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HomeMy WebLinkAboutTract Map 9833-2 Lot 29 Soil Report I I I I I I I I I I I I I I I I I I I RECEIVED APR 7 1999 CITY OF TEMECULA ENGINEERING DEPARTMENT SOIL AND FOUNDATION INVESTIGATION REPORT LOT 29 OF TRACT NO. 9833-2 A.P.N. 945-030-007 31422 JEDEDIAH SMITH ROAD CITY OF TEMECULA CALIFORNIA FOR MER CONSTRUCTION C/O MR. MIKE REGUS PROJECT NO. 99-006.PI DATED APRIL 5. 1999 Lakeshore Engineering \ I I I I I I I I I I I I I I I I I I i I LAKESHORE Engineering Consulting Civil Engineering and Geologists April 5, 1999 Project No: 99-006.PI Client: Mr. Mike Regus C/O MER Construction 21841 Kiowe Lane Huntington Beach, CA 9646 (714) 963-0338 Subject: Soil and Foundation (Geotechnical) Report Proposed New Single Family Residence Lot 29 of Tract No. 9833-2 City of Temecula, CA. A.P.N. 945-030-007 INTRODUCTION This report presents our findings and conclusions of a soil and foundation investigation for the proposed development of a new single family residence to be located at the subject site. The purpose of this investigation was to 1) evaluate the foundation and subsurface soil conditions at the site, and 2) provide pertinent foundation recommendations for proposed development. This investigation included the following scope of work: 1) Performed four exploratory trenches within the proposed building pad and driveway areas to determine subsurface conditions and recover soil samples for laboratory testing (Appendix A). 2) Laboratory testing of a representative soil sample to determine the soil properties (Appendix B). 3) Engineering analyses for foundation and necessary earthwork preparation. 4) The preparation of this report. PROPOSED DEVELOPMENT The proposed building area is situated on the nose of a broad ridge, therefore grading is anticipated to truncate the ridge top to construct a level building pad. The proposed development will consist of a one and/or story, custom built, upper scaled, single family residence in the order of 3000 square of living space, founded on a level graded pad. Construction is expected to be of woodframed and stucco walls with tile roofing, supported on conventional spread footings. 31740-2 Railroad Canyon Road. Canyon Lake, CA 92587 . (909) 244-2913 . FAX: (909) 244-2987 z., I I I I I I I I I I I I I I I I I I I IN: 0990011.01 - Z o m )( ~ )> 11 ~ INDEX MAP OF MIKE REGUS PROPERTY LOT 29, TRACT 9833-2 31422 JEDEDfAH SMITH ROAD CITY OF TEMECULA RIVERSIDE COUNTY CALIFORNIA :? BASE MAP: State of Califomia, Speclal Studies Zone Official Map 1980 on Base Map of USGS 7.5 min. Peachanga Quadrangle. 1973 FIGURE 1 I I I I il I I I I I I I I I I I I I I I April 5, 1999 Project No: 99-006.PI Page Two SITE DESCRIPTION The subject property is a flag lot, consisting of approximately 2.88 gross acres of undulating rolling hill country. Natural slopes on the site average about 4:1 (H:V), with 3:1 maximum pitch. Maximum relief between valley and ridge top onsite is about 50 feet. The property is at present unimproved, and supports annual local grass and scattered cacti clusters. No fills and/or debris were observed on the property. The surface contours in general is smooth and uniform with no boulder or rock outcrop noted. A drainage course, crosses the property along the easterly side, in a north-southerly direction. The general drainage appears to be by natural sheetflow towards the seasonal watercourse with exit at the southeasterly corner of the property. SUBSURFACE CONDITIONS Four exploratory backhoe pits were excavated on the site to determine the subsurface soil profile. Based on our exploratory efforts, the upper ridge areas are mantle with a thin layer of topsoil underlain by Pauba Formation of Sandstone and Siltstone seams. The topsoil consist of a thin layer of approximately 2 1/2 feet of a lighter brown, Silty SAND/Sandy SILT with trace of clay. In the low wash areas (proposed driveway crossing) the loose topsoil/colluvial soil section is thicker, at about 5 to 6 feet, consisting of grey-brown Sandy Silt and fine sand. Below 5 feet, the soil becomes dense and slightly cemented. pauba Sandstone is suspected to underlie this alluvial soil at lower depths (about 10 feet) . Generally, the upper topsoil is considered LOW in expansion potential. No water seepage, rocks and/or boulders were exposed in our exploratory trenches. REGIONAL GEOLOGY SETTING For regional geologic conditions, groundwater, faulting and seismicity and secondary effects, please refer to geology report prepared by Mr. JOhnathan L. Rossi, report dated March 29, 1999 (P.N. 09900ll.0l) attached in the appendix as part of this report. Lakeshore Engineering ~ ! I I I I I I I I I I I I I I I I I I I April 5, 1999 Project No: 99-006.PI Page Three CONCLUSION AND RECOMMENDATIONS GENERAL From a soil and foundation engineering standpoint, the site will be suitable for the proposed new single family residential construction, provided all conclusions and recommendations presented in this report are incorporated in the design considerations, project plans and specifications. GRADING AND EARTHWORK Based upon our review of grading plan already prepared for subject property (please see grading plan in pocket), it is our understanding that site grading will be required to provide: 1) a single level building pad; 2) suitable foundation conditions to support the proposed building structure; 3) adequate surface gradients for control of water runoff; and 4) excavation into native soils and/or compacted fills to accommodate the installation of foundation and utility systems. After the areas to be graded have been stripped and cleared of vegetation, the on-site soils will be considered satisfactory for reuse in the construction of on-site fills. Per review of grading plan prepared for the site, the nose of ridge top will be truncated/lowered an average of 10 feet, with proposed building footprint to be situated on the cut portion of the constructed pad. Sliver perimeter fill slopes are proposed to enlarge the cut pad. Manufactured fill slopes will be in the order of about 20 feet high with 8 to 10 feet of vertical fill and cut slope is also in the order of 20 high. All slopes will be pitched at 2:1 (H:V). The exposed cut building pad (after removal of 10+ feet of hill top) will likely