GEOTECHNICAL INVESTIGATION HEMET MOP LINE C, STAGE 4 STORM DRAIN WHITTIER AVENUE HEMET, CALIFORNIA

PREPARED FOR:

Attention: Joseph Caldwell, P.E. ALBERT A. WEBB ASSOCIATES 3788 McCray Street Riverside, California 92506

PREPARED BY:

INLAND FOUNDATION ENGINEERING, INC. 1310 South Santa Fe Avenue San Jacinto, California 92583

October 31, 2011 Project No. W175~068 INLAND FOUNDATION ENGINEERING, INC. Consulting Geotechnical Engineers 1310 South Santa Re Avenue San Jacinto, California 92583 (951) 654-1555 I I FAX (951) 654-0551

l October 31, 2011 Project No. W175-068

Attention: Joseph Caldwell, P.E. ALBERT A. WEBB ASSOCIATES 3788 McCray Street Riverside, California 92506

Re: Geotechnical Investigation Hemet MOP Line C, Stage 4 Storm Drain Whittier Avenue, Hemet, California

Dear Mr. Caldwell:

We are pleased to submit the results of our geotechnical investigation for the referenced project. This investigation was conducted in general accordance with our proposal dated January 5, 2011.

The results of our investigation indicate that the proposed storm drain project is feasible from a Geotechnical Engineering standpoint. Our report includes design recommendations along with the field and laboratory data.

We appreciate the opportunity of being of service to you on this project. If there are any questions, please contact our office.

Distribution: Addressee (4) TABLE OF CONTENTS

SCOPE OF SERVICES ...... 1

PROJECT DESCRIPTION ...... 3

GEOLOGIC SETTING ...... 4

SUBSURFACE CONDITIONS ...... 1 0

CONCLUSIONS AND RECOMMENDATIONS ...... 13 Overall Feasibility ...... 13 Expected Soil Types to Be Encountered ...... 13 Sand Equivalent Values and Soil Density ...... 14 Soil Compressibility, Preliminary Soil Strength ...... 14 Water Soluble Sulfates ...... 15 Rippability Concerns ...... 15 Trenching and Shoring Considerations ...... 15 Protection of Existing Facilities ...... 15 Allowable Bearing Pressure ...... 15 Lateral Earth Pressure ...... 16 Coefficient of Friction ...... 16 Unit Weight ...... 16 Pipe Design E' ...... 16 Settlement...... 16 Shrinkage and Subsidence ...... 16 Corrosivity ...... 17 Applicability/Feasibility of Jetting On-Site Materials ...... 17 Earthwork/Backfilling ...... 17

GENERAL ...... 19

REFERENCES ...... 20

APPENDICES

· APPENDIX A- Field Exploration ...... A-1 - A-13 Explanation of Logs ...... A-2 Exploratory Borings ...... A-3- A-12 Site Plan ...... A-13

APPENDIX B- Laboratory & Soil Mechanic's Testing ...... B-1- B-12 Analytical Testing ...... B-3 General ...... B-3 Maximum Density-Optimum Moisture Determinations ...... B-4 and B-5 Classification Testing ...... B-6 and B-7 Direct Shear Testing ...... B-8

1 TABLE OF CONTENTS

Consolidation Testing ...... B-9 through B-11 Expansion Testing ...... B-12

APPENDIX C- Closest Distances Between Site and Fault Ruptures ...... C-1

APPENDIX D- Soil Corrosivity Evaluation- HDR I SCHIFF ...... D-1

2 I. SCOPE OF SERVICES

This investigation was performed to determine engineering characteristics of the subsoil conditions and to develop recommendations for the design of a proposed storm drain. Our investigation included field exploration, laboratory testing, engineering analysis and the preparation of this report. Our investigation was performed in general accordance with our proposal dated January 5, 2011. The storm drain project is known as Riverside County Flood Control and Water Conservation District's Hemet MOP Line C, Stage 4 Storm Drain. The RCP storm drain will be located along Whittier Avenue from a point approximately 150 feet east of Palm Avenue to a point approximately 100 feet east of San Jacinto Street. Preliminary site plans prepared by Albert A. Webb Associates were used as a reference during this investigation.

Limitations: Our investigation was conducted for Albert A. Webb Associates and Riverside County Flood Control and Water Conservation District for their use in the design of the proposed storm drain. This report may only be used by Albert A. Webb Associates and Riverside County Flood Control and Water Conservation District for this purpose. The use of this report by parties or for other purposes is not authorized without written permission by Inland Foundation Engineering, Inc. Inland Foundation Engineering, Inc. will not be liable for any projects connected with the unauthorized use of this report.

Scope of Services: The purpose of the geotechnical investigation was to provide geotechnical parameters for design and construction of the proposed project. The scope of the geotechnical investigation included:

);:> A review of the general geologic conditions and specific subsurface conditions of the project site.

);:> An evaluation of the engineering and geologic data collected for the project.

);:> Preparation of a formal report providing geotechnical conclusions and recommendations for design and construction.

);:> The tasks performed in order to achieve these objectives included:

• The collection and review of data in order to develop an exploration program.

• Subsurface exploration to determine the nature and stratigraphy of the subsurface soils, and to obtain representative samples for laboratory testing.

Geotechnical Report- MDP Line C, Stage 4 Project No. W175-068- October 2011 1 Inland Foundation Engineering, Inc. • A visual reconnaissance of the site and surrounding area to ascertain the existence of any unstable or adverse geologic conditions.

• Laboratory testing of representative samples in order to establish the classification and engineering properties of the soils.

• Analysis of the data collected and the preparation of this report presenting our geotechnical conclusions and recommendations.

The information in this report represents professional opinions that have been developed using that degree of care and skill ordinarily exercised, under similar circumstances, by reputable geotechnical consultants practicing in this or similar localities. No other warranty, either expressed or implied, is made as to the professional advice included in this report.

Geotechnical Report~ MDP Line C, Stage 4 Project No. W/75-068 ~October 2011 2 Inland Foundation Engineering, Inc. II. PROJECT DESCRIPTION

The RCP storm drain will be located along Whittier Avenue from a point approximately 150 feet east of Palm Avenue to a point approximately 100 feet east of San Jacinto Street. The site is relatively planer and slopes to the west at an overall gradient of approximately one percent.

r 1

0 ... \ ~ ~ z ' l U.S.G.S. Topographic Map, Hemet 7.5' Quadrangle and Aerial Photograph (2009} Proposed Improvements: The storm drain project is known as a Riverside County Flood Control and Water Conservation District's Hemet MOP Line C, Stage 4 Storm Drain. The RCP storm drain will be located along Whittier Avenue from a point approximately 150 feet east of Palm Avenue to a point approximately 100 feet east of San Jacinto Street.

l The project under consideration consists of the construction of 6600 linear feet of underground storm drain. The new storm drain will have a diameter ranging from 60- . 1 inch to 72-inches and will be constructed of reinforced concrete pipe (RCP). The cover thickness of the storm drain will be approximately 12 to 15 feet.

Geotechnical Report - MDP Line C, Stage 4 Project No. W/75-068 - October 2011 3 Inland Foundation Engineering, Inc. Ill. GEOLOGIC SETTING

~ l Regional Geology: The subject site is situated within a natural geomorphic province in southwestern California known as the Peninsular Ranges, which is characterized by 11 steep, elongated ranges and valleys that trend northwesterly. This geomorphic province encompasses an area that extends 125 miles, from the Transverse Ranges and the Los Angeles Basin, south to the Mexican border, and beyond another 795 r 1 miles to the tip of Baja California (Norris & Webb, 1990; Harden, 1998). This province is believed to have begun as a thick accumulation of predominantly marine sedimentary and volcanic rocks during the late Paleozoic and early Mesozoic. Following this accumulation, in mid-Cretaceous time, the province underwent a pronounced episode of mountain building. The accumulated rocks were then complexly metamorphosed and intruded by igneous rocks, known locally as the Batholith. A period of erosion followed the mountain building, and during the late Cretaceous and Cenozoic time, sedimentary and subordinate volcanic rocks were deposited upon the [l eroded surfaces of the batholithic and pre-batholithic rocks. Following is a portion of C.D.M.G. Geologic Map of California, Santa Ana Sheet, (Scale 1 :250,000), Southern California (Rogers, 1965) depicting the approximate location of the project site:

l J

Geotechnical Report- MDP Line C, Stage 4 Project No. W175-068- October 2011 4 Inland Foundation Engineering, Inc. More specifically, the site is situated within the , an eroded mass of .I Cretaceous and older crystalline rock. Thin sedimentary and volcanic units mantle the bedrock in a few places with alluvial deposits filling in the lower valley areas. The Perris Block is a structurally stable, internally unfaulted mass of crustal rocks bounded [l on the west by the Elsinore-Chino fault zones, on the east by the San Jacinto fault zone, and on the north by the Cucamonga fault zone (Woodford, et al., 1971 ). On the south, the Perris Block is bounded by a series of sedimentary basins that lie between r 1 Temecula and Anza (Morton and Matti, 1989).

:I Local Geology: Based on geologic mapping by Morton & Matti (2005), the site is shown to be underlain by young alluvial fan deposits (Holocene and late Pleistocene - ,] Map Symbol Qyfb1) derived from Bautista Canyon. These materials are generally described as predominately gravel, sand, and silt.

r 1 Exploratory borings excavated by Inland Foundation Engineering, Inc. (July 2011) along the proposed alignment, indicate the site to be underlain by interbedded alluvial r 1 deposits including silty sands, clayey sands, sandy clays, sands, and silty clayey sands that are in a generally loose to medium dense condition, to a depth of at least 35.5-feet locally.

Following is a portion of the U.S.G.S. Preliminary Geologic Map of the Hemet 7.5' Quadrangle (Morton & Matti, 2004), depicting the mapped geologic units in the vicinity of the project site:

.]

Geotechnical Report - MDP Line C, Stage 4 Project No. WJ 75-068 - October 201 I 5 Inland Foundation Engineering, Inc. Young allu ial fan dcpo its of Bautista an on Unit I (Holocene Qyfb1 and late Plci tocene)-Unconsolidated deposits of all uvial fans and headward drainages of fans. Consists pr dominately of gravel, sand , and silt.

Groundwater: The subject site is located within the Hemet groundwater subbasin in southwestern Riverside County, California. This basin is adjacent to the Winchester groundwater subbasin and the Lakeview Mountains to the west, and the Santa Rosa ll Hills and Domenigoni Mountains to the south. The Casa Lama Fault (San Jacinto Valley Fault Segment) forms the eastern basin boundary and separates the relatively shallow Hemet subbasin from the much deeper San Jacinto groundwater subbasin. The Hemet subbasin is underlain by crystalline granitic and metamorphic bedrock at depth, with fill materials consisting of sand, silt, and clay eroded principally from the San Jacinto and Santa Rosa Mountains.

Groundwater was not encountered within any of our exploratory borings, which extended to depths of up to 35.5 feet. Based upon data prepared by the Western Municipal Water District Cooperative Well Monitoring Program (201 0), several wells in the vicinity of the project have been monitored recently. State Well No. 5S1W16J001S, located approximately % mile southwest of the westerly portion of the alignment, was monitored on February 25, 2010. At that time, the depth to groundwater was 256.8 feet beneath the existing ground surface. State Well No. 5S1W14P001S, located approximately% mile south of the easterly portion of the alignment was monitored on January 1, 2010. At that time, the depth to groundwater was 286 feet.

Faulting: There are at least 41 major late Quaternary active/potentially active faults that are within a 1GO-kilometer radius of the site as tabulated within Appendix C. Of these, there are no faults known to traverse the site, based on published literature, nor was there any photogeologic or surficial geomorphic evidence suggestive of faulting. In addition, the site in not located within a State of California "Alquist-Priolo Earthquake Fault Zone" for fault rupture hazard (Hart and Bryant, 1997). The nearest know active fault is the Casa Lama Fault (southern branch of the San Jacinto Zone locally), approximately 1.13 miles to the northeast of the easterly end of the alignment (C.D.M.G., 1980a), referred hereafter as the San Jacinto Fault. The San Jacinto Fault (San Jacinto Valley Segment, C. D. M.G., 1996) is a right-lateral, strike slip fault, being approximately 42 kilometers in length, with an estimated maximum magnitude (Mw) earthquake on Mw 6.9 and an associated slip-rate of 12.0 ±6.0 mm/year.

