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HomeMy WebLinkAbout; Laguna Riviera 29 Acres; Soils Report; 1981-05-04- - PRELIMINARY SOIL AND GEOLOGICAL INVESTIGATION FOR THE PROPOSED LAGUNA RIVIERA - 29 ACRES CARLSBAD, CALIFORNIA - Prepared For Kamar Construction Co., Inc. 325 Elm Avenue Carlsbad, California 92008 ENGINEERING DEPT. LIBRARY City of Carlsbad 2075 Las Pa!mas !irive carlsbaq CA 92GtKHE59 - - - ,.- - - - 3467 K”rtZ street San Diego. California 92110 714-224-2911 Telex 697-841 WoodwardGlyde Cons&ants May 4, 1981 Project No. SllOlW-SIOI Kamar Construction Co., Inc. 325 Elm Avenue Carlsbad, California 92008 Attention: Mr. Jerry Rombotis PRELIMINARY SOIL AND GEOLOGICAL INVESTIGATION FOR TBE PROPOSED LAGUNA RIVIERA - 29 ACRES CARLSBAD, CALIFORNIA Gentlemen: We are pleased to provide the accompanying report, which pre- sents the results of our geotechnical investigation for the subject project. The report presents our conclusions and rec- ommendations pertaining to the site, as well as the results of our field explorations. If you have any questions, or if we can be of further service, please give us a call. Very truly yours, WOODWARD-CLYDE CONSULTANTS Robert J. Dowlen C.E.G. 1011 RFJ/RPW/MP,R/JB/nun Attachments (5) Consulting Engineers. Geologists and Environmental Scientists Ofiices in Other Princioal Cities Richard P. While R.E. 21992 - - - - .- ,.- - - - -. Reference No. 51101W-SIOl WoodwardGyde Consultants TABLE OF CONTENTS PURPOSE OF INVESTIGATION BACKGRUND INFORMATION AND PROJECT DESCRIPTION Field and Laboratory Investigations SITE, SOIL, AND GEOLOGIC CONDITIONS Geologic Settinq Topography and Site Conditions Subsurface Conditions Page 1 2 3 4 : 4 Fill Soils (Qf) Topsoil (unmapped) Terrace Deposits (Qt) Santiago Formation (Tsa) Structure 6 Landslides 6 Ground Water 6 DISCUSSIONS, CONCLUSIONS, AND RECOMMENDATIONS 6 Potential Geologic Hazards 6 Faulting and Ground Breakage 6 Liquefaction 7 Landslides 7 Ground Water 7 General Soil Conditions 8 Slope Stability 8 Gradinq 10 Foundations 11 RISK AND OTHER CONSIDERATIONS FIGURE 1 - SITE PLAN APPENDIX A - FIELD INVESTIGATION 12 A-l - - - - ii Reference No. 511OlW-SIOl - - - - Woodward-Clyde Consultants TABLE OF CONTENTS (Continued) Page FIGURE A-l - KEY TO LOGS FIGURES A-2 THROUGH A-5 - LOGS OF TEST BORINGS FIGURES A-6 THROUGH A-8 - LOGS OF TEST PITS FIGURE A-9 - LOG OF CUT SLOPE APPENDIX B - LABORATORY TESTS B-l FIGURES B-l THROUGH B-2 - GRAIN SIZE DISTRIBUTION CURVES FIGURE B-3 - FILL SUITABILITY TESTS APPENDIX C - BORING 1 TAKEN FROM SOIL AND GEOLOGICAL INVESTIGATION FOR THE PROPOSED LAGUNA RIVIERA, UNIT 11, DATED FEBRUARY 23, 1981 APPENDIX D - SLOPE STABILITY D-l APPENDIX E - SPECIFICATIONS FOR CONTROLLED FILL E-l APPENDIX F - GUIDE SPECIFICATIONS FOR SUBSURFACE DRAINS F-l APPENDIX G - OVERSIZE ROCK PLACEMENT AREAS G-l - - - - - iii Reference No. 511OlW-SIOl Woodward-Clyde Consultants PRELIMINARY SOIL AND GEOLOGICAL INVESTIGATION FOR TBE PROPOSED LAGUNA RIVIERA - 29 ACRES CARLSBAD, CALIFORNIA This report presents the results of our preliminary soil and geological investigation at the site of the proposed Laguna Riviera - 29 Acres, residential subdivision. The site is located northwest of the intersection of Park Drive and Valencia Avenue, in the Ranch0 Agua Hedionda section of Carlsbad, California. Laguna Riviera Units 10 and 11 border the property to the east and northeast. PURPOSE OF INVESTIGATION The purpose of our investigation is to assist Kamar Construction Company, Inc., and their consultants in evalu- ating the property and in project design. This report pre- sents our conclusions and/or recommendations regarding: 0 Geologic setting of the site, 0 Potential geologic hazards, 0 General subsurface soil conditions, 0 General extent and condition of existing fill soils, 0 Condition of areas to receive fill, 0 Presence and effect of expansive soils, 0 Depth to water (if within the depth of our sub- surface investigation), 0 Types and depths of foundations and allowable soil bearing pressures. Reference No. SllOlW-SIOl Woodward-Clyde Consultants BACKGROUND INFORMATION AND PROJECT DESCRIPTION To aid in our study, we have discussed the project with Mr. Jerry Rombotis, and have been provided with an un- dated, "Tentative Map of Laguna Riviera, CT 80" (scale: 1" = 40'), prepared by Rick Engineering Company (Fig. 1). In addition, we have reviewed applicable geologic and geotech- nical data from adjacent areas, including: 0 "Soil and Geological Investigation for the Proposed Laguna Riviera, Unit 11, Carlsbad, California, pre- pared by our firm (February 23, 1981). 0 "Laguna Riviera Unit 10, CT-80 Carlsbad, California, Testing and Observation Services During Grading Operations; Final Report of Work from September 16 through October 10, 1980, prepared by Geocon, Inc.. (October 17, 1980) 0 "Soil Investigation for Laguna Riviera, Carlsbad, California," prepared by Geocon, Inc. (April 7, 1980). 0 "Laguna Riviera Unit 5, Offsite Fill Areas A and B, Carlsbad! California," prepared by Woodward- Gizienski &Associates (April 5, 1972). 0 "Faulting in the Oceanside, Carlsbad, and Vista Areas, Northern San Diego County, California," by :olwY of scamp Dennis Hannan, in Studies on the Ge Pendleton, and Western San Diego County, California, published by the San Diego Association of Geologist (1975). 0 "Geologic Map of a Portion of the San Luis Rey Quad- rangle, San Diego County, California,' M.S. thesis by Kenneth L. Wilson, University of California, Riverside (1972). We understand that the proposed project will involve grading the eastern approximate three-quarters of the 29-acre PUD parcel into level pads for construction of approximately 122 living units. We understand that the proposed construc- tion will be limited to one- and/or two-story, woodframe and - - 2 Reference No. 51101W-SIOl Woodward.Clyde Consultants - - ,- - stucco multi-family residential structures, supported on con- tinuous footings and having concrete slab-on-grade floors. We also understand that proposed cut and fill slopes will have inclinations of 2 to 1 (horizontal to vertical) or flatter, and will be a maximum of 30 feet high. Along the eastern property line, fill slopes of up to 30 feet high (3 to 1 inclination) and cut slopes with maximum heights of 15 feet (2 to 1 inclination) are proposed. These slopes will be an extension of existing cut and fill slopes which taper into Units 10 and 11. The existing slopes have 2 to 1 inclinations and are a maximum of 20 feet in height. Field and Laboratory