:

Ksigma:

CSR*:

FS:
"` User FS:

Total overburden pressure at test point, during earthquake (tsf) Water pressure at test point, during earthquake (tsf)
Effective overburden pressure, during earthquake (tsf)
Nonlinear shear mass factor
Improvement factor due to stone columns
Cyclic Stress Ratio (adjusted for improvement)
Magnitude Scaling Factor
CSR adjusted for M=7.5
Effective overburden stress factor
CSR fully adjusted (user FS applied)**"
Calculated factor of safety against soil liquefaction

1.00 :: Liquefaction potential according to Iwasaki ::

Depth FS F wz Thickness IL
(ft) (ft)

2.50 5.00

7.50 2.000

2.000

0.00 0.00

0.00 9.62

9.24 8.86

2.50 2.50

2.50 0.00

0.00 0.00
LiqSVs 2.3.2.11 - SPT & Vs Liquefaction Assessment Software Project File: Z:\24-112 Liq & Settle.lsys
489
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This software is registered to: Kenton Buzbee
:: Liquefaction potential according to Iwasaki ::

Depth FS F wz Thickness IL
(ft) (ft)

10.00 15.00

20.00 25.00

30.00 35.00

40.00 45.00

50.00 55.00

60.00 65.00

2.000

0.00 0.00

8.48 7.71

6.95 6.19

5.43 4.67

3.90 3.14

2.38 1.62

0.86 0.09

2.50 5.00

5.00 5.00

0.00 0.00

0.00 0.00
Overall potential IL : 0.00
IL = 0.00 - No liquefaction
IL between 0.00 and 5 - Liquefaction not probable
IL between 5 and 15 - Liquefaction probable
IL > 15 - Liquefaction certain
:: Vertical settlements estimation for dry sands ::

Depth (N1)60 Tav
(ft)
p Gmax a
(tsf)
b Y £ls Plc £Nc Ah AS
(0/0) (°/O) (ft) (in)

2.50 29 0.08 0.10 435.37 0.13 25402.73 0.32 0.00 15.06 0.21 3.75 0.093

5.00 26 0.17 0.20 593.69 0.13 16759.55 0.40 0.00 15.06 0.29 3.00 0.106

7.50 13 0.25 0.30 577.12 0.14 13140.37 1.60 0.03 15.06 2.68 2.00 0.644

10.00 26 0.33 0.40 839.61 0.14 11057.18 0.42 0.00 15.06 0.31 3.75 0.138

15.00 53 0.49 0.60 1303.84 0.15 8669.41 0.16 0.00 15.06 0.05 5.00 0.030

20.00 64 0.65 0.80 1603.23 0.16 7295.02 0.14 0.00 15.06 0.03 5.00 0.021

25.00 45 0.80 1.00 1593.90 0.16 6380.88 0.22 0.00 15.06 0.08 5.00 0.049

30.00 46 0.94 1.21 1758.87 0.17 5719.68 0.21 0.00 15.06 0.08 5.00 0.046

35.00 54 1.06 1.41 2004.10 0.18 5214.39 0.17 0.00 15.06 0.05 5.00 0.031

40.00 35 1.16 1.61 1854.13 0.19 4812.92 0.25 0.00 15.06 0.13 5.00 0.076

45.00 22 1.23 1.81 1684.62 0.19 4484.53 0.37 0.00 15.06 0.33 5.00 0.199

50.00 39 1.28 2.01 2149.12 0.20 4209.81 0.17 0.00 15.06 0.08 5.00 0.046

55.00 35 1.31 2.21 2174.16 0.21 3975.82 0.17 0.00 15.06 0.08 5.00 0.051

60.00 13 1.34 2.41 1632.34 0.22 3773.58 0.39 0.01 15.06 0.66 5.00 0.398

65.00 46 1.37 2.61 2588.99 0.23 3596.63 0.11 0.00 15.06 0.04 5.00 0.024 Cumulative settlemetns: 1.953
Abbreviations
r„: Average cyclic shear stress
p: Average stress
Gmax: Maximum shear modulus (tsf)
a, b: Shear strain formula variables
y: Average shear strain (%)
£15: Volumetric strain after 15 cycles
Nc: Number of cycles
£Nc: Volumetric strain for number of cycles Nc (%)
Ah: Thickness of soil layer (in)
AS: Settlement of soil layer (in)
LiqSVs 2.3.2.11 - SPT & Vs Liquefaction Assessment Software Project File: Z:\24-112 Liq & Settle.lsys
490
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This software is registered to: Kenton Buzbee
:: Lateral displacements estimation for saturated sands ::

Depth (N1)60 Dr Ymax dz LDI LD
(ft) (%) (%) (ft) (ft)