According to maps compiled by the California Department of Conservation, Division of Mines and Geology (CDMG) the major faults influencing the site, distances and maximum earthquake magnitudes are as follows:

Geotechnical Report- MDP Line C, Stage 4 Project No. W175-068- October 2011 6 Inland Foundation Engineering, Inc. l EARTHQUAKE DISTANCE MAGNITUDE SLIP RATE r 1 FAULT ZONE (Km) (Mw) (mm/yr) San Jacinto-San Jacinto Valley 1.8 6.9 12.00 [l San Jacinto-Anza 2.0 7.2 12.00 San Andreas - Southern 30 .8 7.4 24.00 Elsinore-Temecula 32.4 6.8 5.00 'l Elsinore-Glen Ivy 37.5 6.8 5.00 Following are combined portions of Earthquake Fault Zone Maps (San Jacinto and 1 Hemet Quadrangles) indicating the site is not located within a State of California "Alquist-Priolo Earthquake Fault Zone" for fault rupture hazard. f 1

( l

Ref: "Digital Images of Official Maps of Alquist-Priolo Earthquake Fault Zones of California, Southern Region" DMG CD 2000-003

l l In addition, current mapping by the Riverside County Land Information System indicates that the site does not lie within a mapped County fault zone.

Our review for this project has included an examination of one non-stereo and nine stereo pairs of vertical black and white aerial photographs dating between the years of 1962 and 2010 (see References for a listing) to aid in assessing the geologic and

Geotechnical Report - MDP Line C, Stage 4 Project No. W175-068- October 2011 7 Inland Foundation Engineering, Inc. geomorphic characteristics with respect to the site and vicinity. The photogeologic analysis did not reveal observed indicators suggestive of active fault-related features along the proposed alignment. This included the lack of photolineations and/or no consistent tonal variations observed across the project alignment.

Our site reconnaissance did not reveal any geomorphic, vegetative, or other indicators suggestive of active faulting across the project alignment. In addition, the subsurface boring log data did not suggest any obvious or suspected presence of faulting at the site. The site is not located within a designated Alquist-Priolo Earthquake Fault Zone for fault rupture hazards. Ground rupture is generally considered most likely to occur along pre-existing faults. Based on our review of published geologic maps, aerial photograph review, and site reconnaissance, it is our opinion that the potential for ground rupture at the site is considered to be low.

Seismicity: On the bases of the subsurface conditions and local fault characteristics, the 2010 California Building Code provides the following seismic design parameters as indicated in the following table:

Table 1613.5.2 Site Class D Fig. 1613.5.3 Mapped Spectral Acceleration - Ss 1.779g Fig. 1613.3 Mapped Spectral Acceleration - S1 0.720g Table 1613.5.3 (1) Site Coefficient- Fa 1.0 Table 1613.5.3 (2) Site Coefficient - Fv 1.5 Eq. 16-36 MCE Spectral Acceleration - SMs 1.779g Eq. 16-37 MCE Spectral Acceleration - SM1 1.080g Eq. 16-38 Design Spectral Acceleration - Sos 1.186g Eq. 16-39 Design Spectral Acceleration - So1 0.720g

It is recommended that all structures be designed to at least meet the current California Building Code (CBC) provisions in the latest CBC edition; however, it should be noted that the building code is intended as a minimum design condition and is often the maximum level to which structures are designed. Structures that are built to minimum code are designed to remain standing after an earthquake in order for occupants to safely evacuate, but then may have to ultimately be demolished (Larson and Slosson, 1992).

Geotechnical Report- MDP Line C, Stage 4 Project No. W175-068- October 2011 8 Inland Foundation Engineering, Inc. It is the responsibility of both the property owner and project structural engineer to determine the risk factors with respect to using CBC minimum design values for the subject project. The previously-outlined CBC seismic classifications and data have been provided for use by the project structural engineer, to aid in evaluating design cri­ teria, if needed. This information should be used to help select the appropriate seismic parameters, as outlined in the California Building Code (CBC, 201 0).

The primary geologic hazard affecting the project is that of ground shaking. Other secondary effects and geologic hazards include slope failure, lurching, seismic settlement, seiches, tsunamis, and surface rupture. These are not considered to be of significance to the project.

Liquefaction: The depth to groundwater beneath the site is in excess of 50 feet beneath the surface. Therefore, the potential for liquefaction is considered nil.

Geotechnical Report- MDP Line C, Stage 4 Project No. WJ75-068- October 2011 9 Inland Foundation Engineering, Inc. IV. SUBSURFACE CONDITIONS

Our field investigation consisted of drilling 10 exploratory borings to maximum depths of approximately 35.5 feet. The borings were excavated by means of a truck mounted rotary auger drill rig at the approximate locations shown on Figure No. A-13. A description of our drilling and sampling procedures and the Boring Logs are presented in Appendix A. Laboratory testing was performed on selected samples of the subsurface soils. Results of these tests are presented in Appendix B.

In addition to subsurface exploration, a review of the Soil Survey of Western Riverside Area, California was made. This review reveals that there are several mapped agricultural soil units present along the project alignment. These include (from west to east) San Emigdio Fine Sandy Loam (SeA), San Emigdio Loam (SgA), San Emigdio Fine Sandy Loam, deep (SfA), Metz Loamy Fine Sand (MdC), and Metz Loamy Fine Sand, Sandy Loam Substratum (MhB). Soil type classifications are useful tools in identifying particular site conditions that may be present along the alignment. The mapped soil series along the alignment are described as:

San Emigdio Series (SeA, SgA, SfA)- These are well-drained soils on alluvial fans developed in alluvium from weakly consolidated sedimentary formations. In a typical profile, the surface layer is light brownish gray fine sandy loam about 8 inches thick. The next layer, of similar color and texture, is about 14 inches thick. Underlying this and extending to a depth of more than 60 inches is light gray fine sandy loam.

These soils typically contain more than 50 percent fines passing No. 200 Sieve, (except unit SfA, which is 15 to 20 percent fines), have slight to medium compressibility, poor to fair stability, and poor resistance to piping.

Metz Series (MdC. MhB) - This soil series consists of somewhat excessively drained soils that occur on alluvial fans. These soils developed in alluvium from weakly calcareous sandstone and shale. In a typical profile, the upper 18 inches is light brownish-gray loamy fine sand. Below this is light brownish-gray loamy coarse sand and light-gray sand.

These soils typically contain 5 to 35 percent fines (passing No. 200 Sieve), have slight compressibility, fair stability, and poor resistance to piping.

Geotechnical Report- MDP Line C, Stage 4 Project No. W175-068- October 2011 10 Inland Foundation Engineering, Inc. ~ I 11 l ]

The results of our subsurface exploration revealed conditions that appear to be fairly consistent with those indicated by the Soil Survey for the surficial materials.

A typical profile of the conditions revealed by our exploration along the project align­ ment is presented in the following cross-section:

u5 .8 c: '(3 u5 ro Q) ..., c: lL ro u5 (f) .sc: ~ ro 5 (f) ro ' c: i Q) i ::::l B-08 ! u5 a:J 2 !· ... . (f).s u5 B- I t i Q) j . ·. ; 1 .0 1;· 0 B-0 . . . . 1,590 I : ...... I I . . : 1,580

1,570

l I 1,560

...... 1,550

500 1,000 1,500 2.000 2,500 3,000 3,500 4.000 4,500 5,000 5,500 6.000

LEGEND I?Zl CLAYEY SAND Oil SILTY SAND Ed SAND with SILT ~ SANDY CLAY [I!] SANDY SILT

Geotechnical Report- MDP Line C, Stage 4 Project No. WI 75-068- October 2011 11 Inland Foundation Engineering, Inc. The results of our investigation indicate that the site may be characterized as being underlain by alluvial materials consisting of interbedded silty sands, clayey sands, sandy clays, sands, and silty clayey sands that are in a generally loose to medium dense condition, to a depth of at least 35.5-feet locally. The Sand Equivalent values ranged from approximately 10 to 32.

The moisture content of the soil at the time of our investigation ranged from approximately 3 to 23 percent. A detailed description of the subsurface soil conditions encountered is presented on the attached Boring Logs, Figure Nos. A-3 through A-12. The soil is in a medium dense to dense condition with Relative Compactions ranging from approximately 70 to 90 percent. Consolidation testing indicates the soil is only slightly compressible. The soil is over-consolidated and does not appear to be collapsible.

Analytical testing indicates concentrations of water-soluble sulfates of less than 0.001 to 0.02 percent. Chloride concentrations ranged from approximately 60 to 255 parts per million. The pH values ranged from 7.2 to 8.1. Saturated Resistivities ranged from 1482 to 6864 ohm-em. HDR I Schiff Associates conducted additional corrosion testing and prepared a Corrosivity Evaluation for this project, which is appended.

Each of our borings was drilled through existing pavement. Pavement sections consisted of Asphalt Concrete (AC) placed over native soils and AC placed over Decomposed Granite (DG). Where AC was placed over native soils, thicknesses ranged from 6.5 to 9.5 inches. Where AC was placed over DG, AC thicknesses ranged from 4. 75 to 8.5 inches. The thickness of the DG ranged from 3.5 to 6.5 inches.

Groundwater was not encountered in our exploratory borings to a depth of at least 35.5 feet.

Geotechnical Report- MDP Line C, Stage 4 Project No. W175-068- October 2011 12 Inland Foundation Engineering, Inc. V. CONCLUSIONS AND RECOMMENDATIONS

Geotechnical design and construction considerations for this project are discussed below. These considerations include:

•!• Overall feasibility •!• Soil types expected to be encountered/geologic logs •!• Excavation characteristics •!• Suitability of on-site materials as related to applicability/feasibility of jetting /-{•!•1 Description of groundwater, site and subsurface conditions I // · •!• Recommendations for unusual soil conditions or groundwater conditions during \ construction, if encountered •!• Soil compressibility, preliminary soil strength •!• Soluble sulfate analysis •!• Trenching and shoring considerations

Specific design parameters presented for the pipe,~nd structure installation include: )

•!• Allowable bearing pressure •!• Design lateral earth pressures •!• Shoring/trench safety •!• Coefficient of friction •!• Sand Equivalent values and soil density •!• Site Preparation including compaction requirements and compaction characteristics of native soils •!• Shrinkage and subsidence •!• Corrosion protection recommendations •!• General site grading/backfilling recommendations

Overall Feasibility: Based on our investigation, the project appears to be feasible from a geotechnical and geologic standpoint, provided our conclusions and recommendations for this project are considered. The soils are granular and in a medium dense to dense condition. Some clean sands were encountered and may be susceptible to caving. The layers of silt will enhance the overall stability. Groundwater was not encountered and is not expected to be of significant concern during construction.

Expected Soil Types To Be Encountered: The surface and subsurface materials that will be encountered during the construction of this project will include predominately granular materials. In general, the materials encountered within our

Geotechnical Report- MDP Line C, Stage 4 Project No. W175-068- October 2011 13 Inland Foundation Engineering, Inc. exploratory borings consist of silty sand and sand interbedded with layers of silt. Sand Equivalent values ranged from 10 to 32. Generally, the cleaner more granular materials occur at depth.

Sand Equivalent Values and Soil Density: The density of the in-place materials was determined using the relatively undisturbed samples retrieved during the field exploration. Unit weights within the planned excavation depths were observed to be variable and ranged from approximately 90 to 115 pounds per cubic foot.

Sand Equivalent values ranged from 10 to 32. The following table presents the Sand Equivalent values on representative samples along the alignment:

B-01 3.75-11.5 10 B-02 13.0-17.0 10 B-03 4.5-9.0 26 B-05 5.0-9.5 22 B-07 0.65-4.0 32 B-09 5.0-9.5 11 B-09 13.75-21.0 26 B-10 4.0-9.5 10

Soil Compressibility, Preliminary Soil Strength: Consolidation testing indicates that the alluvial soils are only slightly compressible. There is no evidence that the soil is collapsible.

Although our testing indicates that the soil is predominantly granular, layers of fine­ grained soil were observed in the field. These were unavoidably blended in bulk soil samples used for classification testing. Testing indicated the presence of expansive soils along the project alignment. Expansion Indices ranged from approximately 8 to 30.

