CA FTBR FSTR(2) Final Geotech Report.pdf

SUBMITTED TO:

HDR Engineering, Inc.

1670 Broadway, Suite 3400 Denver, Colorado 80202

BY:

Shannon & Wilson, Inc.

1321 Bannock St. Suite 200 Denver, Colorado 80204

(303) 825-3800 www.shannonwilson.com

GEOTECHNICAL DESIGN REPORT

CA FTBR FSTR (2)

Folsom South Trail Improvements

SACRAMENTO COUNTY, CALIFORNIA

December 2019

Shannon & Wilson No: 103447-001

Geotechnical Design Report

103447-001 December 2019 ii

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CONTENTS

1 Introduction

2 Project and Site Description

3 Subsurface Explorations and Laboratory Testing

3.1 Field Investigation

3.2 Geotechnical Laboratory Testing

4 Regional Geology and Subsurface Conditions

4.1 Regional Geology

4.2 Subsurface Conditions

4.3 Groundwater

5 Geologic Hazard Evaluation

5.1 Seismic Hazards

5.1.1 General

5.1.2 Fault Surface Rupture

5.1.3 Seismic Ground Motions

5.1.4 Liquefaction

5.1.5 Seismic Compression

5.2 Corrosion

6 Foundation Recommendations

6.1 Seismic Design Criteria

6.2 Bearing Resistance

6.3 Lateral Earth Pressures

6.3.1 Lateral Resistance

6.3.2 Wall Drainage

7 Construction Considerations

7.1 Subgrade Preparation

7.2 Fill Placement

8 Closure

9 References iii

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Exhibits Exhibit 6‐1: Seismic Design Ground Motion Parameters

Exhibit 6‐2: Estimated Bearing Capacities

Exhibit 6‐3: Recommended Lateral Earth Pressure Design Parameters

Exhibit 6‐4: Recommended Lateral Resistance Design Parameters

Exhibit 7‐1: Recommended Materials for Construction

Figures Figure 1: Vicinity Map

Figure 2: Site and Exploration Plan

Figure 3: Recommended Surcharge Loading for Temporary and Permanent Walls

Appendices Appendix A: Subsurface Explorations

Appendix B: Laboratory Test Results

Appendix C: Exploration Photographs

Important Information

Geotechnical Design Report

103447-001 December 2019

1 INTRODUCTION

This report summarizes the results of our subsurface exploration and laboratory testing program and presents geotechnical design recommendations and construction considerations for the proposed pedestrian bridge associated with the Folsom South Trail

Improvements Project (the Project) in Sacramento County, California. Our services were completed in general accordance with our Task Order Agreement No. 013/10001000043376 with HDR Engineering, Inc. (HDR) dated July 25, 2019. Our conclusions and recommendations in this report are based on:

The limitations of our approved scope, schedule, and budget described in our contract;

Our understanding of the Project and information provided by HDR;

Subsurface conditions observed in the borings at the time our explorations were completed; and

The results of testing performed on samples collected from the explorations.

The objective of our geotechnical studies was to provide recommendations and construction considerations, as presented herein, for the proposed pedestrian bridge. The authorized scope of services was based on this objective and this report should not be used for other purposes without Shannon & Wilson, Inc.’s (Shannon & Wilson’s) review. If a service is not specifically indicated in this report, do not assume that it was performed.

2 PROJECT AND SITE DESCRIPTION

The Project is located along the Folsom South Canal Trail in Sacramento County, California

(Figures 1 and 2). The Folsom South Canal Trail is operated by the U.S. Bureau of

Reclamation. The current trail traverses through an unnamed ditch as a low water crossing.

The proposed work for the project consists of adding a new pedestrian bridge for the Canal

Trail over the unnamed ditch. We understand that the proposed pedestrian bridge will consist of a prefabricated single span structure founded on shallow foundations. Based on plans provided by HDR (2019), the bridge will be approximately 90 feet long and approximately 11 feet wide. The grades will remain consistent with the current canal trail elevation and the proposed bridge abutments will be founded on the embankment slopes.

Refer to Figure 2 for a project map with the bridge location.

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3 SUBSURFACE EXPLORATIONS AND LABORATORY

TESTING

3.1 Field Investigation

Shannon & Wilson conducted a field exploration program on August 5 and 6, 2019, to explore subsurface conditions at the Project site. The subsurface exploration program consisted of drilling and sampling two borings (designated SW‐01 and SW‐02). The locations of the borings are shown in Figure 2.

Appendix A presents a discussion of the drilling and sampling procedures used to complete the borings. Appendix A also presents the individual exploration logs and an explanation of the symbols and terminology used. Photographs of the drilling locations are included in

Appendix C.

3.2 Geotechnical Laboratory Testing

Geotechnical laboratory tests were completed on selected samples retrieved from the borings to estimate index and engineering properties. Index tests included natural water content, grain size analysis, percent fines, and Atterberg limits. Engineering properties tests included corrosion tests. Laboratory test results and a discussion of the testing procedures are included in Appendix B. The natural water content, fines content, and Atterberg limits are also shown on the individual boring logs included in Appendix A.

4 REGIONAL GEOLOGY AND SUBSURFACE

CONDITIONS

4.1 Regional Geology

Geologic mapping in the area shows the site is underlain by Quaternary Great Valley

Alluvial Fan deposits (Strand and Koenig, 1965).

4.2 Subsurface Conditions

Boring SW‐01 was drilled at the north abutment of the proposed bridge location and encountered loose to medium dense, clayey sand over very stiff, sandy lean clay to a depth of 15 feet. Dense to very dense gravel and sand with varying percentages of silt was then encountered to a depth of 53 feet. Very stiff to hard clay and silt was then encountered to the termination depth of the boring at 76.5 feet.

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Boring SW‐02, located at the south abutment, encountered loose to medium dense, clayey sand with gravel to a depth of 7 feet overlying interbedded medium dense to dense silt and stiff to very stiff clay with varying percentages of sand. At a depth of 18 feet, very dense gravel and sand with varying percentages of silt was encountered to a depth of 48 feet, underlain by stiff to hard silt to the termination depth of the boring at 76.5 feet.

The explorations were performed to evaluate geotechnical soil conditions at the Project site.

Our observations are specific to the locations, depths, and times noted on the logs and may not be applicable to all areas of the site. No amount of explorations or testing can precisely predict the characteristics, quality, or distribution of subsurface and site conditions.

Potential variation includes, but is not limited to:

The conditions between explorations may be different.

