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468, Construct a stable and permit , Studies & ReportsLIMITED GEOLOGIC REPORT on Property at 2862 Palos Verdes Dr. North Rolling Hills, CA 90274 For Franz Fischer By A. G. Keene residential lot development groundwater environmental impact ARTHUR G. KEENE Engineering Geologist. E.G.16 Franz Fischer 2862 Palos Verdes Drive, North Rolling Hills, CA 90274 (213) 541-2112 December 8, 1991 Subject: Limited Geologic Investigation 2862 Palos Verdes Dr. North. Dear Mr. Fischer, As you requested, herein is presented a limited geologic investigation report of your premises consisting of an interpretation of basic bedrock structure under your site that supports an existing fill slope, analyzed by NorCal Engineering. Their report dated November 15, 1991. LOCATION The site is located south and upslope of Palos Verdes Dr. North, as shown on Figure I, Location and Geological Map. BACKGROUND INFORMATION The original pad was graded into a natural slope in 1962 followed by development in the early 1970's. A file for this development was not available at the Los Angeles County Dept. of Public Works. A geologic report may never have been submitted. However, a limited geotechnical investigation for a proposed garage addition in 1987 was utilized for this study. The investigation was done by Action Geotechnical Consulants, Inc. Also, NorCal Engineering data base was utilized. Their principal concern was the relative stabiliy of an existing fill placed in the front yard area. 1 2. • 1. A 96 81 94 y. 1,41A 1 r. A34 A 93 •••"` • KEY Qter Qsw Tma 01 s terrace deposits slope wash bedrock attitudes bedrock (Altamira ' shales) landslide A' - cross section A -A' 86 87 sl •Nf X:<•• • Map Sources: - -c •1 62 1,' po 63 / 7/4 ...,-7rsge..71)Nya;%Ws) Scale: 1" = 1000' 0 — Qier 0 4.1 5 GEOLOGIC MAP by C.D.M.G. •-• 6 7 7/70.1, DTU 00,4 • - AU , 1) C. - 1976- Cleveland 2) Zoning Map, City of Rolling Hills /76 •17 7 - - . ;a • L ',,,.7:1',:„,,,' \,, \II(' 4 i I :1-...,-,60• . .„..„1.,$ 4.,...\..\•\-14'.• 4, '.. .. 4,0 I o, .. ft s . t.,...• ,,...,.., ...... , ; .-'11--, ',•-7 / . 6 ft •:•11/./. 7 /31 1., • • • • • ,-.., 'x'• ; ffl, n.....` ..ft• a. ''''' .4.•')Z -.. ad 14,•-s 1.5," ... 7.• a 'hi .4-il•-•": '''.....' . -•,:'''-.1,X , . /IS • yl--- _____? • ,t. "" AO , ...0,..ret *- ' ''' " ' ' -.:,, t 44q , -^ ,, 4 . — , ... • 0,- 1 ' Mrsi.44;/..rA .07 I / ISO/AT ,/ .•:... 1 / 1 i / i' /M/" 1,x; r3,1 '.,. 2862 _ -,/4 I •7 7 r n 74_ \ 71. P41.6.1 14601., DRIVE N04,14 0 RI • ...wrO1W071-q-a7.4-74-.. 44=1;7. .:0”.• ,03 FIGURE I LOCATION AND GEOLOGIC MAP for Palos Verdes Drive North el 3. Other sources of information are covered under References. No subsurface investigation was undertaken for this geologic investigation. However, the lot adjacent to 2862, on the north-west side, the address of which is 2864 P.V. Dr. No., is currently being developed. Excavation for a deep key -way was observed and recorded for bedrock structural control. This information is shown on Plate I, Geologic Map and Plot Plan, (Appendix). REFERENCES: Limited Geotechnical Investigation 2862 Palos Verdes Dr. North - May 30, 1987 by Action Geotechnical Consultants, Inc. Attitude of Tma N63W, 75 NE Geology Section file for 2860 P. V. Dr. North attitudes by Emil Dimetteo: N35W, 35 NE - sandy shale, platy N55W, 40 NE N4OW, 30 NE - N5OW, 20 NE Six pits, two of which encountered massive diatomite/siltstone. Geology Sections file for #6 Roadrunner attitudes by Lockwood. Associates