Direct shear testing was conducted upon samples remolded to the in-place densities and undisturbed specimens. The angle of internal friction from the testing ranged from 24 to 334 degrees. The lower friction angles occurred in the fine-grained soils that were not reflected in the classification testing of bulk soil samples. Cohesive strengths were minimal.

The native soils should be suitable for pipe bedding depending upon the pipe design.

Geotechnical Report- MDP Line C, Stage 4 Project No. W175-068- October 2011 14 Inland Foundation Engineering, Inc. Water Soluble Sulfates: Testing indicates that the soil has low concentrations of water-soluble sulfates. This is addressed in the report of the Soil Corrosivity Evaluation, which is appended.

Rippability Concerns: The soils are typically younger alluvial deposits with minor cementation. Our investigation did not reveal materials expected to cause excavation difficulties for conventional equipment. Some caving in the cleaner soil deposits should be anticipated. However, our boring logs indicate that these deposits may not be encountered within the excavations depths.

Trenching and Shoring Considerations: All trenches shall be configured and shored in accordance with the requirements of CaiOSHA. We would classify the soils as Type C. Some cohesionless soils may be encountered at depth that may be subject to caving when exposed in unshored vertical excavation sidewalls. The contractor should have a "competent person" on-site for the purpose of assuring safety within and about all construction excavations. Excavations shall have a maximum slope of 1.5:1 (H:V) and shall not exceed eighteen (18) feet in height. Shoring, shields, or other protective systems shall be used in accordance with all specifications, recommendations, and limitations provided by the manufacturer. Shoring should be designed using an at-rest earth pressure of 80 pounds per cubic foot. We have assumed a Unit weight of compacted backfill to be 134 pounds per cubic foot for this determination. This is based upon compacted soil at near optimum moisture content. A Registered Professional Engineer shall design sloping or benching for excavations greater than twenty feet deep.

Protection of Existing Facilities: Where existing utilities cross or are exposed by the planned excavation, we recommend that these lines be assessed for sensitivity to post-construction settlements. Typically, this is a concern for rigid pipelines such as water and sewer lines. In these cases, we recommend that the placement of com­ pacted backfill be terminated no closer than 12 inches from the line. At that point, the backfill should consist of a sand-cement slurry (one-sack) or Controlled Low Strength Material (CLSM) placed to at-least the spring line of the pipe. This will assure adequate post-construction support and will minimize the effects of the overlying backfill.

Allowable Bearing Pressure: We are not currently aware of foundation configurations for any of the proposed structures. We do not anticipate any deficiencies requiring recompaction of soils supporting structures. A conservative design value for any proposed foundations would be tO"QQ"p<:)U!l9~ Q~I §qhJ9re foot assuming foundation supported upon undisturbed soil having an in-place Relative

Geotechnical Report- MDP Line C, Stage 4 Project No. W/75-068- October 2011 15 Inland Foundation Engineering, Inc. Compaction of at least 85 percent or soil that is recompacted to at least 90 percent Relative Compaction.

Lateral Earth Pressure: Lateral earth pressure will act on buried walls of the pro­ posed inlet structures and other appurtenances. Cantilever walls supporting compacted fill soils should be designed using an equivalent active earth pressure of 54 pounds per cubic foot (pcf) for level backfill. Braced walls should be designed for at­ rest earth pressure of 80 _pGf.

Design lateral loads may be resisted by passive earth pressure on foundations on compacted fill or dense native soils. This resistance may be determined from a design passive pressure based on an equivalentfi1Jid pressure of 175 pcf. This value includes -....y."-"'"-·"" •• - -~---··~- ~-··- w--~v·"•·o~-~.w.~~,.~~o~-.~:''"''. .;/CO";'-x;!,c .. ,, a factor of safety of 1.5 on the ultimate passive pressure.

Appropriate drainage should be provided behind the walls to prevent the build-up of hydrostatic pressures. All subdrain systems must be protected against piping by means of graded filters or filter fabrics.

Coefficient Of Friction: A coefficient of friction of 0.29 between soil and concrete may be used with dead load forces only.

Unit Weight: Our recommendations are based upon a total unit weight of 134 pounds per cubic foot for compacted backfill.

Pipe Design E': Values of the Lateral Modulus of Subgrade Reaction (E') may vary across the alignment. Based upon the material types anticipated, we recommend a Lateral Modulus of Subgrade Reaction not exceeding 400 pounds per cubic inch.

Settlement: Settlements under foundations for the proposed structures are expected to be minor. Considering a continuous load of 2 kips per linear foot at a depth of 4 feet and a bearing pressure not exceeding 1 kip per square foot, settlements are expected to be on the order of one-half inch.

Shrinkage and Subsidence: Volumetric shrinkage of surficial soils that are excavated and replaced as controlled compacted fill will be minimal. We estimate that this shrinkage will be less than ten percent. Subsidence of soil surfaces that are scarified and compacted will be on the order of 0.1 feet per foot of recompaction. The effects of the recompaction of the soil "in-place" may extend up to two feet beneath the surface that is compacted. Therefore, subsidence due to such recompaction may be

Geotechnical Report- MDP Line C, Stage 4 Project No. WJ75-068- October 2011 16 Inland Foundation Engineering, Inc. up to 0.2 feet. Subsidence due to compaction will vary depending upon the type of equipment used and the moisture content of the soil at the time of grading. tl Corrosivity: A corrosivity evaluation for this project was conducted by HDR I Schiff n Associates. The report indicates that the ~oils are classified as severely corrosive to ferrous metals, aggressive to copper, and aggressive with ~s pect to exposure of reinforcing steel to the migration of chloride. Recommendations for corrosion [l protection of the storm drain are presented in the Corrosion Evaluation report, which is appended. The primary factors in the development of these recommendations appear r 1 to be related to Low Saturated Resistivities and high Chloride contents.

Applicability/Feasibility of Jetting On-Site Materials: On-site soils are not compatible to compaction by jetting. The use of sand/cement slurry or Controlled Density Fill (CDF) may be an acceptable alternative.

Earthwork/Backfilling: The on-site materials are suitable for use as compacted backfill. Soils should be brought to near optimum moisture content and compacted in 6 to 8 inch thick loose lifts to a ml,!mum of 90 percent of the maximum dry density as determined by Caltrans test m[~~od 216 or ASTM Standard D1557-09, whichever is indicated in the project specifications. Soils should be mechanically compacted. Compaction of native soil by jetting is not recommended. Jetting of imported backfill may be feasible provided that th-e soil has less than 10% particles finer than the #200 Sieve and a Sand Equivalent of at least 30. Jetted backfill should still be subject to compliance with compaction specifications. The decision to utilize compaction by jetting of approved material will be the responsibility of the contractor who will assume all associated risks. All work shall be in accordance with District requirements. The following specifications have been developed on the basis of our field and laboratory testing:

Trench Backfill: Trench backfill material should be native or approved granular materials which are free of organic and deleterious materials, rocks or lumps greater than 3 inches in greatest dimension and other unsuitable materials. Trench backfill may be compacted at near optimum moisture content by mechanical means as necessary for the achievement of satisfactory compaction. Unless otherwise specified by the drawings, specifications or encroachment permits, the minimum acceptable degree of compaction shall be 90 percent of I the maximum dry density. This is with the exception of the upper 12 inches within roadway areas which shall be compacted to a minimum of 95 percent j Relative Compaction.

Geotechnical Report - MDP Line C. Stage 4 Project No. W175-068- October 2011 17 Inland Foundation Engineering, Inc. Import Materials: All proposed import soils should be reviewed by the soils engineering consultant prior to use. It is anticipated that only on-site soils will be used for this project. Expansive soils should not be imported for this project. At least two working days notice should be allowed for the soil engineer to review and approve any proposed imported soils. If laboratory testing is necessary to obtain approval of import soils, an additional one to two days should be allowed. To provide protection from particle migration, imported pipe embedment material should be in accordance with the following criteria:

D15 > 0.1 mm, and D5o <3. 75 mm,

where D15 and D5o represent bedding material particle sizes corresponding to 15 and 50 percent passing by weight, respectively. Washed Concrete Sand will meet these criteria.

Observations and Compaction Testing: During backfilling, observations and compaction testing shall be conducted in order to verify satisfactory compaction. The Maximum Dry Density-Optimum Moisture Content relationship shall be determined by means of either the ASTM Standard D1557-09 test method of California Test Method No. 216, whichever is indicated in the project specifications. The field density shall be determined by either the ASTM Standard D1556-07 (Sand Cone) or ASTM 6938-08a (Nuclear) test method. The compaction shall be verified at maximum intervals of 250 feet for each 2-foot vertical'lift or as otherwise determined to be necessary by the inspector in the field during backfilling. Some backfill and compaction methodologies will dictate much shorter test intervals.

Retests: Should testing reveal insufficient compaction, additional testing may be necessary in order to define the area requiring recompaction. Without further testing, it should be assumed that the area between a failing test and a passing test is not properly compacted. As a guideline for evaluation, one test may be taken at a distance from the failing test equal to 20 percent of the distance to the next passing test. If the test reveals satisfactory compaction, the area between the failing test and the passing test shall be recompacted. If the test reveals inadequate compaction, the process should be repeated in order to delineate the unsatisfactory area. After recompaction of "failing" areas, retesting should be conducted in order to confirm satisfactory compaction. At least one retest is required for each failing test, even if failing tests are for the purpose of delineating the area requiring additional work.

Geotechnical Report- MDP Line C, Stage 4 Project No. Wl75-068- October 2011 18 Inland Foundation Engineering, Inc. VI. GENERAL

The findings and recommendations presented in this report are based upon an interpolation of the soil conditions between boring locations. Due to the type of exploration and the limited soil exposures resulting from exploratory borings, the boring logs may not present a thorough characterization of the actual subsurface conditions. Conditions should be anticipated to vary between boring locations. Significant changes may require revisions in the recommendations presented herein. Should conditions be encountered during construction that appear to be different than those indicated by this report, this office should be notified. We recommend that a pre-job conference be held on the site prior to the initiation of construction. The purpose of this meeting will be to assure a complete understanding of the recommendations presented in this report as they apply to the actual work to be performed.

Geotechnical Report- MDP Line C, Stage 4 Project No. W175-068 October 2011 19 Inland Foundation Engineering, Inc. REFERENCES

ASCE/SEI, 2006, ASCE Standard 7-05, Minimum Design Loads for Buildings and Other Structures.

Blake, T.F. 1989-2000a, EQSEARCH, A Computer Program for the Estimation of Peak Horizontal Acceleration from Southern California Historical Earthquake Catalog, Version 3.00b.

Blake, T.F. 1998-2000, UBCSEIS, A Computer Program for the Estimation of Uniform Building Code Coefficients Using 3-D Fault Sources, Version 1.03.

Blake, T.F. 1988-2000, FRISKSP, A Computer Program to Perform Probabilistic Earthquake Hazard Analysis Using Multiple Forms of Ground-Motion-Attenuation Relationships, Version 4.0.

California Division of Mines and Geology (C.D.M.G.), 1980 Hemet Quadrangle Earthquake Fault Zone 7-1/2' Quadrangle, Scale 1" =2,000'.

California Division of Mines and Geology (C.D.M.G.), 1980 San Jacinto Quadrangle Earthquake Fault Zone 7-1/2' Quadrangle, Scale 1" = 2,000'.

California Division of Mines & Geology (C.D.M.G.), 1986, "Guidelines to Geologic/Seismic Reports," Note No. 42.

California Division of Mines & Geology (C.D.M.G.), 1997, Guidelines for Evaluating and Mitigating Seismic Hazards in California, CDMG Special Publication 117.

Castellanos, Edward, 2005, EQLIQUE and SETTLE "2", Applied Geotech. Coduto, Donald, 2001, Foundation Design: Principles and Practice, Second Edition, Prentice Hall.

Hart, E.W. and Bryant W., 1997, "Fault Rupture Hazard Zones in California," California Division of Mines & Geology Special Publication 42.

Jennings, C.W., 1992, Preliminary Fault Activity Map of California, Scale 1:750,000, C.D.M.G. Open File Report 92-03.

Morton, D.M., and Matti, J.C., 2005, Preliminary Geologic Map of the Hemet 7.5' Quadrangle. U.S.G.S. Open File Report 04-1455.

Riverside County Flood Control and Water Conservation District, Topographic Maps, Sections 14 and 15, T.5 S., R. 1 W., SBB&M., Scale 1:2400.