2.50 29 75.39 0.00 3.75 0.000 0.00

5.00 26 71.39 0.00 3.00 0.000 0.00

7.50 13 50.48 0.00 2.00 0.000 0.00

10.00 26 71.39 0.00 3.75 0.000 0.00

15.00 53 100.00 0.00 5.00 0.000 0.00

20.00 64 100.00 0.00 5.00 0.000 0.00

25.00 45 100.00 0.00 5.00 0.000 0.00

30.00 46 100.00 0.00 5.00 0.000 0.00

35.00 54 100.00 0.00 5.00 0.000 0.00

40.00 35 82.83 0.00 5.00 0.000 0.00

45.00 22 65.67 0.00 5.00 0.000 0.00

50.00 39 87.43 0.00 5.00 0.000 0.00

55.00 35 82.83 0.00 5.00 0.000 0.00

60.00 13 50.48 0.00 5.00 0.000 0.00

65.00 46 100.00 0.00 5.00 0.000 0.00
Cumulative lateral displacements: 0.00
Abbreviations
Dr: Relative density (%)
Ymax: Maximum amplitude of cyclic shear strain (%)
dz: Soil layer thickness (ft)
LDI: Lateral displacement index (ft)
LD: Actual estimated displacement (ft)
LiqSVs 2.3.2.11 - SPT & Vs Liquefaction Assessment Software Project File: Z:\24-112 Liq & Settle.lsys
491
Page: 11

References
• Ronald D. Andrus, Hossein Hayati, Nisha P. Mohanan, 2009. Correcting Liquefaction Resistance for Aged Sands Using Measured to Estimated Velocity Ratio, Journal of Geotechnical and Geoenvironmental Engineering, Vol. 135, No. 6, June 1 • Boulanger, R.W. and Idriss, I. M., 2014. CPT AND SPT BASED LIQUEFACTION TRIGGERING PROCEDURES. DEPARTMENT OF

CIVIL & ENVIRONMENTAL ENGINEERING COLLEGE OF ENGINEERING UNIVERSITY OF CALIFORNIA AT DAVIS • Dipl.-Ing. Heinz J. Priebe, Vibro Replacement to Prevent Earthquake Induced Liquefaction, Proceedings of the Geotechnique- Colloquium at Darmstadt, Germany, on March 19th, 1998 (also published in Ground Engineering, September 1998), Technical paper 12-57E
• Robertson, P.K. and Cabal, K.L., 2007, Guide to Cone Penetration Testing for Geotechnical Engineering. Available at no cost at http://www.geologismiki.gr/
• Youd, T.L., Idriss, I.M., Andrus, R.D., Arango, I., Castro, G., Christian, J.T., Dobry, R., Finn, W.D.L., Harder, L.F., Hynes, M.E., Ishihara, K., Koester, J., Liao, S., Marcuson III, W.F., Martin, G.R., Mitchell, J.K., Moriwaki, Y., Power, M.S., Robertson, P.K., Seed, R., and Stokoe, K.H., Liquefaction Resistance of Soils: Summary Report from the 1996 NCEER and 1998 NCEER/NSF Workshop on Evaluation of Liquefaction Resistance of Soils, ASCE, Journal of Geotechnical & Geoenvironmental Engineering, Vol. 127, October, pp 817-833
• Zhang, G., Robertson. P.K., Brachman, R., 2002, Estimating Liquefaction Induced Ground Settlements from the CPT, Canadian Geotechnical Journal, 39: pp 1168-1180
• Zhang, G., Robertson. P.K., Brachman, R., 2004, Estimating Liquefaction Induced Lateral Displacements using the SPT and CPT, ASCE, Journal of Geotechnical & Geoenvironmental Engineering, Vol. 130, No. 8, 861-871 • Pradel, D., 1998, Procedure to Evaluate Earthquake -Induced Settlements in Dry Sandy Soils, ASCE, Journal of Geotechnical & Geoenvironmental Engineering, Vol. 124, No. 4, 364-368
• R. Kayen, R. E. S. Moss, E. M. Thompson, R. B. Seed, K. O. Cetin, A. Der Kiureghian, Y. Tanaka, K. Tokimatsu, 2013. Shear - Wave Velocity —Based Probabilistic and Deterministic Assessment of Seismic Soil Liquefaction Potential, Journal of Geotechnical and Geoenvironmental Engineering, Vol. 139, No. 3, March 1 LiqSVs 2.3.2.11 - SPT & Vs Liquefaction Assessment Software

APPENDIX E

PER COLA TION /INFILTRATION
PETRAS 493
GEOSCIENCE^
Sot ID AS A ROCK

Boring/Test Number: P-1
Total Depth of Boring, D 1 (ft):
10 Test Date:
6/7/2024
D
d
existing
Found
surface
f
Diameter of Hole, D (in):
8 Tested By:

KTM
Diameter of Casing, d (in):
2 USCS Soil Type:

SP
�:
' r
;r
�+
C"
�1
�;+
;+
Depth of Slotted Casing (ft):
5 to 10
Depth to Groundwater (ft):
?
Porosity of Annulus Material, n :

0.42 Ground Elevation (msl ft):
312
Depth from Existing Ground Surface to
Bottom of Prop.

Inflitration System (ft):
?
SANDY

SOIL CRITERIA
TEST
Trial
Time
Interval
Depth to Water,
D w
Change in
Water Level
Change in Height of Water
Greater Than Equal
No.

