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HomeMy WebLinkAboutLots 19 & 20 Supplemental Geologic Investigation I I I~ ,1 i ,I I , , - ,I I I ~ I 1 ~ ~ j I I I j j I I I , , I I ! I I I ! I I , I I ~ J , < ~ . ,I) \J \ ~ .I1L!.- ... V-~l . SUPPLEMENTAL GEOLOGIC/FAULT INVESTIGATION\, LOTS 19 AND 20, TRACT 9833-3 \ CITY OF TEMECULA, RIVERSIDE COI)NTY, CALIFORNIAI I FOR I I " I ! , I I ! ./ JAMES AND MARDI MARGIOTTA 30655 JEDEDIAH SMITH ROAD TEMECULA, CALIFORNIA 92EM-6 5"'12. w.O. 2963-A-SC -.- - JANUARY 31, 2001 Geotechnical' Geologic' Environmental \ I I. I I I , ,I t I , I a , I I 'I I I -I ~ ,- . Geotechnical' Geologic' Environmental 24890 Jefferson Ave. . Murrieta, California 92562 . (909) 677-9651 . FAX (909) 677-9301 January 31,2001 W.O. 2963-A-SC James and Mardi Margiotta 30655 Jedediah Smith Road Temecula, Califomia 92618 Attention: Mr. James Margiotta Subject: Supplemental Geologic/Fault Investigation, Lots 19 and 20, Tract 9833-3, City of Temecula, Riverside County, California Dear Sir: In accordance with your request and authorization, GeoSoils, Inc. (GSI) is pleased to presentthe results ofthis supplemental geologic fault investigation ofthe subject site. The' site itself is within an Alquist-Priolo Earthquake Fault Zone established by the State of California. This supplemental report specifically addresses onsite faulting and the new digital mapping provided by the County of Riverside concerning the mapped location of the Wildomar fault that transects the site. New digital mapping indicates that a splay of Wildomar Fault terminates before the eastern boundary of the site, then steps over and continues across the southern portion of the property. This supplemental investigation is intended to evaluate the location of onsite faulting and provide updated recommendations pertaining to the previously established fault setback zone for the property (Engen; 1998). This supplemental investigation is intended to meet requirements of the Alquist-Priolo Zoning Act for the State of California, requirements ofthe County of Riverside, and the City of Temecula in conjunction with previous reports for the site (Appendix A). SUMMARY Based on our literature review (Appendix A), field investigations, and geologic analyses, it is GSl's opinion that development of the site is feasible from a geologic viewpoint, provided the recommendations contained herein are implemented. This supplemental investigation indicates that active faulting (Le., movement within the Holocene epoch, or last 11 ,OOO:!: years [Hart and Bryant, 1997]) crosses the southern portion of the property. Accordingly, a revised fault setback zone has been established for the property based on subsurface conditions encountered during this investigation. This additional subsurface exploration, after review by the City of Temecula and/or the County z.. II I I I , I I , , ., , , , , , , , " , , of Riverside, should meet the requirements of the Alquist-Priolo Zoning Act concerning onsite faulting. Unless specifically superceded in this report, the conclusions and recommendations in previous reports for the site (Appendix A) remain pertinent and applicable and should be appropriately implemented during planning, design, and construction. The opportunity to be of service is sincerely appreciated. If you should have any questions, please do not hesitate to contact the undersigned at (909) 677-9651. Respectfully submitted, GeoSolls, Inc. ~~~e~vl~ Project Geologist Reviewed By: o n p~r2~ Engineering Geologist, CEG 1340 TAG/JPF/mo Distribution: (4) Addressee James and Mardi Margiotta File:e:\wp7lmurrlrc2900l2963a.sgf w.o. 2963-A-SC Page Two ~ GeoSoils, Ine. I I I I I I I I 'I I , I t I I I 'I I I TABLE OF CONTENTS SCOPE OF SERVICES ................................................... 1 SITE DESCRIPTION ..................................................... 1 PROPOSED DEVELOPMENT .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 BACKGROUND AND PREVIOUS INVESTIGATIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 FIELD STUDIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Lineament Analysis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 REGIONAL GEOLOGY ................................................... 4 Regional Geologic Setting ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 SITE GEOLOGY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Artificial Fill - Undocumented (Map Symbol - Afu) ........................ 4 Quaternary Colluvium (not mapped) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Quaternary Older Alluvial Deposits - (Map Symbol - Qoal) ................. 5 Quaternary Pauba Formation (Map Symbol - Qp) ........................ 5 FAULTING AND REGIONAL SEISMICITY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 . Seismic Shaking Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 SUMMARY OF GSI TRENCHES.. .. .. .. .. .. .. . . . . .. . . .. . .. .. . .. .. .. .. . . . .. 10 GROUNDWATER....................................................... 10 LIQUEFACTION POTENTIAL............................................. 10 CONCLUSIONS AND RECOMMENDATIONS ................................ 11 PLAN REVIEW .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 INVESTIGATION LIMITATIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 FIGURES: Figure 1 - Site Location Map ......................................... 2 Figure 2 - California Fault Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Figure 3 - Digital Fault Zone Map ..................................... 8 ATTACHMENTS: Appendix A - References ................................... Rear of Text Appendix B - EQFAUL T, EQSEARCH, AND FRISK89 PRINTOUTS .. Rear of Text Plate 1 - Geologic Map. . . . . . . . . . . . . . . . . . . . . . . . . . . . . Rear of Text in Pocket Plates 2 and 3 - Trench Logs T-1 and T-2 . . . . . . . . . . . . . . Rear of Text in Pocket GeoSoils, Ine. I I I , I I I I 1 I II I I I I I I I I SUPPLEMENTAL GEOLOGIC/FAULT INVESTIGATION LOTS 19 AND 20. TRACT 9833-3 CITY OF TEMECULA, RIVERSIDE COUNTY, CALIFORNIA SCOPE OF SERVICES The scope of our services included the following: 1. Review of available geologic data for the area (Appendix A). 