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07-2053 (CSCS) Geotechnical UpdateKOMAR INVESTMENTS 10144 CENTRAL AVENUE CHINO, CALIFORNIA 91710 I DESIGN LEVEL GEOTECHNICAL ENGINEERING REPORT LA QUINTA COMMERCIAL PARK SWC HIGHWAY 111 AND JEFFERSON STREET LA QUINTA, CALIFORNIA March 22, 2006 • i © 2006 Earth Systems Southwest Unauthorized use or copying of this document is strictly prohibited without the express written consent of Earth Systems Southwest. File No:: 07762-02 06-03-821 J�% Earth Systems 1� Southwest 79-811B Country Club Drive Bermuda Dunes, CA 92203 (760)345-1588 (800)924-7015 FAX (760) 345-7315 March 22, 2006 Komar Investments 10144 Central Avenue Chino, California 91710 Attention:. Mr. Zaven Hanessian Project: Proposed La Quinta Commercial Park SWC Highway 111 and Jefferson Street La Quinta, California Subject: DESIGN LEVEL GEOTECHNICAL ENGINEERING REPORT Dear Mr. Hanessian: File No.: 07762-02 06-03-821 We take pleasure to present this Design Level Geotechnical Engineering Report prepared for the proposed La Quinta Commercial Park to be located near the southwest corner of Highway 111 and Jefferson Street in the City of La Quinta, California. This report presents our findings and recommendations for site grading and foundation design, incorporating the tentative information supplied to our office. This report should stand as a whole, and no part of the report should be excerpted or used to the exclusion of any other part. This report completes our scope of services in accordance with our agreement, dated February 9, 2006. Other services that may be required, such as plan review and grading observation are additional services and will be billed according to the Fee Schedule in effect at the time services are provided. Unless requested in writing, the client is responsible to distribute this report to the appropriate governing agency or other members of the design team. We appreciate the opportunity to provide our professional services. Please contact our office if there are any questions or comments concerning this report or its recommendations. Respectfully submitted, EARTH SYSTEMS SOUTHWEST Craig S. Hill 0 CE 38234 CE 38234 EXP. 3/311 7 SER/csh/ajf Distribution: 10/K o ents 1/RC File 2BD File TABLE OF CONTENTS Page Section1 INTRODUCTION..................................................................................................1 1.1 Project Description..................................................................................................1 1.2 Site Description........................................................................................................1 1.3 Purpose and Scope of Work.....................................:...............................................1 Section 2 METHODS OF INVESTIGATION.....................................................................3 2.1 Field Exploration..................................................:.:................................................3 2.2 Laboratory Testing...................................................................................................3 Section3 DISCUSSION..........................................................................................................4 3.1 Soil Conditions........................................................................................................4 3.2 Groundwater............................................................................................................4 3.3' Geologic Setting......................................................................................................4 3.4 Geologic Hazards.....................................................................................................5 3.4.1 Seismic Hazards...........................................................................................5 3.4.2 Secondary Hazards.......................................................................................6 3.4.3 Site Acceleration and Seismic Coefficients.................................................7 Section4 CONCLUSIONS....................................................................................................9 Section 5 RECOMMENDATIONS.....................................................................................10 SITE DEVELOPMENT AND GRADING......................................................................10 5.1 Site Development - Grading..................................................................................10 5.2 Excavations and Utility Trenches..........................................................................11 5.3 Slope Stability of Graded Slopes...........................................................................11 STRUCTURES.................................................................................................................12 5.4 Foundations............................................................................................................12 5.5 Slabs-on-Grade......................................................................................................13 5.6 Retaining Walls.......................................................................................................14 5.7 Mitigation of Soil Corrosivity on Concrete...........................................................15 5.8 Seismic Design Criteria.........................................................................................15 5.9 Pavements..........................................:....................................................................16 Section 6 LIMITATIONS AND ADDITIONAL SERVICES..........................................17 6.1 Uniformity of Conditions and Limitations............................................................17 6.2 Additional Services................................................................................................18 REFERENCES...............................................................................................................19 APPENDIX A Figure 1 - Vicinity Map Figure 2 - Boring Location Map Table 1 Fault Parameters Logs of Borings APPENDIX B . Laboratory Test Results EARTH SYSTEMS SOUTHWEST March 22, 2006 - 1 - File No.: 07762-02 06-03-821 Section 1 , INTRODUCTION 1.1 Project Description This Geotechnical Engineering Report has been prepared for the proposed La Quinta Commercial Park to be located near the southwest corner of the intersection of Highway 111 and Jefferson Street in the City of La Quinta, California. The proposed development will include one major retail anchor nine other commercial structures. This report is limited to the nine commercial structures and does not include the major anchor (Costco). We understand that the proposed structure will be of wood frame and masonry block type construction and will be supported by conventional shallow continuous or pad footings. Building A will have a loading dock along the east side of the proposed building. Site development will include site grading, building pad preparation, underground utility installation, street improvements and parking lot construction, and concrete driveway and sidewalk placement. We used maximum column loads of 75 kip column loads and 2 kips per linear foot. All loading is assumed to be dead plus actual live load. The preliminary design loading was assumed, if actual structural loading is to exceed these assumed values, we might need to reevaluate the given recommendations. 1.2 Site Description The proposed commercial park is to be constructed on the site. The site location is shown on Figure 1 in Appendix A. The project site presently consists of fairly flat desert with a light to moderate cover of desert brush. Some grading activity has taken place along the existing La Quinta Evacuation Channel and along Highway 111. There are existing underground utilities along Highway 111 and along a portion of the La Quinta Evacuation Channel. Other utility lines may exist on the subject site this condition should be verified by the contractor prior to construction. The site is rectangular in shape and is bounded by Highway 111 to the north, the La Quinta Evacuation Channel to the southeast and private land to the south and west. The shopping center continues to the east, however is located in the City of Indio and is reported under separate cover. 1.3 Purpose and Scope of Work The purpose for our services was to evaluate the site soil conditions and to provide professional opinions and recommendations regarding the proposed development of the site. The scope of work included the following: ➢ A general reconnaissance of the site. ➢ Shallow subsurface exploration by drilling 10 -exploratory borings drilled in 2000 and 5 supplemental borings drilled on February 27 and March 1, 2006 to depths ranging from 6.5 to 51.5 feet below existing grades..: EARTH SYSTEMS SOUTHWEST March 22, 2006 - 2 - File No.: 07762-02 06-03-821 ➢ Laboratory testing of selected soil samples obtained from the exploratory borings. ➢ Review of selected published technical literature pertaining to the site and previous ` geotechnical reports prepared for site in the vicinity of the subject site. ➢ Engineering analysis and evaluation of the acquired data from the exploration and testing programs. A summary of our findings and recommendations in this written report. This report contains the following: ➢ Discussions on subsurface soil and groundwater conditions. ➢ ' Discussions on regional and local geologic conditions. ➢ Discussions on geologic and seismic hazards. ➢ Graphic and tabulated results of laboratory tests and field studies. ➢ Recommendations regarding: • Site development and grading criteria, • Excavation conditions and buried utility installations, • Structure foundation type and design, • Allowable foundation bearing capacity and expected total and differential settlements, • Concrete slabs -on -grade, • Lateral earth pressures and coefficients, Mitigation of the potential corrosivity of site soils to concrete and steel reinforcement, • Seismic design parameters, • Pavement structural sections. Not Contained in This Report: Although available through Earth Systems Southwest, the current scope of our services does not include: ➢ A corrosive study to determine cathodic protection of concrete or buried pipes. ➢ An environmental assessment. ➢ Investigation for the presence or absence of wetlands, hazardous or toxic materials in the soil, surface water, groundwater, or air on, below, or adjacent to the subject property. I EARTH SYSTEMS SOUTHWEST March 22, 2006 - 3 - File No.: 07762-02 06-03-821 Section 2 METHODS OF INVESTIGATION 2.1 Field Exploration A total of fifteen exploratory borings were drilled to depths ranging from 6.5 to 51.5 feet below the