expose competent, very dense to hard surface subgrade, considered suitable for support of proposed structure. Determination to overexcavate building pad to provide for a uniform foundation fill cushion blanket will be made by consultant based on field inspections at time of grading operation. In the area of the driveway wash crossing, the upper surface soils are loose and considered in its present condition, unsuitable for support of vehicle traffic. The upper 5 to 6 feet of topsoil or slopewash should be removed and reworked (moisture conditioned and recompacted) prior to concrete driveway paving. Actual depths of overexcavation should be field determined by geologist or engineer at the time of grading operations. In addition, Lakeshore Engineering recommends that the upper 18 inches of driveway subgrade in the watercourse crossing section be underlain by a rockbed (1 1/2 + inches diameter) to provide for an unyielding base layer. Lakeshore Engineering ~ I I I I I I I I I I I I I I I I I I I April 5, 1999 Project No: 99-006.PI Page Four All exposed bottom of grading excavation should first be scarified another 12 inches, moisture conditioned to near optimum and densified to at least 90 percent of the maximum laboratory dry density as determined by the A.S.T.M. D1557-78 compaction method. Boulders encountered during grading that are 6 inches in diameter or larger, should not be used in structural fills. If overexcavation of building pad is required, the limits of rework should extend at least 5 feet beyond the building footprints. Any surface or subsurface obstructions encountered during grading such as rocks, utility/irrigation lines should be removed .from any areas to receive fill. No underground obstructions nor facilities should remain in any structural areas which receive compacted fills, building foundations, concrete slabs and/or pavements. Depression and/or cavities (including exploratory trenches) created as a result of the grading obstruction removal, should be properly backfilled with suitable fill materials and compacted under engineering observation and testing. All fills should be densified in conformance with the appropriate grading code but shall be less than 90 percent relative compaction by mechanical means only. EXCAVATING AND RIPPABILITY Rework of on-site soils should not be difficult to accomplish with standard earthmoving equipment such as a D-6 or larger. The walls of temporary construction excavations should stand nearly vertical, provided the total depth does not exceed 5 feet and surficial stability is verified. Shoring of excavation walls or flattening may be required if greater excavation depths are necessary. For deeper cuts, slopes should not be made steeper than 1:1 (H:V). All work associated with trench shoring must conform to the State of California Safety Codes. Native organic free soils may be permitted provided both the backfill and the native materials have a m~n~mum sand equivalent of 30 and the required relative compaction can be achieved. GRADING CONTROL All grading and earthwork including trench backfill should be performed under the observation and testing of the soils consultant or their representative. Sufficient notification prior to stripping and earthwork construction is essential in order that the work be adequately observed and tested. In order for us to provide a written opinion as to the adequacy of the soil compaction and trench backfill, the entire operation, most importantly at the time of trench backfill, should be performed under our observation and testing. Lakeshore Engineering (p I I I I I I I I I I I I I I I I I I I April 5, 1999 Project No: 99-006.PI Page Five FOUNDATION DESIGN FOOTING The proposed single family residential development may be supported on conventional spread footings established in competent native subgrade or entirely on engineered (compacted) fills. These spread footings may be designed for an allowable bearing value of 1500 pounds per square foot. This deSign value may be increase by one third, if the Structural Engineer takes into consideration short duration structural loading conditions, such as induced by wind and/or seismic forces. Footings should be founded at least 18 inches below the lowest adjacent ground surface, for one and/or two story structures. All continuous foundations should be reinforced with at least two no. 4 rebars at top and two rebars at bottom (total of 4 rebars) and consistent with the recommendations of the Structural Engineer or Architect and the guidelines in the U.B.C. Reinforcement should also be placed across garage grade beam at door opening. SETTLEMENT Total settlement due to structural loads should not be a design factor as they should be less than 3/4 inch. Differential settlement should be within tolerable limits. LATERAL CAPACITY For design, resistance to lateral loads can be assumed to be provided by friction acting at the based of the foundations and by passive earth pressure and may be combine without reduction. If passive earth pressure is used, it is important that backfill should be placed under engineering observation and testing. A coefficient of friction of 0.30 may be used with the dead load forces. An allowable lateral passive earth pressure of 200 pounds per square foot per foot of depth may be used for the sides of footings poured against undisturbed and/or recompacted soils. The lateral bearing values indicated above are for the total of dead and frequently applied live loads. If the normal code requirements are used for seismic design, the values may be increased by 1/3 for short durations of the loading which include the effect of wind or seismic forces. RETAINING WALLS Per review of grading plan, no retaining walls are proposed at this time. Lakeshore Engineering \ I I I I I I I I I I I I I I I I I I I April 5, 1999 Project No: 99-006.PI Page Six SLOPE STABILITY Proposed cut and fill slopes are less than 30 feet in overall height and pitched at 2:1 (H:V). Slopes to be constructed as proposed considered grossly stable from deep seated failure. CONCRETE SLAB - ON - GRADE The onsite native and stockpile soils are granular in nature and considered to be low in expansion potential. Expansive soil potential should be reviewed at completion of rough grading operation. Concrete