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BRES2018-0086 Geotehnical Reportmeasurements and should be considered approximate. July 25, 2018 Mr. Zeke Coronel Coronel Enterprises, Inc. 42760 Madio Street Indio, CA 92201 Dear Mr. Coronel: i -r n nt in is m_,m a MBE C V-v6 1� " BUILDING DI TORN R bODE 1 COMOLMCE Ill141�1$ EY �� Geotechnical Report APN 773-360-013 La Quinta, California LC[Report No.: LP18112 780 N. 4th Street El Centro, CA 92243 (760) 370-3000 landmark@landmark-ca.com 77-948 Wildcat Drive Palm Desert, CA 92211 (760) 360-0665 gchandra@landmark-ca.com Off cle_ cops RECEIVED OCT 17 2018 CITY OF LA QUINTA DESIGN AND DEVELOPMENITEPARTMENT As per your request, LandMark Consultants, Inc. is providing the following geotechnical report for the proposed 3,156 square foot single family residential project located at 77-137 Casa Del Sol in La Quinta, California. The proposed development will consist of new single family residential home with a garage, concrete driveway and swimming pool. The new home and garage will be one story, wood and metal frame structure with shallow reinforced concrete foundations and slab - on -grade concrete floors. Purpose of Work The purpose of this study was to investigate the upper 14.5 feet of subsurface soil at selected locations within the site for evaluation of physical/engineering properties. From the analysis of the field and laboratory data, professional opinions were developed and are provided in this report regarding geotechnical conditions at this site and the effect on design and construction. Field Exploration Subsurface exploration was performed on June 22, 2018 using a backhoe to excavate two (2) exploratory test pits to an approximate depth of 14.5 feet below the existing ground surface. The test pits locations are shown on the Site and Exploration Plan (Plate A-2). Bulk samples were obtained at selected depths in the test pits. The test pits were Iocated by taped or paced kJ* W APN 773-360-013 — La Quinta, CA LCI Report No. LP18112 A senior engineer maintained logs of the test pits during exploration. The logs were edited in final form after a review of retrieved samples and the field and laboratory data. The test pit logs are presented on Plates B-1 and B-2 in Appendix B. Soils encountered have been classified according to the Unified Soil Classification System. A key to the test pit logs is presented on Plate B-3. The stratification lines shown on the subsurface logs represent the approximate boundaries between the various strata. However, the transition from one stratum to another may be gradual over some range of depth. After logging and sampling the soil, the exploratory test pits were backfilled with the excavated material. The backfill was loosely placed and was not compacted to the requirements specified for engineered fill. Laboratory Testing Laboratory tests were conducted on selected bulk soil samples to aid in classification and evaluation of selected properties of the site soils. The tests were conducted in general conformance to the procedures of the American Society for Testing and Materials (ASTM) or other standardized methods as referenced below. The laboratory testing program consisted of the following tests: • Grain Size Analysis (ASTM D422) — used for soil classification Moisture -Density Relationship (ASTM D1557) — used for soil compaction determinations • Chemical Analyses (soluble sulfates & chlorides, pH, and resistivity) (Caltrans Methods) — used for concrete mix evaluations and corrosion protection requirements The laboratory test results are presented on the subsurface logs and on Plates C-1 through C-3 in Appendix C. Engineering parameters of soil strength, compressibility, and relative density utilized for developing design criteria provided within this report were extrapolated from data obtained from the field and laboratory testing program. LandMark Consultants, Inc. Page 2 APN 773-360-013 — La Quinta, CA LCI Report No. LP18112 Site Conditions The project site is rectangular shaped in plain view, elongated in the east -west direction, and is relatively flat -lying vacant lot. The subject is located on the south side of Casa Del Sol west of Avenida Madero. Both streets are paved two-lane residential streets. Adjacent properties are flat - lying and are approximately at the same elevation with this site. Single-family residences and vacant lots are scattered around the project site. A flood channel is located approximately 200 feet to the northwest. The project site lies at an elevation of approximately 70 to 72 feet above mean sea level (AMSL) in the Coachella Valley region of the California low desert. Annual rainfall in this and region is less than 4 inches per year with four months of average summertime temperatures above 100 'F. Winter temperatures are mild, seldom reaching freezing. Subsurface Soils Subsurface soils encountered during the field exploration conducted on June 22, 2018 consist of dry, medium dense silty sand/sand (SMISP). The near surface soils are non -expansive in nature. The subsurface logs (Plates B-1 and B-2) depict the stratigraphic relationships of the various soil types. Groundwater Groundwater was not encountered in the borings during the time of exploration. According to Coachella Valley Water District (CVWD) readings of groundwater levels from nearby wells, groundwater is located at a depth between approximately 70 and 85 feet below the ground surface in the vicinity of the project site. There is uncertainty in the accuracy of short-term water level measurements. Groundwater levels may fluctuate with precipitation, irrigation of adjacent properties, drainage, and site grading. The groundwater level noted should not be interpreted to represent an accurate or permanent condition. Based on the regional topography, groundwater flow is assumed to be generally towards the north- west within the site area. Flow directions may vary locally in the vicinity of the site. LandMark Consultants, Inc. Page 3 APN 773-360-013 — La Quinta, CA LCI Report No. LP18112 