The passage of time or intervening causes (natural and manmade) may result in changes to site and subsurface conditions.

If conditions different from those described herein are encountered during construction, we should review our description of the subsurface conditions and reconsider our conclusions and recommendations.

4.3 Groundwater

During drilling, perched groundwater was encountered at a depth of 45 feet in boring

SW‐01. Groundwater was not encountered in boring SW‐02. The groundwater level at the time of drilling is noted on each boring log included in Appendix A. Groundwater fluctuations are likely and will depend on seasonal variations, local precipitation and runoff, and other factors, but will primarily be influenced by water levels in the adjacent unnamed ditch.

5 GEOLOGIC HAZARD EVALUATION

5.1 Seismic Hazards

5.1.1 General

The project site is located within the seismically‐active northern California area. Potential seismic hazards include: fault surface rupture, seismic compression, and liquefaction. The following subsections describe our evaluation of the site seismic design criteria and potential seismically‐induced hazards based on the design criteria.

Geotechnical Design Report

103447-001 December 2019

5.1.2 Fault Surface Rupture

Based on a recent geologic map by the U.S. Geological Survey (USGS), the nearest faults to the proposed project are the Midland Fault Zone and the Foothills Fault System, approximately 30 miles to the west and 20 miles to the east of the site, respectively (Bryant, 2017). Taking into consideration the distance to known fault zones, the potential for fault rupture to impact the Project is low, in our opinion.

5.1.3 Seismic Ground Motions

We anticipate the site will experience strong ground shaking during an earthquake along faults in the region. The intensity of earthquake ground motion and seismic hazards that may impact the project site will depend on the characteristics of the generating fault, distance to the earthquake fault, earthquake magnitude, earthquake duration, and site‐ specific geologic conditions. Likely sources for strong ground motion are known active faults. Ground motions may be amplified or attenuated at the site depending on the level of ground shaking in the underlying bedrock, underlying soil type, depth to bedrock, and other factors.

To mitigate the potential for future damage from strong seismic events, we recommend the structures be analyzed using seismic design criteria in the governing design codes, as discussed in Section 6.1.

5.1.4 Liquefaction

Soil liquefaction is a phenomenon in which pore pressure in loose, saturated, granular soil increases during ground shaking to a level near the initial effective stress, resulting in a reduction of shear strength of the soil (quicksand‐like conditions). The loss in shear strength may generate ground settlement, lateral spreading (ground movement on gentle slopes), bearing capacity failure, and/or landslides. Liquefaction potential is greatest where loose granular soil (sand and nonplastic silt) is present below groundwater and is more likely to affect structures at depths shallower than 50 feet. Liquefaction potential decreases as the fines (clay and silt) content of soil increases and liquefaction potential also increases as ground shaking increases.

We analyzed the liquefaction assuming the potential for a high groundwater table associated with the adjacent ditch. Based on the subsurface conditions encountered at the

Project site, we estimate less than a ¼‐inch of settlement at the north abutment and negligible settlement at the south abutment as a result of ground shaking during a 2‐percent probability of exceedance in a 50‐years or a 2,475‐year return period.

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103447-001 December 2019

5.1.5 Seismic Compression

Seismic compression typically occurs when loose, granular soil above the groundwater table rearranges into a tighter packing configuration during seismic shaking, which can cause settlement. The results of our analyses indicate there is low potential for seismic compression at the abutment locations.

5.2 Corrosion

Subgrade soils can be corrosive to substructure elements. To assist in estimating the corrosion potential at the site, samples were tested for pH, resistivity, water soluble sulfates, and chlorides. The results are presented in Table B‐1 in Appendix B.

The resistivity measured in the samples ranged from 1,350 to 2,061 ohm‐centimeters. Based on correlations developed by Roberge (2012), these values suggest a highly corrosive subsurface environment.

The concentration of water‐soluble sulfates measured in the samples was 0.001 to

0.002 percent by weight (1,000 to 2,000 parts per million). Based on classifications as defined by ACI‐318‐14 (ACI, 2014), these test results suggest a negligible degree of sulfate attack on concrete exposed to site soils (exposure class S0).

We recommend that a specialist in corrosion‐resistance design review the results included in

Table B‐1 to determine actual construction materials and methods based on the test results.

6 FOUNDATION RECOMMENDATIONS

As discussed in Section 2.0, we understand the proposed pedestrian bridge will consist of a prefabricated single span bridge founded on shallow foundations. In our opinion, shallow foundations are a cost‐effective and appropriate foundation system for the bridge abutments based on the subsurface conditions encountered at the site, provided the recommendations in this section are followed.

6.1 Seismic Design Criteria

Using the American Association of State Highway and Transportation Officials (AASHTO)

Load and Resistance Factor Design (LRFD) Bridge Design Specifications (AASHTO, 2017) criteria, and based on subsurface conditions encountered in our borings at the proposed pedestrian bridge (assuming that similar conditions are present from the maximum depth of

Geotechnical Design Report

103447-001 December 2019 our boring to a depth of 100 feet), Site Class D is recommended for the proposed bridge structure.

Ground motion parameters were determined for the project site using the USGS AASHTO

2009 Web Service Documentation Web Application (USGS, 2009) and procedures recommended by AASHTO (2017). Exhibit 6‐1 presents recommended seismic design ground motion parameters.

Exhibit 6-1: Seismic Design Ground Motion Parameters

Design Parameter Value Site Class D

Short-period Spectral Acceleration, SS 0.335 g

Long-period Spectral Acceleration, S1 0.163 g

Site Factor, FPGA 1.515

Site Factor, Fa 1.532

Site Factor, FV 2.148

Peak Design Spectral Acceleration, AS 0.216 g

Short-period Design Spectral Acceleration, SDS 0.513 g

Long-period Design Spectral Acceleration, SD1 0.350 g

TO 0.136 sec.

TS 0.682 sec.

g = gravity; sec. = seconds

6.2 Bearing Resistance

Shallow foundation load capacity is governed by the strength and settlement characteristics of the underlying soil strata. Our recommendations are based on LRFD criteria that were developed based on AASHTO LRFD Bridge Design Specifications (AASHTO, 2017).

Borings SW‐01 and SW‐02, which were completed at the north and south abutment, respectively, indicate that approximately 15 feet of sandy and clayey overburden overlie very dense sand and gravel at the abutment locations. Based on 95‐percent design plans provided by HDR (2019), we understand that foundation support at each abutment will consist of spread footings founded in the overburden clayey sands.