existing ground surface to observe the soil profile and- to obtain samples for laboratory testing. The borings were drilled on May 23, 2000, February 27, and March 1, 2006 using 8- inch outside diameter hollow -stem augers. The borings drilled in 2000 were accomplished using a Mobile B61 truck -mounted drilling rig, while the borings drilled in 2006 were accomplished using a CME 75. The boring locations are shown on the boring location map, Figure 2, in Appendix A. The locations shown are approximate, established by pacing and sighting from existing topographic features. Samples were obtained within the test borings using .a Standard Penetration (SPT) sampler (ASTM D 1586) and a Modified California (MC) ring sampler (ASTM D 3550 with shoe similar to ASTM D 1586). The SPT sampler has a 2 -inch outside diameter and a 1.38 -inch inside diameter. The MC sampler has a 3 -inch outside diameter and a 2.37 -inch inside diameter. Sampling using the Mobile B61 and CME 75 were obtained by either driving a sampler with a 140 -pound downhole hammer dropping 30 inches or an automatic hammer dropping 30 inches, both in general accordance with ASTM D 1586. Recovered soil samples were sealed in containers and returned to the laboratory. Bulk samples were also obtained from auger cuttings, representing a mixture of soils encountered at the depths noted. The final logs of the borings represent our interpretation of the contents of the field logs and the results of laboratory testing performed on the samples obtained during the subsurface investigation. The final logs are included in Appendix A of this report. The stratification lines represent the approximate boundaries between soil types although the transitions, however, may be gradational. 2.2 Laboratory Testing Samples were reviewed along with field logs to select those that would be analyzed further. Those selected for laboratory testing include soils that would be exposed and used during grading, and those deemed to be within the influence of the proposed structure. Test results are presented in graphic and tabular form in Appendix B of this report. The tests were conducted in general accordance with the procedures of the American Society for Testing and Materials (ASTM) or other standardized methods as referenced below. Our testing program consisted of the following: ➢ In-situ Moisture Content and Unit Dry Weight for the ring samples (ASTM D 2937). ➢ Maximum density tests were performed to evaluate the moisture -density relationship of typical soils encountered (ASTM D 1557-91). ➢ Particle Size Analysis (ASTM D 422) to classify and evaluate soil composition. The gradation characteristics of selected samples were made by hydrometer and sieve analysis procedures. ➢ Consolidation (Collapse Potential) (ASTM D 2435 and D5333) to evaluate the compressibility and hydroconsolidation (collapse) potential of the soil. ➢ Chemical Analyses (Soluble .Sulfates & Chlorides, pH, and Electrical Resistivity) to evaluate the corrosivity of the soil on concrete and steel. EARTH SYSTEMS SOUTHWEST March 22, 2006 - 4 - File No.: 07762-02 06-03-821 Section 3 DISCUSSION 3.1 Soil Conditions The field exploration indicates that site soils consist primarily of silty sand (SM) and sandy silt (ML). Some of the silty sand layers consist of thin laminates of silt and are interbedded with poorly graded sand, however as a mixture result in silty sand classification. The boring logs provided in Appendix A include more detailed descriptions of the soils encountered. The soils are visually classified to be in the very low expansion category in accordance with Table 18A -I -B of the Uniform Building Code. In and climatic regions, granular soils may have a potential to collapse upon wetting. Collapse (hydroconsolidation) may occur when the soluble cements (carbonates) in the soil matrix dissolve, causing the soil to densify from its loose configuration from deposition. Consolidation tests indicate 1.6 to 2.5% collapse upon inundation and are considered -a moderate site risk. The hydroconsolidation potential is commonly mitigated by recompaction of a zone beneath building pads. The site lies within a recognized blow sand hazard area. Fine particulate matter (PM,o) can create an air quality hazard if dust is blowing. Watering the surface, planting grass or landscaping, or hardscape normally mitigates this hazard. 3.2 Groundwater Free groundwater was not encountered in the borings during exploration. The depth to groundwater in the area is believed to be about 136 feet based on nearby 1999 water well data obtained from the Coachella Valley Water District.. However, there is uncertainty in the accuracy of short-term water level measurements. Groundwater levels may fluctuate with precipitation, irrigation, drainage, regional pumping from wells, and site grading. Groundwater should not be a factor in design or construction at this site. 3.3 Geologic Setting Regional Geology: The site lies within the Coachella Valley, a part of the Colorado Desert geomorphic province. A significant feature within the Colorado Desert geomorphic province is the Salton Trough. The Salton Trough is a large northwest -trending structural depression that extends from San Gorgonio Pass, approximately 180 miles to the Gulf of California. Much of this depression in the area of the Salton Sea is below sea level. The Coachella Valley forms the northerly portion of the Salton Trough. The Coachella Valley contains a thick sequence of sedimentary deposits that are Miocene to recent in age. Mountains surrounding the Coachella Valley include the Little San Bernardino Mountains on the northeast, foothills of the San Bernardino Mountains on the northwest, and the San Jacinto and Santa Rosa Mountains on the southwest. These mountains expose primarily Precambrian metamorphic and Mesozoic granitic rocks. .The San Andreas.Fault zone within the Coachella Valley consists of EARTH SYSTEMS SOUTHWEST March 22, 2006 - 5 - File No.: 07762-02 06-03-821 the Garnet Hill Fault, the Banning Fault, and the Mission Creek Fault that traverse along the northeast margin of the valley. Local Geology: The project site is located approximately '/o mile south of the Whitewater River channel in the southeast portion of the Coachella Valley. The sediments within the valley consist of fine to coarse-grained sands with interbedded clays, silts, gravels, and cobbles of aeolian and alluvial origin. The depth to crystalline basement rock beneath the site is estimated to be in excess of 2000 feet (Envicom, 1976). 3.4 Geologic Hazards Geologic hazards that may affect the region -.include seismic hazards (surface fault rupture, ground shaking, soil liquefaction, and other secondary earthquake -related hazards), slope instability, flooding, ground subsidence, and erosion. A discussion follows on the specific hazards to this site. 3.4.1 Seismic Hazards Seismic Sources: Our research of regional faulting indicates that several active faults or seismic zones lie within 62 miles (100 kilometers) of the project site as shown on Table 1 and Figure 4 in Appendix A. The primary seismic hazard to the site is strong groundshaking from earthquakes along the San Andreas and San Jacinto Faults. The Maximum Magnitude Earthquake (Mmax) listed is from published geologic information available for each fault (CDMG, 1996). The Mmax corresponds to the maximum earthquake believed to be tectonically possible. Surface Fault Rupture: The 'project site does not lie within a currently delineated State of California, Alquist-Priolo Earthquake Fault Zone (Hart, 1994). Well -delineated fault lines cross through this region as shown on California Division of Mines and Geology (CDMG) maps (Jennings, 1994). Therefore, active fault rupture is unlikely to occur at the project site. While fault rupture would most likely occur along previously established fault traces, future fault rupture could occur at other locations. Historic Seismicity: Six historic seismic events (5.9 M or greater) have significantly affected the Coachella Valley this century. They are as follows: • Desert Hot Springs Earthquake - On December 4, 1948, a magnitude 6.5 ML (6.OMW) earthquake occurred east of Desert Hot Springs. This event was strongly felt in the Palm Springs area. • Palm Springs Earthquake - A magnitude 5.9 ML (6.2MW) earthquake occurred on July 8, 1986 in the Painted Hills causing minor surface creep of the Banning segment of the San Andreas Fault. This event was strongly felt in the Palm'Springs area and caused structural damage, as well as injuries. • Joshua Tree Earthquake - On April 22, 1992, a magnitude 6.1 ML (6.1Mw) earthquake occurred in the mountains 9 miles east of Desert Hot Springs. Structural damage and minor injuries occurred in the Palm Springs area as a result of this earthquake. • Landers & Big Bear Earthquakes- Early on June 28, 1992, a magnitude 7.5 Ms (7.3MW) earthquake occurred near Landers, the largest seismic event in Southern California for 40 years. Surface rupture occurred just south of the town of Yucca Valley and extended some 43 miles toward Barstow. About three hours later, a magnitude 6.6 Ms (6.4MW) earthquake occurred near Big Bear Lake. No significant structural damage from these earthquakes was reported in the Palm Springs area. EARTH SYSTEMS SOUTHWEST March 22, 2006 - 6 - File No.: 07762-02 06-03-821 • Hector Mine Earthquake - On October 16, 1999, a magnitude 7.1MW earthquake occurred on the Lavic Lake and Bullion Mountain Faults north of 29 Palms. This event while widely felt, no significant structural damage has been reported in the Coachella Valley. Seismic Risk: While accurate earthquake predictions are not possible, various agencies have conducted statistical risk analyses. In 1996, the California. Division of Mines and Geology (CDMG) and the United States Geological Survey (USGS) completed the latest generation of probabilistic seismic hazard maps for use in the 1997 UBC. We have used these maps in our evaluation of the seismic risk at the site. The Working Group of California Earthquake Probabilities (WGCEP, 1995) estimated a 22% conditional probability that a magnitude 7 or greater earthquake may occur between 1994 to 2024 along the Coachella segment of the San Andreas fault. The primary seismic risk at the site is a potential earthquake along the San Andreas. Fault. Geologists believe that the San Andreas Fault has characteristic earthquakes that result from rupture of each fault segment. The estimated characteristic earthquake is magnitude 7.4 for the Southern Segment of the fault. This segment has the longest elapsed time since rupture than any other portion of the San Andreas Fault. The last rupture occurred about 1690 AD, based on dating by the USGS near Indio (WGCEP, 1995). This segment has also ruptured on about 1020, 1300, and 1450 AD, with an average recurrence interval of about 220 years. The San Andreas Fault may rupture in multiple segments producing a higher magnitude earthquake. Recent paleoseismic studies suggest that the San Bernardino Mountain Segment to the north and the Coachella Segment may have both ruptured together in 1450 and 1690 AD (WGCEP, 1995). 