floor slabs may be supported directly on properly prepared subgrade. Presaturation of subgrade is not required. If a floor covering that could be critically affected by moisture, such as vinyl tile, slabs should be protected by a plastic vapor barrier of six-mil thickness. The sheet should be covered by at least two-inches of sand cushion to prevent punctures and aid in concrete cure. The concrete floor slabs should be reinforced with at least 6" x 6"-#10/#10 welded wire mesh or equivalent bar reinforcing ( no. 4 rebars at 24 inches on center) and installed at mid-height (using chair support). Concrete floor slabs should be at least 4 inches thick nominal. SITE DRAINAGE Positive drainage should be provided around the perimeter of all structures to minimize water infiltrating into the underlying soils. Finish subgrade adjacent to exterior footings should be sloped down and away to facilitate surface drainage. All drainage should be directed off-site via non-erosive devices (swales and ditches). The homeowner should be made aware of the potential problems which may develop when drainage is altered through construction of retaining walls, patios and pools. Ponding water, leaking irrigation systems, overwatering or other conditions which could lead to ground saturation must be avoided. FOOTING TRENCH EXCAVATION INSPECTION All footing excavations should be inspected and approved by the Soils Consultant prior to placement of footing forms, reinforcement, or concrete. Materials generated from excavations should not be spread on slab-on-grade areas, provided they are compacted and tested. Lakeshore Engineering ~ I I I I I I I I I I I I I I I I I I I April 5, 1999 Project No: 99-006.PI Page Seven GENERAL INFORMATION AND LIMITATIONS This report presents recommendations pertaining to the subject site based on the assumption that the subsurface conditions do not deviate appreciably from those disclosed by our exploratory trenches. In view of the general conditions of the area, the possibility of different local soil conditions cannot be discounted. It is the responsibility of the owner to bring any deviations or unexpected conditions observed during construction to the attention of the consulting engineer. In this way, any required supplemental recommendations can be made with a minimum of delay to the project. Prior to initiation of grading, a meeting should be arranged by the developer and should be attended by representatives of the governmental agencies, contractors, consultants and the developer. Construction should be inspected at the following stages by the Geotechnical Consultant. o Upon completion of demolition and clearing. o During all rough grading operations including removal of unstable materials, precompaction and filling operations. o During trench backfilling but prior to paving or other construction over backfill. o When any unusual conditions are encountered. The findings and recommendations of this report were prepared in accordance with generally accepted professional principles and practice in the field of geotechnical engineering. This warranty is in lieu of all other warranties, either express or implied. to be of service. If you have A - EXPLORATORY LOGS B - LAB. RESULTS GEOLOGIC REPORT BY JOHN L. ROSSI IN POCKET Lakeshore Engineering l2\ I I I I I I I I I I I I I I I I I I I APPENDIX t. FIELD EXPLORATION Field exploration was performed on the morning of April 5, 1999 using a backhoe (Jack Curtis Backhoe 909-674-6156). The soils were continuously logged by our field personnel and classified by visual examination in accordance with the Unified Soil Classification System. Our trench logs are attached for review. To evaluate the compaction characteristics of the fill material, field density tests were performed. Also, representative bulk samples were recovered and shipped to the laboratory in polythelene bags for laboratory testing. MER Construction/Mike Regus Lot 29 Tract 9833-2 Jedediah Smith Project No. 99-014.PI Dated April 5, 1999 Lakeshore Engineering \0 PLOT PLAN , ., , " , " ,la, ,. '('I., ','-J "" <,~ ...... ~n.o "I'( N ... , " - ~r). ........, \ \ .\ , , \ , \ .' t ". ,,'00' .,. ~~t.""\ \', ',- ... ~t'O) ... , ......__.../ " , '... . e.P'-. / j' " . .... -...." \ EXPLANATION IT -4 I APPROX. LOCOTION OF EXPLORATORY TRENCH. /"'11\.~ ~~~....... -1,0 "'i\4,~' ~\~ LAKESHORE Engineering SINGLE FAMILY RESIDENCE LOT 29 TRACT 9833-2 31422 JEDEDlAH SMITH RD. TEMECULA . CA. \\ CONSULTING CIVIL ENGINEERS Project No: 99-06.PI Dote 3/11/1999 Agure No: 2 I I I I ~ I I I I I I I I I I I I I I I TRENCH LOG Logged By: f' '/0 N (" . Date 4lS\c,c., . Equipment: L.l..UTI~ ~~ Thlllogil.reptll5enlationol,uburfacI,solllndgroundwalerconditiollflllhelimelllGplaceofexcavalion, with the passage of 11m. or Itlny other bcatlon there may be conuQuenliil changes In condttion5. Trench Number T-~ "' . Q) ~ u: .0 0_ " - >- c:l L..eC.:ATLD ~ : S,1O~ t)f'" !t\LLL) ~C;~ 'g/L,\1.4 S~ <>1<ml-CJ'l ~Icr. - ~~~ LT , . ,l2..ceT H AV>'t- J .J:::flv1A. j). p 01U) LA. S. . 10 81>mlOSTOrvlE.. , 31L.,~T~ KE1\Y\.\,<f.._ Fr2..vfle.~J ~ Hzt2.- ~ING, ~&E. '0 l-tAA.C" T~.plCJ\L flflvt.eA ~17oN 15 IOT.tL..- 4 ~4 Fl'. No ~L~lL CAvI~, N..o W"""E"L s-ee:~E ~ -r~ ~ 16A-c.ta'IL>l.t50. Logged By:, F.jDJ\} b Trench , Number Date 4{shi " . /) Equipment:~ _ fb8'S t:. TOf> 1- Z. TI'\ nl l.JtII{Erz..., '!SF &OO'6l\ Li. $iW $lt...1I1 ~s.J Dttw.P-J)~~... RA~:;I\-\AtL. )~~(A,L- f..ue,~ ~lJ~ Q,A-.:){)&iOf'\,E / ~P.>~ g~rOflE, ~I T~ ~1L:\.!\ t..LA'iS. .8GD~ 1D1A'L- ~T-\.\ '5 FT. tv D t..MvNc' DF- SltsEvLl'IQ LL 1\9D J-hD 6~D ~. !?,Ad::-.rlLL..E; D. 20 Surface Elevation: Trench Orientation~ flurr PG&\N Trench Dimensions:2W' U)X ~/ !) X S' Groundwater Depth: ~~. 10 15 20 LAKESHORE Engineering CONSULTING ENGINEERS AND GEOLOGIST SINGLE FAMILY RESIDENCE LOT 29 TRACT 9833-2 31422 JEDEDIAH SMITH RD. TEMECULA , CA. Fig. No. 3 ~ PROJ. NO. 99-06.PI I I Surface Elevation: Logged By: F,.:::jl)l'qC:,. Trench Orientatio~ \)llST V'LAN. Date.:::! I'S 1'11- . Trench Dimensions24'ltA (,'''X "." Equipment: ClAl2.."T~ ~HoE-. x 'U..J '- L . Thlllog II I r.pttlerCation olwb5urtiCI, ICIR andgtOuna<<iiler conditio,. It the time and place 01 exeiViItion. I Groundwater Depth: MD~ - .."h.'....'..,"'.""."''''''''''''Ioo'''''.'''''''''''....".,,,,..,'''.'''"',,,,.. <..