Geologic Setting The project site is located in the Coachella Valley portion of the Salton Trough physiographic province. The Salton Trough is a geologic structural depression resulting from large scale regional faulting. The trough is bounded on the northeast by the San Andreas Fault and Chocolate Mountains and the southwest by the Peninsular Range and faults of the San Jacinto Fault Zone. The Salton Trough represents the northward extension of the Gulf of California, containing both marine and non -marine sediments since the Miocene Epoch. Tectonic activity that formed the trough continues at a high rate as evidenced by deformed young sedimentary deposits and high levels of seismicity. Figure 1 shows the location of the site in relation to regional faults and physiographic features. The surrounding regional geology includes the Peninsular Ranges (Santa Rosa and San Jacinto Mountains) to the south and west, the Salton Basin to the southeast, and the Transverse Ranges (Little San Bernardino and Orocopia Mountains) to the north and east. Hundreds of feet to several thousand feet of Quaternary fluvial, lacustrine, and aeolian soil deposits underlie the Coachella Valley. The southeastern part of the Coachella Valley lies below sea level. In the geologic past, the ancient Lake Cahuilla submerged the area. Calcareous tufa deposits may be observed along the ancient shoreline as high as elevation 45 feet above mean seal level (AMSL) along the Santa Rosa Mountains from La Quinta southward. Lacustrine (lake bed) deposits comprise the subsurface soils over much of the eastern Coachella Valley with alluvial outwash along the flanks of the valley. Faulting The project site is located in the seismically active Coachella Valley of southern California with numerous mapped faults of the San Andreas Fault System traversing the region. We have performed a computer -aided search of known faults or seismic zones that lie within a 44-mile (71 kilometer) radius of the project site (Table 1). A fault map illustrating known active faults relative to the site is presented on Figure 1, Regional Fault Map. Figure 2 shows the project site in relation to local faults. The criterion for fault classification adopted by the California Geological Survey defines Earthquake Fault Zones along active or potentially active faults. LandMark Consultants, Inc. Page 4 APN 773-360-013 — La Quinta, CA LCI Report No. LP18112 An active fault is one that has ruptured during Holocene time (roughly within the last 11,000 years). A fault that has ruptured during the last 1.8 million years (Quaternary time) but has not been proven by direct evidence to have not moved within Holocene time is considered to be potentially active. A fault that has not moved during Quaternary time is considered to be inactive. Review of the current Alquist-Priolo Earthquake Fault Zone maps (CGS, 2000a) indicates that the nearest mapped Earthquake Fault Zone is the San Andreas San Bernardino (South) fault located approximately 8.7 miles northeast of the project site. General Ground Motion Analysis The project site is considered likely to be subjected to moderate to strong ground motion from earthquakes in the region. Ground motions are dependent primarily on the earthquake magnitude and distance to the seismogenic (rupture) zone. Acceleration magnitudes also are dependent upon attenuation by rock and soil deposits, direction of rupture and type of fault; therefore, ground motions may vary considerably in the same general area. CBC General Ground Motion Parameters: The 2016 CBC general ground motion parameters are based on the Risk -Targeted Maximum Considered Earthquake (MCER). The U.S. Geological Survey "U.S. Seismic Design Maps Web Application" (USGS, 2018) was used to obtain the site coefficients and adjusted maximum considered earthquake spectral response acceleration parameters. The site soils have been classified as Site Class D (stiff soil profile). Design spectral response acceleration parameters are defined as the earthquake ground motions that are two-thirds (2/3) of the corresponding MCER ground motions. Design earthquake ground motion parameters are provided in Table 2. A Risk Category H was determined using Table 1604.5 and the Seismic Design Category is D since S, is less than 0.75. The Maximum Considered Earthquake Geometric Mean (MCEG) peak ground acceleration (PGAM) value was determined from the "U.S. Seismic Design Maps Web Application" (USGS, 2018) for liquefaction and seismic settlement analysis in accordance with 2016 CBC Section 1803.5.12 and CGS Note 48 (PGAM = FPGa*PGA). A PGAm value of 0.52g has been determined for the project site. LandMark Consultants, Inc. Page 5 APN 773-360-013 — La Quinta, CA LCI Report No. LP18112 Seismic and Other Hazards ► Groundshaking. The primary seismic hazard at the project site is the potential for strong groundshaking during earthquakes along the San Andreas Fault. A further discussion of groundshaking follows above. ► Surface Rupture. The project site does not lie within a State of California, Alquist-Priolo Earthquake Fault Zone. Surface fault rupture is considered to be unlikely at the project site because of the well -delineated fault lines through the Coachella Valley as shown on USGS and CDMG maps. However, because of the high tectonic activity and deep alluvium of the region, we cannot preclude the potential for surface rupture on undiscovered or new faults that may underlie the site. P. Liquefaction. Liquefaction is unlikely to be a potential hazard at the site, due to groundwater deeper than 50 feet (the maximum depth that liquefaction is known to occur). Other Potential Geologic Hazards. ► Landsliding. The hazard of landsliding is unlikely due to the regional planar topography. No ancient landslides are shown on geologic maps of the region and no indications of landslides were observed during our site investigation. ► Volcanic hazards. The site is not located in proximity to any known volcanically active area and the risk of volcanic hazards is considered very