3.4.2 Secondary Hazards Secondary seismic hazards related to ground shaking include soil- liquefaction, ground deformation, areal subsidence, tsunamis, and seiches. The site is far inland so the hazard from tsunamis is non-existent. At the present time, no water storage reservoirs are located in the immediate vicinity of the site. Therefore, hazards from seiches are considered negligible at this time. Soil Liquefaction: Liquefaction is the loss of soil strength from sudden shock (usually earthquake shaking), causing the soil to become a fluid mass. In general, for the effects of liquefaction to be manifested at the surface, groundwater levels must be within 50 feet of the ground surface and the soils within the saturated zone must also be susceptible to liquefaction. The potential for liquefaction to occur at this site is considered negligible because the depth of groundwater beneath the site exceeds 50 feet. No free groundwater was encountered in our exploratory borings. In addition, the project does not lie within the Riverside County. liquefaction study zone. Ground Deformation and Subsidence: Non -tectonic ground deformation consists of cracking of the ground with little to no displacement. This type of deformation is generally associated with differential shaking of two or more geologic units with differing engineering characteristics. Ground deformation may also be caused by liquefaction. As the site is relatively flat with consistent geologic material, and has a low potential for liquefaction; the potential for ground deformation is also considered to be low. 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Reference Seismic Zone: 4 Figure 16-2 Seismic Zone Factor, Z: 0.4 Table 16-I Soil Profile Type: SD Table 16-J Seismic Source Type: A Table 16-U Closest Distance to Known Seismic Source:; 8 km = 5 miles (San Andreas fault) Near Source Factor, Na: -- 1.08 Table 16-S Near Source Factor, Nv: 1.36 Table 16-T Seismic Coefficient, Ca: 0.48 = 0.44Na Table 16-Q Seismic Coefficient, Cv: 0.87 = 0.64Nv Table 16-R Seismic Hazard Zones: The site does not lie within a liquefaction, landslide, or fault rupture hazard area or zone established by the 2002 Riverside County General Plan. This part of Riverside County has not yet been mapped by the California Seismic Hazard Mapping Act (Ca. PRC 2690 to 2699). r EARTH SYSTEMS SOUTHWEST March 22, 2006 - 9 - File No.: 07762-02 06-03-821 Section 4 CONCLUSIONS The following is a summary of our conclusions and professional opinions based on the data obtained from a review of selected technical literature and the site evaluation. ➢ The primary geologic hazard relative to site development is. severe ground shaking from earthquakes originating on nearby faults. In our. opinion, a major seismic event originating on the local segment of the San Andreas Fault zone would be the most likely cause of significant earthquake activity at the site within the estimated design life of the proposed development. ➢ The project site is in seismic Zone 4 as defined in the Uniform Building Code. A qualified professional who is aware of the site seismic setting should design any permanent structure constructed on the site. ➢ Ground subsidence from seismic events or hydroconsolidation is a potential hazard in the Coachella Valley area. Adherence to the following grading and structural recommendations should reduce potential settlement problems from seismic forces, heavy rainfall or irrigation, flooding, and the weight of the intended structures. ➢ The soils are susceptible to wind and water erosion. Preventative measures to minimize seasonal flooding and erosion should be incorporated into site grading plans. Dust control should also be implemented during construction. ➢ Other geologic hazards including ground rupture, liquefaction, seismically induced flooding, and landslides are considered moderate on this site. ➢ The upper soils were found to range from loose to dense. In our opinion, the soils within the building areas will require over excavation and recompaction to improve bearing capacity and reduce settlement from static loading. Soils should be readily cut by normal grading equipment. Please refer to Section 5, "Site Development and Grading" for specific grading recommendations. ➢ Earth Systems Southwest (ESSW) should provide geotechnical engineering services 'during project design, site development, excavation, grading, and foundation construction phases of the work. This is to observe compliance with the design concepts, specifications, and recommendations, and to allow design changes in the event that subsurface conditions differ from those anticipated prior to the start of construction. ➢ Plans and specifications should be provided to ESSW prior to grading. Plans should include the grading plans, foundation plans, and foundation details. Preferably, structural loads should be shown on the foundation plans. EARTH SYSTEMS SOUTHWEST March 22, 2066 _10- File No.: 07762-02 06-03-921 Section 5 RECOMMENDATIONS SITE DEVELOPMENT AND GRADING 5.1 Site Development - Grading A representative of ESSW should observe site grading and the bottom of excavations prior to placing fill. Local variations in soil conditions may warrant increasing the depth of recompaction and over -excavation. Clearing and Grubbing: Prior to site grading_ existing vegetation, large roots, and abandoned underground utilities or other deleterious material should be removed from the proposed building and pavement areas. The surface should be stripped of organic growth and removed from the construction area. - Areas disturbed during clearing operations should be properly backfilled and compacted as described below. Pad Preparation (Buildings A -I): Because of the relatively nori-uniform nature of the soils in the vicinity of these buildings, we recommend recompaction of the proposed bearing soils. The existing surface soils within the building pad areas should be over -excavated to 4 feet below existing ' grade (of in the case of areas of cut, a minimum of 3 -feet below the bottom of the deepest footing level). The over -excavation should extend for 20 -feet beyond the outer edge of exterior footings. This distance outside the perimeter will allow for minor shifting or reconfiguring of the building footprint and to incorporate perimeter sidewalks. Building A will have a loading dock located along the east side of the proposed building. The over excavation in this area should be to a depth of 3 -feet below the bottom of the proposed foundations to a distance of 10 feet outside the perimeter. The bottom of the over excavations should be scarified; moisture conditioned, and recompacted to at least 90% relative compaction (ASTM D 1557) for an additional depth of 12 -inches. Moisture penetration to near optimum moisture should extend to at least the upper 5 -feet of existing grade. Site Walls: Site masonry walls that are not structurally connected to buildings should be over - excavated 24 -inches below existing or a minimum of 12 -inches below the footing. level (whichever is lower). The over -excavation should extend at least 3 -feet beyond the outer edge of exterior footings except where prohibited due to the site property line in which case the over - excavation should be to at least the edge of the footing. The bottom of the sub -excavation should be scarified; moisture conditioned, and recompacted to at least 90 % relative compaction (ASTM D 1557) for an additional depth of 12 -inches. Subgrade Preparation: In areas to receive fill, pavements, or hardscape, the ground surface should be scarified; moisture conditioned, and compacted to at least 90% relative compaction (ASTM D 1557) for a depth of 12 inches below finished subgrades. Compaction should be verified by testing. Engineered Fill Soils: The native soil is suitable for use as engineered fill and utility trench backfill. The native soil should be placed in maximum 8 -inch lifts (loose) and compacted to at least 90% relative compaction (ASTM D 1557) near its optimum moisture content. Compaction EARTH SYSTEMS SOUTHWEST March 22, 2006 - 11 - File No.: 07762-02 06-03-821 should be verified by testing. All rocks larger than 6 inches in greatest dimension should be removed from fill or backfill material. Imported fill soils (if required) should be non -expansive, granular soils .meeting the USCS classifications of SM, SP -SM, or *SW -SM with a maximum rock size of 3 inches and 5 to 35% passing the No. 200 sieve. The geotechnical engineer should evaluate the import fill soils before hauling to the site. However, because of the potential variations within the borrow source, import soil will not prequalified by ESSW. The imported fill should be placed in lifts no greater than 8 inches in loose thickness and compacted to at least 90% relative compaction (ASTM D 1557) near optimum moisture content. Shrinkage: The shrinkage factor for earthwork -is expected to range from 15 to 20 percent (with some areas over 30%) for the upper excavated or scarified site soils. This estimate is based on compactive effort to achieve an average relative compaction of about 92% and may vary with contractor methods. Subsidence is estimated to be less than 0.2 feet. Losses from site clearing and removal of existing site improvements may affect earthwork quantity calculations and should be considered. Site Drainage: Positive drainage should be maintained away from the structures (5% for 5 .feet minimum) to prevent ponding and subsequent saturation of the foundation soils. Gutters and downspouts should be considered as a means to convey water away from foundations if adequate drainage is not provided. Drainage should be maintained for paved areas. Water should not pond on or near paved areas. 