~'<-";~ ~ Ql ~ ,-;- _~<s" ",<<> ",03- <-. I '" >~ ".", <;,'<;fi>. ~ .0 0_ ~.:S'<;,'<' ~ '1,\ m~ro ,~"'..~v I I I I I I I I I I I I I I I TRENCH LOG Trench Number T-3 5 10 15 20 Surface Elevation: Trench Orientation~-Pl oT fL:irN Trench Dimensions2l!h<::ixE'-D)( \2Yz. Groundwater Depth: N 5 10 1SJ ~ 120, ..s.a:u,. It - IN ~H- . lol>SC,IL'-' t:iUi'l ~~- Skrr4C'is..ILi/S\Lr-l " ~,I,/ett..'l F\ Nlz... a t2.A FN J L1'r-.~ /W)1~"/Rcxs1' tt~, 6i1&.lL'f 1'~('M60 &sC.m~ 2:>~~ Sfl*].~ L.l:I!J.~ TrzMjE, DNGi ~ Al.LI..\.\JIU u-- -rn7~ D&Th b FT. ~D g~ ltt..L. CJ~"'hN6 ND lAm"1~ .31:::e.P~E- 6~~. itl..B'\\Ct,,4 ~1ll.E.~. Logged By: ; , 5A-lME:. ~m.c\J~ Tre nc h Number Date Equipment: 1...bG: X - DellJE:... . T-4 "'Th~t\IL/ilu.\.l\JluM - (,,'t2Jr.(u;.\l .&11DlAN, I ~e... ~IGf ~m , -fC'eO~ " MClt::.T ':>LDPEWre.16- ("'1It.E.. SILT\{ ~'R (b~ I rJ" Ii2flrlT\>'f A ve--~ -r S-' ~.L'>..vtJ:a DEw-~€::, l64=-\R~ ~~~ - LL:A'I ~/LT SaMt F l1Llot..L. ~ L. u..un ~ T)' LGw19ST~' U~. /lJA11 t?~ . 1'D'Li9:rL- 'B'E;-P 1i.1t- g r \' . t<l 'D ~A: LL- L..A v I i'C ~ f\J !:I ~"\'E;:YL.. s;;;. 6e:~ \"~ €:';f\O::.Pl U E;D. LAKESHORE Engineering CONSULTING ENGINEERS AND GEOLOGIST SINGLE FAMILY RESIDENCE LOT 29 TRACT 9833-2 31422 JEDEDIAH SMITH RD. TEMECULA , CA. Fig. No. 3A. ~ PROJ. NO. 99-06.PI I I I I I II I I I I I I I I ,I I I I I APPENDIX B LABORATORY TESTING EXPANSION INDEX TEST A representative soil sample was collected in the field and tested in the laboratory in accordance with the A.S.C.E. Expansion Index Test Method as specified by U.B.C. The degree of expansion potential was evaluated from.measured soil volume changes obtained during soil moisture alterations. The results of the test are presented below: Trench Depth Soil Expansion Expansion No. (Ft. ) Description Index Potential ------ ----- ----------- --------- --------- T-l 0-2 Silty SAND < 20 LOW (SM/SP) MER Construction/Mike Regus Lot 29 Tract 9833-2 Jedediah Smith Project No. 99-0l4.PI Dated April 5, 1999 \Lit Lakeshore Engineering I I I I I I I I I I I I I I I I I I I JONATHAN L. ROSSI CONSULTING GEOLOGIST REGIONAL GEOLOGIC CONDITIONS AT THE REGUS PROPERTY 31422 JEDEDIAH SMITH ROAD TEMECULAlRANCHO CALIFORNIA AREA RIVERSIDE COUNTY CALIFORNIA PROJECT NO. 0990011.01 PREPARED FOR: LAKESHORE ENGINEERING 31606 Railroad Canyon Road #101 Canyon Lakes, California 92587 PREPARED BY: JONATHAN L. ROSSI, CONSULTING GEOLOGIST P.O. Box 4018, Big Bear Lake California 92315 March 29, 1999 \-6 P.O. BOX 4018, BIG BEAR LAKE, CALIFORNIA 92315. I i I I I I I I I I I I I I I I I I I IN: 0990011.01 TABLE OF CONTENTS Page 1.0 INTRODUCTION 1.0 2.0 SUMMARY OF FINDINGS 2.1 Geologic Setting 2.2 On-Site Geology - Earth Materials - 2.2.1 Topsoil 2.2.2 Quaternary Alluvium 2.2.3 Bedrock - Pauba Formation 3.0 3.0 5.0 5.0 5.0 5.0 3.0 GROUNDWATER 6.0 4.0 FAULTING AND SEISMICITY 4.1 Faulting 4.2 Seismicity 4.3 Secondary Seismic Effects 6.0 6.0 8.0 10.0 5.0 CONCLUSIONS & RECOMMENDATIONS 5.1 Conclusions 5.2 Recommendations 10.0 10.0 11.0 6.0 LIMITATIONS STATEMENT 12.0 ACCOMPANYING MAPS. TABLES. PLATES AND APPENDICES Fiaures - Figure 1 - Index Map (EQ Fault Map; 2000 sc.)------------------------------------------------------ 2.0 Figure 2 -- Site Plan & Geologic Map (photoreduction) ------------------------------------------- 4.0 Figure 3 - Regional Fault & Seismicity Map ------------------------------------------------------------ 7.0 Tables - Table I - Regional Active Faulting ____________m___________________________________________--------------- 8.0 Table 11- Maximum Credible EQ., Maximum Ground Acceleration _____________________m_______ 9.0 ADDendices - Appendix - References ii \10 IJONATHAN L. ROSSI,CONSULTING GEOLOGIST. P.O. BOX 4018,BIG BEARLAKE,CALlFORNIA 92315. I I I I I I I I I I I I I I I I I I I JONATHAN L. ROSSI CONSULTING GEOLOGIST March 29, 1999 IN: 0990011.01 TO: Lakeshore Engineering 31740-2 Railroad Canyon Rd. Canyon Lakes, Ca. 92587 SUBJECT: REPORT - Geologic Conditions at the Site of Proposed Residential Structure, Regus Property, Located on the North Side of Jedediah Smith Rd., East of Pescado Dr., in the Rancho CaliforniafTemecula Area, Riverside County, California.(E 1/2. NW1/4, Sec 17, TBS, R2W, SBB&M). ATTENTION: Fen Yong, RCE - Principal, Lakeshore Engineering Mike Regus - Owner 1.0 INTRODUCTION- We are pleased to present this letter report of findings for the existing geologic conditions at the proposed residential development located on the north side of Jedediah Smith Road, East Temecula/Rancho California area, Riverside County, California. The proposed site consists of a graded cut/fill lot facing Jedediah Smith Road. A small south facing cut slope is located at the north side of the lot. A graded driveway provides access to the site. Roads are paved with curb and gutter in places. Our scope of work is limited to providing a description of the geologic conditions present at the subject site including general geology, faulting and seismicity, groundwater description, and presentation in this letter report. Seismic conditions were evaluated based on published earthquake and seismic information. Our scope of work does not address or consider any aspects of a Phase I Site Assessment for Hazardous Materials or Asbestos containing building materials, and is not a soils & foundation investigation, but provides geologic interpretation of site conditions for the soils engineer and the geotechnical report. This letter report presents our findings, conclusions, and recommendations concerning the existing geologic and earthquake/seismic conditions present at the subject site. Our work is provided to the soils engineer for further geotechnical evaluation. A Precise Grading Plan prepared by Lakeshore Engineering dated February 5, 1999 was used to review the proposed grading, and topography. The site was visited on Monday, March 29. 