low. ► Tsunamis, sieches, and flooding. The site does not lie near any large bodies of water, so the threat of tsunami, sieches, or other seismically -induced flooding is unlikely. The site is located within Other Flood Areas, Zone X (as shown on Plate A-8). The areas of 1% annual chance flood with average depth of less than 1 foot or with drainage area less than 1 square mile. ► Expansive soil. The near surface soils at the project site consist of silty sands/sands which are non -expansive. Site Preparation Clearing and Grubbing Any surface improvements, debris or vegetation including grass, brush, and weeds, on the site at the time of construction should be removed from the construction area. Root balls should be completely excavated. Organic stripping should be hauled from the site and not used as fill. Any trash, construction debris, and buried obstructions such as sprinkler and leach lines exposed during rough grading should be traced to the limits of the foreign material by the grading contractor and removed under our supervision. Any excavations resulting from site clearing should be dish -shaped to the lowest depth of disturbance and backfilled under the observation of the geotechnical engineer's representative. LandMark Consultants, Inc. Page 6 APN 773-360-013 — La Quinta, CA LCI Report No. LP18112 Building Pad Preparation: The existing surface soil within the proposed building pad should be removed to 18 inches below the lowest foundation grade or 36 inches below the original grade (whichever is deeper), extending five feet beyond all exterior wall/column lines (including adjacent concrete areas). Exposed sub -grade should be scarified to a depth of 8 inches, uniformly moisture conditioned to at least 2% over optimum moisture content and re -compacted a minimum of 90% of the maximum density determined in accordance with ASTM D 15 57 methods. The native granular soil is suitable for use as compacted fill and utility trench backfill. The native soil should be placed in maximum 8 inches lifts (loose), uniformly moisture conditioned to at least 2% of optimum moisture content, and re -compacted to a minimmm of 90% of the maximum density determined in accordance with ASTM D1557 methods. Imported fill soil (if needed) should similar to onsite soil or non -expansive, granular soil meeting the USCS classifications of SM, SP-SM, or SW-SM with a maximum rock size of 3 inches. The geotechnical engineer should approve imported fill soil sources before hauling material to the site. Imported granular fill should be placed in lifts no greater than 8 inches in loose thickness, uniformly moisture conditioned to at least 2% over optimum moisture content, and re -compacted to a minimum of 90% of the maximum density determined in accordance with ASTM D1557 methods. In areas other than the house pad which are to receive concrete slabs and pavements, the ground surface should be over -excavated to a depth of 18 inches, uniformly moisture conditioned to at least 2% over optimum moisture content, and re -compacted to a minimum of 90% of the maximum density determined in accordance with ASTM D 15 57 methods Soil Bearing Values and Lateral Loads The subsurface soils consist of sand with some gravel to maximum penetrated. An allowable soil bearing pressure of 1,800 psf could be used. Passive resistance of lateral earth pressure may be calculated using an equivalent fluid pressure of 350 pcf to resist lateral loadings. The top one foot of embedment should not be considered in computing passive resistance unless the adjacent area is confined by a slab or pavement. An allowable friction coefficient of 0.4 may also be used at the base of the footings to resist lateral loading. Static earth pressure equivalent to that exerted by a fluid weighing 35 pcf for unrestrained (active) conditions and 50 pcf for restrained (at -rest) conditions. LandMark Consultants, Inc. Page 7 APN 773-360-013 — La Quinta, CA LCI Report No. LP18112 Foundation All exterior and interior foundations should be embedded a minimum of 12 inches deep. Continuous wall footings should have a minimum width of 12 inches. Spread footings should have a minimum width of 24 inches and should not be structurally isolated. Recommended concrete reinforcement and sizing for all footings should be provided by the structural engineer. Slabs -on -Grade Concrete slabs and flatwork should be a minimum of 4 inches thick. The concrete floor slabs may either be monolithically placed with the foundation or dowelled after footing placement. The concrete slabs may be placed on granular subgrade that has been compacted at least 90% relative compaction (ASTM D1557). Slab thickness and steel reinforcement should be determined by the design engineer. American Concrete Institute (ACI) guidelines (ACI 302.IR-04 Chapter 3, Section 3.2.3) provide recommendations regarding the use of moisture barriers beneath concrete slabs. The concrete floor slabs should be underlain by a 10-mil polyethylene vapor retarder that works as a capillary break to reduce moisture migration into the slab section. All laps and seams should be overlapped 6-inches or as recommended by the manufacturer. The vapor retarder should be protected from puncture. The joints and penetrations should be sealed with the manufacturer's recommended adhesive, pressure -sensitive tape, or both. The vapor retarder should extend a minimum of 12 inches into the footing excavations. The vapor retarder should be covered by 4 inches of clean sand (Sand Equivalent SE>30) unless placed on 2.5 feet of granular fill, in which case, the vapor retarder may lie directly on the granular fill with 2 inches of clean sand cover. Placing sand over the vapor retarder may increase moisture transmission through the slab, because it provides a reservoir for bleed water from the concrete to collect. The sand placed over the vapor retarder may also move and mound prior to concrete placement, resulting in an irregular slab thickness. For areas with moisture sensitive flooring materials, ACI recommends that concrete slabs be