At (min.)
Initial, Do (ft.)
Final, Df (ft.)
AD (in.)
or to
6"? (Yes/No)*
:; *1
*'
1 r
+"
04 *'
r*r
��
;::
: r
'*•y
�;
` r
*r
*'
r+r
•r
•:
+r
�r
:
+r
: ::
r•r
r
it
.
it
rr
�r
'•'
r
;•
•
%
r• DI
P.1
•
r',
,•

r
r•
•'•'
r0!
:i
;*,
•
r�r
!i+
ear
a`r
r
rr
..
it
rr
:r
1 25

9.1 10

10.8 yes
2 25

9.10 10

10.8 yes
Standard Time Interval
Between Readings (min.), [* if yes = 10, if no = 30]: 30

PERCOLATION TEST
Trial
Time
Depth to Water, Dw
Change in
Percolation Rate
No.

Interval
at min.)
(
Initial, Do (ft.)
Final, Df (ft.)
Water Level
(•
All in.)
(min/in.)
(gal/day/ft^2)
::
1 10

8.60 10.00

16.80 0.60
132.32
2 10

8.60 10.00

16.80 0.60
132.32
3 10

8.55 10.00

17.40 0.57
133.20
4 10

8.60 10.00

16.80 0.60
132.32
5 10

8.55 10.00

17.40 0.57
133.20
6 10

8.55 10.00

17.40 0.57
133.20
TEST RESULTS**
**Raw Results. Does Not
Include a Factor of Safety
Inflitration Rate [Porchet Method]#
Percolation Rate
(inches/hour)
(min/in.)
(gal/day/ft^2)

12.00 0.57
133.20

FACTOR OF SAFETY
Testing Option
Testing Requirements
Factor of Safety
per Reference
Option 2
4 tests minimum with at least two borings per basin
3 " Where Infiltration Rate, It = Ali (60r) /At(r + av
( ) 2H g)
r= D / 2
Ho = DT - Do
Hf=DT-Df
AH=AD=Ho-Hf
Reference: Have = (H0+ Hf) / 2
RCFCWCD, Design Handbook for LID, dated September, 2011 PETRA GEOSCIENCES, INC.
3186 Airway Avenue, Suite
Costa Mesa, California 92626 PHONE: (714) 549-8921

COSTA MESA TEMECULA LOS ANGELES PALM DESERT CORONA ESCONDIDO

PERCOLATION TEST SUMMARY
Key Largo Avenue
Rancho Mira e, Riverside County, CA
* PETRA 'DATE:

June , 2024
I Appendix
'- OEO9CIENCE9-
J.N.: 24-112
E
494

APPENDIX F

STANDARD GRADING SPECIFICATIONS
PETRAS 495
GEOSCIENCE^
SOt ID AS A ROCK

STANDARD GRADING SPECIFICATIONS
These specifications present the usual and minimum requirements for projects on which Petra Geosciences, Inc. (Petra) is the geotechnical consultant. No deviation from these specifications will be allowed, except where specifically superseded in the preliminary geology and soils report, or in other written communication signed by the Soils Engineer and Engineering Geologist of record (Geotechnical Consultant).

I. GENERAL
A. The Geotechnical Consultant is the Owner's or Builder's representative on the project. For the purpose of these specifications, participation by the Geotechnical Consultant includes that observation performed by any person or persons employed by, and responsible to, the licensed Soils Engineer and Engineering Geologist signing the soils report.

B. The contractor should prepare and submit to the Owner and Geotechnical Consultant a work plan that indicates the sequence of earthwork grading, the number of "spreads" and the estimated quantities of daily earthwork to be performed prior to the commencement of grading.

This work plan should be reviewed by the Geotechnical Consultant to schedule personnel to perform the appropriate level of observation, mapping, and compaction testing as necessary.

C. All clearing, site preparation, or earthwork performed on the project shall be conducted by the Contractor in accordance with the recommendations presented in the geotechnical report and under the observation of the Geotechnical Consultant.

D. It is the Contractor's responsibility to prepare the ground surface to receive the fills to the satisfaction of the Geotechnical Consultant and to place, spread, mix, water, and compact the fill in accordance with the specifications of the Geotechnical Consultant. The Contractor shall also remove all material considered unsatisfactory by the Geotechnical Consultant.

E. It is the Contractor's responsibility to have suitable and sufficient compaction equipment on the job site to handle the amount of fill being placed. If necessary, excavation equipment will be shut down to permit completion of compaction to project specifications. Sufficient watering apparatus will also be provided by the Contractor, with due consideration for the fill material, rate of placement, and time of year.

F. After completion of grading a report will be submitted by the Geotechnical Consultant.

II. SITE PREPARATION
A. Clearing and Grubbing

1. All vegetation such as trees, brush, grass, roots, and deleterious material shall be disposed of offsite. This removal shall be concluded prior to placing fill.