1999. -1- \'\ P.O. BOX 4018, BIG BEAR LAKE, CALIFORNIA 92315. I I I I I I I I I I I I I I I I I I I IN: 0990011.0l - Z o m )( ~ )> 11 ~ INDEX MAP OF MIKE REGUS PROPERTY LOT 29, TRACT 9833-2 31422 JEDEDIAH SMITH ROAD CITY OF TEMECULA RIVERSIDE COUNTY CALIFORNIA 'vro BASE MAP: State of California, Special Studies Zone Official Map 1980 nn R.......l..........I 11~"'~"7 It!. _,_ "'__~L ___ __ -. . . . ~__ FIGURE 1 I I I I I I I I I I I I I I I I I I -3- March 29, 1999 IN: 0990011.01 2.0 SUMMARY of FINDINGS - 2.1 GEOLOGIC SETTING - The subject site is situated at the southwestern margin of an elevated older alluvial plain forming a pediment surface of rolling foothills north and east of the Temecula Valley, and north of the Pauba Valley. The older alluvium in this area consists primarily of a massive, partially cemented, well-indurated Pleistocene sandstone (Pabua Formation-Sandstone unit) exposed across most of the region. The Pauba Formation contains a massive to poorly bedded, reddish brown, coarse to graded sandstone unit, in places containing thin (6" to 12") interbeds of grey green to grey brown micaceous siltstone. Siltstone can be predominant in a portion of the section with minor sandstone. In the south Temecula Valley and Pauba Valley the older Pleistocene/Pliocene Temecula Arkose underlies the Pauba Sandstone. The Temecula Arkose consists of a thick section of layered very fine sandstone to siltstone. Narrow, thin deposits of younger alluvium are present within the erosional canyons developed within the pediment surface. The older alluvial pediment surface is bordered on the north and east by intrusive granitic and older marine metasediments of Bachelor Mtn. and Black Hills. Traces of the Agua Caliente Fault zone are mapped (CDMG Santa Ana Sheet-1965) at the contact of the Pauba sandstone with these hard rock units. The Wildomar Fault on the northeast, and the Willard Fault on the southwest border the TemeculalElsinore Graben. Both of these fault segments are considered part of greater Whittier/Elsinore Fault Zone. The Pabua sandstone pediment surface is located within the boundaries of the Perris structural block. The Perris Block is a northwest-southeast trending structural block bordered on the northeast by the San Jacinto fault, on the southwest by the Whittier/Elsinore Fault System (Wildomar Fault), on the northwest by the Chino Basin, and on the southeast by the Agua Calenti fault Zone and Boreggo Valley. The Santa Ana Mountains Block lies to the southwest of the Perris Block. The closest active or potentially actiye faults capable of effecting the subject site (if an earthquake event were to occur on one of these faults near the site) are the Wildomar Fault approximately 1/2 mile to the southwest, and the San Jacinto Fault approximately 21.0 miles to the northeast. Both of these faults are considered active, and are Earthquake Fault Zones. The recently zoned Wolf Valley fault located some 1.75 miles to the south-southwest. This is on the southwest side of the Temecula Graben. The Wolf Valley Fault is considered a portion of the Elsinore Fault Zone, and possibly an extension of the Willard Fault further to the northeast, on the southwest side of the Temecula Valley. No active or potentially active faults were observed on the subject property, or were present on the site in the literature reviewed. The site is not included within the Wildomar Fault Earthquake Fault Zone. Other fault features or linear fault like features are reported on M.P. Kennedy's Map (CDMG Sp.Rpt. 131, Plate 1) within the Pauba Plain to the north and east of the site. These features are not Earthquake Fault Zones, and are not well defined in the literature. The original and the second MWD San Diego Aqueducts (oriented N-S) are located 1/4 mile to the west. \l\ IJONATHAN L. ROSSI,CONSULTING GEOLOGIST. P.O. BOX 4018,BIG BEARLAKE,CALlFORNIA 92315 . :1;~-~ '. " \~~~~.:-. ". ~~ i l F ~jl!il: · Ill! ._ ,.' IL'I!I!'ll'!i !:1!!!::1 :11,'11 . l"ll!"li II illl .ii1If!!i II'il!' iililli" !'!II~! l?ilii1il '!I ':1 . i u:: s ~;~I!ll'll !Il'l&! Il,II' I! -Iii' 11;!I,',i:,,:,'I!ill .1"" hi.. -', . '!" ;i' I". "!"II ! j' II Ii""; i.. I I I I I I I I I I I / , , , , .' .",. I~- : ~,o". ,~.~ ~~/'''~, .:ot .~ ~ 52 -I m -a r- > :z: . ~, t I , I , , ", " .. J;i9&o.m'l ~ .Pl:SI~$,~~ _' II Ni~'i" >i.".iSS>"I,l ~ r ,..!li", i !Wi!id '\ ~l ;id!~ '; , . ~~i!'! :\~8 ~ 'it- :; ! tl. r~ \ . ~I 'll"! ' \ ~Hjj i I, '.I if i i i f ' ~ , , , , I \ \ ,. " " , , , . s " , :~ o i f i , , ~ ~ IH .i..i.~ If \; " ,~ , , t- 10 , I , 0 " ~ ....-..."i!' , , r~5 ~ hI ! A" , I ~ ........ J I ~ '8 RJ.i ii,\~: . 1 1)____ ....' "Q'\ J " \ , " c. , i8 !" i J I ;i ~ I l: i I B _ l , ~ z . "1"1- , _1 rbO:' ~ .' !U ~!!1 ~'rIl , i ~ ~f j i i i, j , t ; , !- l i f I g. ee- 'fvrrr fill" ! I; ii, I ~i !HI ! , i , I I , I ; o I~ . r! I' ! ~ ! , f " i ~ ~! :. , r I . i"111 i , ~ ~ ltl ;J: o .-I o fll t:l c:: (') .-I o Z d? I I I I ~ o l! =< . ~ . ~, .. ;. !!J I o j ! ~ ! i llll; o oi i il n 'ld! Inn liiH i ii . J i iii nann i a i ~ 'I " !n i .. I ~ nn Ii,! j .. i ; I i ! . 8 . ! i I ~ II Ii , !I i ~l ! i II. I.!! idil ~: ! ~= mill if!11 i mSiI lWi ",s gEl. lill i ! , , , ! ! , I I I i ! II ,. f I I I I g ~ i!J 11 ~ 1)1 . 'I flU 'lji( f!ffji j !Ii! h, 1! iff .1 f Hlf!!r fIlii'! . I,ll ;11 !. f~I I' I .,'1 If' I . ! frhiU J I: I, r J.t. " I II r .1Itll! 1: I J lj"f' 'I i . f.' ~ PI 11 I :f I . . , i jjl ljji Ii 1m w 11lfi I fill ,ltf li fill ,".! ilif'd 'III 111'1'11..1 I I, 14 "Illf.I, WI..r ! llil.:1 flrli!! lIlt Jfl"I. ! , 'I II: " ,II' rllf I'll! I l I. I. hi I 'II, r.hl1l' 'I ".t' ,. I,.' r "I I I h f !If Ii, If! ' JI .1,. I 'I 'I il,' I ;". t fl. i.. !J I r , , Hi' III 'Ii !i! IJ' II! ill IJ' d 11'; III HI! ~il ,.fl If! "I H., I 1 .. Hit If lI'iff 'Ii, '. I .,' .r. II .. II .1 .. , , 'I !11'1!' I..., I 'I !' HII' II ."..IJ :i l!i!H~ -. :'lIII,1 f.f f . I, I 1;li1. I IIJI'" . I I I If"fr I II!I-' ~. :::f . . . '11/1" , iIH ,if Illlll, h'; !l , , Ig I' . gll. f! WI,il'l ." .1 Ilfl . I lit' ! II., II. Ill! .. , l-J H~3 t'9"1o~ i;:i2~ fEH~ "'.:",,~ Jim 1m qii c .., ... ... " "' n ? " J , i . . . ~ . ~ ., ~~~ :.~~ !:iliC) 2~~ ~a= ~!~ ~~~ ~ . ~ ~ I . ." as c:: ::= m I\) I I I I I I I I I I I I I I I I I I -5- March 29, 1999 IN: 0990011.01 2.2 ON-SITE GEOLOGY - EARTH MATERIALS- 2.2.1 TODsoil- A thin layer of poorly developed topsoil is usually present over native subsoil and bedrock. Topsoil in the area consist of loose, brown to reddish brown, porous, well graded silty sands and clayey sands where shallow bedrock is present (Pauba Fm. sandstone). There were no. exploratory trenches excavated during the course of this study. Natural soil profiles are exposed in existing cut slopes in the surrounding area, and in nearby road cuts. 2.2.2 Alluvium 10all- A thick (several feet), porous, topsoil section is typical over sandy alluvial and colluvial soil deposits seen in the central stream channel shown on Figure 2. Unconsolidated soils are typically loose to medium dense, easily excavated, poorly graded fine to medium sand, sandy silts, and gravelly sands. Pauba Sandstone bedrock is suspected to underlie the alluyial soils. Pauba Sandstone is mapped across the local area (CDMG SpRpt. 