Riverside County Land Information System GIS Maps, 2011.

Geotechnical Report- MDP Line C, Stage 4 Project No. W175-068- October 2011 20 Inland Foundation Engineering, Inc. Rodgers, T.H., 1966, Geologic Map of California, Santa Ana Sheet, Scale 1:250,000 (Second Printing 1973).

Western Municipal Water District Cooperative Well Monitoring Program (2010)

AERIAL PHOTOGRAPHS UTILIZED

Riverside County Flood Control District, 1962, Photo Nos. 2-236 and 2-237, Scale 1 II = 2,000', January 29, 1962.

Riverside County Flood Control District, 1974, Photo Nos. 527 and 528, Scale 111 =2,000', June 24, 1974.

Riverside County Flood Control District, 1980, Photo Nos. 559 and 560, Scale 1II= 2,000', April18, 1980.

Riverside County Flood Control District, 1984, Photo Nos. 970-972, Scale 1 II = 1 ,600', January 20, 1984.

Riverside County Flood Control District, 1990, Photo Nos. 11-32 and 11-33, Scale 111 = 1 ,600', January 25, 1990.

Riverside County Flood Control District, 1995, Photo Nos. 11-34 and 11-35, Scale 1 II = 1,600', January 30, 1995.

Riverside County Flood Control District, 2000, Photo Nos. 11-33- 11-35, Scale 1" = 1 ,600', March 18, 2000.

Riverside County Flood Control District, 2005, Photo Nos. 11-33- 1135, Scale 111 = 1 ,600', July 27, 2005.

Riverside County Flood Control District, 2010, Photo Nos. 11-35- 11-37, Scale 1II= 1,600', March 28, 2010.

Terrain Navigator, Orthophoto Map, Hemet NW, CA, USGS Ref. Code 33116-F8-01-PHT, dated June 19, 2009.

Geotechnical Report- MDP Line C, Stage 4 Project No. Wl75-068- October 2011 21 Inland Foundation Engineering, Inc. APPENDIX A

FIELD AND LABORATORY EXPLORATION AND TESTING

For our field exploration, ten exploratory borings were excavated by means of a truck mounted rotary auger rig at the approximate locations shown on Figure A-13. Logs of the materials encountered were made on the site by a Staff Geologist. These are presented on Figures A-3 through A-12.

Representative undisturbed samples were obtained within our borings by driving a thin-walled steel penetration sampler with successive 30-inch drops of a 140-pound hammer. The number of blows required to achieve each six inches of penetration were recorded on our boring logs and used for estimating the relative consistencies of the subsoils. Two different samplers were used. The first sampler used was a Standard Penetration Sampler for which published correlations relating the number of hammer blows to the strength of the soil are available. The second sampler type was larger in diameter, carrying brass sample rings having inner diameters of 2.41 inches. Undisturbed samples were removed from the sampler and placed in moisture sealed containers in order to preserve the natural soil moisture content. Representative bulk soil samples were obtained from the auger cuttings. All samples were then transported to our laboratory for further observations and testing.

Representative bulk samples were obtained and returned to our laboratory for further testing and observations. The results of this testing are discussed and presented in Appendix B.

Geotechnical Report- MDP Line C, Stage 4 Project No. W175-068- October 2011 A-I Inland Foundation Engineering, Inc. UNIFIED SOIL CLASSIFICATION SYSTEM (ASTM o2'-4~·8=7=---o::-:6:-c-}----··------··-

PRIMARY DIVISIONS GROUP SYMBOLS SECONDARY DIVISIONS ~-··---,...... ------.---C~L~Ec-cAc-N··,- -+---.....,--==~~~--+------~· ffi LU GRAVELS GW ~· WELL GRADED GRAVELS, GRAVEL-SAND MIXTURES, LITTLE OR NO FINES ~ z ~ ~ ~ (LESS r-----+---=_~·--+------1 ::) Ul <( <( z I LU THAN) 5% GP - POORLY GRADED GRAVELS OR GRAVEL-SAND MIXTURES, LITTLE OR NO 0 0 r- FINES FINES ~ uJ>~U-~LU 2: > ~_ ~ U)LU ~~~~~~ ~ 0 :;;! !:::! t? 0 u. ~ ~'"' GRAVEL GM t SILTY GRAVELS, GRAVEL-SAND-SILT MIXTURES U) 0 Ci:~ ~:;i!u.::J WITH 1-----1--~~--+------~--- LU z ~ ~ I FINES GC ~ CLAYEY GRAVELS, GRAVEL-SAND-CLAY MIXTURES ~ U) ;:.-'~ ~ u. 8N r---··------_,__ C_L_E-AN--+---+--~T:::~~<-~------4 (.? 0 w u.'"' ~ z SANDS SW . ,-.,;.: WELL GRADED SANDS, GRAVELLY SANDS, LITTLE OR NO FINES ~ :;;! ~ z ~ Ul <( (LESS <( I I Ul THAN) 5% 0 :2 (§ z ~ ~ SP POORLY GRADED SANDS OR GRAVELLY SANDS, LITTLE OR NO FINES u ~ r- ~ t;; ~ ~ ffi 1;5 FINES ~ Ulg5o~:::J.q SANDS SM SILTY SANDS, SAND-SILT MIXTURES ~ ~~a:~'"' WITH 0 :2 U) FINES ~ sc CLAYEY SANDS, SAND-CLAY MIXTURES

INORGANIC SILTS, VERY FINE SANDS, ROCK FLOUR, SILTY OR CLAYEY r- ML FINE SANDS :1 0 :J U)LO U)UlZ INORGANIC CLAYS OF LOW TO MEDIUM PLASTICITY, GRAVELLY CLAYS, O_-W<( CL :::> -'I SANDY CLAYS, SILTY CLAYS, LEAN CLAYS ~ 0 r­ 0 ::J U) OL ORGANIC SILTS AND ORGANIC SILT-CLAYS OF LOW PLASTICITY 0 w INORGANIC SILTS, MICACEOUS OR DIATOMACEOUS FINE SANDS OR z MH 0 SILTS, ELASTIC SILTS ~ ZU) (.? <(>­ LU U)<( CH INORGANIC CLAYS OF HIGH PLASTICITY, FAT CLAYS z f--' u:: ...JU 1ii OH ORGANIC CLAYS OF MEDIUM TO HIGH PLASTICITY, ORGANIC SILTS

HIGHLY ORGANIC SOILS PT PEAT, MUCK AND OTHER HIGHLY ORGANIC SOILS

SANDSTONES ss

X X SILTSTONES SH X X X X CLAYSTONES cs D 1--~~------+---+--~~-+------i LIMESTONES LS ;=:

SHALE SL

CONSISTENCY CRITERIA BASES ON FIELD TESTS

CONSISTENCY- POCKET** *NUMBER OF BLOWS FINE-GRAIN SOIL TORVANE RELATIVE DENSITY- COARSE- GRAIN SOIL PENETROMETER OF 140 POUND UNDRAINED HAMMER FALLING RELATIVE UNCONFINED RELATIVE SPT * SPT* SHEAR 30 INCHES TO DRIVE A DENSITY CONSISTENCY COMPRESSIVE DENSITY (# BLOWS/FT) (# BLOWS/FT) STRENGTH 21NCH O.D. (%) STRENGTH (tsf) (tsf) (1 3/8 INCH 1.0.) SPLIT BARREL SAMPLER VERY LOOSE <4 0-15 Very Soft <2 <0.13 <0.25 (ASTM -1586 STANDARD LOOSE 4-10 15-35 Soft 2-4 0.13-0.25 0.25-0.5 PENETRATION TEST) MEDIUM 10-30 35-65 Medium Stiff 4-8 0.25-0.5 0.5-1.0 DENSE **UNCONFINED DENSE 30-50 65-85 Stiff 8-15 0.5-1.0 1.0-2.0 COMPRESSIVE STRENGTH IN Very Stiff 15-30 1.0-2.0 2.0-4.0 TONS/SQ.FT. READ VERY DENSE >50 85-100 Hard >30 >2.0 >4.0 FROM POCKET PENETROMETER MOISTURE CONTENT CEMENTATION DESCRIPTION FIELD TEST DESCRIPTION FIELD TEST DRY Absence of moisture, dusty, dry to the touch Weakly Crumbled or breaks with handling or slight finger pressure

1 MOIST Damp but no visible water Moderately Crumbles or breaks wtth considerable finger~ressure I WET Visible free water, usually soil is below water table Strongly Will not crumble or break with finger pressure

EXPLANATION OF LOGS I Figure A-2 I LOG OF BORING Ba01 Elevation: 1579.0 Date(s) Drilled: 7/13/11 Logged by: FWC Drilling Method: Rotary Auger Hammer Type: Auto-Trip Drilling Rig: Mobile B-61 Hammer Weight: 140 lb. Boring Diameter: 8-inches Hammer Drop: 30-inches

SUMMARY OF SUBSURFACE CONDITIONS

0~ This summary applies only at the location of the boring and at the time of drilling. ~ ~ z Subsurface conditions may differ at other locations and may change at this location 0 ~ 0 with the passage of time. The data presented is a simplification of actual conditions UJ ~ wi= g () a:: f- >() J: encountered and is representative of interpretations made during drilling. Contrasting :::) z --<;::- ~~ w ~ U) _j 6 a::~ wo 0 (.9 :::) ro 2 o-:;, IY:() (7.5 inches over 4.5 4 10 100 5

5 5 7 97 8

10 4 3 93 5 very fine to grained, olive, sl y moist, loose to medium dense, interbedded with silt with sand. 5 3 90 15 8

SAND with SILT, fine to urn grained, olive, slightly moist, medium dense, with very thin to thin interbeds of silt or sandy 7 2 99 silt. 7 20

7 2 102 8 SILTY SAND, very fine to fine grained with trace clay, olive, 25 slightly moist, medium dense. 6 4 95 10

SANDY CLAY, very fine to fine grained, red brown, slightly 30 moist, stiff. 5 7 10

SANDY CLAY, very fine to fine grained, olive, slightly moist, stiff. 8 of boring at 34.5 feet. No groundwater or mottling encountered.

Hemet MOP Line 4 Figure No. Whittier Avenue INLAND FOUNDATION ENGINEERING, INC. ,,...... , •. !-_ Hemet, CA ect No. W175-068 A-3 LOG OF BORING Bw02 Elevation: 1582.5 Date(s) Drilled: 7/13/11 Logged by: FWC Drilling Method: Rotary Auger Hammer Type: Auto-Trip Drilling Rig: Mobile B-61 Hammer Weight: 140 lb. Boring Diameter: 8-inches Hammer Drop: 30-inches

SUMMARY OF SUBSURFACE CONDITIONS This summary applies only at the location of the boring and at the time of drilling. Subsurface conditions may differ at other locations and may change at this location with the passage of time. The data presented is a simplification of actual conditions !.!J g ~ encountered and is representative of interpretations made during drilling. Contrasting ::J I 1- data derived from laboratory analysis may not be reflected in these representations. !1.. tn !.!J 6 0 ~

3 7 102 3 SILTV SAND, very fine to fine grained, olive, moist, loose. 5

3 3 105 SILTV SAND, very fine to fine grained, olive, moist, loose, 3 interbedded with thin layers silt or sandy silt.

3 10 103 5

SILTY, CLAYEY SAND, very fine grained, olive, moist, medium dense, interbedded with thin layers sand 4 20 95 7

7 3 102 20 10

8 4 110 14 SILTV SAND, fine to medium grained, olive, moist, medium dense, interbedded with very thin to thin layers sandy silt.

ss 5 5 106 8 very fine to fine grained, red brown, moist, 30 , interbedded with silty sand. 4 7 5 CLAYEY SAND, very fine to fine grained, olive, moist, medium dense.

