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Home My WebLink About; Stagecoach Park; Stagecoach Park Geotechnical Investigation; 1985-07-01GEOTECHNICAL INVESTIGATION FOR STAGECOACH PARK CARLSBAD, CALIFORNIA For ' CITY OF CARLSBAD Carlsbad, California By GEOCON, INCORPORATED San Diegc, California July, 1985 GEOCON INCORPORATED ENGINEERS AND GEOLOGISTS • CONSULTANTS IN THE APPLIED EARTH SCIENCES File No. D-3480-J01 July 5, 1985 City of Carlsbad 1200 Elm Avenue Carlsbad, California 92008 Attention: Subject: Gentlemen: Mr. Dave Bradstreet STAGECOACH PARK CARLSBAD, CALIFORNIA GEOTECHNICAL INVESTIGATION In accordance with the request of Mr. Steven Lang of RSI Architecture and our proposal dated May 21, 1985, we have performed a geotechnical investigation of the subject property. The accompanying report presents our findings as well as conclusions and recommendations relating to the geotechnical aspects of developing the property as proposed. If you have questions or if we may be of further service, please contact the undersigned. Very truly yours, GEOCON, INCORPORATED fames E. Likins ICE 17030 MRR:JEL:lm mdrew E. Farkas ' CEG 1185 (3) addressee (3) RSI Architecture (1) Rick Engineering, Carlsbad Michael R. Rahilly RCE 28188 9530 DOWDY DRIVE • SAN DIEGO, CALIFORNIA 92126 • PHONE (619) 695-2880 TABLE OF CONTENTS GEOTECHNICAL INVESTIGATION Page Purpose and Scope 1 Site and Project Description 1 Soil and Geologic Conditions 3 Santiago Peak Volcanics 3 Delmar Formation 3 Marine Terrace Deposits 4 Ancient Landslides 4 Alluvial Soils 4 Topsoil 5 Groundwater 5 Faulting and Seismicity 6 CONCLUSIONS AND RECOMMENDATIONS General 7 Potential Geologic Hazards 7 Groundwater Conditions 8 Soil and Excavation Characteristics 8 Slope Stability 9 Grading 10 Foundations 11 Concrete Slabs-on-Grade 12 Site Drainage and Moisture Protection 13 Grading Plan Review 13 LIMITATIONS AND UNIFORMITY OF CONDITIONS 14 Figure 1, Site Plan (pocket) Figure 2, Slope Design Chart Figure 3, Typical Buttress Detail Figure 4, Recommended Canyon Subdrain Detail APPENDIX A FIELD INVESTIGATION Figures A-l - A-3, Logs of Test Borings Figures A-4 - A-ll, Logs of Test Trenches APPENDIX B LABORATORY TESTING Table IA, Moisture-Density and Direct Shear Test Results Table IB, Compaction Test Results Table 1C, Expansion Index Test Results APPENDIX C RECOMMENDED GRADING SPECIFICATIONS GEOCON INCORPORATED File No. D-3480-J01 July 5, 1985 GEOTECHNICAL INVESTIGATION Purpose and Scope The purpose of this study was to evaluate the soil and geologic conditions which would affect the development of the Stagecoach Park development as proposed by the present tentative map. Conclusions and recommendations pertaining to the geotechnical aspects of grading, slope stability and foundation design were to be included in the report. Tthe investigation included a site reconnaissance and the excavation of three test borings and 11 test trenches. Logs of the test excavations as well as other details of the field investigation are presented in Appendix A. Laboratory tests were performed on selected representative samples obtained at various depths in the test borings to evaluate pertinent physical characteristics of the soils types encountered. A summary of laboratory tests performed is included with the test results in Appendix B. Site and Project Description The approximately 28 acre site is located west of and adjacent to Mission Estancia easterly of its intersection with Rancho Santa Fe Road in the City of Carlsbad, California (see Site Plan and Geologic Map, Figure 1). Topographically, the property consists of gently northerly-sloping hillside terrain with elevations ranging from a high of approximately 245 feet along -1- GEOCON INCORPORATED File No. D-3480-J01 July 5, 1985 the southern property line to a low of approximately 160 feet in the bottom of the stream drainage adjacent to Mission Estancia in the western portion of the site. Natural drainage is accomplished through a relatively broad drainage area roughly paralleling the northern property line. Vegetation consists of dense stands of wild grasses and brush over the majority of the site. Large trees are present in the broad drainage area near Mission Estancia. Several dirt roads are present near the southern property boundary and some adobe ruins surrounded by a chain-link fence are present on the ridge in the central portion of the site. At the time of the investigation, Mission Estancia was under construction. According to the "Master Plan, Stagecoach Park, City of Carlsbad" prepared by RSI Incorporated (undated), it is proposed to develop the property to receive a recreational park. The park will include three baseball diamonds, four tennis courts, a gymnasium-community building and associated car parking, restroom concession buildings and hiking trails. Grading plans are not available, however, the Master Plan and the available Topographic Map indicates that cut and fill slopes will have maximum heights on the order of 35 feet at maximum inclinations of 2.0 to 1.0 (horizontal to vertical). It is anticipated that maximum cut and fill depths will be on the order of 30 feet. If project details vary significantly from those outlined, Geocon, Incorporated