N47-65E, 15-25 SE - sandy diatomaceous shale N56E 36 SE - very fine grained sandstone and diatomaceous shale Geology Section file for #4 Roadrunner Geologic Report by J. Riccio, Pacific Soils - landslide is locatedon westerly property line, A. G. KEENE, STATE CERTIFIED ENGINEERING GEOLOGIST NO. 16, Tel. (213) 537 6615 2601 E. Victoria St., 1 308, Rancho Dominguez, CA 90220 extending westerly off -site; bedding into slope., No measured attitude given in text. No map on file. Limited Geotechnical Investigation of Existing Fill Slope 2862 Palos Verdes Dr. North by NorCal Engineering - Report dated November 15, 1991. Map Sheet 27, California Division of Mines and Geology by George Cleveland, 1976. GEOLOGIC STRUCTURE Available literature indicates the site is underlain by a steeply dipping anticline as shown on Figure 2, Geologic Cross -Section A -A'. According to NorCal Engineering, the graded pad rests on bedrock of the Altamira shales of the Monterey formation of Miocene age. This bedrock is in contact withnatural slope wash. materials which in turn are overlain by fill soils, recently placed. A contact line between slope wash materials and bedrock shales exists under the house at pad elevation 577. Subsurface information off -site to the northeast and upslope to the south were utilized for the anticlinal interpretation of the structural relationship underlying the site. This information is platted on Figure I for ready reference. On site information from Action Geotechnical Consultants indicated the apex of the anticline is approximately under the house, or perhaps 50-60 feet south and upslope of the pad for 2862. ENGINEERING GEOLOGY OF THE SITE No evidence of landslide or slump failure exists on the site. A. G. KEENE, STATE CERTIFIED ENGINEERING GEOLOGIST NO. 16, Tel. (213) 537 6615 2601 E. Victoria St., # 308, Rancho Dominguez, CA 90220 600 - i 590 77AZ W 580 - L z CD570- CC 560 - 1 w 550 - 540 /1/63W, 73NE (/elo on 6eofec4. MyJo,/ 96'7) _. Tm2 A/fainica, s/,a/es - far, /o r'st si/fs71onc and ve/y {inc f/v/iTed Sar,dsf0r1e w%fti orark ri'/.eewoces xi/Zs/one /tfon �oofsriin,�a/ %fay3g /9,97 N 14 E EXISTING RESIDENCE (1975) (28G2 PalosVcj.des2r;ve/Sio.) --7 ORIGINAL GRADE �� (1962) 8-3 CLAY WITH SHALE \ \ \ \ 0 20 FEET 40 SHALE BEDROCK SECTION A -A \� �Not-Cg/ En9/neerin9; ///is/9J) FINAL GRADE (1991) SLOPE GRADE (1990) B-1 2 FILL SOILS CLAY WITH SHALE ��NEW RETAINING RECOMMENDED 2 TO 1 FINAL SLOPE SETBACK LINE 1.5 WALL DRIVEWAY NorEo - a}t/h/des shown are CO/27po/7e 2'S of frve dips on secfion. See Piyvre Z 7cor- /oc a71/407 o f svIsd.-fdce 6eoiroc, 6edoiay af/n`rddes exf,-.,cfed fror» references crJce.d r,' /exf Figure 2 GEOLOGIC CROSS SECTION A - A' Interpretation based on subsurface data by others (See References cited 12/5/91 A. G. Keene 6. Drainage is positive. No ponding can occur. Surface drainage will be in the form of sheet wash off the recently placed fill, and down the access driveway leading to Palos Verdes Dr. North. Drainage eastward of a graded pad for a future barn will be toward a drainage ravine east of this pad, as shown on Figure I and the C.D.M.G. map provided. CONCLUSIONS No landslides or slump failures exist on site. None is shown by C.D.M.G., Map Sheet 27. The pad as graded appears to be grossly stable. The geologic structure is shown to be self supported directly north of the site pad. Bedding planes dip into the slope at an angle steeper than the natural grade. The gross stability of the lot at 2862 P.V.Dr. No. will be further enhancedby