7 End of boring at 35.5 feet. No groundwater or mottling encountered.

Hemet MOP Line 4 Figure No. Whittier Avenue ~INLAND FOUNDATION ENGINEERING, INC. Hemet, CA P ect No. W175-068 A-4 LOG OF BORING 8~03 Elevation: 1589.0 Date(s) Drilled: 7/13/11 Logged by: FWC Drilling Method: Rotary Auger Hammer Type: Auto-Trip Drilling Rig: Mobile B-61 Hammer Weight: 140 lb. Boring Diameter: 8-inches Hammer Drop: 30-inches

SUMMARY OF SUBSURFACE CONDITIONS ~ This summary applies only at the location of the boring and at the time of drilling. 0 ';j z Subsurface conditions may differ at other locations and may change at this location 0 with the passage of time. The data presented is a simplification of actual conditions w ~ 1- wi= g g 0:: >0 encountered and is representative of interpretations made during drilling. Contrasting ~ :J -<( I I (f) z 1- 0.. (f) data derived from laboratory analysis may not be reflected in these representations. s ti :J ~0.. 0.. <( 0 0 >-<+=- .-J2 w 0:: _] 0 0:: 0 wo 0 (.9 3 co 2 o-.3: 0::0 (8 inches over 4

ss 27 10 122 50/5" SILTY. CLAYEY SAND, fine to medium grained, olive brown, 30 slightly moist to moist, dense, moderately to strongly cemented.

8 End of boring at 32.5 feet. No groundwater or mottling encountered.

Hemet MOP Line 4 Figure No. Whittier Avenue INLAND FOUNDATION ENGINEERING, INC. .,...... , •• !--_ Hemet, CA Pro No. W175-068 A-5 LOG OF BORING Bm04 Elevation: 1595.0 Date(s) Drilled: 7/13/11 Logged by: FWC Drilling Method: Rotary Auger Hammer Type: Auto-Trip Drilling Rig: Mobile B-61 Hammer Weight: 140 lb. Boring Diameter: 8-inches Hammer Drop: 30-inches

SUMMARY OF SUBSURFACE CONDITIONS This summary applies only at the location of the boring and at the time of drilling. ~ ~ z Subsurface conditions may differ at other locations and may change at this location ~ 0 with the passage of time. The data presented is a simplification of actual conditions UJ ~ wi= g () 0:: f- >() encountered and is representative of interpretations made during drilling. Contrasting :::J -<( I I ~ z (f) data derived from laboratory analysis may not be reflected in these representations. f- :::J f- 0.. s (f) ~0.. 0.. <( () 0 >-<;:' _J:2 w 0:: (f) _J 6 rYo wo 0 t9 :::J OJ :2 CiS 0::()

4 7 106 4

5 SILTV SAND, fine to coarse grained, olive, moist, loose, 3 8 107 interbedded with thin layers sand. 4 SAND, fine to coarse grained, olive, slightly moist, loose.

SILTV SAND, very fine to fine grained with trace clay, olive, 3 3 109 moist, loose to medium dense. 4

3 7 103 15 5

fine to medium grained, olive, slightly moist, medium 6 7 106 9 20 fine to medium grained, olive, moist, medium

6 3 106 8

SILTV SAND, very fine to fine grained, olive, moist, medium 25 dense, interbedded with very thin to thin layers silt or sandy silt. ss 4 3 103 7

CLAYEY SAND, fine to medium grained, red brown, slightly moist, medium dense, strongly cemented. 30 13 7 9 SILTV, CLAYEY SAND, very fine to fine grained, olive brown, slightly moist, medium dense

4 4 very fine to fine grained, olive, slightly moist, 4

End of boring at 35.5 feet. No groundwater or mottling encountered.

Hemet MOP Line 4 Figure No. Whittier Avenue INLAND FOUNDATION ENGINEERING, INC. Hemet, CA No. W175-068 A-6 LOG OF BORING s .. os Elevation: 1599.0 Date(s) Drilled: 7/14/11 Logged by: FWC Drilling Method: Rotary Auger Hammer Type: Auto-Trip. Drilling Rig: Hammer Weight: 140 lb. Boring Diameter: 8-inches Hammer Drop: 30-inches

SUMMARY OF SUBSURFACE CONDITIONS ~ This summary applies only at the location of the boring and at the time of drilling. 2...- ~ z Subsurface conditions may differ at other locations and may change at this location 2...- 0 with the passage of time. The data presented is a simplification of actual conditions LU ~ g 0 0::: f- w[3 encountered and is representative of interpretations made during drilling. Contrasting :::J z 2:<( I :C ~ f- :::J f- ll. (f) data derived from laboratory analysis may not be reflected in these representations. 5 (f) ~ll. ll. 0 0 >-<+::- _J2 LU ~ (f) _J 0 wo 0 (.9 :::J OJ 2 iSs 0:::0 (6 inches over 5

4 3 107 very fine to fine grained, olive, slightly moist, 5 5

4 2 103 6

10 ~::.L.!~~!:!.. very fine to fine grained, olive, moist, loose, interbedded with sand with silt. 5 104

SILTV SAND, very fine to fine grained, ive, slightly moist, 5 101 15 loose.

3 101 20

Hemet MOP Line 4 Figure No. Whittier Avenue Hemet, CA ...... ~ .... + No. W175-068 A-7 LOG OF BORING Bm06 Elevation: 1606.0 Date(s) Drilled: 7/14/11 Logged by: FWC Drilling Method: Rotary Auger Hammer Type: Auto-Trip Drilling Rig: Mobile B-61 Hammer Weight: 140 lb. Boring Diameter: 8-inches Hammer Drop: 30-inches

SAMPLES SUMMARY OF SUBSURFACE CONDITIONS e.._.~ This summary applies only at the location of the boring and at the time of drilling. ~ z Subsurface conditions may differ at other locations and may change at this location ~ 0 w ~ with the passage of time. The data presented is a simplification of actual conditions 1- wi= g encountered and is representative of interpretations made during drilling. Contrasting ~ n:: >0 (/) ::::J z -<( I data derived from laboratory analysis may not be reflected in these representations. 1- ::::J 1- s (/) 0.. 0 ~~ w _j 6 &'[ wo 0 [I) 2 o~ n::o

ss 4 3 108 5 4 SILTV SAND, fine to medium grained, olive, moist, loose, interbedded with thin layers of sand.

2 7 95 10 SILTV SAND, very fine to fine grained with trace clay, olive, 4 moist, loose.

SILTV SAND, very fine to fine grained, ive, moist, loose, 4 85 interbedded with sandy silt. 18 15 5

3 7 97 20 6 fine to medium grained, olive, moist, loose to medium dense, interbedded with thin layers sandy silt.

ss 6 3 107 25 6

3 5 30 3

22

End of boring at 34.5 feet. No groundwater or mottling encountered.

Hemet MOP Line 4 Figure No. Whittier Avenue INLAND FOUNDATION ENGINEERING, INC. ,,...... _., •. t-_ Hemet, CA D~-~=~·~4- No. W175-068 A-8 LOG OF BORING Bm07 Elevation: 1614.5 Date(s) Drilled: 7/14/11 Logged by: FWC Drilling Method: Rotary Auger Hammer Type: Auto-Trip Drilling Rig: Mobile B-61 Hammer Weight: 140 lb. Boring Diameter: 8-inches Hammer Drop: 30-inches

SUMMARY OF SUBSURFACE CONDITIONS ~ This summary applies only at the location of the boring and at the time of drilling. ~ ~ z Subsurface conditions may differ at other locations and may change at this location 0 0 with the passage of time. The data presented is a simplification of actual conditions w ~ wi= g encountered and is representative of interpretations made during drilling. Contrasting 0:: f- >() ~ z -~ I ~ f- ~ f- data derived from laboratory analysis may not be reflected in these representations. ~ (/) ~D.. 0.. >-c;:- ....~::;;;: w g 6 IY'O-c. wo 0 co 2 o~ 0::()

3 6 100 3

SAND with SILT, fine to coarse grained, olive, slightly moist, 5 -P.r~...... rt---. loose. ~~~~~~~----~--~--~~~--~--~----_J SILTY SAND, fine to medium grained with trace clay, olive, slightly moist, loose. 2 7 106 3

10

4 6 110 fine to coarse grained, olive, moist, medium 7

15

4 13 103 , olive, moist, 5

20

6 6 104 10

25

ss 3 11 108 6

SANDY CLAY, very fine to fine grained, olive brown, slightly 30 moist, very hard, moderately cemented.

12 t------f'-'L-L~b-h CLAYEY SAND, very fine to fine grained, olive brown, slightly ist, dense, moderately cemented. End of boring at 32.5 feet. No groundwater or mottling encountered.

Hemet MOP Line 4 Figure No. Whittier Avenue ~INLAND FOUNDATION ENGINEERING, INC. Hemet, CA Prni,.rt No. W175-068 A-9 lOG OF BORING Bm08 Elevation: 1619.7 Date(s) Drilled: 7/14/11 Logged by: FWC Drilling Method: Rotary Auger Hammer Type: Auto-Trip Drilling Rig: Mobile B-61 Hammer Weight: 140 lb. Boring Diameter: 8-inches Hammer Drop: 30-inches

SUMMARY OF SUBSURFACE CONDITIONS ~ ~ This summary applies only at the location of the boring and at the time of drilling. 0 Subsurface conditions may differ at other locations and may change at this location 0~ z ~ 0 with the passage of time. The data presented is a simplification of actual conditions UJ ~ g 0 a::: f- wi= encountered and is representative of interpretations made during drilling. Contrasting :::J I :C ~ z 2::i (f) data derived from laboratory analysis may not be reflected in these representations. f- :::J f- 0.. s (f) 0.. <( 0 0 >-c- ~~ UJ a::: (f) ....! 6 a:::u UJO 0 (.9 :::J aJ ::2: oE:: a:::o (4.25 inches over

3 5 100 3 SILTV, CLAYEY SAND, very fine to fine grained, olive, moist, 5 loose.

3 16 98 SILTV SAND, fine to medium grained, olive, moist, loose, 3 interbedded with thin layers of sand with silt. 10

3 9 100 4 15

4 9 94 5 20

10 102 SAND with SILT, fine to medium grained, olive, slightly moist, 5 medium dense. 9 25

ss 8 3 107 14 SANDY CLAY, very to fine grained, olive brown, slightly 30 -+7'+-S+-:---h moist, stiff, moderate cemented. =~=..:.-=...:::....:..:=-• fine to medium grained, olive brown, slightly moist, ium dense, moderately cemented. 4 J-----+...... 4h-IAI-h SAND, fine to coarse grained, red brown, slightly moist, edium dense. End of boring at 33.5 feet. No groundwater or mottling encountered.

Hemet MOP Line 4 Figure No. Whittier Avenue ~INLAND FOUNDATION ENGINEERING, INC. Hemet, CA

....., ...... T No. W175-068 A-10 LOG OF BORING B-09 Elevation: 1624.0 Date(s) Drilled: 7/14/11 Logged by: FWC Drilling Method: Rotary Auger Hammer Type: Auto-Trip Drilling Rig: Mobile B-61 Hammer Weight: 140 lb. Boring Diameter: 8-inches Hammer Drop: 30-inches

SUMMARY OF SUBSURFACE CONDITIONS ~ ~ This summary applies only at the location of the boring and at the time of drilling. ::..- z Subsurface conditions may differ at other locations and may change at this location ~ 0 with the passage of time. The data presented is a simplification of actual conditions UJ ~ I- wf= §: 0 n:: >0 encountered and is representative of interpretations made during drilling. Contrasting :::J z --c;::-- ....1:2 lU ~ (f) ....1 6 fYO wo 0 (.9 :::J r£l :2 oE:: n::o (6.5 inches over 3.5

5 103 5 .· .· • SM SILTY Y SAND, very fine to fine grained, olive, moist, loose.

2 10 106 10 very fine to fine grain olive, moist, 4

SILTY SAND, very fine to fine grained with trace clay, olive, moist, loose.

SAND with SILT, fine to coarse grained, olive, slightly moist, 3 23 90 15 medium dense, interbedded with thin layers sandy silt or silty 5 sand.

4 10 105 20 6 SILTY SAND, fine to medium grained, olive, moist, medium dense, interbedded with thin layers sandy silt or silt.

5 6 100 25 6

SANDY CLAY, very fine to medium grained, red brown, moist, stiff, moderately cemented. 9 126 CLAYEY SAND, fine to coarse grained, red brown, moist, 7 10 30 medium dense.