2. Any underground structures such as cesspools, cisterns, mining shafts, tunnels, septic tanks, wells, pipe lines, etc., are to be removed or treated in a manner prescribed by the Geotechnical Consultant.
496

STANDARD GRADING SPECIFICATIONS
III. FILL AREA PREPARATION
A. Remedial Removals/Overexcavations

1. Remedial removals, as well as overexcavation for remedial purposes, shall be evaluated by the Geotechnical Consultant. Remedial removal depths presented in the geotechnical report and shown on the geotechnical plans are estimates only. The actual extent of removal should be determined by the Geotechnical Consultant based on the conditions exposed during grading. All soft, loose, dry, saturated, spongy, organic -rich, highly fractured or otherwise unsuitable ground shall be overexcavated to competent ground as determined by the Geotechnical Consultant.

2. Soil, alluvium, or bedrock materials determined by the Soils Engineer as being unsuitable for placement in compacted fills shall be removed from the site. Any material incorporated as a part of a compacted fill must be approved by the Geotechnical Consultant.

3. Should potentially hazardous materials be encountered, the Contractor should stop work in the affected area. An environmental consultant specializing in hazardous materials should be notified immediately for evaluation and handling of these materials prior to continuing work in the affected area.

B. Evaluation/Acceptance of Fill Areas
All areas to receive fill, including removal and processed areas, key bottoms, and benches, shall be observed, mapped, elevations recorded, and/or tested prior to being accepted by the Geotechnical Consultant as suitable to receive fill. The contractor shall obtain a written acceptance from the Geotechnical Consultant prior to fill placement. A licensed surveyor shall provide sufficient survey control for determining locations and elevations of processed areas, keys, and benches.

C. Processing
After the ground surface to receive fill has been declared satisfactory for support of fill by the Geotechnical Consultant, it shall be scarified to a minimum depth of 6 inches and until the ground surface is uniform and free from ruts, hollows, hummocks, or other uneven features which may prevent uniform compaction.

The scarified ground surface shall then be brought to optimum moisture, mixed as required, and compacted to a minimum relative compaction of 90 percent.

D. Subdrains
Subdrainage devices shall be constructed in compliance with the ordinances of the controlling governmental agency, and/or with the recommendations of the Geotechnical Consultant. (Typical Canyon Subdrain details are given on Plate SG -1).

E. Cut/Fill & Deep Fill/Shallow Fill Transitions
In order to provide uniform bearing conditions in cut/fill and deep fill/shallow fill transition lots, the cut and shallow fill portions of the lot should be overexcavated to the depths and the horizontal limits discussed in the approved geotechnical report and replaced with compacted fill. (Typical details are given on Plate SG -7.)
497

STANDARD GRADING SPECIFICATIONS
IV. COMPACTED FILL MATERIAL
A. General
Materials excavated on the property may be utilized in the fill, provided each material has been determined to be suitable by the Geotechnical Consultant. Material to be used for fill shall be essentially free of organic material and other deleterious substances. Roots, tree branches, and other matter missed during clearing shall be removed from the fill as recommended by the Geotechnical Consultant. Material that is spongy, subject to decay, or otherwise considered unsuitable shall not be used in the compacted fill.

Soils of poor quality, such as those with unacceptable gradation, high expansion potential, or low strength shall be placed in areas acceptable to the Geotechnical Consultant or mixed with other soils to achieve satisfactory fill material.

B. Oversize Materials
Oversize material defined as rock, or other irreducible material with a maximum dimension greater than 12 inches in diameter, shall be taken offsite or placed in accordance with the recommendations of the Geotechnical Consultant in areas designated as suitable for rock disposal (Typical details for Rock Disposal are given on Plate SG -4).

Rock fragments less than 12 inches in diameter may be utilized in the fill provided, they are not nested or placed in concentrated pockets; they are surrounded by compacted fine grained soil material and the distribution of rocks is approved by the Geotechnical Consultant.

C. Laboratory Testing
Representative samples of materials to be utilized as compacted fill shall be analyzed by the laboratory of the Geotechnical Consultant to determine their physical properties. If any material other than that previously tested is encountered during grading, the appropriate analysis of this material shall be conducted by the Geotechnical Consultant as soon as possible.

D. Import
If importing of fill material is required for grading, proposed import material should meet the requirements of the previous section. The import source shall be given to the Geotechnical Consultant at least 2 working days prior to importing so that appropriate tests can be performed and its suitability determined.

V. FILL PLACEMENT AND COMPACTION
A. Fill Layers
Material used in the compacting process shall be evenly spread, watered, processed, and compacted in thin lifts not to exceed 6 inches in thickness to obtain a uniformly dense layer.

The fill shall be placed and compacted on a horizontal plane, unless otherwise approved by the Geotechnical Consultant.
498

STANDARD GRADING SPECIFICATIONS
B. Moisture Conditioning
Fill soils shall be watered, dried back, blended, and/or mixed, as necessary to attain a relatively uniform moisture content at or slightly above optimum moisture content.

C. Compaction
Each layer shall be compacted to 90 percent of the maximum density in compliance with the testing method specified by the controlling governmental agency. (In general, ASTM D 1557- 02, will be used.)
If compaction to a lesser percentage is authorized by the controlling governmental agency because of a specific land use or expansive soils condition, the area to received fill compacted to less than 90 percent shall either be delineated on the grading plan or appropriate reference made to the area in the soils report.