Based on discussions with HDR, we understand that the adjacent ditch may experience a rapid drawdown loading condition (wherein the ditch may be running full of water for a significant period of time, thereby saturating the adjacent ground, before “rapidly” emptying). We evaluated this case, which we considered an extreme limit state for the

Geotechnical Design Report

103447-001 December 2019 abutments. Given the proposed geometry we recommend that the abutments have a minimum foundation elevation of 113 feet to meet a minimum global stability factor of safety value of 1.1 for this loading condition.

Refer to Exhibit 6‐2 for required minimum foundation dimensions, estimated settlement values, and factored bearing resistance values.

Exhibit 6-2: Estimated Bearing Capacities

Location Abutment

Dimensions Estimated Settlement

Factored Bearing Resistance

Minimum Foundation Elevation

North Abutment 14 feet x 7 feet < 1 inch 2,500 psf 113 feet

South Abutment 12 feet x 7 feet < 1 inch 2,500 psf 113 feet psf = pounds per square foot

6.3 Lateral Earth Pressures

The lateral earth pressures on abutment and wing walls depend on many factors, including surcharge loads, the soil type, drainage provisions, and whether or not the top of the wall can yield or deflect laterally/rotate during and after excavation. Where walls are free to deflect, they can be designed for the active condition. Where a deflection greater than

0.001 times the height of the wall (0.001H) cannot occur, walls should be designed for at‐rest conditions. Active and at‐rest earth pressures provided in Exhibit 6‐3 assume the walls are backfilled with properly compacted onsite clayey sands or Structural Backfill in accordance with FP‐14 Section 704.04 in a 1 horizontal to 1 vertical (1H:1V) zone extending upward from the base of the wall from a point 1.5 feet behind the wall.

Exhibit 6-3: Recommended Lateral Earth Pressure Design Parameters

Design Parameter

Design Value On-site Clayey

Sand Fill Structural Backfill -

FP-14 Section 704.04

Total Unit Weight (pcf) 125 135

Effective Friction Angle (degrees) 28 34

Cohesion (psf) 0 0

Active Earth Pressure Coefficient, KA 0.36 0.28

Equivalent Fluid Density for Active Conditions (pcf) 45 40

At-Rest Earth Pressure Coefficient, KO 0.53 0.44

Equivalent Fluid Density for At-Rest Conditions (pcf) 65 60 pcf = pounds per cubic foot; psf = pounds per square foot

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103447-001 December 2019

The parameters provided in Exhibit 6‐3 assume a free‐draining backfill condition; refer to

Section 6.3.2 for wall drainage recommendations.

Surcharge loads from motor vehicles/traffic and construction equipment will induce additional lateral loads on walls. The pressures provided in Exhibit 6‐3 do not account for surcharge loads. Lateral loads due to various types of surcharges may be calculated by multiplying the surcharge by the active or at‐rest earth pressure coefficient (KA or KO). The earth pressure coefficients are also shown in Exhibit 6‐3. Surcharge loads should be applied as recommended on Figure 3.

6.3.1 Lateral Resistance

For structures founded on shallow foundations, lateral loads from wind, seismic, retained fill, and other loads may be resisted by frictional resistance along the base of the footing.

Passive pressure should be neglected in front of footings and walls due to the proximity to sloping ground. Our recommended lateral resistance parameters for design of abutment and wing walls are provided in Exhibit 6‐4.

Exhibit 6-4: Recommended Lateral Resistance Design Parameters

Design Parameter Value Nominal Coefficient of Friction for Sliding 1 0.40

Strength Limit Resistance Factor for Sliding 2 0.80

NOTES:

Value assumes cast-in-place concrete. If the concrete is precast, the provided value should be multiplied by a factor of 0.80.

Sliding resistance factor based on AASHTO (2017), Table 10.5.5.2.2-1.

Passive pressure should be ignored in front of walls.

6.3.2 Wall Drainage

The earth pressure parameters provided for the proposed retained fill assume a free‐ draining backfill condition. Based on plans provided by HDR (2019), the design high water elevation is within wall elements of the bridge. As such, it will be important to control surface water and to provide drainage measures that reduce the potential for water to accumulate behind walls, particularly considering the proximity of walls to the ditch channel.

Surface water behind the wall should not be allowed to discharge directly into the wall backfill materials. In addition, water should not be allowed to discharge or pond around retaining structures. We recommend sloping the ground surface in front of walls a minimum of 5 percent away from the wall face for a minimum horizontal distance of 10 feet

Geotechnical Design Report

103447-001 December 2019 measured from the face of the wall (or until a paved surface is encountered, whichever is less).

In general, materials with greater than about 3 percent fines content are not considered free draining. Assuming on‐site clayey sand fill or structural backfill is used, the backfill will not be free draining, and a rapid drawdown condition could occur following flood events, i.e., water could be trapped in the backfill after flood waters recede. This condition could be addressed by designing the wall for appropriate water pressures or by including internal drainage features to reduce the potential for water to accumulate in the backfill.

Appropriate drainage features could include:

Placement of a 12‐inch thick drainage layer on the back face of the wall, with a discharge system (e.g., weep holes or a perforated collector pipe at the base of the drainage layer, daylighting to a suitable discharge point).

Installation of geocomposite drainage boards on the back face of the wall, with a suitable discharge system (e.g., weep holes or a perforated collector pipe, daylighting to a suitable discharge point)

Limiting the fines content of the wall backfill to 3 percent.

7 CONSTRUCTION CONSIDERATIONS

The applicability of the design parameters in Section 6.0 is contingent on good construction practice. Poor construction techniques may alter conditions from those upon which our recommendations are based, and therefore result in poor performance. Our analyses assume that this project will be constructed according to FP‐14 U.S. Customary Units

(USDOT and FHWA, 2014) standards. The following sections provide additional construction considerations for this project.

7.1 Subgrade Preparation

All foundation subgrades (including areas requiring excavation) should be stripped, scarified to a depth of 6 inches, moisture conditioned, and compacted in place to a dense and unyielding condition per the requirements described in Section 204 and 208 of FP‐14

(2014). Where cohesionless subgrade soils are present, a 10‐ton (weight at drum, minimum) vibratory roller operating at a minimum of 1,000 vibrations per minute, or equivalent, should be used to compact the subgrade.

The compacted surface should be proof‐rolled with a fully loaded, tandem‐axle, 10‐yard dump truck or equivalent. Any areas that are identified as being loose, soft, or yielding

Geotechnical Design Report

103447-001 December 2019 during proof‐rolling should be removed, replaced, and compacted. Care should be taken during proof‐rolling and subgrade preparation to avoid disturbing subgrade soils and supporting soils that will remain in place, as they can rut and pump under repeated construction traffic.