placed without a sand cover directly over the vapor retarder, provided that the concrete mix uses a low-water cement ratio and concrete curing methods are employed to compensate for release of bleed water through the top of the slab. The vapor retarder should have a minimum thickness of 15-mil (Stego-Wrap or equivalent). LandMark Consultants, Inc. Page 8 APN 773-360-013 — La Quinta, CA LCI Report No. LP18112 Control joints should be provided in all concrete slabs -on -grade at a maximum spacing (in feet) of 2 to 3 times the slab thickness (in inches) as recommended by American Concrete Institute (ACI) guidelines. All joints should form approximately square patterns to reduce randomly oriented contraction cracks. Contraction joints in the slabs should be tooled at the time of the pour or sawcut (114 of slab depth) within 6 to 8 hours of concrete placement. Construction (cold) joints in foundations and area flatwork should either be thickened butt joints with dowels or a thickened keyed joint designed to resist vertical deflection at the joint. All joints in flatwork should be sealed to prevent moisture, vermin, or foreign material intrusion. Precautions should be taken to prevent curling of slabs in this and desert region (refer to ACI guidelines). All independent concrete flatworks should be underlain by 12 inches of moisture conditioned and compacted soils. All flatwork should be jointed in square patterns and at irregularities in shape at a maximum spacing of 10 feet or the least width of the sidewalk. Concrete Mixes and Corrosivity Selected chemical analyses for corrosivity were conducted on bulk samples of the near surface soil from the project site (Plate C-2). The native soils have low levels of sulfate and chloride ion concentrations. Resistivity determinations on the soil indicate a severe potential for metal loss because of electrochemical corrosion processes. A minimum of 2,500 psi concrete of Type II Portland Cement with a maximum water/cement ratio of 0.60 (by weight) should be used for concrete placed in contact with native soil on this project (sitework including streets, sidewalks, driveways, patios, and other wall foundations). Landmark does not practice corrosion engineering. We recommend that a qualified corrosion engineer evaluate the corrosion potential on metal construction materials and concrete at the site. Observation and Density Testing Site preparation and fill placement should be continuously observed and tested by a representative of a qualified geotechnical engineering firm. Near full-time observation services during the excavation and scarification process is necessary to detect undesirable materials or conditions and soft areas that may be encountered in the construction area. The geotechnical firm that provides observation and testing during construction shall assume the responsibility of "geotechnical engineer of record" and, as such, shall perform additional tests and investigation as necessary to satisfy themselves as to the site conditions and the recommendations for site development. LandMark Consultants, Inc. Page 9 APN 773-360-013 — La Quinta, CA LCI Report No. LP 18112 We did not encounter soil conditions that would preclude implementation of the proposed project provided the recommendations contained in this report are implemented in the design and construction of this project. We appreciate the opportunity to provide our findings and professional opinions regarding geotechnical conditions at the site. If you have any questions or comments regarding our findings, please call our office at (760) 360-0665. Respectfully Submitted, LandMark Consultants, Inc. P.E., M.ASCE Q ioF ESSib lu No, C 34432 TAT CIVIL OF [:AI Attachments: Appendix A: Vicinity and Site Maps Appendix B: Subsurface Soil Logs and Soil Key Appendix C: Laboratory Test Results Appendix D: References LandMark Consultants, Inc. Page 10 77137 Casa del Sol -- La Quinta, CA LCI Project No. LP18112 Table 1 Summary of Characteristics of Closest Known Active Faults Fault Name Approximate Distance (miles) ApproximateFault Distance (km) 7M�a�gnitude Length (km) Slip Rate (mm/yr) San Andreas - San Bernardino (South) 8.7 13.9 7.4 103 110 30 f 7 San Andreas - Coachella 8.7 13.9 7.2 96 f 10 2515 San Andreas - San Bernardino (North) 8.8 14.0 7.5 103 f 10 24 f 6 Indio Hills * 10.1 16.1 Garnet Hill * 14.2 22.8 Blue Cut * 16.7 26.7 San Jacinto - Anza 17.0 27.1 7.2 91 9 12 f 6 San Jacinto - Coyote Creek 18.9 30.2 6.8 41 4 4 f 2 Eureka Peak 19.8 31.7 6.4 19 f 2 0.6 f 0.4 Burnt Mtn. 27.1 43.3 6.5 21 f 2 0.6 f 0.4 Morongo * 29.5 47.2 Pinto Mtn. 31.2 49.9 7.2 74 f 7 2.5 f 2 Hot Springs * 33.4 53.5 San Jacinto - Borrego 33.5 53.6 6.6 F29± 4 ± 2 Landers 34.4 55.1 7.3 83 f 8 0.6 f 0.4 Pisgah Mtn. -Mesquite Lake 35.5 56.8 7.3 89 f 9 0.6 f 0.4 San Jacinto - San Jacinto Valley 36.6 58.5 6.9 43 f 4 12 f 6 Earthquake Valley 37.3 59.8 6.5 20 f 2 211 Elsinore - Julian 39.9 63.8 7.1 76 t 8 5 f 2 S. Emerson - Copper Mtn. 42.9 68.6 7 54 f 5 0.6 f 0.4 Johnson Valley (northern) 43.8 70.1 6.7 35 f 4 0.6 f 0.4 Elsinore - Temecula 44.2 70.8 6.8 43 f 4 5 f 2 * Note: Faults not included in CGS database. 77137 Casa del Sol -- La Quinta, CA LCI Project No. LP18112 Table 2 2016 California Building Code (CBC) and ASCE 7-10 Seismic Parameters CBC Reference Soil Site Class: D Table 20.3-1 Latitude: 33.6733 N Longitude:-116.3186 W Risk Category: II Seismic Design Category: D Maximum Considered Earthquake (MCE) Ground Motion Mapped MCER Short Period Spectral Response S. 1.500 g Figure 1613.3.1(1) Mapped NICER 1 second Spectral Response SI 0.601 g Figure 1613.3.1(2) Short Period (0.2 s) Site Coefficient Fa 1.00 Table 1613.3.3(1) Long Period (1.0 s) Site Coefficient Fv 1.50 Table 1613.3.3(2) MCER Spectral Response Acceleration Parameter (0.2 s) SMs 1.500 g = F, * S, Equation 16-37 MCER Spectral Response Acceleration Parameter (1.0 s) SAIL 0.902 g = F, * SI Equation 16-38 Design Earthquake Ground Motion Design Spectral Response Acceleration Parameter (02 s) SDs 1.000 g = 2/3*SMs Equation 16-39 Design Spectral Response Acceleration Parameter (1.0 s) SDI 0.601 g = 2/3*SMI Equation 1640 Risk Coefficient at Short Periods (less than 0.2 s) CRs 1.066 ASCE Figure 22-17 Risk Coefficient at Long Periods (greater than 1.0 s) CRI 1,029 ASCE Figure 22-18 TL 8.00 sec ASCE Figure 22-12 To 0.12 sec =0.2*SDI/SDs Ts 0.60 sec =SDI/SDs Peak Ground Acceleration PGAM 0.52 g ASCE Equation 11.8-1 ' wii i !!m; raid'��■i����lC....1,i...lilawww.C.ww.wwiir■r■= 0.6 0.7 1:1 1 1.21 1 1.ii!!!!lww�wlwC.