geotechnical work currently underway for 2864 P.V. Dr. No., consisting of a deep buttress key -way followed by a buttress fill. Observation of the excavation for the key -way by this author revealed no evidence of massive ground failure in the bedrock. Altamira shales are dipping at 25-30 degrees northeast on a strike of about N70W. Daylight conditions may therefore exist into the adjacent drainage ravine to the west of lot 2864. Of course, the purpose of the buttress key -way is to prevent any future potential for bedrock failure into the drainage ravine. Drainage ponding and erosion do not exist on the site as currently graded. CLOSURE The basic information for this geologic study and interpretation A. G. KEENE, STATE CERTIFIED ENGINEERING GEOLOGIST NO. 16, Tel. (213) 537 6615 2601 E. Victoria St., 1 308, Rancho Dominguez, CA 90220 7. is based upon data by others, on -site and off -site. This data has, to my knowledge, been accepted by the proper review agencies. No other warranty for the accuracy of this data is given by this author and none should be implied. A. G. Kee Distri: Fra Davi File RED GE: vR G. A-(41 4 No. 16 ��,, Q' CERTIFIED °1 ENGINEENG z F i s cEhCe r f S4T) Ex 6--P Z e ihb z*"&” (a.) A. G. KEENE, STATE CERTIFIED ENGINEERING GEOLOGIST NO. 16, Tel. (213) 537 6615 2601 E. Victoria St., # 308, Rancho Dominguez, CA 90220 •t� • — 550 1962 TOPO 550 --- PROPERTY LINE —i 560 ---- 575 • • CONCRETE DECK •• 550 B-4 575 B-1 TOP OF SLOPE -- 565 ff18-3 Qaf/QB v/Tma 570 — `-. ,40 2.5 580 • lPOOL PUMP /llol"e Togo.- 80 B-2 • • • . • A • _ 550 54s ssa 585 .. . 1st iu.in „iii. 555 2862 Palos Verdes Dr. North 0 '570 NORTH 20 FEET PLOT PLAN 40 590 FISCHER RESI^EMCE IN ROLLING HILLS, CA. NOVEMBER, 1991 and GEOLOGIC MAP PLATE Ii • • NorCal Engineering SOILS AND GEOTECHNICAL CONSULTANTS 10571 CALLE LEE SUITE 155 LOS ALAMITOS, CA 90720 (714) 826-4231 (213) 267-0125 FAX (714) 826-2514 • November 15, 1991 Project Number 3597-91 Mr. Franz Fischer 2862 Palos Verdes Drive North Rolling Hills, California Re: Limited Geotechnical Investigation of Existing Fill Slope - Located at 2862 Palos Verdes Drive North, in the City of Rolling Hills, California Dear Mr. Fischer: As per your request, this firm has performed a limited geotechnical investigation of the existing fill slope at the subject site. This work was done to evaluate the degree of compaction within the new fill slope, which was completed in September, 1991. Our conclusions and recommendations are provided for use in final grading plans being developed by Dave Breiholz and Associates. BACKGROUND INFORMATION The existing single story residence was built in the early 1970's by excavating into the slope along the south property line to form a level building pad. The original slope was at a 5 to 1 gradient consisting of fine-grained colluvial soils overlying native sedimentary bedrock materials. A private driveway was graded from the upper building pad down to Palos Verdes Drive North, as shown on Figure 1. N ►O V 1 9 1991 Of Polling Hills RECEIVED NOV 191991 D. C. BREIHOLZ & CO., INC. Page 2 8/19/91 Project Number 3597-91 • • • RECENT GRADING OPERATIONS During August and September, 1991, a new fill slope was constructed north of the existing residence to create a large building pad area. This work was supervised by the owner reportedly using heavy construction equipment to compact the imported fill soils. The large cobbles, boulders and concrete pieces from a demolished swimming pool were placed at the bottom of