131), and is mapped at the site. 2.2.3 Bedrock 10Dssl- Bedrock was not exposed on the site, but is seen on the adjacent property to the east, and is mapped (CDMG 131) underlying the property. Bedrock consists of the Quaternary Pauba Formation Sandstone, a regionally distributed poorly cemented (CaC03 & salts), friable well graded sandstone with limited poorly defined bedding, and containing interbeds of grey to brown siltstone. The Pauba is a young continental deposit containing a large number of sedimentary depositional structures: coarse channel fills, cross-bedding and graded bedding, and alluvial fan structures. Pauba sandstone at the subject site consists of reddish brown to brown well graded sandstone with a moderately high silt and clay content. In addition to salt cementation clay acts to bind the sand grains of the arkosic sediment into poorly consolidated continental sandstone. Excayation is relatively easy with standard backhoe, and the Pauba stands up well in cut slopes up to 30 feet. However, the Pauba is easily eroded, and can be cut with water where run-off is not controlled. Erosional gullying and animal burrowing in the slope face is considered a problem with existing slopes in the area. Bedrock is not exposed at the surface at the subject site, however is present some 3 to 5 feet below the existing grade. The Temecula Arkose is thought to underlie the Pauba Sandstone at the subject site, howeyer the Temecula Arkose is not exposed in the site vicinity. 7,.\ I JONATHAN L. ROSSI,CONSULTING GEOLOGIST. P.O. BOX 4018,BIG BEARLAKE,CALlFORNIA 92315 . II II I I I I I I I I I I II I I I I I -6- March 29, 1999 IN: 0990011.01 3.0 GROUNDWATER- Groundwater is present throughout the region as an unconfined alluvial aquifer within the Younger and Older AlluYium underlying the site, and in the underlying Pauba sandstone. The bedrock is considered as moderately good water bearing aquifer, and can yield limited amounts of groundwater to domestic water wells from primary and secondary porosity. Regional groundwater within the graben basin occurs oyer a thick section of several hundred. feet, and is utilized by numerous domestic, municipal, and irrigation water wells. Localized perched groundwater may be present at the site and typically occurs at the base of the bedrock-weathered zone. Perched groundwater is the result of local winter season percolating surface waters collecting over low permeability silt layers within the upper weathered Pauba sandstone. No springs or seeps were reported on the subject site. Additional information concerning the on-site hydrogeologic conditions may be obtained, if required, through the review of available water well driller logs, and by additional on-site hydrogeologic investigation under separate study. 4.0 FAULTING & SEISMICITY - 4.1 Faultina- No surficial or other evidence of active or potentially active faulting was observed at the subject site during our field investigation. The subject site is not included in any Earthquake Study Zone for fault hazard. The Wildomar Fault Zone located approximately 1/2 miles to the northeast, the Wolf Valley Fault 1.75 miles to the southwest, and the San Jacinto Fault Zone located approximately 21.0 miles to the northeast are the closest Special Study Zone faults to the site. The Wildomar Fault Zone is considered to be a high angle and strike slip fault, strongly developed and clearly visible from aerial photographs. The Wolf Valley Fault is described as a high angle fault possibly induced due to groundwater withdrawal in the Wolf Valley (1988)(Iower Temecula Valley). The San Jacinto Fault Zone extends along the foothills of the San Timoteo Badlands, and at the base of the south San Jacinto Mountains. The fault zone is considered to be a complex zone of high angle normal and strike slip faults with multiple and discontinuous fault strands as wide as 2 to 3 miles (San Jacinto & Casa Loma Faults San Jacinto Graben Valley). There are several other faults within the greater Southern California area, which could effect the site in terms of ground shaking in the event of an earthquake. The following list includes some of these faults and their maximum probable earthquake magnitude (Richter): Z.V I JONATHAN L. ROSSI,CONSULTING GEOLOGIST · P.O. BOX 4018,BIG BEARLAKE,CALlFORNIA 92315. Alf,} ^ "i/I vi (' ~! if!' (~~ ,/ I' ~ ~!,/,! li!;';f ; ~ i\/:..!" i ./ :~(' A / ~ ~; :It' -"i!.~'ff' . 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" .4?^~ . / : g3 ~~ ; ~~ / ~., ~ .. ~.... ./ .. g g ; gt: c - w 6 ~ ~ f .....-;;;- , 0 ;;; _.~/~./. \ /~::;., /!- ',/ ," , ~-' ~ f- 1- ..-".. <;:,....-'.... 7' f . j r-- I~ ! ! I . i ! g l i I ! , , i 1 11 H ~i g. p n "I , i ! 1 , . , ",0 ;; ~~ i' f I , ~ "1 i i 1 i II i ~ , , ! ~ ~ ~ . . if :- = . - I l ni ~ 's t!t oil lli ." I'" I'll r "I ill .1 ,,, III .1 ;t ,. .. '. J .. ~f' II II! P ~I I !,:, t1l ," 'J Hi iJ I 1! I! " !f " ,! i!. I I ~. r' / / / ;/ , -1-. , . . - f I I ['" " If. I;. -, i: I!' f" 'ri H rK. il'l fl" I~: . ..& >hdli f~rfi~ 1 r . _I I r ';' IS I ~~f ,,; ~id~l ~;' 'i t -f'l II' If is ; ~i !" ! H.f ' ;0" ;.. jt .~ lJ" . if ! 'jZ ~ .~ ~ ti..rt. '. ~"ii'.IJ -r~~'" \'..'- .::.~,- , 'V~..,- . ! ! i i ci'; " "I- x;'" _10 --- ~\; \; i I I I I - / ... .' /, '/ [J'/ ,. .' i , I / i / / /' j/ F -// / ... T --- '-I- , / -' /; ~/; , , - I - I g g I m :s:~ I; )>C"> C"> G)m ZZ en~ ::j-l o- em eO o::U -lZ men ilio o ::uTi !llTl)>Z:S: Omz )> o)>o~"- ::u~ rO G)J: TI::u ::uO 0:>1 me ::u)> !:i~ ~e mm )>~ ::u en o - TI Z riS 611 "1 I i III "':0 -III !;g Q- ::l~ ~... ." J II! ;~ ;fi p '1l ,.. 1> -< '" r L Ii. I, : , < Ii' ' I: -.