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06-3327 (SFD) Geotechnical ReportGEOTECHNICAL INVESTIGATION PROPOSED GRIFFIN RANCH RESIDENTIAL DEVELOPMENT SEC AVENUE 54 AND MADISON STREET LA QUINTA, CALIFORNIA -Prepared By- Sladden Engineering 39-725 Garand Lane, Suite G Palm Desert, California 92211 (760) 772-3893 Sladden Engineering 6782 Stanton Ave., Suite A, Buena Park, CA 90621 (714) 523-0952 Fax (714) 523-1369 39-726 Garand Ln., Suite G, Palm Oesert, CA 92211 (760) 772-3893 Fax (760) 772-3895 August 17, 2004 Transwest Housing, Inc. 47-120 Dune Palms Road, Suite C La Quinta, California 92253 Attention: Mr. Rod Grinberg Project: Proposed Griffin Ranch Residential Development SEC Avenue 54 and Madison Street La Quinta, California Subject: Geotechnical Investigation Project No. 544-4402 04-08-571 Presented herewith is the report of our Geotechnical Investigation conducted for the construction of the proposed approximately 195-acre residential development to be located on the southeast corner of Avenue 54 and Madison Street in the City of La Quinta, California. The investigation was performed in order to provide recommendations for site preparation and to assist in foundation design for the proposed residential structures and the related site improvements. This report presents the results of our field investigation and laboratory testing along with conclusions and recommendations for foundation design and site preparation. This report completes our original scope of services as outlined within our proposal dated July 8, 2004. We appreciate the opportunity to provide service to you on this project. If you have any questions regarding this report, please contact the undersigned Respectfully submitted, SLADDEN ENGINEERING AAIpER�ON1 Brett L. A3]dCl'SO • �� Gd53{ig Principal Engineer ((,� En,rxc� �b SER/pc Copies: 6/Transwest Housing August 17, 2004 4- Project No. 544-4402 04-08-571 Based upon the depth to groundwater and the generally firm condition of the deeper sand layers, it is our opinion that the potential for liquefaction affecting the site is minimal. The remedial grading recommended for building areas will result in the construction of a uniform compacted soil mat beneath all footings. In our opinion, liquefaction related mitigation measures in addition to the site grading and foundation design recommendations included in this report should not be necessary. The site is located in one of the more seismically active areas in California. Design professionals should be aware of the site setting and the potential for earthquake activity during the anticipated life of the structure should be acknowledged. Tile accelerations that may be experienced on the site (as previously discussed) should be considered in design. The seismic provisions included in the Uniform Building Code for Seismic Zone 4 should be considered the minimum design criteria. Pertinent 1997 UBC Seismic Design Criteria is summarized in Appendix C. Caving did occur within our borings and the potential for caving should be expected within deeper excavations. All excavations should be constructed in accordance with the normal CalOSHA excavation criteria. On the basis of our observations of the materials encountered, we anticipate that the near surface silty sands will be classified by CalOSHA as Type C. Soil conditions should be verified in the field by a "Competent person" employed by the Contractor. The near surface soils encountered during our investigation were found to be non -expansive. Laboratory testing indicated an Expansion Index of 0 for the surface silty sands and sandy silts that corresponds with the "very low" expansion category in accordance with UBC Table 18-I-B. The following recommendations present more detailed design criteria which have been developed on the basis of our field and laboratory investigation. The recommendations are based upon non -expansive soils criteria. Foundation Design: The results of our investigation indicate that either conventional shallow continuous footings or isolated pad footings that are supported upon properly compacted soils, may be expected to provide adequate support for the proposed structure foundations. Building pad grading should be performed as described in the Site Grading Section of this report to provide for uniform and firm bearing conditions for the structure foundations. Footings should extend at least 12 inches beneath lowest adjacent grade. Isolated square or rectangular footings should be at least two feet square and continuous footings should be at least 12 inches wide. Continuous footings may be designed using an allowable bearing value of 1500 pounds per square foot (psf) and isolated pad footings may be designed using an allowable bearing pressure of 1800 psf. The allowable bearing pressures are applicable to dead and frequently applied live loads. The allowable bearing pressures may be increased by 1/3 to resist wind and seismic loading. Care should be taken to see that bearing or subgrade soils are not allowed to become saturated from the ponding of rainwater or irrigation. Drainage from the building area should be rapid and complete. Sladden Engineering August 17, 2004 -5- Project No. 544-4402 04-08-571 The recommendations provided in the preceding paragraph are based on the assumption that all footings will be supported upon properly compacted engineered fill soils. All grading should be performed under the testing and inspection of the Soils Engineer or his representative. Prior to the placement of concrete, we recommend that the footing excavations be inspected in order to verify that they extend into compacted soil and are free of loose and disturbed materials. Settlements: Settlements resulting from the anticipated foundation loads should be minimal provided that the recommendations included in this report are considered in foundation design and construction. The estimated ultimate settlements are calculated to be approximately one inch when using the recommended bearing values. As a practical matter, differential settlements between footings can be assumed as one-half of the total settlement. Lateral Design: Resistance to lateral loads can be provided by a combination of friction acting at the base of the slabs or foundations and passive earth pressure along the sides of the foundations. A coefficient of friction of 0.40 between soil and concrete may be used with consideration to dead load