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344, Addition to SFR and an additio, Studies & ReportsGEO-ETKA, INC. ESTABLISHED 1965 SOIL ENGINEERS AND GEOLOGISTS (714) 870.9800 FULLERTON BUSINESS CENTER 2524 EAST FENDER AVENUE • SUITE C • FULLERTON, CA 92631 GEO-ETKA, INC. ESTABLISHED 1985 FOUNDATION SOIL INVESTIGATION, ENGINEERING GEOLOGY PAVEMENT DESIGN. SLOPE STABILITY ANALYSIS COMPACTION CONTROL. PERCOLATION STUDIES MATERIAL INSPECTION AND TESTING FULLERTON BUSINESS CENTER 17141 870.0800 2524 EAST FENDER AVENUE • SUITE C • FULLERTON. CA 92631 FOUNDATION SOILS INVESTIGATION AND ENGINEERING GEOLOGIC INVESTIGATION AT No. 7 Williamsburg Lane Rolling Hills California FOR Mr. and Mrs. Charles Thornton No. 7 Williamsburg Lane Rolling Hills California 90274 Date: May 29, 1986 Job No: FG-2578-86 GEO-ETKA, INC. JOB NO: FG-2578-86 TABLE OF CONTENTS DESCRIPTION PAGE NO. Scope 1 Proposed Construction 1 Site Condition 2 Soil Condition 2 Exploration 3 Laboratory Testing 3 Conclusions Suitability of the Project 4 Strength Characteristics 4 Expansion Potential 4 Recommendations Foundation Design 5 Bearing Values 5 Footings Dimensions and Setbacks 5 Settlement - Total and Differential 5 Earth Pressures 6 Expansive Soil Criteria 6 General Drainage Recommendations 7 Section 309 Statement 7 Demolition and Tree Removal 7 Grading 8 I DESCRIPTION PLATES Shear Curve nArt Consolidation Curves "Bn GEO—ETKA, INC. JOB NO: FG-2578-86 and APPENDICES I Soil Classification and Sampler II Limitations III Engineering Geologic Investigation IV Geologic Map II GEO-ETKA, INC. JOB NO: FG-2578-86 Scope This report presents the results of our Foundation Soils Investigation and Engineering Geologic Investigation of the site of the proposed construction to be located at No. 7 Williamsburg Lane, Rolling Hills, California. The physical location and dimensions of the site are shown on the attached Plot Plan, Appendix IV. Investigation was authorized to determine the existing soil conditions at the site and to provide data and specific recommendations relative to the foundation design for the proposed structure(s). Please refer to Appendix II for an explanation of the limitations inherent in this field. Proposed Construction Proposed is an addition of a guest house to the existing single family residence. In addition, a retaining wall will be constructed. Wall loads of 2,000 p.l.f. have been assumed and utilized in the preparation of this report. Should final design loads vary significantly from those noted above, this office should be notified. 1 GEO-ETKA, INC. JOB NO: FG-2578-86 Site Condition The site of the proposed construction has a gentle slope in the area of the building. The Western section slopes down. It is bounded on the North by a house and on the South by a residence; on the East by Williamsburg Lane, and on the West by a drainage channel. With reference to the site investigated, the West is at a much lower elevation while the other 3 contiguous sides have matching contours. Grass and trees form the ground cover. An existing residence with detached stables are at the site as shown on the plan, Appendix IV. Soil Condition The on site in situ soil is a strata of soft clayey sandy silt. The top soil is supported by a layer of diatomaceous siltstone. The bedrock is very hard to sample. For details please refer to the Logs of the Trenches and the Plan. No ground water was noted. Localized man -placed fill was encountered in trench no. 2, only. All footings must penetrate this fill. The fill must be removed if the area is to be used for slab support. 2 GEO-ETKA, INC. JOB NO: FG-2578-86 Exploration The subsurface was explored by trenching with a backhoe to a maximum depth of 8 feet below the existing ground surface. The trenches were placed in strategic locations where the major structures are to be constructed in a manner to determine the subsurface conditions. Approximate locations of the trench is shown on the attached Plot Plan, Appendix IV. The trenches were logged by our geologist. Samples of both undisturbed and disturbed soils encountered were obtained for laboratory testing and observation. Logs of the trenches are shown on geology report. The soils are classified in accordance with the Unified Soil Classification System described on an attached Plate. This Plate also shows the type of sampler used in obtaining undisturbed samples. Laboratory Testing The field moisture content and dry densities of the soils encountered were determined by performing tests on the