2. Geologic and geomorphic site reconnaissance. 3. Review of stereoscopic infrared aerial photography, (Appendix A) and performance of a lineament analysis for the site. 4. Emplacement of two trenches (totaling approximately 420:!: feet), across the property, and related formal geologic documentation of subsurface conditions exposed (See Plates 2 and 3). 5. Analysis of the data collected. 6. Preparation of this report and accompaniments. SITE DESCRIPTION The subject site is an irregular parcel consisting of approximately :!:6 acres. The parcel is located east of Jedediah Smith Road in the City ofTemecula, Riverside County, California (see the Site Location Map, Figure 1). In general, the main portion of the property is located east of Jedediah Smith Road and is bounded on the north and south by existing properties and on the east by an EMWD easement. The site is generally characterized by gently rolling hills. Site drainage is generally by sheet flow and by incised drainage corridors that lead to the south. General relief of the proposed development area is approximately 109:!: feet, ranging from a high of 1, 178:!: feet (MSL) in the northeastern portion of the property to a low of 1 ,069:!: feet (MSL) to the southeast. PROPOSED DEVELOPMENT Preliminary land use plans indicate that typical cut and fill grading techniques would be utilized to prepare the site for construction of two single family residences, and associated utility and roadway improvements. It is our understanding that the buildings would be one- and/or two-story structures, using typical wood-frame construction with slabs-on- grade and continuous footings. Building loads are assumed to be typical for this type of relatively light construction. Sewage disposal is to be accommodated by a septic tank and leach field system. The need for import soils is unknown at this time. GeoSoils,Ine. ~ I I I I I I , I ..J I I I , -. , I I t o ~ "'" ~. 'V ,! <\ /\, <\ / ~'" V" -, Base Map: Alquist-Priolo Earthquake Fault Zones, 7.5 minute, Temecula and Pechanga Quadrangles, topographic base USGS 1968, photorevised 1988. I :9 ~.,-.. ~"..I' ,," " ''''''. -. t....:;. . . . - . .c ,. or ,_ ..... _,''';'' _,_..' ..,.,..... ," ._.'t~c w.o. 2963-A-SC I SITE LOCATION MAP o ~ 2000 I 4000 I Feel Figure 1 I Scale I~ I I I I I II I I I I I I I I I I I I I BACKGROUND AND PREVIOUS INVESTIGATIONS The adjacent site was previously investigated by Pioneer Consultants (1980). It is our understanding thatthis report was never submitted to the goveming agencies for approval. However, mapping and subsurface exploration for this investigation did extend onto the property covered under this investigation. In addition, EnGen Corporation (1998), provided a geotechnical engineering study (Appendix A) for the property which established a 100 foot building setback. zone across the lower portion of Lots 19 and 20. No subsurface exploration was conducted for that study. These previous studies examined the site and adjacent property on a preliminary basis and concluded that development of the site was feasible from an engineering and geotechnical viewpoint. FIELD STUDIES Field studies conducted during our evaluation of the property consisted of the following: 1. Initial geologic and geomorphic site reconnaissance. 2. Emplacement of two trenches (totaling approximately 420:!: feet), across the entire width of the buildable areas of lots 19 and 20. This subsurface investigation included formal geologic documentation of subsurface conditions exposed. These fault finding trenchs were logged by a geologist from our firm. The locations of . GSI's trenches from this supplemental investigation are shown on Plate 1. Logs of the GSI trenches from this investigation are shown on Plates 2 and 3. 3. Appropriate engineering and geologic analyses of data collected and preparation of this report and accompaniments. Lineament Analvsis In order to identify possible unmapped faults and to evaluate topographic expressions of the published fault trace, a lineament analysis was performed. As listed in Appendix A, the imagery used were stereoscopic "false-color" infrared aerial photographs (scale 1 "=3333). Photographic lineaments are generally classified as strong, moderate, or weak. A strong lineament is a well defined feature that can be continuously traced several hundred feet to a few thousand feet. A moderate lineament is less well defined, somewhat discontinuous, and can be traced for only a few hundred feet. A weak lineament is discontinuous, poorly defined, and can be traced for a few hundred feet or less. A moderate lineament corresponding with the break-in-slope was noted transecting the site during our analysis. James and Mardi Margiotta Lots 19 and 20 Tract 9833-3 File: e:\wp 7\murrlrc2900\2963a.sgf w.O. 2963-A-SC January 31, 2001 Page 3 -5 GeoSoils, Ine. I I I , I I I , , I I I I I I , I , , REGIONAL GEOLOGY Reaional Geoloalc Settlna The subject property is located within a prominent natural geomorphic province in southwestern California known as the Peninsular Ranges. It is characterized by steep, elongated ranges and valleys that trend northwestward. The Santa Ana Mountains lie along the western side of the Elsinore fault zone, and the Perris Block is located along the eastern side of the fault zone. The mountain ranges are underlain by pre-Cretaceous metasedimentary and metavolcanic rocks and Cretaceous plutonic rocks of the southern California batholith. Tertiary sediments and volcanics, and Quaternary sediments flank the mountain ranges. The Tertiary and Quaternary rocks are generally comprised of nonmarine sediments consisting of