5.2 Excavations and Utility Trenches Excavations should be made in accordance with CalOSHA requirements. Our site exploration and knowledge of the general area indicates there is a potential for caving of site excavations (utilities, footings, etc.). Excavations within sandy soil should be kept moist, but not saturated, to reduce the potential of caving or sloughing. Where excavations over 4 feet deep are planned, lateral bracing or appropriate cut slopes of 1.5:1 (horizontal:vertical) should be provided. No surcharge loads from stockpiled soils or construction materials should be allowed within a horizontal distance measured from the top of the excavation slope and equal to the depth of the excavation. Utility Trenches: Backfill of utilities within roads or public right-of-ways should be placed in conformance with the requirements of the governing agency (water district, public works department, etc.). Utility trench backfill within private property should be placed in conformance with the provisions of this report. In general, service lines extending inside of property may be backfilled with native soils compacted to a minimum of 90% relative compaction. Backfill operations should be observed and tested to monitor compliance with these recommendations. 5.3 Slope Stability of Graded Slopes Unprotected, permanent graded slopes should not be steeper than 3:1 (horizontal: vertical) to reduce wind and rain erosion. Protected slopes with ground cover may be as steep as 2:1. EARTH SYSTEMS SOUTHWEST I March 22, 2006 -12- File No.: 07762-02 06-03-821 However, maintenance with motorized equipment may not be possible at this inclination. Fill slopes should be overfilled and trimmed back to competent material. STRUCTURES In our professional opinion, the structure foundation can be supported on shallow foundations bearing on a zone of properly prepared and compacted soils placed as recommended in Section 5.1. The recommendations that follow are based on very low expansion category soils. 5.4 Foundations Footing design of widths, depths, and reinforcing are the responsibility of the Structural Engineer, considering the structural loading and the geotechnical parameters given in this report. A minimum footing depth of 18 inches below lowest adjacent grade should be maintained. A representative of ESSW should observe foundation excavations prior to placement of reinforcing steel or concrete. Any loose soil or construction debris should be removed from footing excavations prior to placement of concrete. Conventional Spread Foundations: Allowable soil bearing pressures are given below for foundations bearing on recompacted soils as described in Section 5.1. Allowable bearing pressures are net (weight of footing and soil surcharge may be neglected). ➢ Continuous wall foundations, 12 -inch minimum width and 18 inches below grade: 1800 psf for dead plus design live loads Allowable increases of 300 psf per each foot of additional footing width and 300 psf for each additional 0.5 foot of footing depth may be used up to a maximum value of 3000 psf. ➢ Isolated pad foundations, 2 x 2 foot minimum in plan and 18 inches below grade: 2000 psf for dead plus design live loads Allowable increases of 200 psf per each foot of additional footing width and 350 psf for each additional 0.5 foot of footing depth may be used up to a maximum value of 3000 psf. A one-third ('/3) increase in the bearing pressure may be used when calculating resistance to wind or seismic loads. The allowable bearing values indicated are based on the anticipated maximum loads stated in Section 1.1 of this report. If the anticipated loads exceed these values, the geotechnical engineer must reevaluate the allowable bearing values and the grading requirements. Minimum reinforcement for continuous wall footings should be two, No. 4 steel reinforcing bars, placed near the top and the bottom of the footing. This reinforcing is not intended to supersede any structural requirements provided by the structural engineer. Expected Settlement: Estimated total static settlement should be less than 1 inch, based on footings founded on firm soils as recommended. Differential settlement between exterior -and interior bearing members should be less than %2 inch, expressed in a post -construction angular distortion ratio of 1:480 or less. EARTH SYSTEMS SOUTHWEST March 22, 2006 - 13 - File No.: 07762-02 06-03-821 Frictional and Lateral Coefficients: Lateral loads may be resisted by soil friction on the base of foundations and by passiveresistance of the soils acting on foundation walls. An allowable coefficient of friction of 0.35 of dead load may be used. An allowable passive equivalent fluid pressure of 250 pcf may also be used. These values include a factor of safety of 1.5. Passive resistance and frictional resistance may be used in combination if -the friction coefficient is reduced to 0.23 of dead load forces. A one-third (1/3) increase in the passive pressure may be used when calculating resistance to wind or seismic loads. Lateral passive resistance is based on the assumption that any required backfill adjacent to foundations is properly compacted. 5.5 Slabs -on -Grade Sub rade: Concrete slabs -on -grade and flatwork should be supported by compacted soil placed in accordance with Section 5.1 of this report. Vapor Retarder: In areas of moisture sensitive floor coverings, an appropriate vapor retarder should be installed to reduce moisture transmission from the subgrade soil to the slab. For these areas, an impermeable membrane (10 -mil thickness) should underlie the floor slabs. The membrane should be covered with 2 inches of sand to help protect it during construction and to aid in concrete curing. The sand should be lightly moistened just prior to placing the concrete. Low -slump concrete should be used to help reduce the potential for concrete shrinkage. The effectiveness of the membrane is dependent upon its quality, the method of overlapping, its protection during construction, and the successful sealing of the membrane around utility lines. The following minimum slab recommendations are intended to address geotechnical concerns such as potential variations of the subgrade and are not to be construed as superseding any structural design. Slab Thicknes's and Reinforcement: Slab thickness and reinforcement of slabs -on -grade are contingent on the recommendations of the structural engineer or architect and the expansion index of the supporting soil. Based upon our findings, a modulus of subgrade reaction of approximately 200 pounds per cubic inch can be used in concrete slab design for the expected very low expansion subgrade. Concrete slabs and flatwork should be a minimum of 4 inches thick (actual, not nominal). We suggest that the concrete slabs be reinforced in accordance with the structural engineer's recommendations. Concrete floor slabs may either be monolithically placed with the foundations or doweled after footing placement. The thickness and reinforcing given are not intended to supersede any structural requirements provided by the structural engineer. The project architect or geotechnical engineer should continually observe all reinforcing steel in slabs during placement of concrete to check for proper location within the slab. Control Joints: Control joints should be provided in all concrete slabs -on -grade at a maximum spacing of 36 times the slab thickness (12 feet maximum on -center, each way) as recommended by American Concrete Institute (ACI) guidelines. All joints should form approximately square patterns to reduce the potential for randomly oriented contraction cracks. Contraction joints in the slabs should be tooled at the time of the pour or saw cut ('/4 of slab depth) within 8 hours of concrete placement. Construction (cold) joints should consist of thickened butt joints with -inch dowels at 18 -inches on center or a thickened keyed joint to resist vertical deflection at EARTH SYSTEMS SOUTHWEST March 22, 2006 -14- File No.: 07762-02 06-03-821 the joint. All construction joints in exterior flatwork should be sealed to reduce the potential of moisture or foreign material intrusion. These procedures will reduce the potential for randomly oriented cracks, but may not prevent them from occurring. Curingand nd Quality Control: The contractor should take precautions to reduce the potential of curling of slabs in this and desert region using proper batching, placement, and curing methods. Curing is highly affected by temperature, wind, and humidity: Quality control procedures may be used, including trial batch mix designs, batch plant inspection, and on-site special inspection and testing. Typically, using 2500 -psi concrete, many of these quality control procedures are not required. 5.6 Retaining Walls The following table presents lateral earth pressures for use in retaining wall design. The values are given as equivalent fluid pressures without surcharge loads or hydrostatic pressure. Lateral Pressures and Sliding Resistance 1 Granular Backfill Passive Pressure 350 pcf -level ground Active Pressure (cantilever walls) 35 pcf - level ground Able to rotate 0.1 % of structure height At -Rest Pressure restrained walls 55 pcf - level ground Dynamic Lateral Earth Pressure 2 Acting at mid height of structure, 23H psf Where H is height of backfill in feet Base Lateral Sliding Resistance Dead load x Coefficient of Friction: 0.50 Notes: 1. These values are ultimate values. A factor of safety of 1.5 should be used in stability analysis except for dynamic earth pressure where a factor of safety of 1.2 is acceptable. 2. Dynamic pressures are based on the Mononobe-Okabe 1929 method, additive to active earth pressure. Walls retaining less than 6 feet of soil need not consider this increased pressure. Upward sloping backfill or surcharge loads from nearby footings can create larger lateral pressures. Should any walls be considered for retaining sloped backfill or placed next to foundations, our office should be contacted for recommended design parameters. Surcharge loads should be considered if they exist within a zone between the face of the wall and a plane projected 45 degrees upward from the base of the wall. The increase in lateral earth pressure should be taken as 35% of the surcharge load within this zone. Retaining walls subjected to traffic loads should include a uniform surcharge load equivalent to at least 2 -feet of native soil. Drainaize: A backdrain or an equivalent system of backfill drainage should be incorporated into the retaining wall design. Our firm can provide construction details when the specific application is determined. Backfill immediately behind the retaining structure should be a free - draining granular material. Waterproofing should be according to the Architect's specifications. Water should not be allowed to pond near the top of the wall. To accomplish this, the final backfill grade should be such that all water is diverted away from the retaining wall. EARTH SYSTEMS SOUTHWEST March 22, 2006 _ -15 - File No.: 07762-02 06-03-821 Backfill Compaction: Compaction on the retained side of the wall within a horizontal distance equal to one wall height should be performed by hand -operated or other lightweight compaction equipment. This is intended to reduce potential locked -in lateral pressures caused by compaction with heavy grading equipment. 