Investigations Our field investigation included making a visual geologic reconnaissance of existing surface conditions, making four bucket auger boring and five backhoe test pits, and obtaining representative soil samples. The borings and test pits were advanced to depths of up to 34 feet and 10-l/2 feet, respectively. In addition, a log was prepared of an existing cut slope along Park Drive. The locations of these test explorations are shown on Fig. 1. A Key to Logs is presented in Appendix A as Fig. A-l. Simplified logs of the borings and test pits are presented in Appendix A as Figs. A-2 through A-8 . The cut slope log is shown on Fig. A-9. The descriptions on the logs are based on field logs and sample inspection. Results of the laboratory tests are shown at the corresponding sample loca- tions on the logs and in Appendix B. The field investigation and laboratory testing programs are discussed in Appendixes A and B, respectively. A copy of Boring 1 made during the investigation for the adjacent Unit 11, is shown. - - - - - Reference No. 511OlW-SIOl Woodward-Clyde Consultants SITE, SOIL, AND GEOLOGIC CONDITIONS Geologic Setting The site lies within an area characterised by Pleistocene age beach and lagoonal deposits overlying Tertiary age sediments of the coastal foothills. Topography and Site Conditions The site covers major portions of a broad south- trending ridge and the neigbboring southern flanks of a higher mesa surface. Elevations range from over 120 feet (MSLD) in the northern corner of the site to less than 14 feet along Park Drive in the central areas of the property (Fig. 1). Natural slope inclinations vary from a maximum of approximately 2 to 1 on the ridge flanks, to nearly flat on sections of the ridge top. Vegetation varies from a sparse growth of grasses in the southern regions to moderate to dense brush along the drainages and western sections. Compacted fill soils, placed in conjunction with the grading of Units 10 and 11, are present in drainages along the eastern site bound- ary. End-dumped fill and piles of loose topsoils and brush are also found in this general area. Existing cut and fill slopes, inclined at approximately l-1/2 to 1, are present along Park Drive and the eastern boundary. We understand that two water lines cross the north- ern most corner of the property with one line paralleling the northwest boundary line. Sewer and electrical utilities are present along Park Drive. - Subsurface Conditions The site is underlain by compacted fill soils, top- soil, Pleistocene age terrace deposits and the Eocene age Santiago Formation. These units are described below; their 4 Reference No. 511OlW-SIOl Woodward.Clyde Consultants - - - - - - area1 extents, with the exception of the topsoil, are approx- imately shown on Fig. 1. The geologic map symbol for each unit is given after the formal name for the unit. Fill Soils (Qf) - Undocumented fill soils, estimated to be up to approximately 8 feet in thickness, are present in drainage swales along the eastern boundary. These soils, visually classified as silty sands, appear to represent a regrading of existing natural drainage swales. Topsoil (unmapped) - A topsoil layer, composed of compressible silty sand grading to sandy clay, is present on the natural hillsides and beneath the loose fill soils in Test Pit 3. It is estimated that these soils range from 1 to 3 feetin thickness. Terrace Deposits (Qt) - The eastern two-thirds of the site is underlain by terrace deposits composed of dense silty to clayey sands containing randomly dispersed interbeds and lenses of sandy to silty clay. The sandy portions were found to range from lightly cemented to cohesionless and non- expansive to moderately expansive. The clay layers are gener- ally highly expansive. These materials were found to be in excess of 25 to 30 feetin thickness in the test borings. Santiago Formation (Tsa) - The entire site is under- lain by moderately well indurated, very fine to coarse silty to clayey sands of the Santiago Formation. Interbeds and clasts of sandy to silty clay are present within the sand with varying regularity and thickness. Cemented zones are locally present in this unit and may cause oversize materials to be generated during grading. We expect that the granular portion of the unit ranges from nonexpansive to moderately expansive; the claystone lenses are highly expansive. - .- Reference No. 511OlW-SIOl Woodward-Clyde Consultants - - Structure and Faultinq Our field investigation indicated that bedding within the Santiago Formation and terrace deposits is inclined in a southerly direction at approximately 10 degrees, and between 4 and 7 degrees, respectively. This orientation rep- resents a potentially adverse condition for all south-facing cut slopes. No faults or indications of faults were observed during our reconnaissance, and no faults are mapped on the site. - - - - - Landslides Our studies did not reveal the presence of land- slides on the site. Ground Water No ground water seeps, springs, or abnormally wet areas were observed during our visual reconnaissance or in the test excavations. - - DISCUSSIONS, CONCLUSIONS, AND RECOMMENDATIONS The discussions, conclusions, and recommendations presented in this report are based on the results of our field and laboratory studies, previous work in the area, analyses, and professional judgment. Potential Geologic Hazards - Faulting and Ground Breakage - Our reconnaissance, literature review, and subsurface explorations did not reveal the presence of any faulting on the site. The nearest known active fault along which seismic events of magnitude 4 or greater have occurred is in the Elsinore Fault zone, mapped some 22 miles to the northeast. 6 Reference No. 511OlW-SIOl Woodward-Clyde Consultants - The closest significant faulting is the northern extension of the Rose Canyon Fault zone, which is mapped off- shore approximately 9 miles to the southwest. No magnitude 4 or larger earthquakes have been recorded on the Rose Canyon Fault zone. Liquefaction - The formational soils on the site are dense to very dense, and there is no apparent permanent ground water table within expected grading limits. In our opinion, the formational soils do not have a potential for liquefaction. The topsoils have a potential for liquefaction in a saturated state. In our opinion, this potential can be essentially eliminated by over-excavation and recompaction as recommended under "Grading." Landslides - Our review and field investigations did not reveal the presence of any landslides on the site. .