11 End of boring at 34.5 feet. No groundwater or mottling encountered.

Hemet MOP Line 4 Figure No. Whittier Avenue ~INLAND FOUNDATION ENGINEERING, INC. Hemet, CA No. W175-068 A-11 LOG OF BORING B-10 Elevation: 1629.5 Date(s) Drilled: 7/14/11 Logged by: FWC Drilling Method: Rotary Auger Hammer Type: Auto-Trip Drilling Rig: Mobile B-61 Hammer Weight: 140 lb. Boring Diameter: 8-inches Hammer Drop: 30-inches

SUMMARY OF SUBSURFACE CONDITIONS

0~ This summary applies only at the location of the boring and at the time of drilling. Subsurface conditions may differ at other locations and may change at this location 0~ z ~ 0 with the passage of time. The data presented is a simplification of actual conditions w ~ wi= g 9 encountered and is representative of interpretations made during drilling. Contrasting 0:: f- >() I ::J z -<( I data derived from laboratory analysis may not be reflected in these representations. ~ f- ::J f- 0.. (f) s (f) 0.. <( () 0 >-c- ~~ 0:: (f) 6 rYU wo 5 (.9 ::J a:i ::2! os 0::() 5 inches over 4.5 6 5 107 4

5

2 8 95 3

10 very fine to fine grained with trace clay, olive, stiff. 4 9 101 6

15 ~:.L!-il.!.~6 very fine to grained, olive, slightly moist, medium dense, weakly cemented, interbedded with thin layers sandy silt or silt. ss 5 4 98 6

20 ~~~~~~~~~~=-~--~----~~~~~----~~---4 SAND with SILT, fine to medium grained, olive brown, slightly moist, medium dense, weakly cemented. ss 7 2 104 8

25

ss 8 4 100 12

30 1 End of boring at 31.5 feet. No groundwater or mottling encountered.

Hemet MOP Line 4 Figure No. Whittier Avenue ~INLAND FOUNDATION ENGINEERING, INC. Hemet, CA P No. W175-068 A-12 SITE PLAN Hemet MOP Line C, Stage 4 Storm Drain Project Hemet, California

INLAND FOUNDATION ENGINEERING, INC. 1310 South Santa Fe Avenue San Jacinto, California LEGEND 951 654-1555 FAX 951 654-0551

DRAWN BY: DRL JOB NO.: W175-06B + = Approximate Location of Boring SCALE: Not to Scale DATE: 10/31/11 A-13 APPENDIX B

LABORATORY OAT A

Representative bulk soil samples were obtained in the field and returned to our laboratory for additional observations and testing. Laboratory testing was generally performed in two phases. The first phase consisted of testing in order to determine the compaction of the existing natural soil and the general engineering classifications of the soils across the site. This testing was performed in order to estimate the engineering characteristics of the soil and to serve as a basis for selecting samples for the second phase of testing. The second phase consisted of soil mechanics and analytical testing. This testing included direct shear testing, consolidation testing, and testing to estimate the corrosion potential of the soils to concrete. These tests were performed in order to provide a means of developing specific design recommendations based on the strength and chemical characteristics of the soil.

CLASSIFICATION AND COMPACTION TESTING

Unit Weight and Moisture Content Determinations: Each undisturbed sample was weighed and measured in order to determine its unit weight. A small portion of each sample was then subjected to testing in order to determine its moisture content. This testing was performed in accordance with the ASTM Standards 02937-04 and 02216- 05. This was used in order to determine the dry density of the soil in its natural condition. The results of this testing are shown on the Boring Logs (Figure Nos. A-3 through A-12).

Maximum Density-Optimum Moisture Determinations: Representative soil types were selected for maximum density determinations. This testing was performed in accordance with ASTM 01557-09. The maximum densities are compared to the field densities of the soil in order to determine the existing Relative Compaction. This data is useful in estimating the strength and compressibility of the soil. The results of this testing are shown on Figure Nos. B-4 and B-5.

Classification Testing: Eight soil samples were selected for classification testing. This testing consists of mechanical grain size analyses and Atterberg Limits determinations. This testing was performed in accordance with the ASTM Standards 0422-63(2002) and 04318-05. These tests provide information for developing

Geotechnical Report MDP Line C, Stage 4 Project No. W175-068- October 2011 B-1 Inland Foundation Engineering, Inc. classifications for the soil in accordance with the Unified Classification System. This classification system categorizes the soil into groups having similar engineering characteristics. The results of this testing are very useful in detecting variations in the soils and in selecting samples for further testing. The results of this testing are presented on Figure Nos. B-6 and B-7.

SOIL MECHANIC'S TESTING

Direct Shear Testing: Six samples were selected for Direct Shear Testing. This testing was performed in accordance with the ASTM Standard 03080-04. This testing measures the shear strength of the soil under various normal pressures and is used in developing parameters for foundation design and lateral design. Testing was performed using recompacted test specimens which were saturated prior to testing. Testing was performed using a strain controlled test apparatus with normal pressures ranging from 934 to 2230 pounds per square foot. The results of this testing are shown on Figure No. B-8.

Consolidation Testing: Three samples were selected for consolidation testing. This testing was performed in accordance with the ASTM Standard 02435-04. For this test, relatively undisturbed samples were selected and carefully trimmed into a one inch thick by 2.41-inch diameter consolidometer. The consolidometer was moisture sealed in order to preserve the natural moisture content during the initial stages of testing. Loads ranging up to 22,666.1 pounds per square foot were applied progressively with the rate of settlement declining to a value of 0.0002 inches per hour prior to the application of each subsequent load. At a preselected load, water was introduced into the consolidometer in order to observe the potential for saturation collapse. The result of this testing is presented graphically on Figure Nos. B-9 through B-11.

Expansion Testing: Three samples were selected for Expansion testing. Expansion testing was performed in accordance with the UBC Standard 18-2. This testing consists of remolding 4-inch diameter by 1-inch thick test specimens to a moisture content and dry density corresponding to approximately 50 percent saturation. The samples are subjected to a surcharge of 144 pounds per square foot and allowed to reach equilibrium. At that point the specimens are inundated with distilled water. The linear expansion is then measured until complete. The results of this testing are shown on Figure No. B-12.

Geotechnical Report- M,DP Line C, Stage 4 Project No. W175-068- October 2011 B-2 Inland Foundation Engineering, Inc. ANALYTICAL TESTING

Five samples were selected to determine the concentration of soluble sulfates, chlorides, pH level, and resistivity of and within the on-site soils. The following table presents the results of this testing:

B-01 3.75-11.5 <0.001 75 3,975 7.9 B-02 13.0-17.0 0.024 255 1,482 8.1 B-03 4.5-9.0 0.006 60 3,543 7.8 B-07 0.63-4.0 0.007 75 6,864 7.2 B-09 5.0-9.5 0.002 180 1,961 7.9

GENERAL

All laboratory testing has been conducted in conformance with the applicable ASTM test methods by personnel trained and supervised in conformance with our QA/QC policy. Our test data only relates to the specific soils tested. Soil conditions typically vary and any significant variations should be reported to our laboratory for review and possible testing. The data presented in this report are for the use of Albert A. Webb Associates and Riverside County Flood Control and Conservation District only and may not be reproduced or used by others without written approval of Inland Foundation Engineering, Inc.

Geotechnical Report- MDP Line C, Stage 4 Project No. WJ75-068- October 2011 B-3 Inland Foundation Engineering, Inc. 160 \ \ \

155 \ \

\ 150 \ \ \ _\ \ 145 \ \ I \ I \ \ 140 \ \ \

135 \ \ / • '\. \ ...... '\. \ 130 -...at -K" / '\. \ u.. v' ' ~ \ () .M' / "-•\. \ 0.. 125 / "'~ \ ~ rr( ~~ \ f- \.'\. ~ U5z \.'\. \\. \ w ~\\ \ 0 120 I= '\'flo.\ '\. >- __.r.&- \. ~\ 0::: ~ 'II' 0 \. ?t-i '\ " '\. "\. '\ 115 \. '\ ~ '\. '\. '\. I'- 110 " " " " 105 "" " '-... " '-... 100 0 5 10 15 20 25 " 30

MOISTURE CONTENT, %

Specimen Identification Classification Max.Density MC% e B-01 3.8 CLAYEY SAND SC 133.0 8.5 B-02 13.0 SILTY, CLAYEY SAND SC-SM 128.0 10.0 B-03 4.5 SILTY, CLAYEY SAND SC-SM 128.5 10.0 * B-05 5.0 SILTY SAND SM 129.5 9.0 B-07 0.6 SILTY SAND SM 120.5 10.0 0 B-09 5.0 SILTY SAND SM 130.0 9.0 PROJECT Hemet MDP Line 4 PROJECT NO. W175-068 Whittier Avenue DATE July 14, 2011 MAXIMUM DENSITY-OPTIMUM MOISTURE CURVES Inland Foundation Engineering, Inc FIGURE NO. B-4 f"

\ \ 160 \ \ \ \ 155 ·"' \ \ 150 \ \ \ \ 145 \ I \ 140 \ \ \

135 '\ \ '\

130 '\ '\ _'... u.. '\ 0 ~ ...... '\. n. 125 L '\. >-" / "' '\. '\ f- • enz i'\. w '\ 0 120 '\ & '\. 0 '\ '\. '\. 115 '\ '\ '\. 1'\ 110 " "- ·""" " "- 105 " " "- ~

"-.., 100 "'-... 0 5 10 15 20 25 30

MOISTURE CONTENT, %

Specimen Identification Classification Max.Density MC% • B-10 4.0 SILTY, CLAYEY SAND SC-SM 128.5 9.0

PROJECT Hemet MOP Line 4 PROJECT NO. W175-068 Whittier Avenue DATE July 14, 2011 MAXIMUM DENSITY-OPTIMUM MOISTURE CURVES Inland Foundation Engineering, Inc FIGURE NO. B-5 U.S. SIEVE OPENING IN INCHES I U.S. SIEVE NUMBERS I HYDROMETER 4 2 1 1/2 3 6 10 16 30 50 100 200 6 3 1.5 3/4 8 ~ 8 14 20 40 70 140 100 I II I . i I' . r I I I I ~ ~ ': ~ lli 90 ~'""' 1\ '\ \ l~ ,\\ : ~~ 80 \ \~·~ \ p ~ E R70 \\ ~ \ c ~ \\ I= \\ ~ \ 1\\ \\ I~ 60 I F I \ \\ N E 50 I\\ \ \ R \ 1\~ B y 40 ~\ w E \\\ I G3Q \\ H T \

20

10

0 100 10 1 0.1 0.01 0.001 GRAIN SIZE IN MILLIMETERS SAND COBBLES SILT OR CLAY fine Specimen Identification Classification S.G. LL PL PI Cc Cu • B-01 3.8 CLAYEY SAND SC 26 15 11 IIJ B-02 13.0 SILTY, CLAYEY SAND SC-SM 18 14 4 .... B-03 4.5 SILTY, CLAYEY SAND SC-SM 19 14 5 B-05 5.0 SILTY SAND SM 15 13 2 *0 B-07 0.6 SILTY SAND SM 17 15 2 Specimen Identification 0100 060 030 010 %Gravel %Sand %Silt %Clay • B-01 3.8 12.70 0.16 5.7 51.4 42.9 IIJ B-02 13.0 4.75 0.12 0.0 54.9 45.1 .... B-03 4.5 9.50 0.32 0.122 0.7 79.7 19.6 B-05 5.0 4.75 0.27 0.098 0.0 76.8 23.2 *0 B-07 0.6 9.50 0.22 0.091 0.4 76.2 23.4 PROJECT Hemet MOP Line 4 PROJECT NO. W175-068 Whittier Avenue DATE July 14, 2011 GRADATION CURVES Inland Foundation Engineering, Inc FIGURE NO. B-6 , U.S. SIEVE OPENING IN INCHES I U.S. SIEVE NUMBERS I HYDROMETER 6 4 3 2 1.5 1 3/4 1/2 8 3 ~ 6 8 10 1416 20 30 40 so 70 1oo140 2oo 100 I II I . I )I rr ' I ~ I I I 1\~ 90

\ ·~ 80 '\

\ . \\ p E R70 ,\ c I~ E \~ N T 60 '\ I F \ ,\ I \ N \ E 50 R :\ B y 40 \ ~ w E I G3Q ~ H T \ \ 20

10

0 100 10 1 0.1 0.01 0.001 GRAIN SIZE IN MILLIMETERS GRAVEL SAND COBBLES SILT OR CLAY coarse fine coarse medium I fine Specimen Identification Classification S.G. LL PL PI Cc Cu • B-09 5.0 SILTY SAND SM 20 19 1 li! B-09 13.8 SILTY SAND SM 17 16 1 ... B-10 4.0 SILTY, CLAYEY SAND SC-SM 21 15 6

Specimen Identification 0100 060 030 010 %Gravel %Sand %Silt I %Clay • B-09 5.0 9.50 0.13 0.2 58.6 41.2 li! B-09 13.8 4.75 0.36 0.147 0.0 81.1 18.9 ... B-10 4.0 9.50 0.12 0.3 54.2 45.5

PROJECT Hemet MOP Line 4 PROJECT NO. W175-068 Whittier Avenue DATE July 14, 2011 GRADATION CURVES Inland Foundation Engineering, Inc

\.. FIGURE NO. B-7 2.5

s H E A R s T R E N G T H

k s f

O.OL------~------~------L------~------~ 0.0 0.5 1.0 1.5 2.0 2.5

NORMAL PRESSURE, ksf

Specimen Identification Classification Phi Cohesion DD MC% • B-01 3.8 CLAYEY SAND SC 34 0.108 120 10 III B-02 14.5 SILTY, CLAYEY SAND SC-SM 26 0.060 83 37 ... B-03 4.5 SILTY, CLAYEY SAND SC-SM 33 0.037 116 12 * B-07 0.6 SILTY SAND SM 29 0.117 109 12 0 B-09 5.0 SILTY SAND SM 30 0.098 117 11 0 B-10 4.0 SILTY, CLAYEY SAND SC-SM 32 0.074 116 11 PROJECT Hemet MOP Line 4 PROJECT NO. W175-068 Whittier Avenue DATE July 14, 2011 SHEAR TEST DIAGRAM Inland Foundation Engineering, Inc FIGURE NO. B-8 0

...... 1

'll-..__

2 ""~ \ 3 \ I

4 \ s T \ R A 1\ I 5 . N \ % \ 6 \ 1\ 1\. 7 ......