forces only. A passive earth pressure of 250 pounds per square foot, per foot of depth, may be used for the sides of footings that are poured against properly compacted native or approved non -expansive import soils. Passive earth pressure should be ignored within the upper 1 foot except where confined (such as beneath a floor slab). Retaining Walls: Retaining walls may be necessary to accomplish the proposed construction. Lateral pressures for use in retaining wall design can be estimated using an equivalent fluid weight of 35 pcf for level free -draining native backfill conditions. For walls that are to be restrained at the top, the equivalent fluid weight should be increased to 55 pcf for level free - draining native backfill conditions. Backdrains should be provided for the full height of the walls. Expansive Soils: Due to the prominence of "very low" expansion categoiy soils near the surface, the expansion potential of the foundation bearing soils should not be a controlling factor in foundation or floor slab design. Expansion potential should be reevaluated subsequent to grading. Concrete Slabs -on -Grade: All surfaces to receive concrete slabs -on -grade should be underlain by a minimum compacted non -expansive fill thickness of 24 inches, placed as described in the Site Grading Section of this report. Where slabs are to receive moisture sensitive floor coverings or where dampness of the floor slab is not desired, we recommend the use of an appropriate vapor barrier or an adequate capillary break. Vapor barriers should be protected by sand in order to .reduce the possibility of puncture and to aid in obtaining uniform concrete curing. Reinforcement of slabs -on -grade in order to resist expansive soil pressures should not be necessary. However, reinforcement will have a beneficial effect in containing cracking due to concrete shrinkage. Temperature and shrinkage related cracking should be anticipated in all concrete slabs -on -grade. Slab reinforcement and the spacing of control jousts should be determined by the Structural Engineer. Sladden Engineering GEOTECHNICAL INVESTIGATION PROPOSED GRIFFIN RANCH DEVELOPMENT SEC AVENUE 54 & MADISON STREET LA QUINTA, CALIFORNIA August 17, 2004 TABLE OF CONTENTS INTRODucTTON ........................... SCOPE OF ........................................ WORK.................................................. ........................................................,........ PROJECT DFSCRIPTION,...�.. ,... ...................................................... GEOLOGY ........................................... AND SEISMICITY ................................ ......................................... SUBSURFACE CONDITIONS........ ................................................... .......................... LI UEFA ............................... Q Cl'ION........,....... ....................................................................... CONCLUSIONS AND RE COI'AMENDATIONS.. .. ..... . Foundation Design ..... •.......... ............ Settlements ........................................................................................................................... ................................................................................................. . Lateral Design ............................................. Retaining Walls........... ............�..............................,..................................................... Expansive Soils ....................................................................................................................... Concrete Slabs-on-Grade .g ..........................................................................,...................................... Soluble Sulfates....................................................................................................................... Tentative Pa Pavement Design ............................................ ........ ................ Shrinkage and Subsidence.............................................................................................................. 6 General Site Grading.............................................................................................................................................. 6 LSite Clearing................................................................................................... 6 .............................................................................................. 6 2. Preparation of Building and Foundation Areas 3. Placement of Compacted Fill.. .................................... ....."................ ..�. 7 4. Preparation of Slab and Pavement Areas 7 ...................................................,.........�... 5. Testing g and Inspection ................................................................... ...... 7 ......................... GENERAL............................................................... REFERENCES........................................................................................................................................ 8 APPENDIX A - Site Plan and Boring Logs Field Exploration APPENDIX B - Laboratory Testing Laboratory Test Results APPENDIX C - 1997 UBC Seismic Design Criteria August 17, 2004 4- Project No. 544-4402 04-08-571 INTRODUCTION This report presents the results of our Geotechnical Investigation performed in order to provide recommendations for site preparation and to assist in the design and construction of the foundations for the single-family residences proposed for the Griffin, Ranch development. The project site is located on the southeast corner of Avenue 54 and Madison Street in the City of La Quinta, California. The preliminary plans indicate that the proposed project will include single-family residences along with various associated site improvements. The associated site improvements are expected to include paved roadways, concrete driveways and patios, underground utilities, and landscape areas. SCOPE OF WORK The purpose of our investigation was to determine certain engineering characteristics of the near surface soils on the site in order to develop recommendations for foundation design and site preparation. Our investigation included field exploration, laboratory testing, literature review, engineering analysis and the preparation of this report. Evaluation of hazardous materials or other environmental concerns was not within the scope of services