Moreno Valley City Council
June 3, 2025

GEOTECHNICAL EXPLORATION

TOWN CENTER AT MORENO VALLEY

NORTHWEST CORNER OF ALESSANDRO BLVD AND

NASON STREET

MORENO VALLEY, CALIFORNIA

Prepared for

LEWIS LAND DEVELOPERS, LLC
1156 North Mountain Avenue
Upland, California 91786

Project No.
13177.002

July 23, 2021
Revised January 17, 2025
~ Leighton
a verdantas company
July 23, 2021
Revised January 17, 2025
Project No. 13177.002
Lewis Land Developers, LLC
1156 North Mountain Avenue
Upland, California 91786
Attention: Mr . Joseph Edwards Bill Hoover, Vice President-Regional Planned Communities
Subject: Geotechnical Exploration
Town Center at Moreno Valley
Northwest Corner of Alessandro Blvd and Nason Street
Moreno Valley, California
In accordance with your request, we are pleased to present this geotechnical exploration report for the subject project . This report presents our findings, conclusions and recommendations pertaining to the geotechnical aspects of the proposed development.

It is our opinion that the overall site appears suitable for the intended use provided our recommendations included herein are properly incorporated during design and construction phases of development.

If you have any questions regarding this report, please do not hesitate to contact the undersigned. We appreciate this opportunity to be of service on this project.

Respectfully submitted,
LEIGHTON AND ASSOCIATES, INC.

Simon I. Saiid, GE 2641
Principal Engineer
Robert F. Riha, CEG 1921
Sr. VP / Sr. Principal Geologist
Distribution: (1) A ddressee (PDF copy)
~ Leighton --a verdantas company
41715 Enterprise Circle N, Suite 103, Temecula, CA 92590 www.leightongroup.com
Leighton and Associates, Inc.

T: 951 .296.0530
Geotechnical Exploration 13177.002
Town Center at Moreno Valley, Moreno Valley, California July 23, 2021 Revised January 17, 2025

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TABLE OF CONTENTS
Section Page

1.1 Purpose and Scope ............................................................................................. 1

1.2 Site Location and Description ............................................................................. 1

1.3 Proposed Development ....................................................................................... 2

2.1 Fie
ld Exploration .................................................................................................. 3

2.2 Laboratory Testing .............................................................................................. 3

3.1 Regi
onal Geology ................................................................................................ 4

3.2 Site Specific Geology .......................................................................................... 4

3.2.1 Artificial Fill (Stockpile) ......................................................................................... 4

3.2.2 Alluvial Deposits ................................................................................................... 4

3.3 Landslide/Debris Flow and Rock Fall .................................................................. 5

3.4 Rippability ............................................................................................................ 5

3.5 Groundwater and Surface Water ........................................................................ 5

3.6 Faulting ................................................................................................................ 5

3.7 Ground Shaking .................................................................................................. 5

3.8 Dynamic Settlement (Liquefaction and Dry Settlement) ..................................... 6

3.9 Expansive Soils ................................................................................................... 6

3.10 Slope Stability ...................................................................................................... 6

3.11 Percolation/Infiltration Testing ............................................................................. 7

4.1 Gen
eral ................................................................................................................ 8

4.2 Earthwork ............................................................................................................ 8

4.2.1 Site Preparation and Remedial Grading ............................................................. 8

4.2.2 Suitability of Site Soils for Fills ............................................................................. 9

4.2.3 Shrinkage ............................................................................................................. 9

4.2.4 Import Soils ........................................................................................................ 10

4.2.5 Utility Trenches .................................................................................................. 10

4.2.6 Drainage ............................................................................................................ 10

4.2.7 Slope Construction ............................................................................................ 10

4.3 Foundation Design ............................................................................................ 11

4.3.1 Bearing and Lateral Pressures .......................................................................... 11

4.4 Retaining Walls ................................................................................................. 12

4.5 Foundation Setback from Slopes ...................................................................... 13

4.6 Sulfate Attack .................................................................................................... 13

4.7 Concrete Flatwork ............................................................................................. 14

4.8 Preliminary Pavement Design ........................................................................... 14

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

2.0 FIELD EXPLORATION AND LABORATORY TESTING ....................................... 3

3.0 GEOTECHNICAL AND GEOLOGIC FINDINGS .................................................... 4

4.0 CONCLUSIONS AND RECOMMENDATIONS ...................................................... 8 ~ Leighton
a verdantas company
Geotechnical Exploration 13177.002
Town Center at Moreno Valley, Moreno Valley, California July 23, 2021 Revised January 17, 2025

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Accompanying Tables, Figures, Plates and Appendices
Tables
Table 1. CBC Site-Specific Seismic Coefficients ............................................................ 6 Table 2. Summary of Percolation/Infiltration Test Results .............................................. 7 Table 3. Conventional Foundation Requirements ........................................................ 12 Table 4. Retaining Wall Design Earth Pressures (Static, Drained) ............................... 12 Table 5. Footing Setbacks ............................................................................................ 13 Table 6. Asphalt Pavement Sections............................................................................ 14

Figures
Figure 1 – Site Location Map Rear of Text
Figure 2 – Boring Location Plan Rear of Text
Figure 3 – Regional Geology Map Rear of Text
Figure 4 – Liquefaction Hazard Map Rear of Text

Appendices
Appendix A – Field Exploration / Logs of Borings
Appendix B – Geotechnical Laboratory Test Results
Appendix C – Earthwork and Grading Specifications
Appendix D – GBA Important Information About This Geotechnical Engineering Report

5.0 GEOTECHNICAL CONSTRUCTION SERVICES ................................................ 16

6.0 LIMITATIONS ....................................................................................................... 17 REFERENCES .............................................................................................................. 18 ~ Leighton
a verdantas company
Geotechnical Exploration 13177.002
Town Center at Moreno Valley, Moreno Valley, California July 23, 2021 Revised January 17, 2025

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INTRODUCTION

1.1 Purpose and Scope
This geotechnical exploration report is for the Town Center at Moreno Valley project located at the Northwest Corner of Alessandro Blvd and Nason Street, in Moreno Valley, California (see Figure 1). Our scope of services for this geotechnical exploration included the following:

 Review of available site- specific reports and published data, including various geologic publications listed in the references at the end of this report.  A review of the provided site plan.
 Site reconnaissance and visual observations of surface conditions to evaluate any potential localized settlement or other surface distresses.  Excavation of eight (8) geotechnical borings and four (4 ) percolation-infiltration tests to explore the subsurface soil conditions within the site . Approximate locations of these explorations are depicted on Figure 2. The logs of borings and percolation tests are included in Appendix A.
 Laboratory testing was performed on representative samples and results are included in Appendix B.
 Geotechnical engineering analyses performed or as directed by a California registered Geotechnical Engineer (GE) . A California Certified Engineering Geologist (CEG) performed engineering geology review of site geologic hazards.  Preparation of t his update report, which presents the results of our geotechnical exploration and preliminary recommendation for site development.

This report is not intended to be used as an environmental assessment (Phase I or other), and foundation and/or a rough grading plan review.

1.2 Site Location and Description
Based on information provided, the approximately 69.6-acre site is tentatively planned to be developed into a mixed residential (36 acres), commercial (16 acres in the south), and park (4.9 acres). The overall property consists of the following APNs: 487-470-030, 487- 470-031, and future Bay Avenue ROW. The site is currently undeveloped with a large stockpile of fill in the southeastern corner. Small vegetation growth including weeds and seasonal grasses cover most of the site. The site topography slopes gently into southwesterly direction. Site elevations vary from approximately 1590 feet MSL (Mean Sea Level) in the southwest corner to a maximum elevation of approximately 1640 feet MSL in the northeast corner of the site.

1.0 ~ Leighton
a verdantas company
Geotechnical Exploration 13177.002
Town Center at Moreno Valley, Moreno Valley, California July 23, 2021 Revised January 17, 2025

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1.3 Proposed Development
Based on the provided site plan (WHA), we understand the residential development will consist of approximately 800 units within up to 3 -story multi-family residential buildings consisting of wood -frame structures with conventional slab-on-grade foundations. The foundation loads are not expect ed to exceed 2,5 00 pounds per lineal foot (plf) for continuous footings. We also expect the loading and foundation requirements for the non- residential portion of the site to be substantially similar. We anticipate site grading will require maximum cuts and fills on the order of ±10 feet. If site development differs significantly from the assumptions stated herein, our recommendations should be subject to further reviews and evaluations.

~ Leighton
a verdantas company
Geotechnical Exploration 13177.002
Town Center at Moreno Valley, Moreno Valley, California July 23, 2021 Revised January 17, 2025

- 3 -

FIELD EXPLORATION AND LABORATORY

TESTING

2.1 Field Exploration
Our field exploration consist ed of the excavation of eight (8) borings and four (4 ) percolation/infiltration tests within accessible areas of the site. During excavation, bulk samples and relatively “undisturbed” Ring samples were collected from the exploration borings for further laboratory testing and evaluation. Approximate locations of the borings and percolation/infiltration tests are depicted on the Boring Location Plan ( Figure 2).

Sampling was conducted by a staff engineer from our firm. After logging and sampling, the excavations were loosely backfilled with spoils generated during excavation.

The exploration logs included within Appendix A and related information depicts subsurface conditions only at the locations indicated and at the particular date designated on the logs. Subsurface conditions at other locations may differ from conditions occurring at these borings locations. The passage of time may result in altered subsurface conditions due to environmental changes. In addition, any stratification lines on the logs represent the approximate boundary between soil types and the transition may be gradual.

2.2 Laboratory Testing
Laboratory tests were performed on representative bulk samples to provide a basis for development of remedial earthwork and geotechnical design parameters. Selected samples were tested to determine the following parameters: maximum dry density and optimum moisture, expansion index , soluble sulfate content, gradation and collapse potential. The results of our laboratory testing are presented in Appendix B.

2.0 ~ Leighton
a verdantas company
Geotechnical Exploration 13177.002
Town Center at Moreno Valley, Moreno Valley, California July 23, 2021 Revised January 17, 2025

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GEOTECHNICAL AND GEOLOGIC FINDINGS

3.1 Regional Geology
The site is located within a prominent natural geomorphic province in southwestern California known as the Peninsular Ranges. It is characterized by steep, elongated ranges and valleys that trend northwestward. More specifically, the site is situated within the Perris Block, an eroded mass of Cretaceous and older crystalline rock.

The Perris Block, approximately 20 miles by 50 miles in extent, is bounded by the San Jacinto Fault Zone to the northeast, the Elsinore Fault Zone to the southwest, the Cucamonga Fault Zone to the northwest, and the Temecula Basin to the southeast. The southeast boundary of the Perris block is poorly defined. The Perris Block has had a complex tectonic history, apparently undergoing relative vertical land movements of several thousand feet in response to movement on the Elsinore and San Jacinto Fault Zones. Thin sedimentary and volcanic materials locally mantle the crystalline bedrock. Alluvial and colluvial deposits fill the lower valley areas. Based on published geologic maps (see Figure 3), the site is underlain by young and very old fan deposits.

3.2 Site Specific Geology
The geologic units encountered are discussed in the following sections in order of increasing age and further described on the logs of borings in Appendix A.

3.2.1 Artificial Fill (Stockpile)
A large stockpile of artificial fill is located at the southeastern corner of the site.

The source of these materials is not known to us, however the soils app ear to substantially similar to the soils explored in the borings. Additionally, artificial fill was encountered in some of our borings in the upper 12 to 24 inches of site soils, which appear to be the result of previous site grading or agricultural activities. The suitability of the stockpile soils to be used as fill materials during grading should be further evaluated during grading.

3.2.2 Alluvial Deposits
The alluvial fan deposits were observed throughout the site to the depths explored of 51 feet below ground surface. As encountered, th ese soils typically consisted of brown to reddish brown, medium dense to very dense, moist silty sand (SM) and well-graded sand with variable amounts of silt (SW-SM) and interbedded low- plasticity sandy silt (ML) layers. This alluvium is expected to generally possess a very low expansion potential (EI<21). Our laboratory testing indicates the upper 5 to 10 feet of alluvium has a slight to moderate collapse potential (<6%).

3.0 ~ Leighton
a verdantas company
Geotechnical Exploration 13177.002
Town Center at Moreno Valley, Moreno Valley, California July 23, 2021 Revised January 17, 2025

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3.3 Landslide/Debris Flow and Rock Fall
No evidence of on- site landslides/debris flow or rock fall was observed during our field investigation and review of referenced reports. Elevated topography and thick deposits of surficial soils typically associated with landsliding or debris flows are not present. Due to the lack of nearby rock outcrop and the gentle natural slope of adjacent hillside areas, the debris flow and rock fall hazard is considered very low.

3.4 Rippability
Based on the results of our geotechnical borings, previous experience in this area, we do not anticipate that bedrock be encountered during site work within the upper 50 feet below ground surface (BGS)

3.5 Groundwater and Surface Water
Groundwater was not encountered during this exploration to the depths explored (51.5 feet). Recent groundwater level was measured in March 2021 at approximately 1470 feet MSL (approximately 40 feet BGS) at well EMWD25695 (339025N1171928W001), which is approximately one- mile south of the site. Thus, we do not anticipate significant groundwater related problems during grading or future development . However, locally perched water conditions can occur and may fluctuate seasonally, depending on rainfall. No surface water was observed.

3.6 Faulting
No indications of faulting or fault related fissuring or fracturing is known to exist or observed onsite. T his site is not located within a currently designated Alquist -Priolo Earthquake Fault Zone or County of Riverside Fault Zone.

3.7 Ground Shaking
Strong ground shaking can be expected at the site during moderate to severe earthquakes in this general region. This is common to virtually all of Southern California.

Intensity of ground shaking at a given location depends primarily upon earthquake magnitude, site distance from the source, and site response (soil type) characteristics.

The site-specific seismic coefficients provided in this section are based on an interactive tools/programs currently available on USGS website and OSHPD seismic maps. Based on ASCE 7 -16 and our site- specific ground motion analysis for this Class D site, the seismic coefficients for this site are as listed in Table 1 below:
~ Leighton
a verdantas company
Geotechnical Exploration 13177.002
Town Center at Moreno Valley, Moreno Valley, California July 23, 2021 Revised January 17, 2025

- 6 -
Table 1. CBC Site-Specific Seismic Coefficients
CBC Categorization/Coefficient Value (g)
Site Longitude (decimal degrees) -117.1940
Site Latitude (decimal degrees) 33.9208
Site Class Definition D
Mapped Spectral Response Acceleration at 0.2s Period, Ss 1.87 Mapped Spectral Response Acceleration at 1s Period, S1 0.74 Short Period Site Coefficient at 0.2s Period, Fa 1.0
Long Period Site Coefficient at 1s Period, Fv 1.7
Adjusted Spectral Response Acceleration at 0.2s Period, SMS 1.87 Adjusted Spectral Response Acceleration at 1s Period, SM1 1.25 Design Spectral Response Acceleration at 0.2s Period, SDS 1.25 Design Spectral Response Acceleration at 1s Period, SD1 0.83 Site-Specific Modified Peak Ground Acceleration, PGAm 0.87 Note: The seismic coefficients for Site Class D follows Exception (2) in Section 11.4.8 of ASCE 7-16 that assumes a fundamental period of vibration less than 0.5s for the proposed structures. The project structural engineer should confirm such assumption or else a site–specific ground motion analysis will be required

3.8 Dynamic Settlement (Liquefaction and Dry Settlement) Ground movements generated during a seismic event can produce settlements in sands or granular earth materials both above and below the water table. The earth materials onsite may experience seismically induced settlement during the design seismic event.

The potential for such seismic densification to manifest at the graded surface and impact the development site is low to moderate.

If remedial grading is performed as recommended, total dynamic densification settlement is estimated to be less than 2 inches globally with anticipated differential settlement of 1- inch in 40 feet.

3.9 Expansive Soils
Limited laboratory testing indicated that near surface soils generally possess a very low expansion potential.

3.10 Slope Stability
It is anticipated that slopes constructed within the site are to be less than 15 feet in height.

If constructed at 2:1 gradient using onsite soils, these slopes should be grossly stable under short- and long-term conditions (including seismic loading). ~ Leighton
a verdantas company
Geotechnical Exploration 13177.002
Town Center at Moreno Valley, Moreno Valley, California July 23, 2021 Revised January 17, 2025

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3.11 Percolation/Infiltration Testing
Percolation tests and associated test borings were performed in the vicinity of the proposed basins on the center-right and lower-right sections of the site (see Figure 2). Testing was performed in general accordance with the procedures of the Riverside County Flood Control and Water Conservation District (RCFC&WCD) Design Handbook (RCFC, 2011).