�lwwliwliiiii 41 11 1 41 •1 2.8 3.00 1 4.00 11 0.80 1 0.55 0.50 0.50 0.43 0.40 1 1 1 1 1 1 0.21 0.20 0.17 0.15 1.50 1.20 0.82 0.75 0.75 0.64 0.60 1 .12 0.45 0.41 0.38 0.35 1 .32 0.30 0.26 1 1^OINUM-C�liltrCrrrrr�r 1mew I I!OR w!!!!!!!liOZZZEtiiilii!!!!!!!! 1 !lw!! _ !!!!!!ii!'f i! il•1)E! ! w !!!!!! �!!!! !!!!. iwwwwww... i!!!!!i!!i\i! !►'ii!!!i!!!! i!!!!!!!! llwwwNwlwwlM.ariwlNww�.;_•�Irrwwr�w�wiw iwwlwwww! ii!!!!!!liliiiliii� i�!liiiii!!!!!!! !!!!!!i!!iwliltwilii�.,- itlilwi!!!!!!i1.51 1 !!!lliwwilii!li�r!!liww���1fl�wwilii :I�_ 1 iiiiiwiliili!!ii !!l"iwm iliiw!!!!!!!!!i i!!1.1l0 =owwwwi iiiiCwiilwwwwii iiil•iw 1 1 !!>•!!�! iiiiiii iiii !iliiilii! !!!!!!• 11 1 1 1 1 1 .■ .- �- . •• •- Lancaster t _•� +1 almdale ��. 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IVJEC-1 - Source: California Geological Survey 2010 Fault Activity Map of California http://www.quake.ca.gov/gmaps/FAM/faultactivitymap.htm1# LANDMARK Project No.: LP18112 Regional Fault Map Figure 1 ` a� l -"3.a: _ _ aloe.. �• 17 .` ��.', Joshua Tree Palfre- 't:r Lu�rti�,xsxNaZi�ynal Park �1 �{ Thnusan�. �� �$ rings r ,,l r `; ,• - V Pal-r5 ''- grare`Parsi . thLdral dy I�yl�wrld•Prne �+.• � t __ 6ermud�`f ' Co�•, ver G �,•y Cunes ^Palm Desert Indiya' loanella # } z +, ��❑ 7herma'jj ;—� # 77' . ♦�Rftz- G� •:. � � '. _ �.+i'- _ � fig �' r��-- -.r Source: California Geological Survey 2010 Fault Activity Map of California http:i/www.quake.ca.gov/gmaps/FAM/faultactivitymap.html# LANUMARK 9 --- Project Site VA JR -. Ot r=i?c Ff• •�4 I� Project No.: LP18112 1I Map of Local Faults 11 Figure 2 11 EXPLANATION Fault traces on lend are indicated by solid lines where well located, by dashed lines where approximately located or Inferred, and by dolled lines where concealed byymngwrmks a by lakes or bays Foultmices are quarted where continuation or existence is uncertain Concealed faults in the Great Valley are based on maps of selected subsurface horizons, so locations shown are approximate and may Indicate structural brand only Al ogshore faults based on seismic reflection profile records are shown as solid lines where well defined, dashed where Inferred, queued whore uncertain. FAULT CLASSIFICATION COLOR CODE (Indicating Recency of Movement) ' Fault along which historic (lest 200 years) displacement has occurred and is associated with one or more of the following: (a) a recorded earthquake with surface mplure (Also Included ere some well-defined surface breaks used by ground shaking during earth Wakes, e g extensive ground breakage, not on the White Wok fault, caused by the AMr,Tehachepl earthquake of 1952) The dale of the associated earthquake is indicated Where repeated surface ruptures on the same fault have occurred, only the date of the latest movement may be indicated, especially hearller reports are not well documented as to location of ground breaks (b) fault creep slippage - slow ground displacement usually without accompanying earthquakes (c) displaced survey tins A triangle to the right or left of the dale indicates termination point of observed surface displacement Solid red Idengle indicates known location ofrupture lamination point Open blecklrlangle indicates uncertain or estimated location of mplure lamination point e iri Date bracketed by triangles indicates local fault break No triangle by dale indicates an Intermediate point along fault break Fswll Met tcn,dla Muff creep slippage Hachures Indicate linear extent of fault creep Annotation (creep asar� with la ader) Inacaloe nopmevnl ffwa Iocellare whore fault creep has been observed and recorded S¢ram m Iowa killcalm where lewd creep alppsgo hoe occwed that has been triggered by an earthquake onsomedherfaull Dsledesuseu6w eaMplekeln /CIHae SWarestoright and left ofdate indicate luM- f" net prints helwean which triggered creep Mlyp+pe has occurred (creep either continuous a inlinmitienl hetwem these end points) Holocene Paull dlspiri. nl (during past 11,700 years) without historic record Geomorphic evidence for Holocene faulting includes sag ponds, scarps showing little erosion, or the following features In Holocene age deposits: offset stream courses, linear scarps, shutter ridges, and triangular faceted spurs. Recency of faulting offshore is based on the interpreted age of vie youngest strata displaced by faulting Let. Ouelernary fault displacement (during pest 700,000 years). Geomorphic evidence similar to that described for Holocene %oils except features are less distinct Faulting may be younger, but lack of younger overlying deposits precludes more accurate age classification -- .....s. Quaternary fault (age undifferentiated) Most faults oflhis category show evidence of displacement some- time during the pest 1 6 mllllm years; possible exceptions are faults which displace rocks of undifferenfi- .led Pao-Plelstocene age Unnumbered Quaternary faults were based on Faulk Map of California, 1975 See Bulletin 201, Appendix D for source data .�. �. ..�- Pre-Quelemary fault (older that 16 million years) or Mull without recognized Qualemary displacement Samefautis ere shown in (his category De use the source or mapping used was draConnalgance na", a was net done with the O%ed of doling fault displacements Faults in this category are not necessonly ineclive. ADDITIONAL FAULT SYMBOLS _—t_._- _. ._....... Bar and ball on dawnthrown side (relative or apparent) W____,,, . a Arrows along fault indicate relalive or apparent direction of lateral movement Arrow on fault indicates direction ofdlp- --T—. x Low angle Mult(barbs on upper plate) Fault surface generally dips Ins [ban 45° butlocellymayhavebeen subsequently steepened On offshore faults, barbs simply Indicate a reverse fault regardless of steepness of dip OTHER SYM13OLS Nu lbers refer 10 i mndeli&m fle3e l in the eppendcas of th a scoompmynp report Aneolattebk include faun Rep C ego of Ilult leeeeeefk, and pedlneal references ncWnp BeAhgllklu Fault Zprs maps whom it fault has been zoned by the P/qulst• Pride Earthquake Fault ZmingAct This AA regW m the BINe Oec4o• glsl to delineate zones to encompass faults wllh Holocene displacement -., .,-. _...