5.7. Mitigation of Soil Corrosivity on Concrete Selected chemical analyses for corrosivity were conducted on samples at the project site. The native soils were found to have negligible sulfate ion concentration (68 ppm) and negligible chloride ion concentration (82 ppm). Sulfate ions can attack the cementitious material . in concrete, causing weakening of the cement matrix and eventual deterioration by raveling. Chloride ions can cause corrosion of reinforcing steel. The Uniform Building Code does not require any special provisions for concrete for these low concentrations as tested. Normal concrete mixes may be used. A minimum concrete cover of three (3) inches should be provided around steel reinforcing or embedded components exposed to native soil or landscape water (to 18 inches above grade). Additionally, the concrete should be thoroughly vibrated during placement. Electrical resistivity testing of the soil suggests that the site soils may present a severe potential for metal loss from electrochemical corrosion processes. Corrosion protection of steel can be achieved by using epoxy 'corrosion, inhibitors, asphalt coatings, cathodic protection, or encapsulating with densely consolidated concrete. A qualified corrosion engineer should be consulted regarding mitigation of the corrosive effects of site soils on metals. 5.8 Seismic Design Criteria This site is subject to strong ground shaking due to potential fault movements along the San Andreas and San Jacinto faults. Engineered design and -earthquake-resistant construction increase safety and allow development of seismic areas. The minimum seismic design should comply with the 2001 edition of the California Building Code using the seismic coefficients given in the table below. 2001 CBC Seismic Coefficients for Chapter 16 Seismic Provisions Seismic Zone: 4 Seismic Zone Factor, Z: 0.4 Soil Profile Type: SD Seismic Source Type: A Closest Distance to Known Seismic Source: 8 km = 5 miles Near Source Factor, Na: 1.08 Near Source Factor, Nv: 1.36 Seismic Coefficient, Ca: 0.48 = 0.44Na Seismic Coefficient, Cv: 0.87 = 0.64Nv EARTH SYSTEMS SOUTHWEST Reference Figure 16-2 Table 16-I Table 16-J Table 16-U (San Andreas fault) Table 16-5 Table 16-T Table 16-Q Table 16-R March 22, 2006 -16- File No.: 07762-02 06-03-821 The CBC seismic coefficients are based on scientific knowledge, engineering judgment, and compromise. If further information on seismic design is needed, a site-specific probabilistic seismic analysis should be conducted. The intent of the CBC lateral force requirements is to provide a structural design that will resist collapse to provide reasonable life safety from a major earthquake, but may experience some structural and nonstructural damage. A fundamental tenet of seismic design is that inelastic yielding is allowed to adapt to the seismic demand on the structure. In other words, damage is allowed. The CBC lateral force requirements should be considered a minimum design. The owner and the designer should evaluate the level of risk and performance that is acceptable. Performance based criteria could be set in the design. The design engineer should exercise special care so that all components of the design are fully met with attention to providing a continuous load path. An adequate quality assurance and control program is urged during project construction to verify that the design plans and good construction practices are followed. This is especially important for sites lying close to the major seismic sources. 5.9 Pavements Since no traffic loading was provided by the design engineer or owner, we have assumed traffic loading for comparative evaluation. The design engineer or owner should decide the appropriate traffic conditions for the pavements. Maintenance of proper drainage is necessary to prolong the service life of the pavements. Water should not pond on or near paved areas. The following table provides our recommendations for pavement sections. RECOMMENDED PAVEMENTS SECTIONS R -Value Subgrade Soils - 50 (assumed) Design Method — CALTR ANq 1995 1`IVIGJ. 1. Asphaltic concrete should be Caltrans, Type B, 1/2 -in. or 3/4 -in. maximum -medium grading and compacted to a minimum of 95% of the 75 -blow Marshall density (ASTM D l 559) or equivalent. 2. Aggregate base should be Caltrans Class 2 (3/4 in. maximum) and compacted to a minimum of 95% of ASTM D1557 maximum dry density near its optimum moisture. 3. All pavements should be placed on 12 inches of moisture -conditioned subgrade, compacted to a minimum of 90% of ASTM D 1557 maximum dry density near its optimum moisture. 4. Portland cement concrete should have a minimum of 3250 psi compressive strength @ 28 days. 5. Equivalent Standard Specifications for Public Works Construction (Greenbook) may be used instead of Caltrans specifications for asphaltic concrete and aggregate base. EARTH SYSTEMS SOUTHWEST Flexible Pavements Rigid Pavements Asphaltic Concrete Aggregate Base Portland Aggregate Cement Base Traffic Index Pavement Use Thickness Thickness Concrete Thickness Assumed Inches Inches Inches Inches 4.0 Auto Parking Stalls 2.5 4.0 4.0 4.0 5.0 Drive Lanes 3.0 4.0 5.0 4.0 7.0 Semi Truck Drive 4.0 4.5 6.0 6.0 Lanes N/A I Trash Truck Areas N/A N/A 8.0 4.0 1`IVIGJ. 1. Asphaltic concrete should be Caltrans, Type B, 1/2 -in. or 3/4 -in. maximum -medium grading and compacted to a minimum of 95% of the 75 -blow Marshall density (ASTM D l 559) or equivalent. 2. Aggregate base should be Caltrans Class 2 (3/4 in. maximum) and compacted to a minimum of 95% of ASTM D1557 maximum dry density near its optimum moisture. 3. All pavements should be placed on 12 inches of moisture -conditioned subgrade, compacted to a minimum of 90% of ASTM D 1557 maximum dry density near its optimum moisture. 4. Portland cement concrete should have a minimum of 3250 psi compressive strength @ 28 days. 5. Equivalent Standard Specifications for Public Works Construction (Greenbook) may be used instead of Caltrans specifications for asphaltic concrete and aggregate base. EARTH SYSTEMS SOUTHWEST March 22, 2006 - 17 - File No.: 07762-02 06-03-821 Section 6 LIMITATIONS AND ADDITIONAL SERVICES 6.1 Uniformity of Conditions and Limitations Our findings and recommendations in this report are based on selected points of field exploration, laboratory.testing, and our understanding of the proposed project. Furthermore, our findings and recommendations are based. on the assumption that soil conditions do not vary significantly from those found at specific exploratory locations. Variations in soil or groundwater conditions could exist between and beyond the exploration points. The nature and extent of these variations may not become evident until. construction. Variations in soil or groundwater may require additional studies; consultation, and possible revisions to our recommendations. Findings of this report are valid as of the issued date of the report. However, changes in conditions of a property can occur with passage of time whether they are from natural processes or works of man on this or adjoining properties. In addition, changes in applicable standards occur whether they result from legislation or broadening of knowledge. Accordingly, findings of this report may be invalidated wholly or partially by changes outside our control. Therefore, this report is subject to review and should not be relied upon after a period of one year. In the event that any changes in the nature, design, or location of structures are planned, the conclusions and recommendations contained in.this report shall not be considered valid unless the changes are reviewed and conclusions of this report are modified or verified in writing. This report is issued with the understanding that the owner, or the owner's representative, has the responsibility to bring the information and recommendations contained herein to the attention of the architect and engineers for the project so that they are incorporated into the plans and specifications for the project. The owner, or the owner's representative, also has the responsibility to take the necessary steps to see that the general contractor and all subcontractors follow such recommendations. It is further understood that the owner or the owner's representative is responsible for submittal of this report to the appropriate governing agencies. As the Geotechnical Engineer of Record for this project, Earth Systems Southwest (ESSW) has striven to provide our services in accordance with generally accepted geotechnical engineering practices in this locality at this time. No warranty or guarantee is express or implied. This report was prepared for the exclusive use of the Client and the Client's authorized agents. ESSW should be provided the opportunity for a general review of final design and specifications in order that earthwork and foundation - recommendations may be properly interpreted and implemented in the design and specifications. If ESSW is not accorded the privilege of making this recommended review, we can assume no responsibility for misinterpretation of our recommendations. Although available through ESSW, the current scope of our services does not include an environmental assessment, or investigation for the presence or absence of wetlands, hazardous or toxic materials in the soil, surface water, groundwater or air on, below, or adjacent to the subject property. EARTH SYSTEMS SOUTHWEST March 22, 2006 - 18 - File No.: 07762-02 06-03-821 6.2 Additional Services This report is based • on the assumption "that an adequate program of client consultation, construction monitoring, and testing will be performed during the final design and construction phases to' check compliance with these recommendations. Maintaining ESSW as the geotechnical consultant from beginning to end of the project will provide continuity of services. The geotechnical engineering firm providing tests and observations shall assume the responsibility of Geotechnical Engineer of Record. Construction monitoring and testing would be additional services provided by our firm. The costs of these services are not included in our present fee arrangements, but can be obtained from our office: The recommended review, tests, and observations include, but are not necessarily limited to the following: • Consultation during the final design stages of the project • Review of the building and grading plans to observe that recommendations of our report have been properly implemented into the design. • Observation and testing during site preparation, grading and placement of engineered fill as required by UBC Sections 1701- and 3317 or.local grading ordinances. • Consultation as required during construction. •1• Appendices as cited are attached