The percolation tests (P-1 through P-4) were performed to depths of approximately 5 to 7 feet BGS. Adjacent deeper borings indicate the presence of silty sands to well-graded sands with silts to depths of at least 12 feet BGS. The results of the percolation testing are presented below. A factor of safety has not been applied to these rates.

Table 2. Summary of Percolation/Infiltration Test Results Test
Hole # Location Depth
BGS (ft)
Percolation
Rate (min/in)
Infiltration
Rate
(in/hr)
Soil Description
P-1 See Fig 2 7 1.0 2.9 Silty Sand (SM)
P-2 See Fig 2 5 0.7 4.1 Silty Sand (SM)
P-3 See Fig 2 5 1.5 1.5 Silty Sand (SM)
P-4 See Fig 2 5 0.7 3.5 Silty Sand (SM)

I I I I
~ Leighton
a verdantas company
Geotechnical Exploration 13177.002
Town Center at Moreno Valley, Moreno Valley, California July 23, 2021 Revised January 17, 2025

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CONCLUSIONS AND RECOMMENDATIONS

4.1 General
Development of the site appears feasible from a geotechnical viewpoint provided that the following recommendations are incorporated into the design and construction phases of development.

4.2 Earthwork
Earthwork should be performed in accordance with the following recommendations and the Earthwork and Grading Specifications Appendix C. The recommendations contained in Appendix C, are general grading specifications provided for typical grading projects and some of the recommendations may not be strictly applicable to this project. The specific recommendations contained in the text of this report supersede the general recommendations in Appendix C . The contract between the developer and earthwork contractor should be worded such that it is the responsibility of the contractor to place the fill properly in accordance with the recommendations of this report, the specifications in Appendix C , applicable C ity Grading Ordinances, notwithstanding the testing and observation of the geotechnical consultant.

4.2.1 Site Preparation and Remedial Grading
Prior to grading, the proposed structural improvement areas (i.e. all structural fill areas, pavement areas, buildings, etc.) of the site should be cleared of surface and subsurface obstructions, heavy vegetation, and/or deleterious materials . Roots and debris should be disposed of offsite. Septic tanks or seepage pits, if encountered, should be abandoned in accordance with the County of Riverside Department of Health Services guidelines.

Compressible materials including; undocumented fill, surficial topsoil, and near surface alluvial deposits are potentially compressible in their present state and may settle under the surcharge of fills or foundation loading. As such , these materials should be removed and re- compacted to a minimum of 90 percent relative compaction (based on ASTM D1557) . F or preliminary planning purposes, the anticipated removal depth is expected to extend to a depth of 6 feet BGS in the northern portion of the site (or north of LB-3), 8 feet in the middle portion of the site (or between LB-4 and LB-5) and 10 feet south of LB -6. The removal limit should be established by a 1:1 (H:V) projection from the edge of fill soils supporting settlement-sensitive structures downward and outward to competent material identified by the geotechnical consultant. Cut slopes exposing alluvial soils greater than 3 feet in height should be removed and replaced as compacted fill slopes in accordance with Appendix C. Removals will also include benching into competent material as the fills rise. Areas adjacent to existing structures, property boundary

4.0 ~ Leighton
a verdantas company
Geotechnical Exploration 13177.002
Town Center at Moreno Valley, Moreno Valley, California July 23, 2021 Revised January 17, 2025

- 9 -
and roadways, may require special monitoring. Temporary cuts in these areas should be no steeper than 1 :1 slopes. Deeper removal may be required in localized areas depending on recommendations by the geotechnical consultant.

4.2.2 Suitability of Site Soils for Fills
The onsite soils are generally suitable for re -use as compacted fill, provided they are free of debris and organic matter. Fills placed within 10 feet of finish pad grades or slope faces should contain no rocks over 12 inches in maximum dimension. If encountered, clayey soils layers (EI>51) should be placed at depth greater than 5 feet below finished grades where feasible. All structural fill should be compacted throughout to 90 percent of the ASTM D 1557 laboratory maximum density, at or slightly above optimum moisture.

Fill soils should be placed at a minimum of 90 percent relative compaction (based on ASTM D1557) and near or above optimum moisture content. Placement and compaction of fill should be performed in accordance with local grading ordinances under the observation and testing of the geotechnical consultant. The optimum lift thickness to produce a uniformly compacted fill will depend on the type and size of compaction equipment used. In general, fill should be placed in uniform lifts not exceeding 8 inches in thickness.

Fill slope keyways will be necessary at the toe of all fill slopes and at fill -over-cut contacts. Keyway schematics, including dimensions and subdrain recommendations are provided in Appendix C. All keyways should be excavated into dense bedrock or dense older alluvium as determined by the geotechnical engineer.

Fills placed on slopes steeper than 5:1 (horizontal:vertical) should be benched into dense soils (see Appendix C for benching detail). Benching should be of sufficient depth to remove all loose material. A minimum bench height of 2 feet into approved material should be maintained at all times.

4.2.3 Shrinkage
The volume change of excavated onsite soils upon recompaction is expected to vary with materials, density, insitu moisture content, and location and compaction effort. The in- place and compacted densities of soil materials vary and accurate overall determination of shrinkage and bulking cannot be made. Therefore, we recommend site grading include, if possible, a balance area or ability to adjust grades slightly to accommodate some variation. Based on our review, we expect recompaction shrinkage (when recompacted to an average 93 percent of ASTM D1557) of 8- to 14-percent by volume for alluvial soils and 10 to 20 percent for any surficial topsoil/undocumented fill.
~ Leighton
a verdantas company
Geotechnical Exploration 13177.002
Town Center at Moreno Valley, Moreno Valley, California July 23, 2021 Revised January 17, 2025

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4.2.4 Import Soils
Import soils and/or borrow sites, if needed, should be evaluated by us prior to import. Import soils should be uncontaminated, granular in nature, free of organic material (loss on ignition less-than 2 percent), have low expansion potential (with an Expansion Index less than 21) and have a low corrosion impact to the proposed improvements.

4.2.5 Utility Trenches
Utility trenches should be backfilled with compacted fill in accordance with the Standard Specifications for Public Works Construction, (“Greenbook”), Current Edition. Fill material above the pipe zone should be placed in lifts not exceeding 8 inches in uncompacted thickness and should be compacted to at least 90 percent relative compaction (ASTM D 1557) by mechanical means only. Site soils may generally be suitable as trench backfill provided these soils are screened of rocks over 1½ inches in diameter and organic matter. The upper 6 inches of backfill in all pavement areas should be compacted to at least 95 percent relative compaction.

Excavation of utility trenches should be performed in accordance with the project plans, specifications and the “Greenbook”. The contractor should be responsible for providing a "competent person" as defined in Article 6 of the California Construction Safety Orders. Contractors should be advised that sandy soils (such as fills generated from the onsite alluvium) could make excavations particularly unsafe if all safety precautions are not properly implemented. In addition, excavations at or near the toe of slopes and/or parallel to slopes may be highly unstable due to the increased driving force and load on the trench wall. Spoil piles from the excavation(s) and construction equipment should be kept away from the sides of the trenches. Leighton does not consult in the area of safety engineering.

4.2.6 Drainage
All drainage should be directed away from structures a minimum of 1% by means of approved permanent/temporary drainage devices. Adequate storm drainage of any proposed pad should be provided to avoid wetting of foundation soils.

Irrigation adjacent to buildings should be avoided when possible. As an option, sealed-bottom planter boxes and/or drought resistant vegetation should be used within 5-feet of buildings.

4.2.7 Slope Construction
Compacted fill up to 25 feet in height at 2:1 (horizontal:vertical) are considered grossly stable for static and pseudostatic conditions . Higher or steeper slopes should be subject to further review and evaluation. Any new 2:1 slopes using the onsite soils compacted to minimum 90 percent should also be stable under short and long term conditions. The outer portion of new fill slopes should be either overbuilt by 2 feet (minimum) and trimmed back to the finished slope configuration ~ Leighton
a verdantas company
Geotechnical Exploration 13177.002
Town Center at Moreno Valley, Moreno Valley, California July 23, 2021 Revised January 17, 2025

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or compacted in vertical increments of 5 feet (maximum) by a weighted sheepsfoot roller as the fill is placed. The slope face should then be track-walked by dozers of appropriate weight to achieve the final slope configuration and compaction to the slope face.

New fill slopes should be provided a toe of slope keyways as depicted in Appendix C. Any new fill slopes placed along existing fill slope, the minimum new fill width should be 8 feet. If fill is placed against existing cut slope (exposing older alluvium), the minimum fill width should be 15 feet per Appendix C . All cut slopes should be observed and mapped by a Leighton geologist to confirm the exposed conditions are stable and no minor fill width is left in place. In this case, when cutting an existing fill slope back into the fill core, a minimum remaining fill width of 15 feet is recommended. Any existing cut or fill slopes to remain in the current condition should be minimally scarified to remove minor erosion rills or vermin burrow, moisture conditioned thoroughly and compacted by track walking large dozer to achieve a compacted slope face.

Slope faces are inherently subject to erosion, particularly if exposed to rainfall and irrigation. Landscaping and slope maintenance should be conducted as soon as possible in order to increase long-term surficial stability. Berms should be provided at the top of fill slopes. Drainage should be directed such that surface runoff on the slope face is minimized

4.3 Foundation Design

4.3.1 Bearing and Lateral Pressures
Based on our analysis, single -family residential structures or light commercial structures may be founded on conventional or post -tensioned slab- on-grade systems based on prevailing finish pad soils conditions after grading. The compacted fill is anticipated to possess very low expansion potential. As such, we recommend that the structural consultant and/or foundation engineer presents foundation design categories (i.e. conventional or stiffened slab-on-grade design) based on actual expansion potential of subgrade soils of each pad at completion of grading. Foundation footings may be designed with the following geotechnical design parameters:

Allowable Bearing
Capacity:
2,000 psf at a minimum depth of embedment of 12 inches (min. width of 12 inches). This bearing capacity may be increased by ⅓ for short-term loading conditions (e.g., wind, seismic).

Sliding Coefficient: 0.35
Total Settlement: 2.0 inches
Differential Settlement: 1.0 inch in 40 feet

The slab/foundation reinforcement should comply with the recommendations included in table below and the structural engineer’s requirements. ~ Leighton
a verdantas company
Geotechnical Exploration 13177.002
Town Center at Moreno Valley, Moreno Valley, California July 23, 2021 Revised January 17, 2025

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Table 3. Conventional Foundation Requirements
Conventional Foundation Minimum Requirements
Minimum Footing Reinforcement No. 4 rebar one (1) on top and one (1) on bottom.

Minimum Slab Thickness 4 inches (actual)
Minimum Slab Reinforcement No. 3 rebar spaced 18 inches on center each way.

Minimum Slab Subgrade
Moisture
110% optimum moisture to 12” depth prior to
placing concrete.

4.4 Retaining Walls
Retaining wall earth pressures are a function of the amount of wall yielding horizontally under load. If the wall can yield enough to mobilize full shear strength of backfill soils, then the wall can be designed for "active" pressure. If the wall cannot yield under th e applied load, the shear strength of the soil cannot be mobilized and the earth pressure will be higher. Such walls should be designed for "at rest" conditions. If a structure moves toward the soils, the resulting resistance developed by the soil is the "passive" resistance.

Retaining walls backfilled with non-expansive soils should be designed using the following equivalent fluid pressures:

Table 4. Retaining Wall Design Earth Pressures (Static, Drained) Loading
Conditions
Equivalent Fluid Density (pcf)
Level Backfill 2:1 Backfill
Active 36 50
At-Rest 55 85
Passive* 300 150 (2:1, sloping down)
* This assumes level condition in front of the wall will remain for the duration of the project, not to exceed 3,500 psf at depth. If sloping down (2:1) grades exist in front of walls, then they should be designed using passive values reduced to ½ of level backfill passive resistance values.

Unrestrained (yielding) cantilever walls should be designed for the active equivalent-fluid weight value provided above for very low to low expansive soils that are free draining. In the design of walls restrained from movement at the top (non-yielding) such as basement or elevator pit/utility vaults, the at-rest equivalent fluid weight value should be used. Total depth of retained earth for design of cantilever walls should be measured as the vertical distance below the ground surface measured at the wall face for stem design, or measured at the heel of the footing for overturning and sliding calculations. Should a sloping backfill other than a 2:1 (horizontal:vertical) be constructed above the wall (or a backfill is loaded by an adjacent surcharge load), the equivalent fluid weight values provided above should be re-evaluated on an individual case basis by us. Non-standard ~ Leighton
a verdantas company
Geotechnical Exploration 13177.002
Town Center at Moreno Valley, Moreno Valley, California July 23, 2021 Revised January 17, 2025

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wall designs should also be reviewed by us prior to construction to check that the proper soil parameters have been incorporated into the wall design.

All retaining walls should be provided with appropriate drainage. The outlet pipe should be sloped to drain to a suitable outlet. Typical wall drainage design is illustrated in Appendix C, Retaining Wall Backfill and Subdrain Detail . Wall backfill should be non- expansive (EI ≤ 21) sands compacted by mechanical methods to a minimum of 90 percent relative compaction (ASTM D 1557). Clayey site soils should not be used as wall backfill.

Walls should not be backfilled until wall concrete attains the 28-day compressive strength and/or as determined by the Structural Engineer that the wall is structurally capable of supporting backfill. Lightweight compaction equipment should be used, unless otherwise approved by the Structural Engineer.

4.5 Foundation Setback from Slopes
We recommend a minimum horizontal setback distance from the face of slopes for all structural footings (retaining and decorative walls, flatwork, building footings, pools, etc.).

This distance is measured from the outside bottom edge of the footing horizontally to the slope face (or the face of a retaining wall) and should be a minimum of H/2, where H is the slope height (in feet).

Table 5. Footing Setbacks
Slope Height Recommended Footing Setback
<5 feet 5 feet minimum
5 to 15 feet 7 feet minimum
>15 feet H/2, where H is the slope height, not to exceed 10 feet to 2:1 slope face

The soils within the structural setback area generally possess poor lateral stability and improvements (such as retaining walls, pools, sidewalks, fences, pavements, decorative flatwork, etc.) constructed within this setback area will be subject to lateral movement and/or differential settlement. Potential distress to such improvements may be mitigated by providing a deepened footing or a pier and grade-beam foundation system to support the improvement. The deepened footing should meet the setback described above.

Modifications of slope inclinations near foundations may increase the setback and should be reviewed by the design team prior to completion of design or implementation.

4.6 Sulfate Attack
The results of limited laboratory testing indicated negligible sulfate exposure to concrete per ACI 318. Further testing should be performed during site grading to confirm soluble- ~ Leighton
a verdantas company
Geotechnical Exploration 13177.002
Town Center at Moreno Valley, Moreno Valley, California July 23, 2021 Revised January 17, 2025

- 14 -
sulfate content of near finish subgrade soils . Additional testing for general corrosion potential to ferrous materials should also be performed during grading.

4.7 Concrete Flatwork
Sidewalk/Flatwork should conform to applicable City and County standards. A representative of Leighton should verify subgrade soil expansion, moisture conditions and compaction prior to formwork and reinforcement placement. If subgrade soils possess expansion index greater than 21, we recommend a minimum 8- inch deepened edge be constructed for all flatwork to reduce moisture variation in subgrade soils along concrete edges adjacent to open (unfinished) or irrigated landscape areas.

Concrete flatwork should be constructed of uniformly cured, low-slump concrete and should contain sufficient control/contraction joints. Additional provisions such as ascending/descending slope conditions, perched (irrigation) water, special surcharge loading conditions, potential expansive soil pressure and differential settlement/heave should be incorporated into the design of exterior improvements. Additional exterior slab details are suggested in the American Concrete Institute (ACI) guidelines. Homeowners (HOA) should be advised of their maintenance responsibilities as well as geotechnical issues that could affect performance of site improvements.

4.8 Preliminary Pavement Design
The preliminary pavement design provided below is based on the locally accepted Caltrans Highway Design Manual and a preliminary R-value of 65 based on our laboratory testing on a representative soil sample. For planning and estimating purposes, the pavement sections are calculated based on assumed Traffic Indexes (TI).

Table 6. Asphalt Pavement Sections
General Traffic
Condition*
Traffic Index
(TI)**
Asphalt
Concrete*
(inches)
Aggregate Base*
(inches)
Local (Private) Street 6.0 3.0 6.0
Collector Street 7.0 3.0 6.0
*Per City minimum or as calculated

Actual R-value of the subgrade soils will need to be verified after completion of site grading to finalize the pavement design. Pavement design and minimum sections should conform to applicable City standards, where applicable.