- - .~. .- - Ground Water Our field investigation did not reveal any ground water seeps, springs, or abnormally wet areas and we do not expect that a shallow permanent ground water table is present within the proposed grading limits. We recommend that positive measures be taken to properly finish grade each lot after the residential struc- tures and other improvements are in place, so that drainage waters from the lots and adjacent properties are directed off the lots and away from house foundations, floor slabs, and slopes. Even with these provisions, experience in adjacent areas has shown that a shallow ground water or surface water condition can and may develop in areas where no such water condition existed prior to site development; this is partic- ularly true in years of heavy rainfall and in residential sub- divisions where a substantial increase in surface water 7 - - - - - - - Reference No. SllOlW-SIOl Woodward-Clyde Consultants infiltration results from landscape irrigation. Examination of the subdivision during grading will help evaluate areas that could present future seepage problems in cut slopes. General Soil Conditions The materials expected to be used in structural fills and in constructed slopes are primarily silty to clayey sands containing sandy and silty clay interbeds. In our opinion, the soils on k-l e site can generally be excavated to design depths by light to moderate effort by heavy-duty excavation equipment. Excavation of localised cemented zones in the Santiago Formation may require heavier ripping, and may result in the generation of oversize material. Soils suitable for use at finish grade are present in the formations underlying the site; however, clayey strata have been identified in the excavations. The clay portions of the formational soils and surficial soils are highly expansive and unsuitable for use at finish grade. Selective grading may be required including stockpiling of finish grade soils in order to arrive at satisfactory finish grade conditions. Slope Stability We have performed stability analyses for the pro- posed slopes by the Janbu method using the following parameters: Parameter Undisturbed materials C’ - 300 psf 1 125 pcf Compacted Fill 25' 300 psf 125 pcf 8 Reference No. 511OlW-SIOl Woodward-Clyde Consultants - - - - - - ,- Our selection of soil parameters for analysis is based on the results of laboratory tests performed on samples during our field explorations and from studies on similar formational soils in the Carlsbad area. The results of those analyses indicate that the proposed 2 to 1 inclined fill and cut slopes, if free of claystone interbeds, have calculated factors of safety against deep-seated slope failure in excess of 1.5 for static condi- tions. Slope stability calculations are attached (Appen- dix D). South-facing slopes made in the terrace deposits may expose weak, southerly dipping, clay seams. It is our profes- sional judgment that cut slopes in excess of 10 feet in height with exposed weak clay seams have a moderate potential for slope instability if constructed as indicated. We recommend buttressing south-facing cut slopes with exposed weak clay seams that are in excess of 10 feet in height in accordance with the following sketch (see page 9A). This treatment may necessitate the slopes being overbuilt 3 feet and cutback to the finished grade surface. Stability analyses require using parameters selected from a range of possible values. There is a finite possibil- ity that slopes having calculated factors of safety, as indi- cated, could become unstable. .In our opinion, the probability of slopes becoming unstable is low, and it is our professional judgment that the proposed slopes can be constructed. We recommend that an engineering geologist from our firm inspect all cut slopes during grading to verify actual geologic conditions and to provide design modifications, if needed. It should be noted that friable, cohesionless sands were encountered in our test borings and may be exposed in the cut slope faces when grading is completed. These materials are extremely susceptible to erosion and may require special 9 _- - - -.. Note 1 Finish - Slope may be overbuilt and cut back -,/ Finish - Note 2 1 \Gravel Chimney Note 3 - SKETCH DETAIL AT MAXIMUM SECTION (NO SCALE) NOTES: (1) (2) (3) (4) Collector Collector Drain Drain CHIMNEY DRAIN DETAIL (NO SCALE) Safe construction slopes to be determined by the contractor. 6-inch diameter perforated thick walled PVC or ABS pipe. Outlet from buttress should be nonperforated and should slope to drain at convenient outlet. Outlet end shall be protected against damage and readily accessible for observation and maintenance. Class II permeable California State Specification Section 68-1.025 or combined aggregate State Specification, Section 90-3.04 l-inch maximum, 6-inch minimum encasement of drain pipe. Compacted granular soils. - - .- - 9a Reference No. SllOlW-SIOl Woodward-Clyde Consultants ,- - - landscaping procedures to reduce the potential for slope erosion due to irrigation and rainfall. Proper landscaping procedures should be recommended by the project landscape architect. Grading We recommend that all earthwork be done in accor- dance with the attached Specifications for Controlled Fill (Appendix E). Woodward-Clyde Consultants should observe the grading and test compacted fills. We recommend that a pre-construction conference be held at the site with the developer, civil engineer, contrac- tor, Andy geotechnical engineer in attendance. Special soil handling and the grading plans can be discussed at that time. We recommend that all trash, construction debris, brush piles, and waste materials be removed from the site before grading. We recommend that all porous topsoils and fill ~soils not removed by planned grading be excavated or scarified as required, watered, and then recompacted prior to placing any additional fill. We recommend that the soil engineer evaluate the actual depth and extent of excavation in the field at the time of grading. We recommend installing a subsurface drain beneath fills placed in the Neblina Drive easement in accordance with the attached Specifications for Subsurface Drains (Appen- dix F). We recommend that the subsurface drain be extended "upstream" in the drainage to the point where it is covered by a minimum 10 feet of fill. The actual location of the sub- drain will be evaluated and recommended when grading plans are available. We recommend that oversize materials (between 2 and 4 feet), if encountered, be placed in accordance with the attached Oversize Rock Placement Areas (Appendix G). We - 10 Reference No. 511OlW-SIOl Woodward-Clyde Consultants - - - - .