7.2 Fill Placement

Fill materials should be placed in horizontal lifts, with the loose lift thickness not to exceed

6 inches. Thinner lifts may be required, depending on the contractor’s equipment.

Compaction of backfill adjacent to walls can result in higher lateral earth pressures against the walls. Therefore, small equipment that is hand‐operated should be required within a line extending upward from the base of the structure at 0.5H:1V, to a maximum horizontal distance of 5 feet from the face of the wall to reduce this potential.

All backfill materials should be moisture conditioned within 2 percentage points of the optimum moisture content and to at least 95 percent of the maximum dry density as determined by ASTM International (ASTM) D698 or AASHTO T99 (standard Proctor compaction effort). It should be noted that as the amount of fines (portion of soil particles passing a U.S. Standard No. 200 sieve) increases in the fill material, soil becomes more sensitive to small changes in moisture content, and adequate compaction becomes more difficult to achieve.

Exhibit 7‐1 summarizes our recommendations for fill and construction material selection.

All specification sections reference the FP‐14 U.S. Customary Units, (USDOT and FHWA, 2014).

Exhibit 7-1: Recommended Materials for Construction

Locations Specification Material Type Additional Requirements/Comments Abutment and

Wing Wall Backfill

FP-14 704.04 Structural Backfill Max. Particle Size: 3 inches Max. Fines Content: 15 percent Max. PI: 6

- On-Site Clayey Sand Fill Reuse onsite embankment material Max. Particle Size: 3 inches

Landscaping - Common Fill (on-site material)

No minimum requirements

Max. = Maximum; PI = Plasticity Index

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103447-001 December 2019

8 CLOSURE

This report has been prepared for the exclusive use of HDR and Central Federal Lands

Highway Division for the purpose of providing geotechnical recommendations for the pedestrian bridge at the Folsom South Trail Improvements project. This geotechnical design report should not be used without our approval if any of the following occurs:

Assumptions stated in this report have changed.

Project details change or new information becomes available such that our analyses and recommendations may be affected.

A substantial period of time has passed since the date of this report.

If any of these occur, we should be retained to review the applicability of our analyses and recommendations.

Within the limitations of scope, schedule and budget, the analyses, conclusions and recommendations presented in this report were prepared in accordance with generally accepted professional geotechnical and geological principles and practice in this area at the time this report was prepared. We make no other warranty, either express or implied.

Shannon & Wilson, Inc. has prepared “Important Information about Your Geotechnical

Report,” to assist you and others in understanding the use and limitations of our reports.

Geotechnical Design Report

103447-001 December 2019

9 REFERENCES

American Concrete Institute (ACI), 2014, Building code requirements for structural concrete and commentary, Farmington Hills, Mich., ACI 318‐14.

American Association of State Highway and Transportation Officials (AASHTO), 2017, AASHTO LRFD bridge design specifications, Customary U.S. units, 8th edition:

Washington, D.C., American Association of State Highway and Transportation

Officials.

Bryant, W.A., compiler, 2017, Fault number 506, Midland fault zone, in Quaternary fault and fold database of the United States: U.S. Geological Survey website, https://earthquakes.usgs.gov/hazards/qfaults, accessed 10/03/2019.

HDR, 2019, Preliminary 95% Plans, CA FTBR FSTR (2), Folsom South Trail Improvements

PH II, prepared for U.S. Department of the Interior Bureau of Reclamation.

Roberge, P.R., 2012, Handbook of corrosion engineering, Second Edition: McGraw‐Hill, New York, New York.

Strand, R.G., and Koenig, J.B., 1965, Geologic map of California: Sacramento sheet:

California Division of Mines and Geology, scale 1:250,000.

U.S. Department of Transportation (USDOT), Federal Highway Administration (FHWA), 2016, Design and Construction of Driven Pile Foundations. Publication No.

FHWA‐NHI‐16‐009. Available from:

https://www.fhwa.dot.gov/engineering/geotech/pubs/gec12/nhi16009_v1.pdf.

U.S. Department of Transportation (USDOT), Federal Highway Administration (FHWA), 2014, Federal standard specifications for construction of roads and bridges on

Federal Highway projects, FP‐14 English Units: U.S. Department of

Transportation and Federal Highway Administration.

U.S. Geological Survey (USGS) AASHTO 2009 Web Service Documentation Web

Application (USGS, 2009). Available from:

https://earthquake.usgs.gov/ws/designmaps/

Sacramento

CALIFORNIA

Project

Location

Los Angeles

San Francisco

VICINITY MAP

FIG. 1

Map adapted from aerial imagery provided by

Google Earth Pro, reproduced by permission granted by Google Earth ™ Mapping Service.

NOTE

Approximate Scale in Miles

1.5 3.0

December 2019 103447-001

F i l e n a m e

I E

F D

E N s

C

F L

C

A

F o l s o m

S

D r a f t i n g i g u r e d w g

D a t e o g i n m l w

MT

CA FTBR FSTR (2)

Folsom South Trail Improvements Sacramento County, California

PROJECT

LOCATION

G r a n t i

R a d

Florin Road

E x c e l s i o r

R o a d t

S c r a m e n t o to Clarksville to Rancho Cordova

S u n r i s e

B o u l e v a r d to Elk Grove

J a c k s d

SITE AND EXPLORATION PLAN

FIG. 2

Geotechnical and Environmental Consultants

SHANNON & WILSON, INC.

CA FTBR FSTR (2)

Folsom South Trail Improvements

Sacramento County, California

Approximate Scale in Feet

300 600

December 2019 103447-001

F i l e n a m e

I E

F D

E N s

C

C

F o l s o m

S

D r a f t i n g

F i g u r d t e g i n j c g

MT

Map adapted from aerial imagery provided by

Google Earth Pro, reproduced by permission granted by Google Earth ™ Mapping Service.