should be notified for review and possible revision of the recommendations presented herein prior to final design subinittal. GEOCON INCORPORATED File No. D-3480-J01 July 5, 1985 Soil and Geologic Conditions The site is underlain by the Jurassic-age Santiago Peak Volcanics, the Tertiary-aged Delmar Formation, Pleistocene-aged Marine Terrace Deposits and three surficial deposits consisting of landslide debris, alluvium and topsoils. The soil units are described below in order of increasing age. Santiago Peak Volcanics. Jurassic-age materials of the Santiago Peak Volcanics were encountered in the extreme northeastern part of the property northerly of the main drainage area. These materials consist primarily of weakly metamorphosed volcanic and sedimentary rocks in various stages of decomposition. Due to their limited extent, it is our opinion that the Santiago Peak Volcanics will be of little or no consideration for the future development. Delmar Formation. The Tertiary-aged Delmar Formation consisting of medium stiff to hard, moist, tan to light brown sandstones and reddish- brown, olive gray, sandy claystones were found to underlie the majority of the site. This formation is known for its inherently weak claystone beds and typically requires slope stabilization measures for cut slopes exposing the clay—rich portions. As indicated on Figure 1, a suspected ancient landslide has been mapped within this unit near the base of the ridge in the western portion of the property, and a zone of soil creep was noted in the eastern area of the site= Xn addition to ^ossessin^ relatively l*~*w shear strength, the more clayey portions of this formation are highly -3- GEOCON INCORPORATED File No. D-3480-J01 July 5, 1985 expansive and typically require selective grading or specially designed foundations. Excavation within this formation should encounter little difficulty with conventional grading equipment. Marine Terrace Deposits. Relatively recent Stream Terrace Deposits unconformably overlie the Tertiary-aged sediments and are exposed near the base of the slope in the central portion of the property. The Terrace Deposits consist of dense to very dense, reddish-brown, silty to clayey sands and sandy clays with numerous angular metavolcanic rock fragments. The Terrace Deposits had an observed thickness on the order of 2 to in excess of 6 feet. Ancient Landslides. Topographic features as well as observed exposures of disturbed formational soils suggest the presence of an ancient landslide near the base of the slope in the western portion of the property. The estimated limits of the suspected landslide is depicted on the Geologic Map, Figure 1. It is our preliminary opinion that the suspected slide masses will require buttressing for effective stabilization. Hummocky features generally indicative of shallow soil creep were observed in the eastern portion of the site in the area of the proposed baseball fields. Due to the unstable nature of these soils, deeper than normal keying and benching procedures would be likely where fill placement is planned. Alluvial Soils. The alluvial soils are typically composed of loose to medium dense, porous, silty to sandy clays and clayey sands that have -4- GEOCON INCORPORATED File No. D-3480-J01 July 5, 1985 accumulated near the base of slopes or along canyon bottoms. The maximum observed thickness in the areas to be developed was found to be on the order of 5 feet. It is anticipated that the alluvial soils in the main drainage area would have thicknesses in excess of 15 to 20 feet. It is our understanding that this main drainage area is not proposed for development. Development within areas containing alluvial or colluvial deposits will require remedial grading in the form of removal and recompaction to mitigate potential settlement problems. Topsoil. The majority of the site was found to be covered by stiff to very stiff, gray, sandy clay topsoils. In general, the topsoils possess moderate to high expansion potential and average 1 to 2 feet in thickness. Due to the loose, unconsolidated condition of the topsoils as well as their expansive potential, remedial grading measures, such as recompaction, deeper than normal sideslope fill keys and undercutting of transition pads, will be necessary. Groundwater Groundwater was not encountered in any of the test excavations at the time of the field investigation. It is anticipated that groundwater is present in the main drainage channel in the northern portion of the property. A small pond is present in the main drainage area near Mission Estancia. -5- GEOCON INCORPORATED File No. D-3480-JOL July 5, 1985 Faulting and Seismicity It is our opinion, based on the site reconnaissance and a review of published geologic maps and reports, that the site is not located on any known fault trace. The nearest known active fault is the Elsinore Fault zone which lies approximately 26 miles to the northeast. -6- GEOCON INCORPORATED File No. D-3480-J01 July 5, 1985 CONCLUSIONS AND RECOMMENDATIONS General 1. No soil or geologic conditions were encountered which, in our opinion, would preclude the development of the site as tentatively planned, provided the recommendations of this report are carefully followed. 