- recommend that rock fragments larger than 4 feet be hauled from the site or broken into smaller pieces. Highly expansive clayey soils could be encountered at grade in areas of shallow cuts and fills (daylight areas), or in deeper cuts. We recommend that these clayey soils be excavated, where encountered, over the entire level lot area to a minimum of 2 feet below finish grade, and then be re- placed with properly compacted, nonexpansive soils or slightly expansive soils available on the site. The more clayey soils can be placed and properly compacted in the deeper fill areas. We recommend that the upper 2 feet of materials in the fill areas be composed of finish grade, granular soils. Finish grade soils are defined as granular soils that have a potential swell of less than 6 percent when recompacted to 90 percent of maximum laboratory density at optimum moisture content, placed under an axial load of 160 psf, and soaked in water. We recommend slightly to moderately expansive soils, that is soils swelling between 3 and 6 percent, be compacted at moisture contents of 3 to 5 percent over optimum water content when they are used within 2 feet of finish grade. Foundations We recommend that foundations for structures founded in natural or properly compacted, nonexpansive to moderately expansive soils be designed for an allowable soil bearing pressure of 2,000 psf (dead plus live load). In our opinion, this bearing pressure can be increased by up to one-third for transient loads caused by wind or seismic forces. For these bearing pressures, we recommend that all footings be founded a minimum of 12 inches below compacted fill or undisturbed cut lot grade, be a minimum of 12 inches wide, and be founded a minimum horizontal distance of 8 feet from slope faces. - 11 Reference No. 51101W-SIOl Woodward-Clyde Consultants - - - - - - - - - - - -- - We recommend that foundations founded in slightly to moderately expansive materials be reinforced top and bottom with at least one No. 4 steel bar, and that the concrete slabs-on-grade be a minimum 4 inches thick and be underlain by 4 inches of coarse, clean sand and reinforced by 6 x 6, lO/lO welded wire mesh. A plastic membrane should also be provided under slabs. RISK AND OTHER CONSIDERATIONS We have observed only a small portion of the perti- nent soil, and ground water conditions on the site. The recommendations made herein are based on the assumption that conditions do not deviate appreciably from those found during our field investigation. If the plans for site development change, or if variations or undesirable geotechnical condi- tions are encountered during construction, the geotechnical consultant should be consulted for further recommendations. We recommend that the geotechnical consultant review all grading and foundation plans before finalizing to verify that the intent of the recommendations presented herein have been properly interpreted and incorporated into the contract documents. We further recommend that the geotechnical con- sultant observe the site grading, and subgrade preparation under concrete slabs and paved areas, and foundation excavations. It should be understood that California is an area of high seismic risk. It is generally considered economically unfeasible to build totally earthquake-resistant structures; therefore, it is possible that a large or nearby earthquake could cause damage at the site. Professional judgments presented herein are based partly on our evaluations of the technical information - - 12 - - .- - - Reference No. 51101W-SIOl Woodward4lyde Consultants gathered, partly on our understanding of the proposed con- struction, and partly on our general experience in the geo- technical field. Our engineering work and judgments rendered meet current professional standards. We do not guarantee the performance of the project in any respect. This firm does not practice or consult in the field of safety engineering. We do not direct the contractor's operations, and we cannot be responsible for the safety of other than our own personnel on the site; therefore, the safety of others is the responsibility of the contractor. The contractor should notify the owner if he considers any of the recommended actions presented herein to be unsafe. - - - - - 13 - - - Project No. 511OlW-SIOl Woodward-Clyde Consultants APPENDIX A FIELD INVESTIGATION Four exploratory test borings and five test pits were made at the approximate locations shown on Fig. 1. Our field work was performed between February 2 and 5, 1981. The test borings were made with a truck-mounted 30-inch diameter bucket auger and were down-hole logged. The test pits were excavated by a John Deere Model 310-A backhoe. Representative samples of the subsurface materials were obtained from the test explorations and returned to our lab- oratory for examination. The locations of the test excavations and the ele- vation of the ground surface at each location were estimated from the plan prepared by Rick Engineering Company. - I - - - A-l Location - - - - ‘y: - 65 - DTWEI IEETE - Boring Number Elevation I R -LE NUllSEll SOIL DESCRIPTION I r- Very dense, damp, brown silty sand (SM) WATER LEVEL -I Af time Of drilling or as indicated. I L SOIL CLASSIFICATION I soil Clsrrificationr are bared on the ““i&d soi, Clarrifiotlo” s+rtsm aid i”d”ck mlor, mature an* conrirtency. Field de%lip,lo”l haYe he” modified to reflect re.u,u Of laboratcf” analyser Mere apprOpri.t*. DISTURBED SAMPLE LOCATION obtained b” collecting the auger C”,,i~S in a plmic or cloth b. DRIVE SAMPLE LOCATION MODlFlED CALlFORNlA SAMPLER SamPla With recorded tl,owr per ‘Dot was chained Wfh B Modi‘M California drive sampler lr’ ins!& diamem. 2.5” .Jurr,*e diamtrrl lined With sample t”t.s. The *m&r was driven ,“,.a ttm IOil at the bottom 0‘ the hole wtll a 140 &w”nd hammer falling 30 ,n*es. DRY DENSITY Pounds pr Cubic Foot MOISTURE CONTENT Rrcsnt Of my weight h INDICATES SAMPLE TESTED FOR OTHER PROPERTIES GS - Grain size Dinriburion CT - Conrolidatmn Tell LC - Laborator” G3moani.m “CS - “ncoon‘med comprerrion Test Test PI - Atferberg Limit* Test OS - Direct mea, Tel, ST - Loaded Swell Test TX - Triaxial Com,mrrion Test cc- Confined cnmprerrion Ten NOTE: In this column the rewlts of these tesis may be recorded where applicable. BLOW COUNT Number Of blowr readed to advance sampler one foot or II Indloted. NOTESON FIELD INVESTIGATION 1. REFUSAL indiotes th* inability 10 extend excavation, practically. With aq”iwnmt being “Iad in tlw inve,tig.