NOTE

Geotechnical Boring Designation and

Approximate Location

LEGEND

SW-01

SW-02

SW-01

S u n r i s e

B o u l e v a r d

J a c k s a d

Folsom South Canal Trail

Folsom South Canal

For m ≤ 0.4: H = 0.28 (psf) (see Note 3)

Fi le

: I :\E

F\ D

E N

\1

0s

\1

C

FL

C A

F ol so m

S \D el iv er ab le s\

Fi gu re s\

-0

_F ig

-T yp

S ur ch ar ge .d at e:

0-

-2 ut ho r:

jc g

W al l

PLAN VIEW

2.0

1.5

D ep th F ac to r, Z/

B

1.0

0.0

0.5

W al l

Z

Wall Line

UNIFORM SURCHARGE

EARTH BERM

(see Note 4)

Note:

H z=nH

Bottom of Excavation x = mH

Point Load in Pounds

H (psf)

ELEVATION VIEW

x = mH

H

Bottom of Excavation

W al l z=nH

H (psf)

Line Load in Pounds/Foot

B) LATERAL PRESSURE DUE TO LINE LOAD

i.e. NARROW CONTINUOUS FOOTING

PARALLEL TO WALL

C) LATERAL PRESSURE DUE TO STRIP LOAD

W al l

W al l

W al l

A) LATERAL PRESSURE DUE TO POINT LOAD

i.e. SMALL ISOLATED FOOTING OR WHEEL LOAD

D) LATERAL PRESSURE DUE TO EARTH BERM

OR UNIFORM SURCHARGE

Bottom of Excavation

Bottom of Excavation

E) LATERAL PRESSURE DUE

TO ADJACENT FOOTING

(see Notes 5 and 6)

0 0.5 1.0

L

B

NOTES

Figures are not drawn to scale.

Applicable surcharge pressures should be added to appropriate temporary and permanent wall lateral earth and water pressure.

If point or line loads are close to the back of the wall such that m 0.4, it may be more appropriate to model the actual load distribution (i.e., Detail E) or use more rigorous analysis methods.

See text for recommended K values.

The stress is estimated on the back of the wall at the center of the length, L, of loading.

The estimated stress is based on a Poisson's ratio of 0.5.

W al l

Bearing Pressure q (psf)

1.

2.

3.

4.

5.

6.

Ip, Influence Factor

H = 2(Ip) qs

Lateral Footing Pressure on Wall

(derived from NAVFAC DM 7.02, 1986; and Sandhu, Earth Pressure on Walls Due to Surcharge, 1974)

(derived from Poulos and Davis, Elastic Solutions for Soil and Rock Mechanics, 1974; and Terzaghi and

Peck, Soil Mechanics in Engineering Practice, 1967)

(NAVFAC DM 7.02, 1986)

(derived from Fang, Foundation Engineering Handbook, 1991)

(NAVFAC DM 7.2, 1986)

Point Load in Pounds

= Unit Weight of Earth Berm

Bearing Pressure

Earth Berm

H = Lateral Pressure in radians

ELEVATION VIEW

(see Note 3) (see Note 3) qs

L 2B

Qp

H2 n2

(0.16 + n2)3

For m > 0.4: H = 1.77 (psf) Qp

H2 m2n2

(m2 + n2)3

Qp

H

'H = H cos2 (1.1 ) (psf)

'H 'H

For m ≤ 0.4: H = 0.20 (psf) (see Note 3) Ql

H n

(0.16 + n2)2

For m > 0.4: H = 1.28 (psf) Ql

H m2n

(m2 + n2)2

QlQp

≤ 33° Hs ≤ 15 Feet

(K)( )(Hs) 2H

Hs

H = (K)qs (see Note 4) qs (psf)

H = ( - sin cos2 ) (psf)2q

L

= 0.25 = 0.5

= 1

H

L 2B

L 2B

L 2B

RECOMMENDED SURCHARGE

LOADING FOR TEMPORARY AND

PERMANENT WALLS

FIG. 3

CA FTBR FSTR (2)

Folsom South Trail Improvements

Sacramento County, California

103447-001December 2019

12/4/2019-103447-001_AA A-i

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A : S

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AC

E

EX

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OR

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Appen dix A: Subsurf ace Ex plorat ions

Appendix A

Subsurface Explorations

CONTENTS

A.1 Introduction ........................................................................................................................... A-1

A.2 Explorations ........................................................................................................................... A-1

A.2.1 Soil Classification System........................................................................................ A-1

A.2.2 Standard Penetration Test (SPT) ............................................................................ A-1

Figures Figure A-1: Soil Description and Log Key Figure A-2: Log of Boring SW-01 Figure A-3: Log of Boring SW-02

A-1

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A.1 INTRODUCTION

Shannon & Wilson, Inc.’s (Shannon & Wilson’s) field exploration program was conducted on August 5 and 6, 2019, and consisted of drilling two borings designated SW-01 and SW-02 at the locations shown on Figure 2. Photographs of boring locations are provided in Appendix C. The methods used to conduct the field exploration program are described below.

A.2 EXPLORATIONS

The borings were coordinated (including subcontractor coordination and utility locates) and observed by Shannon & Wilson. Individual boring logs are presented in Figure A-2 and A-3. These exploration logs represent our interpretation of the contents of the field logs and select results of laboratory testing. The borings were drilled by Cascade Drilling of Sacramento, California (under subcontract to Shannon & Wilson) using a truck-mounted CME 85 drill rig. The borings were advanced with 8-inch diameter hollow-stem augers to depths of approximately 75 feet. Groundwater was not encountered during drilling. On completion of drilling, the borings were backfilled with grout.

A.2.1 Soil Classification System

During exploration, our representative collected samples and prepared field logs of the explorations. Soil classification for this project was based on ASTM International (ASTM) Designation: D2487, Standard Practice for Classification of Soils for Engineering Purposes (Unified Soil Classification System), and ASTM Designation: D2488, Standard Practice for Description and Identification of Soils (Visual-Manual Procedure). The Unified Soil Classification System is summarized in Figure A-1. In addition, samples were classified based on American Association of State Highway and Transportation Officials (AASHTO) Designation M-145, Standard Specification for Classification of Soils and Soil-Aggregate Mixtures for Highway Construction Purposes.

A.2.2 Standard Penetration Test (SPT)

Disturbed samples were obtained in the borings in general accordance with the Standard Penetration Test (SPT) (ASTM Designation: D1586). The SPT consists of driving a 2-inch outside diameter (O.D.), 1.375-inch inside diameter split-spoon sampler a distance of 18 inches with a 140-pound hammer free-falling a distance of 30 inches. An automatic hammer system was used to advance the samplers. During sampling, the Shannon & Wilson field

A-2

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representative recorded the number of blows for each 6-inch increment of penetration and summed the blow counts for the last two 6-inch increments. This sum is recorded as the penetration resistance number, or N-value. If high penetration resistance prevented driving the total length of the sampler, the Shannon & Wilson field representative recorded the partial penetration depth and blow count. The N-values provide a means for evaluating the relative density or compactness of cohesionless (granular) soils and consistency or stiffness of cohesive (fine-grained) soils (see Figure A-1). The raw N-values are shown on the individual boring logs. Representative portions of the split-spoon sample obtained in conjunction with the SPT were placed in a screw-top plastic jar and transported to our laboratory.