~ '. o o < I ,- ~ < . ;{r ~. \/ V '. , 'T1 as c: ;ll m Co) I I I I I !I I . I . I I I I I I I I -8- March 29, 1999 IN: 0990011.01 TABLE I REGIONAL ACTIVE OR POTENTIALLY ACTIVE CAUSATIVE FAULTS FAULT DISTANCE FROM SITE MAXIMUM CREDIBLE APPROXIMATE EARTHQUAKE (RICHTER MAGNITUDE) San Andreas Fault 41.0 mi. NNE 8.0 M San Jacinto Fault 21.0 mi. NE 7.5M Elsinore (Wildomar) Fault Y:. mi.SW 7.5M Banning Fault 37.0 mi. ENE 7.5M Whittier 50.0 mi. NNW 7.5M Sierra Madre/Cucamonga 53.0 mi. NW 7.5M 4.2 Seismicitv- Based on information provided by CDMG Map Sheet 23 - Greensfelder; CDMG OF 92-1, 'Peak Accelerations from Maximum Credible Earthquakes in California - Caltrans 1992'; and Seed & Idriss . Ground Motion and Soil Liquefaction During Earthquakes' (Earthquake Engineering Research Institute), the following conditions were determined for ground accelerations for specific earthquake events at or near the subject site. Maximum credible earthquake magnitudes listed in CDMG OF-92-1 and associated bedrock accelerations are presented in TABLE II below. The subject site should perform essentially as a bedrock or stiff soil site because of the nature of the bedrock at the proposed graded pad site. Groundshaking and ground surface deformation will occur to a greater extent at an alluvial site than at a bedrock site. The Pauba sandstone can be considered stiff alluvial soil or soft bedrock. Review of CDMG Map Sheet 54, which is presented in CDMG OF-92-1 as a peak ground acceleration contour map includes the area of the subject site within the .6 g acceleration contour, one of the highest ground accelerations for southern California. 7-A I JONATHA.N L. ROSSI,CONSULTING GEOLOGIST. P.O. BOX 4018,BIG BEARLAKE,CALlFORNIA 92315. I I I I I . . . . . I I I I I I I I -9- March 29, 1999 IN: 0990011.01 TABLE II MAXIMUM CREDIBLE EARTHQUAKE PEAK GROUND ACCELERATION REPEATABLE GROUND ACCELERATIONS CAUSATIVE FAULTS FAULT DISTANCE MAGNITUDE PEAK REPEATABLE ACCELERATION ACCELERATION WILDOMAR 1/2 mi. 7.5 M .73 9 .475 9 SAN JACINTO 21.0 mi. 7,5M .250 9 .165 9 SAN ANDREAS 41.0mi. 8.0 M .175 9 .113 9 BANNING 37.0 mi. 7.5M .155 9 .101 9 WHITTIER 50.0mi. 7.5 M .100 9 .065g CUCAMONGA 53.0mi. 7.5M .080g .052g . Repeatable ground acceleration =.85 of maximum 'g'. Peak ground accelerations are provided for use by the soils engineer and the structural engineer in foundation design where applicable. Repeatable ground accelerations are not used by the engineering community at this time, but are provided here for the layman. Repeatable ground accelerations are comparable to dampened groundshaking. These ground acceleration values are for bedrock accelerations, and can be applied for any seismic condition stability evaluation of the subject site. Earthquake design criteria presented in the current adopted Uniform Building Code, or in the County of Riverside Building Code Seismic Design Section, or design provided by the structural engineer and soils engineer in accordance with these requirements, whichever takes precedence, should be applied to the proposed development. Other active or potentially active faults in the region will probably prOduce less sever effects on the site as a result of an earthquake event, and considering fault to site distances will probably have a less sever to negligible effect on the site. (see Table II above). '7,:5 I JONATHA,N L. ROSSI,CONSULTING GEOLOGIST · P.O. BOX 4018,BIG BEARLAKE,CALlFORNIA 92315 . I I I m m m . . . . I I I I I I I I -10- March 29, 1999 IN: 0990011.01 4.3 SecondarY Seismic Hazards - The potential for secondary seismic effects such as liquefaction due to the presence of granular sediments, shallow groundwater, and nearby active faulting capable of generating large earthquake events should be evaluated by the soils engineer. Based on our geologic observations at the site, and knowledge of the geology of the area, we do not consider the bedrock (Pauba Sandstone) at the location of the proposed building pad (as shown on Figure 2), to be a high risk for liquefaction. Other secondary seismic effects such as differential settlement/compaction, ground surface rupture due to fault movement, or ground surface rupture due to lurching is not considered likely, but cannot be ruled out due to the faulted nature of the region and the close proximity of active faulting. Ground surface rupture is suspected to have occurred along the Wildomar Fault in the past, at the fault location. Seismically induced land sliding is not common in the Pauba sandstone, and is considered unlikely to effect the subject site. Other potential secondary seismic hazards: tsunami, and seiches flooding due to reservoir failure are considered nil due to the site location, and nature of the bedrock deposits. 5.0 CONCLUSIONS & RECOMMENDATIONS - 5.1 Conclusions - o The subject site is suitable, in terms of the on site geologic conditions, for the proposed residential construction. Topsoil and Pauba Fm. sandstone bedrock should not present any significant geologic impediment to the excavation of the residential building pad and foundation footings. Footings cannot be founded in porous, unsuitable soil materials as per the soils engineer. o The subject site is close (1/2 mile) to the Wildomar Fault Zone. There are no reported or mapped traces of the fault close (adjacent) to, or on the subject site. Strong groundshaking (secondary seismic hazard) is considered a possibility should a medium to large earthquake event occur on the Wildomar Fault adjacent or close to the subject site. 1...'" IJONATHAN L. ROSSI,CONSULTING GEOLOGIST · P.O. BOX 4018.BIG BEARLAKE,CALlFORNIA 92315. I I I I I I I I I I I I I . I I I I -11- March 29, 1999 IN: 0990011.01 5.2 Recommendations- o Footina Insoection - The footing excavation should be inspected for competency by the soils engineer or the engineering geologist prior to the setting of reinforcing steel bar, or any imported sand or gravel base. o Groundshakina - Due to close proximity of the active Wildomar Fault, the structural engineer should consider seismic peak accelerations and groundshaking criteria in the steel reinforcing design for the residential foundation. o Drainaae Control - Any proposed cut slope exceeding 10 ft. in height should have a drainage 'V' brow ditch (24" wide, 12" deep) cut across the top of the proposed cut slope, set back 3 feet from the top of slope. The brow ditch should be lined with concrete grout. Drainage from all sources should not be allowed to flow over any proposed cut or fill slope faces. o Landscaoe Veaetation - Any