*ion. - I KEY TO LOGS LAGUNA RIVIERA 29 ACRES I DRAWNW: ch O(ECKEDB": D,I ,ROJEclNO: SllOlW-SIOl DATE: 4-6-81 FlO”RENO: A-l WOODWARO-CLYDE CONSULTANTS - - .- - - - - - 15 7 1 I 20 20 - 25 25 i - (\- - - - --Grading to _ _ - - - I I- 22 - - - I Dense, damp, light gray brown, silty sand TERRACE DEPOSITS Grading to - - - - - - I Very stiff, moist, dark brown, silty clay (CH) TEFRACE DEPOSITS Dense, damp, gray brown, silty sand (SM) TERRACE DEPOSITS I’ Bottom of Hdle I I ‘For d.scription 01 symbol,. we Figw. ‘For d.scription 01 symbol,. we Figw. A-l A-l LOG OF TEST BORING 1 LOG OF TEST BORING 1 LAGUNA RIVIERA 29 ACRES LAGUNA RIVIERA 29 ACRES DRAWNBY: ch DRAWNBY: ch 1 CHECKE.DBY:~~j ,ROJECTNO: 51101W-SIOl 1 DATE: 4-6-81 1 CHECKE.DBY:~~j ,ROJECTNO: 51101W-SIOl 1 DATE: 4-6-81 FIGURE wo: A-2 FIGURE wo: A-2 IN - FEET l MC ’ OTHEF rEsls X,PI Boring 1 Approximate El. 49' 1 SOIL DESCRIPTION I \ Firm, moist, brown, silty clay (CH) TOPSOIL AND SLOPEWASH \ Loose, damp, brown, clayey sand (SC) TOPSOIL Dense, moist, brown, silty sand (SM) TERRACE DEPOSITS Bedding attitude N31E/4S very coarse sand with pebbles; firable Hard, damp, olive brown, silty to sandy \ clay (CH) TERRACE DEPOSITS -----_- Grading to - - - - - - Dense, damp, gray brown, clayey sand (SC) to sandy clay (CL) TERRACE DEPOSITS \-_ - -- - Grading to - - - - - Dense, damp, pale brown, silty sand (SM) TERRACE DEPOSITS - Bedding attitude N3lW/5S at 22%' Very stiff, moist, dark brown, silty clay (CH) TERRACE DEPOSITS L---- - Grading to - - - - - \ Dense, moist, gray,brown, clayey sand (SC) TERRACE DEPOSITS -. -. - - - - - - roj - 00 - - Boring 2 Approximate El. 79' >THER ‘ESTS T S S-AMPLE NUMBER I SOIL DESCRIPTION I Medium dense, moist, dark brown, silty sand \ (SM) i porous TOPSOIL Dense, damp, brown, clayey sand (SC) \ TOPSOIL -- - -- Grading to - - - -- Dense, moist, reddish brown, silty sand , (SM) TERRACE DEPOSITS L--e- Grading to - - - - - - Dense, moist, qray brown, clayey sand to sandy clay (SC-CL) TERRACE DEPOSITS . ---- Grading to- - _ _ _ Dense, moist, gray brown, silty sand (SM) TERRACE DEPOSITS - Bedding attitude N25W/4S at 13s' / Contact generally dipping to SW Very stiff, moist, qray green, silty clay \ (CH);some clay parting surfaces, many carbonate zones TERRACE DEPOSITS Dense, damp, light qray to dark brown, Silty to clayey sand (SM-SC) TERRACE DEPOSITS Hard, damp, gray brown, sandy to silty clay (CL) with shell fragments, many clay parting surfaces TERRACE DEPOSITS Dense, damp, light brown to gray, sandy silt (MH) some pockets of red brown sand TERRACE DEPOSITS Dense, damp, light qray brown, silty sand \ (SM) TERRACE DEPOSITS Bottom of Hole *For description of symbols, SW Figure A-l I I LOG OF TEST BORING 2 LAGLINA RIVIERA 29 ACP.ES DRAWNBY: ch 1 Cl,ECKEDBY:~$l PRWECTNO: 51101W-SIOl 1 DATE: 4-6-81 FIDURE ND! A-3 WnnrlWARn.EI VnF cnuwII TAYTS - 5 10 - 15 - 20 25 30 - r 01 - ‘DD - )THEI rEsTs S,PI lS,LC Boring 3 Approximate El. 94' I SOIL DESCRIPTION Loose, moist, dark brown, silty sand (SM); \ porous TOPSOIL \ Finn, damp, dark brown, sandy clay (CL) TOPSOIL Dense, moist, brown, clayey sand (SC) TERRACE DEPOSITS I- Lens of dark brown, silty clay (CH) -) Lens of grayish brown, silty clay (CH) Very stiff, moist, grayish brown, sandy \ clay (CL) TERRACE DEPOSITS Dense, moist, light qray brown, silty sand , (SM) TERRACE DEPOSITS \ Contact attitude approximately N75W/4S at 19' Stiff, moist, dark olive, silty clay (CH) TERRACE DEPOSITS Dense, damp, light gray brown, silty sand (34) TERRACE DEPOSITS Bottom of Hole ‘For d.scription of wymbal,. SW Fi(plr,A-1 I 1 LOG OF TEST BORING 3 LAGUNA RIVIERA 29 ACRES DRAWNBY: ch 1 C"ECKEDBY:@D] PROJECTNO: SllOlW-SIOl 1 DATE: 4-6-81 1 F‘OURE m):A-4 wnnIlwaD”.PI ““F rn”Clll TrlYTC - - - .- - -~ .- ; - DEPTH TES IN FEET l MC 25- 25- ITHE rEsTI S,P Boring 4 Approximate El. 119' BAMPLE YUMBER SOIL DESCRIPTION I Loose, damp, dark brown, silty sand (SM); porous TOPSOIL Dense, moist, red brown, silty sand (SM); trace clay TERRACE DEPOSITS ----- Grading to - -, - - - - Dense, -moi&, red brown to light olive brown, clayey sand (X'to sandy clay (CL) TERRACE DEPOSITS c Approximate bedding N70E/4S at 29' Very dense, damp, pale brown, clayey fine sand (SC);cemented SANTIAGO FORMATION Bottom of Hole *For d.wi,xion 01 wnbol,. se. Figure ~-1 LOG OF TEST BORING 4 LAGUNA RIVIERA 29 ACP.ES DRAWNBV: ch 1 CWECKEDW~1 PROJECTNO: 51101W-SIOl DATE: 4-6-81 1 FMWRE ~0: A-5 w”““wdnn.FI vns IYlYClll TaYTC Test Pit 5 Approximate El. 72' DEPTI c F:k ITHEF ‘EETE 5AMPLE WMEER SOIL DESCRIPTION Firm, moist, brown, sandy clay (CL) \ TOPSOIL Dense, damp, light brown, silty sand (SM) \ TEP.RACE DEPOSITS i‘ Hard, damp, dark olive, sandy clay (CL) TERFJACE DEPOSITS Contact attitude N20W/7S at 4#' Dense, damp, pale brown, silty sand (SM); friable TERRACE DEPOSITS \ Hard, moist, gray brown, silty to sandy clay (CH) TERRACE DEPOSITS i-l C i-2 C i-3 C i-4 C Bottom of Hole 15 - Test Pit 6 - Approximate El. 78' 4 T OTHEP TESTS I SAMPLE I NUMOER SOIL DESCRIPTION I Loose, moist, dark brown, silty sand (SM); \ PCZOUS TOPSOIL J 16-l L'"" GS,LC 6-2 6-3 :(6-4 L \ Hard,, damp, dark brown, sandy clay (CH) _--- - Grading to - - - - Very dense, damp, light gray, silty sand (SW SANTIAGO FORMATION Bottom of Hole - *For d.s.AFtim of .ymbolr. ,e. F&w. A-l LOG OF TEST PITS 5 AND 6 LAGUNA RIVIERA 29 ACRES DRAWNEY: ch 1 CHECKEDBY:~i, 1 PRDJECTN0: SllOlW-SIOl 1 DATE: 4-7-81 FlOUREIK):A-6 WOOOWARO-CLYDE CONSULTANTS - rm - DD - - - 8c - - . T - ITHEI ‘ESTS - S,PI - OTHE? TESTS DEPTH 1 FL l MC ‘i 5 10 I 15 1 iT DI - -00 - - Test Pit 7 Approximate El. 21' 1 SOIL DESCRIPTION Loose, moist, dark brown, clayey sand (SC) , TOPSOIL \ Dense, damp, dark brown, clayey sand (SC) TOPSOIL Dense, damp, pale brown, silty sand (SM) TERRACE DEPOSITS - Bedding attitude N8W/4S at 9' \ Dense, damp, dark brown, clayey sand (SC) i TERRACE DEPOSITS Bottom of Hole Test Pit 8 Approximate E1.35' ERMPLE NUMBER SOIL DESCRIPTION *For dmcrimion .a‘ wmbob. s.. ~imr. A-1 Loose, moist, dark gray brown, clayey sand (SC) TOPSOIL Dense, damp, dark gray brown, sandy clay (CL) TOPSOIL Hard, moist, brown, sandy clay (CL) RESIDUAL SOIL ----- Grading to - _ - _ - \ Very dense, damp, gray brown, clayey sand (SC) SANTIAGO FORMATION 'Contact attitude N40W/12S at 6' Very dense, damp, light gray, silty sand (34 SANTIAGO FORMATION Bottom of Hole LOG OF TEST PITS 7 AND 8 LAGUNA RIVIERA 29 ACRES DRAWNBY: ch 1 CHECKEDBY:RJD 1 PROJECTNO: 511OlW-SIOl 1 DATE: 4-7-81 FlGURE wo: A-7 .