For rigid pavement design, we recommend that a minimum of 6 inches of PCC pavement be used, in high impact load areas or if to be subjected to truck traffic. The PCC pavement ~ Leighton
a verdantas company
Geotechnical Exploration 13177.002
Town Center at Moreno Valley, Moreno Valley, California July 23, 2021 Revised January 17, 2025

- 15 -
should be placed on a minimum 6- inch aggregate base. The PCC pavement may be placed directly on a compacted subgrade with an R -Value of 40 or higher. The PCC pavement should have a minimum of 28- day compressive strength of 3, 250 psi.

Aggregate base should conform to the Standard Specifications for Public Works Construction (Green Book), Current Edition. Placement of concrete materials should follow applicable ACI and County standards.

The upper 6 inches of the subgrade soils should be moisture-conditioned to near optimum moisture content, compacted to at least 95 percent relative compaction (ASTM D1557) and kept in this condition until the pavement section is constructed. Minimum relat ive compaction requirements for aggregate base should be 95 percent of the maximum laboratory density as determined by ASTM D1557. If applicable, aggregate base should conform to the “Standard Specifications for Public Works Construction” (Greenbook) current edition or Caltrans Class 2 aggregate base and applicable City standards

If pavement areas are adjacent to watered landscape areas, some deterioration of the subgrade load bearing capacity may result. Moisture control measures such as deepened curbs or other moisture barrier materials may be used to prevent the subgrade soils from becoming saturated. The use of concrete cutoff or edge barriers should be considered when pavement is planned adjacent to either open (unfinished) or irrigated landscaped areas.

~ Leighton
a verdantas company
Geotechnical Exploration 13177.002
Town Center at Moreno Valley, Moreno Valley, California July 23, 2021 Revised January 17, 2025

- 16 -

GEOTECHNICAL CONSTRUCTION SERVICES
Geotechnical review is of paramount importance in engineering practice. Poor performances of many foundation and earthwork projects have been attributed to inadequate construction review. We recommend that Leighton be provided the opportunity to review the grading plan and foundation plan(s) prior to bid.

Reasonably-continuous construction observation and review during site grading and foundation installation allows for evaluation of the actual soil conditions and the ability to provide appropriate revisions where required during construction. Geotechnical conclusions and preliminary recommendations should be reviewed and verified by Leighton during construction, and revised accordingly if geotechnical conditions encountered vary from our findings and interpretations. Geotechnical observation and testing should be provided:
 After completion of site clearing,
 During preparation and overexcavation of surface soils as described herein,  During compaction of all fill materials,
 Testing of slab subgrade moisture content, prior to placement of vapor retarder,  After excavation of all footings, and prior to placement of concrete,  During utility trench backfilling and compaction, and  When any unusual conditions are encountered.

Additional geotechnical exploration and analysis may be required based on final development plans, for reasons such as significant changes in proposed structure locations/footprints. We should review grading (civil) and foundation (structural) plans, and comment further on geotechnical aspects of this project.

5.0 ~ Leighton
a verdantas company
Geotechnical Exploration 13177.002
Town Center at Moreno Valley, Moreno Valley, California July 23, 2021 Revised January 17, 2025

- 17 -

LIMITATIONS
This report was necessarily based in part upon data obtained from a limited number of observances, site visits, soil samples, tests, analyses, histories of occurrences, spaced subsurface explorations and limited information on historical events and observations.

Such information is necessarily incomplete. The nature of many sites is such that differing characteristics can be experienced within small distances and under various climatic conditions. Changes in subsurface conditions can and do occur over time. This investigation was performed with the understanding that the subject site is proposed for residential and commercial development. The client is referred to Appendix D regarding important information provided by the GBA (Geoprofessional Business Association) on geotechnical engineering studies and reports and their applicability.

This report was prepared for Lewis Land Developers , LLC based on Lewis Land Developers, LLC needs, directions, and requirements at the time of our investigation.

This report is not authorized for use by, and is not to be relied upon by any party except Lewis Land Developers, LLC, and its successors and assigns as owner of the property, with whom Leighton and Associates, Inc. has contracted for the work. Use of or reliance on this report by any other party is at that party's risk. Unauthorized use of or reliance on this report constitutes an agreement to defend and indemnify Leighton and Associates, Inc. from and against any liability which may arise as a result of such use or reliance, regardless of any fault, negligence, or strict liability of Leighton and Associates, Inc.

6.0 ~ Leighton
a verdantas company
Geotechnical Exploration 13177.002
Town Center at Moreno Valley, Moreno Valley, California July 23, 2021 Revised January 17, 2025

- 18 -

REFERENCES
ASCE, 2016, ASCE Standard 7 -16, Minimum Design Loads for Buildings and Other Structures by Structural Engineering Institute
Bedrossian, T.L., and Roffers, P. D., 2012 Geologic Compilation of Quaternary Surficial Deposits in Southern California, Santa Ana 30’ X 30’ Quadrangle, CGS Special Report 217, December.

Earthquake Fault Zones, A Guide for Government Agencies, Property Oweners/Developers, and Geoscience Practitioners for Assessing Fault Rupture Hazards in California, Department of Conservation, California Geological Survey, Special Publication 42. Revised 2018.

California Building Code, (CBC) 2019, California Code of Regulations Title 24, Part 2, Volume 2 of 2.

California Department of Water Resources (CDWR) 2021, Water Data Library, http://www.water.ca.gov/waterdatalibrary/index.cfm, Data viewed July 13.

Public Works Standard, Inc., 2021, Greenbook, Standard Specifications for Public Works Construction: BNI Building News, Anaheim, California.

Riverside County Information Technology, 20 21, Map My County (website), http://mmc.rivcoit.org/MMC_Public/Viewer.html?Viewer=MMC_Public .

Applied Technology Council (ATC), Hazards by Location (website), a graphical user interface to web services provided by the United States Geological Survey, (USGS), to calculate Seismic Response and Design Parameters based on ASCE 7-16 seismic procedures, https://hazards.atcouncil.org/#/seismic United States Geological Survey, (USGS), 2021, Unified Hazard Tool (website), https://earthquake.usgs.gov/hazards/interactive/
WHA Architects, Conceptual Site Plan, Nason St. Corridor, Moreno Valley California, ~ Leighton
a verdantas company
³
0 2,000 4,000
Feet
Figure 1
Scale:

Leighton
Base Map: ESRI ArcGIS Online 2021
1 " = 2,000 '
Project: 13177.002 Eng/Geol: RIR
Map Saved as V:\Drafting\13177\002\Maps\13177-002_F01_SLM_2021-07-14.mxd on 7/15/2021 3:43:08 PM Author: Leighton Geomatics (kmanchikanti)
Date: July 2021

SITE LOCATION MAP
Lewis Moreno Valley Town Center
NW Corner of Alessandro Boulevard and Nason Street
Moreno Valley, County of Riverside, California
Approximate
Site Boundary
Map Saved as V:\Drafting\13177\002\Maps\13177-002_F02_BLM_2021-07-14.mxd on 7/20/2021 4:18:42 PM

BORING LOCATION MAP
Lewis Moreno Valley Town Center
NW Corner of Alessandro Boulevard and Nason Street
Moreno Valley, County of Riverside, California
Figure 2
³
0 300 600
Feet
Scale:

Base Map: ESRI ArcGIS Online 2021
1 " = 300 '
Project: 13177.001 Eng/Geol: RBH
Author: (kmanchikanti)
Date: July 2021
Legend
&<
Approximate Location of Soil Boring
showing Total Depth in feet below
ground surface
&& Approximate Location of Percolation
Hole
Polygon Site Features
Approximate Site Boundary
LB-18
T.D 15'
P4
Leighton
D
?zE
gr
Qvof
Qvof
Qvof
Qvof
Qyf
Qyf
Qyf
Qya Qya
Qvof
Qyf
gr
gr
gr
gr
gr
gr
gr
Qyf
Qvof
Qya
Qvof
Qvof

REGIONAL GEOLOGY MAP
Lewis Moreno Valley Town Center
NW Corner of Alessandro Boulevard and Nason Street
Moreno Valley, County of Riverside, California
Base Map: USGS Topo Map Service from Esri, 2021
Reference: Socal Preliminary Geology, CGS 2010
Project: 13177.002 Eng/Geol: RIR
Document Path: V:\Drafting\13177\002\Maps\13177-002_F03_RGM_2021-07-15.mxd Author: (kmanchikanti) Date: July 2021Scale:1 " = 2,000 '
Figure 3
Approximate
Site Limits
Geologic Units
Qyf, Young Alluvial Fan Deposits
!!
Qya, Young Alluvial Valley Deposits
Qvof, Very Old Alluvial Fan Deposits
gr, Granitic and other intrusive crystalline rocks
³
0 2,000 4,000
Feet
Leighton
,
.. . . . . . --. .. \ .. ..
. .
-

LIQUEFACTION HAZARD MAP
Lewis Moreno Valley Town Center
NW Corner of Alessandro Boulevard and Nason Street
Moreno Valley, County of Riverside, California
Base Map: USGS Topo Map Service from Esri, 2021
Reference: Riverside County GIS Leighton
Project: 13177.002 Eng/Geol: RIR
Document Path: V:\Drafting\13177\002\Maps\13177-002_F04_LHM_2021-07-15.mxd Author: (kmanchikanti) Date: July 2021Scale:1 " = 2,000 '
Figure 4
Approximate
Site Boundary
Liquefaction Susceptibility
Riverside County Liquefaction
Moderate
Low
³
0 2,000 4,000
Feet
J
0 --­.AV£
..
"1
/'
" I
Wl!I \..-
~
/
/
-v I
•.,,..,.-~ •• .
·~ . -
~
• 8 • I
,
,,,,
.--
. ...
0 - ,---• 15 -_,,,., I
I
--
Geotechnical Exploration 13177.002
Town Center at Moreno Valley, Moreno Valley, California July 23, 2021 Revised January 17, 2025

APPENDIX A

FIELD EXPLORATION / LOGS OF BORINGS

~ Leighton
a verdantas company
13 20
25 13
14 15
6 7
9 13
14 17
14 19
26 8
9 12
18 26
31 117
123
B-1
R-1
R-2
S-1
R-3
R-4
S-2
R-5
3 5
SILTY SAND, dense, pale brown to strong brown, slightly moist, Maximum Density = 134.5 pcf at Moisture = 7.9%, R-Value = 65, Fines = 24%, Sand = 70%, Gravel = 6%
SILTY SAND, medium dense, strong brown, moist
SILTY SAND, medium dense, strong brown, moist
SILTY SAND, medium dense, strong brown, moist
SILTY SAND, medium dense, strong brown, moist, Collapse =

1.14%
Well-graded SAND with silt, medium dense, yellowish brown, moist
Well-graded SAND with silt, medium dense, yellowish brown, moist
Well-graded SAND with silt, dense, yellowish brown, moist Boring Terminated at 26.5 Feet
No Groundwater Encountered
Backfilled with Soil Cuttings

MD, RV,
SA
CO
SM
SW-SM
SAMPLE TYPES:
2R Drilling
* * * This log is a part of a report by Leighton and should not be used as a stand-alone document. * * * Content, %
GEOTECHNICAL BORING LOG LB-01
Logged By
Date Drilled
DP
Feet
S
(U.S.C.S.)
Log
Type of Tests
Graphic
pcf
Location
Dry Density
N
This Soil Description applies only to a location of the exploration at the time of sampling. Subsurface conditions may differ at other locations and may change with time. The description is a simplification of the actual conditions encountered. Transitions between soil types may be gradual.

TYPE OF TESTS:
-200
AL
CN
CO
CR
CU
% FINES PASSING

ATTERBERG LIMITS

CONSOLIDATION

COLLAPSE

CORROSION

UNDRAINED TRIAXIAL
DS
EI
H
MD
PP
RV

DIRECT SHEAR

EXPANSION INDEX

HYDROMETER

MAXIMUM DENSITY

POCKET PENETROMETER

R VALUE
Hole Diameter
Moisture
Ground Elevation
Depth
Blows
Elevation
Per 6 Inches

'

BULK SAMPLE

CORE SAMPLE

GRAB SAMPLE

RING SAMPLE

SPLIT SPOON SAMPLE

TUBE SAMPLE
B
C
G
R
S
T
DP
Hollow Stem Auger - 140lb - Autohammer - 30" Drop
Soil Class.
7-1-21

SOIL DESCRIPTION
Sampled By
Drilling Co.Drilling Co.

Project
Project No.

See Boring Location Map
Lewis MV Town Center
13177.002
Drilling Method
8"
Sample No.

Feet
Attitudes
SA
SE
SG
UC

SIEVE ANALYSIS

SAND EQUIVALENT

SPECIFIC GRAVITY

UNCONFINED COMPRESSIVE STRENGTH
0 5
10 15
20 25
30 - .
-
-
-.
-·
- .
- ".
-
-
-
-
9 11
15 19
32 47
9 11
10 9
15 20
9 10
13 120
120
117
R-1
R-2
S-1
R-3
S-2
2 5
6 SILTY SAND, dense, pale brown to strong brown, slightly moist SILTY SAND, medium dense, strong brown, moist
SILTY SAND, medium dense, strong brown, moist
SILTY SAND, medium dense, light brown to yellowish brown, moist, note: cleaner than Silty Sand above
SILTY SAND, medium dense, light brown to yellowish brown, moist, FINES = 18%
SILTY SAND, dense, light brown to yellowish brown, moist -200
SM
SM
SAMPLE TYPES:
2R Drilling
* * * This log is a part of a report by Leighton and should not be used as a stand-alone document. * * * Content, %
GEOTECHNICAL BORING LOG LB-02
Logged By
Date Drilled
DP
Feet
S
(U.S.C.S.)
Log
Type of Tests
Graphic
pcf
Location
Dry Density
N
This Soil Description applies only to a location of the exploration at the time of sampling. Subsurface conditions may differ at other locations and may change with time. The description is a simplification of the actual conditions encountered. Transitions between soil types may be gradual.

TYPE OF TESTS:
-200
AL
CN
CO
CR
CU
% FINES PASSING

ATTERBERG LIMITS

CONSOLIDATION

COLLAPSE

CORROSION

UNDRAINED TRIAXIAL
DS
EI
H
MD
PP
RV

DIRECT SHEAR

EXPANSION INDEX

HYDROMETER

MAXIMUM DENSITY

POCKET PENETROMETER

R VALUE
Hole Diameter
Moisture
Ground Elevation
Depth
Blows
Elevation
Per 6 Inches

'

BULK SAMPLE

CORE SAMPLE

GRAB SAMPLE

RING SAMPLE

SPLIT SPOON SAMPLE

TUBE SAMPLE
B
C
G
R
S
T
DP
Hollow Stem Auger - 140lb - Autohammer - 30" Drop
Soil Class.
7-1-21

SOIL DESCRIPTION
Sampled By
Drilling Co.Drilling Co.

Project
Project No.

See Boring Location Map
Lewis MV Town Center
13177.002
Drilling Method
8"
Sample No.

Feet
Attitudes
SA
SE
SG
UC

SIEVE ANALYSIS

SAND EQUIVALENT

SPECIFIC GRAVITY

UNCONFINED COMPRESSIVE STRENGTH
0 5
10 15
20 25
30 - .
-
-
-.
-·
- .
-·.
-·
-
-
-.
-•
-·
-·.
-·
-
21 22
28 13
16 12
20 34
40 7
11 16
8 12
12 119R-4
S-3
R-5
S-4
S-5
3 SILTY SAND, dense, light brown to yellowish brown, moist SILTY SAND with clay, medium dense, brown, moist, FINES = 24%, with some thin interbedded clayier layers and cleaner layers
SILTY SAND, dense, light brown to yellowish brown, slightly moist, Note: less fines than above, bordering on SW-SM
SILTY SAND with clay, medium dense to dense, reddish brown, moist
SILTY SAND with clay, medium dense, reddish brown, moist Boring Terminated at 51.5 Feet
No Groundwater Encountered
Backfilled with Soil Cuttings
-200SM
SAMPLE TYPES:
2R Drilling
* * * This log is a part of a report by Leighton and should not be used as a stand-alone document. * * * Content, %
GEOTECHNICAL BORING LOG LB-02
Logged By
Date Drilled
DP
Feet
S
(U.S.C.S.)
Log
Type of Tests
Graphic
pcf
Location
Dry Density
N
This Soil Description applies only to a location of the exploration at the time of sampling. Subsurface conditions may differ at other locations and may change with time. The description is a simplification of the actual conditions encountered. Transitions between soil types may be gradual.