undisturbed samples. The results of these tests are shown on the Logs of trenches. Density and field moisture information is useful as indicators of the nature and quality of the material. Direct shear tests were performed on selected, undisturbed samples of the soils in order to determine the strengths and supporting capacities of the soils. The method of performing these tests is to saturate the sample, to extrude the sample into the test apparatus, to apply the normal load, and then to allow sufficient time to elapse to dissipate any excess hydrostatic pressure. The sample is then subjected to a strain -controlled single plane shear test. The method of applying the normal and shearing load is such as to allow the sample to change in volume without producing an associated change in the normal stress. The shearing stress is measured at a constant rate of strain of approximately 0.05 inches per minute. Selected samples of soil were tested at confining pressures similar to those of the materials in -situ. Additional specimens from the same samples were also tested at increased normal pressures in order to determine the increase in shear strengths associated with increased intergranular pressure. The test results are plotted graphically on Plate "A". The resulting values are on the following page. 3 Laboratory Testing (Cont'd) Angle of Internal Soil Type Friction (degrees) Clayey sandy silt Clayey sandy silt 17 20 1/2 GEO-ETKA, INC. JOB NO: FG-2578-86 Cohesion (p.s.f.) 345 185 Consolidation tests were performed on saturated specimens of the typical foundations soils. Consolidometers are designed to receive the undisturbed soil samples and brass rings in the field condition. Porous stones placed at the top and bottom of each specimen permit free flow of water into or from the specimen during the test. Successive load increments were applied to the top of the specimen and progressive and final settlements under each increment were recorded to an accuracy of 0.0001 inch. The final settlements so obtained are plotted to determine curves shown on Plates "B" and "C" Conclusions Suitability of the Project The site is suitable for its intended use, namely a guest house addition and a retaining wall. In designing the proposed structures, the criteria given in the design section should be adhered to. A) The construction of this project will not affect the stability of the surrounding structures, such as walls, electric poles, etc. . B) For this particular lot, this Foundation Soils Investigation and Engineering Geologic Investigation will be adequate. A Seismic statement is not deemed necessary. Please use U.B.C. Table 23.1 latest edition. C) This report is subject to approval by the governing agencies. Strength Characteristics The load bearing soils possess strength parameters adequate to support the proposed construction. Expansion Potential The on site surficial soil is classified as moderately expansive with an expansion index of 81. This is based on the test results conducted in accordance with U.B.C. 29-2. 4 GEO-ETKA, INC. JOB NO: FG-2578-86 Recommendations Foundation Design Continuous footings may be utilized for the design of the foundation to support the proposed structure. Bearing Values A bearing value of 1,500 p.s.f. may be used. The footings should be at least 15 inches wide and a minimum of 18 and 24 inches deep for the interior and exterior footings. The footings must rest 12 inches into the firm bedrock. All footings excavation must be observed by the geologist. If necessary, the footings should be deepened to rest in bedrock. Footing Dimensions and Setbacks The above footing dimensions are in accordance with section 2907 (i) of the Los Angeles County Building Code and Table 29-A of the Uniform Building Code, 1982 edition. Footings shall be set back in accordance with the County of Los Angeles Building Code Section 2907.1 (c). Footings Setback From Descending Slope Surface Footings on or adjacent to slope surface shall be founded in firm material with an embedment and setback from the slope surface sufficient to provide vertical and lateral support for the footing without detrimental settlement. Except as provided for in this section, the following setback is deemed adequate to meet the criteria. Footings shall be placed into firm material and located a distance of 1/3 the vertical height of the slope with a minimum of 5 feet and a maximum of 40 feet measured horizontally from the slope surface to the lower edge of the footing. Where the slope is steeper than one vertical to one horizontal, the required setback shall be measured from an imaginary plane 45 degrees to the horizontal is projected upward from the toe of the slope. Settlement - Total and Differential Based on the design criteria, settlement should be minimal when footings are founded on bedrock. Overall differential settlement is expected to be negligible. Approximately 1/2 of the settlement will occur during the construction period. Once constructed, the differential settlement should be insignificant. 