sandstones, mudstones, fanglomerates, and scattered volcanic rocks. Uplift on the regional faults, and erosion has resulted in the incision of the older rocks, and subsequent deposition of coalescing alluvial fans in the valleys. SITE GEOLOGY Geologic units identified within the study area are: artificial fill, younger and relatively older colluvium, older alluvium, and the Pauba Formation. Supplemental descriptions for subunits within the Pauba Formation encountered in the subsurface explorations are shown on Plates 2 and 3. The major geologic units in the site are shown on Plate 1, and' are generally described, from youngest to oldest below: Artificial Fill - Undocumented - (MaD Svmbol - Aful Undocumented artificial fill occurs locally within the site and is generally associated with the EMWD easement and onsite dirt roads. Also present is undocumented (uncompacted) backfill of the current fault finding/exploratory trenches. The fill materials are light to dark brown and light gray silty and clayey sands, derived onsite. These unengineered fill materials are dry, loose and are potentially compressible and may settle appreciably under additional fill or foundation and improvement loadings. These materials are unsuitable for support of structures and/or improvements in their existing state. Quaternarv Colluvium (not maDDed) Colluvium mantles the older alluvial and bedrock deposits onsite. A relatively younger colluvial unit was noted mantling the artificial fill materials in trench T-1 (see Plate 2). The colluvium ranges in thickness from about 2:!: to as much as 3:!: feet in the southern portion of the site. The colluvium is generally silty, fine- to coarse-grained sands and silts with some pebbles, and locally abundant gravels. These materials are dry to damp, and loose and porous near the surface. Typically, colluvium has a very low to low expansion James and Mardi Margiotta Lots 19 and 20 Tract 9833-3 File: e:\wp7lmurrlrc290012963a.sgf W.O. 2963-A-SC January 31 , 2001 Page 4 ~ GeoSoils, Ine. I I I .1 J I I I I I I I I I I I I I I potential. These materials are unsuitable for $UPport of structures and/or improvements in their existing. state. Quaternarv Older Alluvial DeDosits - (MaD Svmbol - Qoal) Older alluvium mantels the bedrock materials in the upper canyon areas and comprises the majority of the southern part of the site. These sediments are generally silty to clayey sands, and are generally light to dark brown to reddish brown, dry to damp, and medium dense to dense. These sediments are generally massively bedded, and generally flat lying. These materials are visually classified as having a low to possibly medium expansion potential. Due to the consistency and density of these older alluvial deposits they are considered suitable for support of structures and/or improvements after remedial removals of surficial deposits have been completed. Quaternarv Pauba Formation - (MaD Svmbol - QD) Relatively older bedrock materials ofthe Pauba Formation underlie most ofthe study area at depth. The bedrock is composed of silty sands, to clayey sands with minor pebbles and gravel, to sandy silts. The bedrock is generally grayish brown to light gray to dark brown, dry to damp, and medium dense to dense. Additionally, it is medium to thickly bedded and massive. It is generally flat lying to gently inclined to the south-southeast. These sediments may reach several tens offeet in thickness. These materials are visually. classified as having a low to medium expansion potential. These sediments are Pleistocene in age (Kennedy, 1977). FAULTING AND REGIONAL SEISMICITY The site is traversed by an "Earthquake Fault Zone" associated with the Wildomar Fault (considered part of the Elsinore fault zone) as indicated in the Alquist-Priolo Earthquake Fault Zoning Act (Hart and Bryant, 1997). In general, the site is situated in an area of active as well as potentially-active faults. The acceleration-attenuation relations of Joyner and Boore (1982a and 1982b), and Campbell and Bozorgnia (1994) have been incorporated into EQFAULT (Blake, 1989a). For this study, peak horizontal ground accelerations anticipated at the site were determined based on the random mean and random mean plus 1 - sigma attenuation curves developed by Joyner and Boore (1982) and Campbell and Bozorgnia (1994). These acceleration-attenuation relations have been incorporated in eQFAUL T, a computer program by Thomas F. Blake (1989), which performs deterministic seismic hazard analyses using up to 150 digitized California faults as earthquake sources. The program estimates the closest distance between each fault and a user-specified file. If a fault is found to be within a user-selected radius, the program estimates peak horizontal ground acceleration that may occur at the site from the upper bound ("maximum credible") and "maximum James and Mardi Margiotta Lots 19 and 20 Tract 9833-3 File: e:\wp7lmurrlrc2900\2963a.sgf w.o. 2963-A-SC January 31 , 2001 Page 5 1 GeoSoils, Ine. I I ~ I I I I I I I I I I I I I I I I I I probable" earthquakes on that fault. Site acceleration (g) is computed by a user-selected acceleration-attenuation relation that is contained in EQFAULT. Based on the above, peak _ horizontal ground accelerations from an upper bound event may be on the order of 0.55g to 1.12g, and a maximum probable event may be on the order of 0.55g to 1.02g. The major faults and fault zones in southem California that could have a significant effect on the site should they experience activity are presented in Appendix B, which includes the pertinent computer printouts of the EQFAUL T program. The possibility of ground shaking at the site may be considered similar to the southern California region as a whole. The relationship of the site location to these major mapped faults is indicated on the Fault Map of Southern California (Figure 2). In addition, a digital fault zone map of the site, provided by