TYPE OF TESTS:
-200
AL
CN
CO
CR
CU
% FINES PASSING

ATTERBERG LIMITS

CONSOLIDATION

COLLAPSE

CORROSION

UNDRAINED TRIAXIAL
DS
EI
H
MD
PP
RV

DIRECT SHEAR

EXPANSION INDEX

HYDROMETER

MAXIMUM DENSITY

POCKET PENETROMETER

R VALUE
Hole Diameter
Moisture
Ground Elevation
Depth
Blows
Elevation
Per 6 Inches

'

BULK SAMPLE

CORE SAMPLE

GRAB SAMPLE

RING SAMPLE

SPLIT SPOON SAMPLE

TUBE SAMPLE
B
C
G
R
S
T
DP
Hollow Stem Auger - 140lb - Autohammer - 30" Drop
Soil Class.
7-1-21

SOIL DESCRIPTION
Sampled By
Drilling Co.Drilling Co.

Project
Project No.

See Boring Location Map
Lewis MV Town Center
13177.002
Drilling Method
8"
Sample No.

Feet
Attitudes
SA
SE
SG
UC

SIEVE ANALYSIS

SAND EQUIVALENT

SPECIFIC GRAVITY

UNCONFINED COMPRESSIVE STRENGTH
30 35
40 45
50 55
60 - .
- .
- ·
-
-
-•
-·
- .
- ·
- ·
-
-
-.
-
-
-
-
5 7
10 8
9 10
5 6
10 10
15 26
8 12
14 10
14 27
110
114
122
R-1
R-2
R-3
R-4
R-5
R-6
4 2
6 SILTY SAND, loose, pale brown to strong brown, slightly moist, Maximum Density = 133.6 pcf at Moisture = 7.5%, Fines = 27%, Sand = 69%, Gravel = 4%
SILTY SAND, medium dense, strong brown, moist
SILTY SAND, medium dense, strong brown, moist, Collapse =

2.79%
Well-graded SAND with silt and gravel, medium dense, light brown to yellowish brown, moist
SILTY SAND, medium dense, brown to strong brown, moist
SILTY SAND, medium dense, brown to strong brown, moist
Well-graded SAND with silt and gravel, medium dense, light brown to yellowish brown, moist
Boring Terminated at 21.5 Feet
No Groundwater Encountered
Backfilled with Soil Cuttings
MD, SA
CO
SM
SW-SM
SM
SW-SM
SAMPLE TYPES:
2R Drilling
* * * This log is a part of a report by Leighton and should not be used as a stand-alone document. * * * Content, %
GEOTECHNICAL BORING LOG LB-03
Logged By
Date Drilled
DP
Feet
S
(U.S.C.S.)
Log
Type of Tests
Graphic
pcf
Location
Dry Density
N
This Soil Description applies only to a location of the exploration at the time of sampling. Subsurface conditions may differ at other locations and may change with time. The description is a simplification of the actual conditions encountered. Transitions between soil types may be gradual.

TYPE OF TESTS:
-200
AL
CN
CO
CR
CU
% FINES PASSING

ATTERBERG LIMITS

CONSOLIDATION

COLLAPSE

CORROSION

UNDRAINED TRIAXIAL
DS
EI
H
MD
PP
RV

DIRECT SHEAR

EXPANSION INDEX

HYDROMETER

MAXIMUM DENSITY

POCKET PENETROMETER

R VALUE
Hole Diameter
Moisture
Ground Elevation
Depth
Blows
Elevation
Per 6 Inches

'

BULK SAMPLE

CORE SAMPLE

GRAB SAMPLE

RING SAMPLE

SPLIT SPOON SAMPLE

TUBE SAMPLE
B
C
G
R
S
T
DP
Hollow Stem Auger - 140lb - Autohammer - 30" Drop
Soil Class.
7-1-21

SOIL DESCRIPTION
Sampled By
Drilling Co.Drilling Co.

Project
Project No.

See Boring Location Map
Lewis MV Town Center
13177.002
Drilling Method
8"
Sample No.

Feet
Attitudes
SA
SE
SG
UC

SIEVE ANALYSIS

SAND EQUIVALENT

SPECIFIC GRAVITY

UNCONFINED COMPRESSIVE STRENGTH
0 5
10 15
20 25
30 -
-
-
-
,,
,, -
,,
,,
- ,,
-
-
-
-
,,
- ,,
,,
- ,,
-
-
-
-
10 17
24 15
33 30
16 22
29 20
18 30
5 8
7 19
18 27
120
117
R-1
S-1
R-2
R-3
S-2
R-4
2 2
SILTY SAND with gravel, loose, pale brown to strong brown, slightly moist
SILTY SAND with gravel, medium dense, strong brown, moist SILTY SAND with gravel, medium dense, strong brown, moist SILTY SAND with gravel, medium dense, strong brown, moist Well-graded SAND with silt, medium dense, brown to yellowish brown, moist
Well-graded SAND with silt, medium dense, yellowish brown, slightly moist
SILTY SAND, medium dense, brown to strong brown, moist, fine sand
Boring Terminated at 21.5 Feet
No Groundwater Encountered
Backfilled with Soil Cuttings
SM
SW-SM
SM
SAMPLE TYPES:
2R Drilling
* * * This log is a part of a report by Leighton and should not be used as a stand-alone document. * * * Content, %
GEOTECHNICAL BORING LOG LB-04
Logged By
Date Drilled
DP
Feet
S
(U.S.C.S.)
Log
Type of Tests
Graphic
pcf
Location
Dry Density
N
This Soil Description applies only to a location of the exploration at the time of sampling. Subsurface conditions may differ at other locations and may change with time. The description is a simplification of the actual conditions encountered. Transitions between soil types may be gradual.

TYPE OF TESTS:
-200
AL
CN
CO
CR
CU
% FINES PASSING

ATTERBERG LIMITS

CONSOLIDATION

COLLAPSE

CORROSION

UNDRAINED TRIAXIAL
DS
EI
H
MD
PP
RV

DIRECT SHEAR

EXPANSION INDEX

HYDROMETER

MAXIMUM DENSITY

POCKET PENETROMETER

R VALUE
Hole Diameter
Moisture
Ground Elevation
Depth
Blows
Elevation
Per 6 Inches

'

BULK SAMPLE

CORE SAMPLE

GRAB SAMPLE

RING SAMPLE

SPLIT SPOON SAMPLE

TUBE SAMPLE
B
C
G
R
S
T
DP
Hollow Stem Auger - 140lb - Autohammer - 30" Drop
Soil Class.
7-1-21

SOIL DESCRIPTION
Sampled By
Drilling Co.Drilling Co.

Project
Project No.

See Boring Location Map
Lewis MV Town Center
13177.002
Drilling Method
8"
Sample No.

Feet
Attitudes
SA
SE
SG
UC

SIEVE ANALYSIS

SAND EQUIVALENT

SPECIFIC GRAVITY

UNCONFINED COMPRESSIVE STRENGTH
0 5
10 15
20 25
30 I I I I I I I I I I I I I I I I I I I I I I I I I I I b " b" b' b' b ' b ' b ' b ' b ' b "
,__ _________________ _,
t
5 9
12 24
50/6"
10 8
8 16
16 20
7 12
18 117
118
R-1
B-1
R-2
S-1
R-3
R-4
3 4
SILTY SAND with gravel, loose, pale brown to strong brown, slightly moist
SILTY SAND with gravel, medium dense, strong brown, moist SILTY SAND with gravel, medium dense, strong brown, moist, EI = 1 (Very Low)
SILTY SAND with gravel, medium dense, strong brown, moist Well-graded SAND with silt, medium dense, brown to yellowish brown, moist, with interbedded poorly-graded sand layers Well-graded SAND with silt, medium dense, yellowish brown, slightly moist
Boring Terminated at 16.5 Feet
No Groundwater Encountered
Backfilled with Soil Cuttings
EI
SM
SW-SM
SAMPLE TYPES:
2R Drilling
* * * This log is a part of a report by Leighton and should not be used as a stand-alone document. * * * Content, %
GEOTECHNICAL BORING LOG LB-05
Logged By
Date Drilled
DP
Feet
S
(U.S.C.S.)
Log
Type of Tests
Graphic
pcf
Location
Dry Density
N
This Soil Description applies only to a location of the exploration at the time of sampling. Subsurface conditions may differ at other locations and may change with time. The description is a simplification of the actual conditions encountered. Transitions between soil types may be gradual.

TYPE OF TESTS:
-200
AL
CN
CO
CR
CU
% FINES PASSING

ATTERBERG LIMITS

CONSOLIDATION

COLLAPSE

CORROSION

UNDRAINED TRIAXIAL
DS
EI
H
MD
PP
RV

DIRECT SHEAR

EXPANSION INDEX

HYDROMETER

MAXIMUM DENSITY

POCKET PENETROMETER

R VALUE
Hole Diameter
Moisture
Ground Elevation
Depth
Blows
Elevation
Per 6 Inches

'

BULK SAMPLE

CORE SAMPLE

GRAB SAMPLE

RING SAMPLE

SPLIT SPOON SAMPLE

TUBE SAMPLE
B
C
G
R
S
T
DP
Hollow Stem Auger - 140lb - Autohammer - 30" Drop
Soil Class.
7-1-21

SOIL DESCRIPTION
Sampled By
Drilling Co.Drilling Co.

Project
Project No.

See Boring Location Map
Lewis MV Town Center
13177.002
Drilling Method
8"
Sample No.

Feet
Attitudes
SA
SE
SG
UC

SIEVE ANALYSIS

SAND EQUIVALENT

SPECIFIC GRAVITY

UNCONFINED COMPRESSIVE STRENGTH
0 5
10 15
20 25
30 I I I I I I I I I I I I I I I I I I I I I I I I I I I I ~ . ~ . ~ . ~ . ~ . ~ . >--------------------------1
t
5 8
10 7
6 8
7 10
10 3
5 6
18 26
32 5
8 13
12 37
50/6"
114
108
117
R-1
R-2
R-3
S-1
R-4
S-2
R-5
3 2
2 SILTY SAND with gravel, dense, pale brown to strong brown, slightly moist
SILTY SAND with gravel, medium dense, strong brown, moist SILTY SAND with gravel, medium dense, strong brown, moist, Collapse = 3.67%
Well-graded SAND with silt, medium dense, yellowish brown to light brown, moist
SILTY SAND, loose, brown, moist
SILTY SAND, dense, brown, moist
Well-graded SAND with silt, medium dense, brown, moist, with interbeds of Silty Sand
Well-graded SAND with silt, dense, brown, moist
Boring Terminated at 26.5 Feet
No Groundwater Encountered
Backfilled with Soil Cuttings
CO
SM
SW-SM
SM
SW-SM
SAMPLE TYPES:
2R Drilling
* * * This log is a part of a report by Leighton and should not be used as a stand-alone document. * * * Content, %
GEOTECHNICAL BORING LOG LB-06
Logged By
Date Drilled
DP
Feet
S
(U.S.C.S.)
Log
Type of Tests
Graphic
pcf
Location
Dry Density
N
This Soil Description applies only to a location of the exploration at the time of sampling. Subsurface conditions may differ at other locations and may change with time. The description is a simplification of the actual conditions encountered. Transitions between soil types may be gradual.

TYPE OF TESTS:
-200
AL
CN
CO
CR
CU
% FINES PASSING

ATTERBERG LIMITS

CONSOLIDATION

COLLAPSE

CORROSION

UNDRAINED TRIAXIAL
DS
EI
H
MD
PP
RV

DIRECT SHEAR

EXPANSION INDEX

HYDROMETER

MAXIMUM DENSITY

POCKET PENETROMETER

R VALUE
Hole Diameter
Moisture
Ground Elevation
Depth
Blows
Elevation
Per 6 Inches

'

BULK SAMPLE

CORE SAMPLE

GRAB SAMPLE

RING SAMPLE

SPLIT SPOON SAMPLE

TUBE SAMPLE
B
C
G
R
S
T
DP
Hollow Stem Auger - 140lb - Autohammer - 30" Drop
Soil Class.
7-1-21

SOIL DESCRIPTION
Sampled By
Drilling Co.Drilling Co.

Project
Project No.

See Boring Location Map
Lewis MV Town Center
13177.002
Drilling Method
8"
Sample No.

Feet
Attitudes
SA
SE
SG
UC

SIEVE ANALYSIS

SAND EQUIVALENT

SPECIFIC GRAVITY

UNCONFINED COMPRESSIVE STRENGTH
0 5
10 15
20 25
30 - .
-
-
-
-
- .
-
-
4 4
- 4
4 - 4
4 4
-
4 -
-
6 5
12 9
12 14
5 7
8 10
11 13
15 19
18 9
15 21
116
118
112
R-1
R-2
S-1
R-3
S-2
R-4
3 3
5 SILTY SAND with gravel, loose, pale brown to strong brown, slightly moist
SILTY SAND with gravel, medium dense, strong brown, moist SILTY SAND with gravel, medium dense, strong brown, moist SILTY SAND, medium dense, strong brown, moist
SILTY SAND, medium dense, strong brown, moist, Collapse =

4.73%
SANDY SILT or SILTY SAND, dense, dark reddish brown, moist Well-graded SAND with silt and clay, medium dense, brown, moist
Boring Terminated at 21.5 Feet
No Groundwater Encountered
Backfilled with Soil Cuttings
CO
SM
ML
SW-SM
SAMPLE TYPES:
2R Drilling
* * * This log is a part of a report by Leighton and should not be used as a stand-alone document. * * * Content, %
GEOTECHNICAL BORING LOG LB-07
Logged By
Date Drilled
DP
Feet
S
(U.S.C.S.)
Log
Type of Tests
Graphic
pcf
Location
Dry Density
N
This Soil Description applies only to a location of the exploration at the time of sampling. Subsurface conditions may differ at other locations and may change with time. The description is a simplification of the actual conditions encountered. Transitions between soil types may be gradual.

TYPE OF TESTS:
-200
AL
CN
CO
CR
CU
% FINES PASSING

ATTERBERG LIMITS

CONSOLIDATION

COLLAPSE

CORROSION

UNDRAINED TRIAXIAL
DS
EI
H
MD
PP
RV

DIRECT SHEAR

EXPANSION INDEX

HYDROMETER

MAXIMUM DENSITY

POCKET PENETROMETER

R VALUE
Hole Diameter
Moisture
Ground Elevation
Depth
Blows
Elevation
Per 6 Inches

'

BULK SAMPLE

CORE SAMPLE

GRAB SAMPLE

RING SAMPLE

SPLIT SPOON SAMPLE

TUBE SAMPLE
B
C
G
R
S
T
DP
Hollow Stem Auger - 140lb - Autohammer - 30" Drop
Soil Class.
7-1-21

SOIL DESCRIPTION
Sampled By
Drilling Co.Drilling Co.

Project
Project No.

See Boring Location Map
Lewis MV Town Center
13177.002
Drilling Method
8"
Sample No.

Feet
Attitudes
SA
SE
SG
UC

SIEVE ANALYSIS

SAND EQUIVALENT

SPECIFIC GRAVITY

UNCONFINED COMPRESSIVE STRENGTH
0 5
10 15
20 25
30 - .
-
-
-.
-·
-
-
-
~
-
~
~
- ~
-
-
-
-
4 5
7 3
5 7
4 5
9 5
6 9
16 26
36 105
112
113
113
B-1
R-1
R-2
R-3
R-4
R-5
6 5
5 5
SILTY SAND with gravel, loose, pale brown to strong brown, slightly moist
SILTY SAND with gravel, loose, strong brown, moist
SILTY SAND with gravel, loose, strong brown, moist, Collapse =

5.60%
SILTY SAND with gravel, loose, strong brown, moist
SILTY SAND, loose, strong brown, moist, Collapse = 4.77% SANDY SILT or SILTY SAND, dense, dark reddish brown,
slightly moist
Boring Terminated at 16.5 Feet
No Groundwater Encountered
Backfilled with Soil Cuttings
CO
CO
SM
ML
SAMPLE TYPES:
2R Drilling
* * * This log is a part of a report by Leighton and should not be used as a stand-alone document. * * * Content, %
GEOTECHNICAL BORING LOG LB-08
Logged By
Date Drilled
DP
Feet
S
(U.S.C.S.)
Log
Type of Tests
Graphic
pcf
Location
Dry Density
N
This Soil Description applies only to a location of the exploration at the time of sampling. Subsurface conditions may differ at other locations and may change with time. The description is a simplification of the actual conditions encountered. Transitions between soil types may be gradual.

TYPE OF TESTS:
-200
AL
CN
CO
CR
CU
% FINES PASSING

ATTERBERG LIMITS

CONSOLIDATION

COLLAPSE

CORROSION

UNDRAINED TRIAXIAL
DS
EI
H
MD
PP
RV

DIRECT SHEAR

EXPANSION INDEX

HYDROMETER

MAXIMUM DENSITY

POCKET PENETROMETER

R VALUE
Hole Diameter
Moisture
Ground Elevation
Depth
Blows
Elevation
Per 6 Inches

'

BULK SAMPLE

CORE SAMPLE

GRAB SAMPLE

RING SAMPLE

SPLIT SPOON SAMPLE

TUBE SAMPLE
B
C
G
R
S
T
DP
Hollow Stem Auger - 140lb - Autohammer - 30" Drop
Soil Class.
7-1-21

SOIL DESCRIPTION
Sampled By
Drilling Co.Drilling Co.