D. Failing Areas
If the moisture content or relative density varies from that required by the Geotechnical Consultant, the Contractor shall rework the fill until it is approved by the Geotechnical Consultant.

E. Benching
All fills shall be keyed and benched through all topsoil, colluvium, alluvium or creep material, into sound bedrock or firm material where the slope receiving fill exceeds a ratio of 5 horizontal to 1 vertical, in accordance with the recommendations of the Geotechnical Consultant.

VI. SLOPES
A. Fill Slopes
The contractor will be required to obtain a minimum relative compaction of 90 percent out to the finish slope face of fill slopes, buttresses, and stabilization fills. This may be achieved by either overbuilding the slope and cutting back to the compacted core, or by direct compaction of the slope face with suitable equipment, or by any other procedure that produces the required compaction.

B. Side Hill Fills
The key for side hill fills shall be a minimum of 15 feet within bedrock or firm materials, unless otherwise specified in the soils report. (See detail on Plate SG -5.) C. Fill -Over -Cut Slopes
Fill -over -cut slopes shall be properly keyed through topsoil, colluvium or creep material into rock or firm materials, and the transition shall be stripped of all soils prior to placing fill. (see detail on Plate SG -6).
499

STANDARD GRADING SPECIFICATIONS
D. Landscaping
All fill slopes should be planted or protected from erosion by other methods specified in the soils report.

E. Cut Slopes

1. The Geotechnical Consultant should observe all cut slopes at vertical intervals not exceeding 10 feet.

2. If any conditions not anticipated in the preliminary report such as perched water, seepage, lenticular or confined strata of a potentially adverse nature, unfavorably inclined bedding, joints or fault planes are encountered during grading, these conditions shall be evaluated by the Geotechnical Consultant, and recommendations shall be made to treat these problems (Typical details for stabilization of a portion of a cut slope are given in Plates SG -2 and SG -3.).

3. Cut slopes that face in the same direction as the prevailing drainage shall be protected from slope wash by a non -erodible interceptor swale placed at the top of the slope.

4. Unless otherwise specified in the soils and geological report, no cut slopes shall be excavated higher or steeper than that allowed by the ordinances of controlling governmental agencies.

5. Drainage terraces shall be constructed in compliance with the ordinances of controlling governmental agencies, or with the recommendations of the Geotechnical Consultant.

VII. GRADING OBSERVATION
A. General
All cleanouts, processed ground to receive fill, key excavations, subdrains, and rock disposals must be observed and approved by the Geotechnical Consultant prior to placing any fill. It shall be the Contractor's responsibility to notify the Geotechnical Consultant when such areas are ready.

B. Compaction Testing
Observation of the fill placement shall be provided by the Geotechnical Consultant during the progress of grading. Location and frequency of tests shall be at the Consultants discretion based on field conditions encountered. Compaction test locations will not necessarily be selected on a random basis. Test locations may be selected to verify adequacy of compaction levels in areas that are judged to be susceptible to inadequate compaction.

C. Frequency of Compaction Testing
In general, density tests should be made at intervals not exceeding 2 feet of fill height or every 1000 cubic yards of fill placed. This criteria will vary depending on soil conditions and the size of the job. In any event, an adequate number of field density tests shall be made to verify that the required compaction is being achieved.
500

STANDARD GRADING SPECIFICATIONS
VIII. CONSTRUCTION CONSIDERATIONS
A. Erosion control measures, when necessary, shall be provided by the Contractor during grading and prior to the completion and construction of permanent drainage controls.

B. Upon completion of grading and termination of observations by the Geotechnical Consultant, no further filling or excavating, including that necessary for footings, foundations, large tree wells, retaining walls, or other features shall be performed without the approval of the Geotechnical Consultant.

C. Care shall be taken by the Contractor during final grading to preserve any berms, drainage terraces, interceptor swales, or other devices of permanent nature on or adjacent to the property.

S:\!BOILERS-WORK\REPORT INSERTS \ STANDARD GRADING SPECS 501

TYPICAL BENCHING

DEPTH AND BEDDING MAY

VARY WITH P PE AND LOAD
CHARACTERISTICS.
(3' TYPICAL)

NATURAL GROUND

PROPOSED GRADE
.1/

PROPOSED COMPACTED FILL
REMOVE

UNSUITABLE

MATERIAL

UVIUM, COLLUVIUM

COMPETENT NATIVE SOIL

OR BEDROCK MATERIALS,

AS DETERMINED BY THE

GEOTECHNICAL''

CONSULTANT
h SUBDRAIN SYSTEM -
�� 9 CUBIC FEET PER LINEAL FOOT
y OF OPEN -GRADED GRAVEL
ENCASED IN FILTER FABRIC.

SEE PLATE SG -3 FOR OPEN -
'GRADED GRAVEL SPECIFICATIONS.

FILTER FABRIC SHALL CONSIST
OF MIRAFI 140N OR APPROVED -
EQUIVALENT. FILTER FABRIC
`SHOULD BE LAPPED A MINIMUM
:OF 12 INCHES.