- - -. - 1 DEPTHi TI DTHEI rsrs i*L(PLE IVMBEF 3-1 a-2 C 3-3 [ 3-4 r Test Pit 9 Approximate El. 21' SOIL DESCRIPTION Loose, moist, light brown, silty sand (SM); \ TOPSOIL Dense, damp, dark brown, clayey coarse sand (SC) with shell fragments I TOPSOIL L- - -- Grading to - - - - - I Dense, moist, yellowish brown, clayey sand \ (SC) TERRACE DEPOSITS -_---_ Grading to ___ _ _ _ Dense, damp, dark brown, clayey sand to I sandy clay (SC-CL) TERRACE DEPOSITS ---- - Grading to _ _ Dense, damp, brown, clayey sand (SC) TERRACE DEPOSITS Bottom of Hole *Po,d.rription of ,ymbols,see Pigrn A-l LOG OF TEST PIT 9 LAGUNA RIVIERA 29 ACRES. DRAWIIIIY: ch 1 CHECKEDEX~9 [ ,N,.,ECTNO:5llOlW-SIOl 1 DATE: 4-7-81 1 FtOURE wo: A-8 WOOOWARO-CLYDE CONSULTANTS - - - -. - - - - - - - ,~~ 3THEI TESTS - cut slope 10 Approximate El. 62' , SOIL DESCRIPTION \ Firm, dry, pale brown, sandy clay to clayey sand (CL-SC) porous I TOPSOIL Firm, damp, light reddish brown, sandy clay Firm, damp, light reddish brown, sandy clay (CL) (CL) TOPSOIL TOPSOIL Hard, damp, light gray brown, fine sandy Hard, damp, light gray brown, fine sandy clay (CL) clay (CL) TERRACE DEPOSITS TERRACE DEPOSITS Hard, damp, olive to gray.to black, silty clay (CH) TERRACE DEPOSITS Dense, damp, pale brown, silty medium sand (SM) TERRACE DEPOSITS l"-3" lens of hard, damp, silty tray at 4+' 1"-2" l&s of hard, damp, balck to brown, sandy clay (CL) at 5'r' Hard, damp, olive brown, silty clay (CH) TERRACE DEPOSITS Contact attitude N38E/6S at 12' Dense, damp, gray brown, clayey very fine sand (SC) TERRACE DEPOSITS \ Dense, damp, light gray, silty sand (SM) TERRACE DEPOSITS \ Beddinq attitude N69E/6S at 18%' Hard, damp, olive gray, silty clay (CH) \ TERRACE DEPOSITS Contact attitude NlEW/7S at 214' Dense. damp, gray brown, clayey very fine sand (SC) TERRACE DEPOSITS Dense, damp, light gray, silty sand (SC) TERRACE DEPOSITS Bottom of Hole ~~ordercription of rymbdr,us ~igwe A-l 1 LOG OF CU1 C SLOPE 10 lAGUNA RIVIE RA 29 ACRES I DRAWNBY: ch 1 c"E‘ZKEDBY:~.\n 1 PRQlECTNO: SllOlW-SIOl DATE: 4-7-81 PIG”RE110: A-V WOOOWARD.CLYIlE CONSULTANTS Project No. 51101W-SIOl APPENDIX B LABORATORY TESTS Woodward-Clyde Consultants - - - - The materials observed in the test pits were visually classified and evaluated with respect to strength, swelling and compressibility characteristics; dry density; and moisture content. The classifications were substantiated by performing grain size analyses and evaluating plasticity characteristics of representative samples of the soils. Fill suitability tests, including compaction tests, expansibility tests, and grain size analyses, were performed on samples of the probable fill soils. The grain size distribution curves are shown on Fig. B-l. The results of fill suitability tests are reported on Figs. B-2 and B-3. - B-l - - COBBLES GRAVEL I SAND SILT and CLAY Coarse Fine Coarse Medi urn Fine Mesh Opening - Ins Sieve Sizes Hydrometer Analysis I 1 i I D 70 80 10.0 5.0 1.0 0. I 0.05 0.01 o.DD5 0.001 GRAIN SIZE IN HILLIHETERS *LL - Liquid Limit *PI - Plasticity Index I GRAIN SIZE DISTRIBUTION CURVES LAGUNA RIVIERA 29 ACRES I DRAWN~V: ch 1 CHECKED sv:E>, PROJECT NO: 51101W-SIOl DATE:4-7-81 FlOURa wo: B-1 WOODWARD-CLYDE CONSULTANTS - - - - I CoBGLES GRAVEL I SAND Cnarr* I SILT and CLAY ucrl i Fina I Mesh Opening - Ins Sieve Sizes Hydrometer Analysis r I , I loo 76 32 10 16203OW 0 90 IO 80 20 70 30 60 w:: f 2 50 “; z w 60: 30 70 20 60 IO so 0 100 loo 50 10.0 5.0 I.0 0.1 0.05 0.01 0.005 0.001 GRAIN SIZE IN HILLIHETERS *LL - Liquid Limit *PI - Plasticity Index GRAIN SIZE DISTRIBUTION CURVES LAGUNA RIVIERA 29 ACRES DRAWN BY: ch CHECKEDBY: w PROJECTNO: SllOlW-SIOl DATE: J-7-81 FIGURE No: B-2 WOOOWARO-CLYDE CONSULTANTS - PLASTICITY CHARACTERISTICS 3-2 6-4 - - 1E Liquid Limit, % Plasticity Index. % Classification by Unified Soil Classification Svstem - - SC SM I ~~~ -I--~~~~ ’ ’ $ I I ,w 5 Kl )LJ 40 5 ZERO AIR VOIDSCURVES P 20 0 loo0 loo 10 IO GRAIN SIZE. mm MECHANICAL ANALYSIS v DIRECT SHEAR TEST DATA 3-2 Dry Density, pcf 109 Initial Water Content. % 12 Final Water Content, % 20 Apparent Cohesion. psf 340 Apparent Friction Angle, degrees 16 SWELL TEST DATA LABORATORY COMPACTION TEST LABORATORY COMPACTION TESTMET,,OD:ASTM-D 1557-70 A .- FILL SUITABILITY TESTS LAGUNA RIVIERA 29 ACRFS DRAWN BY: ch 1 CnECKE~ q “: mu 1 PRwECT No: 51101w-s101 1 DATE: 4-7-81 PIOVRE NO+-’ Y,..m...Y.mm . . “IC -..“..a.. -*..-a - Project No. SllOlW-SIOl - - - WoodwardGlyde Consultants APPENDIX C Boring 1 Taken From SOIL AND GEOLOGICAL INVESTIGATION FOR THE PROPOSED LAGUNA RIVIERA, UNIT II Dated February 23, 1981 - - - - - - 25: - 30: _- --- 35- - - 40- - r 01 - ‘DD - - >THEI rESTS Boring 1 Approximate El. 53' AMPLE “MSER SOIL DESCRIPTION Loose, damp, red-brown, clayey to silty \ sand (SC-SM) TOPSOIL Dense, moist, brown, silty to silty clayey, medium sand (SM) with occasional red-brown staining TERRACE DEPOSITS Trace clayey gravels Contact attitude N4% 15'N Dense, moist, brown, silty coarse sand (SM-SP); lightly cemented and cohesionless TERRACE DEPOSITS - Cross-bedding N25'E 22OS at 14' - Clayey gravels Dense, moist, brown, clayey sand (SC) interbedded with stiff, moist, gray, sandy to silty clay (CL-CH) TERRACE DEPOSITS Dense, moist, gray-brown, silty medium sand (SW TERRACE DEPOSIIS 1 Becomes light gray-brown Bottom of Hole -For descriptio” 0‘ ,“mt.OlS. se pigun A-l LOG OF TEST BORING 1 LAG"NA RIVERIA UNIT 11 DRAWNBY: ch 1 CHECKED SVk&p PROJECT NO: 51101w- SIol DATE:~-12-81 PlGURE NO: A-2 , C-l WOODWARD-CLYDE CONSULTANTS - - - Project No. SllOlW-SIOl APPENDIX D SLOPE STABILITY Cut Slope - - - - -s - Assumptions: (1) Maximum height of slopes (2) Maximum slope inclination (3) Unit weight of soil (4) Apparent angle of internal friction (5) Apparent cohesion (6) No seepage forces B= 30 2 to 1 Y = 125 pcf $ = 330 c = 300 psf References: (1) Janbu, N., "Stability Analysis of Slopes with Dimensionless Parameters, II Harvard Soil Mechanics Series No. 46, 1954. (2) Janbu, N., "Dimensionless Parameters for Homogeneous Earth Slopes," JSMFD, NO. SM6, November 1967. Analyses: Safety Factor, F.S. = Ncf c Where 'Ncf is the stability YH number for slopes with both c and@. A cf = YH tan $ = 8.1 C From Fig. 10 of Reference (2) Ncf = 27 F.S. = 2.2 - -. - D-l - - - Project No. 511OlW-SIOl Slope Stability Fill Slope Assumptions: ,- (1) Maximum height of slopes (2) Maximum slope inclination (3) Unit weight of soil (4) Apparent