Project
Project No.

See Boring Location Map
Lewis MV Town Center
13177.002
Drilling Method
8"
Sample No.

Feet
Attitudes
SA
SE
SG
UC

SIEVE ANALYSIS

SAND EQUIVALENT

SPECIFIC GRAVITY

UNCONFINED COMPRESSIVE STRENGTH
0 5
10 15
20 25
30 - .
-
-
-.
-·
- .
-
-
-
-
-
-
-
-
-
Silty SAND with Gravel, medium dense, brown, slightly moist Boring Terminated at 7 Feet
No Groundwater Encountered
Backfilled with Soil Cuttings After Percolation Test
SM
SAMPLE TYPES:
2R Drilling
* * * This log is a part of a report by Leighton and should not be used as a stand-alone document. * * * Content, %
GEOTECHNICAL BORING LOG P-01
Logged By
Date Drilled
DP
Feet
S
(U.S.C.S.)
Log
Type of Tests
Graphic
pcf
Location
Dry Density
N
This Soil Description applies only to a location of the exploration at the time of sampling. Subsurface conditions may differ at other locations and may change with time. The description is a simplification of the actual conditions encountered. Transitions between soil types may be gradual.

TYPE OF TESTS:
-200
AL
CN
CO
CR
CU
% FINES PASSING

ATTERBERG LIMITS

CONSOLIDATION

COLLAPSE

CORROSION

UNDRAINED TRIAXIAL
DS
EI
H
MD
PP
RV

DIRECT SHEAR

EXPANSION INDEX

HYDROMETER

MAXIMUM DENSITY

POCKET PENETROMETER

R VALUE
Hole Diameter
Moisture
Ground Elevation
Depth
Blows
Elevation
Per 6 Inches

'

BULK SAMPLE

CORE SAMPLE

GRAB SAMPLE

RING SAMPLE

SPLIT SPOON SAMPLE

TUBE SAMPLE
B
C
G
R
S
T
DP
Hollow Stem Auger - 140lb - Autohammer - 30" Drop
Soil Class.
7-1-21

SOIL DESCRIPTION
Sampled By
Drilling Co.Drilling Co.

Project
Project No.

See Boring Location Map
Lewis MV Town Center
13177.002
Drilling Method
8"
Sample No.

Feet
Attitudes
SA
SE
SG
UC

SIEVE ANALYSIS

SAND EQUIVALENT

SPECIFIC GRAVITY

UNCONFINED COMPRESSIVE STRENGTH
0 5
10 15
20 25
30 - .
-
-
-
-
-
-
-
-
-
-
-
-
-
-
Silty SAND with Gravel, medium dense, brown, slightly moist Boring Terminated at 5 Feet
No Groundwater Encountered
Backfilled with Soil Cuttings After Percolation Test
SM
SAMPLE TYPES:
2R Drilling
* * * This log is a part of a report by Leighton and should not be used as a stand-alone document. * * * Content, %
GEOTECHNICAL BORING LOG P-02
Logged By
Date Drilled
DP
Feet
S
(U.S.C.S.)
Log
Type of Tests
Graphic
pcf
Location
Dry Density
N
This Soil Description applies only to a location of the exploration at the time of sampling. Subsurface conditions may differ at other locations and may change with time. The description is a simplification of the actual conditions encountered. Transitions between soil types may be gradual.

TYPE OF TESTS:
-200
AL
CN
CO
CR
CU
% FINES PASSING

ATTERBERG LIMITS

CONSOLIDATION

COLLAPSE

CORROSION

UNDRAINED TRIAXIAL
DS
EI
H
MD
PP
RV

DIRECT SHEAR

EXPANSION INDEX

HYDROMETER

MAXIMUM DENSITY

POCKET PENETROMETER

R VALUE
Hole Diameter
Moisture
Ground Elevation
Depth
Blows
Elevation
Per 6 Inches

'

BULK SAMPLE

CORE SAMPLE

GRAB SAMPLE

RING SAMPLE

SPLIT SPOON SAMPLE

TUBE SAMPLE
B
C
G
R
S
T
DP
Hollow Stem Auger - 140lb - Autohammer - 30" Drop
Soil Class.
7-1-21

SOIL DESCRIPTION
Sampled By
Drilling Co.Drilling Co.

Project
Project No.

See Boring Location Map
Lewis MV Town Center
13177.002
Drilling Method
8"
Sample No.

Feet
Attitudes
SA
SE
SG
UC

SIEVE ANALYSIS

SAND EQUIVALENT

SPECIFIC GRAVITY

UNCONFINED COMPRESSIVE STRENGTH
0 5
10 15
20 25
30 - .
-
-
-
-
-
-
-
-
-
-
-
-
-
-
Silty SAND, loose, pale brown, slightly moist, fine sand Boring Terminated at 5 Feet
No Groundwater Encountered
Backfilled with Soil Cuttings After Percolation Test
SM
SAMPLE TYPES:
2R Drilling
* * * This log is a part of a report by Leighton and should not be used as a stand-alone document. * * * Content, %
GEOTECHNICAL BORING LOG P-03
Logged By
Date Drilled
DP
Feet
S
(U.S.C.S.)
Log
Type of Tests
Graphic
pcf
Location
Dry Density
N
This Soil Description applies only to a location of the exploration at the time of sampling. Subsurface conditions may differ at other locations and may change with time. The description is a simplification of the actual conditions encountered. Transitions between soil types may be gradual.

TYPE OF TESTS:
-200
AL
CN
CO
CR
CU
% FINES PASSING

ATTERBERG LIMITS

CONSOLIDATION

COLLAPSE

CORROSION

UNDRAINED TRIAXIAL
DS
EI
H
MD
PP
RV

DIRECT SHEAR

EXPANSION INDEX

HYDROMETER

MAXIMUM DENSITY

POCKET PENETROMETER

R VALUE
Hole Diameter
Moisture
Ground Elevation
Depth
Blows
Elevation
Per 6 Inches

'

BULK SAMPLE

CORE SAMPLE

GRAB SAMPLE

RING SAMPLE

SPLIT SPOON SAMPLE

TUBE SAMPLE
B
C
G
R
S
T
DP
Hollow Stem Auger - 140lb - Autohammer - 30" Drop
Soil Class.
7-1-21

SOIL DESCRIPTION
Sampled By
Drilling Co.Drilling Co.

Project
Project No.

See Boring Location Map
Lewis MV Town Center
13177.002
Drilling Method
8"
Sample No.

Feet
Attitudes
SA
SE
SG
UC

SIEVE ANALYSIS

SAND EQUIVALENT

SPECIFIC GRAVITY

UNCONFINED COMPRESSIVE STRENGTH
0 5
10 15
20 25
30 - .
-
-
-
-
-
-
-
-
-
-
-
-
-
-
6 10
13 R1
Silty SAND, loose, pale brown, slightly moist, fine sand, FINES = 42%
Boring Terminated at 5 Feet
No Groundwater Encountered
Backfilled with Soil Cuttings After Percolation Test
-200
SM
SAMPLE TYPES:
2R Drilling
* * * This log is a part of a report by Leighton and should not be used as a stand-alone document. * * * Content, %
GEOTECHNICAL BORING LOG P-04
Logged By
Date Drilled
DP
Feet
S
(U.S.C.S.)
Log
Type of Tests
Graphic
pcf
Location
Dry Density
N
This Soil Description applies only to a location of the exploration at the time of sampling. Subsurface conditions may differ at other locations and may change with time. The description is a simplification of the actual conditions encountered. Transitions between soil types may be gradual.

TYPE OF TESTS:
-200
AL
CN
CO
CR
CU
% FINES PASSING

ATTERBERG LIMITS

CONSOLIDATION

COLLAPSE

CORROSION

UNDRAINED TRIAXIAL
DS
EI
H
MD
PP
RV

DIRECT SHEAR

EXPANSION INDEX

HYDROMETER

MAXIMUM DENSITY

POCKET PENETROMETER

R VALUE
Hole Diameter
Moisture
Ground Elevation
Depth
Blows
Elevation
Per 6 Inches

'

BULK SAMPLE

CORE SAMPLE

GRAB SAMPLE

RING SAMPLE

SPLIT SPOON SAMPLE

TUBE SAMPLE
B
C
G
R
S
T
DP
Hollow Stem Auger - 140lb - Autohammer - 30" Drop
Soil Class.
7-1-21

SOIL DESCRIPTION
Sampled By
Drilling Co.Drilling Co.

Project
Project No.

See Boring Location Map
Lewis MV Town Center
13177.002
Drilling Method
8"
Sample No.

Feet
Attitudes
SA
SE
SG
UC

SIEVE ANALYSIS

SAND EQUIVALENT

SPECIFIC GRAVITY

UNCONFINED COMPRESSIVE STRENGTH
0 5
10 15
20 25
30 - .
-
-
-
-
-
-
-
-
-
-
-
-
-
-
Geotechnical Exploration 13177.002
Town Center at Moreno Valley, Moreno Valley, California July 23, 2021 Revised January 17, 2025

APPENDIX B

GEOTECHNICAL LABORATORY TEST RESULTS

~ Leighton
a verdantas company

Project Name: Tested By: M. Vinet Date: 7/15/21
Project No.: Checked By: M. Vinet Date: 7/16/21
Boring No.: LB-1 Sample Type: IN SITU
Sample No.: R-3 Depth (ft.) 10.0
Sample Description:

Source and Type of Water Used for Inundation: Arrowhead ( Distilled ) ** Note: Loading After Wetting (Inundation) not Performed Using this Test Method.

Initial Dry Density (pcf): 115.4 Final Dry Density (pcf): 117.6 Initial Moisture (%): 7.4 Final Moisture (%) : 12.8
Initial Height (in.): 1.0000 Initial Void ratio: 0.4604 Initial Dial Reading (in): 0.0000 Specific Gravity (assumed): 2.70 Inside Diameter of Ring (in): 2.416 Initial Degree of Saturation (%): 43.5

1.050 0.9963 0.00 -0.37 -0.37

2.013 0.9927 0.00 -0.73 -0.73
H2O 0.9814 0.00 -1.86 -1.86
-1.14

Rev. 01-10
Lewis/MV Town Center/Geo

0.4333

0.0037

0.0073

0.0186
Silty Sand (SM), Brown.
13177.002
Swell (+)
Settlement (-)
% of Sample
Thickness
Load
Compliance
(%)
Apparent
Thickness
(in)
(ASTM D 4546) -- Method 'B'
Potential of Cohesive Soils
One-Dimensional Swell or Settlement
Percent Swell / Settlement After Inundation =
Corrected
Deformation
(%)
Pressure (p)
(ksf)

0.4550

0.4498
Final Reading
(in) Void Ratio
-5.00
-4.00
-3.00
-2.00
-1.00

0.00 1.00

2.00 3.00

4.00 5.00

0.010 0.100 1.000 10.000
Deformation %
Log Pressure (ksf)
Deformation % - Log Pressure Curve
Inundate With
Distilled Water
Leighton
I
..
'1
~ · r
I

Project Name: Tested By: M. Vinet Date: 7/15/21
Project No.: Checked By: M. Vinet Date: 7/16/21
Boring No.: LB-3 Sample Type: IN SITU
Sample No.: R-2 Depth (ft.) 5.0
Sample Description:

Source and Type of Water Used for Inundation: Arrowhead ( Distilled ) ** Note: Loading After Wetting (Inundation) not Performed Using this Test Method.

Initial Dry Density (pcf): 109.8 Final Dry Density (pcf): 114.6 Initial Moisture (%): 3.1 Final Moisture (%) : 15.8
Initial Height (in.): 1.0000 Initial Void ratio: 0.5355 Initial Dial Reading (in): 0.0000 Specific Gravity (assumed): 2.70 Inside Diameter of Ring (in): 2.416 Initial Degree of Saturation (%): 15.6

1.050 0.9928 0.00 -0.72 -0.72

2.013 0.9855 0.00 -1.45 -1.45
H2O 0.9580 0.00 -4.20 -4.20
-2.79

Rev. 01-10
Lewis/MV Town Center/Geo

0.4710

0.0072

0.0145

0.0420
Silty Sand (SM), Yellowish Brown.
13177.002
Swell (+)
Settlement (-)
% of Sample
Thickness
Load
Compliance
(%)
Apparent
Thickness
(in)
(ASTM D 4546) -- Method 'B'
Potential of Cohesive Soils
One-Dimensional Swell or Settlement
Percent Swell / Settlement After Inundation =
Corrected
Deformation
(%)
Pressure (p)
(ksf)

0.5245

0.5132
Final Reading
(in) Void Ratio
-5.00
-4.00
-3.00
-2.00
-1.00

0.00 1.00

2.00 3.00

4.00 5.00

0.010 0.100 1.000 10.000
Deformation %
Log Pressure (ksf)
Deformation % - Log Pressure Curve
Inundate With
Distilled Water
Leighton
I
L..
.........

I
I
j ..

Project Name: Tested By: M. Vinet Date: 7/15/21
Project No.: Checked By: M. Vinet Date: 7/16/21
Boring No.: LB-6 Sample Type: IN SITU
Sample No.: R-2 Depth (ft.) 5.0
Sample Description:

Source and Type of Water Used for Inundation: Arrowhead ( Distilled ) ** Note: Loading After Wetting (Inundation) not Performed Using this Test Method.

Initial Dry Density (pcf): 100.6 Final Dry Density (pcf): 105.5 Initial Moisture (%): 4.4 Final Moisture (%) : 18.2
Initial Height (in.): 1.0000 Initial Void ratio: 0.6750 Initial Dial Reading (in): 0.0000 Specific Gravity (assumed): 2.70 Inside Diameter of Ring (in): 2.416 Initial Degree of Saturation (%): 17.5

1.050 0.9950 0.00 -0.50 -0.50

2.013 0.9906 0.00 -0.94 -0.94
H2O 0.9542 0.00 -4.58 -4.58
-3.67

Rev. 01-10
Lewis/MV Town Center/Geo

0.5983

0.0050

0.0094

0.0458
Silty Sand (SM), Yellowish Brown.
13177.002
Swell (+)
Settlement (-)
% of Sample
Thickness
Load
Compliance
(%)
Apparent
Thickness
(in)
(ASTM D 4546) -- Method 'B'
Potential of Cohesive Soils
One-Dimensional Swell or Settlement
Percent Swell / Settlement After Inundation =
Corrected
Deformation
(%)
Pressure (p)
(ksf)

0.6666

0.6592
Final Reading
(in) Void Ratio
-5.00
-4.00
-3.00
-2.00
-1.00

0.00 1.00

2.00 3.00

4.00 5.00

0.010 0.100 1.000 10.000
Deformation %
Log Pressure (ksf)
Deformation % - Log Pressure Curve
Inundate With
Distilled Water
Leighton
I
.. ----..........

I -
I
' l

Project Name: Tested By: M. Vinet Date: 7/15/21
Project No.: Checked By: M. Vinet Date: 7/16/21
Boring No.: LB-7 Sample Type: IN SITU
Sample No.: R-3 Depth (ft.) 10
Sample Description:

Source and Type of Water Used for Inundation: Arrowhead ( Distilled ) ** Note: Loading After Wetting (Inundation) not Performed Using this Test Method.

Initial Dry Density (pcf): 104.1 Final Dry Density (pcf): 111.2 Initial Moisture (%): 4.0 Final Moisture (%) : 16.5
Initial Height (in.): 1.0000 Initial Void ratio: 0.6196 Initial Dial Reading (in): 0.0000 Specific Gravity (assumed): 2.70 Inside Diameter of Ring (in): 2.416 Initial Degree of Saturation (%): 17.6

1.050 0.9927 0.00 -0.73 -0.73

2.013 0.9827 0.00 -1.73 -1.73
H2O 0.9362 0.00 -6.38 -6.38
-4.73

Rev. 01-10
Lewis/MV Town Center/Geo

0.5163

0.0073

0.0173

0.0638
Silty Sand (SM), Brown.
13177.002
Swell (+)
Settlement (-)
% of Sample
Thickness
Load
Compliance
(%)
Apparent
Thickness
(in)
(ASTM D 4546) -- Method 'B'
Potential of Cohesive Soils
One-Dimensional Swell or Settlement
Percent Swell / Settlement After Inundation =
Corrected
Deformation
(%)
Pressure (p)
(ksf)

0.6078

0.5916
Final Reading
(in) Void Ratio
-8.00
-7.00
-6.00
-5.00
-4.00
-3.00
-2.00
-1.00

0.00 1.00

2.00 3.00

0.010 0.100 1.000 10.000
Deformation %
Log Pressure (ksf)
Deformation % - Log Pressure Curve
Inundate With
Distilled Water
Leighton
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Project Name: Tested By: M. Vinet Date: 7/15/21
Project No.: Checked By: M. Vinet Date: 7/16/21
Boring No.: LB-8 Sample Type: IN SITU
Sample No.: R-2 Depth (ft.) 5.0
Sample Description:

Source and Type of Water Used for Inundation: Arrowhead ( Distilled ) ** Note: Loading After Wetting (Inundation) not Performed Using this Test Method.