the County of Riverside, is included as Figure 3. ABBREVIATED FAULT NAME APPROXIMATE DISTANCE MILES (KM) Casa Lorna-Clark (San Jacinto1 22 ~35\ Chino 33/521 Clamshell - Sawoit 38 1611 Coronado Bank-Aqua Blanca 45 /73\ Covote Creek (San Jacinto) 34/55\ Elsinore o to\ Glen Helen-Lvtle Creek-Claremont (San Jacinto' 24139\ Hot Sorinas-Buck Ridae ISan Jacinto) 25 /40\ La Nacion 44 /70\ Newnart - Inalewood - Offshare 29/47\ Pinto Mountain - Moronao 48m) Rose Canvon 29/47) San Andreas rCoachella Vallev\ 48 1771 San Andreas (S. Bernardino Mtns\ 42/68\ San Goraonio-BanninQ 35/57\ San Jose 54/87\ Sierra Madre-San Fernando 56 190\ Whittier-North Elsinore 38 /611 Historical site seismicity was evaluated with the acceleration-attenuation relations of Campbell and Bozorgnia (1994) and the computer program EQSEARCH (Blake, 1989b, James and Mardi Margiotta Lots 19 and 20 Tract 9833-3 File: e:lwp7\murrlrc2900\2963a.sgl w.o. 2963-A-SC January 31 , 2001 Page 6 B GeoSoils, Ine. I =1 r.r. 1 =1: - , :......, I ;;; ~'Ii =::0:; . <=> - ! ~:.... ; <> "'j ~ ~II ~ ~ <> ~ ~: I ~. =1' - - . ~ <> I ~ :;11. ~ - I .....:::: . - ' , c ;1 I I E 9Jn6!:1 01 =~ I ....> --- c- I "-'= "" c- --- ~ = =~ I en I I I I <D~ ~ :z ,..., > 0 c- = ~ en c- _ ~ - :z :z 0 c- = - :>> ,..., :z ,..., ~ ..,.., > > = = c- c- ~ ~ '" '" o 0 :z :z ,..., ,..., 11 I I J: <---- <:> ~ ~ '" - ~ ~ ~ "'- - , "'II '" ~ -- <:> -~ <:> '" ~ n '" - - '" '" <:> -.....--.....""'--....- ::.;:::.::;:-:~ __ ,.._ :0-- --.. -----.. .....--_._....~~ ............ ..!!I...... -=- ...- -.- .... . _.__0- .._ .. ... ..,. ...-....-.. ... __:a ..._...... -- ... --.....--.-... -... -.... -... :=-~:;;=.."~~ - - --- --....-.... -.--.--.... .. .... _........- ......... .. -........ -- --- -- -...- .. 5...... _.... 5 --co _ eo..............._ :0 _....... ca....... -..... -....- -.. 0- _._ !!I _... _... - ...... _..... .. -co _ II _ '" __ ... .. .. -. ............ -......... -s"" ............ -.. -- .... ..............- ....._.... __!!i ... .. .. ... .... _...._-, _... __...__a.. ----..-...... .. or__ _ ___.... - __c.... -........................ ... --........... -.: :- ::: ;:-:. ... --... ---- ....... -...... - .._ _.... n -... --.... --- PO c=t_... -._co :: :~:~ -=-.:..--: ....0 _...... _.. ... --.-....- :~::-: :....::: =-. .. --- -.......... --- ---...... ---.... .... .... - -.- ..... - - .. -... -... ..... - - ...:..: ;;:=:.:":: .--.!!!t-.. _..... : : =-=:.....=--=- _. -.--.. - --. _. 0_.. _... :..;- . II I I I I I I I I I I I I I I I I I I updated to June, 2000). This program performs a search of historical earthquake records . _ fQr magnitude 5.0 to 9.0 seismic events within a 100 mile radius, between the years 1800 to 2000. Based on the selected acceleration-attenuation relationship, a peak horizontal ground acceleration is estimated, which may have affected the site during the specific event listed. Based on the available data and the attenuation relationship used, the estimated maximum (peak) site acceleration during the period 1800 to June, 2000 was 0.21 g. In addition, site specific probability of exceeding various peak horizontal ground accelerations and a seismic recurrence curve are also estimated/generated from the historical data. Computer printouts of pertinent portions of the EQSEARCH program are included in Appendix B. A probabilistic seismic hazards analysis was performed using FRISK89 (Blake, 1989c) which models earthquake sources as lines and evaluates the site specific probabilities. Based on a review of these data, and considering the relative seismic activity of the southern California region, a peak horizontal ground acceleration of 0.40 g was calculated. This value was chosen as it corresponds to a 10 percent probability of exceedance in 50 years (or a 475 year return period). Computer printouts of pertinent portions of the FRISK89 program are included in Appendix B. Seismic Shakina Parameters Based on the site conditions, Chapter 16 of the Uniform Building Code (International Conference of Building Officials, 1997), the following seismic parameters are provided. . I UBe TABLE/FIGURE DESIGNATION I . FAULT PARAMETERS I Seismic zone (oer Fiaure 16-2*) 4 Seismic zone factor Z (oer Table 16-1*) 0.40 Soil Profile Tvoes (oer Table 16-J*) Sn Seismic Coefficient C. (per Table 16-Q*) 0.44 N Seismic Coefficient C. (per Table 16-R*) O.64N Near Source factor N. (per Table 16-S*) 1.30 Near Source factor No (per Table 16-T*) 1.60 Distance to Seismic Source o mi. CO km\ Seismic Source Tvoe (oer Table 16-U*) B UDDer Bound Earthauake M...6.8 * Figure and table references from Chapter 16 of the Uniform Building Code (1997). James and Mardi Margiotta Lots 19 and 20 Tract 9833-3 File: e:\wp7\murr\rc2900\2963a.sgf w.o. 2963-A-SC January 31, 2001 Page 9 \t GeoSoils, Ine. I I I I I I I I I I I I I I I I I I I SUMMARY OF GSI TRENCHES As shown on Plate 1, Trench T-1 and T-2 extend across the property from the northeast to the southwest, covering the entire width of the buildable area of lot 20 and traversing through lot 19. Exploratory trenching of the site was conducted in November of 2000. The City of T emecula was given advanced notice of the geotechnical investigation and invited to review the onsite exploratory fault trenching in the field, however, no one from the City came to review the trenches. The trenches were 10:!: to 16:!: feet deep, emplaced into bedrock and the relatively older alluvial deposits onsite. Trench T-1 was approximately 170 feet in length, T-2 was approximately 250 feet in length, and both trenches were logged by a geologist from our firm at a scale of 1 "=5' (see Plates 2 and 3). Evidence for active faulting was encountered during our underground investigation and an appropriate revised setback zone was established based on this subsurface investigation of the property (see Plate 1). GROUNDWATER Seeps, springs, or other indications of a high groundwater level were not noted on the subject property during the time of our field investigation. A high groundwater elevation of 1015 mean sea level (msl), California Department of Water Resources (1971), was recorded in state well No. 8S/2W-17M1S, in the Pauba Valley below the site. Although. indications of a shallow, or "perched" groundwater condition (Le., where relatively impermeable sediments underlie relatively permeable sediments filled with water) were not noted, due to the contrasting nature and permeability of the onsite earth materials, the possibility offuture,localized perched water conditions car:mot be precluded. Should such conditions become apparent in within the site area in the future, additional recommendations for mitigation may be provided upon request. LIQUEFACTION POTENTIAL Seismically-induced liquefaction is a phenomenon in which cyclic stresses, produced by earthquake-induced ground motion, create excess pore pressures in soils. The soils may thereby acquire a high degree of mobility, and lead to lateral movement, sliding, sand boils, consolidation and settlement of loose sediments, and other damaging deformations. This phenomenon occurs only below the water table; but after liquefaction has developed, it can propagate upward into overlying, non-saturated soil as excess pore water dissipates. Typically, liquefaction has a relatively low potential at depths greater than 45 feet and is virtually unknown below a depth of 60 feet. Liquefaction susceptibility is related to numerous factors and the following conditions should be concurrently present for liquefaction to occur: 1) sediments must be relatively young in age and not have developed a large amount of cementation: 2) sediments James and Mardi Margiotta Lots 19 and 20 Tract 9833-3 file: e:\wp7\murrlrc2900\2963a.sgf w.o. 2963-A-SC January 31, 2001 Page 10 \z.... GeoSoils, Ine. II . I I I I I I I I I I I I I I I I I I generally consist of medium to fine grained relatively cohesion less sands; 3) the sediments must have low relative density; 4) free groundwater must be present in the sediment; and 5) the site must experience a seismic event of a sufficient duration and magnitude, to induce straining of soil particles. The condition of liquefaction has two principal effects. One is the consolidation of loose sediments with resultant settlement of the ground surface. The other effect is lateral sliding. Significant permanent lateral movement generally occurs only when there is significant differential loading, such as fill or natural ground slopes. Few such loading conditions exist on the site. In the site area, we found there is a potential for seismic activity, however, the site and the alluvial sediments were silty, fine to coarse grained, massively bedded and become dense with depth. Inasmuch as three or four of these five required concurrent conditions discussed above do not have the potential to affect the site, our evaluation indicates that the potential for liquefaction and associated adverse effects within the site is low, even with a future rise in groundwater levels. Therefore, it is our opinion that the liquefaction potential does not constitute a significant risk to site development. CONCLUSIONS AND RECOMMENDATIONS Based on our review, field investigation, and geologic analyses, it is GeoSoils Inc.'s opinion' that development of the site is feasible from a geologic viewpoint, provided the recommendations contained herein are implemented. Recommendations for mitigation of the fault trench backfill should be provided by the geo!echnical consultant. This supplemental investigation indicates that the Wildomar fault that crosses the southern portion of the site (Figure 1 and Plate 1) is likely active, according to the State of California (Le., movement within the Holocene epoch, or last 11,OOO:!: years [Hart and Bryant, 1997]). Habitable structures should not be located within the revised setback zone next to this fault, as depicted on Plate 1. Further fault locating trenches in this area or vicinity may serve to reduce the currently proposed setback zone. PLAN REVIEW Final grading plans as well as foundation and improvement plans should be submitted to this office for review and comment, as they become available, to minimize any misunderstandings between the plans and recommendations presented herein. In addition, foundation excavations and earthwork construction performed on the site should be observed and tested by this office. If conditions are found to differ substantially from those stated, appropriate recommendations would be offered at that time. James and Mardi Margiotta Lots 19 and 20 Tract 9833-3 'File: e:lwp7lmurrlrc2900l2963a.sg1 W.O..2963-A-SC January 31, 2001 Page 11 \~ GeoSoils, Ine. I I I I I I I I I I I I I I I I I I I I INVESTIGATION LIMITATIONS The materials encountered on the project site and utilized in our investigation are believed representative ofthe total area; however, soil materials may vary in characteristics between excavations. Inasmuch as our investigation is based upon the site materials observed, and engineering and/or geologic analyses, the recommendations are professional opinions. It is possible that variations in the soil conditions or faulting could exist beyond the points explored in this investigation. Also, changes in groundwater conditions could occur at some time in the near future due to variations in temperature, regional rainfall, and other factors. These opinions have been derived in accordance with current standards of practice, and no warranty is expressed or implied. Standards of practice are subject to change with time. GSI assumes no responsibility or liability for work or testing performed by others. In addition, this report may be subject to review by the controlling authorities. James and Mardi Margiotta Lots 19 and 20 Tract 9833-3 File: e:\wp7lmurrlrc2900\2963a.sgf w.O. 2963-A-SC January 31, 2001 Page 12 \'\ GeoSoils, Ine. I.' I, I