angle of internal friction (5) Apparent cohesion (6) No seepage forces H = 30' 2 to 1 Y = 125 pcf $' = 25'= c = 300 psf - References: (1) (2) Janbu, N., "Stability Analysis of Slopes with Dimensionless Parameters," Harvard Soil Mechanics Series No. 46, 1954. Janbu, N., "Dimensionless Parameters for Homogeneous Earth Slopes," JSMFD, NO. SM6, November 1967. Analyses: Safety Factor, F.S. = Ncf C Where 'N cf is the stability YH number for slopes with both c and$. A cf = w tan 4 = 5.6 C From Fig. 10 of Reference (2) Ncf = 22 F.S. = 1.8 D-2 - . * APPENDIX E SPECIFICATIONS FOR CONTROLLED FILL I. GENERAL These specifications cover preparation of existing surfaces to receive fills, the type of soil suitable for use in fills, the control of compaction, and the methods of testing compac- ted fills. It shall be the contractor's responsibility to place, spread, water, and compact the fill in strict accord- ance with these specifications. A soil engineer shall be the owner's representative to inspect the construction of fills. Excavation and the placing of fill shall be under the direct inspection of the soil engineer, and he shall give written notice of conformance with the specifications upon completion of grading. Deviations from these specifications will be permitted only upon written authorization from the soil engineer. A soil investigation has been made for this pro- ject; any recommendations made in the report of the soil investigation or subsequent reports shall become an addendum to these specifications. II. SCOPE The placement of controlled fill by the contractor shall include all clearing and grubbing, removal of existing unsat- isfactory material, preparation of the areas to be filled, spreading and compaction of fill in the areas to be filled, and all other work necessary to complete the grading of the filled areas. III. MATERIALS 1. Materials for compacted fill shall consist of any mater- ial imported or excavated from the cut areas that, in the opinion of the soil engineer, is suitable for use in con- structing fills. The material shall contain no rocks or hard lumps greater than 24 inches in size and shall contain at least 40% of material smaller than l/4 inch in size. (Mater- ials greater than 6 inches in size shall be placed by the contractor so that they are surrounded by compacted fines; no nesting of rocks shall be permitted.) No material of a perishable, spongy, or otherwise improper nature shall be used in filling. 2. Material placed within 24 inches of rough grade shall be select material that contains no rocks or hard lumps greater than 6 inches in size and that swells less than 6% when compacted as hereinafter specified for compacted fill and soaked under an axial pressure of 160 psf. ,- ,- - E-l - 3. Representative samples of material to be used for fill shall be tested in the laboratory by the soil engineer in order to determine the maximum density, optimum moisture content, and classification of the soil. In addition, the soil engineer shall determine the approximate bearing value of a recompacted, saturated sample by direct shear tests or other tests applicable to the particular soil. 4. During grading operations, soil types other than those analyzed in the report of the soil investigation may be encountered by the contractor. The soil engineer shall be consulted to determine the suitability of these soils. IV. 1. (a) (b) 2. (a) (b) (c) COMPACTED FILLS General Unless otherwise specified, fill material shall be compacted by the contractor while at a moisture content near the optimum moisture content and to a density that is not less than 90% of the maximum dry density deter- mined in accordance with ASTM Test No. D1557-70, or other density test methods that will obtain equivalent results. Potentially expansive soils may be used in fills below a depth of 24 inches and shall be compacted at a moisture content greater than the optimum moisture content for the material. Clearing and Preparing Areas to be Filled All trees, brush, grass, and other objectionable mater- ial shall be collected, piled, and burned or otherwise disposed of by the contractor so as to leave the areas that have been cleared with a neat and finished appear- ance free from unsightly debris. All vegetable matter and objectionable material shall be removed by the contractor from the surface upon which the fill is to be placed, and any loose or porous soils shall be removed or compacted to the depth shown on the plans. The surface shall then be plowed or scarified to a minimum depth of 6 inches until the surface is free from uneven features that would tend to prevent uniform compaction by the equipment to be used. Where fills are constructed on hillsides or slopes, the slope of the original ground on which the fill is to be placed shall be stepped or keyed by the contractor as shown on the figure on Page 4 of these specifications. The steps shall extend completely through the soil mantle and into the underlying formational materials. E-2 .- . - - Id) 3. (a) 0) (cl (d) (e) V. 1. After the foundation for the fill has been cleared, plowed, or scarified, it shall be disced or bladed by the contractor until it is uniform and free from large clods, brought to the proper moisture content, and compacted as specified for fill. Placing, Spreadinq, and Compaction of Fill Material The fill material shall be placed by the contractor in layers that, when compacted, shall not exceed 6 inches. Each layer shall be spread evenly and shall be thorough- ly mixed during the spreading to obtain uniformity of material in each layer. When the moisture content of the fill material is below that specified by the soil engineer, water shall be added by the contractor until the moisture content is as specified. When the moisture content of the fill material is above that specified by the soil engineer, the fill matekial shall be aerated by the contractor by blading, mixing, or other satisfactory methods until the moisture content is as specified. After each layer has been placed, mixed, and spread evenly, it shall be thoroughly compacted by the contrac- tor to the specified density. Compaction shall be accomplished by sheepsfoot rollers, vibratory rollers, multiple-wheel pneumatic-tired rollers, or other types of acceptable compacting equipment. Equipment shall be of such design that it will be able to compact the fill to the specified density. Compaction shall be continu- ous over the entire area, and the equipment shall make sufficient trips to insure that the desired density has been obtained throughout the entire fill. The surface of fill slopes shall be compacted and there shall be no excess loose soil on the slopes. INSPECTION Observation and compaction tests shall be made by the soil engineer during the filling and compacting operations so that he can state his opinion that the fill was constructed in accordance with the specifications. 