the fill slope, near the lower retaining wall along the north property line. This layer was confirmed in our recent field explorations. The present slope is up to 10 feet high at a 1.5 to 1 gradient ascending from the top of the new retaining walls. LIMITED FIELD INVESTIGATION A limited field investigation was performed consisting of the placement of four exploratory borings along the perimeter of the upper building pad area, as shown in Figure 2. The maximum depth of exploration was 15 feet penetrating into rock materials and native shale bedrock, which caused refusal of the auger. The excavations revealed fill soils to a depth of 12 feet which were soft to medium stiff and moist as evidenced by our laboratory findings. The low density fill soils were underlain by stiff colluvial soils overlying native shale BEDROCK which is considered high in expansion potential. No groundwater was encountered in any of the excavations. Undisturbed samples of the subsurface soils were obtained to perform laboratory testing and analysis for direct shear, consolidation tests and to determine in -place moisture/densities. These undisturbed samples consisted of one inch rings with inside diameter of 2.5 inches. Bulk bag samples were obtained in the upper soils for expansion index tests and maximum density tests. NorCal Engineering Page 3 8/19/91 Project Number 3597-91 • LABORATORY TESTS A. The field moisture content (ASTM:D 2216) and the dry density of the ring samples were determined in the laboratory. This data is listed on the log of excavations. B. Maximum density tests (ASTM:D 1557-78 were performed on typical samples of the upper soils. Results of these tests are shown on Table I. C. Direct shear tests (ASTM:D 3080) were performed on undisturbed and disturbed samples of the subsurface soils. These tests were performed to determine parameters for the calculation of the safe bearing capacity. The test is performed under saturated conditions at Toads of 518 lbs./sq.ft., 1,036 lbs./sq.ft., and 2,072 lbs./sq.ft. with results shown on Plate A. D. Expansion index tests in accordance with the Uniform Building Code Standard No. 29-2 were performed on remolded samples of the upper soils to determine the expansive characteristics and to provide any necessary recommendations for reinforcements of the slabs -on -grade and the foundations. Results of these tests are provided on Table II. E. Consolidation tests (ASTM:D-2435) were performed on undisturbed samples to determine the differential and total settlements which may be anticipated based upon the proposed Toads. Water was added to the samples at a surcharge of one KSF and the settlement curves are plotted on Plate B. NorCal Engineering Page 4 8/19/91 Project Number 3597-91 • • CONCLUSION AND RECOMMENDATIONS The upper fill soils recently placed were determined to have relative compaction values from 80 to 90 percent and are not in a suitable condition to provide support for any foundations, slabs -on -grade, or additional fill soils. All future grading operations shall be performed in accordance with the attached "Specifications for Compacted Fill Operations". All backfill adjacent to the retaining walls should be compacted to a minimum of 90% of the maximum density. Flooding or jetting should not be utilized in any trench or wall backfill. Any temporary excavation which is not properly shored should be constructed at one horizontal to one vertical slope. Care should be taken to provide or maintain adequate lateral support for all