~ ...... 8 ...... \ ...... \ -- \ 9 --- """' :.e·

10 5 100 1,000 10,000 10

STRESS, psf

Specimen Identification Classification DD MC% • B-04 17.5 SANDSP 108 6 IZl

.t. * 0 0 PROJECT Hemet MOP Line 4 PROJECT NO. W175-068 Whittier Avenue DATE July 14, 2011 CONSOLIDATION TEST Inland Foundation Engineering, Inc

\. FIGURE NO. B-9 ~ r ~

0 -...: I'-- ~ ._, ~

1 ~ ~

2 0. ~ \ 3 •\ \ \ 4 s T R ~ A r--..1' 5 1\ I N ~ % ~ 1'---- 6 \ \ ~ ~ -r-. 1----~ 7

8

9

10 5 100 1,000 10,000 10

STRESS, psf

Specimen Identification Classification DD MC% • B-06 13.5 SILTY SAND SM 85 18 III ... * 0

¢ PROJECT Hemet MDP Line 4 PROJECT NO. W175-068 Whittier Avenue DATE July 14, 2011 CONSOLIDATION TEST Inland Foundation Engineering, Inc FIGURE NO. B-10 r ,.,

0 ...... r--.., 1 ~ '~ 2 ~ 3 "" \ 4 \. s \ T R \ A \ I 5 N \

% 6 !\ ~~--- 7 \ "'--~ ~ r-...... \ 8 -----\ 9

10 5 100 1,000 10,000 10

STRESS, psf

Specimen Identification Classification DD MC% • B-06 18.5 SILTY SAND SM 99 7 1%1 A * 0

I) PROJECT Hemet MDP Line 4 PROJECT NO. W175-068 Whittier Avenue DATE July 14, 2011 CONSOLIDATION TEST Inland Foundation Engineering, Inc

\.. FIGURE NO. B-11 ~ EXPANSION TEST SUMMARY

B-01 3.75-11.5 114.6 8.5 30 B-02 13.0-17.0 111.3 8.7 19 B-09 5.0-9.5 112.2 9.1 8

Geotechnical Report MDP Line C, Stage 4 Project No. W175-068- October 2011 B-12 Inland Foundation Engineering, Inc. APPENDIX C

CLOSEST DISTANCES BETWEEN SITE AND FAULT RUPTURES

Geotechnical Report- MDP Line C, Stage 4 Project No. W/75-068- October 2011 C-1 Inland Foundation Engineering, Inc. APPENDIX C

CLOSEST DISTANCES BETWEEN SITE AND FAULT RUPTURES

NO. FAULT NAME CD 1DRP CD 2DRP CDIST CLOD IS CD EPI CD HYPO

1 SAN JACINTO-SAN JACINTO VALLEY 2.4(1.8) 2.4 2.4 2.4 2.4 2.6 km 2 SAN JACINTO-ANZA 3.8(2.4) 3.8 3.8 3.8 4.7 4.8 km 3 SAN ANDREAS - Whole M-la 32.4 32.4 32.4 32.4 32.4 32.4 km 4 SAN ANDREAS - SB-Coach. M-lb-2 32.4 32.4 32.4 32.4 32.4 32.4 km 5 SAN ANDREAS - San Bernardino M-1 32.4 32.4 32.4 32.4 32.4 32.4 km 6 SAN ANDREAS - SB-Coach. M-2b 32.4 32.4 32.4 32.4 32.4 32.4 km 7 ELSINORE (TEMECULA) 32.4 32.4 32.4 32.4 32.4 32.5 km 8 ELSINORE (GLEN IVY) 37.5 37.5 37.5 37.5 38.1 38.1 km 9 ELSINORE (JULIAN) 40.3 40.3 40.3 40.3 40.9 40.9 km 10 SAN JACINTO-SAN BERNARDINO 40.4 40.4 40.4 40.4 41.5 41.5 km 11 PINTO MOUNTAIN 41.7 41.7 41.7 41.7 42.5 42.5 km 12 SAN ANDREAS - Coachella M-lc-5 49.7 49.7 49.7 49.7 50.2 50.2 km 13 SAN JACINTO-COYOTE CREEK 52.0 52.0 52.0 52.0 53.0 53.1 km 14 BURNT MTN. 56.9 56.9 56.9 56.9 57.3 57.3 km 15 CHINO-CENTRAL AVE. (Elsinore) 57.3 57.3 57.3 57.3 58.4 58.4 km 16 EUREKA PEAK 62.2 62.2 62.2 62.2 62.6 62.6 km 17 WHITTIER 64.1 63.5 64.0 64.0 64. 6 65.1 km 18 CLEGHORN 64. 9 64. 9 64.9 64. 9 65.1 65.1 km 19 CUCAMONGA 66.6 66.6 66.6 66.6 67. 6 67.6 km 20 LANDERS 68.2 68.2 68.2 68.2 68.7 68.7 km 21 NORTH FRONTAL FAULT ZONE (East) 68.3 55.5 57.0 57.0 56.4 57.7 km 22 SAN JOAQUIN HILLS 68.0 68.0 68.0 68.0 69.4 69.5 km 23 NORTH FRONTAL FAULT ZONE (West) 69.9 56.7 58.1 58.1 57.5 58.7 km 24 HELENDALE - S. LOCKHARDT 71.0 71.0 71.0 71.0 71.7 71.7 km 25 EARTHQUAKE VALLEY 70.9 70.9 70.9 70.9 71. 9 71.9 km 26 LENWOOD-LOCKHART-OLD WOMAN SPRGS 74.8 74.8 74.8 74.8 75.5 75.5 km 27 NEWPORT-INGLEWOOD (Offshore) 75.8 75.8 75.8 75.8 75.8 75.8 km 28 JOHNSON VALLEY (Northern) 79.0 79.0 79.0 79.0 79.4 79.4 km 29 SAN ANDREAS - 1857 Rupture M-2a 79.2 79.2 79.2 79.2 80.2 80.2 km 30 SAN ANDREAS - Mojave M-1c-3 79.2 79.2 79.2 79.2 80.2 80.2 km 31 SAN ANDREAS - Cho-Moj M-1b-1 79.2 79.2 79.2 79.2 80.2 80.2 km 32 SAN JOSE 79.6 79.6 79.6 79.6 80.2 80.2 km 33 ROSE CANYON 80.7 80.7 80.7 80.7 81.1 81.1 km 34 SIERRA MADRE 84.1 84.1 84.1 84.1 85.3 85.3 km 35 EMERSON So. - COPPER MTN. 84.7 84.7 84.7 84.7 84.7 84.7 km 36 PUENTE HILLS BLIND THRUST 86.7 86.7 86.8 86.8 88.0 88.1 km 37 NEWPORT-INGLEWOOD (L.A.Basin) 90.5 90.5 90.5 90.5 91. 1 91.1 km 38 SAN JACINTO - BORREGO 92.5 92.5 92.5 92.5 93.6 93.6 km 39 CALICO - HIDALGO 94.4 94.4 94.4 94.4 94.7 94.7 km 40 PISGAH-BULLION MTN.-MESQUITE LK 97.7 97.7 97.7 97.7 97.7 97.7 km 41 CLAMSHELL-SAWPIT 99.4 99.4 99.4 99.4 100.5 100.5 km

EXPLANATION

CD lDRP Closest distance to projection of rupture area along fault trace. CD-2DRP Closest distance to surface projection of the rupture area. CDIST Closest distance to seismogenic rupture. CLODIS Closest distance to subsurface rupture. CD EPI Closest epicentral distance. CD HYPO Closest hypocentral distance.

Geotechnical Report- MDP Line C, Stage 4 Project No. W175-068 October 2011 C-2 Inland Foundation Engineering, Inc. APPENDIX D

SOIL CORROSIVITY EVALUATION- HDR I SCHIFF

Geotechnical Report- MDP Line C, Stage 4 Project No. W175-068- October 2011 D-1 Inland Foundation Engineering, Inc. SCHIFF www.hdrinc.com Corrosion Control and Condition Assessment (C3A} Department

SOIL CORROSIVITY EVALUATION

for the

RIVERSIDE COUNTY FLOOD CONTROL AND WATER CONSERVATON DISTRICT-HEMET MOP LINE C-STAGE 4 STORM DRAIN

in [ 1 HEMET, CALIFORNIA

prepared for

INLAND FOUNDATION ENGINEERING, INC. 1310 South Santa Fe San Jacinto, CA 92583

Project No.: IFE #W175-068

PROJECT MANAGER: MR. LARRY STRAHM P.E., G.E.

prepared by

HDR I SCHIFF Consulting Corrosion Engineers 431 West Baseline Road Claremont, California 91711

HDR ISCHIFF# 11-0774SCS

August 17, 2011

431 West Baseline Road · Claremont, CA 91711 Phone: 909.626.0967 · Fax : 909.626.3316 f 1 EXECUTIVE SUMMARY I The proposed 60- to 72-inch diameter stmm drain will run approximately 6,600 feet. Materials being considered are reinforced concrete pipe (RCP) and concrete structures. The storm drain will have 6-15 feet of cover. The water table is reportedly not encountered to a depth of35.5 feet during boring explorations.

A soil corrosivity analysis along the proposed storm drain alignment was requested. Laboratory tests on ten soil samples supplied by Inland Foundation Engineering, Inc. have been completed. The purpose of these tests was to determine soil corrosivity regarding the proposed storm drain and concrete structures.

The alignment begins 150 feet east of Palm A venue along Whittier A venue to approximately 100 feet east of San Jacinto Street in the City of San Jacinto, California.

This soil is classified as severely conosive to fenous metals, aggressive to copper, and aggressive with respect to exposure of reinforci ng steel to the migration of chlmide.

Based on this investigation, reinforced construction materials are satisfactory when following the material recommendations outlined in this report.

J

Inland Foundation Engineering, Inc . August 17, 2011 HDR/Schiff # 11 -077 4SCS Page i TABLE OF CONTENTS

Executive Summary ...... i

Table of Contents ...... ii

Introduction ...... 1

Test Procedures ...... 1

Laboratory Tests on Soil Samples ...... 1

Discussion ...... 1

Conclusions ...... 2

Recommendations ...... 3

Reinforced Concrete Pipe ...... 3

All Pipe ...... 3

Concrete Structures ...... 3

Closure ...... 3

Works Cited ...... 5

Inland Foundation Engineering, Inc. August 17, 2011 HDR/Schiff # 11-0774SCS Page ii r ! 1 INTRODUCTION

A soil corrosivity analysis along the proposed storm drain alignment was requested. Laboratory [1 tests on ten soil samples supplied by Inland Foundation Engineering, Inc. have been completed. The purpose of these tests was to determine soil corrosivity regarding the proposed storm drain and concrete structures.