December 2019 103447-001

Folsom South Trail Improvements

Sacramento County, California

1Gravel, sand, and fines estimated by mass. Other constituents, such as organics, cobbles, and boulders, estimated by volume.

2Reprinted, with permission, from ASTM D2488 - 09a Standard Practice for Description and Identification of Soils (Visual-Manual Procedure), copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428.

A copy of the complete standard may be obtained from ASTM International, www.astm.org.

140 pounds with a 30-inch free fall.

Rope on 6- to 10-inch-diam. cathead 2-1/4 rope turns, > 100 rpm

NOTE: If automatic hammers are used, blow counts shown on boring logs should be adjusted to account for efficiency of hammer.

10 to 30 inches long Shoe I.D. = 1.375 inches Barrel I.D. = 1.5 inches Barrel O.D. = 2 inches

Sum blow counts for second and third 6-inch increments.

Refusal: 50 blows for 6 inches or less; 10 blows for 0 inches.

RELATIVE

CONSISTENCY

N, SPT,

BLOWS/FT.

5% to 12% fine-grained:

with Silt or with Clay 3

15% or more of a second coarse-grained constituent:

with Sand or with Gravel 5

< 5%

5 to 10%

15 to 25%

30 to 45%

50 to 100%

Surface Cement Seal

Asphalt or Cap

Slough

Inclinometer or Non-perforated Casing

Vibrating Wire Piezometer

N, SPT,

BLOWS/FT.

< 4 4 - 10

10 - 30 30 - 50

> 50

DESCRIPTION

< #200 (0.075 mm = 0.003 in.)

#200 to #40 (0.075 to 0.4 mm; 0.003 to 0.02 in.)

#40 to #10 (0.4 to 2 mm; 0.02 to 0.08 in.)

#10 to #4 (2 to 4.75 mm; 0.08 to 0.187 in.)

SIEVE NUMBER AND/OR APPROXIMATE SIZE

#4 to 3/4 in. (4.75 to 19 mm; 0.187 to 0.75 in.)

3/4 to 3 in. (19 to 76 mm)

3 to 12 in. (76 to 305 mm)

> 12 in. (305 mm)

Fine Coarse

Fine Medium Coarse

BOULDERS

COBBLES

GRAVEL

FINES

SAND

Sheet 1 of 3

CONSTITUENT2

SOIL DESCRIPTION

AND LOG KEY

SHANNON & WILSON, INC.

Geotechnical and Environmental Consultants

Absence of moisture, dusty, dry to the touch

Damp but no visible water

Visible free water, from below water table

FIG. A-1

Shannon & Wilson, Inc. (S&W), uses a soil identification system modified from the Unified Soil Classification System (USCS). Elements of the USCS and other definitions are provided on this and the following pages. Soil descriptions are based on visual-manual procedures (ASTM D2488) and laboratory testing procedures (ASTM D2487), if performed.

STANDARD PENETRATION TEST (SPT)

SPECIFICATIONS

Hammer:

Sampler:

N-Value:

Dry

Moist

Wet

MOISTURE CONTENT TERMS

Modifying (Secondary)

Precedes major constituent

Major

Minor Follows major constituent

1All percentages are by weight of total specimen passing a 3-inch sieve.

2The order of terms is: Modifying Major with Minor.

3Determined based on behavior.

4Determined based on which constituent comprises a larger percentage.

5Whichever is the lesser constituent.

COARSE-GRAINED

SOILS

(less than 50% fines)1

NOTE: Penetration resistances (N-values) shown on boring logs are as recorded in the field and have not been corrected for hammer efficiency, overburden, or other factors.

PARTICLE SIZE DEFINITIONS

RELATIVE DENSITY / CONSISTENCY

Sand or Gravel 4

30% or more coarse-grained:

Sandy or Gravelly 4

More than 12% fine-grained:

Silty or Clayey 3

15% to 30% coarse-grained:

with Sand or with Gravel 4

30% or more total coarse-grained and lesser coarse-grained constituent is 15% or more:

with Sand or with Gravel 5

Very soft Soft Medium stiff Stiff Very stiff Hard

Very loose Loose Medium dense Dense Very dense

RELATIVE

DENSITY

FINE-GRAINED SOILS

(50% or more fines)1

COHESIVE SOILS

< 2 2 - 4 4 - 8

8 - 15 15 - 30

> 30

COHESIONLESS SOILS

Silt, Lean Clay, Elastic Silt, or

Fat Clay 3

PERCENTAGES TERMS 1, 2

Trace

Few

Little

Some

Mostly

WELL AND BACKFILL SYMBOLS

Bentonite Cement Grout

Bentonite Grout

Bentonite Chips

Silica Sand

Perforated or Screened Casing

S&W INORGANIC SOIL CONSTITUENT DEFINITIONS

S O

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2/

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Folsom South Trail Improvements

Sacramento County, California

GC

SC

Inorganic

Organic

(more than 50% of coarse fraction retained on No. 4 sieve)

MAJOR DIVISIONS GROUP/GRAPHIC

SYMBOL

CH

OH

ML

CL

TYPICAL IDENTIFICATIONS

Gravel

Sand

Silty Sand; Silty Sand with Gravel

Clayey Sand; Clayey Sand with Gravel

Clayey Gravel; Clayey Gravel with Sand

Sheet 2 of 3

Gravels

Primarily organic matter, dark in color, and organic odor

SW

(more than 12% fines)

Silts and Clays

Silts and Clays

(more than 50% retained on No.

200 sieve)

(50% or more of coarse fraction passes the No. 4 sieve)

(liquid limit less than 50)

(liquid limit 50 or more)

Organic

Inorganic

FINE-GRAINED

SOILS

SM

Sands

Silty or Clayey Gravel

Silt; Silt with Sand or Gravel; Sandy or Gravelly Silt

Organic Silt or Clay; Organic Silt or Clay with Sand or Gravel; Sandy or Gravelly Organic Silt or Clay

HIGHLY-

ORGANIC

SOILS

COARSE-

GRAINED

SOILS

OL

(less than 5% fines)

GW

Geotechnical and Environmental Consultants

SHANNON & WILSON, INC.