ALTERNATE SUB0RAIN SYSTEM -
MINIMUM OF 9 CUBIC FEET PER
LINEAL FOOT OF CLASS 2 FILTER
MATERIAL. SEE PLATE SG -3 FOR
CLASS 2 FILTER MATERIAL
SPECIFICATIONS. CLASS 2

MATERIAL DOES NOT NEED TO BE
`ENCASED INFIL I ER FABRIC.

MINIMUM 6 -INCH DIAMETER PVC SCHEDULE 40, OR ABS SDR-35 WITH A MINIMUM OF EIGHT 1/4 -INCH DIAMETER PERFORATIONS PER LINEAL FOOT IN BOTTOM HALF OF PIPE. PIPE TO BE LAID WITH PERFORATIONS FACING DOWN.

NOTES:

1. FOR CONTINUOUS RUNS IN EXCESS OF 500 FEET USE 8 -INCH DIAMETER PIPE.

2. FINAL 20 FEET OF PIPE AT OUTLET SHALL BE NON -PERFORATED AND BACKFILLED WITH FINE-GRAINED MATERIAL.

T
CANYON6ICTLAIN DETAIL
PLATE SG -1

OVEREXCAVATE PAD

AS RECOMMENDED BY

GEOTECHNICAL CONSULTANT
OUTLETS TO BE SPACED AT 100' MAX. INTERVALS.

EXTEND 12" BEYOND FACE OF SLOPE AT TIME OF
ROUGH GRADING CONSTRUCTION. PROVIDE
GRATES TO PREVENT RODENT NESTING.

FINISHED
GRADE

PROPOSED GRADE
15' MINIMUM

TO TOP OF BACKCUT
.-4" NON -PERFORATED SUBDRAIN'

COMPETENT

NATIVE MATERIAL

TYPICAL BENCHING
4" NON -PERFORATED SUBDRAIN ' 4'TYPICAL
15' MINIMUM

KEY WIDTH
2' MIN. KEY DEPTH INTO COMPETENT

BEDROCK OR COMPETENT SOIL

MATERIALS AS DETERMINED BY THE

GEOTECHNICAL CONSULTANT

OUTLET PIPE (TYPICAL)

VARIABLE
(10' TYPICAL).::

NOTES:

1. 30' MAXIMUM VERTICAL SPACING BETWEEN SUBDRAIN SYSTEMS.

2. T00' MAXIMUM HORIZONTAL DISTANCE BETWEEN NON -PERFORATED OUTLET PIPES. (See Below)

3. MINIMUM GRADIENT OF 2% FOR ALL PERFORATED AND NON -PERFORATED PIPE.

SECTION A -A (PERFORATED PIPE PROFILE)
100' max.
50' _

PERFORATED PIPE (TYPICAL)
>I4- 50'

OUTLET PIPE (TYPICAL)
T

BUTTRESS OR STABILIZATION
F5 TAIL
PLATE SG -2

SLOPE FACE
12" min.
14-12" min. -3"
;4 -INCH NON -PERFORATED PIPE.

MINIMUM 2% GRADE TO OUTLET.

APPROVED FILTER MATERIAL (OPEN -

GRADED GRAVEL WRAPPED IN FILTER
FABRIC OR CLASS 2 FILTER MATERIAL).
5 CUBIC FEET OF CLASS 2 FILTER
• MATERIAL, WITHOUT FILTER FABRIC.
•
-OR-
• 3 CUBIC FEET OF OPEN -GRADED GRAVEL
PER LINEAR FOOT WITH FILTER FABRIC.

FILTER FABRIC SHOULD CONSIST OF
MIRAFI 140N OR EQUIVALENT, AND

SHOULD BE LAPPED A MINIMUM OF
• 12 INCHES
4 -INCH PERFORATED PIPE WITH
PERFORATIONS DOWN. MINIMUM
2% GRADE TO OUTLET PIPE.

APPROVED ON -SITE MAI ERIAL PER SOILS ENGINEER
COMPACTED TO A MINIMUM OF 90% MAXIMUM DENSITY.
4 -INCH NON -PERFORATED PIPE

SECTION B -B (OUTLET PIPE)
PIPE SPECIFICATIONS:

1. 4 -INCH MINIMUM DIAMETER, PVC SCHEDULE 40 OR ABS SDR-35.

2. FOR PERFORATED PIPE, MINIMUM 8 PERFORATIONS PER FOOT ON BOTTOM HALF OF PIPE.

OPEN -GRADED GRAVEL ENCASED IN FILTER FABRIC.
(MIRAFI 140N OR EQUIVALENT)

OPEN -GRADED GRAVEL

SIEVE SIZE PERCENT PASSING
1 1/2 -INCH 88 - 100
1 -INCH 5 - 40
3/4 -INCH 0 - 17
3/8 -INCH 0 - 7
No. 200 0 - 3
ALTERNATE:

CLASS 2 PERMEABLE FILTER MATERIAL PER CALTRANS
STANDARD SPECIFICATION 68-1.025.