5 GEO-ETKA, INC. JOB NO: FG-2578-86 Earth Pressures Lateral loads will be resisted by the friction between the floor slab and subgrade as well as the passive resistance of the soils against footings. A coefficient of friction of 0.35 may be used between slabs, footings and subgrade. The passive resistance of the soil may be taken to be 220 p.c.f. of E.F.D. . The active lateral soil pressure may taken as 45 p.c.f. of E.F.D. Active pressure must be adjusted for a sloping surcharge as per the applicable building code values. Expansive Soil Criteria Continuous footings should be reinforced with at least 1, Number 4 bar at the top and 1 at the bottom. Due to the expansive nature of the foundation soils, it is recommended that the slabs on grade be reinforced with Number 3 bars at 18 inches on center. This should be underlain by a moisture barrier. The moisture barrier should consist of 6 inches of clean, uniform sized, crushed rock or clean coarse sand. Also, a 6 mil poly vinyl chloride sheet or comparable impervious material on top of it may be utilized as additional protection.- All joints shall be made so as to preserve the impervious character. The membrane should be protected from puncture by a cushion of at least 3 inches of sand, above and below the plastic sheet. The above criteria are based on the assumption that the moisture barrier is installed and the concrete placed before the soil has begun to show significant surface cracks. Should such cracks occur, the soil should be thoroughly wetted to a depth of 18 inches so that all cracks have disappeared. This should occur 24 to 48 hours prior to placement of the concrete itself. This is in accordance with the County of Los Angeles Building Code Section Code Section 2907 (1). 6 GEO-ETKA, INC. JOB NO: FG-2578-86 General Drainage Recommendations In view of the expansive nature of the on site soil, as in any good design, positive drainage should be designed, i.e. all external water such as rain, irrigation, and water generated from washing the walkways should be drained away from the structure. A berm should be placed on top of the slope to control water from going down the slopes. Roof gutters should be provided. The water collected and drained to the street. Water proofing the exterior footing area in contact with planters should also be considered for added protection. Plants and trees planted should be chosen selectively, such that they consume least amount of water. A horticulturist may be consulted for specific recommendations regarding plant type, etc. . As an alternate to the above, water drainage can be to the streets by means of energy dissipation devices. Drainage system utilized should be detailed on the plans. Section 309 Statement Based on our evaluation, the findings presented and the recommendation made of the subject lot with respect to Section 309 of the County of Los Angeles, the site will be geologically stable. No geologic hazards are present nor will the grading affect the site or the stability of the proposed house and the off site property. Demolition Special note should be taken during the any demolition of the existing buildings so as to locate all underground items, e.g. pipe, conduit, storage tanks, septic tanks, cesspools or leaching lines, water wells, irrigation pipe, etc. . Any septic tank found should be removed from the site. Any seepage pit or cesspool found shall be pumped dry and filled with clean sand. The top and sides should be broken and removed if they are within 5 feet of finished grade. The water well shall be cut off and capped, 5 feet below finished grade. 7 GEO-ETKA, INC. JOB NO: FG-2578-86 Demolition (cont'd) Any metal pipe with a diameter greater than 1 inch shall be excavated and cleared from the site. Any vitrified clay leaching lines may be broken in place. Any tree that has to be removed due to the construction, should be completely removed and the cavity backfilled as described in grading section. Any root with a diameter greater than 1 inch shall be excavated and cleared from the site or mulched for future landscaping use. All cavities should be cut in a "V" shape so that compaction equipment will not bridge during grading which should be conducted in the manner noted below. It is recommended that the demolition be observed so as to prevent debris from remaining on or being buried on site. The demolition of the below grade items such as pipes and tree root systems must be checked by the soil engineer or his representative. Grading Prior to the controlled grading operations, the construction area should be stripped of all vegetation that is present and the debris removed from the site. If area of the existing fill is to be utilized for structural support, all fill must be removed to firm soil. A moderate amount of grading is anticipated in the development of this site. It is recommended that all surface which is loose that will support floor slabs or asphalt concrete paving, and all surface which will receive fill or backfill, be scarified to a depth of 8 inches, watered or dried to near Optimum Moisture Content and recompacted to a minimum of 90%. Where fill or backfill is required, it should be placed in a maximum of 6 inch loose layers and each layer compacted at near Optimum Moisture Content to at least 90% compaction. Clean on site soils may be utilized as fill material. Imported fill soil should be predominantly granular, non -expansive and capable of developing the bearing strength required for the project. 8 GEO-ETKA, INC. JOB NO: FG-2578-86 Grading (cont'd) Note that the size of fill material shall not be greater than 2 inch in diameter or length. In the parking area, the base soil should be placed and compacted to at least 95% of the compaction standard. The asphalt should be compacted to at least 96% of its maximum density. The asphalt used should be AR 4000 or AR 8000 or equivalent. The baserock should be Class II California Specifications or equivalent. Compaction Standard: A.S.T.M. D-1557-82 If required by the approving agency, Expansion Index Test (U.B.C. 29-2) will be run at the time of rough grading. A grading and a foundation plan should be submitted to this office prior to starting the grading. A pre -grade meeting is recommended. In order for us to provide better service, a minimum of 48 hours notice should be provided to schedule or cancel any geotechnical work. GEO-ETKA, INC. should be retained to observe all grading operation and the required testing of the utility trench backfill as well as to observe the footing excavations. If conditions are encountered during the design, approval by the governing agencies, and/or the construction period that appear to be contrary to the findings of this report, this office must be notified so that proper modifications may be made. Respectfully submitted, Geo-Etka, Inc. Ghayas A. Khan, P E. Civil Engineer, C- 8344 Expires 03-31-89 Ahmed Ali President GAK/AA/pka 9 2000 1900 1800 1700 1600 1500 1400 • 1300 W 1200 1100 A ! 1000 0 a 900 • 800 H W700 • 600 500 H 400 U) DIRECT SHEAR TEST ATrench 1 @ 1' Trench 3 @ 4' 300 200 100 GEO-ETKA, Inc. Job Number: FG 2578-86 17 a!- O 0 0 0 0 0 0 0 O 0 0 0 0 0 0 0 0 0 O O 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 H N C1 ul "O N- CO ON 0 H N C) u \ "D N- CO H H H H H H HHH SURCHARGE PRESSURE, POUNDS PER SQUARE FOOT Plate "A" GEO-ETKA, Inc. Job Number: FG-2578-86 TRENCH ONE AT ONE FOOT CONSOLIDATION TEST DATA 0.0000 0.0050 0.0100 0 w cr) 0.0150 0 H 0.0200 z 0 E1 A H 0.0250 0 0 0.0300 0.0350 . 0 0 0 0 LOAD, (KIPS PER SQUARE FOOT) 0 0 0 -1- ao \o ri Plate "C" CONSOLIDATION (IN 0.0000 0.0080 0.0160 XER ADDED 0.0240 0.0320 0.0400 0.0480 0.0560 O GEO-ETKA, Inc. Job Number: FG-2578-86 TRENCH THREE AT FOUR I'1' CONSOLIDATION TEST DATA O O. 0 O. O. 0 �-I N - LOAD, (KIPS PER SQUARE FOOT) Plate "C" COARSE GRAINED SOILS MORE THAN 50% LARGER THAN # 200 SIEVE FINE GRAINED SOILS MORE THAN 50% PASSING # 200 SIEVE SOIL CLASSIFICATION CHART MAJOR ..DIVISIONS' GRAVEL AND GRAVELLY SOILS LESS THAN 50% PASS #4 SAND AND SANDY SOILS MORE THAN 50% PASS #4 SILTS AND CLAYS SILTS AND CLAYS CLEAN GRAVELS GRAVELS WITH FINES CLEAN SAND SAND WITH FINES L.L. LESS THAN 50 L.L. GREATER THAN 50 HIGHLY ORGANIC SOILS GRAPH ( LETTER 5YMi,1 SYM.. SOIL SAMPLER • FOR UNDISTURBED SAMPLING CONNECTING SLEEVE GW GP GM GC SW SP SM SC ML CL OL MH CH OH PT YPICAL DESCRIPTION WELL GRADED GRAVEL AND SAND POORLY GRADED (TRAWLS SILTY GRAVELS CLAYEY GRAVELS WELL GRADED SAND NO FINES POORLY GRADED aND NP TE SILTY SANDS CLAYEY SANDS INORGANIC SILTS INORGANIC CLAYS • ORGANIC SILTS INORGANIC SILTS INORGANIC CLAYS ORGANIC CLAYS PEAT, HUMUS BRASS TUBING 2.625 INCHES I. i//////////////////,.>•• • • •• • •••.• • BALL VALVE ETKA, Inc. CUTTING EDGE Appendix I C180--tTKA, fl C. LIMITATIONS 1. This Geotechnical Report is based upon data obtained by surface reconnaissance, test borings, laboratory test results, preliminary engineering analysis, and the necessary review of geologic maps and literature pertinent to the site. No inference should be drawn from the language of the report that the scope of the investigation was any wider. It must be understood that although the observed and reported conditions are considered representative, local variations of geologic and/or soil conditions may exist for which this firm cannot assume responsibility. This report was prepared upon your request for our services, and in accordance with accepted standards of professional practice. 2. This report is issued with the understanding that it is the responsibility of the owner or of his representatives to ensure that the information and recommendations contained herein are called to the attention of the developer and his architect and engineers for this property so that necessary steps are taken to implement the recommendations of this report. 3. The findings of this report are valid as of the present date. However, changes in the conditions of a property can occur with the passage of time, whether they be due to natural processes or to the works of man, on this or adjacent properties. In addition, changes in applicable or appropriate standards occur, whether they result from legislation or the broadening of knowledge. Accord- ingly, the findings of this report may be invalidated, wholly or partially, by changes outside of our control. Therefore, this report is subject to review and should not be relied upon after a period of two (2) years. Appendix II GEO-ETKA, INC. ESTABLISHED 1965 FOUNDATION SOIL INVESTIGATION. ENGINEERING GEOLOGY PAVEMENT DESIGN. SLOPE STABILITY ANALYSIS COMPACTION CONTROL. PERCOLATION STUDIES MATERIAL INSPECTION AND TESTING FULLERTON BUSINESS CENTER 17141 870.0800 2524 EAST FENDER AVENUE • SUITE C • FULLERTON. CA 92631 APPENDIX III ENGINEERING NG GEOLOGIC INVESTIGATION AT No. 7 Williamsburg Lane Rolling Hills California FOR Mr. and Mrs. Charles Thornton No. 7 Williamsburg Lane Rolling Hills California 90274 BY Richard D. Merker, CEG 469 Consulting Geologist 2115 North Ross Street Santa Ana, (' 1 ifornia 92705 714-542-0732 May 29, 1986 Job No: FG-2578-86 GEO-ETKA, Inc. .. Job No: FG-2578-86 This report presents the Geology and Engineering Geology of multi - sided large lot measuring, in maximum dimension ± 300 feet East- West by ± 200 feet North -South and located at No. 7, Williamsburg Lane, Rolling Hills, California. The purpose of the investigation was to determine the foundation conditions and engineering geology for the proposed additions of a guest house, to be located at the Southeast end of the existing house, and a curved retaining wall to be located at the top of a 1:1 (H:V) slope on the Western portion of the property. Construction plans were not available at the time of writing this report, but it is believed the guest house will be of similar single story frame construction, as the existing residence. The area where the proposed guest house is to be located is essentially flat. Most of the ground above the proposed retaining wall addition slopes gently down towards the West. At the bottom of the above 50'± foot high 1:1 (H:V) slope there is a Southerly flowing drainage, which was dry at the time of this investigation. The proposed guest house area is planted with lawn grass and most of the retaining wall area has a thin to heavy growth of brush and small to large trees. The site was investigated by means of three backhoe dug, soil sampled, geologically mapped test pits; one in the guest house area and two in the vicinity of the proposed retaining wall. -1- GEO-ETKA, Inc. Job No: FG-2578-86 Earth Materials Underlying the entire site and found in every test pit at a depth of four and one half feet, is a white to tan, moist to damp, stiff to very hard, mostly massive, very locally bedded, weathered diatomaceous siltstone without joint fractures and few other fractures. Excepting very locally, on the slope, all of the bedrock, on the site is overlain by stiff clayey sandy silt and compact sandy silt colluvium soil cover. All of the colluvium, below ± 6'°inches, is quite competent. Only found very locally, at test pit two, is sandy silt with debris, which is expected to be construction derived from the very close proximity of the large stables. There is no evidence that this artificial man -placed fill extends any distance beyond test pit two. For a complete description of the earth materials, please refer to the three test pit logs and please refer to site plan geologic map for the distribution of the earth material. Comments and Recommendations In the guest house area,it is judged, both the colluvium and bedrock would provide good foundations. On, and/or directly above a steep slope, bedrock is the preferred foundation -material. Please refer to the GEO-ETKA Soils Engineering Report for all foundation recommendations. The Geologist should inspect all bedrock foundation excavations. Following construction all unprotected areas should be planted with suitable landscape planting. -2- GEO-ETKA, Inc. .. Job No: FG-2578-86 Comments and Recommendations (cont'd) Only very locally were bedding planes found and these were oriented favorable for good bedrock slope stability. Section 309 Statement Based on our evaluation of the subject lots with respect to Section 309, of the Los Angeles County Building Code, the site will be geologically stable. No geologic hazards are present, nor will the grading affect the site or the stability of the proposed residence or the off site property. If there are any questions, please feel free to contact this office. Respectfully submitted, GEO-ETKA, Inc. ichard erthr M, CEG-469 Consulting Geologist RDM/mm EQUIPMENT USED; 24" Backhoe ELEVATION: GR.D SUR. LOGGED BY: RDM r ' GROUNDWATER:- No GWS PIT SIZE:=X FIELD WORK:; 2/°!.66 SAMPLE op: ® 0 A. " x 27.9 70.6 — x 27.5 77.3-4 x 25.3 80.1 _ 0 0 m • .0 0 s- H u j +Raaund Hooter. G0004bel 2115 North Ross ' 'T.�:, �.: Santa Ana.�Ca 2706 O (714) 5 2-0732 . Z 5101 OW. E. E. grol DETAILED DESCRIPTION PI Ta}"(COLOR•MOISTURE•CONSISTENCY•ETC) N Brown, moist, soft to stiff, clayey sandy silt, QSW Light yellow, moist to damp, stiff to hard, massive, diatomaceous, siltstone TMA •SIDE VIEW SKETCH• • LOG OF TEST PIT N05,GE_gro6 RT PATE 1S OF3 FIGURE NO. A— 1 pe C� y . 0 41 O $'m co C �\ Q "chord Mortar. Colik54 2115 North Ross s.nte Alm. COL n6.- s�` ' (714) 5Q.0732 .. Z F EQUIPMENT ,USED; 24" Backhoe 1 ELEVATION: "1 87 I LOGGED. BY: RDM GROUNDWATER:' .NO (Wb ' • PIT SIZE:` 2'_x_= FIELD :WORK:'S2 8 az SAMPLE I: s A 9 08 i ,. W - 2 d Z a o DETAILED DESCRIPTION PUT T 4 IC... ail ® a a a.'8• �" ' c., sv�r-*N(COLOR•MOISTURE•CONSISTENCY•ETC) NO. 2( • MEM Tan, white and brown, damp, loose and soft, sandy silt and silty sand with bricks and chunks of concrete and other debris, AF, Artificial man -placed fill Light tan, damp, hard to very hard, locally.' bedded, locally massive, no joint fractures, numerous iron oxide stains,\(with some loose blocks of very hard not -in -place siliceous siltstone), all underlain by the above described diatomaceous siltstone, Beddingplane attitude @E.W.75°N to vertical.@ 71 TMA 4 TMA I •SIDE VIEW SKETCH• • LOG OF TEST PIT riFoleg4.1y6PORT DATE7140 FIGURE A-NU1• EQUIPMENT USED: 24'" Backhoe ELEVATION: GRD SUR I LOGGED BY; RDM GROUNDWATER:l , ". PIT SIZE: ' X14 I I FIELD WORK: lb -aAmELL. I.: • u: _ IC W lc CC � Cr • I:Z a x 71.5 43.3 4 . 5 , J. - 7' IMMO .10 sm DETAILED DESCRIPTION P I T (COLOR. MOISTURE•CONSISTENCY•ETC=h J. Brown, moist, loose to compact, sandy silt with scattered cobbles, QSW White to light tan, damp, compact to very hard, massive, few fractures partly diatomaceous siltstone.-nmh EOM MEW - MIM Board. Fence 1 nisi North Roes ' Santa Ana. WM 82706- •SIDE VIEW SKETCH• .4 LOG OF TEST PIT FIGURE N O. roycf_g*FtrbP0 RT SATE ' OF T3 A- 1 GEO-ETKA, INC. ESTABLISHED 1965 FOUNDATION SOIL INVESTIGATION. ENGINEERING GEOLOGY PAVEMENT DESIGN, SLOPE STABILITY ANALYSIS COMPACTION CONTROL. PERCOLATION STUDIES MATERIAL INSPECTION AND TESTING FULLERTON BUSINESS CENTER 17141 670.9800 2524 EAST FENDER AVENUE • SUITE C • FULLERTON. CA 92631 Mr. and Mrs. Charles Thornton No. 7 Williamsburg Lane Rolling Hills, California 90274 INVOICE ENGINEERING SERVICES DATE: May 29, 1986 INVOICE NO.: 5976 JOB NO.: FG-2578-86 Foundation Soils Investigation and Engineering Geologic Investigation at No. 7 Williamsburg Lane, Rolling Hills, California $1,675.00 INVOICES ARE FOR ENGINEERING SERVICES AND ARE DUE ON PRESENTATION. THANK YOU. Interest of .833% plus a service charge of $3.50 per month will be charged on put due accounts.