Initial Dry Density (pcf): 100.7 Final Dry Density (pcf): 110.9 Initial Moisture (%): 6.4 Final Moisture (%) : 17.4
Initial Height (in.): 1.0000 Initial Void ratio: 0.6737 Initial Dial Reading (in): 0.0000 Specific Gravity (assumed): 2.70 Inside Diameter of Ring (in): 2.416 Initial Degree of Saturation (%): 25.8

1.050 0.9774 0.00 -2.26 -2.26

2.013 0.9615 0.00 -3.85 -3.85
H2O 0.9077 0.00 -9.23 -9.23
-5.60

Rev. 01-10
Lewis/MV Town Center/Geo

0.5193

0.0226

0.0385

0.0923
Silty Sand (SM), Brown.
13177.002
Swell (+)
Settlement (-)
% of Sample
Thickness
Load
Compliance
(%)
Apparent
Thickness
(in)
(ASTM D 4546) -- Method 'B'
Potential of Cohesive Soils
One-Dimensional Swell or Settlement
Percent Swell / Settlement After Inundation =
Corrected
Deformation
(%)
Pressure (p)
(ksf)

0.6359

0.6093
Final Reading
(in) Void Ratio
-10.00
-9.00
-8.00
-7.00
-6.00
-5.00
-4.00
-3.00
-2.00
-1.00

0.00 0.010 0.100 1.000 10.000
Deformation %
Log Pressure (ksf)
Deformation % - Log Pressure Curve
Inundate With
Distilled Water
Leighton
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Project Name: Tested By: M. Vinet Date: 7/15/21
Project No.: Checked By: M. Vinet Date: 7/16/21
Boring No.: LB-8 Sample Type: IN SITU
Sample No.: R-4 Depth (ft.) 10.0
Sample Description:

Source and Type of Water Used for Inundation: Arrowhead ( Distilled ) ** Note: Loading After Wetting (Inundation) not Performed Using this Test Method.

Initial Dry Density (pcf): 102.9 Final Dry Density (pcf): 111.5 Initial Moisture (%): 6.2 Final Moisture (%) : 18.0
Initial Height (in.): 1.0000 Initial Void ratio: 0.6385 Initial Dial Reading (in): 0.0000 Specific Gravity (assumed): 2.70 Inside Diameter of Ring (in): 2.416 Initial Degree of Saturation (%): 26.3

1.050 0.9827 0.00 -1.73 -1.73

2.013 0.9692 0.00 -3.08 -3.08
H2O 0.9230 0.00 -7.70 -7.70
-4.77

Rev. 01-10
Lewis/MV Town Center/Geo

0.5123

0.0173

0.0308

0.0770
Silty Sand (SM), Brown.
13177.002
Swell (+)
Settlement (-)
% of Sample
Thickness
Load
Compliance
(%)
Apparent
Thickness
(in)
(ASTM D 4546) -- Method 'B'
Potential of Cohesive Soils
One-Dimensional Swell or Settlement
Percent Swell / Settlement After Inundation =
Corrected
Deformation
(%)
Pressure (p)
(ksf)

0.6101

0.5880
Final Reading
(in) Void Ratio
-10.00
-9.00
-8.00
-7.00
-6.00
-5.00
-4.00
-3.00
-2.00
-1.00

0.00 0.010 0.100 1.000 10.000
Deformation %
Log Pressure (ksf)
Deformation % - Log Pressure Curve
Inundate With
Distilled Water
Leighton
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Project Name: Tested By: MRV Date: 07/15/21
Project No.: 13177.002 Checked By: MRV Date: 07/16/21
Boring No.: LB-1 Depth (feet): 0.0
Sample No.: B-1
Soil Identification: Silty Sand (SM), Dark Yellowish Brown.

Whole Sample Sample Passing
#4 Whole Sample Sample
passing #4
M M Wt. of Air-Dry Soil + Cont.(g) 2029.2 991.3
2029.2 991.3 Wt. of Dry Soil + Cont. (g) 2004.3 991.3 666.4 666.4 Wt. of Container No._____(g) 666.4 666.4
1337.4 324.9 Moisture Content (%) 1.9 0.0
M
909.4
666.4
243.0
(mm.)
1 1/2"
1"
3/4"
1/2"
3/8"
#4
#8
#16
#30
#50
#100
#200
GRAVEL: 6 %
SAND: 70 %
FINES: 24 %
GROUP SYMBOL: SM N/A
N/A
Remarks:
243.1

67.3 112.8
160.7
207.4

0.075
PAN

20.1 45.3

75.44.750

2.360

1.180

0.600

0.300

0.150
Passing #4 Material After Wet Sieve

37.500
U. S. Sieve Size

25.000

19.000

12.500

9.500
Whole Sample

96.6 100.0

94.4 86.3

23.8 100.0

47.7 34.1
Wt. Air-Dried Soil + Cont.(g)

98.5 Cumulative Weight of Dry Soil Retained (g)
Sample Passing #4

PARTICLE-SIZE DISTRIBUTION (GRADATION)
ASTM D 6913
Container No.:

Lewis/MV Town Center/Geo
Moisture ContentsCalculation of Dry Weights
of SOILS USING SIEVE ANALYSIS
Dry Wt. of Soil (g)

0.0 Wt. of Container (g)
Container No.
100.0

74.8 61.6
Percent Passing
(%)
Wt. of Dry Soil + Container (g)
Wt. of Container (g)
Dry Wt. of Soil Retained on # 200 Sieve (g)

28.0 Cu = D60/D10 =
Cc = (D30)²/(D60*D10) =

6 : 70 : 24
B-1
Jul-21
Boring No.:

Depth (feet): 0.0 Soil Type :

Project Name:

PARTICLE - SIZE

DISTRIBUTION
ASTM D 6913
Soil Identification: Silty Sand (SM), Dark Yellowish Brown.

SM
GR:SA:FI : (%)
Lewis/MV Town Center/Geo
Project No.:

LB-1 Sample No.:
13177.002
SAND

SILT FINE

HYDROMETER

3.0" 1 1/2" 3/4" 3/8" #4 #8 #16 #30 #50 #100 #200 U.S. STANDARD SIEVE OPENING U.S. STANDARD SIEVE NUMBER

GRAVEL FINES

FINE CLAY COARSE COARSE MEDIUM
0 10
20 30
40 50
60 70
80 90
100

0.0010.0100.1001.00010.000100.000

PERCENT FINER BY WEIGHT
PARTICLE - SIZE (mm)
"
Sieve; LB-1, B-1 (07-01-21)
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Project Name: Tested By: MRV Date: 07/15/21
Project No.: 13177.002 Checked By: MRV Date: 07/16/21
Boring No.: LB-3 Depth (feet): 0.0
Sample No.: B-1
Soil Identification: Silty Sand (SM), Dark Yellowish Brown.

Whole Sample Sample Passing
#4 Whole Sample Sample
passing #4
B B Wt. of Air-Dry Soil + Cont.(g) 2024.7 990.3
2024.7 990.3 Wt. of Dry Soil + Cont. (g) 1995.4 990.3 673.2 673.2 Wt. of Container No._____(g) 673.2 673.2
1322.4 317.1 Moisture Content (%) 2.2 0.0
B
903.2
673.2
230.0
(mm.)
1 1/2"
1"
3/4"
1/2"
3/8"
#4
#8
#16
#30
#50
#100
#200
GRAVEL: 4 %
SAND: 69 %
FINES: 27 %
GROUP SYMBOL: SM N/A
N/A
Remarks:
226.9

48.2 78.2
123.5
179.6

0.075
PAN

10.6 25.2

48.04.750

2.360

1.180

0.600

0.300

0.150
Passing #4 Material After Wet Sieve

37.500
U. S. Sieve Size

25.000

19.000

12.500

9.500
Whole Sample

98.1 100.0

96.4 90.6

27.4 100.0

58.9 41.8
Wt. Air-Dried Soil + Cont.(g)

99.2 Cumulative Weight of Dry Soil Retained (g)
Sample Passing #4

PARTICLE-SIZE DISTRIBUTION (GRADATION)
ASTM D 6913
Container No.:

Lewis/MV Town Center/Geo
Moisture ContentsCalculation of Dry Weights
of SOILS USING SIEVE ANALYSIS
Dry Wt. of Soil (g)

0.0 Wt. of Container (g)
Container No.
100.0

81.7 72.6
Percent Passing
(%)
Wt. of Dry Soil + Container (g)
Wt. of Container (g)
Dry Wt. of Soil Retained on # 200 Sieve (g)

19.0 Cu = D60/D10 =
Cc = (D30)²/(D60*D10) =

4 : 69 : 27
B-1
Jul-21
Boring No.:

Depth (feet): 0.0 Soil Type :

Project Name:

PARTICLE - SIZE

DISTRIBUTION
ASTM D 6913
Soil Identification: Silty Sand (SM), Dark Yellowish Brown.

SM
GR:SA:FI : (%)
Lewis/MV Town Center/Geo
Project No.:

LB-3 Sample No.:
13177.002
SAND

SILT FINE

HYDROMETER

3.0" 1 1/2" 3/4" 3/8" #4 #8 #16 #30 #50 #100 #200 U.S. STANDARD SIEVE OPENING U.S. STANDARD SIEVE NUMBER

GRAVEL FINES

FINE CLAY COARSE COARSE MEDIUM
0 10
20 30
40 50
60 70
80 90
100

0.0010.0100.1001.00010.000100.000

PERCENT FINER BY WEIGHT
PARTICLE - SIZE (mm)
"
Sieve; LB-3, B-1 (07-01-21)
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Project Name: Tested By: M. Vinet Date: 7/15/21
Project No. : Checked By: M. Vinet Date: 7/16/21
Boring No.: Depth: 5.0
Sample No. : Location:

Sample Description:

Dry Wt. of Soil + Cont. (gm.)
Wt. of Container No. (gm.)
Dry Wt. of Soil (gm.)
Weight Soil Retained on #4 Sieve
Percent Passing # 4
in distilled water for the period of 24 h or expansion rate < 0.0002 in./h.

Rev. 03-08

SPECIMEN INUNDATION

65.3 Dry Wt. of Soil + Cont. (gm.)

8.5 349.9
326.4

0.461

49.9 200.0
635.0
131.1
Elapsed Time
(min.)
Dial Readings
(in.)

80.149.8
Pressure
(psi)

0.316Total Porosity

2.70 382.5
200.0

13.7 0.316

65.5 EXPANSION INDEX of SOILS
Silty Sand (SM), Dark Yellowish Brown.

MOLDED SPECIMEN

4.01 1.0000
10Container No.

Specimen Diameter (in.)
Wt. Comp. Soil + Mold (gm.)
200.0
N/A
Lewis/MV Town Center/Geo
13177.002
LB-5
B-1
ASTM D 4829

96.9 4.01

2.70 2555.6

0.0 615.0
2555.6

80.2 1.0010
635.0
After TestBefore Test
Wet Wt. of Soil + Cont. (gm.)
10 0.463
Dry Density (pcf)
Wet Density (pcf)
Specific Gravity (Assumed)
Specimen Height (in.)
Wt. of Mold (gm.)
7/15/21
115.4
Moisture Content (%)
Date
10:00
Void Ratio
Pore Volume (cc)
Degree of Saturation (%) [ S meas]
125.2
Time
7/16/21 9:00

1.0 1.0
10:10 1.07/15/21

1.0 1 Expansion Index ( Report ) = Nearest Whole Number or Zero (0) if Initial Height is > than Final Height Add Distilled Water to the Specimen
Wt. of Container (gm.)
115.3

0.5000
10 0.5000

0.50107/16/21
0 1310
Expansion Index (EI meas) = ((Final Rdg - Initial Rdg) / Initial Thick.) x 1000 8:00
1370 0.5010

1.0 Leighton
Project Name: Date: 7/14/21
Project Number: 13177.002 Technician: F. Mina
Boring Number: LB-1 Depth (ft.): 0.0
Sample Number: B-1 Sample Location:

Sample Description: Silty Sand (SM), Dark Yellowish Brown

TEST SPECIMEN A B C
MOISTURE AT COMPACTION % 7.1 8.2 9.2
HEIGHT OF SAMPLE, Inches 2.50 2.50 2.52
DRY DENSITY, pcf 119.8 121.2 120.4
COMPACTOR AIR PRESSURE, psi 200 175 150
EXUDATION PRESSURE, psi 696 348 144
EXPANSION, Inches x 10exp-4 0 0 0
STABILITY Ph 2,000 lbs (160 psi) 23 30 57
TURNS DISPLACEMENT 4.84 5.05 5.55
R-VALUE UNCORRECTED 75 68 45
R-VALUE CORRECTED 75 68 45
DESIGN CALCULATION DATA a b c
GRAVEL EQUIVALENT FACTOR 1.0 1.0 1.0
TRAFFIC INDEX 5.0 5.0 5.0
STABILOMETER THICKNESS, ft. 0.39 0.51 0.88
EXPANSION PRESSURE THICKNESS, ft. 0.00 0.00 0.00

EXPANSION PRESSURE CHART EXUDATION PRESSURE CHART R-VALUE BY EXPANSION: N/A
R-VALUE BY EXUDATION: 65
EQUILIBRIUM R-VALUE: 65

R-VALUE TEST RESULTS
ASTM D 2844
Lewis/MV Town Center/Geo
N/A

0.00 0.50

1.00 1.50

2.00 2.50

3.00 3.50

4.00 0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50 4.00
COVER THICKNESS BY EXPANSION in
feet
COVER THICKNESS BY STABILOMETER in
feet
0 10
20 30
40 50
60 70
80 90
0100200300400500600700800

R-VALUE
EXUDATION PRESSURE (psi)
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Project Name: Lewis/MV Town Center/Geo Tested By : M. Vinet Date: 07/16/21 Project No. : 13177.002 Data Input By: M. Vinet Date: 07/16/21 Boring No. LB-3
Sample No. B-1
Sample Depth (ft) 0.0
100.00
100.00

0.00 0.00
100.00
1 1
850
Timer
45 25.1158

25.1099

0.0059
242.79
243
ml of Extract For Titration (B) 30
ml of AgNO3 Soln. Used in Titration (C) 0.8
PPM of Chloride (C -0.2) * 100 * 30 / B 60
PPM of Chloride, Dry Wt. Basis 60

7.20 21.0
TESTS for SULFATE CONTENT
CHLORIDE CONTENT and pH of SOILS
SULFATE CONTENT, DOT California Test 417, Part II
Soil Identification:

Moisture Content (%)
Temperature °C
pH Value
pH TEST, DOT California Test 643
Dry Weight of Soil + Container (g)
Weight of Container (g)
Duration of Combustion (min)
PPM of Sulfate, Dry Weight Basis
Wt. of Crucible (g)
Silty Sand (SM)
Wt. of Crucible + Residue (g)
Wet Weight of Soil + Container (g)
Wt. of Residue (g) (A)
Beaker No.

Crucible No.

Furnace Temperature (°C)
Time In / Time Out
Weight of Soaked Soil (g)
PPM of Sulfate (A) x 41150
CHLORIDE CONTENT, DOT California Test 422
Leighton
Project Name: Tested By : M. Vinet Date:

Project No. : Data Input By: M. Vinet Date:

Boring No.: Depth (ft.) :

Sample No. :

Soil Identification:*
*California Test 643 requires soil specimens to consist only of portions of samples passing through the No. 8 US Standard Sieve before resistivity testing.  Therefore, this test method may not be representative for coarser materials.

Wt. of Container (g)10.00 6500

0.00 100.00
Moisture Content (%) (MCi)
Wet Wt. of Soil + Cont. (g)
Specimen
No.
1 2
Water
Added (ml)
(Wa)
50 Adjusted
Moisture
Content
(MC) Dry Wt. of Soil + Cont. (g)
6500

1.000
Chloride Content
(ohm-cm)

29.80 Moisture Content Sulfate Content
5 Min. Resistivity
DOT CA Test 643DOT CA Test 417 Part II DOT CA Test 422
(%) (ppm) (ppm)
DOT CA Test 643
4 83
116
149
A
500.003 210023.20
2800
2100 23.2 243 60 7.20 21.0

SOIL RESISTIVITY TEST
DOT CA TEST 643
Temp. (°C)pH
Soil pH
2800
2100
100.00

0.00 MC =(((1+Mci/100)x(Wa/Wt+1))-1)x100
Lewis/MV Town Center/Geo 07/16/21
07/16/21

0.0 13177.002
LB-3
B-1
Container No.