CLASS 2 FILTER MATERIAL

SIEVE SIZE PERCENT PASSING
1 -INCH 100
3/4 -INCH 90 - 100
3/8 -INCH 40 - 100
No.4 25-40
No.8 18-33
No. -30 5 - 15
No. -50 0 - 7
No. 200 0 - 3

BUTTRESS OR STABILIZATION
Ft 4DRA1N
PLATE SG -3

FINISHED GRADE

SLOPE FACE
10' CLEAR AREA FOR FOUNDATIONS,

UTILITIES AND SWIMMING POOLS
NOM: OVERSIZE ROCK IS DEFINED AS CLASTS HAVING A MAXIMUM DIMENSION OF 12" OR LARGER

WINDROW COMPACTED FILL
15'
�:•:'.•:;::; ;•:.•,i {'•.{':::':.:,'::'•;'•;: c;{.'•;:';.:::•.:'•:';`r;'�:'•'::•:••:'•;;:� ` MIN �

TYPICAL WINDROW DETAIL (END VIEW)

GRANULAR SOIL JE I I ED OR FLOODED

TO FILL VOIDS

COMPACTED FILL

PLACED IN
.6 TO8-INCH-THICK...:.::

HORIZONTAL LIFTS
15' MIN.

STREET
5' OR MIN. OF 2' BELOW DEPTH

OF DEEPEST UTILITY TRENCH,

WHICHEVER IS GREATER

TYPICAL WINDROW DETAIL (PROFILE VIEW)
Jt I I ED OR FLOODED GRANULAR SOIL
T
TYPICAL RngSPOSAL DETAIL
PLATE SG -4

TOE OF SLOPE AS SHOWN

ON GRADING PLAN

PLACE COMPACTED

FILL TO NATURAL

SLOPE GRADE

EXISTING
GROUND

SURFACE
♦

PROPOSED GRADE

REMOVE UNSUITABLE

MATERIAL
15' MINIMUM '

KEY WIDTH
2' MIN. KEY DEPTH INTO COMPETENT

BEDROCK OR SOIL MATERIALS AS
DETERMINED BY THE GEOTECHNICAL:

CONSULTANT
,1110,0010.1.1. MOO= 1001.01110. faillWROVAIS
00/

COMPACTED FILL

TYPICAL BENCHING

COMPETENT BEDROCK OR SOIL MATERIALS

AS DETERMINED BY THE

GEOTECHNICAL CONSULTANT
MAINTAIN 15' MIN. HORIZONTAL WIDTH
FROM SLOPE FACE TO BENCH I BACKCUT �.`.

NOTES:

1. WHERE NATURAL SLOPE GRADIENT IS 5:1 OR LESS, BENCHING IS NOT NECESSARY; HOWEVER, FILL IS NOT TO BE PLACED ON COMPRESSIBLE OR UNSUITABLE MATERIAL.

2. SOILS ENGINEER TO DETERMINE IF SUBDRAIN IS REQUIRED.

T
FILL SLOPE ng NATURAL SLOPE
PLATE SG -5

CUT / F LL CONTACT

SHOWN ON GRADING PLAN

SHOWN ON AS -BUILT

REMOVE UNSUITABLE

MATERIAL

NATURAL GROUND

SURFACE
CUT
ALLUVIUM.

PROPOSED GRADE
4' TYP.
•
Bin

VARIABLE
10' TYPICAL
COMPETENT BEDROCK OR SOIL MATERIALS.

AS De! LRMINED BY THE

GEOTECHNICAL CONSULTANT
MAINTAIN 15' MIN. HORIZONTAL WIDTH
:FROM SLOPE FACE TO BENCH I BACKCUT

INSTALLATION OF SUBDRAIN TO BE DETERMINED
BY THE GEOTECHNICAL CONSULTANT.

IF REQUIRED, SEE PLATES SG -2 AND SG -3
FOR TYPICAL SUBDRAIN DETAILS.

THE CUT PORTION OF THE SLOPE SHOULD BE EXCAVATED

AND EVALUATED BY THE ENGINEERING GEOLOGIST PRIOR
`TO CONSTRUCTING THE FILL PORTION OF THE SLOPE.

FILL SLOarOVE CUT SLOPE
PLATE SG -6

CUT LOT

UNSUITABLE MATERIAL EXPOSED IN PORTION OF CUT PAD

ORIGINAL GROUND

SURFACE
REMOVE

UNSUITABLE

MATERIAL
REMOVE

UNSUITABLE

MATERIAL
— 1
(D) or
145 MIN.,
OPgpiL:;:

NSI
;.TYPICAL BENCHING.
r ^ i
r i
r- , �
- PROPOSED GRADE
ALLUV{UM.

COLLUVIUM,
WFAmERFD
OCK
(D) or
I�5' MIN.> •
t(D)

OVEREXCAVATE AND RECOMPACT,

COMPETENT BEDROCK OR SOIL MATERIALS

AS DETERMINED BY THE

GEOTECHNICAL CONSULTANT
r ORIGINAL GROUND

SURFACE

PROPOSED GRADE
51 TYPICAL BENCHING: -
(D) or
5'
MIN. `J
VEREXCAVATE AND RECOMPACT.