The proposed 60- to 72-inch diameter storm drain will run approximately 6,600 feet. Materials being considered are reinforced concrete pipe and concrete structures. The storm drain will have 6- 15 feet of cover. The water table is reportedly not encountered to a depth of 35.5 feet during boring explorations.

The alignment begins 150 feet east of Palm A venue along Whittier Avenue to approximately 100 feet east of San Jacinto Street in the City of San Jacinto, California.

The scope of this study is limited to a determination of soil corrosivity and general corrosion control recommendations for materials planned for construction.

TEST PROCEDURES

Laboratory Tests on Soil Samples

The electrical resistivity of each o e seven samples was easured in a soil box per ASTM G 187

[ ) in its as-received condition and aga1 1th distilled water. Resistivities are at about their lowest value when the soil is saturated. The pH of the saturated samples was measured per ASTM G51. A 5:1 water:soil extract from each sample was chemically analyzed for the major soluble salts commonly found in soil per ASTM D4327, D6919, and D513. Test results are shown ll in Table 1.

DISCUSSION

' J A major factor in determining soil corrosivity is electrical resistivity. The electrical resistivity of · a soil is a measure of its resistance to the flow of electrical current. Corrosion of buried metal is an electrochemical process in which the amount of metal loss due to corrosion is directly proportional to the flow of electrical current (DC) from the metal into the soil. Corrosion currents, following Ohm's Law, are inversely proportional to soil resistivity. Lower electrical resistivities result from higher moisture and soluble salt contents and indicate corrosive soil.

Inland Foundation Engineering, Inc. August 17, 2011 HDR/Schiff # 11-0774SCS Page 1 A correlation between electrical resistivity and corrosivity toward ferrous metals is (Romanoff, 1989):

Soil Resistivity in ohm-centimeters Corrosivity Category Greater than 10,000 Mildly Corrosive 2,001 to 10,000 Moderately Corrosive 1,001 to 2,000 Corrosive 0 to 1,000 Severely Corrosive

Other soil characteristics that may influence corrosivity towards metals are pH, soluble salt content, soil types, aeration, anaerobic conditions, and site drainage.

Electrical resistivities were in the mildy to moderately corrosive categories with as-received moisture. When saturated, the resistivities were in the moderately to severely corrosive categories. The resistivities dropped considerably with added moisture because the samples were dry as-received.

Soil pH values varied from 7.8 to 8.4. This range is mildly to moderately alkaline (Romanoff, 1989). These values do not particularly increase soil corrosivity.

The soluble salt content of the samples ranged from low to moderate.

The soluble salt content was moderate in the samples from borings B-2@ 10.5', B-4@ 17.5', B- 6 @ 14.5 ', B-9 @ 10 .5', and less in the others. Chloride salts were the predominant constituents. Chloride is particularly corrosive to ferrous metals, and in the higher concentrations measured in the soil samples, chloride can overcome the corrosion inhibiting effect of concrete on reinforcing steel.

Ammonium was detected in low concentrations. The nitrate concentration was high enough to be deleterious to copper.

Tests were not made for sulfide and negative oxidation-reduction (redox) potential because these samples did not exhibit characteristics typically associated with anaerobic conditions.

This soil is classified as severely corrosive to ferrous metals, aggressive to copper, and aggressive with respect to exposure of reinforcing steel to the migration of chloride.

CONCLUSIONS

This soil is classified as severely corrosive to ferrous metals, aggressive to copper, and aggressive with respect to exposure of reinforcing steel to the migration of chloride.

Based on this investigation, reinforced construction materials are satisfactory when following the material recommendations outlined in this report.

Inland Foundation Engineering, Inc . August 17 , 2011 HDR/Schiff # 11-0774SCS Page 2 RECOMMENDATIONS

Reinforced Concrete Pipe Implement all the following measures.

1. Based on this investigation, reinforced concrete pipe used for the proposed alignment must follow the recommendations provided in concrete structures section.

2. To prevent dissimilar metal conosion cells electrically isolate the storm drain per NACE Standard SP0286 from all structures and facilities. Insulated joints should be placed above grade or in vaults where possible. WrillJ all buried insulators with wax tape per A WW A C217.

3. Prevent contact between the steel pipe and concrete and/or reinforcing steel, such as at wall penetrations and thrust blocks, with such items as plastic sleeves, rubber seals, or 20 mil plastic tape.

4. Buried steel and iron pipe and fittings in appurtenances should be cement-mortar coated or concrete or cement slurry encased where possible. Otherwise, they should be wrapped with wax tape per A WW A Standard C-217

5. To insure that conosion control is properly designed, preliminary construction drawings should be reviewed by a qualified conosion engineer.

All Pipe

1. On all pipes, appurtenances, and fittings not protected by cathodic protection or encased in concrete, coat pipe specials such as valves, bolts, flange joints, joint harnesses, and flexible couplings with wax tape per A WWA C217 after assembly.

2. Where metallic pipelines penetrate concrete structures such as building floors, vault walls, and thrust blocks use plastic sleeves, rubber seals, or other dielectric material to prevent pipe contact with the concrete and reinforcing steel.

Concrete Structures 1. From a conosion standpoint, any type of cement may be used for concrete structures and 12 3 4 pipe because the sulfate concentration is negligible, 0 to 0.1 percent. • • •

1 1997 Uniform Building Code (UBC) Table 19-A-4 2 20061nternational Building Code (IBC) which refers to American Concrete Institute (ACI-318) Table 4.3.1 3 2006 International Residential Code (IRC) which refers to American Concrete Institute (ACI-318) Table 4.3.1 4 2007 California Building Code (CBC) which refers to American Concrete Institute (ACI-318) Table 4.3.1

Inland Foundation Engineering, Inc. August 17, 2011 HDR/Schiff # 11 - 0774SCS Page 3 2. Chloride levels were measured at levels5 where additional protective measures are required for concrete. Protect steel and iron embedded in concrete structures and pipe from chloride attack. This applies to such items as reinforcing steel and anchor bolts but not post-tensioning strands and anchors. The protection could be one or a combination of the following: a. Protective Concrete - A concrete mix designed to protect embedded steel and iron that should be based on the following parameters: I) a chloride content of 500 ppm in the soil; 2) the desired service life; and 3) concrete cover. A protective concrete mix may include a corrosion inhibitor admixture and/or silica fume admixture. b. Waterproof Concrete - Waterproofing for concrete could be a gravel capillary break under the concrete, a waterproof membrane, and/or a liquid applied waterproof barrier coating such as Grace Preprufe products®. Visqueen, similar rolled barriers, or bentonite-based membranes are not viable waterproofing systems, from a corrosion standpoint. c. Coat Embedded Metal - A coating for embedded steel and iron could be an epoxy coating applied to the metal. Purple fusion bonded epoxy (FBE) (ASTM A934) intended for prefabricated reinforcing steel reinforcing steel is suitable. The green flexible FBE (ASTM A 775) is not recommended. d. Cathodic Protection - Cathodic protection is most practical for pipelines and must be designed for each application. The amount of cathodic protection current needed can be minimized by coating the steel or iron.

CLOSURE

Our services have been performed with the usual thoroughness and competence of the engineering profession. No other warranty or representation, either expressed or implied, is included or intended.

Please call if you have any questions.

Respectfully Submitted, HDR ENGINEERING, INC. c~'/)~~~ <4~· Leobardo Solis ~

5 Design Manual 303: Concrete Cylinder Pipe. Ameron. p. 65

Inland Foundation Engineering, Inc. August 17, 2011 HDR I Schiff I 1-0554SC S 11-077 4SCS Page 4 WORKS CITED

A WWA. (C105-05). "American National Standard for Polyethylene Encasement for Ductile-Iron Pipe Systems". Denver, CO: www.awwa.org/.

Romanoff, M. (1989). Underground Corrosion, National Bureau of Standards (NBS) Circular 579. Houston, TX, United States of America: Reprinted by NACE.

Inland Foundation Engineering, Inc. August 17, 2011 HDR/Schiff # 11-0774SCS Page 5 lil~ SCHIFF www.hdrinc.com Corrosion Control and Condition Assessment (C3A) Department fl Table 1 - Laboratory Tests on Soil Samples

Inland Foundation Engineering, Inc. n Hemet MDP Line C-Stage 4 (Whittier Avenue) Your #W175-068, HDR1Schiff#ll-0774SCS 4-Aug-11 1

Sample ID B-1 B-2 B-3 B-4 5.5' @ 10.5' @ 19.5' @ 17.5'

Resistivity Units r 1 as-received olnn-cm 32,400 7,200 80,000 12,000 35,200 saturated olnn-cm 5,600 1,080 6,000 1,160 1,840 f l pH 8.4 8.4 8.2 7.9 8.3 Electrical 1 Conductivity mS/cm 0.10 0.32 0.08 0.21 0.18 Chemical Analyses Cations calcium ci+ mg/kg 100 105 56 123 47 magnesium Mg2+ mg/kg 5.4 13 9.0 19 4.0 sodium Na 1+ mg/kg 78 247 29 42 147 potassium KI + mg/kg 8.2 16 13 21 15 Anions carbonate co/ mg/kg 9.0 9.0 6.0 ND ND 1 bicarbonate HC03 - mg/kg 263 183 105 134 162 fluoride FI- mg/kg 5.5 14 2.0 2.2 5.5 1 Cl - J chloride mg/kg 3.2 214 26 221 177 l sulfate so/ mg/kg 30 140 39 46 11 phosphate PO/ mg/kg ND ND ND ND ND

Other Tests ammonium NH4I + mg/kg ND ND 1.9 1.3 ND nitrate NOt mg/kg 5.3 130 1.4 1.6 ND sulfide sz- qual na na na na na Redox mV na na na na na

Electrical conductivity in millisiemens/cm and chemical analysis were made on a 1:5 soil-to-water extract. mg/kg = milligrams per kilogram (parts per million) of dry soil. Redox= oxidation-reduction potential in millivolts ND = not detected na = not analyzed

431 West Baseline Road · Claremont CA 91711 Phone: 909.626.0967 · Fax: 909.626.3316 Pagel of2 l SCHIFF l liR www.hdrinc.com Corrosion Control and Condition Assessment (C3A) Department II Table 1 - Laboratory Tests on Soil Samples

r I Inland Foundation Engineering, Inc. I i Hemet MDP Line C-Stage 4 (Whittier Avenue) Your #W175-068, HDRISchiff#ll-0774SCS 4-Aug-11

Sample ID B-8 B-9 l I @ 12.5' @ 10.5'

[ ~ Resistivity Units as-received ohm-em 12,000 3,840 11,200 5,600 16,800 saturated ohm-em 680 1,880 1,120 1,160 1,160 f l pH 7.8 8.2 7.8 7.9 8.0 Electrical I 1 Conductivity mS/cm 0.38 0.19 0.28 0.42 0.28

Chemical Analyses Cations calcium Ca2+ mg/kg 164 89 126 240 165 magnesium Mgz+ mg/kg 34 15 19 32 24 sodium Na1+ mg/kg 141 124 123 96 81 I potassium K'+ mg/kg 25 19 18 22 8.6 Anions carbonate cot mg/kg ND 21 ND ND ND I I 1 bicarbonate HC03 - mg/kg 189 167 125 186 232 fluoride F'- mg/kg 5.8 5.8 4.6 6.7 5.4 t1 chloride Cl'- mg/kg 468 73 268 454 181 sulfate sot mg/kg 41 129 150 153 220 phosphate PO/ mg/kg ND ND ND ND ND

Other Tests ammonium NH4'+ mg/kg 1.1 ND 1.5 0.9 1.0 nitrate Not mg/kg 7.6 84 4.2 11 21 sulfide sz- qual na na na na na I Redox mV na na na na na Electrical conductivity in millisiemens/cm and chemical analysis were made on a 1:5 soil-to-water extract. mg/kg = milligrams per kilogram (parts per million) of dry soil. J Redox = oxidation-reduction potential in millivolts ND = not detected na = not analyzed

431 West Baseline Road · Claremont, CA 91711 Phone: 909.626.0967 · Fax: 909.626.3316 Page 2 of 2