adjacent improvements and structures at all times during the grading operations and construction phase. The existing 1.5 to 1 fill slopes should be flattened to a 2 to 1 gradient and groundcover installed prior to the upcoming rainy season. Concrete drainage ditches should be placed along the top of retaining walls to efficiently route any runoff into vertical drain pipes. NorCal Engineering Page 5 8/19/91 Project Number 3597-91 • RETAINING WALL DESIGN PARAMETERS Active earth pressures against retaining walls may be computed using equivalent fluid densities given below. These values are for the clayey on -site materials placed adjacent to the walls at the following ground slopes above the walls: Surface Slope of Retained Materials Equivalent Fluid (Horizontal to Vertical Density (Ib./cu.ft.) Level 45 5 to 1 47 4to 1 50 3 to 1 55 2 to 1 60 1.5 to 1 90 The following values may be utilized in resisting lateral Toads imposed on the structure. Requirements of the Uniform Building Code should be adhered to when the coefficient of friction and passive pressures are combined. Coefficient of Friction - 0.35 Equivalent Passive Fluid Pressure = 200 lbs./cu.ft. Maximum Passive Pressure = 2000 lbs./sq.ft. The passive pressure recommendations are valid only for native shale bedrock and stiff colluvial soils. NorCal Engineering Page 6 8/19/91 Project Number 3597-91 • • SLOPE STABILITY EVALUATION The existing 1.5 to 1 fill slopes should be trimmed at a 2 to 1 gradient to meet local building criteria as determined by David Breiholz and Associates personnel. The low density fill soils are judged to be grossly stable for slope heights of up to 10 feet., as shown on Plates C and D. The slope face should be planted with ground cover immediately after trimming at a 2 to 1 gradient, as shown on Figure 3. No structures or slabs -on -grade are planned to be built within the newly placed fill pad area. SETTLEMENT SUBSIDENCE Due to landscaping and inclement weather conditions, the moisture content in the fill soils may increase causing additional settlements. This will result in subsidence of the upper graded pad on the order of 0.2 feet at the top of the fill slope. CLOSURE The recommendations and conclusions contained in this report are based upon the soils conditions uncovered in our tests excavations. No warranty of the soils condition between our excavations is implied. NorCal Engineering should be notified for possible further recommendations if if unexpected or unfavorable conditions are encountered during the construction phase. It is the responsibility of the owner to ensure that all information within this report is submitted to the Architect and appropriate Engineers for the project. This firm should have the opportunity to review the final plans to verify that all our recommendations are incorporated. Our representative should be present during the grading operations to certify that such recommendations are complied with in the field. A pre -grading conference should be held between the developer, general contractor, grading contractor, grading inspector, architect and soil engineer to clarify any questions relating to the grading operations and subsequent construction. NorCal Engineering • • • Page 7 8/19/91 Project Number 3597-91 This report and all recommendations contained herein are subject to review by the controlling authorities for the project. We appreciate this opportunity to be of service to you. If you have any further questions, please do not hesitate to contact