provided. Our investigation was performed in accordance with contemporary geotechnical engineering principles and practice. We make no other warranty, either express or implied. PROJECT DESCRIPTION Tl1e approximately 195-acre project site is located on the southeast comer of Avenue 54 and Madison Street in the City of La Quinta, California. It is our understanding that the project will consist of single- family residences along with various associated site improvements. It is our understanding that the proposed residences will be of relatively lightweight wood -frame construction and will be supported by conventional shallow spread footings and concrete slabs on grade. The associated improvements will include paved roadways, concrete walkways, patios, driveways, landscape areas and various underground utilities. The majority of the subject site is presently vacant and the ground surface is covered with scattered desert brush, short grass and weeds. Large tamarisk trees exist along the majority of the property lines. The majority of the property has apparently been previously used for agricultural purposes. The property has been leveled throughout and is near the elevation of the adjacent properties and roadways. The Griffin estate located within the central portion of the property is not a part of the proposed project. The eastern portion of the Griffin estate including a horse racing track and fields are a part of the proposed development. The PGA West development forms the southern site boundary and exists west of the site across Madison Street. There is a residential subdivision along the southeastern edge of the site. The properties along the northeast property boundary and north of the site across Avenue 54 remain vacant. Sladden Engineering August 17, 2004 -2- Project No. 544-4402 04-08-571 Based upon our previous experience with lightweight residential structures, we expect that isolated column loads will be less than 30 kips and wall loading will be less than to 2.0 kips per linear foot. Grading is expected to include minor cuts and fills to match the nearby elevations and to construct slightly elevated building pads to accommodate site drainage. This does not include removal and recompaction of the bearing soils within the building areas. If the anticipated foundation loading or site grading varies substantially from that assumed the recommendations included in this report should be reevaluated. GEOLOGY AND SEISMICITY The project site is located within the central Coachella Valley that is part of the broader Salton Trough geomorphic province. The Salton Trough is a northwest trending depression that extends from the Gulf of California to the Banning Pass. Structurally the Salton Trough is dominated by several northwest trending faults, most notable of which is the San Andreas system. A relatively thick sequence of sedimentary rocks have been deposited in the Coachella Valley portion of the Salton Trough from Miocene to present times. These sediments are predominately terrestrial in nature with some lacustrian and minor marine deposits. The mountains surrounding the Coachella Valley are composed primarily of Precambrian metamorphic and Mesozoic granitic rock. The Coachella Valley is situated in one of the more seismically active areas of California. The San Andreas fault zone is considered capable of generating a maximum credible earthquake of magnitude 8.0 and due to its proximity to the project site the distance of approximately 9.9 kilometers should be considered in design fault for the project. Seismic activity along the nearby faults continues to affect the area and the Coachella Valley is considered one of the more seismically active regions in California. A computer program and pertinent geologic literature were utilized to compile data related to earthquake fault zones in the region and previous seismic activity that may have affected the site. E.Q. Fault Version 3.00 (Blake) provides a compilation of data related to earthquake faults in the region. The program searches available databases and provides both distances to causitive faults and the corresponding accelerations that may be experienced on the site due to earthquake activity along these faults. The attenuation relationship utilized for this project was based upon Joyner & Boore (1987) attenuation curves. The information generated was utilized in our liquefaction evaluation The site is not located in any Earthquake Fault zones as designated by the State but is mapped in the County's Liquefaction and Ground Shaking Hazard Zone V. Several significant seismic events have occurred within the Coachella Valley during the past 50 years. The events include Desert Hot Springs - 1948 (6.5 Magnitude), Palm Springs - 1986 (5.9 Magnitude), Desert Hot Springs - 1992 (6.1 Magnitude), Landers -1992 (7.5 Magnitude) and Big Bear -1992 (6.6 Magnitude). Sladden Engineering August 17, 2004 -3- Project No. 544-4402 04-08-571 SUBSURFACE CONDITIONS The soils underlying the site consist primarily of fine-grained silty sands with scattered generally thin sandy clayey silt layers. As is typical for the area, the silty sand and sandy silt layers are inconsistently interbedded and vary in thickness. Silty sands were the most prominent soils within our exploratory borings but several prominent sandy silt and clayey silt layers were also encountered. The silty sands encountered near the existing ground surface appeared somewhat loose but the deeper silty sand and sandy silt layers appeared relatively firm. Sampler penetration resistance (as measured by field blowcounts) indicate that density generally increases with depth. The site soils were dry on the surface but moist below a depth of approximately 5 feet. Laboratory testing indicates that the surface soils within the upper 5 feet consist primarily of silty sands. Expansion testing indicates that the surface silty sands are generally non -expansive and are classified as "very low" expansion category soils in accordance with Table 18-I-B of the 1997 Uniform Building Code. Groundwater was not encountered within our borings that extended to a depth of approximately 50 feet below the existing ground surface. Groundwater should not be a factor in design or construction. LIQUEFACTION Liquefaction occurs with sudden loss of soil strength due to rapid increases in pore pressures within cohesionless soils as a result of repeated cyclic loading during