(less than 5% fines)

PT

FIG. A-1

(more than 12% fines)

MH

SP

GP

GM

Silty or Clayey Sand

Silty Gravel; Silty Gravel with Sand

(50% or more passes the No.

200 sieve)

SOIL DESCRIPTION

AND LOG KEY

Elastic Silt; Elastic Silt with Sand or Gravel; Sandy or Gravelly Elastic Silt

Fat Clay; Fat Clay with Sand or Gravel;

Sandy or Gravelly Fat Clay

Organic Silt or Clay; Organic Silt or Clay with Sand or Gravel; Sandy or Gravelly Organic Silt or Clay

Poorly Graded Sand; Poorly Graded Sand with Gravel

Well-Graded Sand; Well-Graded Sand with Gravel

Well-Graded Gravel; Well-Graded Gravel with Sand

Poorly Graded Gravel; Poorly Graded Gravel with Sand

Lean Clay; Lean Clay with Sand or Gravel; Sandy or Gravelly Lean Clay

Peat or other highly organic soils (see

ASTM D4427)

NOTES

1. Dual symbols (symbols separated by a hyphen, i.e., SP-SM, Sand with Silt) are used for soils with between 5% and 12% fines or when the liquid limit and plasticity index values plot in the CL-ML area of the plasticity chart. Graphics shown on the logs for these soil types are a combination of the two graphic symbols (e.g., SP and SM).

2. Borderline symbols (symbols separated by a slash, i.e., CL/ML, Lean Clay to Silt; SP-SM/SM, Sand with Silt to Silty Sand) indicate that the soil properties are close to the defining boundary between two groups.

S O

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9 NOTE: No. 4 size = 4.75 mm = 0.187 in.; No. 200 size = 0.075 mm = 0.003 in.

UNIFIED SOIL CLASSIFICATION SYSTEM (USCS)

(Modified From USACE Tech Memo 3-357, ASTM D2487, and ASTM D2488)

Folsom South Trail Improvements

Sacramento County, California

SHANNON & WILSON, INC.

Geotechnical and Environmental Consultants

FIG. A-1

Sheet 3 of 3

SOIL DESCRIPTION

AND LOG KEY

1Reprinted, with permission, from ASTM D2488 - 09a Standard Practice for Description and Identification of Soils (Visual-Manual Procedure), copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard may be obtained from ASTM International, www.astm.org.

2Adapted, with permission, from ASTM D2488 - 09a Standard Practice for Description and Identification of Soils (Visual-Manual Procedure), copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard may be obtained from ASTM International, www.astm.org.

Interbedded

Laminated

Fissured

Slickensided

Blocky

Lensed

Homogeneous

ATD

Diam.

Elev.

ft.

FeO gal.

Horiz.

HSA

I.D.

in.

lbs.

MgO mm

MnO

NA

NP

O.D.

OW

pcf

PID

PMT

ppm psi

PVC

rpm

SPT

USCS

qu

VWP

Vert.

WOH

WOR

Wt.

Crumbles or breaks with handling or slight finger pressure.

Crumbles or breaks with considerable finger pressure.

Will not crumble or break with finger pressure.

PLASTICITY2

CEMENTATION TERMS1

GRADATION TERMS

STRUCTURE TERMS1

ACRONYMS AND ABBREVIATIONS

Alternating layers of varying material or color with layers at least 1/4-inch thick;

singular: bed.

Alternating layers of varying material or color with layers less than 1/4-inch thick;

singular: lamination.

Breaks along definite planes or fractures with little resistance.

Fracture planes appear polished or glossy; sometimes striated.

Cohesive soil that can be broken down into small angular lumps that resist further breakdown.

Inclusion of small pockets of different soils, such as small lenses of sand scattered through a mass of clay.

Same color and appearance throughout.

Narrow range of grain sizes present or, within the range of grain sizes present, one or more sizes are missing (Gap Graded). Meets criteria in ASTM D2487, if tested.

Full range and even distribution of grain sizes present. Meets criteria in ASTM D2487, if tested.

Poorly Graded

Well-Graded

Weak

Moderate

Strong

Irregular patches of different colors.

Soil disturbance or mixing by plants or animals.

Nonsorted sediment; sand and gravel in silt and/or clay matrix.

Material brought to surface by drilling.

Material that caved from sides of borehole.

Disturbed texture, mix of strengths.

VISUAL-MANUAL CRITERIA

A 1/8-in. thread cannot be rolled at any water content.

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

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

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

Sharp edges and unpolished planar surfaces.

Similar to angular, but with rounded edges.

Nearly planar sides with well-rounded edges.

Smoothly curved sides with no edges.

Width/thickness ratio > 3.

Length/width ratio > 3.

PARTICLE ANGULARITY AND SHAPE TERMS1

ADDITIONAL TERMS

Angular

Subangular

Subrounded

Rounded

Flat

Elongated

DESCRIPTION

Nonplastic

Low

Medium

High

At Time of Drilling Diameter Elevation Feet Iron Oxide Gallons Horizontal Hollow Stem Auger Inside Diameter Inches Pounds Magnesium Oxide Millimeter Manganese Oxide Not Applicable or Not Available Nonplastic Outside Diameter Observation Well Pounds per Cubic Foot Photo-Ionization Detector Pressuremeter Test Parts per Million Pounds per Square Inch Polyvinyl Chloride Rotations per Minute Standard Penetration Test Unified Soil Classification System Unconfined Compressive Strength Vibrating Wire Piezometer Vertical Weight of Hammer Weight of Rods Weight

Mottled

Bioturbated

Diamict

Cuttings

Slough

Sheared

APPROX.

PLASITICITY

INDEX

RANGE

< 4

4 to 10

10 to 20

> 20

S O

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2/

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3.5 inches of asphalt over 3.5 inches of aggregate base course.

Loose to medium dense, red-yellow, Clayey Sand (SC); moist; trace gravel.

Very stiff, red-yellow, Sandy Lean Clay (CL);

moist.

Dense to very dense, red-yellow and brown, Silty Gravel with Sand (GM) to Poorly Graded Sand with Silt and Gravel (SP-SM); moist.

- Perched water at 45-feet.

D ur in g

D ril lin g

0.3

0.6

10.8

15.8

48.0

S -1

S -2

S -3

S -4

S -5

S -6

S -7

S -8

S -9

S -1

S

-1

S -1

SOIL DESCRIPTION

0 60

Total Depth:

Top Elevation:

Vert. Datum:

Horiz. Datum:

Ground Water Level ATD

Refer to the report text for a proper understanding of the subsurface materials and drilling methods. The stratification lines indicated below represent the approximate boundaries between material types, and the transition may be gradual.