proposed cut slopes should be planted with standard grasses and indigenous plants (hydroseed) possibly using a landscape stability growth net on the slope face. Deep-rooted vegetation should be planted in order to increase slope surficial stability over time. All landscaping design and plant type should conform to Riverside County landscaping guidelines. o Cut Slooe - Review of the Precise Grading Plan (Figure 2) indicates that a 2:1 (H:V) cut slope is proposed for the north side of the graded pad. The slope is :t17.5 ft. in height, :t150 ft. in length. The cut slope should be inspected by the geologist when approximately one-half of the cut (8 ft.) is completed, and upon completion. o Other Soils & Geoloaic Insoections - Any proposed vertical cut slope for retaining wall, cut pad/foundation footing excavations, fill slope keys, or other graded exposures of bedrock should be inspected by the engineering geologist upon excavation. Any observed lineation, offset feature, fissure, slide feature, or other unusual geologic or soils condition should be inspected by the soils engineer and/or the engineering geologist prior to any further grading or construction. 1--1 IJONATHAN L. ROSSI,CONSULTING GEOLOGIST · P.O. BOX 4018,BIG BEARLAKE,CALlFORNIA 92315. I I I I I I I I I I I I I I I I I I -12- March 29, 1999 IN: 0990011.01 6.0 L1MITATIONS- This Engineering Geologic report section has been completed by Jonathan L. Rossi, Consulting Geologist, Lakeshore Engineering, and licensed or certified subcontractors. to Lakeshore Engineering. It should be noted that J.L. Rossi, Consulting Geologist has been retained for the purposes of providing geologic interpretation of existing and gathered data, to provide the geology portion of the Preliminary Geotechnical Investigation. Our conclusions and recommendations are based solely on the data made available to us from one site visit, and information made available by Lakeshore Engineering. Our work has been performed in accordance with the professional practices currently accepted in the Geotechnical Consulting Industry today. No warranty is either expressed or implied. Should you have any questions conceming this Letter Report of Existing Geologic Conditions please do not hesitate to contact me at (909) 584-2084. ~~o' ,:;..S (?c:;> ~ JONATHAN ~j l. SINCERELY YOURS; ROSSI s CERTIFIED * ENGINEERING V ' \ Jl GEOLOGIST ~r. No. 1460 ~'(- ~~F CA~ Vi> IJONATHAN L. ROSSI,CONSULTING GEOLOGIST. P.O. BOX 4018,BIG BEARLAKE,CALlFORNIA 92315. I I I I I I I :1 I I I I I I I I I I IN: 0990011.01 APPENDIX IJONATHAN L. ROSSI,CONSULTlNG GEOLOGIST · P.O. BOX 4018,BIG BEARLAKE,CALlFORNIA 92315. -z,..a.. I I I I I I I I I I I I I I I I I I IN: 0990011.01 Page 1 of 2 REFERENCES Association of Engineering Geologist, 1973 - Earthquake Recurrence Intervals on Major Faults in Southern California, AEG Special Publication October 1973; D.L. Lamar, P.M. Merifield, RJ. Proctor. California Division of Mines & Geology - 1974; Map Sheet 23, Maximum Credible Rock Accelerations; R Greensfelder. - 1992; Peak Acceleration from Maximum Credible Earthquakes in Ca.; DMG Open-File Report 92-1; L. Mualchin, & A.L. Jones. ----- 1990; CDMG Map Sheet 54; unpublished for CalTrans. - 1954; CDMG SR 43; Geology of a Portion of the Elsinore fault Zone, California; John F. Mann, Jr. - 1977; CDMG SR 131; Recency & Character of faulting Along the Elsinore Fault Zone in Southern California; M.P. Kennedy --- 1988 - Summary Report: Fault Evaluation Program, 1986-1987, Mojaye Desert and Other Areas - Open File Report 88-1 LA; E.W. Hart, W.A. Bryant, J.E. Kahle, M.W. Manson, & E.J. Bortugno. -- 1967 - Geologic Map of California, Map No.1, Santa Ana Sheet; Jennings, C.w. - 1983 - The 1983 Coalinga, California Earthquakes, CDMG Special Publication 66, J.H.Bennelt & RW.Sherburne, Editors. Dudley, Paul H., 1935 - Geology of a Portion of the Perris Block, Southern California; California Division of Mines, California Journal of Mines & Geology Vol. 31, No.4, October 1935. Earthquake Engineering Research Institute, 1982 - Ground Motion and Soil Liquefaction During Earthquakes; H.Bolton Seed & I.M. Idriss. Pub: EERI Berkley, California.; ISBN 0943198240 Earthquake Engineering, 1970 - Robert Wiegel, Coordinating Editor; Pub: Prentice-Hall, N.J., ISBN 132226464. Earthquake Engineering, Damage Assessment and Structural Design, 1983 - S.F. Borg; Pub:Wiely Heyden, Ltd.; ISBN 0471262617. ?P I JONATHA.N L. ROSSI,CONSULTING GEOLOGIST. P.O. BOX 4018,BIG BEARLAKE,CALlFORNIA 92315 . I I I I I I I I I I I I I I I I I I IN: 0990011.01 Page 2 of 2 REFERENCES Geological Society of America, 1982 - Neotectonics in Southern California, Guidebook Field Trip No.3, 4, 14. 1986 - Neotectonics and Faulting in Southem California, Guidebook Field Trips 10, 12, 18. 1987 - Paleoseismicity and Active Tectonics, The Structural Geology and Tectonics Division, GSA. Grey, Cliffton H.,Jr, 1961 - Geology of the Corona South Quadrangle and the Santa Ana Narrows Area, Riverside, Orange & San Bernardino Counties, California., and Mines and Mineral Deposits of the Corona South Quadrangle, Riverside and Orange Counties, California; California Division of Mines and Geology Bulletin 178. lnstution of Mining & Metallurgy, 1981 - Rock Slope Engineering, 3rd Edition; E. Hoek & J.w. Bray; Pub: lnst. Mining & Metallurgy, London ISBN 0900488573 South Coast Geological Society, 1983 - Geology of the Northern Elsinore Trough, Annual Field Trip - 1983. United States Geologic Survey - 1985; PP 1306; 'Earthquake Hazards in the Los Angeles Region'; J.1. Ziony. Webber, Harold F.,1977 - Seismic Hazards Related to Geologic Factors, Elsinore and Chino Fault Zones, Northwestern Riverside County, California. MAPS UTILIZED USGS 71/2' Temecula Quadrangle Topographic Map 1975 rev. USGS 71/2' Bachlor Mtn. Quadrangle Topographic Map 1973 rev. USGS 71/2' Peachanga Quadrangle Topographic Map 1988 rev. CDMG Special Study Zone Map (Earthquake Fault Zone Map), Temecula Quadrangle 71/2' Revised Official Map January 1, 1980. CDMG Special Study Zone Map (Earthquake Fault Zone Map), Peachanga Quadrangle 71/2' Revised Official Map January 1, 1980. - 1967 - Geologic Map of California, Map No.1, Santa Ana Sheet; Jennings, C.W. ?\ IJONATHAN L. ROSSI,CONSULTlNG GEOLOGIST. P.O. BOX 4018,BIG BEARLAKE,CALlFORNIA 92315.