�. Structural discontinuity (offshore) separating differing Neogene structural domains May Indicate dlscoalk rxwWtlg bGtwe" Iurf nt wka &ewley Selsmic Zone, a liner zone of seismicity locally up to 10 km wide associated with the releasing Cap between me Imperial end San ArXm 9 faults. Years DESCRIPTION Geologic Before Fault Rccency Time Present Symbol of Scale (Approx.) Movement ON LAND OFFSHORE e Dlspleremenl d—g halorrc llme(e.g —Am—, hu111906) kKT � Ircluaea ereaa aNnovn, reun cup a � ^hmr!ng en M1 sr:l nu:ino, Fewil Fit: shalt. of �e'e P�su-I�cS�e ayr- � q,j 4 4 lr � 7P0,9gg rru:l art: y" G P p or 1,&M,090' T FwAa wshofn f.toplo-ea nee. a.raarre mYpe.r. rr Oualemery dplecamea or ahevxrlg ri ol peer rga eh,,niduQ ry the Not.tterayinadW d w 4 50aa0e 'Oumemery now recopfaeeuexlemEip lo36Me (Weller ant Gehamen 2009) ouehmery reu6a lnfhk mp vrore eelebeshetl mkg vie preNwa 1 6 Me crllMm "- •-Y- �, • - � .! � �ti ill. 1 T ,t .r.l+�+( 1 H r11� f Y l r NATIONAL to t' b i,a 1 frZ :+ fr{r*Y fi�gp MONUMENT � mow• � z .. ' - A '� t � -� ��0. tj R YZ7 F T A i Vy{Y�{1 F' "lII/Giil•1G1 ►AIP /�A'J t q'' AM INGS RAN IM0 awl ., ia� n r,-.,� ;(n ! rat �•� ; j• WRAGI Cirf a1iw I � r+Aiii�arA� .'t. 19 • � ti � � �{ UnA 0 u r• r Esc-• '„r• •'�r.�o�`�. � I 4. � i ■ fit � • ur. �. rty—�V�•,�r�, - _ ~ n Y1.wil�i .�i• � ''�, INO 'LC>r� �1YSry4}e•tli! `.�Js '��-�_ _'� 1.•..,...r'Mfi 1 !-� � �-. •� r. f% � M�• �r �_�VVI{ �1 HN w _ •. r YYKAljl10 nas �, •_ {,-•• '';•• • 1i i �{I 9` FA 5471p1y1f SY s � n'ri✓!'».»�I .. i-,�rt.,� ly' ,. .. 1 r �1 '.� }y ir�M �� � u-i. ` 6 •I ,✓r. _"I � � n.....T . Fes. L + EQRESI '� - / � IIOti{ . _ "' .; � � " ". nuln_,.uc: . :c �+•C�,.��� 4.� f �i � �� .. Is �y 7 r wlrlAtl .v q lC r 1' 1q � �+tswwnW4� s.e-.�n •• srorwbev�' . . � • 1 sAreut ; � � ..i . s � t tvltni'u't 6 lll r... .SNne•1 wRl-M.nNN• � w�77. :•1�[•-. 9 Project Site J LANDMARK .,, Plate Project No.: LP18112 Vicinity Map A-1 • _ r r 44 * T-1 T 2 -�Ok ` SM t i Legend �f Approximate Test Pit Location LANUMARK Plate Project No.: I_P18112 Site and Exploration Plan A-2 �L s � r - 01r, Project Site 1 *� s "• •. IL xx a '+ • u � r r Naiatcnl Rnsaaauces �4t.:vd :u^rey f,unS[:iVi➢t1n11 '4 P.iVi4;i` li?10.1r. i1f •[��Il.fa�lllw?`�7i![I :uiy.- . LANUMARK USDA Soil Conservation Plate Project No.: LP18112 Soil Service Map A-3 Soil Map —Riverside County, Coachella Valley Area, California Map Unit Legend Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI CdC Carsitas gravelly sand, 0 to 9 percent slopes 3.5 56.0% RU Rubble land 2.8 44.0% Totals for Area of Interest 6.3 100.0% USDA Natural Resources Web Soil Survey 7/19/2018 vNION Conservation Service National Cooperative Soil Survey Page 3 of 3 Project Site • - �i. � ire: f�ZA'�Cf..i i i� lli T�nilrodx (q r1 [ + 1 Qelnrm� 4'u�iah 51f' Rt�lo6 tiutnr-e i7wi IJtiJ;S 'M It knY'. 1 : ;.f,o Nl , 11, 1 1 ull= 14'Uw LANUMARK Plate Project No.: LP18112 Topographic Map A-4 I Flores V Fwit Mlp f�Y fir' � -^• ,.r �I i�.� '.:• :• _ :i."� V. 'ter f •_'� t. ;. w y r. i'iL J �+ ' �} • 77 •n -_ r it !.- Project Site f '� •IMP 'llit:":I Ii1RR1 and❑MP mQ In M r:wi fx Mro I nr:: v ni Kf u:r •, nr f V•n rr'.,rTQ,"T \ aral r'r •v• i—,,%. �'•p 4,4444 rW -❑ �....,ry ••rrr-�H47 i, . ��•xnJ' '+ u ...u.•.r gig ... •4,. i+• h9 r; m p�rran•ra es Io§10 :anuru �U•u :dno ti n4l.)1"•4 pe't,� r:cu�c4-fe,ru• wsn: d .u1-1rg rd fir dlrf.. r.•r.,•$-! n •r'.+K�l .-1e rr l',ir•'.P•rlh r1 IfA-1V-�. r+Prf r''�r' • I -Q%-oklm +:4 y'::'.41v, l+:r 00Plf'N SL'f'�.plr141L'. R, 4r _ �� Rc•'; r7 p OW.V'❑ i.r+:. W1 rK,al: 12.' A W rr.Wsru ('41Arl IWAt 015 LANDMARK Riverside County r r Geographic Information System (GIS) Plate Project No.: LP18112 Fault Map A-5 Project Site 0 I Notes FCi7 1 LANDMARK Riverside County Geographic Information System (GIS) Plate Project No.: LP18112 Subsidence A-6 M Naves Liquefaction Map Project Site IMPORTM1T 'da*", intl0; aura to ne ov5fnr;ript�-n a e lempa5011 nnr� K<Ar, Staler at 4Orr %:n•atA R�I�, enJmt, otne:ossxa�j,iccsrrto t<r i�r�eytn 6}er �ig�.nerennrlstargiros?!re :..vulah��'Rwe�,uc�❑�xKrs din os�tT ;.r yasa J!.e n; 'a !'ie :. �srenn[ {tl,e , rs-; i�, nllen'L �I rra;fil, 1""r,a<-/ Iv�elmr�ss r„ -:rmyrleto -3 a-Y of lh9 data Pro, ,tk!f_ avi a t c.: naps �a+sge' Ie.panL cdR; ser the an fonva�Q tnnrer•rl vS01,, mr-1, Pny p-e tlrrV? l nsaen!;n,It inn tnP ^ihy nl 5.�,';, r HFI Inn """, REr'� IRI F'C{IN DUN Bll1, H29DHAM - Rrve ,•Je+Irtntv'3.I f Gl'S LANDMARK Riverside County Geographic Information System (GIS) Plate Project No.: LP18112 Liquefaction Zones q_7 I. iFlood Map Tijuana Notes I I egend Project Site I i LANUMA11K Riverside County Geographic Information System (GIS) Plate Project No.: LP18112 Flood Map A-8 LEGEND SPECIAL FLOOD HAZARD AREAS SUBJECT TO INUNDATION BY THE 1% ANNUAL CHANCE FLOOD The 1% annual flood (100-year flood), also known as the base flood, is the flood that has a 1% chance of being equaled or exceeded in any grven year, The Specal Flood Hazard Area is the area subject to flooding by the 1% annual chance flood. Areas of Special Flood Hazard Include Zones A, AE, Ali, AO, AR, A99, V, and VE. The Base Flood Elevation is the water -surface elevation of the 1% annual chance flood. ZONE A No Base Flood Elevations determined. ZONE AE Base Flood Elevations determined. ZONE AH Flood depths of 1 to 3 feet (usually areas of ponding); Base Flood Elevations determined. ZONE AO Flood depths of I to 3 feet (usually sheet flow on sloping terrain); average depths determined. For areas of alluvial fan flooding, velocities also determined. ZONE AR Special