the undersigned. Respectfully submitted, NORCAL ENGINEERIN Keith D. Tucker Project Engineer R.G.E. 841 =sa NorCal Engineering Troy D. Norrell President • • SPECIFICATIONS FOR PLACEMENT OF COMPACTED FILL, PREPARATION Any existing low density soils and/or saturated soils shall be removed to competent natural ground under the inspection of the Soils Engineering Firm. After the exposed surface has been cleansed of debris and/or vegetation, it shall be scarified until it is uniform in consistency, brought to the proper moisture content and compacted to a minimum of 90% relative compaction (in accordance with ASTM: D- 1557-78). FILL SOILS The on -site soils or approved import soils may be utilized for the compacted fill provided they are free of any deleterious materials and shall not contain any rocks, brick, asphaltic pavement, concrete or other hard materials greater than 8 inches in maximum dimension. Any import soil must be approved by the Soils Engineering firm a minimum of 24 hours prior to the importation on site. PLACEMENT OF COMPACTED FILL SOILS, The approved fill soils shall be placed in layers not in excess of six inches. in thickness. Each lift shall be uniform in thickness and thoroughly blended. The fiil soils shall be brought to within 15% of the optimum moisture content, unless otherNise specified by the Soils Engineering firm. Each lift shall be compacted to a minimum of 90% relative compaction (in accordance with ASTM: D-1557-78) and approved prior to the placement of the next layer of soil. Compaction tests shall be obtained at the discretion of the Soils Engineering firm but at a minimum of one test for every 500 cu. yards placed and/or for every 2.0 feet of compacted III placed. NorCal Engineering • • • The minimum relative compaction shall be obtained in accordance with accepted methods in the construction industry. The final grade of the structural areas shall be in a dense and smooth condition prior to the placement of slabs -on -grade or paved areas. INSPECTION All bottoms of excavations shall be inspected and approved by the Soils Engineering firm prior to the placement of any compacted fill soils. These excavations shall also be inspected by the respective governing building agency as required. The grading operations shall be inspected by the Soils Engineering firm as deemed necessary. A 24 hour notice must be provided to this firm prior to the time of our initial inspection. UFASONAL LIMITATIONS No fill soils shall be placed, spread or compacted during unfavorable weather conditions. When the grading is interrupted by heavy rains, compaction operations shall not be resumed until approved by the Soils Engineering firm. NorCal Engineering • SHEAR STRESS (PSF) • 2500 2000 1500 1000 500 0 0 500 1 BORING SYMBOL NUMBER X 1 0 3 C3 1000 DEPTH (FEET) 2.0 3.0 2.5 1-- I 1500 2000 2500 3000 NORMAL STRESS (PSF) •0 C (DEGREES (PSF) 15 225 22 100 17 575 DRY MOISTURE DENSITY CONTENT (PCF) (%) 82.6 7.3 87.0 6.a__ 97.4 12.2 NOTE: TESTS PERFORMED ON SATURATED SAMPLES UNLESS SHOWN BELOW. (FM) = FIELD MOISTURE SAMPLES REMOLDED AT 90% OF MAXIMUM DRY DENSITY PER ASTM D 1557-78 STANDARDS. (R) = REMOLDED *Native Soils • NorCal Engineering SOILS AND GEOTECHNICAL CONSULTANTS Plate A DIRECT SHEAR TEST RESULTS PROJECT 1 DATE • 0 2 4 E 8 1C 12 0.1 * SYMBOL X 0 0 0.5 1.0 BORING NUMBER 1 1 2 DEPTH. (FEET) 4.0 6.0 8.5 NORMAL PRESSURE (KSF) DRY DENSITY (PCF) 101.4 91.6 94.4 MOISTURE CONTENT (%) 8.5 8.9 22.8 NOTE: WATER ADDED AT NORMAL PRESSURE AT 1.0 KS' LIQUID LIMIT (%) 10 2) 40 PLASTICITY INDEX (%) . COMPRESSION (FM) = FIELD MOISTURE ---- REBOUND (R) = REMOLDED *Native Soils • NorCal Engineering SOILS AND GEOTECHNICAL CONSULTANTS Plate B CONSOLIDATION TEST RESULTS • • H �, C,'Ym TAYLOR CRITICAL HEIGHT METHOD: Hc = C "Ym (FS)SN WHERE Hc = VERTICAL HEIGHT OF SLOPE, FT. C = COHESION, PSF Ym = MOIST DENSITY OF SLOPE MATERIAL, PCF i = SLOPE ANGLE, DEGREES FS = FACTOR OF SAFETY SN = TAYLOR'S STABILITY NUMBER BASED UPON FRICTION ANGLE, 0' AND SLOPE ANGLE, i 0 = INTERNAL FRICTION ANGLE OF SOIL, DEGREES I. FOR 1.5 to 1 Existing Fill Slopes DIRECT SHEAR TEST DATA: = 19 0 , C = 150 psf, 'Ym = 90 pcf, 01= Tan --Tan 0 15° FS = 1.50, F.S. FOR i = 33.7, SN = 0.055 Hc = (150 psf) ( 90 pcf) (1.50) (0.055) NorCal Engineering SOILS AND GEOTECHNICAL CONSULTANTS 20 FT. Plate C GROSS SLOPE STABILITY ANALYSIS Fischer Residence PROJECT 3597-91 I DATE 11/15/91 • FS= TEMPORARY PIEZOMETRIC SURFACE SURFACE SOILS: RELATIVELY PERMEABLE /POTENTIAL .SLIP SURFACE 11 Op PARENT SLOPE MATERIAL, BEDROCK OR COMPACTED FILL; --� RELATIVELY LOW PERMEABILITY Reference: U.S. Geological Survey Professional Paper 851 C + (7- m7w) z cos20 tan0 (7—m7M) tan(t)C 7 Z sin j3 cos j3 7. tang 7. Z • sing • cos tr3 WHERE F.S. = FACTOR OF SAFETY 7 = UNIT WEIGHT OF SOIL 714 = UNIT WEIGHT OF THE WATER C = COHESION = ANGLE OF SHEARING RESISTANCE Z = VERTICAL DEPTH OF THE SLIP SURAFCE m = FRACTION OF Z SUCH THAT mZ IS THE VERTICAL HEIGHT OF THE TEMPORARY WATER SURFACE ABOVE THE SLIP SURFACE 1.5 to 1 = = SLOPE ANGLE. SEE BELOW 90 pcf 62.4 pcf 150 psf 19 deg. 3.0 feet 1.0 33.7 deg. (90-62.4 pcf)(tan 19°) + 150pcf (90pcf)(tan 33.7°) (90Pcf)(3')(sin 33.7°)(cos 33.7°) I.FS=0.16 = 1.20 = 1.36 for 1.5 to 1 Slope II.FS=0.21 = 1.39 = 1.60 for 2 to 1 Slope � NorCal Engineering SOILS AND GEOTECHNICAL CONSULTANTS Fischer Residence PROJECT 3597-91 I DATE 1 1 /15/91 Plate D SURFICIAL SLOPE STABILITY ANALYSIS NM - 550 -- 1962 TOPO 550 "-I 560 PROPERTY LINE 570 575± • ,.� _ _ • _• CONCRETE DECK • • , - • - 550 555 • B-1 TOP OF SLOPE B-4 , — 565 575 B-3 .. py • ....:,: w....... : • � .u,�.'�ff. y4'fl..iii��Cf ----- <. - '.<3s": : +,�cF;:`y ,,� y.. , 4., /:: f/%`'? /i �Z:.+,k:ig'?1.0..0:11.4 -m* .cam -.:.:. ;Nrtivv!"w:2. . • -• '•,iY^�>,""C.$.'/-•.`.`Y;;i•i%�.Ni�S.s./'`..?:n t,.;,`. r�.. -?-›.-•, ii'l.: ((:� " .2:•-: �� _ L.o,.a •�'ecinYrc:;uf'...%F/.: ;��/i�y/� n ^d 0•49z 1- lF! �i witi1•, 580 POOL L PUMP ........ 590 580 555 B-2 '550 RETAINING WALL 560 560 • • • - • CONCRETE DRIVEWAY •_/• • . • • ..,:• 585 • 545 550 PRO,oL. .4INF 555 _. 565 1991 TOPO ,•, 575 565 510 0 • • NorCal Engineering SOILS AND GEOTECHNICAL CONSULTANTS FISCHER RESIDENCE IN ROLLING HILLS, CA. JOB NO. 3597-91 NOVEMBER, 1991 NORTH 0 20 FEET .\ 560 PROPERTY LINEN sas 570 A PLOT PLAN 40 FIGURE 2 600- t • 590 _ I- w 580 - z 570 - 0 rl • cc LIJ 560 - La 550 - 540 - 0 EXISTING RESIDENCE (1975) ORIGINAL GRADE PAD EL. 577 �� (1962 ) 20 FEET We../T\'�T`(4,..c\"(/".\\// i 40 CLAY WITH SHALE B-3 SHALE BEDROCK SECTION A -A FINAL GRADE (1991) SLOPE GRADE (1990) B-1 2 1 RECOMMENDED 2 TO 1 FINAL SLOPE SETBACK LINE FILL SOILS 1 5 DRIVEWAY CLAY WITH SHALE NEW RETAINING WALL NorCal Engineering SOILS AND GEOTECHNICAL CONSULTANTS CROSS SECTION A -A FISCHER RESIDENCE IN ROLLING HILLS, CA. JOB NO. 3597-91 , NOVEMBER, 1991 FIGURE 3 ::$ UnY u►IU4$ Y 81 7.3 82.6 6/8 R 82 8.5 101.4 4/8 R 87 8.9 91.6 7/8 R 81 4.9 100.0 6/101 R 89 14.1 93.6 7/11 R 90 20.8 94.0 7/15 R SAMPLE TYPES CI Rack Care Standar: Split Spoon C Ring Sample 2C W 0 5- 10 — DESCRIPTION