seismic events. Several conditions must be present for liquefaction to occur including; the presence of relatively shallow groundwater, generally loose soils conditions, the susceptibility of soils to liquefaction based upon grain -size characteristics and the generation of significant and repeated seismically induced ground accelerations. Liquefaction affects primarily loose, uniform grained cohesionless sands with low relative densities. In the case of this project site, several of the factors required for liquefaction to occur are absent. As previously indicated, groundwater was not encountered within our borings that extended to a depth of approximately 50 feet below the existing ground surface on the site. Due to the depth to groundwater, the potential for liquefaction affecting the site is considered. negligible. CONCLUSIONS AND RECOMMENDATIONS Based upon our field investigation and laboratory testing, it is our opinion that the proposed residential development is feasible from a soil mechanic's standpoint provided that the recommendations included in this report are considered in building foundation design and site preparation. Due to the somewhat loose condition of the surface soils, remedial grading is recommended for the building areas. We recommend that remedial grading within the proposed building areas include the overexcavation and recompaction of the primary foundation bearing soils. Specific recommendations for site preparation are presented in the Site Grading section of this report. Sindden Engineering August 17, 2004 -6- Project No. 544-4402 04-08-571 Soluble Sulfates: The soluble sulfate concentrations of the surface soils have not yet been determined but native soils in the area have been known to be potentially corrosive with respect to concrete. The use of Type V cement and specialized sulfate resistant concrete mix designs may be necessary for concrete in contact with the native soils. Tentative Pavement Design: All paving should be underlain by a minimum compacted fill thickness of 12 inches (excluding aggregate base). This may be performed as described in tie Site Grading Section of this report. R-Value testing was not conducted during our investigation but based upon the sandy nature of the surface soils, an R-Value of approximately 50 appears appropriate for preliminary pavement design. The following preliminary onsite pavement section is based upon a design R-Value of 50. Onsite Pavement (Traffic Index = 5.0) Use 3.0 inches of asphalt on 4.5 inches of Class 2 base material Aggregate base should conform to the requirements for Class 2 Aggregate base in Section 26 of CalTrans Standard Specifications, January 1992. Asphaltic concrete should conform to Section 39 of the CalTrans Standard Specifications. The recommended sections should be provided with a uniformly compacted subgrade and precise control of thickness and elevations during placement, Pavement and slab designs are tentative and should be confirmed at the completion of site grading when the subgrade soils are in -place. This will include sampling and testing of the actual subgrade soils and an analysis based upon the specific traffic information Shrinkage and Subsidence: Volumetric shrinkage of the material that is excavated and replaced as controlled compacted fill should be anticipated. We estimate that this shrinkage could vary from 20 to 25 percent. Subsidence of the surfaces that are scarified and compacted should be between 0.1 and 0.3 tenths of a foot. This will vary depending upon the type of equipment used, the moisture content of the soil at the time of grading and the actual degree of compaction attained. These values for shrinkage and subsidence are exclusive of losses that will occur due to the stripping of the organic material from the site and the removal of oversize material. General Site Grading: All grading should be performed in accordance with the grading ordinance of the City of La Quinta, California. The following recommendations have been developed on the basis of our field and laboratory testing and are intended to provide a uniform compacted mat of soil beneath the building slabs and foundations. 1. Site Clearing: Proper site clearing will be very important. Any existing vegetation, slabs, foundations, abandoned underground utilities or irrigation lines should be removed from the proposed building areas and the resulting excavations should be properly backfilled. Soils that are disturbed during site clearing should be removed and replaced as controlled compacted fill under the direction of the Soils Engineer. Sladden Engineering August 17, 2004 -7- Project No. 544-4402 04-08-571 2. Preparation of Building and Foundation Areas: In order to provide adequate and uniform bearing conditions, we recommend overexcavation throughout the proposed residential building areas. The building areas should be overexcavated to a depth of at least 3 feet below existing grade or 2 feet below the bottom of the footings, whichever is deeper. The exposed soils should then be scarified to a depth of 1-foot, moisture conditioned and recompacted to at least 90 percent relative compaction. The excavated material may then be replaced as engineered fill material as recommended below. 3. Placement of Compacted Fill: Within the building pad areas, fill materials should be spread in thin lifts, and compacted at near optimum moisture content to a minimum of 90 percent relative compaction. Imported fill material shall have an Expansion Index not exceeding 20. The contractor shall notify the Soils Engineer at least 48 hours in advance of importing soils in order to provide sufficient time for the evaluation of proposed import materials. The contractor shall be responsible for delivering material to the site that complies with the project specifications. Approval by the Soils Engineer will be based upon material delivered to the site and not the preliminary evaluation of import sources. Our observations of the materials encountered during our investigation indicate that compaction within the native soils will be most readily obtained by means of heavy rubber tired equipment and/or sheepsfoot compactors. A uniform and near optimum moisture content should be maintained during fill placement and compaction. 