I I I I I I I I I I ,I I I 'I I I APPENDIX A REFERENCES \"5" I. I I I I , I I I I I I I I I I I I II . APPENDIX A REFERENCES Blake, T.F., 1989a, EQFAUL T, A computer program for the deterministic prediction of peak horizontal acceleration from digitized California faults; Updated through 1997. _, 1989b, EQSEARCH, A computer program for the estimation of peak horizontal acceleration from California historical earthquake catalogs; Updated through June 2000. _, 1989c, FRISK89, A computer program for the probabilistic estimation of seismic hazard uSing faults as earthquake sources; Updated,1997. California Department of Water Resources, 1971, Water wells and springs in the western part of the upper Santa Margarita River watershed, Riverside and San Diego Counties, California, Bulletin 91-20, August, 377p. EnGen Corporation, 1998, Geotechnical engineering study, proposed single family residences, Lots 19, 20 and 21 of Tract 9833-3, City of Temecula, County of Riverside, California, project number T1360-GS, dated March 11. Hart, EW. and Bryant, WA, 1997, Fault-Rupture Hazard Zones in California, Alquist-Priolo. Earthquake Fault Zoning Act with Indexto Earthquake Fault Zones Maps; California Division of Mines and Geology Special Publication 42, with Supplements 1 and 2, 1999. International Conference of Building Officials, 1997, Uniform building code: Whittier, California, vol. 1, 2, and 3. Kennedy, M.P., 1977, Recency and character of faulting along the Elsinore fault zone in southern Riverside County, California: California Division of Mines and Geology, Special Report 131, 12p. United States Department of Agriculture, 1980, Aerial photographs, project no. 615020, flight date August 10th and 20th, flight line 180 and 580, photo Nos. 29-32 and 184 and 185 respectively, scale 1 "=3333':!:. u;, GeoSoils, Ine. II . I ;1 I I I I I I I I I I I I I I 'I I APPENDIX B . EQFAULT, EQSEARCH, AND FRISK89 PRINTOUTS n o o ~ u )> AJ VJ o z o ---rJ ~ )> X ~ C ~ fT1 )> AJ -j I o C )> ^ fT1 VJ :s::: )> x :s::: c :;:;: (') :::D r'l o ill r r'l r'l )> :::D -1 I o C )> ^ r'l Ul :s::: )> X :;:;: C :;:;: ""D :::D o ill )> ill r r'l r'l )> :;0 -1 I o C p;- ^ r'l Vl PEAK HORIZONTAL ACCELERATION (9) 0 0 c::> - ~ . . . - . . . - . . IIIIIII , I 1111111 I I 11111l! x " x ~t,;~ XX<~~ 1111111 I I 1'11111 I I I I Illd PEAK HORIZONTAL ACCELERATION (9) 0 0 c::> . - . . . - . I , r I 111111 , n x x x x "x ';<X x loI' x'1ll<~- x lit' x o o o c::> o (f) ~ z_ Oo ", ~ ~. ~ o o - o o o o o o - o o (f) ~ z_ Oo ", ~ 3 ~ o o - o o o ~ -8 9lBld c... o aJ Z o N to Q) LN I }> I If) (') >= -I -I C o 1'1 LN LN .J>. OJ o o z r o Z C) -I C o 1'1 ~ ~ --.J ~ ~ OJ LN :E ~\ II I I I I I I I I I I I I I I I I I I LQG_N_ 3.669 - O.755M 100 10 ~ z ~ a::: L5 >- '-... 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BR9W 01 TCI-I I\~( 1--\ ? r\ 0 rs \'\ 0"( r:) ,,( \ 0 \\ P 0 r\ ,,( ~\ \ 0"( ~\9; ~ /' ,/ ' / / / / / ,., / / / / / / / / ." 'r' \ '/ v "" J..". ~) L '. / / / ~'\/ ,,:6 ~~/ bo.~~~' S\;/ t~ ~/ ......\ V , .......( j r) ~~ / \ 0 ~ \J 3 0 ~" ~:..,." 0 ~ / -( ~), ~j . ~ / / 4." ,":f)N(:R[ T[ /' /~ :..,) .~ ~.. I 1 6' __ __ __.__ ~-- ------- ------. ------- -1 , . , , , .A.' Q' I ';)' ~2 .. ~ . 2 ~_I-___~ ... . ~-- - -------r---aa---1 I I 1\ B ,( ,,'1 r) \ 0 } rJ.10t. ~ 6 ~r:) 0 ~S/t) -1 r\ ~ B J t) · \d t) ~}l f.-J .... ~ ~ ", ',,- :-::.. ~ ~..., /~ !: J9(( , ~~ ~ y -,L t.), ~-- -y ~ I \ I --\ \ ~ ~ I' 'f 1-1" ------- / / / / / /. / / DRIVEWAY OETAIL tf!O T "'0 5C Ai [ LOOKING OO\M'IGRADF ( ~ COtlPACW ~ I'IAfI\I( / ~ " \ , ..I " 1 % M I ~ ~ '" -.-- "1 ,/ / / / CONSTRUCTION NOTES: CRAP/II(' .)~f/tLE o 20' 40' t t t (]) @ Q) G) @ @ CONSTRucr 26' RESIDENTIAL CONCRETt DWY APPROAC~I PER CITY OF TEMECULA STD. DWG. NO: 207 I ,/ / / / CONSTRUCT 126 LF RETAINING WALL, h'=2' -6' MAX, PER SEPERA 7E PfRMI T -_ 1. _ a.- "'___"f' tI LEGEND ~ @ '''JDIC/~ r[s CONSTRue nON NO iE INDICA res SANDBAGS, 2 BAGS H/Gf.~ INDICA rrs SIt r FENCE INDICA res DRAINAGE INLET ''''OfGA r[s CONCR[ T[ INDICA rES FINfSJ-1 SURF ACE INDICA rES FLOWliNE iNDICA rES fUCH POIN T iNDICA rrs GRADE BREAK INDICA T[S TOP OF WALL INDICA rrs TOP OF FOO nNG / / ) / .. T nMCI < , INSTALL 12" X 12- BROOKS BROTHERS DRAINAGf INL E T OR APPROVfD EQUAL CONS TRue T 16' '.WOE X 4" DEfP, CONCRf r[ DRI V[WA Y ON COMPACTED NA nVf, PER DETAIL J-ItREON INSTALL J LF OF 6" PVC DRAIN, THROUGH RETAINING WALL, SLOPE = -2.00" MINIMUM TO EdGE OF DWY. t i CONSTRUCT J~ WIDE GUNITE: DOWN DR~/~ TO 80 r"rOM OF EXIS'nNG SLOPE PER DETAIL HfRfON. A r au rtET, PLAcr 6" DIA. ROCK OR APPROVF:O EQUAL, 4' X 4' X l' CONSTRUCT 4 N DECP CONCRETE SLAB ON COMPAC,(ED NA TIV[ INSTALL SAND BAGS, 2 BAGS HIGH (SHE EROSION CONTROL NOTES, S,""I[E'T 1) SAWCUT AND REMOVE 26' LF OF Ex/s'nNG AC BERM AND A MINIMUM OF ASPHAL r AS NECCESSARY TO CQNsr DWY r I ::"1 ) EARTHWORK / / / / / / / ,/ / ,/ // -\ ,// \\ 0 -r --1 ~/2 c ~~ / ~) G :IS/oJ -r 1\ c !) / f) \ ::)D . ~J\ 6 ~ ,..111111.1.. Area under purView Of thiS report LEGEND Artifical fill . r--------, L___ -.J . FS FL f-fP GB TW Tr Af Qoal Qp Quaternary older alluvium 1\ 9 -( ,-1 j' J } r> :1 6 t ~) 6 y r)\ Q '~)' 8 --' ~ . \ r ~ rJ , . bOI ,,:\6 I 80 uJ Quaternary Pauba Forrnation (j) @ @ S t_ il '-- ~_ ~ .......... --- Geologic contact o Surveyed fault location --- · .-. Location of fault zone ........... Location Of faUlt setback zone CUT JOO CY FILL JOO C Y HLe civil_ enl1i~erin!l 4t661-~1ERWfl'00[ N(jl}j. ~IT 225 (900) 676-6225 (900~76-7976 FA) I~t CdifoolKJ 92~ , 1 - 800 422-4133 / / / / ,......... 01 "'-.. If) o "- (t) o o ~ . o o c:{ 0:: '-' z G:" / 'tWO WORKING DAYS BEFORE YOU DIG . Contractor CONs-rRUCTION RECORD lx~~ires 6/;391.90 ) K A IV . ~ ~ (~ ~ (), C: her: Ked ~ ~ y I)rnwr' ~1, TEMF CULA "- DEPARTMEN-r OF PUBLIC WORKS [)estgr'ed Hi --~ -.... ~- H. CORREA D. GINN f-f. CORREA PLANS PREPARED UNDER THE SUPERVISIO~J OF /1 Ie:; t.J. .5 I / DATE BY REVISIONS DATE Ace, D BENCHMARK C rfY OF SCALE OA TE: - RECOMMENDED BY: __ ._ HORIZONTAL SilU r 2 01 2 DArE: AS BUlL TIP!