COMPETENT BEDROCK OR SOIL MATERIALS

AS DETERMINED BY THE

GEOTECHNICAL CONSULTANT

MAXIMUM FILL THICKN SS (F) DEPTH OF OVEREXCAVATION (D)
FOOTING DEPTH TO 3 FEET EQUAL DEPTH
3 TO 6 FEET 3 FEET
GREATER THAN 6 FEET 1/2 THE THICKNESS OF DEEPEST FILL PLACED WITHIN THE "FILL" PORTION (F) TO 15 FEET MAXIMUM
CUT _O ` S * ND CUT -FILL
T

ON LOTS
PLATE SG -7

D = RECOMMENDED DEPTH OF REMOVAL

PER GEOTECHNICAL REPORT
:REMOVE

UNSUITABLE
:MATERIAL
PROPOSED 2:1 FILL SLOPE

EXISTING GROUND SURFACE

TYPICAL BENCHING INTO
<:;COMPETENT BEDROCK OR

SOIL MATERIALS AS

DETERMINED BY THE

GEOTECHNICAL CONSULTANT

DESIRED REMOVAL

LIMITS BEYOND TOE
15' MINIMUM KEY WIDTH
:..EMBEDDED A MINIMUM OF 2'

INTO COMPETENT BEDROCK
.',:OR SOIL MATERIALS AS

DETERMINED BY THE

GEOTECHNICAL CONSULTANT
2D

PLACE COMPACTED

FILL TO NATURAL

SLOPE GRADE
T

TYPICAL REV ,LS BEYOND TOE
OF PRC5 E' FILL SLOPE
PLATE SG -8

EXISTING GROUND SURFACE
PROPOSED CUT LOT i PROPOSED DAYLIGHT CUT
NOTE:

1. "D" SHALL BE 10 FEET MINIMUM OR AS DETERMINED BY SOILS ENGINEER.

RECONSTRUCT AT 2:1

OR FLATTER
,,INSTALL 4 -INCH SUBDRAIN.�
.SEE PLATES SG -2 AND SG -3

FOR TYPICAL SUBDRAIN

APPENDIX C

PRELIMINARY TITLE REPORT
511

Fidelity National Title
• BUILDER SERVICES
4210 Riverwalk Parkway, Suite 100
Riverside, CA 92505
Phone: (951) 710-5944
Fax: (951) 710-5955
Issuing Policies of Fidelity National Title Insurance Company Order No.: 010-30112060-A-BAM
TO:

National Community Renaissance
9421 Haven Avenue
Rancho Cucamonga, CA 91730
ATTN: Alexa Washburn
YOUR REFERENCE:

Main Office Line: (949) 622-5000
Title Officer: Andrew Margo (BS-RIV)
Title Officer Phone: (951) 710-5944
Title Officer Fax: (951) 710-5955
Title Officer Email: [email protected]
PROPERTY ADDRESS: Vacant Land, Rancho Mirage, CA

AMENDED PRELIMINARY REPORT
In response to the application for a policy of title insurance referenced herein, Fidelity National Title Company hereby reports that it is prepared to issue, or cause to be issued, as of the date hereof, a policy or policies of title insurance describing the land and the estate or interest therein hereinafter set forth, insuring against loss which may be sustained by reason of any defect, lien or encumbrance not shown or referred to as an exception herein or not excluded from coverage pursuant to the printed Schedules, Conditions and Stipulations or Conditions of said policy forms.

The printed Exceptions and Exclusions from the coverage and Limitations on Covered Risks of said policy or policies are set forth in Attachment One. The policy to be issued may contain an arbitration clause. When the Amount of Insurance is less than that set forth in the arbitration clause, all arbitrable matters shall be arbitrated at the option of either the Company or the Insured as the exclusive remedy of the parties. Limitations on Covered Risks applicable to the CLTA and ALTA Homeowner's Policies of Title Insurance which establish a Deductible Amount and a Maximum Dollar Limit of Liability for certain coverages are also set forth in Attachment One.

Copies of the policy forms should be read. They are available from the office which issued this report.

This report (and any supplements or amendments hereto) is issued solely for the purpose of facilitating the issuance of a policy of title insurance and no liability is assumed hereby. If it is desired that liability be assumed prior to the issuance of a policy of title insurance, a Binder or Commitment should be requested.

The policy(s) of title insurance to be issued hereunder will be policy(s) of Fidelity National Title Insurance Company, a Florida Corporation.

Please read the exceptions shown or referred to herein and the exceptions and exclusions set forth in Attachment One of this report carefully. The exceptions and exclusions are meant to provide you with notice of matters which are not covered under the terms of the title insurance policy and should be carefully considered.

It is important to note that this preliminary report is not a written representation as to the condition of title and may not list all liens, defects and encumbrances affecting title to the land.

Countersigned by:

C? -
Authorized Signature
CLTA Preliminary Report Form — Modified (11/17/06
12

Page 1 ends

Rancho Mirage City CouncilJuly 17, 2025

Rancho Mirage City Council
July 17, 2025