4. Preparation of Slab and Paving Areas: All surfaces to receive asphalt concrete paving or exterior concrete slabs -on -grade, should be underlain by a minimum compacted fill thickness of 12 inches. This may be accomplished by a combination of overexcavation, scarification and recompaction of the surface, and replacement of the excavated material as controlled compacted fill. Compaction of the slab and pavement areas should be to a minimum of 90 percent relative compaction. 5. Testing and Inspection: During grading tests and observations should be performed by the Soils Engineer or his representative in order to verify that the grading is being performed in accordance with the project specifications. Field density testing shall be performed in accordance with applicable ASTM test standards. The minimum acceptable degree of compaction shall be 90 percent of the maximum dry density as obtained by the ASTM D1557-91 test method. Where testing indicates insufficient density, additional compactive effort shall be applied until retesting indicates satisfactory compaction. Sadden Engineering August 17, 2004 -8- Project No. 544-4402 04-08-571 GENERAL The findings and recommendations presented in this report are based upon an interpolation of the soil conditions between boring locations and extrapolation of these conditions throughout the proposed building area. Should conditions encountered during grading appear different than those indicated in this report, this office should be notified. This report is considered to be applicable for use by Trans West Development, Inc. for the specific site and project described herein. The use of this report by other parties or for other projects is not authorized. The recommendations of this report are contingent upon monitoring of the grading operations by a representative of Sladden Engineering. All recommendations are considered to be tentative pending our review of the grading operations and additional testing, if indicated. If others are employed to perform any soil testing, this office should be notified prior to such testing in order to coordinate any required site visits by our representative and to assure indemnification of Sladden Engineering. We recommend that a pre -job conference be held on the site prior to the initiation of site grading. 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 grading performed. Sladden Engineering August 17, 2004 -9- Project No. 544-4402 04-08-571 REFERENCES ASCE Journal of Geotechnical Engineering Division, April 1974. Boore, Joyner and Fumal (1994) Estimation of Response Spech•a and Peak Accelerations fronn North American EmIliquakes, U. S. Geological Survey, Open File Reports 94-127 and 93-509. Finn, W. E. Liam, (1996) Evaluation of Liquefaction Potential for Different Earthquake Magnihndes and Site Conditions, National Center for Earthquake Engineering Research Committee. Joyner and Boore, (1988) Measurements, Characterization and Prediction of Strong Ground Motion, ASCE Journal of Geotechnical Engineering, Special Publication No. 20. Lee & Albaisa (1974) "Earthquake Induced Settlenients in Saturated Sands". Seed and Idriss (1982) Ground Motions and Soil Liquefaction During Earthquakes, Earthquake Engineering Research Institute Monograph. Seed, Tokimatsu, Harder and Chung, (1985), Influence of SPT Procedures in Soil Liquefaction Resistance Evaluations, ASCE Journal of Geotechnical Engineering, Volume 111, No.12, December. Rogers, Thomas I -I., Geologic Map of California, Santa Ana Map Sheet. Riverside County, 1984, Seismic Safehj Elennennt of the Riverside County General Plan Sladden Engineering APPENDIX A Site Plan Boring Logs APPENDIX A FIELD EXPLORATION For our field investigation, 16 exploratory borings were excavated on July 16 and August 4, 2004, using a truck mounted hollow stem auger rig (Mobile B-61) in the approximate locations indicated on the site plan included in this appendix. Continuous log of the materials encountered were prepared on the site by a representative of Sladden Engineering. Boring logs are included in this appendixP,'' ,�k Representative undisturbed samples were obtained within oe P-ha by drivir gla .thin -Walled steel penetration sampler (California split spoon sampler) or a Standard Penetration Test (SM"mpler with a 140 pound hammer dropping approximately 30 inches (ASTM D1586). The number of blows required to drive the samplers 18 inches was recorded (generally in 6 inch increments). Blowcouhts are indicated on the boring log. The California samplers are 3.0 inches in diameter, carrying brass sample rings having inner diameters of 2.5 inches. The standard penetration samplers are 2.0 inches in diameter with an inner diameter of 1.5 inches. Undisturbed samples were removed from the sampler and placed in moisture sealed containers in order to preserve the natural soil moisture content. Bulk samples were obtained from the excavation spoils and samples were then transported to our laboratory for further observations and testing. Griffin Ranch SEC Avenue 54 and Madison Street Date: 7/16/2004 Borijim No. 1 Job Number: 544_4402 Cl) \ CQ C o 30 Y G A O V im Description va ° Remarks 0 _ 1 illative Soils 5 3/518 Dry Silty Fine Sand SM 5 - Grey in color i - i i 10 y _ t 4/8/11 Dry Fine to Medium Sand with Traces of Silt SM 1 7 Grey in color 15 2/6/7 Dry Silty Fine Sand SM 1 --- Gray in color 20 3/5/7 Dry Silty Fine Sand SM 1 l 1 Grey in color 25 1 315/6 Clayey Silt ML I 67 Firmly Packed Grey in color 30 314/7 Clayey Silt ML i 69 Grey in color 35 5/6/9 Slil;latly moist Clayey Silt with Traces of Fine Sand ML I5 79 Grey in color 40 3/5/13 Slightly moist Clayey Silt with Traces of Fine Sand ML 4 69 1 Grey in color - w i1h a Layer of Silty Fine Sand --4" _ Note- The stratification lines 45 6191! 7 Slightly Moist Silty) inc Sand SM 4 represent the approximate - - boundaries between the soil i' types; the transition may be _ Gradual. " r 50 : 4 9115124 S1i ltit Moist i! Fine -and SM 3 14 Total Dcptl> _ —50' Groundwater not encountered 13edmek not encountered Sladden Engineering Griffin Ranch SEC Avenue 54 and Madison Street Pate.: 7/16/2004 Boring No. 2 Job Number: 544-4402 a N a� O O • •- O q rq U m Description to Remarks 0 Native Soils 5 6/10/13 Firm Clayey Silt ML 7 — Grey in color 10 3/4/6 Clayey Silt with Silty Fine Sand Layer —6" ML 6 77 Grey in color 15 5/6/6 Dry Sandy Silt ML 3 71 Grey in color 20� Grey in color 4/6/8 Dry Silty Fine Sand SM 2 -- _ .. II 25° 3/6/11 Silty Medium to Coarse Sand SM 19 --- Grey in color Mi 30 4/6/7 Silty Fine Sand SM 19 — Grey in color 35 '; i` 4/5/6 Silty Fine Sand with Firm Sandy Silt Layer --5" SM 5 --- Grey in color Note: 711e stratification lines represent the approximate boundaries betwcen the soil types; 40 ;;:.'' Oc 3/5l7 Silty Fine Sand SM 3 13 the transition may be gradual. 