OF SUBSURFACE. MATERIALS THIS SUMMARY APPLIES ONLY AT THE LOCATION OP THIS BORING ANO AT THE flue OF DRILLING. SU1SURFACE CONOrONS MAY OIFFER AT OTHER LOCATIONS ANO MAY CHANGE AT THIS LOCATION WITH THE PASSAGE OF TILE. THE DATA PRESENTED IS A SIMPLIFICATION OF ACVA. CONOITIONS ENCOUNTERED. Fill Soils CLAY, silty, sandy, tan, medium stiff, damp with SAND, fine to median grained, silty, brown, dense, damp, clays and sands alternated with depth of boring Fill Soils CLAY, silty with shale fragments, dark grey, stiff, moist Rock at 13.0 feet - Could not penetrate. Could 15— not drive sampler full 12.0" at 12.0 feet due to obstruction .11 20 — 25 — 30 — 35 © Bulk Sammie JQ Jar Sample NorCal Engineering DATE DRILLED: 11 /8/91 EQUIP!£iT USED: Hollow Stem Auger GROUNDUATER LEVEL: Not encountered LOG OF BORING #1 PQO.;ECT ?ID.: .359 /-91 I DATE: • • A i 85 6.2 87.0 6/7 •R OESCRIPTICN OF SUBSURFACE MATERIALS TENS SUMMARY APPLIES ONLY AT TN! LOCATION OR nos OCRING ANO AT THE TIME OF DRILLING. SU*SUAFACE CONDITIONS MAY OIFFEA AT OTHER LOCATIONS ANO MAY CHANGE AT THRS LOCATION WITHIN! PASSAGE OF TINE. THE DATA PRESENTED IS A SIMPUFICATION OF ACTUAL CON01T10N3 ENCOUNTERED. Fill Soils SAND, fine to medium grained, silty, tan, med- ium dense, damp CLAY, silty with shale fragments, grey, med- ium stiff, damp, increase in sand content 82 9.3 86.4 5/3 R 5- with depth 90 22.8 94.4 8/15 R 91 22.0 95.0 17/22 R SAMPLE TYPES C I Rock Core t ; Standard Split Spoon CRing Sample 0 NATIVE SOILS 10- CLAY, silty with shale fragments, grey, stiff, moist -.. Diatomaceous Shale Bedrock, light grey, dense, (9amp 15- 20 - 25 - 30 - 35 © Bulk Sample JQ Jar Sample NorCal Engineering DATE ORILL.ED- 11/8/91 EQUIPIyENT USED: Hollow Stem Auger GROUNDUATER LEVEL: Not encountered LOG OF BORING #2 PROJECT MO.: 3597-91 I BATE: DRY I til:41 Y 95 12.2 97.4 7/13 R SAMPLE TYPES Rock Cr!a E� Standard Split Spoon l�' Ring Sao l e y W O 0 r 10 — 15- 20- 25 — 30 — 35 OESCRIPTICN OF SUBSURFACc MATERIALS THIS gUNMARY AP$USS ONLY AT THt LOCATION Of THIS BORING ANC AT THE fluE Of ORIIllI+G SUZSURFACE CCNOITIONS MAY OIFFEN AT OTHER LOCATIONS ANO MAY CHANGE AT TNIS LOCATION WITH THE PASSAGE OF flue. me OATH PRESENTED IS A 311.1PUfICATICN Of AC 1AI. gNOIT1ONS !ENCOUNTERED. Fill Soils - Loose, damp Native Soils CLAY, silty with shale fragments, dark grey, very stiff, moist Auger would not penetrate dense clays © Bulk Saso1e JQ Jar Samole NorCal Engineering DATE DRILLED- 11/8/91 EQUIPMENT USED: Hollow Stern Auger GROUNDWATER LEVEL: Not encountered LOG OF BORING #3 PRO.;ECT MO.: 3597-91 I DATE: • • cd IiIIY Idlit41 Y 85 6.6 104.1 11/22 R 84 =25.0 85.6 7/9 R OESCRIPTICN OF SUBSURFACE. MATERIALS TINS SUMMARY APPLIES ONLY AT THE LOCATION Of THIS WRING ANC AT THE flss 0f ORIWIIG. SU*SURFACE CONOrONS MAY 0IFFER AT OTHER LOCAfl0N3 AN0 MAY CHANGE AT THIS LOCAfl0N A r.' THE PASSAGE OF TILE. THE DATA PRESENTED 13 A SIMPLIFICATION OF ACTUAL CONOIT10N3 ENCOUNTERED. Eill Solis SAND, fine to medium grained, silty, brown, dense, damp 5 — CLAY, silty with shale and marlstone fragments grey -brown, medium stiff, damp to moist 10- 90 21.9 94.2 11/16 R 88 24.2 92.0 10/30 R 15 20 — 25 — 30 — 35 Native Soils CLAY, silty, dark grey, stiff, moist Diatomaceous Shale Bedrock, light grey, dense, SAMPLE TYPES DATE GRILLED: 11/8/91 C I Rock Cr!o© Bulk Sample EQUIP!£;T USED: Hollow Stem Auger t'!� Standar: Split Spoon JQ Jar Sample • GROUNDWATER LEYEL:Not encountered R I Ring Sawle NorCal Engineering LOG OF BORING #4 PROJECT MO.: 3597-91 DATE: