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Home My WebLink About; La Costa Meadows Lot 719; Soils Report; 1986-08-25J. H. KLEINFELDER8ASSOCIATES GEOTECHNlCAUENVlRONMENlAL CONSULTANTS . MATERIALSTESTING 0111 cwI)cuoNI MESA BLVD.. SE s SW DIECO. CA92‘1. ~,D)~41-!1.6 Cheryl Barnes 2433 Summerhill Drive Encinitas, California 92024 August 25, 1996 51-1102-l - .~ - - - - susJRcT: GECTECRNICAL INVRSTIGATION LA COSTA NEADOWS - LOT 719 ARGCNAUTA UAY, LA COSTA, CALIFORNIA In accordance with your reguest we have completed a geotechnical evaiuaticn at the subject property. The attached report presents the results of our investigation and findings as well as our opinions, conclusions, and recommendations. Should you have any questions regarding this report, please do not hesiatate to contact us. We sincerely appreciate the opportunity to have been of service. Respectfully, J.B. RIRINFRLDRR & ASSOCIATES Gerald J. Salontai ‘ Principal R.C.E. No. 29662 Distribution: (6) Addressee GJS:dt ENGINEERING DEPT. LIBRARY City of Carlsbad 2075 Las Palmas Drive Carisbad CA92009-4859 @piW 3/31/~7 J. H KLEINFELDER & ASSOCIATES 51-1102-I Page 2 -. - - - - - I. INTRODLJCTION A. Product Description This report presents the results of our geotechnical investigation of Lot 719 of La Costa Meadows Subdivision, La costa, California. The approximate location of the site is showr. on the Vicinity Map, Plate 1. A single-family residence will by constructed on the subject property. The residence vii; be e one- or two-story wood-frame and stucco structure with a concrete flocr slab-on-grade. We understand that cuts and fills on the order of 5 feet will be made in order to achieve final f:-;c.- _,I&-... grade. B. Purpose and Scope of Work The purpose of this investigation is to evaluate the feasib,ilitj of the proposed development with respect to the subslArface conditions, and to provide opinions and recommendations concerr.ing the following: 0 Soils criteria for foundation design, including allowable bearing pressures, passive soil resistance to lateral loads, and anticipated settlements: 0 Criteria for preparation of subgrade, concrete, floor slabs- on-grade: 0 The presence of geologic hazards, if any; and, 0 Site preparation and grading. The scope of our services included the following: Review of available pertinent data including geologic raps, aerial photographs, and subdivision grading plans. Site reconnaissance and mapping of the sl&ject property. Excavation of three shallow test pits to evaluate on-site soil types and depth to bedrock material. Laboratory testing and analysis of representative soil samples. kzalysis of compiled data. Preparation of this report presenting our findings and conclusions regarding the subject site. J. H. KLEINFELDER & ASSOCIATES 51-1102-l Page 3 - - - -~ C. Authorization Authorization to proceed with our work on this project was given by Ms. Cheryl Barnes in the form of signature to our Agreement dated July 17, 1986. II. INVRSTIGATIVR WETRODS A. Field Exploration Our subsurface exploration consisted of the excavation by hand of three shallow test pits on August 1, 1986. The test pits were excavated to depths up to 3 feet below the existing ground surface and were logged by a geologist. The test pits could not be advanced beyond 3 feet due to refusal in the underlying bedrock. The approximate locations of the test pits are shown on the Site Plan, Plate 2. Soil conditions encountered in the test pits are shown on the test pit logs, Plates 3 through 5. A copy of the Unified Soil Classification System used to identify the site soils and a Key to the Logs is presented on Plate 6. B. Iaboratory Testinq Our laboratory testing program consisted of tests for maximum density-optimum moisture relationship and swell tests. Results of these laboratory tests are shown on Plates 7 through 9. III. DISCUSSION, CONCIUSIONS AND RRCOWWRNDATIONS A. Discussion 1. Site Conditions The subject property is Lot 719 of the La Costa Meadows Unit 4 development, in the City of Carlsbad, California. The lot is located on the west side of Argonauta Way near the inter6ection vith Luciernaga Way. The lot is bounded on the north and west by residences, and on the south by an empty lot. The present site topography slopes gently towards the southwest and ranges in elevation from 420 to 440 feet mean sea level (MSL). It does not appear that any significant grading has altered the natural topography of the lot. Vegetation consist8 of low-lying weeds and shrubs, and one large eucalyptus tree in the southeast corner. i-m-l J. H. KLEINFELDER 81 ASSOCIATES 51-1102-l Page 4 -~ - - - - - - A dirt road (trail) crosses the central portion of the lot. Several piles of debris and undocumented fill were noted on the lot which appear to have been dumped from an off-site source. 2. Subsurface Conditions Our subsurface investigation indicates that the lot is underlain by the Santiago Peak Volcanics (bedrock) which is locally overlain by a thin layer (2 to 3 feet) of topsoil and/or residual clay. Where encountered, the bedrock is highly weathered and fractured, with red clay infilling the fractures. The topsoil was encountered at higher relative elevations on the lot, andconsistedofreddishbrown,drytodamp, loose to medium dense, fine to coarse clayey sands, with abundant fragments of the bedrock. The expansion index of the topsoil sampled was 64 vhich indicates a medium potential for expansion, per the Uniform Building Code (UBC) Method 29-2. Residual clays wre encountered at lower relative elevations on the lot, and consist of dark reddish brown, damp, stiff sandy clay. Where sampled, the expansion index for this material was 117, which indicates a high potential for expansion. Our visual site reconnaissance and mapping indicate that the majority of the lot is underlain at the surface by topsoil developed on the Santiago Peak Volcanics. We estimate that the depth of the topsoil varies across the lot, and ranges from 0 to 3 feet. Several scattered outcrops of the weathered bedrock were noted on the lot. B. Conclusions Based on the results of our preliminary investigation, we feel the site can be developed for its intended use from a soils engineering standpoint. However, a major consideration in design and construction is the presence of moderately to highly expansive clays. These expansive soils on the site are subject to considerable volume changes with changes in soil moisture content. Changes in soil moisture content occur as a result of seasonal precipitation, irrigation of lawns and landscaping, breaking water and sewer lines, etc. Changes in volume of the soils can cause differential heave of building foundations, floor slabs, exterior concrete flatwork, and driveway pavements. Several methods are availabletobeusedtoreducethe effectsof the existing expansive soils. These include: ,A. Excavation of the site soils and replacement at elevated moisture contents and reduced density. 1 &X I J. H. KLEINFELDER & ASSOCIATES 51-1102-l Page 5 - - - - - - - B. Removal of the expansive soils from structural areas and replacement with non-expansive fill. C. Supporting the structures on highly reinforced foundations founded on clay soil at depths below which significant variations in soil moisture can be expected. Our recommendations are presented to minimize the effects of expansive soils by reinforcement of foundations and slabs-on- grade (Method C, above). The clays vary from moderately to highly expansive at the site. We have therefore included recommendations for highly expansive soils in this report for pre-planning purposes. Additional samples should be taken during grading and expansion tests should be performed to evaluate that the expansion potential of the soils which are present beneath foundations and slabs (at finish grade). Modifications will be made to our recommendations at the completion of grading, if necessary. C. Recommendations 1. Earthwork and Site Preparation Although no grading plan was available at the time this report was prepared, we understandthatupto 5 feetofcutand fillmay be necessary to achieve the desired finish grade for the building pad. ,Prior to grading, the site should be cleared of surface and subsurface obstructions including any existing debris and stripped of vegetation. Removed vegetation and debris should be disposed of off-site or in a non-structural fill or open space area approved by the geotechnical consultant. Removed vegetation can be stockpiled and utilized as mulch for slope cover. Boles resulting from removal of buried obstructions which extend below finished site grades should be replaced with suitable fill material. In areas to receive fill, the upper 12 inches of existing soil should be scarified, moisture conditioned to a minimum of 4% above optimum moisture and replaced at a relative compaction between 85% and 90%, in accordance with ASTM D1551-78. ThiS treatment should also be performed in cut and transition areas such that moisture conditioned compacted soils extend to a depth of 36 inches below finish pad grade. A representative from our firm should be present during the removal and replacement to observe that the above is accomplished. Any import soils ehould be predominantly granular, non-expansive, and tested for suitability by the geotechnical engineer. .~L ,,-,, ~.V. ; .: - _ 1. H. KLEINFELDER &ASSOCIATES - - - - - - - - - 51-1102-l Page 6 On-site native soils should be suitable fsr structural fill provided that the moisture conditioning and ccnpaction procedures listed above are followed. All structural fill should be moisture conditioned, placed in a lift thick!!ess not exceeding 9 inches, and compacted between 05% to 90% relative compaction in accordance with ASTM D1557 Compaction Test PlezLod. Fills placed on soils steeper than 5 horizontal to 1 vertical shall be keyed into firm natural soils or rock by a series of benches. The procedures for placement of fil; on sloping ground is described in Appendix A of this report. 2. Removal of Compressible Soils In general, all topsoils, alluvial/colluviel soils, and any undocumented fill soils not removed by the planned grading should be excavated, moisture conditioned, and the: compacted prior to placing any additional fill. Typically, the reaidual (topsoils), alluvial, and colluvial soils that occur on size are compressible in their present state and may settle ap&reciably under the surcharge of fills or foundation loadings. In areas that will receive fill or other surface improvements, these soils should be removed down to competent materials and recompacted. Residual/topsoils and undocumented fill soils across the site are on the order of 0 to 5 feet thick. These deFr?.s may be modified based on geotechnical observation during grafing. 3. Excavations Shallow excavations (4 feet or less) at the project site can be readily excavated by conventional constructic.? equipment in good operating condition. Because the test pits made for this investigation were excavated by hand, we car.r.ot comment on the ease of excavation below depths of 3 to 4 feet. When using earthwork equipment, excavations that extent deeper than 4 feet below the existing ground surface may reF:ire blasting. The evaluations of the excavatability of the unEarlying bedrock was not within the scope of our work. We shou;l? be consulted on a more specific basis for the evaluation of :he rippability of bedrock. 4. Foundations We feel that conventional continuous foundatizs will be suitable for support of the proposed structures. Zowever, increased reinforcement and embedment depths will be necessary to resist the expansion pressures associated with the m-site clays and to provide a barrier to fluctuations in soil moisture content beneath concrete slabs. All exterior foundations should be founded at least 24 inches below the lowest adjacent exterior - - J. H. KLEINFELDER 8, ASSOCIATES - 51-1102-l Page 7 -. finish grade. Interior foundations should be founded a minimum of 18 inches below grade. All foundations should be continuous and structurally tied together, including across all openings, such as garages. The use of isolated foundations should be avoided. All foundations should have a minimum width of 12 inches. - Foundation reinforcement should consist of four No. 4 b&r-s, two placed near the top and two near the bottom. This reinforcement should not preclude requirements set forth by the structural engineer. Foundations should be sized to impose a minimum - bearing pressure of 650 psf for dead loads. Foundations can be designed to impose maximum allowable net soil bearing pressure of 1500 pounds per square foot for dead plus long term live loads. - Allowable soil bearing pressures may be increased by one third for total load including wind and seismic forces. Passive soil resistance to lateral footing pressures may be calculated using - the equivalent fluid weight of 250 pounds per cubic foot or a base coefficient of friction of 0.30. 5. Concrete Slab-on-Grade Floors - As discussed in Section 1 above, the soils beneath the floor slab should be excavated to a depth of at least 36 inches below the - bottom of the slab and placed in maximum 8-inch lifts to 85% to 90% of the maximum soil density in accordance with ASTM D1557-78. The soil moisture content should be adjusted to 4% above optimum - moisture and remain at this moisture content up until the time concrete is placed. The thickness of the moisture conditioned and recompacted clay soils should be uniform under the entire structure. - Structural separation of the slabs from the foundations should be provided to permit vertical movement of the slab. ~Provisions of - movement of at least l/2 inch should be provided. Concrete slabs should be a minimum of 5 inches in thickness and should be reinforced. The purpose of reinforcement is to minimise breakage - of the slab, not to resist movement from expansive soils. Reinforcement should consist of: (1) No. 3 reinforcing bar6 placed 18 inches on center in both directions at mid-height in the slab or; (2) W5.8 x W2.9 Davis Walker Econolap fabric placed - at mid-height; or, (3) 6 X 6-6/6 wire mesh placed at mid-height. These recommendations are given in order of preference fror a soils engineering standpoint. If the wire mSSh is proposed for use, we strongly recommend that great care be taken so that the mesh is placed at mid-height in the slab. Misplacing of the mesh would result in insufficient reinforcement which could result in breakage of the slabs if the clays swell as anticipated. - J. H. KLEINFELDER & ASSOCIATES 51-1102-l Page 8 - - - - - - - - - Floor slabs should be underlain by a minimum of 4 inches of free- draining gravel or coarse sand to reduce the effects of swelling and to act as a capillary moisture break. We would further recommend the use of a moisture barrier, such as visqueen, over the gravel. A minimum of 2 inches of sand shculd be placed over the barrier to facilitate concrete curing. 6. Exterior Concrete Flatwork Exterior concrete flatwork should be placed over a minimum of 4 inches of crushed gravel base. The soil subgrade beneath the base should be moisture conditioned in the upper 12 inches to a minimum of 5% over the optimum moisture content of the soil. Provisions for movement (expansion joints) should be made in the flatwork at maximum intervals of 10 fee:. Reinforcement consisting of 6 X 6-6/6 wire mesh is recommended in the flatwork placed as suggested in Section 5. 7. Settlement/Swell We estimate the total post-construction settlement/swell for foundations and slabs constructed in accordance with the above recommendations be on the order of one inch. Post-construction differential settlement/swell should be on the order of l/2 inch. 8. Additional Provisions for Utility Lines, Planters, and Drainage Because of the presence of expansive soils, special provisions should be made to prevent ground saturation of broken water lines, landscape overwatering, or improper site drainage. Water and sewer lines should include flexible connections where lines pass into buildings. Planters adjacent to buildings should be avoided. If planters are placed adjacent to b>uildings, they should have an impermeable liner to prevent water migration toward buildings. Roof gutters and site grading should divert drainage away from foundations. Maintenance Guidelines for Homeowners are presented in Appendix 5. IV. IJXITATIQNS A. Limitat ions The recommendations contained in this report are based on our field exploration, laboratory tests, and our untierstanding of the proposed construction. The soils data used in preparation of this report was obtained from the trenches made for this investigation. It is possible that variations in the soils could exist throughout the site. Therefore, if any soil conditions ere encountered et the site which ere different from those assumed in J. H. KLEINFELDER &.ASSOCIATES - 51-1102-l Page 9 - - .- - - - - - ,- the preparation of this report, our firm should be immediately notified so that we may review the situation and make supplementary recommendations. In addition, if the scope of the proposed construction, including the proposed loading or location of the structure changes from that described in this report, our firm should also be notified. This report has been prepared for the exclusive use of Ms. Cheryl Barnes in accordance with generally accepted soil end foundation engineering practices. No other warranty, expressed or implied, is made. B. Additional Services The recommendations made in this report are based on the assumption that en adequate program of tests and observations will be made during construction to assure coupliance with these recommendations. These tests and observations should include, but not necessarily be limited to the following: 0 Observation and testing during site preparation and grading and placement of any fills; 0 Observation of foundation excavtions; end, 0 Consultation as may be required during construction. Additional information concerning the cost of these services can be obtained from our office. We also recommend that the grading and foundation plans together with e copy of the specifications for this project be provided for our review prior to bidding. I RR1 - - - - - - / / T ,* \, \, \ \ i ,~’ ,. R4SE MAP: Aerii' Foto-Map Book 1985, PAGE 8E I. H. KLEINFELDER & ASSOCIATES -*-a cm6al-n . Llll., “9-z m - ;rm- -moam*ID.wmc.uNDlfm.cA~r I - f PROJEZ m. 51-1102-l ‘ SITE LOCATION MAP ;$N;;;LA COSTA LA COSTA MEADOWS PLATE 1 N t - - - - - - - - - - - - - - - LEGEKE ,,I:' LOCATIOi; OF DIRT ROAD .H. KLEINFELDER & ASSOCIATES SITE PLAN ~LO,L‘Lt*KAL c CsO"NDWllt‘ ~ONs"LI*"Ts BARNES.LA COSTA rtjf~! Number 5]-110;-1 PLATE Ii 2 I I I I I I I I I I I I I I LOGGED BY: DC DATE:]-Z&h EQ”,,,ME.,T: b’k,flUdl Excavation EL,EVATION:&jxuiuU I v 4’~ ’ PlSl LOCATION: Lot 8719, La Costa Meadows 3EOLOGIC 4TTlTUDES :IKREGULAR GEOLOGIC DESCRIPTION TOPWIL: u-l.45 Reddish brown, dr.y, loose to meciiulli dense, f-ine to codrse clayey sand. Approximately 3U:,, blocky rock fragments (Jsp) ~EATIIERED SANTIAGO PEAK VOLCANICS. ___- --.-- __ ,--. ~--- ___. 1.45-1.7'Ked-brown and greenish, highly frdcturcd, highly weathered fine gr~lined liIetdvOlctillic rocK. Cldy a~lteration alony frdcture plmcs. TOTAL DEPTH: 1.7' NO GKOUNO 1IATEK i!NCOUNTEKEO BACKFILLED: 7-23-W GRAPHIC LOGS‘y&‘, ! ;ALE: l”=l’ u SUF -Ta.’ f--Y; ,,-. .I. d”.‘,Q.i i& :, .+;. ._ y - ;J- -I 3’. ,a’ , IF1 T- hCE SLOP E: Topsoil Jsp I I SC 113 II-.! 20 l-l. _-___ ,. ~.~. = z Z- m* WV 0 L 1: - I I I I I I 1 I I I I I I I LOGGED BY: I)c DATE: 7-77-81; EL.EVATION: Amroxjmatelv 430 I~SI ' ', EQUIPMENT: m LOCATION: I nt ~1 719 I a Tnm 3EOLOQIC ATTITUDES GEOLOGIC DESCRIPTION --- --- -- ..--,-. - SIEATlli~~fW SANTIAGO PLAK VOL.CANICS: -mO--e.-2'e~ Red-brown dnd greeni s11 ti~iqhly fractured, hiyhly weathered fine yrdirled ilietavolcanic rock. TOTAL UEPTli NO GROUND W ii7 i3ACKFILLED: 7 .ii’ -ER ENCOUNTERED ‘-23-i)b GRAPHIC LOG ‘?t! sLi CALE:. I- / ACE SLOP _~_~__._ iEE??( - JSP ,lor.i ,& ---- LL - ~ I I I I I I I I I I I I I I I LOGGED BY: i DATE:L-~-66 EL.EVATION:~~KinLlf 47h II>1 -t .,c EQUIPMENT: iqalludl i~XCaVd.i.SXL LOCATlON:bL, f;llY. Id Cn<tc 14r~~~lrlnw< I QEOLOGIC ATTITUDES GEOLOGIC DESCRIPTION - c: IRREGuLA RESIDUAL CLAY: -_ O-2' Reddish brown, damp, stiff, fine to coarse sandy clay. Occasional roots and rootlets. Abundant blocky rock fragments. WEATilEKED SANTIAGO PLAK VOLCAIIICS: L-Z.Z'Ked- brown and greenish, highly fractured, highly weathered, fine grained metavolcanic rock. ation along fracture planes. Clay alter- TOTAL DEPTH: 2.2' 140 GROWD ilATER ENCOti;4TERED BACKFILLED: 7-23-&j Topsoil JSP GRAPI CALL:. _..~~ __ ACE SLOPE: tinrimn . :L 1e I-.! 2@ i-l .;y - TREI - - - - - - - - - - - - UNIFIED SOIL CLASSIFICATION SYSTEM I.H. KLEINFELDER & ASSOCIATES :fmtEIIHIC*L CoNs"LI*NI* . MAI111ALS 1II!INc ‘REPARED BY: DATE : TRENCH.#j&&EGEND BARNES/LA COSTA PLATE 1 I 6 - - - - - EXPANSION INDEX TEST RESULTS SA!VLE USCS INITIAL DRY FINGL EXPANSION LOCATION CLASS. MOISTURE: D ENSITY(pcfQ M'SISTURE ;~ EXPANSION INDEX RATING T-l il [d 11-2 SC 14.3 95.3 32.5 i / 64 medium T-3 -'3 @ I l'-2' CL 13.5 96.9 35.6 ; 117 high , * NOTE * Tests performed in accordance with UBC 29-2 PLATE I H L;EI%FCLDCR 6 ASSOCIATES BARNES/ LA COSTA 7 c.'!‘(‘I...'., (*,":,A*', . vrl,.,..! I,SlmL P.?OJECT NO. 51-1102-01 - - - - - - - - - - - - - - Barnes/ La Costa 51-llGL’-01 WATER CONTENT -PERCENT OF DRY WEIGHT - - - .- - - - - - - - - I WdTER CONTENT -PERCENT OF DRY V:I~‘<~~ - __“_ . _ .-_. ..- . ...“-. A,?.’ .lsnt I I I I “Fc-S;r- -,, r.F TFSTs1----- ‘~ ! n ,<;, , /%=.!&* j ‘It, ! I:#c- L,“L”, FT, 1!3,3 *.1*1* W111"T kILI\ 8 ',t to 10- COMPACCii:‘Li DIAGRAM lu”“C” D”OI 11N.1 * I. Dnw* I”, 51-t ,*, No lnrrr D “,“YW 1LOW P(D L/1(" 25 c**c ". :‘.! I Y J. H. KLEINFEiDi; AND ASSOCIATES .Lm.L" 0, LIIlll E 5 SO!! rr: i >.L!kLX EpyIDlrs - - - - - - - - - - - - APPENDIX A GENERAL EARTHUORK AND GRADING SPECIFICATIONS - I!. Earthwork Observation and Testing Prior to the commencement of grading. a qualified geotechnical consultant should be employed for the purpose of observing earthwork procedures and testing the filis for conformance with the recommendations of the geotech- nicai report and these specifications. The consultant is to provide adequate testing a:,d observation so that he may determine that the work was accom- plished as specified. It should be the responsibility of the contractor to assist the consultant and keep him apprised of work schedules and changes so that the consultant may schedule his personnel accordingly. - - The contractor is to provide adequate equipment and methods to accomplish the work in a:cordance with applicable grading codes or agency ordinances, these specifications, and the approved grading plans. If. in the opinion of the consultant, unsatisfactory conditions are resulting in a quality of work less than required in these specifications, the consultant may reject :r,e ticrk and recommend that construction be stopped until the conditions are rectified. I. General These specifications present general procedures and requriements for gracing and earthwork including preparation of areas to be filled, placement of fill, installation of subdrains, and excavations. The recommendations contained - in the geotechnical repor: are a part of the earthwork and grading speciiica- tions and should supersede the provisions contained herein in the case of conflict. Evaluations performed by the consultant during the course of - grading may result in new recommendations which could supersede these speci- fications or the recomr,endazions of the gcotechnical report. l%ximum dry density tests used to determine the degree of compaction should be performed in accordance with the American Society for Testing and tcaterials test methcd PWM D1557-78. Ii:. Preparation of Areas to be Filled 1. 2. 3. 4. - Clearinq and Grubbing: All brush, vegetation and debris shoiild be removeo and otherwise disposed of. Processino: The existing ground which is evaluated to be safisfactory for SuDpOrt of fill should be scarifye 7 d to a minimum depth of 6 inches. Existing ground which is not satisfactory shou?d be overexcavated as specified in the following section. Scarification shoulc continue until the soils are broken down and free of large clay lumps or clods and until the working surface is reasonably uniform and free of uneven features rhich would inhibit uniform compaction. Overexcavation: Soft, dry, spongy. or otherwise unsuitable ground, ex- tending to such a depth that surface processing cannot adequately im- prove the condition, should be overexcavated down to firm ground, approved by the consultant. Moisture Conditioning: Overexcavated and processed soils should be watered, dried-back, blended , and/or mixed, as necessary to attain a uniform moisture content near optimum. - - _- - - 5. Recmpaction: Overexcavated and processed soils k'hich have been Properly mixed and moisture-conditioned should be recompacted to a minimum relattve compaction of 90 percent. 6. Genchinq: Where fills are to be placed on ground v;;ith slopes steeper than 5:: (horizontal to vertical units), the ground should be benched. The lowest bench should be a minimum of 15 feet wide, be at least 2 feet deep, expose firm material, and be approved by the consultant. Other benches should be excavated in firm material for a minimum width of 4 feet. Ground sloping flatter than 5:l should be benched or otherwise overexcavated when considered necessary by the consultant. 7. f*c'Jr;ys.;: Ali areas to recfive fill, inc1udin.g pro.c2sifd areas, ren6:zl areas and toe-of-ffl! benches should be ap;rcved by the con- sult2'1: Friar to fill placement. IV. Fill material 1. General: Material to be placed as fill should be free of organic matter and other deleterious substances, and should be approved by the consultant. Soils of poor gradation, expansion, or strength characteristics should be placed in areas designated by the con- sultant or mixed with other soils until suitable to serve as satisfactory fill material. 2. Oversize: Oversize material defined as rock, or other irreducible material with a maximum dimension greater than 12 inches, should not be buried or placed in fills, unless the location, materials. and disposal methods are specifically approved by the consultant. Oversize disposal operations should be such that nesting of oversize material does not occur, and such that the oversize material is completely surrounded by compacted or densified fill. Oversize material should not be placed within 10 feet vertically of finish grade or within the range of future utilities or unoerground con- struction, unless specifically approved by the consultant. - 3. !mpcrr:: If importing of fill materiai is necessary for grading, the import material should be approved by the geotechnical consultant. v. Fill Placement arrd Compaction - 1. Fill Lifts: Appxved fill material should be placed in areas pre- pared to receive fill in near-horizonzal layer: ~3: exceeding 6 - inches in compacted thickness. The corsultani nay approve thicker lifts if testing indicates the grating procedures are sxh that adeqtiate compaction is being achieved with lifts of greater thickness. - Each layer sha?l be spread evenly and should be thoroughly mixed during spreading to attain uniformity of material and moisture in each layer. - - 2. Fill Moisture: Fill layers at a moisture content less than optimum should be watered and mixed, and wet fill layers shosld be aerated by scarification or blended with drier material. Moisture-conditioning and mixing of fill layers should continue until the fill material is at a uniform moisture content at or near optimum. 3. 4. 5. - - Compaction of Fill: After each layer has been evenly spread, moisture-conditioned, and mixed, it should bc uniformly compacted to not less than 90 percent of maximum dry density. Compaction equipment should be adequately sized and either specffically tie- signed for soil compaction or of proven reliability, to efficiently achieve the specified degree of compaction. Fill Slopes: Compacting of slopes should be accomplished, in addition to ncrmal compacting procedcres, sy backrcllic! of slopes with sheepsfoot rollers at frequent increments of 2 to .: feet .in fill elevzticn gain, or by other methods producin9 satisfactory results. At the completion of grading, the relative compaction of the slope out to the slope face shall be at least 90 percent. Compaction Testing: Field tests to check the fill moisture and degree of compaction will be performed by the consultant. The location and frequency of tests should be at the consultant's discretion. In general, the tests should be taken at an interval not exceeding 2 feet in vertical rise and/or 1,CK cubi: yards of embankment. - - VI. Subdrain installation - - - Subdrain systems, if required, should be installed in approved ground to conform to the approximate alignment and details shown on the plans or herein. The subdrain location or materials should not be changed or modified without the approval of the consultant. The consultant, hcwever, may recommend and upon approval, direct changes in subdrain line, grade or material. All subdrains should be surveyed for line and grade after installation and sufficient time allowed for the surveys, prior to commencement of filling over the subdrains. VII. Excavation Excavations and cut slopes should be examined during grading. If directed by the consultant, further excavation or overexcavation and re- fillfng of cut areas should be performed, and/or remedial grading of cut slopes performed. Where fillover-cut slopes are to be graded, unless otherwise approved, the cut portion of the slope should be made and approved by the consultant prior to placement of materials for consrruc- tion of the fill portion of the slope. - z’. - J. H. KLEINFELDER & ASSOCiATES - SENCHING DETAILS - - FILL SLOPE FILL-OVER :-CUT SLOPE To be cc.-sfrw!ed prior !D fill $.loEtmmt _-. SUEI LOWEST BENCH: Depth and width subject to field ciange based on consultant’s inspection. IRAINAGE: Eack drains rnoy be required ot the discretion of the geotechnicol consultant. NOTES. - 1. H. KLEINFELDER &ASSOCIATES 4 FINISHED GilADE - - - - - ALTERNATE A CCMPETENT f.!ATERlLL Cii EEDROCK ALTERNATE 8 1. 2. 5. 5. 6. 7. N”TES - &LL FlLL cis, EL i:PKS;EZ 8” Try s:+is %;luLER LED SUOULD BL i2e;::tJ i: L- LELLI 95: RE.ITIYt C:-iLCTI2h (ISTY. D ISjj-701. .??SE * 5*;.>3 CZ.>,S, OF cc*PP:Ttc S3,l F,LL DhL” ,rc “OCK F(IC.:-hTS i’;ci 6 :r:*z: I!, l.r.l,~J’ 0!.?1‘510\:. iZ‘.I L. :*;;:c .lZ’;‘i c m,u,cw TllltKNLIS CF !j FSFT t&j SYZYHJ. L.‘T Fl’l- IX-i*: j FE3 er,:, :n: :irfsjT i’T,ilT,. i::r, DLL::-I,T. :,t;a:r.; ci L=iz:I:. C4ibi.i” FILL. 32 F,LL p:L:I-:*.l S-I-L: EE :9*?,*‘...5LI ,hS?t:i[> f, ff-i ii:Ti.“.icAi L.Zie.Ci,. OVERSIZE ROCK DISPOSAL DETAIL - 1. H. #L.EINFELDER 8 ASSOCIATES - - - - FIPilSH GRADE SLOPE FACE ------ -.----.--- / _-__ -~_---__-----__--- ~~~-~--_-__--__-- ,G\‘ERSIZE..---- WI”‘““^‘“’ l”“~““” -- GRANULAR SOIL’ To fill voids, decsified by f iooding PROFiLE ALONG WINOROW --------- _---------- __----------- --- _-------___ _--- ------a-- OVERSIZE ROCK DISPOSAL DETAIL - j. H. KLEINFELDER &ASSOCIATES - - -. - SUBDRAIN DETAiL - SUEDRAIH PcrlO:aled Pi~e Surrounded Wllh ALTERhATE A: FlItor Materlaf Al!(l-cat, A-t 4” MIN. / ARemats A-2 FILTER MATERIAL Filter material Shall be Class 2 permeable material cer s:ate ot Cal!tcrnla Slarstard S;eclllcat!ovs. cr arcrove:! i!lernale C:aiS 2 graatng as fo1lov~~ SiE’JE S!ZE PERCENT PrSclFlG 1’ 105 3;A. so- lc”O 316’ hO-lCO No. 4 25.co PERFORATED PIPE 6” 0 MIN. i i - - - - / ! S.JEGQAM 1 112” Gravel Wrapped ~*LTEQHATE 9: In Fil!w Fabric / S”U!N. OVERLAP , I 9 ft. 3ft. i StiRDRAiI~I II.&TAlLLATI@:J - Subdroin pipe shall he instc!!ed ujith perforations c’ovv or. 01 lwotior,s desioncted by the ~eofechnicol c?~sultont, shall be ncxperforoted pipe. S’JB:3RAlt,J TYPE - Shirair! tvoe shall be AST!h CD3 Asbestos Cen:ent Pipe fA..C?l or ASTFA D2ij I? SIJR 23.5 or ASill DI 527. Sched~lr 40 Acryionitriie Dutcdiene qtyre?e fA8S) or ASTM D3034 SDR 23.5 or ASTM DIXS. Sc’hedule 40 Polyvinyl Chloride Plastic IP’JC) pipe or approved equivoleni. - j. H. K~LEINFELDER & ASSOCIATE~S - - TRANSITION LOT DETAILS NATURAL GROUND - -------~ -- .x F I L L .-_--.__-;-,,*~----~L ------ .-----z-c- - ---------c- -. cD,MPkCTEO ---_c-_- --_-- .c---. .---F---- -2-L _ --L---_& - ----,c,MO\; _R~ . I t __A__. .------c----------- _-----..- _--_-- 30” MII‘!. ,z.-----‘----T/.G-.- 7 \ OVEREXCAVATE AND RECOMPACT - - UNWEATHERED BEDROCK OR MATERIAL APPROVED BY E I--- THE GEOTECHNICAL CONSULTANT NOTE: Deeper nverexcovotion and recompaction shalt be performed if determined to be necessary by the geotechnicol consultant. - -’ - I.H.KLEINFELDER&ASSOCIATES - - - - - - - - - - SPECIFlCkTIONS FOR CLASS 2 PERMEABLE flATERIAL (CALTRANS SPECIFICATIONS) Sieve Size I" 314" 3/B" No. 4 No. 8 No. 30 No. 50 No. 200 X Passinq 100 9G- 100 40-100 25-40 1B-33 5-15 o-7 o-3 - Retaining k'ail Finishe? Grade Floor s lab i : / Soil Backfill, Ccnpacted to 90 percent relative density* 6" Oi~~et~r perforated Wall Footing filter rock beneath P'Pe 93 perce-t relative density* *Based on ASTM D1557- 82 l-m? J. H. KLEINFELDER &ASSOCIATES - - - -, - - Original GUT Iontir.gous subdrain at toe Class 2 perrrable Taterial to suitable outlet. " Kin. dia. d::roved perioratc SPECIFICATIONS FOR CLASS 2 PLWJIABLE I'JtTERIAL (CALTRAYS SPECIFICATICNS) Sirvc Sire 1 Parsing 1. 100 314’ 90-100 316’ 40-100 no. 4 25-40 NO. 8 lE-33 No. 10 s-15 No. so o-7 no. 2w O-3 --j 18" min. DRAINAGE OF FILL-SLOPE OR CUT-SLOPE IN SOIL ( NOT TO SCALE ) - 1. H. KLEINFELDER & ASSOC!ATES - - - - - REPLACEMENT FILL DETAIL SEE ALTERNATES A 6 F uB.O..‘,*kL.~ ..-.. -- --“--’ ------.-- ** ‘ I,.^.. ERNATE A f------ KEY MTH.--+ I, :E”i:armr , r’_*“‘. LCVL1. =-=! ~Ir~~.[CGw*tTLC ,,il ? ,:7 , I -~--;.. .___ L,+ - .-[- , c‘ ,<‘..‘I.~ ‘E.ET1 \ KDilNb . , L. .r:rci;i xc ,i2.~ L:~“Ea’09,Tr, Y, ,l.L / - iu’ DETAIL A-A’ :.,, I_ 7 f s : ~... ..- - ,)j t.ic-;;.et, t.-JcL. Ci!!. l:e;. Y :..".# oppf!. ore s,:?jf.cl !c !;c ;:<,: r( p,p:,/DionS. - :;tc, “nc .C’ chmqe. ,1*ro*‘:I: *,rt ‘y ?. ,.:;I:p[ 0 “~“.,~“q=-~ oi7LL’ *,=i ‘t.c”..i:,i>. CIPy ireI s,J5~+ro;ir.. blmke: rj.cc,, or ::.-rtlcoi drcin may be req..“*+< at thE - r’scrcticx? of the geatechnic=i coNU1:onl. Filler TP~IE’L~! ~Cil! 52 Class 2 pe-rw:~I~ rr.iteriai per Stat2 c1 CiiOo!?xa Standa: Sf2~11catb5nS. 0: 23crcv22 2:IErr,2ie. Class 2 ~*.2515; as lc!l3ws SIEVE SIZE PEFCEr;T FASSlli 1’ to3 314’ $“.:3” 3/E’ 4 ,z. , :’ ? FJ3. 4 25.4: No. E ih-33 NC. 33 NO. 53 No. 200 - S’XO?AI’! 1tJ5TA!J-ATIO(C - S&d-c% pipe shall be installed with perforatims dam or, at iacatim: designated by tihe geate,%ical consultant, shall be nonperforated pipe. 1 SV3DRAl’l T~YPE - $ubdraic, type s,%cl! be ASTM C508 Asbestos Cement Pipe (ACP) - or ASTM. D2751, Si>R 23.5 c~ ASTM 01527, Schedule 40 Acrylonitrile Sutadiene Stvme (ABS) or ASTM 03034 SDR 23.5 or ASTM Df785, ShedvIe 40 Polyvinyl Chloride P&tic - !?L’C) pipe or appraxd eqJ;voknt. - - - - .- - - - - - _- - - - - - - - 1. H. KLEINFELDER & ASSOCIATES SOIL - / 6" min:dia. approved perforated pipe (perforations down) \ / PERtdANENT DRAINAGE OF CUT-SLOPE IN ROCK ALTERNATE 1 ( NOT TO SCALE 1 ‘/ / ~ . w /: 6" min. dia. approved perforated pipe /- (perforations down) I ; ' \ / SPECIFICATIONS FOR CLASS 2 PEFXASLE MTLRIAL (CALTWiS SPECIFICATIONS) Sieve Size I Paring 1 DRAINAGE OF CUT-SLOPE IN ROCK ALTERNATE 2 ( NOT’TO SCALE ) :;,a 90-100 100 3/R’ 40-100 HO. 4 25-40 no. a 18-33 VI ,n 5.1s v Original GUT Continuous subdrain with Class 2 permeable materiaj-and perforafec' . y Original Gx'T subdraic. minim:. outlet. l--Km - - - APPENDIXB - - J. H. KLEINFELDER & ASSOCIATES __ MAINTJZNANCB GUIDELINES FORHOHROWNRRS - .- - - Homesites in general, and hillside lots in particular, need maintenance to continue to function and retain their value. Many homeowners are not aware of this and unknowingly allow deterioration of their property. In addition to suffering damage on his own property, the homeowner may be liable for damage occuring to neighboring properties as a result of his negligence. It is therefore improtant to familiarise homeowners with some guidelines for maintenance of their properties and make them aware of the importance of maintenance. - - - - - - - - Nature slowly wears away land, but human activities such as construction increase the rate of erosion 200, even 2,000 times that amount. When vegetation or other objects that hoid soil in place are removed, the soil is exposed to the action of wind and water greatly increasing the probability of erosion. The following maintenance guidelines are provided for the protection of the homeowner's investment, and should be employed throughout the year. A) Slopes, terraces, berms (ridges at crown of slopes), and proper lot drainage should not be disturbed. Surface drainage should be conducted from the rear yard to the street by a graded swale through the sideyard, or alternative approved devices. B) Roof and yard runoff should be conducted to either the street or storm drain by non-erosive devices such as sidewalks, drainage pipes, ground gutters, and driveways. Drainage systems should not be altered without expert consultation. Cl All drains should be kept clean and unclogged, including gutters and downspouts. Terrace drains or gunite ditches should be kept free of debris to allow proper drainage. During heavy rain periods, performance of the drainage system should be inspected. Problems, such as gullying and ponding, if present, should be corrected as soon as possible. D) Any bypassing of drains or leakage from pools, waterlines, etc., should be repaired as soon as possible. El Animal burrows should be filled as they may cause diversion of surface runoff, promote accelerated erosion, and even trigger shallow soil failures. - - j. H. KLEINFELDER & ASSOCIATES _- - - -. - - - - Ff G) Hf 1) J) Page 2 Slopes should not be altered without expert consultation. When a homeowner plans a significant topographic modification of a lot or slope, a qualified geotechnical consultant should be contracted. If plans for modification of cut, fill, or natural slopes within a property are considered, an engineering geologist should be consulted. Oversteepening may result in a need for expensive retaining devices. Undercutting of the bottom of a slope may lead to slope instability or failure and should not be undertaken without expert consultation. If unusual cracking, settling, or earth slippage occurs anywhere on the property, the homeowner should consult a qualified soil engineer or an engineering geologist immediately. The most common causes of slope erosion and shallow slope failures are: 0 Gross neglect of the care and maintenance of the slopes and drainage devices. 0 Inadequate and/or improper planting. (Barren areas should be replanted as soon as possible.) 0 Excessive or insufficient irrigation or diversion of runoff over the slope. 0 Foot traffic on slopes which destroys vegetation and exposes soil to erosion. Homeowners should not let conditions on their property create problems for their neighbors. Cooperation with neighbors may prevent problems, and also increase the aesthetic value of the properties. Winter Alert It is especial September. Do ly important to nwinterize*l your property by mid- not wait until spring to put in landscaping. YOU need winter protection. Final landscaping can be completed later. Inexpensive measures installed by mid-September provide immediate protection that will last through the vet season. 0 Check before storms to see that drains, gutters, downspouts, and ditches are not clogged by leaves and rubble. 0 Check after major storms to be sure drains are clear and vegetation is holding on slopes. Repair as necessary. J. H. KLEINFELDER & ASSOCIATES - Page 3 - - - - - - - - - - - Spot seed bare areas. Broadcast seeds or use a mechanical seeder. A typical slope or bare area can be seeded in less than an hour. Give seeds a boost with fertiliser. Mulch, if you can, with grass clippings and leaves, bark chips or straw. Use netting to hold soil and seeds on steep slopes. Check with your landscape architect or local nursery for advice. Prepare berms and ditches to drain surface runoff water away from problem areas such as steep, bare slopes. Prepare barren areas on slopes to hold seeds by raking the surface to loosen and roughen soil. Construction Plan construction activities during spring and summer, SC that erosion control measures can be in place when the rain comes. Examine your site carefully before building. Be aware of the slope, drainage patterns, and soil types. Proper site design will help you avoid expensive stabilization work. Preserve existing vegetation as much as possible. Vegetation will naturally curb erosion, improve the appearance and the value of your property, and reduce the cost of future landscaping. Use fencing to protect plants from fill material and traf fit. If it is necessary to pave near trees, do so with permeable asphalt or porous paving blocks. Disturb the earth as little as possible to preserve the natural contours of the land. Limit the time during which graded areas are exposed. Minimise the length and steepness of slopes by benching, terracing, or constructing diversion structures. Landscape benches areas to stabilise the slope and improve its appearance. Plant vegetation on all areas that are not being paved or otherwise covered as soon as possible after grading a site. .- I’I., ‘, - J. H. KLEINFELDER 81 ASSOCIATES - Page 4 Temporary Measures to Stabilize The Soil Grass provides the least expensive and most effective short-term erosion control. It grows quickly and covers the ground completely. To find the best seed mixtures and plans for your - area, check with your local landscape architect, local nursery or the U.S. Department of Agriculture Soil Conservation Service. - Mulches hold soil moisture and provide ground protection from --?--- rain damage. They also provide a favorable environment for starting and growing plants. Easy-to-obtain mulches are grass clippings, leaves, sawdust, bark chips, and straw. - - - - - - - - - - Straw mulch is nearly 100% effective when held in place by 1) spraying with an organic glue or wood fiber (tackifiers), 2) punching it into the soil with a shovel or roller, or 3) tacking a netting over it. Commercial applications of wood fibers combined with various seed and fertilizers (hydraulic mulching) are effective in stabilizing sloped areas. Hydraulic mulching with a tackifier should be done in two separate applications: the first composed of seed fertilizer and half the mulch, the second composed of the remaining mulch and tackifier. Commercial hydraulic mulch applicators - who also provide other erosion control services - are listed under *landscaping" in the phone book. Mats of excelsior, jute netting, and plastic sheets can be effective temporary covers, but they must be in contact with the soil and fastened securely to work effectively. Roof drainage may be collected in barrels or storage containers or routed into lawns, planter boxes, and gardens. Be sure to cover stored water SC it does not collect mosquitos. Excessive runoff should be directed away from your house. Excess water can damage trees and make foundations unstable. Structural Runoff Controls Even with proper timing and planting, you may need to protect disturbed areas from rainfall until the plants have had time to establish themselves, or you may need permanent way to transport water across your property so that it doesn't cause erosion. Some ways to reduce the volume and speed of soil removal by water from your site are: 0 Riprap (rock lining) - to protect channel banks from erosive water flow. l-m-l J. H. KLEINFELDER 81 ASSOCIATES - Page 5 - - - - - - - 0 Sediment trap - to stop runoff-carrying sediment and trap the sediment. 0 Storm drain outlet production - to reducethe speed of water flowing from a pipe onto open ground or into a natural channel. 0 Diversion dike or perimeter dike - todivertexcess water to places where it can be disposed of properly. 0 Straw bale dike - to stop and detain sediment from small unprotected areas (a short-term measure). 0 Perimeter swale - to divert runoff from a disturbed area or to contain runoff within a disturbed area. 0 Grade stabilization structure - to carry concentrated runoff down a slope. - -