45 .1 ' 4/5/4 Moist Silty Fine to Medium Sand with a very Moist SM 19 -- Grey in color d Sana Layer —6" Y and Clayey Silt LaY Total Depth = --50' .;., Groundwater encountered 50' 50 '',? 3/6/9 W� Sandyand Clav Silt with Slitv Fine Sand SM 24 26 Bedrock not encountered Sladden Engineering Griffin Ranch -- SEC Avenue 54 and Madison Street Ante: 7/16/2004 Baring No. 3 Job Numben 544-4402 NO a 7t ~ D A sn Cg r� p: Remarks 0 i {; J� Surrounding Area is Flood Irrigated 5 3/3/5 i< nisi. Silty Fine to Medium Sand SM 113 4 17 Greyin color r s 10 'r 4/5/6 ikloist Silty Finc Sand SM 6 21 Grey in color _ e h 4 �9[ Grey in color 15 1/l/I Wet Clayey Silt Layer—l0" ML 34 84 20 2/2/2 West Clayey Silt Layer —10" with Silty Fine Sand ML 27 71 Grey in color Grey in color 25 '_' 3/3/6 Moist Silty Fine to Medium Sand with a Clayey Silt SM 19 "-- Layer -611 Grey in color 30 3/2/20115 Moist Silty Any Layer--16" CL 35 89 ,fxfiK 35 €: Grey in color 51719 Moist Fine to Medium Sand wilh Trnccs of'Silt SP 6 10 " Note: The stratification lines represent the approximate 40 5/8/11 Moist Fine to Medium Sand with Traces of Silt SP 4 7 boundaries between the soil _ types; the transition may be gradual, 45 6/10/16 Moist Fine to Medium Sand with Traces of Silt SP 5 8 Grey in color Total Depth = —50' Bedrock not encountered 50 = `: 9/9/l7 Moist Fine to Medium Sand with Traces of Silt SP 9 16 Gmundwater not encountered Sladden Engineering Date: 7/16/2004 © 0 ys` � l - 1 Uj iflin Ranch SEC Avenue Sa and Madison Street Boring No. 4 Job Number: u ; iif.errinein.. n c O 5 IF: 4/7/9 Dry Silty Fine Sand t 10 3/7/10 .Dante Silty Fine Sand i 15 213/7 20 2/3/4 25 Wct Silty Clay and and Clayey Silt 30 Recovered Sample Unrmovered Sample I Standard Penetration Sample 35 ' 40 45 50 Sand Note: The stratification lines represent the approximate boundaries between the soil types; the transition may be 544-4402 ]MU6 Cray in color Grcy in color Grey in color ML in color Depth = —20, ck not encountered d►vatcr not encountered Sladden Engineering Griffin Ranch SEC Avenue 54 and Madison Street Tate: 8/4/2004 Boring No. 5 Job Number: 544-4402 O u W, v3 I O w U C4 Description M remarks 0 !dative Soils 2 5 3/12/23 Dry Silty Clay CL 2 93 Greyish Brown in color 10 i 9/11124 Dry Fine to Medium Sand with Traces of Silt SP i 7 Grey in color l5 14/15127 Dry Clayey Silt ML 4 89 Grey in color 20 :IR .:'. 17YSO-611 Dryi ty Fine an 1 1 12Gre in color Total Depth =--20' _ Bedrock not encountered 25 Groundwater of encountered 30 _ Recovered Sample I Unrecovered Sample - Standard Penetration Sample 35 40 Note: The stratification lines represent the approximate _ boundaries between the soil types; the transition may be gradual. 45 50 Sladden Engineering Griffin Ranch SEC Avenue 54 and Madison Street Date: 8/4/2004 -- Boring No. 6 Job Number: 544-4404. r © a Description Remarks 0 Es Native Soils _ T 5 19/30/32 Dry Silty Fine Sand SM 1 -- Grey in color 10 €=€i` 10/23/20 Dry Fine Sand with Truces of Silt 5F I Greyishbrown in color 1 1 I5 ry ty me San wit t a la e t t Layer SM L6, Grey in color - Total Depth =-15' " 13cdrock not eneounered Groundwater not encountered 20 25 30 Recovered Sample - Unrecovered Sample - Standard Penetration Sample 35 40 Note: The stratification lines represent the approximate - boundaries between the soil types; the transition may be - ii�cluai. 45 50 Sladden Engineering Griffin Ranch SEC Avenue 54 and Madison Street Matte: 8/4/2004 Boring No. 7 Job Number: 5 4-4402 U � CO � d7 0 1 q v� U m Description rn0 a Retntjrlcs 0 r Native Soils 7 4t. 5 F? 5110115 Dry Silty Fine Sand SM 0 -- Grey in color i 10 6/10/19 Dry Silty Fine Sand SM 2 22 Grey in color _ t Grey in color Grey in color 15 9126/24 Dry Clayey Silt ML 6 81 20 8/11/15 DrySilty Sand67 Total Depth = —20' - Bedrock not encountered 25 Recovered Sample. Groundwater not encountered - Unrecovered Sample - Standard Penetration Sample 30 35 Note: The stratification lines represent the approximate - boundaries between the soil types; the transition may be - gradual, 40 45 50 Sladden Engineering Griffin Ranch SEC Avenue 54 and Madison Street Date: 8/4/2004 Boring No. 8 Job Number: 544_4402 rn A rn U W Description rn 5 ° a Remnrks tl it t,t T. a'Ads X' Native Soils I 5 10/33150-6" Dry Silty Fine Sand SM 1 --- Grey in color fl? 10 f;t i : 16/22/30 Dry Silty Fine Sand SM 1 11 Grey in solar 15 ; �• 14/22/26 Dry Silty Fine Sand with Traces of Cla SM 4 35 Greyish Brown in color 20 Total Depth -- 15' Bedrock not encountered Groundwater not encountered - Recovered Sample 25 I - _ Unrecovered Sample I - Standard Penetration Sample 30 Note: The stratification lines represent the approximate 35 boundaries between the soil types; the transition may be gradual. 40 45 50 Sladden Engineering Griffin Ranch SEC Avenue 54 and Madison Street Date: 8/4/2004 Baring_No. 9 Job Number: 544-440 Cn q, U pq Descri lion V3 a o Remarks p 71Native Soils 5 8/14/30 Slightly Moist Silty Clay and Silty Fine Sand CL 10 92 Greyish Brown in color 10 ': Brown in color 22/22/50-6" Slightly Moist Fine to Medium Sand with Traces of Silt SP 2 11 15 Brown in color 15120/22 1 Fine Sandy Sit wit Traces of Clay I ML 1 6 1 11Greyish - Recovered Sample Total Depth —15' _ I Bedrock not encountered 20 Unrecovered Sample Groundwater not encountered - Standard Penetration Sample 25 30 - Note: The stratification lines represent the approximate - boundaries between the soil types; the transition may be - gradual. 35 40 45 50 Sladden Engineering Griffin Ranch SEC Avenue 54 and Madison Street Date: 8/4/204 Boring No. 10 Job Number: 544-4402 a e C) r•� ° ° a a Gi rI] U Description rn o Remarks 0 Native Soils 5 9/11/I2 Dry Fine Sand with Traces of Silt SP 2 --- Grey in color 10 11/7/13 Dry Fine Sand with Traces of Silt SP 1 17 Grey in color 15 7/10/16 Dry Fine Sand with Traces of Silt SP 1 15 Grcy in color 20 grey in color /I /14 IDryClaycy i t 3 68 - Recovered Sample 'Total Depth = —20' 25 I (Bedrock not encountered - Unrecovered Sample Groundwater not encountered - Standard Penetration Sample 30 35 - Note: The stratification lines represent the approximate _ boundaries between the soil types; the transition may be - gradual. 