Initial Soil Wt. (g) (Wt)
Box Constant2400 2400
Silty Sand (SM)
Resistance
Reading
(ohm)

16.60 Soil
Resistivity
(ohm-cm)
0 1000
2000
3000
4000
5000
6000
7000

0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0
Soil Resistivity (ohm-cm)
Moisture Content (%)
Minimum resistivity
read here
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Geotechnical Exploration 13177.002
Town Center at Moreno Valley, Moreno Valley, California July 23, 2021 Revised January 17, 2025

APPENDIX C

EARTHWORK AND GRADING SPECIFICATIONS

~ Leighton
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APPENDIX C

GENERAL EARTHWORK AND GRADING SPECIFICATIONS

TABLE OF CONTENTS
Section Page

1.0 GENERAL 1

1.1 Intent 1

1.2 The Geotechnical Consultant of Record 1

1.3 The Earthwork Contractor 2

2.0 PREPARATION OF AREAS TO BE FILLED 2

2.1 Clearing and Grubbing 2

2.2 Processing 3

2.3 Overexcavation 3

2.4 Benching 3

2.5 Evaluation/Acceptance of Fill Areas 3

3.0 FILL MATERIAL 3

3.1 General 3

3.2 Oversize 4

3.3 Import 4

4.0 FILL PLACEMENT AND COMPACTION 4

4.1 Fill Layers 4

4.2 Fill Moisture Conditioning 4

4.3 Compaction of Fill 4

4.4 Compaction of Fill Slopes 4

4.5 Com
paction Testing 5

4.6 Frequency of Compaction Testing 5

4.7 Compaction Test Locations 5

5.0 SUBDRAIN INSTALLATION 5

6.0 EXCAVATION 5

7.0 TRENCH BACKFILLS 6

7.1 Safety 6

7.2 Bedding & Backfill 6

7.3 Lift Thickness 6

7.4 Observation and Testing 6
Standard Details
A - Keying and Benching Rear of Text
Retaining Wall Rear of Text
LEIGHTON AND ASSOCIATES, INC.

General Earthwork and Grading Specifications
-1-

1.0 General

1.1 Intent
These General
Earthwork and Grading Specifications are for the grading and earthwork shown on the approved grading plan(s) and/or indicate d in the geotechnical report(s). These Specifications are a part of the recommendations contained in the geotechnical report(s). In case of conflict, t he specific recommendations in the geotechnical report shall supersede thes e more general Specifications. Observations of the earthwork by the project Ge otechnical Consultant during the course of grading may result in new or revised recommendations that could supersede these specifications or the recommendations in the geotechnical report(s).

1.2 The Geotechnical Consultant of Record
Prior to
commencement of work, the owner shall employ the Geote chnical Consultant of Record (Geotechnical Consultant). The Geotechnic al Consultants shall be responsible for reviewing the approved geotechnical report(s) and accepting the adequacy of the preliminary geotechnical findings, conclusions, and recommendations prior to the commencement of the grading.

Prior to commencement of grading, the Geotechnical Consultant shall review the "work plan" prepared by the Earthwork Contractor (Contractor) a nd schedule sufficient personnel to perform the appropriate level of observation, mapping, and compaction testing.

During the grading and earthwork operations, the Geotechnical Consultant shall observe, map, and document the subsurface exposures to verify the geotechnical design assumptions. If the observed conditions are found to be significantly different than the interpreted assumptions during the design ph ase, the Geotechnical Consultant shall inform the owner, recommend appropriate changes in design to accommodate the observed conditions, and notify th e review agency where required. Subsurface areas to be geotechnically observed , mapped, elevations recorded, and/or tested include natural ground after it has been cleared for receiving fill but before fill is placed, bottoms of all "remedial removal" areas, all key bottoms, and benches made on sloping ground to receive fill.

The Geotechnical Consultant shall observe the moisture-conditioning and processing of the subgrade and fill materials and perform relat ive compaction testing of fill to determine the attained level of compaction. The Geotechnical Consultant shall provide the test results to the owner and the Contractor on a routine and frequent basis.

1.3 The Earthwork Contractor
The Earthwork
Contractor (Contractor) shall be qualified, exper ienced, and knowledgeable in earthwork logistics, preparation and processin g of ground to receive fill, moisture-conditioning and processing of fill, and compacting fill. The Contractor shall review and accept the plans, geotechnical repo rt(s), and these LEIGHTON AND ASSOCIATES, INC.

General Earthwork and Grading Specifications
-2-
Specifications prior to commencement of grading. The Contracto r shall be solely responsible for performing the grading in accordance with the p lans and specifications.

The Contractor shall prepare and submit to the owner and the Geotechnical Consultant a work plan that indicates the sequence of earthwork grading, the number of "spreads" of work and the estimated quantities of dai ly earthwork contemplated for the site prior to commencement of grading. The Contractor shall inform the owner and the Geotechnical Consultant of changes in work schedules and updates to the work plan at least 24 hours in advance of such changes so that appropriate observations and tests can be planned and accomplis hed. The Contractor shall not assume that the Geotechnical Consultant is a w a r e o f a l l grading operations.

The Contractor shall have the sole responsibility to provide adequate equipment and methods to accomplish the earthwork in accordance with the applicable grading codes and agency ordinances, these Specifications, and the recommenda tions in the approved geotechnical report(s) and grading plan(s). If, in the opinion of the Geotechnical Consultant, unsatisfactory conditions, such as unsuitable soil, improper moisture condition, inadequate compaction, insufficient buttress key size, adverse weather, etc., are resulting in a quality of work less than req uired in these specifications, the Geotechnical Consultant shall reject the work and may recommend to the owner that construction be stopped until the conditions are rectified.

2.0 Preparation of Areas to be Filled

2.1 Clearing and Grubbing

Vegetation, such as brush, grass, roots, and other deleterious material shall be sufficiently removed and properly disposed of in a method acceptable to the owner, governing agencies, and the Geotechnical Consultant.

The Geotechnical Consultant shall evaluate the extent of these removals depending on specific site conditions. Earth fill material shall not contain more than 1 percent of organic materials (by volume). No fill lift shall contain more than 5 percent of organic matter. Nesting of the organic materials shall not be allowed.

If potentially hazardous materials are encountered, the Contr actor shall stop work in the affected area, and a hazardous material specialist shall be informed immediately for proper evaluation and handling of these materia l s p r i o r t o continuing to work in that area.

As presently defined by the State of California, most refined petroleum products (gasoline, diesel fuel, motor oil, grease, coolant, etc.) have chemical constituents that are considered to be hazardous waste. As such, the indiscriminate dumping or spillage of these fluids onto the ground may constitute a mi sdemeanor, punishable by fines and/or imprisonment, and shall not be allowed.

LEIGHTON AND ASSOCIATES, INC.

General Earthwork and Grading Specifications
-3-

2.2 Processing

Existing ground that has been declared satisfactory for support of fill by the Geotechnical Consultant shall be scarified to a minimum depth of 6 inches.

Existing ground that is not satisfactory shall be overexcavated as specified in the following section. Scarification shall continue until soils are broken down and free of large clay lumps or clods and the working surface is reasona bly uniform, flat, and free of uneven features that would inhibit uniform compaction.

2.3 Overexcavation

In addition to removals and overexcavations recommended in the approved geotechnical report(s) and the grading plan, soft, loose, dry, saturated, spongy, organic-rich, highly fractured or otherwise unsuitable ground s hall be overexcavated to competent ground as evaluated by the Geotechnical Consultant during grading.

2.4 Benching

Where fills are to be placed on ground with slopes steeper than 5:1 (horizontal to vertical units), the ground shall be stepped or benched. The l owest bench or key shall be a minimum of 15 feet wide and at least 2 feet deep, in to competent material as evaluated by the Geotechnical Consultant. Other be nches shall be excavated a minimum height of 4 feet into competent material or as otherwise recommended by the Geotechnical Consultant. Fill placed on ground sloping flatter than 5:1 shall also be benched or otherwise overexcavated to pr ovide a flat subgrade for the fill.

2.5 Evaluation/Acceptance of Fill Areas

All areas to receive fill, including removal and processed area s, 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 Geotechni cal Consultant prior to fill placement. A licensed surveyor shall provide the survey control for determining elevations of processed areas, keys, and benches.

3.0 Fill Material

3.1 General

Material to be used as fill shall be essentially free of organi c matter and other deleterious substances evaluated and accepted by the Geotechnic al Consultant prior to placement. Soils of poor quality, such as those with u nacceptable gradation, high expansion potential, or low strength shall be p laced in areas acceptable to the Geotechnical Consultant or mixed with other s oils to achieve satisfactory fill material.

LEIGHTON AND ASSOCIATES, INC.

General Earthwork and Grading Specifications
-4-

3.2 Oversize
Oversize m
aterial defined as rock, or other irreducible materia l with a maximum dimension greater than 8 inches, shall not be buried or placed in fill unless location, materials, and placement methods are specifically acc epted by the Geotechnical Consultant. Placement operations shall be such that nesting of oversized material does not occur and such that oversize materi al is completely surrounded by compacted or densified fill. Oversize material s hall not be placed within 10 vertical feet of finish grade or within 2 feet of fut ure utilities or underground construction.

3.3 Import
If importing
of fill material is required for grading, proposed import material shall meet the requirements of Section 3.1. The potential import source shall be given to the Geotechnical Consultant at least 48 hours (2 working days) before importing begins so that its suitability can be determined and appropriate tests performed.

4.0 Fill Placement and Compaction

4.1 Fill Layers
Approved fill
material shall be placed in areas prepared to receive fill (per Section 3.0) in near-horizontal layers not exceeding 8 inches i n loose thickness.

The Geotechnical Consultant may accept thicker layers if testin g indicates the grading procedures can adequately compact the thicker layers. Each layer shall be spread evenly and mixed thoroughly to attain relative unifor mity of material and moisture throughout.

4.2 Fill 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 over optimum. Maximum density and optimum soil moisture content tests shall be performed in accordance with the American Society of Testing and Materials (ASTM Test Method D1557).

4.3 Compaction of Fill
After each
layer has been moisture-conditioned, mixed, and even ly spread, it shall be uniformly compacted to not less than 90 percent of max imum dry density (ASTM Test Method D1557). Compaction equipment shall be adequa tely sized and be either specifically designed for soil compaction or of p roven reliability to efficiently achieve the specified level of compaction with uniformity.

4.4 Compaction of Fill Slopes
In addition
to normal compaction procedures specified above, compaction of slopes shall be accomplished by backrolling of slopes with sheepsfoot rollers at increments of 3 to 4 feet in fill elevation, or by other methods producing satisfactory results acceptable to the Geotechnical Consultant. Upon completion LEIGHTON AND ASSOCIATES, INC.

General Earthwork and Grading Specifications
-5-
of grading, relative compaction of the fill, out to the slope face, shall be at least 90 percent of maximum density per ASTM Test Method D1557.

4.5 Compaction Testing
Field-tests for
moisture content and relative compaction of the fill soils shall be performed by the Geotechnical Consultant. Location and frequency of tests shall be at the Consultant's discretion based on field conditions enc ountered.

Compaction test locations will not necessarily be selected on a random basis.

Test locations shall be selected to verify adequacy of compacti on levels in areas that are judged to be prone to inadequate compaction (such as c lose to slope faces and at the fill/bedrock benches).

4.6 Frequency of Compaction Testing
Tests s
hall be taken at intervals not exceeding 2 feet in verti cal rise and/or 1,000 cubic yards of compacted fill soils embankment. In addition, as a guideline, at least one test shall be taken on slope faces for each 5,000 square feet of slope face and/or each 10 feet of vertical height of slope. Th e Contractor shall assure that fill construction is such that the testing schedule can be accomplished by the Geotechnical Consultant. The Contractor shall stop or slow down the earthwork construction if these minimum standards are not met.

4.7 Compaction Test Locations
The Geotechnical
Consultant shall document the approximate elevation and horizontal coordinates of each test location. The Contractor shall coordinate with the project surveyor to assure that sufficient grade stakes are established so that the Geotechnical Consultant can determine the test locations with sufficient accuracy. At a minimum, two grade stakes within a horizontal distance of 100 feet and vertically less than 5 feet apart from potential test locations shall be provided.

5.0 Subdrain Installation
S
ubdrain systems shall be installed in accordance with the approved geotechnical report(s), the grading plan. The Geotechnical Consultant may recommend additional subdrains and/or changes in subdrain extent, location, grade, o r material depending on conditions encountered during grading. All subdrains shall be s urveyed by a land surveyor/civil engineer for line and grade after installation a nd prior to burial. Sufficient time should be allowed by the Contractor for these surveys.

6.0 Excavation
E
xcavations, as well as over-excavation for remedial purposes, shall be evaluated by the Geotechnical Consultant during grading. Remedial removal depths shown on geotechnical plans are estimates only. The actual extent of rem oval shall be determined by the Geotechnical Consultant based on the field evaluation of exposed conditions during grading. Where fill-over-cut slopes are to be graded, t he cut portion of the slope LEIGHTON AND ASSOCIATES, INC.

General Earthwork and Grading Specifications
-6-
shall be made, evaluated, and accepted by the Geotechnical Consultant prior to placement of materials for construction of the fill portion of the slope, unless otherwise recommended by the Geotechnical Consultant.

7.0 Trench Backfills

7.1 Safety
The Contractor
shall follow all OSHA and Cal/OSHA requirements for safety of trench excavations.

7.2 Bedding and Backfill
All bedding
and backfill of utility trenches shall be performed in accordance with the applicable provisions of Standard Specifications of Public Work s Construction.

Bedding material shall have a Sand Equivalent greater than 30 ( SE>30). The bedding shall be placed to 1 foot over the top of the conduit and densified by jetting. Backfill shall be placed and densified to a minimum of 90 percent of relative compaction from 1 foot above the top of the conduit to the surface.

The Geotechnical Consultant shall test the trench backfill fo r relative compaction.

At least one test should be made for every 300 feet of trench and 2 feet of fill.

7.3 Lift Thickness
Lift thickness
of trench backfill shall not exceed those allowe d in the Standard Specifications of Public Works Construction unless the Contract or can demonstrate to the Geotechnical Consultant that the fill lift c an be compacted to the minimum relative compaction by his alternative equipment and method.

7.4 Observation and Testing
The jetting
of the bedding around the conduits shall be observe d by the Geotechnical Consultant.

FILL SLOPE
PROJECTED PLANE 1: 1
(HORIZONTAL: VERTICAL)

MAXIMUM FROM TOE

OF SLOPE TO

APPROVED GROUND

EXISTING

GROUND SURFACE

FILL-OVER-CUT SLOPE
-

CUT-OVER-ALL SLOPE

PROJECTED PLANE
1 TO 1 MAXIMUM

FROM TOE OF SLOPE

TO APPROVED GROUND

KEYING AND BENCHING
REMOVE

UNSUITABLE

MATERIAL
REMOVE

UNSUITABLE

MATERIAL

UT FACE SHALL BE

CONSTRUCTED PRIOR

TO FILL PLACEMENT
REMOVE

UNSUITABLE

MATERIAL

BENCHING SHALL BE DONE WHEN SLOPE'S
ANGLE IS EQUAL TO OR GREATER THAN 5: 1.

MINIMUM BENCH HEIGHT SHALL BE 4 FEET
AND MINIMUM FILL WIDTH SHALL BE 9 FEET.

GENERAL EARTHWORK AND GRADING

SPECIFICATIONS

STANDARD DETAILS A
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-----------------· -------------------------------------------------------------------------------------------------~-:-:-:-:coMPACTErr-:-:-::::~ ----:-:-:-:-:-:-:-:-~--FILL-:-:-:-;c:~-:-~ ---------------~----- -____________________ -------------~-__________________ _ _ ____ __..., __ _ -------- ----------------- ------- ---- - - ~"'"""'r
-- --- ------ ------
!!"'_-.:.-_-____ _
----- -
:::::-:~-:--I BENCH -~--------- • BENCH HEIGHT
::::::°=:::::::: ( 4 FEET TYPICAL) MIN,--_-__
15 FEET MIN. I
2 FEET MIN. • LOWEST •

KEY DEPTH BENCH (KEY)
~JJJf :=::-:-::.

BENCH HEIGHT
.- ( 4 FEET TYPICAL)
---

OVERBUILD AN

TRIM BACK
°%-Mfr,J;:-_
, 5 FEET MIN., I
LOWEST

BENCH (KEY)

CUT FACE
SHALL BE CONSTRUCTED PRIOR TO / .,,,.