and complete this report. EARTH SYSTEMS SOUTHWEST March 22, 2006 _19- File No.: 07762-02 06-03-821 REFERENCES Abrahamson, N., and Shedlock, K., editors, 1997, Ground motion attenuation relationships: Seismological Research Letters, v. 68, no. 1, January 1997 special issue, 256 p. Blake, B.F., 1998a, FRISKSP v. 3.01b, A Computer Program for the Probabilistic Estimation of Peak Acceleration and Uniform Hazard Spectra Using 3-D Faults as Earthquake Sources, Users Manual, 191 p. Blake, B.F., 1998b, Prelirrunary Fault -Data for EQFAULT and FRISKSP, 71 p. Boore, D.M., Joyner, W.B., and Fumal, T.E., 1993, Estimation of Response Spectra and Peak Accelerations from Western North American Earthquakes: An Interim Report; U.S. Geological,Sur'vey Open -File Report 93-509, 15 p. Boore, D.M., Joyner, W.B., and Fumal, T.E., 1994, Estimation of Response Spectra and Peak Acceleration from Western North American Earthquakes: An Interim Report, Part 2, U.S. Geological Survey Open -File Report 94-127. California Department of Conservation, Division of Mines and Geology: Guidelines for Evaluating and Mitigating Seismic Hazards in California, Special Publication 117, WWW Version. Envicom, Riverside County, 1976, Seismic Safety Element. Ellsworth, W.L., 1990, "Earthquake History, 1769-1989" in: The San Andreas Fault System, California: U.S. Geological Survey Professional Paper 1515, 283 p.. Hart, E.W., 1994 rev., Fault -Rupture Hazard Zones in California: California Division of Mines and Geology Special Publication 42, 34 p. International Conference of Building Officials, 1997, Uniform Building Code,' 1997 Edition. International Conference of Building Officials, 2000, International Building Code, 2000 Edition. Jennings, CW, 1994, Fault Activity Map of California and Adjacent Areas: California Division of Mines and Geology, Geological Data Map No. 6, scale 1:750,000. Joyner, W.B., and Boore, D.M., 1994, Prediction of Ground Motion in North America, in Proceedings of ATC -35 Seminar on New Developments in Earthquake Ground Motion Estimation and Implications for Engineering Design Practice, Applied Technology Council, 1994. Petersen, M.D., Bryant, W.A., Cramer, C.H., Cao, T., Reichle, M.S., Frankel, A.D., Leinkaemper, J.J., McCrory, P.A., and Schwarz, D.P., 1996, Probabilistic Seismic Hazard Assessment for the State of California: California Division of Mines and Geology Open -File Report 96-08, 59 p. Proctor, Richard J. (1968), Geology of the Desert Hot Springs - Upper Coachella Valley Area, California Division of Mines and Geology, DMG Special Report 94. EARTH SYSTEMS SOUTHWEST March 22, 2006 -207 File No.: 07762-02 06-03-821 Riverside County (1984), Seismic Safety Element of the Riverside County General Plan, Amended. Rogers, T.H., 1966, Geologic Map of California - Santa Ana Sheet, California Division of Mines and Geology Regional Map Series, scale 1:250,000. Seed, H.B. and Idriss, I.M., 1982, Ground Motions and Soil Liquefaction During Earthquakes. Sieh, K., ,Stuiver, M., and Brillinger, D., 1989, A More Precise Chronology of Earthquakes Produced by the San Andreas Fault in Southern California: Journal of Geophysical Research, Vol. 94, No. B 1, January 10, 1989, pp. 603-623. Seih, Kerry, 1985, Earthquake Potentials Along -The San Andreas Fault, Minutes of The National Earthquake Prediction Evaluation Council, March 29-30, 1985, USGS Open File Report 85- 507. Structural Engineers Association of California (SEAOC), 1996, Recommended Lateral Force Requirements and Commentary. Tokimatsu, K, and Seed, H.B., 1987, Evaluation of Settlements in Sands Due To Earthquake Shaking, ASCE, Journal of Geotechnical Engineering, Vol. 113, No. 8, August 1987. Van de Kamp, P.C., 1973, Holocene Continental Sedimentation in the Salton Basin, California: A Reconnaissance, Geological Society of America, Vol. 84, March 1973. Working Group on .California Earthquake Probabilities, 1995, Seismic Hazards in Southern California: Probable Earthquakes, 1994-2024: Bulletin of the Seismological Society of America, Vol. 85, No. 2, pp. 379-439. Wallace, R: E., 1990, The San Andreas Fault System, California: U.S. Geological Survey Professional Paper 1515, 283 p. 0 EARTH SYSTEMS SOUTHWEST I APPENDIX A Figure 1 - Vicinity Map Figure 2 - Boring Location Map Table 1 Fault Parameters Logs of Borings 116°16'12"W gR7rinn rA77nn Q - O +itWnt c�kss.. YtP Y _ 1'.W .;v" a- acS...S7�b� ¢ l _ � 5�5f6�� PfiZl&y. �Fi c.ren9P i� � 1� i fkN9�[;� I 1 t.n�8i W��^��w}�•%� f �1 df7X �! d �Py�� +� Yl i�`[ -.f C4,� 'It I� , w,ic, � r' � �� ``L'--. I —=0 „Mi .v ♦ ''. � 11 .., f i p � j �SF •• pO �' t0 �4 , /,r�+ L i :5:. � 3L.; , _ � _ d 'Ctl a ,r �H }` S 1+4>: � .�?L'nf� 1 i •- I ' i ��/' ulo� I 'n�♦ ttk �(t'U S 4^ o �: ` y Y 1!� ,•.tY q } ; L ,� }�iy � l L: �� ,G � i :'S�i � Y i t' +'� td r w',''`ce5*iy.< CM }s . �t1 ' ♦ t� fs1 '*[3"`C1xt �fi� X45 _9P� /0 •A Ir T� } ��J �a 4 � � �i� �91i • C CD" • F.�j.`ac Ok .Fo-f 61 fl (� , �. 3'� j�►� u"---�`.�x�'i�i. a mt _ � �... >. � �� p�1 ��J�� t ,. •9 � B�J� 2 Tf� s � - ��i�r� ny-. ' t ft t 'YY�;•1'�1 LlEtj. o. o .7 P nx•& ,,+q.'P {??yy�y,,� t�i. f%��-'.�/n y.,r.,.1{S.'t��,a2y'?ny � �r.� '��(�9 fdRjiE�' . � �� 1 _¢�.'.� k H,. � . r�.F�,��.��r'�g'�''��, t t '�i:l� �,u ',(tr, i ,A� V r! r'[5'" f PYA A .. ,,f H��' ' g�•q"'tF�ii"> G 4 ��.t.. ' O In N r' . 567300 567400 567500 tQ 567600 567700 116°16 27"W 116'16'12"W 0 55 110 220 330 440 550 Feet Figure 2 LEGEND, I .. r N 'Boring Location Map Existing Boring (ESSW 2006) site Boundary Commercial Development SWC Highway 111 & Jefferson Street Boring Location'. : i , City of Indio La Quints, Riverside County, California ....... City Boundary,City of La Quints f � .40 Earth Systems Southwest 02/25/06 File No.: 07762-02 DESCRIPTIVE SOIL CLASSIFICATION Soil classification is based on ASTM Designations D 2487 and D 2488 (Unified Soil Classification System). Information on each boring log is a compilation of subsurface conditions obtained from the field as well as from laboratory testing of selected samples. The indicated boundaries between strata on the boring logs are approximate only and may be transitional. 12" 3" 3/4" SOIL GRAIN SIZE U.S. STANDARD SIEVE in An 9nn BOULDERS COBBLES GRAVEL SAND SILT CLAY COARSE FINE COARSE MEDIUM FINE 3uD 76.2 19.1 4.16 2.00 U.42 0.074 SOIL GRAIN SIZE IN MILLIMETERS 0.002 RELATIVE DENSITY OF GRANULAR SOILS (GRAVELS, SANDS, AND NON -PLASTIC SILTS) Very Loose *N=0-4 RD=0-30 Easily push a 1/2 -inch reinforcing rod by hand Loose N=5-10 RD=30-50 Push a 1/2 -inch reinforcing rod by hand Medium Dense N=11-30 RD=50-70 Easily drive a 1/2 -inch reinforcing rod with hammer Dense N=31-50 RD=70-90 Drive a 1/2 -inch reinforcing rod 1 foot with difficulty by a hammer Very Dense N>50 RD=90-100 Drive a 1/2 -inch reinforcing rod a few inches with hammer *N=Blows per foot in the Standard Penetration Test at 60% theoretical energy. For the 3 -inch diameter Modified California sampler, 140 -pound weight, multiply the blow count by 0.63 (about 2/3) to estimate N. If automatic hammer is used, multiply a factor of 1.3 to 1.5 to estimate N. RD=Relative Density (%). C=Undrained shear strength (cohesion). CONSISTENCY OF COHESIVE SOILS (CLAY OR CLAYEY SOILS) Very Soft *N=0-1 *C=0-250 psf Squeezes between fingers Soft N=24 C=250-500 psf Easily molded by finger pressure Medium Stiff N=5-8 C=500-1000 psf Molded by strong finger pressure Stiff N=9-15 C=1000-2000 psf Dented by strong finger pressure Very Stiff N=16-30 C=2000-4000 psf Dented slightly by finger pressure Hard N>30 C>4000 Dented slightly by a pencil point or thumbnail MOISTURE DENSITY Moisture Condition: An observational term; dry, damp, moist, wet, saturated. Moisture Content: . The weight of water in a sample divided by the weight of dry soil in the soil sample LOG KEY SYMBOLS expressed as a percentage. PLASTICITY Dry Density: The pounds of dry soil in a cubic foot. DESCRIPTION FIELD TEST ' MOISTURE CONDITION RELATIVE PROPORTIONS Dry .....................Absence of moisture, dusty, dry to the touch Trace ............. minor amount (<5%) Damp................Slight indication of moisture with/some...... significant amount Moist.................Color change with short period of air exposure (granular soil) modifier/and... sufficient amount to Below optimum moisture content (cohesive soil) influence material behavior Wet....................High degree of saturation by visual and touch (granular soil) (Typically >30%) High Above optimum moisture content (cohesive soil) Saturated .......... Free surface water after reaching the plastic limit. LOG KEY SYMBOLS PLASTICITY DESCRIPTION FIELD TEST ' Bulk, Bag or Grab Sample Nonplastic A 1/8 in. (3 -mm) thread cannot be rolled Standard Penetration at any moisture content. Split Spoon Sampler Low The thread can barely be rolled. (2" outside diameter) Medium The thread is easy to roll and not much time is required to reach the plastic limit. ' Modified California Sampler MMoutside High The thread can be rerolled several times diameter) after reaching the plastic limit. No Recovery GROUNDWATER LEVEL • Water Level (measured or after drilling) Terms and Symbols used on Boring L Water Level (during drilling) GRAPHIC LETTER MAJOR DIVISIONS SYMBOL SYMBOL TYPICAL DESCRIPTIONS '•� • Well-graded gravels, gravel-sand CLEAN :'�:':':': GW mixtures, little or no fines GRAVELS is is i(• is r•ii: if• i• ' .•..••.■..■..•r ■•.■• +•. < 5o /° FINES GRAVEL AND +• .•.■• .• ■l.+•.+•..•. r ::•:• r.;:.:•:• GP Poorly-graded gravels, gravel-sand GRAVELLY ■ ■ + ■ ■ .! .• .+ . mixtures. Little or no fines SOILS :�:�:■:' : ;'. GM Silty gravels, gravel-sand-silt COARSE More than 50% of GRAVELS ............ mixtures GRAINED SOILS coarse fraction WITH FINES retained on No. 4 > 12% FINES Clayey gravels, gravel-sand-clay sieve GC mixtures SW Well-graded sands, gravelly sands, SAND ANDCLEAN SAND little or no fines SANDY SOILS (Little or no fines) < 5%SP Poorly-graded sands, gravelly More than 50% of sands, little or no fines material is laroer - -- --- - than No. 200 sieve size SAND WITH FINES :':: '':.:..:::.; . SM Silty sands, sand-silt mixtures More than 50% of (appreciable �• coarse fraction amount) f fines) ones ap ssing No. 4 sieve > 12% SC Clayey sands, sand-clay mixtures Inorganic silts and very fine sands, ML rock flour, silty low clayey fine sands or clayey silts with slight plasticity FINE-GRAINED LIQUID LIMIT Inorganic clays of low to medium LESS THAN 50 CL plasticity, gravelly clays, sandy SOILS clays, silty clays, lean clays OL Organic silts and organic silty clays of low plasticity Y P tY SILTS AND CLAYS Inorganic silty, micaceous, or MH diatomaceous fine sand or silty soils 50% or more of material is smaller LIQUID LIMIT/ Inorganic clays GREATER CH ofhigh plasticity, than No. 200 fat clays sieve size THAN 50 OH Organic clays of medium to high plasticity, organic silts HIGHLY ORGANIC SOILS yy.Yy.Yy.YJ'.Y.YJ'y yyv.YyJ'J'.Yy .ryr�r.rrryryyr PT Peat, humus, swamp soils with yyyyyyyyyyyy high organic contents yyyyyyyyyyyy VARIOUS SOILS AND MAN MADE MATERIALS Fill Materials MAN MADE MATERIALS Asphalt and concrete Soil Classification System Earth Systems '— Southwest Earth Systems Southwest 5 10 15 20 25 30 35 40 45 50 55 79-8116 Country Club Drive, Bermuda Dunes, CA 92201 Pbone (760) 345-1588 FAX (760) 345-7315 Boring No:. B2 SILTY SAND: brown, fine grained, medium dense Drilling Date: May 23, 2000 Project Name: La Quinta Commercial Park 11,7,880.8 Drilling Method: 8" Hollow Stem Auger 0.7 File Number: 07762-01 Drill Type: Mobile 63 Boring Location: Per Plan 101.9 1.4 Logged By: Clifford W. Batten Sample 10,15,20' 86.1 1.0 Type Penetration 15,15,27 �' Description of Units Page 1 of 1 87.3 1.1 nResistance "= o E `n U cz q 8 — •o & Note: The stratification lines shown represent the cr A Y A a o (Blows/6") > A > `g q ❑ U approximate boundary between soil and/or rock types Graphic Trend m v, and the transition may be gradational. Y Sm Blow Count Dry Density 5 10 15 20 25 30 35 40 45 50 55 0 SM SILTY SAND: brown, fine grained, medium dense 11,7,880.8 0.7 to dense, dry 7,10,10 101.9 1.4 10,15,20' 86.1 1.0 15,15,27 87.3 1.1 10,15,15 86.7 2.0 14,20,40 13,15,20 ffl ML SILT: light brown, medium dense, dry 17,20,30 ' SM SILTY SAND: brown, fine grained, medium dense to dense, dry 10,13,20 ML SILT: light brown, medium dense, dry 10,t8,2o SM SILTY SAND: brown, fine to medium grained, dense, dry 15,26,30 TOTAL DEPTH: 51.5' No Bedrock or Groundwater Encountered 0 Earth Systems Southwest 79-811 B Country Club Drive, Bermuda Dunes, CA 92201 5 10 15 20 25 30 35 40 45 50 55 Ynone (/GU) 345-15tSi5 I'AX (/6U) 345-/315 Boring No: B3 SILTY SAND: brown, fine grained, medium dense Drilling Date: May 23, 2000 Project Name: La Quinta Commercial Park Drilling Method: 8" Hollow Stem Auger File Number: 07762-01 72.6 1.2 Drill Type: Mobile 63 Boring Location: Per Plan Logged By: Clifford W. Batten 19,21,30 Sample Type Penetration _ 1.2 °:' Description of Units Pa e l of 1 g aType,,, � Resistance � U � °' A g B Y •o Y Note: The stratification lines shown represent the P d Y pA o (Blows/6") SILTY SAND: brown, fine to medium grained, medium dense to dense, dry c U approximate boundary between soil and/or rock types Graphic Trend 14,16,18 w rn � 101.6 0.9 12 and the transition may be gradational. Y 8m Blow Count Dry Density 5 10 15 20 25 30 35 40 45 50 55 SM SILTY SAND: brown, fine grained, medium dense 14,14,14 72.6 1.2 to dense, dry 19,21,30 ML 86.8 1.2 SILT: brown, medium dense, dry 22,25,31 SM 90.7 0.9 SILTY SAND: brown, fine to medium grained, medium dense to dense, dry 14,16,18 101.6 0.9 .. t 21,29,26 82.7 1.7 9,11,21 18,17,15 ML SILT: light brown, medium dense, dry a T. SM SILTY SAND: brown, fine to medium grained, S, t 9,21 dense, dry 19,16,15 ML SILT: light brown, medium dense, dry 16,18 20 ' SM SILTY SAND: brown, fine to medium grained, dense, dry 14,18,21 TOTAL DEPTH: 51.5' No Bedrock or Groundwater Encountered Earth Systems - Southwest 79-8I 1B Country Club Drive, Bermuda Dunes, CA 92201 Phone (760) 345-1588 FAX (760) 345-7315 BorinNo: B5 Drilling Date: May 23, 2000 Project ame: La Quinta Commercial Park Drilling Method: 8" Hollow Stem Auger File Number: 07762-01 Drill Type: Mobile 63 Boring Location: Per Plan Logged By: Clifford W. Batten 5 10 15 20 25 30 35 40 45 50 55 Sample Type m0 Penetration S1v1 Description of Units Page I of 1 aResistance 6 DO U r, A 3 . - Note: The stratification lines shown represent the A g 1 A o a o (Blows/6") >, A � c approximate boundary between soil and/or rock types Graphic Trend 14,16,20 92.0 A U and the transition may be gradational. Y Sr Blow Count Dry Density 5 10 15 20 25 30 35 40 45 50 55 S1v1 SILTY SAND: brown, fine to medium grained 20,21,25 102.0 o.s medium dense to dense, dry 14,16,20 92.0 1.7 19,18,19 90.2 3.0 15,20,21 96.5 0.8 12,18,19 98.9 0.9 16,18,19 18,20,27 TOTAL DEPTH: 31.5' No Bedrock or Groundwater Encountered JOA Earth Systems Southwest 79-811B Country Club Drive, Bermuda Dunes, CA 92201 - 5- -10 - 15 - 20 - 25 - 30 - 35 -40 - 45 - 50 55 rnoue (+ou) 345-ussss YAX (Y(JV) 345-7315 BorinNO: B6 Erne: SILTY SAND: brown, fine to medium grained, Drilling Date: May 23, 2000 ProjecLa Quinta Commercial Park Drilling Method: 8" Hollow Stem Auger File Number: 07762-01 104.3 0.7 Drill Type: Mobile 63 Boring Location: Per Plan Logged By: Clifford W. Batten 8,10,16 Sample Type Penetration 84.3 1.0 , , ... Description of Units Pae 1 of 1 g U Resistance 13,16,20 A 2 a°i Note: The stratification lines shown represent the q a y o (Blows/6") ML Q C j approximate boundary between soil and/or rock types Graphic Trend cq damp and the transition may be Sradational. Blow Count Dry Density - 5- -10 - 15 - 20 - 25 - 30 - 35 -40 - 45 - 50 55 SM SILTY SAND: brown, fine to medium grained, 20,20,19 104.3 0.7 medium dense to dense, dry 8,10,16 84.3 1.0 13,16,20 89.5 1.9 ML SILT: brown, laminated, medium dense, dry to damp 17,20,40 75.6 4.3 , 22,30,34 91.2 3.1 19,20,22 SM SILTY SAND: brown, fine to medium grained, medium dense to dense, dry 15,25,32 TOTAL DEPTH: 31.5' No Bedrock or Groundwater Encountered I Aft Earth Systems W Southwest 5 10 15 20 25 30 t 35 - 40 45 50 55 79-811B Country Club Drive, Bermuda Dunes, CA 92201 Pbone (760) 345-1588 FAX (760)345-7315 SM Boring No: B8 SILTY SAND: brown, fine to mediumgrained Drilling Date: May 23, 2000 Project Name: La Quinta Commercial Park 50 for 5" Drilling Method: 8" Hollow Stem Auger 1.0 File Number: 07762-01 Drill Type: Mobile 63 50 for 5" Boring Location: Per Plan 107.5 1.4 Logged By: Clifford W. Batten Sample Type Penetration— o 10,15,22 E! of Units Page 1 of 1 5.8 CL c" Resistance E C q •F, ,cam Note: The stratification lines shown represent the a) A Y o a a o (Blows/6") > ] ` `' o approximate boundary between soil and/or rock types Graphic Trend to rn � SM A V and the transition may be gradational. Blow Count Dry Density 5 10 15 20 25 30 t 35 - 40 45 50 55 ' SM SILTY SAND: brown, fine to mediumgrained 50 for 5" 100.8 1.0 medium dense to dense, dry 50 for 5" T. 107.5 1.4 10,15,22 ML 91.0 5.8 SILT: brown, laminated, medium dense, damp 10,14,21 85.1 5.7 SM SILTY SAND: brown, fine to medium grained, 18,21,25 93.5 3.4 medium dense to dense, dry TOTAL DEPTH: 21.5' No Bedrock or Groundwater Encountered !§ Earth Systems Southwest 79-811B Country Club Drive, Bermuda Dunes, CA 92201 Phone (760) 345-1588 FAX (760) 345-7315 Boring No: B9 Drilling Date: May 23, 2000 Project Name: La Quinta Commercial Park SILTY SAND: brown, fine to medium grained Drilling Method: 8" Hollow Stem Auger File Number: 07762-01 i Drill Type: Mobile 63 Boring Location: Per Plan 91.9 1.0 Logged By: Clifford W. Batten Sample Type Penetration 16,17,19 °:' Description of Units Page 1 of 1 o 1.5 Resistance U Note: The stratification lines shown represent the P a> C) >eo 5 aa. o (Blows/6") >, 3.8 A c U approximate boundary between soil and/or rock types Graphic Trend C1 W 18,19,21 and the transition may be gradational. y Blow Count Dry Density 5 10 15 20 25 30 35 40 45 50 55 SM SILTY SAND: brown, fine to medium grained 20,31,50 91.9 1.0 medium dense to dense, dry 16,17,19 100.6 1.5 11,14,18 92.5 3.8 18,19,21 - 11,14,18 86.1 1.0 TOTAL DEPTH: 21.5 No Bedrock or Groundwater Encountered Earth Systems Southwest IIW 79-811B Country Club Drive, Bermuda Dunes, CA 92201 Phone (760) 345-1588 FAX (760) 345-7315 Boring No: B11 SANDY SILT: brown, laminated, medium dense, dry Drilling Date: May 23, 2000 Project Name: La Quinta Commercial Park TOTAL DEPTH: 16.5' Drilling Method: 8" Hollow Stem Auger File Number: 07762-01 Drill Type: Mobile 63 No Bedrock or Groundwater Encountered Boring Location: Per Plan Logged By: Clifford W. Batten Sample Typew Penetration a '� 2' Description Of Units Page 1 of 1 y a A Resistance 6 U.W rn A a c Y Note: The stratification lines shown represent the p ar A D 5 oo,, o (Blows/6") > � > `' A o o approximate boundary between soil and/or rock types Graphic Trend ao v� U and the transition may be gradational. Y Blow Count Dry Density 5 10 15 20 25 30 35 40 45 50 55 s 8,13,15 9,11,14 8,16,13 10,12,15 ML SANDY SILT: brown, laminated, medium dense, dry TOTAL DEPTH: 16.5' No Bedrock or Groundwater Encountered a tEarth Systems Southwest 79-811B Country Club Drive, Bermuda Dunes, CA 92201 5 10 15 20 25 30 35 40 45 50 55 8,11,14 5,14,15 rnOne(/0U)343-135b I-AA(/OU)34:1-/31� Boring No: B12 SILTY SAND: brown, very fine to fine grained medium dense, dry Drilling Date: May 23, 2000 Project Name: La Quinta Commercial Park SANDY SILT: brown, laminated, medium dense, Drilling Method: 8" Hollow Stem Auger File Number: 07762-01 Drill Type: Mobile 63 Boring Location: Per Plan Logged By: Clifford W. Batten Sample Type Penetration _ „ o . ... Description of Units Page 1 of 1 A _ Resistance 6 � A g 8 r. .� o 's! Note: The stratification lines shown re resent the P A Y q (Blows/6") > AU a j approximate boundary between soil and/or rock types Graphic Trend . and the transition may be gradational. Blow Count Dry Density 5 10 15 20 25 30 35 40 45 50 55 8,11,14 5,14,15 SM ML SILTY SAND: brown, very fine to fine grained medium dense, dry SANDY SILT: brown, laminated, medium dense, dry 17,26 29 12,14,14 TOTAL DEPTH: 16.5' No Bedrock or Groundwater Encountered •JOA Earth Systems .Southwest. 79-81113 Country Club Drive, Bermuda Dunes, CA 92201 Phone (760) 345-1588 FAX (760) 345-7315 Boring No: B13 97.8 • 0.5 SILTY SAND: brown, very fine to fine grained, medium dense, dry Drilling Date: May 23, 2000 Project Name: La Quinta Commercial Park TOTAL DEPTH: 6.5' Drilling Method: 8" Hollow Stem Auger File Number: 07762-01 Drill Type: Mobile 63 No Bedrock or Groundwater Encountered Boring Location: Per Plan Logged By: Clifford W. Batten v Sample Type,,, Penetration:?' Penetration- Description of Units Page 1 of 1 oResistance n q g i; Y •o Y Note: The stratification lines shown represent the q (Blows/6") q A 2 o approximate boundary between soil and/or rock types Graphic Trend U and the transition may be gradational. Blow Count Dry Density -5 - 10 - 15 - 20 - 25 - 30 - 35 -40 - 45 50 55 18,19,21 23,31,40 SM 97.8 • 0.5 SILTY SAND: brown, very fine to fine grained, medium dense, dry TOTAL DEPTH: 6.5' No Bedrock or Groundwater Encountered Earth Systems Southwest 79-811B Country Club Drive, Bermuda Dunes, CA 92201 5 10 15 20 25 30 35 x 40 45 50 55 18,28,31 19,21,33 rllunckfoV)J43-1J86 rN.c t/OV)091-/Sly BorinNO: B14 98.8 96.5 0.7 0.7 SILTY SAND: brown, fine grained, medium dense, dry Drilling Date: May 23, 2000 Project ame: La Quinta Commercial Park TOTAL DEPTH: 6.5' Drilling Method: 8" Hollow Stem Auger File Number: 07762-01 Drill Type: Mobile 63 Boring Location: Per Plan No Bedrock or Groundwater Encountered Logged By: Clifford W. Batten Sample Type Penetration o °? Description of Units IPage 1 of 1 aResistance 4 oaCi E U q g a . •o & Note: The stratification lines shown represent the ar C1 -,.eq a o (Blows/6") >, N q A c approximate boundary between soil and/or rock types Graphic Trend U and the transition may be gradational. Y gr Blow Count Dry Density 5 10 15 20 25 30 35 x 40 45 50 55 18,28,31 19,21,33 SM 98.8 96.5 0.7 0.7 SILTY SAND: brown, fine grained, medium dense, dry TOTAL DEPTH: 6.5' No Bedrock or Groundwater Encountered 4 A Earth Systems WWI- SOYthweSt 79-81 IB Country Club Drive, Bermuda Dunes, CA 92203 5 10 15 20' 25 30 35 40 ruone thou) i43-I:,in6, rax (fou) s43 -/S1 :) Boring No: B-1 SAND WITH SILT: pale yellowish brown, medium Drilling Date: February 27, 2006 Project Name: SWC Highway 111 & Jefferson Street, La Quinta, CA Drilling Method: 8" Hollow Stem Auger File Number: 07762-02 Drill Type: CME 75 W/Auto Hammer Boring Location: See Figure 2 dense, dry, fine to medium grained Logged By: Dirk Wiggins 1 Sample Type Penetration _ y o : '.