2. The soil engineer shall make field density tests in accordance with ASTM Test No. D1556-64. Density tests shall be made in the compacted materials below the surface where the surface is disturbed. When these tests indicate that the density of any layer of fill or portion thereof is below the specified density, the particular layer or portion shall be reworked until the specified density has been obtained. - E-3 - . . VI. PROTECTION OF WORK 1. During construction the contractor shall properly grade all excavated surfaces ,to provide positive drainage and prevent ponding of water. He shall control surface water to avoid damage to adjoining properties or to finished work on the site. The contractor shall take remedial measures to prevent erosion of freshly graded areas and until such time as permanent drainage and erosion control features have been installed. 2. After completion of grading and when the soil engineer has finished his observation of the work, no further excava- tion or filling shall be done except under the observation of the soil engineer. - - - - Remwe all topsoil -J Slope to be such that sloughing sliding does not occur ' Varies' '\ / ti- See note NOTES: The minimum width of "B" key shall be 2 feet wider than the compaction equipment, and not less than 10 feet. The outside edge of bottom key shall be below topsoil or loose surface material. Keys are required where the natural slope is steeper than 6 horizontal to 1 vertical, or where specified by the soil engineer. note - E-4 APPENDIX F GUIDE SPECIFICATIONS FOR SUBSURFACE DRAINS - - I. DESCRIPTION Subsurface drains consisting of filter gravel or gravel enclosed in filter fabric with perforated clean pipe shall with these be installed as shown on the plans in accordance specifications, unless otherwise specified by the engineer. II. MANUFACTURE Subsurface drain pipe shall be manufactured in accordance with the following requirements. Perforated corrugated ADS pipe shall conform to ASTM Designa- tion F405. Transite underdrain pipe shall conform to ASTM Designation C-508 (Type II). Perforated ABS and PVC pipe shall conform to ASTM Desginations 2751 and 3033, respect- ively, for SDR35; and to ASTM Designations 2661 and 1785, respectively, for SDR21. The type pipe shall conform to the following table. Pipe Material ADS Maximum Height of Fill (feet) (Corrugated Polyethylenej 8 Transite 'underdrain' PVC or ABS: SDR35 SDR21 III. FILTER MATERIAL 20 35 100 Filter material for use in backfilling trenches around and over drains shall consist of clean, coarse sand and gravel or crushed stone conforming to the following grading require- ments. Sieve Size 1 I@ 3/4" 3,'8" 4 8 30 50 200 Pcrcfntagc Passing Sieve 100 90 - 100 40 - 100 25 - 40 . 18 - 33 5- 15 o- 7 o- 3 This material generally conforms with Class II permeable material in accordance with Section GE-l.025 of the Standard Specifications Of the State of California, Department of Transportation. F-l - IV. FILTER FABRIC Filter fabric for use in drains shall consist of Mirafi 140 (Cclancse), Typar (,DuPont), or equivalent. The aggregate shall be 3/4-inch to l-l/Z-inch maximum size, free draining agqrcgate. Filter fabric shall completely surround the aggregate. V. LAYING Trenches for drains shall be excavated to a minimum width of 2 feet and to a depth shown on the plans, or as directed by the engineer. The bottom of the trench shall then be covered full width by 4 inches of filter material or with filter fabric and 4 inches of aggregate, and the drain pipe shall be laid with the perforations at the bottom and sections shall be joined with couplers. The pipe shall be laid on a minimum slope of 0.2 percent and drained to curb outlet or storm drain. After the pipe has been placed, the trench shall be back- filled with filter material of 1-l/2-inch maximum size aggregate if filter fabric is used to the elevation shown on the plans, or as directed by the engineer. - - - - - . ‘ F-2 .~ _ - - - - - TYPICAL SUBSUP.FACE DRAIHS FOR LOCAL SEEPAGE Compacted Compacted Filter I.\aterial or Filter Fabric 6" Perforated Pipe Drain to Curb Outlet or Storm Orair, ,-Compacted Native Soil cut Slope -7 Filter Fabric 6" hrforated Pipe -.I Drain to Curb Outlet or Storm Drain Line SeepaGe Lize Compacted --‘-Filter Ihtcrial or Filter Fabric - 6” l'crfor~ Lctl Pipe Llr~iin to Curl) Outlet or s Lo!w 01~~1 i I, - - - F-3 - - - TYPICAL SECTION SUBSURFACE DRAINS IN DffiWS - " CC:.:PACTP;D FILL FILL ~:ic,-,'i.~,T: '3:1 ~:ic,-,‘i.~,T: ‘3:1 24" :.,I,,. CC:.:PACTP;D DRAIN fIrI:: 6 INC!I ORIGINAL CROWD ORIGINAL CROWD $,gyi’: ,:., c:;: _ f\i.I.:;‘s’i;.si. I:.i:,.s:i’.!i’I’ 12 ” :,! I I, . ,: - ,.A FILTER I4AT!:I!T,,L: 7 vf/ft or I.i:!:cri,, -~ I.1 I :I . - - - ;’ I /,I,: - - ICI’ :.!I:/. 1 ::A:,: I:!llZ-i Iil:ICI1'1' I'!,' !‘i:.L :.!;%‘I’: :!J , I’\, ;,i!;.‘,i: !!“,‘,“,‘I’:., c:!. ‘\:.I.,:y!;\,. ,‘I,,:,,:ii”ll’l rr7’. 1 ,;:;L (C’:!~i.fIf;,‘tTI:j> / I,l.‘:.l,:?!i‘il.i.::!:) :: Tl’;s:;Gll’i: !!:!!,!:pl>,?;\r:: .1: I [“.‘C oc :‘,I!>‘: !;Lk 35 1 -I JOI< :11 : ‘!‘l F-4 - TYPICAL SECTION SUBSURFACE DRAINS IN DRAWS - 0RIG::IAL GROUflD FILTER FABRIC ALL AROOUND - np;,;:: i’[;.!t; 6 I!!C!I DIAM1:TER PIPE !~i,,v:T<T IiT. rm:i r:~luf~l ,I~:IG,I’r or‘ I~‘1 1.1. Al?OVK Hr)'rTOl~l or ,ll.I.IJ\'I;\T. CLi:.mnlu- (3. ) ;,!,:; (~:';!:i.l;r;;,'I'!:r) Po,."i:TIIYi.,:l;!:, il 'l'!';~::;; ITi. I1iID~:il~)kA~~~ :!I) I”?(: or nir.s : :IDI< ?5 1 5 .A , j I’ 2 1 1or1 - - - - APPENDIX G *. OVERSIZE ROCK PLACEMENT AREAS (No Scale) - - - - - - - - Ye; ffjgg Hi”lxurn 51o^,e I COVCT I _. LEGEND 0 ." Place no oversize rocks in this area. q Oversize rock can be placed in this area. ,” NOTES (1) Oversize rocks are those rock fragments between 2 feet and 4 feet in maximum dimension. (2) Rocks between 2 feet and 4 feet in size should be pro- perly isolated and completely surrounded by properly compacted soil. (3) No rocks greater than 4 feet in maximum dimension can be used in fills. (4) The oversize rock should be surrounded by sufficient fines to obtain proper compaction. (5) No oversize rock can be placed within 4 feet of finish lot grade or within expected depth of utilities, which- ever is deeper. - - G-l