FILL PLACEMENT TO ALLOW VIEWING / /

OF GEOLOGIC CONDITIONS / /
f' /
EXISTING- -,., f /
GROUND E..:::.-_; -
SURF A~~-f ::::~:~:
---=i.=~======~!i_~====--=
DESIGN SLOPE-~.;,;::
:__ BENCH HEIGHT
-_-:-:::=:::: ( 4 FEET TYPICAL)
-.Fl --:::
115 FEET MIN. I
2 FEET MIN. • LOWEST '

KEY DEPTH BENCH (KEY)

RETAINING WALL BACKFILL AND SUBDRAIN DETAIL

WITH PROPER

SURFACE DRAINAGE
SLOPE

OR LEVEL
CLASS 2 PERMEABLE

WEEP HOLE

WATERPROOFING
(SEE GENERAL NOTES)

LEVEL OR
SLOPE
12"

FILTER MATERIAL
NATIVE
¼ TO 1½ INCH SIZE GRAVEL

WRAPPED IN FILTER FABRIC

LEVEL OR
SLOPE

WEEP HOLE
SLOPE

OR LEVEL
12"

WITH PROPER

SURFACE DRAINAGE
4 INCH DIAMETER

PERFORATED PIPE
(SEE NOTE 3)

FILTER FABRIC
OPTION 1: PIPE SURROUNDED WITH
CLASS 2 PERMEABLE MATERIAL OPTION 2: GRAVEL WRAPPED

IN FILTER FABRIC
SUBDRAIN OPTIONS AND BACKFILL WHEN NATIVE MATERIAL HAS EXPANSION INDEX OF <50 Sieve Size
1"
3/4"
3/8"
No. 4
No. 8
No. 30
No. 50
No. 200
Percent Passing
100
90-100
40-100
25-40
18-33
5-15
0-7
0-3
Class 2 Filter Permeable Material Gradation
Per Caltrans Specifications
(SEE NOTE 5)
12" MINIMUM
(SEE GRADATION)

WATERPROOFING
(SEE GENERAL NOTES)
(SEE NOTE 4)
12" MINIMUM
NATIVE
FOR WALLS 6 FEET OR LESS IN HEIGHT
(SEE NOTE 5)
WHEN NATIVE MATERIAL HAS EXPANSION INDEX OF <50
GENERAL NOTES:
* Waterproofing should be provided where moisture nuisance problem through the wall is undesirable. * Water proofing of the walls is not under purview of the geotechnical engineer * All drains should have a gradient of 1 percent minimum *Outlet portion of the subdrain should have a 4-inch diameter solid pipe discharged into a suitable disposal area designed by the project engineer. The subdrain pipe should be accessible for maintenance (rodding) *Other subdrain backfill options are subject to the review by the geotechnical engineer and modification of design parameters.

Notes:
1) Sand should have a sand equivalent of 30 or greater and may be densified by water jetting. 2) 1 Cu. ft. per ft. of 1/4- to 1 1/2-inch size gravel wrapped in filter fabric 3) Pipe type should be ASTM D1527 Acrylonitrile Butadiene Styrene (ABS) SDR35 or ASTM D1785 Polyvinyl Chloride plastic (PVC), Schedule 40, Armco A2000 PVC, or approved equivalent. Pipe should be installed with perforations down. Perforations should be 3/8 inch in diameter placed at the ends of a 120-degree arc in two rows at 3-inch on center (staggered) 4) Filter fabric should be Mirafi 140NC or approved equivalent. 5) Weephole should be 3-inch minimum diameter and provided at 10-foot maximum intervals. If exposure is permitted, weepholes should be located 12 inches above finished grade. If exposure is not permitted such as for a wall adjacent to a sidewalk/curb, a pipe under the sidewalk to be discharged through the curb face or equivalent should be provided. For a basement-type wall, a proper subdrain outlet system should be provided.
6) Retaining wall plans should be reviewed and approved by the geotechnical engineer. 7) Walls over six feet in height are subject to a special review by the geotechnical engineer and modifications to the above requirements.

V:\DRAFTING\TEMPLATES\STANDARD-FIGURES\ALL-STANDARD-FIGURES.DWG (08-02-21 9:07:35AM) Plotted by: btran •,
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Geotechnical Exploration 13177.002
Town Center at Moreno Valley, Moreno Valley, California July 23, 2021 Revised January 17, 2025

APPENDIX D

GBA IMPORTANT INFORMATION ABOUT THIS

GEOTECHNICAL ENGINEERING REPORT

~ Leighton
a verdantas company
Geotechnical-Engineering Report
Important Information about This
Subsurface problems are a principal cause of construction delays, cost overruns, claims, and disputes.

While you cannot eliminate all such risks, you can manage them. The following information is provided to help.

The Geoprofessional Business Association (GBA)
has prepared this advisory to help you – assumedly
a client representative – interpret and apply this
geotechnical-engineering report as effectively as
possible. In that way, you can benefit from a lowered
exposure to problems associated with subsurface
conditions at project sites and development of
them that, for decades, have been a principal cause
of construction delays, cost overruns, claims,
and disputes. If you have questions or want more
information about any of the issues discussed herein,
contact your GBA-member geotechnical engineer.

Active engagement in GBA exposes geotechnical
engineers to a wide array of risk-confrontation
techniques that can be of genuine benefit for
everyone involved with a construction project.

Understand the Geotechnical-Engineering Services
Provided for this Report
Geotechnical-engineering services typically include the planning, collection, interpretation, and analysis of exploratory data from widely spaced borings and/or test pits. Field data are combined with results from laboratory tests of soil and rock samples obtained from field exploration (if applicable), observations made during site reconnaissance, and historical information to form one or more models of the expected subsurface conditions beneath the site. Local geology and alterations of the site surface and subsurface by previous and proposed construction are also important considerations. Geotechnical engineers apply their engineering training, experience, and judgment to adapt the requirements of the prospective project to the subsurface model(s). Estimates are made of the subsurface conditions that will likely be exposed during construction as well as the expected performance of foundations and other structures being planned and/or affected by construction activities.

The culmination of these geotechnical-engineering services is typically a geotechnical-engineering report providing the data obtained, a discussion of the subsurface model(s), the engineering and geologic engineering assessments and analyses made, and the recommendations developed to satisfy the given requirements of the project. These reports may be titled investigations, explorations, studies, assessments, or evaluations.

Regardless of the title used, the geotechnical-engineering report is an engineering interpretation of the subsurface conditions within the context of the project and does not represent a close examination, systematic inquiry, or thorough investigation of all site and subsurface conditions.

Geotechnical-Engineering Services are Performed
for Specific Purposes, Persons, and Projects,
and At Specific Times
Geotechnical engineers structure their services to meet the specific needs, goals, and risk management preferences of their clients. A geotechnical-engineering study conducted for a given civil engineer will not likely meet the needs of a civil-works constructor or even a different civil engineer. Because each geotechnical-engineering study is unique, each geotechnical-engineering report is unique, prepared solely for the client.

Likewise, geotechnical-engineering services are performed for a specific project and purpose. For example, it is unlikely that a geotechnical- engineering study for a refrigerated warehouse will be the same as one prepared for a parking garage; and a few borings drilled during a preliminary study to evaluate site feasibility will not be adequate to develop geotechnical design recommendations for the project.

Do not rely on this report if your geotechnical engineer prepared it:
• f or a different client;
• f or a different project or purpose;
• f or a different site (that may or may not include all or a portion of the original site); or
• b efore important events occurred at the site or adjacent to it; e.g., man-made events like construction or environmental remediation, or natural events like floods, droughts, earthquakes, or groundwater fluctuations.

Note, too, the reliability of a geotechnical-engineering report can be affected by the passage of time, because of factors like changed subsurface conditions; new or modified codes, standards, or regulations; or new techniques or tools. If you are the least bit uncertain about the continued reliability of this report, contact your geotechnical engineer before applying the recommendations in it. A minor amount of additional testing or analysis after the passage of time – if any is required at all – could prevent major problems.

Read this Report in Full
Costly problems have occurred because those relying on a geotechnical- engineering report did not read the report in its entirety. Do not rely on an executive summary. Do not read selective elements only. Read and refer to the report in full.

You Need to Inform Your Geotechnical Engineer
About Change
Y our geotechnical engineer considered unique, project-specific factors when developing the scope of study behind this report and developing the confirmation-dependent recommendations the report conveys.

Typical changes that could erode the reliability of this report include those that affect:
• t he site’s size or shape;
• t he elevation, configuration, location, orientation, function or weight of the proposed structure and
the desired performance criteria;
• t he composition of the design team; or
• p roject ownership.

As a general rule, always inform your geotechnical engineer of project or site changes – even minor ones – and request an assessment of their impact. The geotechnical engineer who prepared this report cannot accept responsibility or liability for problems that arise because the geotechnical engineer was not informed about developments the engineer otherwise would have considered.

Most of the “Findings” Related in This Report
Are Professional Opinions
Before construction begins, geotechnical engineers explore a site’s subsurface using various sampling and testing procedures. Geotechnical engineers can observe actual subsurface conditions only at those specific locations where sampling and testing is performed. The data derived from that sampling and testing were reviewed by your geotechnical engineer, who then applied professional judgement to form opinions about subsurface conditions throughout the site. Actual sitewide-subsurface conditions may differ – maybe significantly – from those indicated in this report. Confront that risk by retaining your geotechnical engineer to serve on the design team through project completion to obtain informed guidance quickly, whenever needed.

This Report’s Recommendations Are
Confirmation-Dependent
The recommendations included in this report – including any options or alternatives – are confirmation-dependent. In other words, they are not final, because the geotechnical engineer who developed them relied heavily on judgement and opinion to do so. Y our geotechnical engineer can finalize the recommendations only after observing actual subsurface conditions exposed during construction. If through observation your geotechnical engineer confirms that the conditions assumed to exist actually do exist, the recommendations can be relied upon, assuming no other changes have occurred. The geotechnical engineer who prepared this report cannot assume responsibility or liability for confirmation-dependent recommendations if you fail to retain that engineer to perform construction observation.

This Report Could Be Misinterpreted
Other design professionals’ misinterpretation of geotechnical- engineering reports has resulted in costly problems. Confront that risk by having your geotechnical engineer serve as a continuing member of the design team, to:
• co nfer with other design-team members;
• h elp develop specifications;
• r eview pertinent elements of other design professionals’ plans and specifications; and
• b e available whenever geotechnical-engineering guidance is needed.

Y ou should also confront the risk of constructors misinterpreting this report. Do so by retaining your geotechnical engineer to participate in prebid and preconstruction conferences and to perform construction- phase observations.

Give Constructors a Complete Report and Guidance
Some owners and design professionals mistakenly believe they can shift unanticipated-subsurface-conditions liability to constructors by limiting the information they provide for bid preparation. To help prevent the costly, contentious problems this practice has caused, include the complete geotechnical-engineering report, along with any attachments or appendices, with your contract documents, but be certain to note conspicuously that you’ve included the material for information purposes only. To avoid misunderstanding, you may also want to note that “informational purposes” means constructors have no right to rely on the interpretations, opinions, conclusions, or recommendations in the report. Be certain that constructors know they may learn about specific project requirements, including options selected from the report, only from the design drawings and specifications. Remind constructors that they may perform their own studies if they want to, and be sure to allow enough time to permit them to do so. Only then might you be in a position to give constructors the information available to you, while requiring them to at least share some of the financial responsibilities stemming from unanticipated conditions. Conducting prebid and preconstruction conferences can also be valuable in this respect.

Read Responsibility Provisions Closely
Some client representatives, design professionals, and constructors do not realize that geotechnical engineering is far less exact than other engineering disciplines. This happens in part because soil and rock on project sites are typically heterogeneous and not manufactured materials with well-defined engineering properties like steel and concrete. That lack of understanding has nurtured unrealistic expectations that have resulted in disappointments, delays, cost overruns, claims, and disputes.

To confront that risk, geotechnical engineers commonly include explanatory provisions in their reports. Sometimes labeled “limitations, ” many of these provisions indicate where geotechnical engineers’ responsibilities begin and end, to help others recognize their own responsibilities and risks. Read these provisions closely. Ask questions.

Y our geotechnical engineer should respond fully and frankly.

Geoenvironmental Concerns Are Not Covered
The personnel, equipment, and techniques used to perform an environmental study – e.g., a “phase-one” or “phase-two” environmental site assessment – differ significantly from those used to perform a geotechnical-engineering study. For that reason, a geotechnical-engineering report does not usually provide environmental findings, conclusions, or recommendations; e.g., about the likelihood of encountering underground storage tanks or regulated contaminants. Unanticipated subsurface environmental problems have led to project failures. If you have not obtained your own environmental information about the project site, ask your geotechnical consultant for a recommendation on how to find environmental risk-management guidance.

Obtain Professional Assistance to Deal with
Moisture Infiltration and Mold
While your geotechnical engineer may have addressed groundwater, water infiltration, or similar issues in this report, the engineer’s services were not designed, conducted, or intended to prevent migration of moisture – including water vapor – from the soil through building slabs and walls and into the building interior, where it can cause mold growth and material-performance deficiencies.

Accordingly, proper implementation of the geotechnical engineer’s recommendations will not of itself be sufficient to prevent moisture infiltration. Confront the risk of moisture infiltration by including building-envelope or mold specialists on the design team.

Geotechnical engineers are not building-envelope or mold specialists.

Copyright 2019 by Geoprofessional Business Association (GBA). Duplication, reproduction, or copying of this document, in whole or in part, by any means whatsoever, is strictly prohibited, except with GBA ’s specific written permission. Excerpting, quoting, or otherwise extracting wording from this document is permitted only with the express written permission of GBA, and only for purposes of scholarly research or book review. Only members of GBA may use this document or its wording as a complement to or as an element of a report of any kind.

Any other firm, individual, or other entity that so uses this document without being a GBA member could be committing negligent or intentional (fraudulent) misrepresentation.

Telephone: 301/565-2733
e-mail: [email protected] www.geoprofessional.org Marc
h 6, 2024
Project No. 13177.002
Lewis Land Developers, LLC
1156 North Mountain Avenue
Upland, CA 91786
Attention: M r. Joseph Edwards
Subject: Geotechnical Addendum #1
Town Center at Moreno Valley
Northwest Corner or Alessandro Boulevard and Nason Street Mor
eno Valley, California
References: California Building Code, 2022, California Code of Regulations Title 24, Part 2, Volume 2.

Leighton Consulting, Inc., 2021, Town Center at Moreno Valley, Geotechnical Exploration, Northwest Corner of Alessandro Boulevard and Nason Street , Moreno Valley, California, dated July 23.

In acc
ordance with your request and authorization, this addendum report is to confirm that our recommendations included in the above referenced geotechnical report remain applicable based on the 2022 California Building Code (CBC). However, per Supplement 3 to ASCE 7-16, the 2022 CBC seismic coefficients have been updated and are listed in table below:

CBC Site-Specific Seismic Coefficients
CBC Categorization/Coefficient Value (g)
Site Longitude (decimal degrees) -117.1940
Site Latitude (decimal degrees) 33.9208
Site Class Definition D
Mapped Spectral Response Acceleration at 0.2s Period, Ss 1.87 Mapped Spectral Response Acceleration at 1s Period, S1 0.74 Short Period Site Coefficient at 0.2s Period, Fa 1.0
Long Period Site Coefficient at 1s Period, Fv 1.7
Adjusted Spectral Response Acceleration at 0.2s Period, SMS 1.87 Adjusted Spectral Response Acceleration at 1s Period, SM1 1.89* Design Spectral Response Acceleration at 0.2s Period, SDS 1.25 Design Spectral Response Acceleration at 1s Period, SD1 1.25* Site-Specific Modified Peak Ground Acceleration, PGAm 0.87 *Note: The seismic parameters SM1 and SD1 are increased by 50% (Site Class D) per Supplement 3 of ASCE 7-16. The project structural engineer should confirm if a site–specific ground motion analysis is needed ~ Leighton --a verdantas company
41715 Enterprise Circle N, Suite 103, Temecula, CA 92590 www.leightongroup.com
Leighton and Associates, Inc.

T: 951 .296.0530
Geotechnical Addendum #1 (Revised) 13177.002
Town Center at Moreno Valley March 6, 2024
2 If you have any questions regarding this report, please contact this office at your convenience.

Respectfully submitted,
LEIGHTON AND ASSOCIATES, INC.

Brent A. Adam
Senior Project Geologist
Ext. 8923, [email protected]
Bashir Saiid, PE
Associate Engineer
Ext. 8927, [email protected]
Di
stribution: (1) Addressee (PDF via email)
~ Leighton
a verdantas company