�� g Description of Units Pae 1 of 1 a w U Resistance O E to � °' A a 2 ar. r o Note: The stratification lines shown represent the A Y q (Blows/6") A > c approximate boundary between soil and/or rock types Graphic Trend 10,12,16 Cl U and the transition may be gradational. Y B� Blow Count Dry Density 5 10 15 20' 25 30 35 40 SP -SM SAND WITH SILT: pale yellowish brown, medium dense, dry, fine to medium grained 6,7,9 2,4,7 10,12,16 6,11,14 Total Depth 16.5 feet No Groundwater Encountered tEarth Systems Southwest 79-811 B Country Club Drive, Bermuda Dunes, CA 92203 5 10 15 20 25 30 35 40 rnone t/ov) 34o -I Jbb, rax t/ouf s4:)-/313 Boring No: B-2 SAND WITH SILT: pale yellowish brown, dry, Drilling Date: March 1, 2006 Project Name: SWC Highway 111 & Jefferson Street, La Quinta, CA Drilling Method: 8" Hollow Stem Auger File Number: 07762-02 fine to coarse grained Drill Type: CME 75 W/Auto Hammer Boring Location: See Figure 2 3,6,9 Logged By: Dirk Wiggins u., ...J Sample Type Penetration W o � � °' � ...• � " Description Page 1 of 1 p tion of Units aResistance SILTY SAND: pale yellowish brown, medium U t[i � q •o y Note: The stratification lines shown represent the q Y p (Blows/6") dense, damp, very fine to fine grained q Tg Ca c approximate boundary between soil and/or rock types Graphic Trend 5,10,13 co � ML 91 3 V and the transition may be gradational. Blow Count Dry Density 5 10 15 20 25 30 35 40 SP -SM SAND WITH SILT: pale yellowish brown, dry, fine to coarse grained 3,6,9 92 3 SM SILTY SAND: pale yellowish brown, medium dense, damp, very fine to fine grained 5,10,13 ML 91 3 SILT: pale yellowish brown, medium dense, dry, very fine to fine grained, CL lenses, SM Lenses 4,12,16 SP -SM SAND WITH SILT: pale yellowish brown, medium dense, dru, very fine to medium grained 5,11,15 fine to medium grained, micaceous Total Depth 21.5 feet No Groundwater Encountered • Earth Systems ' ^� Southwest 79-81113 Country Club Drive, Bermuda Dunes, CA 92203 5 10 15 20 25 30 35 40 rnune (/ov) �4�-1 �btS, rax (/DU) S43- /31 Boring N0: B-3 SAND WITH SILT: pale yellowish brown, medium Drilling Date: March 1, 2006 ProjectName: SWC Highway 111 & Jefferson Street; La Quinta, CA Drilling Method: 8" Hollow Stem Auger File Number: 07762-02 Drill Type: CME 75 W/Auto Hammer Boring Location: See Figure 2 dense, dry, fine to medium grained, organic matter Logged By: Dirk Wiggins ,..� Sample Type Penetration � .. , g Description of Units Pae 1 of 1 av Resistance o �� A 3 DY •o Y Note: The stratification lines shown represent the A Y p 0. (Blows/6") �, to A p e approximate boundary between soil and/or rock types Graphic Trend 0 � j and the transition may be gradational. Blow Count Dry Density 5 10 15 20 25 30 35 40 SP -SM SAND WITH SILT: pale yellowish brown, medium dense, dry, fine to medium grained, organic matter 3,7,10 1 4,8,12 89 1 ML SILT: pale yellowish brown, medium dense, dry, very fine to fine grianed, CL lenses 7,16,17 SM SILTY SAND: pale yellowish brown, dense, dry, fine to coarse grained 3,7,6 SP -SM SAND WITH SILT: pale yellowish brown, medium dense, dry, fine to medium grained 4,6,7 Total Depth 21.5 feet No Groundwater Encountered Earth Systems Southwest 79-81113 Country Club Drive, Bermuda Dunes, CA 92203 5 10 15 20 25 30 35 40 rnone (rou) 34�-ll60, rax (/bu) 34:)-Y31� Boring No: B-4 SAND WITH SILT: pale yellowish brown, medium Drilling Date: March 1; 2006 Project Name: SWC Highway 111 & Jefferson Street, La Quinta, CA Drilling Method: 8" Hollow Stem Auger File Number: 07762-02 Drill Type: CME 75 W/Auto Hammer Boring Location: See Figure 2 dense, dry, very fine to medium grained, ML ) Logged By: Dirk Wiggins' Sample Type penetration _ :; Description Of Units Page 1 of 1 a U' Resistance U Cn °' Cq s e . o Note: The stratification lines shown represent the p Q p o a o (Blows/6") E, v1 > c approximate boundary between soil and/or rock types Graphic Trend 9,15,14 to cn � 104 1 Ga U and the transition may be gradational. y � Blow -Count Dry Density 5 10 15 20 25 30 35 40 SP -SM SAND WITH SILT: pale yellowish brown, medium dense, dry, very fine to medium grained, ML lenses, CL lenses 7,11,16 84 2 9,15,14 104 1 fine to medium grained 3,6,6 SM SELTY SAND: pale yellowish brown, medium ' dense, dry, fine to medium grained 6,9,10 very fine to medium grained 5,7,6 3,6,7 ML SILT: moderate yellowish brown, medium dense, dry, very fine to fine grained, CL lenses Total Depth 31.5 feet No Groundwater Encountered Earth Systems '�� Southwest 5 10 15 20 25 30 35 40 79-811B Country Club Drive, Bermuda Dunes, CA 92203 Phone (760) 345-1598, Fax (760) 345-7315 Boring No: B-5 SAND WITH SILT: pale yellowish brown, loose, Drilling Date: March 1, 2006 Project Name: SWC Highway 11 I & Jefferson Street, La Quinta, CA Drilling Method: 8" Hollow Stem Auger File Number: 07762-02 Drill Type: CME 75 W/Auto Hammer Boring Location: See Figure 2 Logged By: Dirk Wiggins v Sample Type penetration '� 2 r -- Description of Units (Page 1 off l w U' Resistance 0 E to q n. — 2— •o 2 Note: The stratification lines shown represent the N q Y - ❑ a 0 (Blows/6") �, „'7 L,— q 'g o approximate boundary between soil and/or rock types Graphic Trend co cn � U and the transition may be gradational. y � ' ' Blow Count Dry Density 5 10 15 20 25 30 35 40 SP -SM SAND WITH SILT: pale yellowish brown, loose, dry, fine to medium grained 3,4,5 SM - SILTY SAND: moderate yellowish brown, medium dense, dry, fine to medium grained No Recovery 3,5,7 3,5,7 4,11,16 SP -slut SAND WITH SILT: pale yellowish, medium dense, dry, fine to medium grained 5,9,10 5,5,6 sM SILTY SAND: pale yellowish brown, medium dense, dry, fine to medium grained Total Depth 29 feet No Groundwater Encountered APPENDIX B Laboratory Test Results a UNIT DENSITIES AND MOISTURE CONTENT Job Name: La Quinta Commercial Park File Number: File No.: 07762-01 Date: 07/27/00 . Unit Moisture USCS # Sample Depth Dry Content Group Location (feet) Density (pcf). (%) Symbol Bl 2 99.3 0.6 SM B1 5 78.2 5.2 ML BI 10 -86.6 2.5 SM/ML BI 15 94.0 0.8 SM/ML BI 20 93.0 1.2 SM/ML B2 2 80.8 0.7 SM B2 5 101.9 1.4 SM B2 10 86:1 1.0 SM B2 15 87.3 1.1 SM B2 20 86.7 2.0 SM • B3 2 72.6 1.2 SM B3 5 86.8 1.7 ML B3 10 90.7 0.9 SM B3 15 101.6 0.9 SM B3 20 82.7 1.7 SM B4 2 104.4 0.9 SM B4 5 92.0 1.9 SM B4 10 80.6 2.7 SM B4 .15 98.3 0.7 SM B4 20 83.9 1.8 SM/ML B5 2 102.0 0.8 SM B5 5 92.0 1.7 SM B5 10 90.2 3.0 SM B5 15 96.5 0.8 SM B5 20 98.9 0.9 SM 11 UNIT DENSITIES AND MOISTURE CONTENT Job Name: La Quinta Commercial Park File Number: File No.: 07762-01 Date: 07/27/00 Unit Moisture USCS Sample Depth Dry Content Group Location (feet) Density (pcf) N Symbol B6 2 104.3 0.7 SM B6 5 84.3 1.0 SM B6 10 89.5 1.9 ML B6 15 75.6 4.3 ML B6 20 91.2 3.1 ML B7 2 97.6 3.5 SM B7 5 91.3 4.6 SM B7 10 79.3 8.2 ML B7 15 85.4 5.7 ML B7 20 93.2 1.8 ML B8 2 100.8 1.0 SM B8 5 107.5 1.4 SM B8 10 91.0 5.8 ML B8 15 85.1 5.7 ML B8 20 93.5 3.4 SM B9 2 91.9 T.0 SM B9 5 100.6 1.5 SM B9 10 92.5 3.3 ML B9 20 86.1 1.0 SM B10 2 100.2 1.2 SM BIO 5 94.0 1.6 SM B 13 2 97.8 0.5 SM B14 2 98.8 0.7 SM B14 5 96.5 0.7 SM 100 90 80 en 70 c 60 50 c 40 a� a. 30 20 10 0 100 10 1 0.1 0.01 0.001 Particle Size ( mm) EARTH SYSTEMS CONSULTANTS SOUTHWEST File No.: 07762-01 July 27, 2000 PARTICLE SIZE ANALYSIS ASTM D-422 Job Name: La Quinta Commercial Park Sample ID: B1 @ 0-5' Feet Description: Silty Sand, fine grained with silt lenses (SM) Sieve Percent Size Passing 1-1/2" 100 1" 100 . 3/4" 100 1/2" 100 3/8" 100 #4 100 #8 100 #16 100 % Gravel: 0 #30 99 % Sand: 59 #50 91 % Silt: 30 #100 66 % Clay (3 micron): 11 #200 41 (Clay content by short hydrometer method) 100 90 80 en 70 c 60 50 c 40 a� a. 30 20 10 0 100 10 1 0.1 0.01 0.001 Particle Size ( mm) EARTH SYSTEMS CONSULTANTS SOUTHWEST File No.: 07762-01 July 27, 2000 CONSOLIDATION TEST ASTM D 2435-90 & D5333 La Quinta Commercial Park Initial Dry Density: 84.6 pcf B2 @ 5' Feet Initial Moisture, %: 1.4% Silty Sand, fine grained (SM) Specific Gravity (assumed): 2.67 Ring Sample Initial Void Ratio: 0.970 Hydrocollapse: 1.6% @ 2.0 ksf % Change in Height vs Normal Presssure Diagram O Before Saturation --Hydrocollapse ® After Saturation �1 Rebound Trend 2 1 0 .r on -2 x -3 e -4 au �a -5 U -6 w u -7 L d -8 a -9 -10 -11 -12 0.1 . 1.0 Vertical Effective Stress, ksf EARTH SYSTEMS CONSULTANTS SOUTHWEST 10.0 File No.: 07762-01 July 27, 2000 CONSOLIDATION TEST - ASTM D 2435-90 & D5333 La Quinta Commercial Park Initial Dry Density: 82.3 pcf 136 @ 10' Feet Initial Moisture, %: 1.9% Silty (ML) Specific Gravity (assumed): 2.67 Ring Sample Initial Void Ratio: 1.025 �a A,A, on -2 Z x -3 e -4 en ea -5 s U -6 y v -7 V L -8 a Hydrocollapse: 2.5% @ 2.0 ksf % Change in Height vs Normal Presssure Diagram O Before Saturation —Hydrocollapse ® After Saturation —0—Rebound Trend 1.0 Vertical Effective Stress, ksf EARTH SYSTEMS CONSULTANTS SOUTHWEST 10.0 File No.: 07762-01 July 27, 2000 CONSOLIDATION TEST ASTM D 2435-90 & D5333 La Quinta Commercial Park B7 @ 10' Feet Silt (ML) Ring Sample X, Initial Dry Density: 73.1 pcf Initial Moisture, %: 8.2% Specific Gravity (assumed): 2.67 Initial Void Ratio: 1.280 Hydrocollapse: 2.4% @ 2.0 ksf % Change in Height vs Normal Presssure Diagram O Before Saturation ------- Hydrocollapse ® After Saturation Rebound Trend 1.0 Vertical Effective Stress, ksf EARTH SYSTEMS CONSULTANTS SOUTHWEST 10.0 y File No.: 07762-02 March 22, 2006 UNIT DENSITIES AND MOISTURE CONTENT ASTM D2937 & D2216 Job Name: SWC Jefferson & Hwy 111 B2 5 92 Unit Moisture USCS Sample Depth Dry Content I Group Location (feet) Density (pcf) (%) Symbol B2 5 92 3 SM B2 10 91 3 ML/CL B3 2.5 --- 1 SM B3 5 89 1 ML B4 5 84 2 SM/ML B4 10 104 1 SM } EARTH SYSTEMS SOUTHWEST