<EC/SE GRADING PLAN 30655 JfDfDIAH SMI TH ROAD PARCELS 191 201 \\\ANO 21 OF TRACT 9833_3 1"=40' . Date . .. '. \. ... ~- --- --.~-- -. - -- - - . VERTICAL HECTOR L. CORREA R . C . E . f\J O. __ . ~~.J.q_~ _ _ NA " E L E V ,A .1 I ,~O' N ',~ft~) * I ~ L IE: V A T I ,0 ~ (f t.) . I :' .. . . t' " I,\- . T: , ';,t J ~ .:'..< , '.' ". :'<,''''/,~;!'i';;r;r'f' , , STATION' NUMBER' , '. t" . 1105, ..........,. 1100 ---, 1095 ~ 1090 ~ 108 5 ........ T-1.' i ; STATION NUMBeR 1090 ~ 1085 ---- 1080 ....... ; 1q!~ -.... 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"", '" u" :,';i':':.. ,." · I:'. ...~ ~ '''ir'' ':":'~?J'~fi1t'~~J(""''''' ", · I " :. ' '. .' ;.::,i);.; ". '!.' ...;;c)L.~:r;.:\:~:~,:,..;:,. #- .. - II> Ii ~ .. \, , t. .-.-" P · ~, · #- ~_..' I: ,. .Q~' .. " t1 " ' , - 1/1.,. -' t ,,~. ' .. p , ~ ' 0 1 .. , I ~', , ~. i.. " '" 1 .y- ,,, ~" -- ." . I, *. ... .. ~. fJ ~ · ., 7. --.....:.. "'.:.'. '.." ; I · · .. ~ · -::--..... , ',' · Q p' Stage II carbonates ' '. : . , · · .'.. · ~ L ---!... I ", }. ~ ......... J7 · I I: ~ . '"" v r1 1J' (/ ~ l /L o ..li> '+:;1 \. 7' k- \'~ \ '/0- '" ^~ / W'" ~ . ~. I" \...... · f)'" .. t.:> : 1>: " ',~,,".^./ , .u .L7\J~'~',.,:::, , ;': ~.......- I) , ''': ....1'-~-lt4.",.,.t~ l.... ~ " ~ p -'..... ~ I . . lit t I,) :'''. :';' /II ,,' , v '. * --... -'," 'Qeol ~ . . ~ o .., 1:;. o '(7 ..> o · '4 'Q.p; pt o (;? II (J ~ : .' .... . , . ,~ ~ (;1 <> t" o ~ Q ~ -- t) t' " ~. (;I .. o ,. ~ __ '~;"~ . ~. ~TifJ!l"';:T[rii0 · <> 'C7 ,:-iIF~ ,-.::;- ~ L,/ 1\"1 , ' 'j~~ #- , ..~. ~/~),.,..' I \ /' ";I" \ tt 1'0 r\ K..... ~ · ',t Y--:7 .;'""" ~ ....... r". tf 1:=>. ~ '.. ':' ~ . l7 Patoesol' ' ...... ....... · '" ~ Shige II ear~onateG " · ."',,....4.~..: ~ . t7 ~.........:.-. ,,' l .', ',', : "'; " I " 120,,- I , ~ j ; I .. ~tij. I "' ~ fO. ' .' . '. ,'.,;- , . " &I ~ '" ............... .- ~-~ o\J 1~O, I 140 I I ;'S'OUTHEAST WAIl~',' 150 1160 I 170 1 " . N5.5E ............... \it; I FlawE)'( structure Roll-over ~ ~ vi ~: 1'40 I 130 L STATION NUMBER, I 6 Q e> o , · \r?~.- p , ., ,~~~- .~ r yo _ 1~\,- ~ : . q ~I j),'J' ') ! -- ~ --. 4?~ Fault Zone --P') j ')' · Op I. .1 Q tl1 (' ).)( ~ 9 J. t? () \ , () '/)). -----.....; I. . J> 160 I t. Qcol p ,170 I 150 I NORTHWEST WAL.L" 6 . (.) ~ " ......... 10 gO ~\ ,~. /. Pl()~et atruature .'\ilI. 41 '. ../., '.0.,.. b ~. () r,..... 17'" _~ .. · ~ · .. ~..' · . a'(J 0 r · '.. ..' \ q '. 11 4 .' Q '" \ ( ( , \ ,~. . ~~". (. .). ,~/~ ~ . Op · · . . · , ~ \Q J?~ ) . · ~ , 1_ _. · I - 101'5 6 IE L It ',\I: A T I o N (ftJ) f.1 Qp ~ ... () , . p P .'\ .' ~...~--.,- -- .1085 fJ I.' ~ () N55E': I , / Qp o ......... 1 080 , " t,;; () o \~~ lEGBND T~1, T-2" " .)I. () t'/ i> ~ ~ '). , , . , : 'Afu.".;,,'. .'; AtlUlgf~' Em ~ un~o~umleot~~;allty SAND. dart< grayish brf;)Wn:.1"Q~'A:4f2 to dark brbwn 10YR ' . . .{ ,.." :". ,':> ' r "I , " . ...~:'} ,,':'\ ,;,:'- .....;. ," . -" ~ ,; ';,:,~I:" ' ":. ' , ,".;. 3/3, drY to qamp," laosa; abundant'foots anq rootlats~ ," r:. . : .' . ,'. ..;,~':,f:"'r:': ');:':,)'~: ; , ' , . ..' ,:' ~ ' :d'r :.' ..:' ". ..' . . .' .' , ..' ':-, " . . . , '. . 1 :. ..' . .' ",' )\~U 1 :'"\),' ::'. ~'ft(t.lcl~t:fm ..~'n~.g~UJll!nted;: 'suty ~~ND afl{H1~NOi' gnlY 10~A '~~1~;~~~!:ail~h orowh 10YR.5/2. '. '~"'" ,~ , '.' ',<. ',< ,,::-d[y',: roose: This; unit appeans to tJ~ derlve~ 'off5~ta, fro~ th~,excayatror1.bt \,f1a:a~Jacsnt San'Drego', .< ~ -; ':';:,':~ Aq(Jeduct~ ,-" / N55E Note: Northwadt wan (T-1) fogged. b~twea~ Station No; 130 and 170 on Iv ~ : . . .", .J~~ _, '.' ',I " r ~ , I f1 : ~Jr of" ,.. . -l t. '. Qc ~ I Y~I.~;: '~u.,~~~rQ~.~ .~~IU~V!MfPi'rqu.119~;:, $1 LlY S~N.m';. ye'jlo~l~h ~ro'N,n c1a~;R :~{~, .df'J; loo.~ia;p~rous, :'..: . , I "I{. , fOcally abqriqarilt rQotl~t~ _an(~ rqot qaat$... Thlfl J4nit Ie d~rlVed Ir9m aJqReWash ,and w~qtharlng of . I ,. ~. . :',' . ,::,::, ./ the 'underlyIng ,ilrtificial fill' ;matarlals! .: . " ',',. ,.: :.',r .., ..,'". o!;. . " ' ' , ' ' ( ", ':- ' -, .. t ,.! , '. . . , , ,/' , . \ -:' .' . r. . ;i~'Q"b I ~{<;;';~yat~rhar~:'~~;i'(iYlql11nOP86lft ;;~fi> ~~riiouf$lt~'8A;N6, br~wJJi'ci~~a1~~~ty to da~f;T. "'bdse.". ',' ::' . . '. '.\''''': ", .":' . '. <;', ", , .' , , " . '.:, . , . .', .'.': t~m~d'um. d~n6e; pOrQU6,~.~\O~~Y aftgu\'lr.lSt!u!?tl;.t~eflQea.\."";~t:>~p~~n~!~,~~)let6. ~nd.root ~a$t6, .i . . ,,'!\ . :'. , .' ,'. ,; :.'-: 'cica II y ab u n c&J a m t ~ lot U fpatl (Q n /0 pen i;) u rrQ '!Va ~n d ,R'r~t Qi~rrta/,~,-; :!'~0!V": ~;.~';'l;b'.,;,;;, ',c. '. .' .. .: . . , '. <i~'o;" , ': ,,>.'. :-- . i.'..'...' ,:. . , . '~ :' , ". -' , ' ,,: , ,<" · /):':," :;'-:~.);'.:;.>';;r.,.;~~: .;Dt>'.. .:,": .', .'. . . . '. . .,,:' J': ": ..' Q 08 I ~.'. ;'.;':;;., gu~terri~ry ~(ItL!\(lurm SILTY SANa and ClJ\yegy SANfJdijrd~~~;1~~ij~AttO~ark 'graylsh brown. .' .', ,:'.'.,. ':;.,': T()YFl4J2to:'d;~k..yel/oWi8h brawn 10YA qia, da~p row~t/:ijt,~rijt1:R~iHc~~ to: 'g~m$e:, Unit i$ .' "'-/~ · i:" "" .' ", . '-' ,', ~ ~re~iomln~t~ly oQmpoee<j' ~f ma$'~iv$ly beda~p' silty ~nd' ~laYf1Y,:~~tt'~~J<<rnj:~.~'~y~y: ~lIt$~ .Conta~ta :.,' : {' , . ...: '. ' :. between mas5i"'~ly. badded portions of the' uriltara dl$,diate:;af1a:l~f~~itl~.Hal. ,'. :" i.,.' ..... '., .;. -.' .' ~ . ,> - . > .. : . . ' ,I . ' '. , ,- , :" .:' ,~~, ::";t ~~r. ~;~/~,~t':;6.;i:!'~:'-' ,.,':::... ,;:~: I I i')'f: ;;j:,h.:', \~r'::'.i} " - , l,' . ," · . , " . . :i<;'r::F"-: ),:{:'.:"( >>;-'{' >>-""";:,<'i ' ,; "L:" i~th~;}f;>i,,,\r' ;.r: " [:.,:.:,/:< . . ";. :::: . . ':;.. · .' . ",' .' ~ :. .' ..... ,'.' , . . .' ~ . .' ': ";', .j,;..:: c";:;';':"" ?:~' . ::f::f} ~~i~' ) .' >,; ;;::\'. .. .\':i.,b:?1}~~~~!['~rii~i!:;" . ,. ; ....,:::;Qp~- ";'; ;.;;,?i!, gYiltern~rY p~yfjq;;fiorul~Jfon;:8AN08rONei . euiT8t~'NEi~tli~~f'~'~'Yef~N(;1~ ;O'ar~:j'm~yf6~:'-,. '; :~;i:$..~t~~:~~:~~~:~ ~~'~" . ../.\ . ::. ~:'.> .