40 45 50 Sladden Engineering Griffin Ranch SEC Avenue 54 and Madison Street Date: 8/4/2004 BoHng No. 11 Job Number: 5444402 4. 0 m G AU CO Description rn t 4 Remarks 0 Native Soils 5 5/8/13 Slightly Moist Fine to Medium Sand with Trace Silt SP 1 9 Grey in color 10 €' 4/6/9 Slightly Moist Fine to Medium Sand with Trace Silt SP 4 --- Greyish Brown in color - and a Sandy Silt Layer-6" 1.5 s':'': 5/9/12 Moist Fin, Sand with Traces of Silt SP IL 2 14 IlGrey in color - Recovercd Sample Total Depth =- i 5' _ I Bedrock not encountered 20 1Snrecovered Sample I i3mundwaternot encountered _ - Slandard Penetration Sample 25 30 35 _ Note: The stratification lines represent the approximate _ boundaries between the soil types; the transition maybe gradual. 40 45 50 Sladden Engineering Griffin Ranch SEC Avenue 54 and Madison Street Date: 8/4/2004 Boring No.12 Job Number: 544-4402 � a A v, g v Description ° Remarks 0 >. . 4, '� Native Soils 5 ! 4/6/8 Moist Silty Pine Sand SM 3 - - i0rey in color q}. ,. 4/3/4 Wet Silty Clay Layer —5" and Sandy Silt ML 1 85 10 .Dark Grey in color 15 Dark Grey in color 2/2/3 Wet Silty Clay CL I93 Recovered Sample total Depth —15' _ I (Bedrock not encountered 20 Unrecwvered Sample I groundwater not encountered _ -EIIEStandard Penetration Sample 25 30 _ Note: The stratification lines represent the approximate _ boundaries between the soil types; the transition may be _ gradual. 35 40 45 SO Sladden Engineering Griffin Ranch SEC Avenue 54 and Madison Street Date: 8/4/2004 Boi-Mg No.13 Job Number: 5i4-4402 p 0 o k p vs U t0 DescriLion r° `" a Remarks 0 iF Native Soils 5 ; ' 5/5/6 Moist Silty Fine Sand SM 6 26 Grey in color _ ks i 10 30 87 Dark Grey in color 5/5/10 Wet Clayey Silt ML 15 13 --- Dark Orcy in color 2/3/6 Wet Silty Fine Sand with Traces of Clay SM - Recovered Sample Total Depth 3--15' IBedrock not encountered 20 Unrecovered Sample I Groundwater not encountered - _ Standard Penetration Sample 25 30 _ Notw. The stmtification lines represent the approximate - boundaries between the soil types; the transition may be 35 t;r;AtIal. 40 45 50 Sladden Engineering Griffin Ranch SEC Avenue 54 and Madison Street Date: 8/4/2004 Boring No.14 Job Number: 544-4402 U �LI e 0 N � G qU pq Description �, Remarks 0 Native Soils 5 �3 ` 6/10112 Dry Silty Fine Sand with a Clayey Silt Layer-6" SM 13 - Light Greyish Brown in color 5 10 7/16116 Dry Silty Fine Sand SM 1 Grey in color i 9/16/20 ISIi,Shtly Moist Silty Fine Sand I SM IL I i I--- G14 y in color - Recovered Sample -Total Depth —15' - I Bedrock not encountered 20 Unrecovered Sample I Groundwater not encountered _ - Standard Penetration Sample 25 30 Note: The stratification lines represent the approximate _ boundaries between the soil types; the transition may be 35 gradual. 40 45 50 Sladden Engineering . Griffin Ranch SEC Avenue 54 and Madison Street Date: 8/4/2004 Boring No.15 Job Number; 544-4402 0 p v, Op U pq Description U) p p a Remarks 0 1 ii Native Soils +v 5 i 5/5/7 Slightly Moist Silty Fine Sand SM 3 13 Grey in color 10 + i 4/5/8 Silty Fine Sand with Traces of Clay SM 15 36 Light Greyish Brown in color 15 r 5/6113 Silty Fine Sand with a Clayey Silt Layer —5" SM 4 --- Grey in color - Recovered Sample Total Depth —15' _ f Bedrock not encountered 20 Unrecovered Sample I Groundwater not encountered _ - Standard Penetration Sample 25 30 - Note: The stratification lines represent the approximate boundaries between the soil types; the transition may be _ gradual. 35 40 45 50 Sladden Engineering Griffin Ranch SEC Avenue 54 and Madison Street Date: 8/4/2004 Boring No.16 Job Number: 5444402 o 0 C. � O y 3 va o U 0 Description 0 rn p p Remarks 0 :� r.; ;•,�i�� Native Soils ' I ��y S w ! 4/6/7 Silty Fine Sand with a Clayey Silt Layer—Y SM 10 22 Grs y in color k� 10 3 ;`` 3/618 Slightly Moist Silty Fine Sand with Traces of Clay SM 9 36 Grey in color j";k l5 ! 4/8/13 Silty Fine to Medium Sand SM 2 25 Grey in color - Recovered Sample 'Total Depth =-.15' - I Bedrock not encountered 20 Unrecovered Sample I Groundwater not encountered _ - Standard Penetration Sample 25 30 - Note: The stratification lines represent the approximate 35 boundaries between the soil types; the trnnsition may be - gradual. 40 45 50 Siadden Engineering APPENDIX B Laboratory Testing Laboratory Test Results APPENDIX B Representative bulk and relatively undisturbed 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 underlying 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 testing. This testing including consolidation, shear strength and expansion testing was performed in order to provide a means of developing specific design recommendations based on the mechanical properties 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 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 Log. Maximum Density -Optimum Moisture Determinations: Representative soil types were selected for maximum density determinations. This testing was performed in accordance with the ASTM Standard D1557-91, Test Method A. The results of this testing are presented graphically in this appendix. The maximum densities are compared to the field densities of the soil in order to determine the existing relative compaction to the soil. This is shown on the Boring Log, and is useful in estimating the strength and compressibility of the soil. Classification Testing: Soil samples were selected for classification testing. This testing consists of mechanical grain size analyses and Atterberg Limits determinations. These provide information for developing 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. SOIL MECHANIC'S TESTING Direct Shear Testing One bulk sample was selected for Direct Shear Testing. 