Flood Hazard Area formerly protected from the 1% annual chance flood by a flood control system that was subsequently decertified. Zone AR indicates that the former flood control system is being restored to provide protection from the 1% annual chance or greater flood, ZONE A99 Area to be protected from L% annual chance flood by a Federal flood protection system under construction; no Base Flood Elevations determined. ZONE V Coastal flood zone with velocity hazard (wave action); no Base Flood Elevations determined. ZONE VE Coastal flood zone with velocity hazard (wave action); Base Flood Elevations determined. FLOODWAV AREAS IN ZONE AE The floodway Is the channel of a stream plus any adjacent floodplain areas that must be, kept free of encroachment so Lhal the 1% annual chance flood can be carried without substantial increases in flood heights. OTHER FLOOD AREAS ZONE X Arms of 0.2% annual chance flood; areas of 1% annual chance flood with average depths of less than 1 foot or with drainage areas less than 1 square mile; and areas protected by levees from 1% annual chance flood. OTHER AREAS ZONE X Areas determined to be outside the 0.2% annual chance l"plain. ZONE D Areas in which flood hazards are undetermined, but possible. ® COASTAL BARRIER RESOURCES SYSTEM (CBRS) AREAS OTHERWISE PROTECTED AREAS (OPAs) CBRS areas and OPAs are normally located within or adjacent to Special Flood Hazard Areas. 1% annual chance noodfain boundary 0.2% annual chance foodplam boundary Flrlodway boundary Zone D boundary ................ CBRS and OPA boundary -«� Boundary dividing Special Flood Hazard Area Zones and +— boundary dividing Special Flood Hazard Areas of different Base Flood Elevations, flood depths or flood velocities. Base Flood Elevation line and value; elevation In feet' (EL 987) Base Flood Elevation value where uniform within zone; elevation in feet' • Referenced to the North American vertical Datum of 1988 Cross section line p1 _ _ — _ _ za Transect line 87'07'45", 32°22'30" Geographic coordinates referenced to the North American Datum of 1983 (NAD 83), Western Hemisphere 76" N 1000-meter Universal Transverse Mercator grid values, zone 11N 600000 FT 5000-foot gntl ticks: California State Plane coordinate system, zone V1 (FIPSZ(NJE 0406), Lambert Conformal conic projection DX5510 X Bench mark (see explanabon in Notes to Users section of this FIRM panel) M 1.5 River Mlle = W FIELD LOG OF TEST PIT NO. T 1 SHEET 1 OF 1 DESCRIPTION OF MATERIAL LABORATORY J a < Mtn H �� m o w Uz O a rn o o n 5 Z co o OTHER TESTS 5 10 15 20 25 30 SAND (SP-SM): Brown, dry, loose, medium grained, medium dense, some cobbles and boulders to 1 to 3 ft. 132.1 116.8 2.1 2.8 Passing #200 = 9.5% Total Depth = 14.5' Moisture and density values by Nuclear Densometer (ASTM 6938) Backfilled with excavated soil DATE EXCAVATED: 6/22/18 TOTAL DEPTH: 14.5 Feet DEPTH TO WATER: N/A LOGGED BY: J. Lorenzana TYPE OF BIT: Backhoe DIAMETER: N/A SURFACE ELEVATION: HAMMER WT.: N/A DROP: N/A PROJECT NO. LP18112 LANAAu PLATE B-1 = wJ FIELD LOG OF TEST PIT NO. T-2 SHEET 1 OF 1 LABORATORY Q W tri o �V I- of o mU w ow as o o a j Z 0 o-- OTHER TESTS DESCRIPTION OF MATERIAL - 5 10 15 20 25 30 — SAND (SP-SM): Brown, dry, loose, medium grained, medium dense, some cobbles and boulders to 1 to 3 ft. 122.1 113.6 2.0 2.5 Total Depth = 14.5' Moisture and density values by Nuclear Densometer (ASTM 6938) Backfilled with excavated soil DATE EXCAVATED: 6/22/18 TOTAL DEPTH: 14.5 Feet DEPTH TO WATER: NIA LOGGED BY: J. Lorenzana TYPE OF BIT: Backhoe DIAMETER: N/A SURFACE ELEVATION: HAMMER WT.: N/A DROP: N/A PROJECT NO. LP 18112 LANUMARK PLATE B-2 DEFINITION OF TERMS PRIMARY DIVISIONS SYMBOLS SECONDARY DIVISIONS Gravels GW Well graded gravels, gravel -sand mixtures, little or no fines Gaon gravels pass �`>;'� than 5%fines) • • A GP Poorly graded gravels, or gravakand mixtures, little or no fines More than half of 1! GM Silty gravels, gravel -sand -sin mixtures, non -plastic fines coarse fr o larger thann No. 4 sieve Gravel with fines Gc - Gayey gravels, grave4sand-clay mixtures, plastic fines Coarse grained soils More han half of material is large that No. 200 sieve Sands $W Well graded sands, gravelly sands, little or no fines Clean sands (less - than 5%fines) $P Poorly graded sands or gravelly sands, little or no fines More than half of _ �';•; SM Silty sands, sand -sill mixtures, non -plastic fines coarse fraction is smaller than No.4 wave Sands with fines r SC Clayey sends, sand -clay mixtures, plastic fines Silts and clays II Ill ll ML Inorganic sins, clayey sins with slight plasticity CL Inorganic clays of low to medium plasticity, gravely, sandy, or lean clays Liquid limn is less than 50% " ' "' ' 1. 1 �I it OL Organic sins and organic clays of low plasticity (Fine grained soils More that half of material is smaller Silts and clays j 1111 MH Inorganic sins, micaceous or diatomaceous silty soils, elastic sins than No. 200 sieve CH Inorganic clays of high plasticity, fat clays Liquid limit is more than 50 % �� OH Organic clays of medium to high plasticity, organic sins l Highly organic soils ri1 PT Peat and other highly organic soils GRAIN SIZES Sand Gravel Silts and Clays Cobbles Boulders Fine Medium Coarse Fine Coarse 2..00 40 10 4 314" 3" 12 US Standard Series Sieve Sands, Gravels, rlc, Blowsift. Very Loose 0-4 Loose 4-10 Medium Dense 10-30 Dense 3050 Very Dense Over 50 Clear Square Openings Gays 8 Plastic Sifts Strength *' Blows/ft. Very Soft M.25 0-2 Soft 0.25-0.5 2-4 Firm 0.5-1.0 4-8 Stiff 1.0-2.0 6-16 Very Stiff 2.04.0 16-32 Herd Over 4.0 Over 32 * Number of blows of 140 lb. hammer falling 30 inches to drive a 2 inch O.D. (1 3/8 in. I.D.) split spoon (ASTM D1586). ** Unconfined compressive strength in tons/s.f. as determined by laboratory testing or approximated by the Standard Penetration Test (ASTM D1586), Pocket Penetrometer, Torvane, or visual observation. Type of Samples: 11 Ring Sample Ej Standard Penetration Test I Shelby Tube ® Bulk (Bag) Sample Drilling Notes: 1. Sampling and Blow Counts Ring Sampler - Number of blows per foot of a 140 lb. hammer falling 30 inches. Standard Penetration Test - Number of blows per foot. Shelby Tube - Three (3) inch nominal diameter tube hydraulically pushed. 