Geotechnical and Environmental Consultants

103447-001

SHANNON & WILSON, INC.

Sheet 1 of 2

CONTINUED NEXT SHEET

S ym bo l

Hollow Stem Auger Cascade Drilling

CME 85

LEGEND

Drilling Method:

Drilling Company:

Drill Rig Equipment:

Other Comments:

Northing:

Easting:

Station:

Offset:

LOG OF BORING SW-01

December 2019

Sample Not Recovered

Hole Diam.:

Rod Type.:

Hammer Type:

G ro un d

W at er

D ep th , f t.

Standard Penetration Test

NOTES

76.5 ft.

WGS84

CA FTBR FSTR (2)

Folsom South Trail Improvements

Sacramento County, California

D ep th , f t.

20 40

FIG. A-2

S am pl es

8 in.

NWJ

Automatic

20 40 60

1. Refer to Figures A-1 and A-2 for explanation of symbols, codes, abbreviations and definitions.

2. The stratification lines represent the approximate boundaries between soil types, and the transition may be gradual.

3. The discussion in the text of this report is necessary for a proper understanding of the nature of the subsurface materials.

4. Groundwater level, if indicated above, is for the date specified and may vary.

5. USCS designation is based on visual-manual classification and selected lab testing.

QCL 2

M A

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Plastic Limit

(<0.075mm)

Liquid Limit Natural Water Content

% Fines % Water Content

140 lbs / 30 inches (blows/foot)PENETRATION RESISTANCE

Hammer Wt. & Drop:

50/3"

89/11.5"

50/6"

50/3"

50/6"

Very dense, red-yellow, Silty Gravel with Sand (GM); moist.

Hard, red-yellow, Lean Clay with Sand (CL);

moist.

Very stiff to hard, red-yellow, Elastic Silt (MH);

moist; trace sand.

Hard, red-yellow, Lean Clay (CL); moist; few sand.

BOTTOM OF BOREHOLE

COMPLETED ON 8/5/2019

53.0

58.0

73.0

76.5

S -1

S

-1

S -1

S

-1

S -1

S

-1

SOIL DESCRIPTION

0 60

Total Depth:

Top Elevation:

Vert. Datum:

Horiz. Datum:

Ground Water Level ATD

Refer to the report text for a proper understanding of the subsurface materials and drilling methods. The stratification lines indicated below represent the approximate boundaries between material types, and the transition may be gradual.

Geotechnical and Environmental Consultants

103447-001

SHANNON & WILSON, INC.

Sheet 2 of 2

S ym bo l

Hollow Stem Auger Cascade Drilling

CME 85

LEGEND

Drilling Method:

Drilling Company:

Drill Rig Equipment:

Other Comments:

Northing:

Easting:

Station:

Offset:

LOG OF BORING SW-01

December 2019

Sample Not Recovered

Hole Diam.:

Rod Type.:

Hammer Type:

G ro un d

W at er

D ep th , f t.

Standard Penetration Test

NOTES

76.5 ft.

WGS84

CA FTBR FSTR (2)

Folsom South Trail Improvements

Sacramento County, California

D ep th , f t.

20 40

FIG. A-2

S am pl es

8 in.

NWJ

Automatic

20 40 60

1. Refer to Figures A-1 and A-2 for explanation of symbols, codes, abbreviations and definitions.

2. The stratification lines represent the approximate boundaries between soil types, and the transition may be gradual.

3. The discussion in the text of this report is necessary for a proper understanding of the nature of the subsurface materials.

4. Groundwater level, if indicated above, is for the date specified and may vary.

5. USCS designation is based on visual-manual classification and selected lab testing.

QCL 2

M A

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2/

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Plastic Limit

(<0.075mm)

Liquid Limit Natural Water Content

% Fines % Water Content

140 lbs / 30 inches (blows/foot)PENETRATION RESISTANCE

Hammer Wt. & Drop:

50/2"

5.0 inches of asphalt over 6.0 inches of aggregate base course.

Loose to medium dense, red-yellow, Clayey Sand with Gravel (SC); moist.

Very stiff, red-yellow, Lean Clay (CL); moist;

trace sand.

Dense, red-yellow, Silt (ML); moist; few sand.

Stiff to very stiff, red-yellow, Sandy Lean Clay (CL); moist.

Medium dense, red-yellow, Sandy Silt (ML);

moist.

Very dense, red-yellow, Silty Gravel with Sand (GM); moist.

Very dense, red-brown, Poorly Graded Gravel with Sand and Silt (GP-GM); moist.

Very dense, red-yellow, Poorly Graded Sand with Gravel (SP); moist.

Very dense, brown, Poorly Graded Sand with Silt and Gravel (SP-SM); moist.

G ro un dw at er

N ot

E nc ou nt er ed

D ur in g

D ril lin g

0.4

0.9

7.0

9.5

12.0

14.5

18.0

28.0

33.0

38.0

48.0

S -1

S -2

S -3

S -4

S -5

S -6

S -7

S -8

S -9

S -1

S

-1

S -1

SOIL DESCRIPTION

0 60

Total Depth:

Top Elevation:

Vert. Datum:

Horiz. Datum:

Refer to the report text for a proper understanding of the subsurface materials and drilling methods. The stratification lines indicated below represent the approximate boundaries between material types, and the transition may be gradual.

Geotechnical and Environmental Consultants

103447-001

SHANNON & WILSON, INC.

Sheet 1 of 2

CONTINUED NEXT SHEET

S ym bo l

Hollow Stem Auger Cascade Drilling

CME 85

LEGEND

Drilling Method:

Drilling Company:

Drill Rig Equipment:

Other Comments:

Northing:

Easting:

Station:

Offset:

LOG OF BORING SW-02

December 2019

Sample Not Recovered

Hole Diam.:

Rod Type.:

Hammer Type:

G ro un d

W at er

D ep th , f t.

Standard Penetration Test

NOTES

76.5 ft.

WGS84

CA FTBR FSTR (2)

Folsom South Trail Improvements

Sacramento County, California

D ep th , f t.

20 40

FIG. A-3

S am pl es

8 in.

NWJ

Automatic

20 40 60

1. Refer to Figures A-1 and A-2 for explanation of symbols, codes, abbreviations and definitions.

2. The stratification lines represent the approximate boundaries between soil types, and the transition may be gradual.

3. The discussion in the text of this report is necessary for a proper understanding…