\:;: Of, the WHdomalt faUlt. , Oontact~ . between' th~ dark ~~~HISht~c:() f~r~(;f~Jlaaa"~ oHl1fa U nit! (~'P :antl.. :'. '. , , . '.':;...:,; .i: .;::}: Qp1lara abrupt. other contacts Within the unit are gradational: . ii' ,:;".:., " :, . . . ":" · :', . :.' .' .' t, ,::,,: ;' >..:. , '. ; ,'. '.. , '. . '. : '.:. E' .~:::~ Y.:i~:.;'.. ':':. . . ... ..... '. . j .:.... '''QP'1'~ .;!.>:. ~~~ter~~~~I~'~ft,~grm~t,on; sANO~rrQNe!~'~ILj&1~~~~rf\~d~~~~t~N~.i wh~ta 1o~f{~:iJh '; .,", .' .'; . '. .' , \.: ,: ."~ to light., bFoWMllsh. gtay 1 OVA. 6/2, .qamp, dense: .tQq~JIY,:. i!lijJ.rrlfJ;a~~~."~~maQnW1tlE.lt"$ .&3tag~JI:. .!. . .' . .' ': .: . ". "~ ;.: :'. parbonate enr!~he~ ~alaoaola were.: florad., Gatoonate~wU~l.~!t~r'i$~!~~~Q,1 fQ.r'fft if. ~a.~Wn~f~~ ',', . , ; . . , , , ", ';' ", ", ~~:". ; ",. b'ock~ ps(i rfJefB& wht~t1 afferv~ea". VigorOUSlY With ap~Hq~tfQfJ tP'1~ ~~flR';~Qrdlo $ofutlon,., , ~ f " '. .... .,," : ,': ',.. ,., , .' '. '.: '. : ". . .'.:. :.,'dj:;~d:::t~;.~f ,,;t: , ;t '. .';; . .. ., , < ";"'~;'\'i.r.:~~,~r;:",, :::(,,~ ,.'"k,::,' J, , ", .l ",,:, ..tl.,;: ,; '"" . ('<i,' ~ '. ,,,.,, ,. ,~., c ,I ,;""""",,"'hj.i~d" \,,,i;;k.,.,. ,.,':'.':::'.,,',.:,.:,;< .,".,.) ","", bit, ," ./).,...;;.... "~"~~' I, ". ,: ,'- " , V"..:, , ..~.., "'1'1'; " . ,,;;'\~:;;._, ',; !',i",;"(~:",,,,:,,;;,\ ',,:, I,., Q!...... ,:t,. "/,j,;',,.;;~.,, i<l'~)~, ;",'iJ < :i.. , ].C. .Iii:,::, / ":1':;,,, .' ,."h ,;, ; ;i);i"'U'!:iJ;V;,~~~,j5/;f,}~'i.;J'i~j;ij " J':'~',,",i', ,<>i, I ii.'ll/"i'.. '.. i:~"H'~Aj'\fl:.\ii., ~f!,/L:j,;t')1f/t,)L,;~\'f~h~;;'{ ;, ,,"r,\ \.;'rj"IJ~;\j:::#. t ,; ilrii:),;~',\,,'~q:tl'),-:i:"'\' <'h\,I!' " l}:;;,",;';j}iltk+\d&;i,,~;~k{~'i~Nt~;'(, .... .....'.. ,;~ .oj '.:.', ,.. ,;/ '" ''': .".; .. - ,'," {) .QJ> i ~ " , 1 ,i/Vl ;.1 ~'. .:. "',".. ',." ~. ;. I l' '-:~: ~ ~ I, .. r ; I .... . ( ~ ~ : ; i J1"3:: -'o':!~'; '. ':.. Fm' ::-.' .'\,. " i( ",' . ~ I . ,I I ~ /.] ~, . i II ~ I, V .. ," . , . I ." ..:,-.1 ~ ". ' I - . ..'.:. . ,/ - :. ',' .I ~ " ;,' ';.'cb"'~ ',:')," ':,:' 'ft': '.. ,,'., ;; IV' --', ': t .S.yATION':NIlMfi~R;'" ". . " , " f' \ " .'. ~ , ~' \ .':,.,. , 1 . , : '''.;:~:'!;;~ : 'A I'" ,,% :,'. " ~' . '" .:. . r )- :. ,,' "~:'.. ." :;:.~;/: ~} ., .... :-;;:,1 ... , , . , v ; ~ " , .' _ ':;t;. _ " , '.' .. · , ,I ,'{",~<;:; .},<"":~' ':;::},' .~;,. ~'.t':' " ..,~:',..:)~r;,,:.,,~,::,)i'''' '.. '.'':' .." . , , " 1d9:0"" ,,c,,;;;.... "r":(~' .~ --2 ;,~;'> ;.'.' " .. ,;:~ r: ",( )~;:;j :,::~/,);~~:' \:, . X'" ~>. ~:' ,;>i'"~';' <;!, ';" ," ", ? p .;' . .' 'j e,~' - 1nae' ,)~ ~ ~E. · v- 'A, T: . '. , ........ ,1080': a '. N": . :J('f~'~) :. f> M" A' T' C H L I N' t: ,.. ", ----- p ",. (I . Q o - - 1075 I. : -<,. ' . .. I ." \ . " :..' .' '.. <"'" . '.c . I ;;, : " .,.: -. ~ : ';". .,..' , ,~' '. :.~ \;/...: ,'.t:~t:; , . .{ ,,:~;.'" '" ..., ",....( ~~ 'iI~~",~"4.'1 ,< ,,' :':. " .' '':.'; f " : .::.<~ . .. 10:; : . ,,/;V,j , ..::~,'~ , . ,";~ , I . , , "~, Ir>:(~ ..', ~;.< ~, >1' [:-' ",. . ,11.4' , .: ~; .' :... ? ; ;, ~: ' t " ". .. " .,.. 'j'. '... , , : ',.. ,. "\ ' " '. ':;; ';' .: , ~' ,~~ " " . . ';;..'.,;. :. >,:.", ;';'{ >( , . ~ ^ . /" .>. -'<, , '. '. . '; , " " i ;.i" " ",. .~. "/ . ~ ",,' ;,. - . ,,' -; ".: ... ) , , , , 'j. . : ,,-- I' : '. · ~ -t :ir ~:\:':<::, ". " ,'_ , '",' '.' .' , ~,_ . '.",:, "'::. ;', ."j;;:, " ,. f ;~'. :.':: .' \:; f, ~,',_:,,'i~~:7;:::: " " . 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Q,f~I'I:' v mg,,,,', ,\ii'liii~ ,~'I::~:;:,i;l; i '.~ i:.J.J. i[~2i ,1He " , dl'.">t.::.L,.....(~'i:/>4):q; ,~i!:./<.;;"\r]'1"~':-,,,1 ':';.' ,,~(.i;!:;.f::':~;!~..;,~, {ffdr;......(iit;~;..\:r; /,~,,,~-;'1,1 ',' I l~i:~.<~'lfi&dAj).~\'fft ~i~I,(;/..:~, · :; '.. :'i;i .; " ".. > . ,;';. ,'.,; ,".~:~?:,;" .::' ;.";,c" .;: " \;'.< ,: :":'7; / {.] fr':~,~; ; ,:' t,;'(f~lej'% ii:ji~ 116. ft . : . : ''''i' :" . '. . T If '. 'Ntlil!il{:'" e:~'ft?~~;fifj;{)a'.f.~;:,r,,: -' ~ t{;P:'~ i};:;~ ';'lff~ :,;"'l ~"''''i!Mj;'H~ {;tJ:...t\l;~";~t.~~i;:iih~~~'ti> ~~i;i111!:"'i!"tjr'J lii": .' ~;!#,. "IIH~;\i~' .("Jltflllf,1 )!l' :c . " f,- ,";(L', :, ':\/ ~: ;.t' )~"a~/;!'1\.' r :I')':;'))"~/\-f!i''1I~''l~~DI''~;J; >'~I;".':~:';' '~:l;'t~l"l?~ /, , . i;~'ll:'~~'ij:;>';';\i..:t~i.'~~~ ;>~~: 1I~1r.;f'..,~~:, '7'!i~~" .fj.~I2~- .,' ,".;..:,":',"',- ,I,~~+', e' 4~~ ,,' '. W .f~ ~ :rr ;:1 t {~~';." ~/~~~::.~ii f'~'; fN.' -~J~ '~~>~~f~3K' fI .Ff"\~~;f'~jlf<i ,ll!.~ . , ~~~ .,' < c,t\i ~~, y tll J",!Sl ,V( .\'(#.!.[~\~r Ir;~W;;\, , . i f1\,o/: .' }~"" '" t ~ ,', , ~~ 't.'/I.1-' ," ;:; -:; ';'. . '::' " .' ,'. ~ ;". , . '. · '~.1;A' tJ: ::::; ; '. :; ') <" <U:: ,/71" ,::}, :..: :;;; i: ,;:Y:i~:!l:~i .l . '10~5 -- ~ .' , '1Q70 ~ I ~; ~3Q' I ~'20' I ' ~10 I , Qeol I ;. , A . ,0 . ,- Qoal r) o · 6 , , () ~ rI (;) b " T~2, STATION NUMBER' 110 1070 ---- :~'e.~ 1065 --- , . '~L . '.j::a ....v ;.A " T. . I:': 1060--- ':Q N' . (f t ..) '. 1055--- 1050 ~ M A T C. H ~L I.. N' E 0'" I 10 I .20, I " I, 40 I c) J , , Flowe~f struetute' .. t o . I '? f/ '" f7 6 Fault Trend, N6.1W 1Z0 I 130. I 140 I o Qoal .rJ ~ 0001 , I . b p tj IJ (/ Q () ". ~ rl , ,', b . . " . p " 11 tJ I I': t/ , N50E ~ 150 I '160. I 110 l . . 'S0UT.HE,AST WALL b , <> # OcOI Q .~ ......" . .. 'f) c7 (i e:> o (l Q Ooal tI Q '<1 t1 . I T-2 STATION NUMBER 3t 1080 ~ , f) . ,) e L.' ~, 107$,- A' T\ I 0: NC (ft.) \) tI ~ Qp .. r1 '10'66 , ...... CJ N50E '> 20 I 10 I o. I Flower. struoture', , . , /) \~ '. P(I . . . ': ~ \ '50 I (.~ a"9' I " I 70 I 60:'! I ' \, , , Q .. . o \.> 'J' ,.0 (.I . " .' · rJ p'- '* , ~, p t? b ; . . tJ / l> .. , '" ,/' : Ocol () q I' " . . :7 . .. . " 11 Qp I ~" ~d 1/ 7 o' , r.1 , /;1 "t> f1 ,"> ~ tJ . ~ b 'p t> , ' . .' 17 '180 I -220. I 21.0 I 190 '1 it . " . 4> '~.10'56 '. I , () p. o o " o () "' C> 0001 ;;, 6 " . p ~ E L . .'", , ,IE :. --- ~06,O .V~ A' T I . o . - 1o~i5 N (ft.) tJ Qoal. 6 o t) ........ 1(j~O'" -10 I -20 I T-2 -30 STATION NUMBER I (# E L - 1080 ~ A' T, . I ' o ~ 1f,>75N . (ft.) ---- 1085 p . i (1 0001. o . . .. 0 II o Ooal t) f/ (1 , I) ~ , Qp () (I, ", t1 ~ 1010 \ .