2. P. P. = Pocket Penetrometer (tons/s.f.). 3. NR = No recovery. 4. GWT ? = Ground Water Table observed @ specified time. LANDMARK Cieo-Engineem and Geologists I Plate Project No. LP18112 Key to Logs B-3 SIEVE ANALYSIS Cobbles and Boulders Gravel I Sand Sift and Clay Coarse I Fine I Coarse Medium I Fine so 60 r+ t 70 271, A 60 C 'w a m IL w d L d a 40 Particle Size (mm) LANDMARK Plate Project No,: LP18112 Grain Size Analysis C4 LANDMARK CONSULTANTS, INC. CLIENT: Coronel Enterprises, Inc. PROJECT: 77137 Casa del Sol -- La Quinta, CA JOB No.: LP18112 DATE: 07/02/18 ------------------------------------------------------------------------------------------------------------------------------------------------------- --------------------------------------------------------- CHEMICAL ANALYSIS Boring: T-1 Caltrans Sample Depth, ft: 0-3 Method pH: 8.5 643 Electrical Conductivity (mmhos): -- 424 Resistivity (ohm -cm): 1,600 643 Chloride (CI), ppm: 110 422 Sulfate (SO4), ppm: 53 417 General Guidelines for Soil Corrosivi Material Chemical Amount in Degree of Affected Agent Soil (ppm) Corrosivity Concrete Soluble 0-1,000 Low Sulfates 1,000 - 2,000 Moderate 2,000 - 20,000 Severe > 20,000 Very Severe Normal Soluble 0 - 200 Low Grade Chlorides 200 - 700 Moderate Steel 700- 1,500 Severe > 1,500 Very Severe Normal Resistivity 1 -1,000 Very Severe Grade 1,000 - 2,000 Severe Steel 2,000 - 10,000 Moderate > 10,000 Low I Nl'.. I mLjl n.. Min., Project No.: LP18112 Selected Chemical Test Results Plate C-2 Client: Coronel Enterprises, Inc. Project: 77137 Casa Del Sol -- La Quinta, CA Project No.: LP18112 Date: 7/2/2018 Lab. No.: N/A 140 130 110 100 Soil Description: Sand (SP-SM) Sample Location: T-1 @ 0-3 ft. Test Method: ASTM D-1157 A Maximum Dry Density (pcf): 134.9 Optimum Moisture Content (%): 6.5 0 5 10 15 Moisture Content (%) 20 —Curves of 100% saturation for specific gravity equal to: 2.75 7 2.70 2.65 25 30 LANUMARK Plate Moisture Density Relationship C-3 Project No_: LP18112 REFERENCES American Concrete Institute (ACI), 2013, ACI Manual of Concrete Practice 302.1R-04 American Society of Civil Engineers (ASCE), 2010, Minimum Design Loads for Buildings and Other Structures: ASCE Standard 7-10. California Building Standards Commission, 2017, 2016 California Building Code. California Code of Regulations, Title 24, Part 2, Vol. 2 of 2. Caltrans, 2012, Highway Design Manual. California Division of Mines and Geology (CDMG), 1996, California Fault Parameters: available at http://www.consrv.ca.goy/ding/slieM/fltindex.htinl. California Geological Survey (CGS), 2008, Guidelines for Evaluating and Mitigating Seismic Hazards in California, Special Publication 117A, 98p. California Geological Survey (CGS), 2018, Fault Activity Map of California h ttp : llwww.quake. ca. govlf-,inaps[F'A Mlt aul tac U yi tvnl ap . h tm ] 4 . California Geological Survey (CGS), 2018, Alquist-Priolo Earthquake Fault Zone Maps. http:Ilmaps.conseivation.ca.gov/c s/inforiiiatioiiwareliouse/index.litml?inap=regul atorymaps Cetin, K. O., Seed, R. B., Der Kiureghian, A., Tokimatsu, K., Harder, L. F., Jr., Kayen, R. E., and Moss, R. E. S., 2004, Standard penetration test -based probabilistic and deterministic assessment of seismic soil liquefaction potential: ASCE JGGE, Vol., 130, No. 12, p. 1314-1340. Geologismiki, 2017, CLiq Computer Program, www.geologismiki.gr Ishihara, K. (1985), Stability of natural deposits during earthquakes, Proc. II"' Int. Conf. On Soil Mech. And Found. Engrg., Vol. 1, A. A. Balkema, Rotterdam, The Netherlands, 321-376. Jones, A. L., 2003, An Analytical Model and Application for Groturd Surface Effects from Liquefaction, PhD. Dissertation, University of Washington, 362 p. McCrink, T. P., Pridmore, C. L., Tinsley, J. C., Sickler, R. R., Brandenberg, S. J., and Stewart, J. P., 2011, Liquefaction and Other Ground Failures in Imperial County, California, from the April 4, 2010, El Mayor—Cucapah Earthquake, CGS Special Report 220, USGS Open File Report 2011-1071, 84 p. Post -Tensioning Institute (PTI), 2007a, Standard Requirements for Analysis of Shallow Concrete Foundations on Expansive Soils (3rd Edition). Post -Tensioning Institute (PTI), 2007b, Standard Requirements for Design of Shallow Post -Tensioned Concrete Foundations on Expansive Soils (2" d Edition). Robertson, P. K., 2014, Seismic liquefaction CPT -based methods: EERI 15t Workshop on Geotechnical Earthquake Engineering — Liquefaction Evaluation, Mapping, Simulation and Mitigation. UC San Diego Campus, 10/12/2014. Robertson, P. K. and Wride, C. E., 1997, Cyclic Liquefaction and its Evaluation based on the SPT and CPT, Proceeding of the NCEER Workshop on Evaluation of Liquefaction Resistance of Soils, NCEER Technical Report 97-0022, p. 41-88. Rymer, M.J., Treiman, J.A., Kendrick, K.J., Lienkaemper, J.J., Weldon, R.J., Bilham, R., Wei, M., Fielding, E.J., Hernandez, J.L., Olson, B.P.E., Irvine, P.J., Knepprath, N., Sickler, R.R., Tong, .X., and Siem, M.E., 2011, Triggered surface slips in southern California associated with the 2010 El Mayor-Cucapah, Baja California, Mexico, earthquake: U.S. Geological Survey Open -File Report 2010-1333 and California Geological Survey Special Report 221, 62 p., available at http://pubs.usgs.gov/of/ 2010/1333/. U.S. Geological Survey (USGS), 1990, The San Andreas Fault System, California, Professional Paper 1515. U.S. Geological Survey (USGS), 2017, US Seismic Design Maps Web Application, available at http://geohazards.usgs.gov/desiggmgpslus/applica6oti.phn Wire Reinforcement Institute (WRI/CRSI), 2003, Design of Slab -on -Ground Foundations, Tech Facts TF 700-R-03, 23 p. Youd, T. L., 2005, Liquefaction -induced flow, lateral spread, and ground oscillation, GSA Abstracts with Programs, Vol. 37, No. 7, p. 252. Youd, T. L. and Garris, C. T., 1995, Liquefaction induced ground surface disruption: ASCE Geotecimical Journal, Vol. 121, No. 11.