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 800 to 2300 pounds per square foot. Expansion Testing: One bulk sample was 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. Consolidation Testing: Pour relatively undisturbed samples were selected for consolidation testing. For this testing one -inch thick test specimens are subjected to vertical loads varying from 575 psf to 11520 psf applied progressively. The consolidation at each load increment was recorded prior to placement of each subsequent load. The specimens were saturated at the 575 psf or 720 psf load increment. Project Number: Project Name: Lab ID Number: Sample Location: Description: Maximum Density: Optimum Moisture: 145 140 135 130 A t20 110 105 1004 0 Maximum Density/Optimum Moisture ASTM D698/D1557 544-4402 Trans West Housing Bulk 3 @ 0-5- Silty Sand 129 pcf 9.5% Sieve Size % Retained 3/4" 3/8" #4 0.0 5 10 15 Moisture Content, % August 3, 2004 ASTM D-1557 A Rammer Type: Manual 20 25 Max Density Sladden Engineering Revised 12/03/02 Project Number: Project Name: Lab ID Number: Sample Location: Description: Maximum Density: Optimum Moisture: G 120 115 110 105 100 + 0 Maximum Density/Optimum Moisture ASTM D698/D1557 544-4402 Ave. 54 & Madison Bulk 3 @ 0-5' Silty Sand 119 pef 10.5% Sieve Size % Retained 3/4" 3/8" #4 0.0 Zero Air Voids Lines, sg --2.65, 2,70, 2,75 5 10 15 Moisture Content, % August 30, 2004 ASTM D-1557 A Rarnmer Type: Manual 20 25 Max Density Sladden Engineering Revised 12/03/02 Gradation ASTM C1 17 & C136 Project Number: 544-4402 Project Naive: Trans West Housing Sample ID: Bulk 3 @ 0-5' Sieve Sieve Percent Size, in Size, mm Passing 1 " 25.4 100.0 3/V 19.1 100.0 1/2" 12.7 100.0 3/8" 9.53 100.0 #4 4.75 100.0 #8 2.36 100.0 #16 1.18 97.0 #30 0.60 94.0 #50 0.30 86.0 #100 0.15 75.0 #200 0.074 25.0 August 3, 2004 , 'uiUNS ui l�immm� �Cou�iuE �ME 1111 Ii HIM mm III 1111 Ilium I I I MINE I III 0 m fills ME HIM lllommmi MEMO 'ME liiilmmmiiiillm■ 11 NINE ME JIMEM ion■■gymlow 0= mmnu■mm 111 NINE= 11 liimm mmil mm �s■ lnimmmli inommiillll 11011111 If off off oil Gradation Sladden Engineering Revised 11/20/02 Gradation ASTM C117 & C136 Project Number: 544-4402 Project Name: Ave. 54 & Madison Sample ID: Bulk 3 @ 0-5' Sieve Sieve Percent Size, in Size, mm Passing 1" 25.4 100.0 3/4" 19.1 100.0 1/2" 12.7 100.0 3/8" 9.53 100.0 #4 4.75 100.0 #8 2.36 99.0 #16 1.18 91.0 #30 0.60 86.0 #50 0.30 71.0 #100 0.15 61.0 #200 0.074 25.0 August 30, 2004 liingmmi I im lowinnommullmolm 11011111111111 RR min 0 111 11 i0 NINE= ii� � "Willi lignmill01 INE11111111111111 in, vmni��u � 111111101311 Ill i■nun■�■��� ��I�■�s liv 1l1N1UUW1HU If IN1 I Gradation Sladden Engineering Revised 11/20/02 Job Number: Job Name: Lab ID: Sample ID: Soil Description: Expansion Index ASTM D 4829/UBC 29-2 544-4402 Date: 8/3/2004 Trans West Housing Tech: Jake Bulk 3 @ 0-5' Siltv Sand Wt of Soil + Ring-, 595.0 Weight of Ring: 179.0 Wt of Wet Soil: 416.0 Percent Moisture: 1 8% Wet Deng cf. 126.0 Dry Densti , pef, 1 116.7 Saturation: 1 48.7 Expansion Rack # Date/Time 8/4/2004 9:00 AM. Initial Reading 0.500 Final Reading 0.511 Expansion Index (Final - Initial) x 1000 11 E1 Sladden Engineering Revised 12/10/02 One Dimensional Consolidation ASTM D2435 & D5333 Job Number: 544-4402 Job Name: Ave. 54 & Madison Sample ID: Boring 9 @ 5' Soil Description: Sandy Silt -3 -4 -5 -6 -7 -9 -10 0.0 August 30, 2004 Initial Dry Density; pc£ 88.0 Initial Moisture, %: 10 Initial Void 0.894 Specific Gravity: 2.67 % Change in Height vs Normal Presssure Diagram —e—Before Saturation —A After Saturation s r --e--Rebound --f—Hydro Consolidation 1.0 2.0 3.0 4.0 5.0 6.0 7.0 Consolidation Sladden Engineering Revised 11/20/02 One Dimensional Consolidation ASTM D2435 & D5333 Job Number: 544-4402 Job Name: Ave. 54 & Madison Sample ID: Boring 9 @ 10' Soil Description: Sand 1 0 -1 -2 -3 -4 -5 -6 -7 -8 -9 -10 0.0 August 30, 2004 Initial Dry Density, pcf: 99.9 Initial Moisture, %: 2 Initial Void Ratio: 0.669 Specific Gravity: 2.67 % Change in Height vs Normal Presssure Diagram --0 Before Saturation - —After Saturation —e— Rebound --*—Hydro Consolidation 1.0 2.0 3.0 4.0 5.0 6.0 7.0 Consolidation Sladden Engineering Revised 11/20/02 Expansion Index ASTM D 4829/UBC 29-2 Job Number: 544-4402 Job Name: Ave. 54 & Madison Lab ID: Sample ID: Bulk 3 @ 0-5' Soil Description: Silty Sand Wt of Soil + Ring: 585.0 Weight of Ring: 179.0 Wt of Wet Soil: 406.0 Percent Moisture: 9% Wet Density, pcf: 123.0 Dry Denstiy, pcf 112.9 Saturation: 1 49.3 Expansion Rack # Date/Time 8/30/2004 9:00 AM Initial Reading 0.500 Final Reading 0.502 Expansion Index (Final - Initial) x 1000 2 Date: 8/30/2004 Tech: Jake El Sladden Engineering Revised 12/10/02 Gradation ASTM C117 & C136 Project Number: 544-4402 Project Name: Ave. 54 & Madison Sample ID: Boring 3 @ 5' Sieve Sieve Percent Size, in Size, mm Passing 111 25.4 100.0 3/4" 19.1 100.0 1/2" 12.7 100.0 3/8" 9.53 100.0 #4 4.75 100.0 #8 2.36 100.0 #16 1.18 97.0 #30 0.60 79.0 #50 0.30 68.0 #100 0.15 59.0 #200 0.074 17.0 August 30, 2004 INN IEEE IU1100111 1111111 INN Ulm 11 111 Rings am IN IS I Ing MIMI I Mimi HE 1111 1110MU1111 iageiiii I I NMI" NEE Imes 0 111111 1 1 NEW linom 0 so lignm� IN SO so [HIRE ln�mniiiisom ON NNE ON H IN WIN! I m I ME 111 1 long= I IN NO MIUIII mill I== III Gradation Sladden Engineering Revised 11120/02 Gradation ASTM Cl 17 & C136 Project Number: 544-4402 August 30, 2004 Project Name: Ave. 54 & Madison Sample ID: Boring 3 @ 10' Sieve Sieve Percent Size, in Size, mm Passing 1" 25.4 100.0 3/4" 19.1 100.0 1/2" 12.7 100.0 3/8" 9.53 100.0 #4 4.75 100.0 #8 2.36 100.0 #16 1.18 100.0 430 0.60 86.0 950 0.30 74.0 #100 0.15 57.0 #200 0.074 21.0 ro. liiiam WE IN IS in vim IN Ili Rl ME I MEN ION lllin 011111111111111 1 UNION H �U lllimm-lill go 1111110 Ion OMNI 11 NE #I oil Gradation Sladden Engineering Revised 11/20ro2 APPENDIX C 1997 UBC Seismic Design Criteria August 17, 2004 -15- Project No. 544-4402 04-08-571 1997 UNIFORM BUILDING CODE SEISMIC DESIGN INFORMATION The International Conference of Building Officials 1997 Uniform Building Code contains substantial revisions and additions to the earthquake engineering section in Chapter 16. Concepts contained in the updated code that will be relevant to construction of the proposed structures are summarized below. Ground shaking is expected to be the primary hazard most likely to affect the site, based upon proximity to significant faults capable of generating large earthquakes. Major fault zones considered to be most likely to create strong ground shaking at the site are listed below. Fault Zone San Andreas San Approximate Distance From Site Fault Type (1997 UBC) 9.9 km I __ 32.1 km A Based on our field observations and understanding of local geologic conditions, the soil profile type judged applicable to this site is SD, generally described as stiff or dense soil. The site is located within UBC Seismic Zone 4. The Following table presents additional coefficients and factors relevant to seismic mitigation for new construction upon adoption of the 1997 code. Seismic Source Near -Source Acceleration Factor, Na Near -Source Velocity Factor, Nr Seismic Coefficient _ Ca Seismic Coefficient C� San Andreas 1.0 1.2 0.44Na 0.64Nv San Jacinto _ 1.0 1.0 0.44Na 0.64Nv Sladden Engineering