2. The presence of ancient landslides, weak claystones and compressible alluvial soils and topsoils will require remedial grading and slope buttressing. Potential Geologic Hazards 3. No faults or indications of faults were mapped on the site during our field reconnaissance or field investigation. The closest known active faults to the site are the Elsinore and San Jacinto Faults located approxi- mately 26 miles and 50 miles northeasterly of the site, respectively. The offshore projection of the potentially active Rose Canyon Fault zone is located approximately 6 miles west of the site. The site area could be subjected to moderate to severe ground shaking in the event of a major seismic occurrence along any of the active faults in the Southern California area, however, in our opinion, the seismic risk for the project is not significantly different than that of the nearby areas. 4. The field investigation indicates that areas of ancient landsliding and soil creep are present within the Delmar Formation materials along the -7- GEOCON INCORPORATED File No. D-3480-J01 July 5, 1985 project sideslopes. The estimated limits of the the landslides and soil creep are depicted on the Site Plan and Geologic Map, Figure 1. In general, the slide masses can be stabilized by buttressing during grading. The hummocky features indicative of shallow soil creep were observed in the eastern portion of the property. Remedial grading and slope buttressing may be required as recommended under "Slope Stability" below. Groundwater Conditions 5. No groundwater, water seeps or marshy areas were noted in the areas to be developed during the current site investigation. It is not anticipated that a permanent groundwater table is present within proposed grading depths. It is anticipated that a groundwater table is present within the main drainage area. A small pond was noted in the western portion of the property near Mission Estancia. Soil and Excavation Characteristics 6. The soil units on-site can be grouped into three classes, soils that are moderately to highly expansive (topsoils, alluvial soils, and clay portions of the Terrace and Delmar Formations), soils that are compressible (portions of the alluvial and topsoils, and the upper portions of the landslide and soil creep areas), and soil suitable for use at finish grade (sandy portions of the Terrace materials and Delmar Formation). 7. It is our opinion that the materials can be excavated with moderate effort with conventional heavy-duty grading equipment. Excavation of the -8- GEOCON INCORPORATED File No. D-3480-J01 July 5, 1985 alluvial soils may encounter some wet conditions requiring drying of the wet soils to facilitate compaction. Slope Stability 8. Slope stability analyses have been performed using shear strength parameters based on laboratory testing and experience with similar materials from nearby areas. The analyses indicates that cut slopes within the granular materials and properly compacted fill slopes inclined at 2.0 to 1.0 or flatter will have calculated factors of safety in excess of 1.5 for heights of at least 40 feet (see Slope Design Chart, Figure 2). 9. The investigation indicates that weak claystones may be exposed in cut slopes on the site. Where these claystones are exposed in proposed cut slopes, slope buttressing or stability fills are recommended. The Site Plan and Geologic Map, Figure 1, indicates the approximate locations where slope buttressing is anticipated. The investigation also indicates that buttresses constructed within the existing landslide in the central-western portion of the site will be required. The approximate limits of the slope buttressing are shown on Figure 1 and a typical cross-section of a slope buttress is shown on Figure 3. Other smaller slopes may also require buttressing or stability fills depending on conditions exposed. Stability fills would typically consist of a recompacted slope having a recompacted width equal to the height of the slope or at least one equipment width, whichever is greater. More detailed buttress recommendations can be presented when grading plans are developed. -9- GEOCON INCORPORATED File No. D-3480-J01 July 5, 1985 10. It is recommended that all cut slopes and buttress excavations be inspected during grading by an engineering geologist to evaluate that the soil and geologic conditions do not differ significantly from those anticipated. Grading 11. All grading should be performed in accordance with the "Recommended Grading Specifications" contained in Appendix C. Where the recommendations of this section conflict with Appendix C, the recommendations of this section take precedence. All earthwork should be performed with testing and observation serviced provided by Geocon, Incorporated. 12. It is recommended that a pre-construction conference be held at the site with the owner, contractor, civil engineer and soil engineer in attendance. Special soil handling and/or the grading plans can be discussed at that time. 13. All loose, compressible topsoils, alluvial soils and areas of soil creep not removed by planned grading operations should be excavated to firm natural ground and the excavated material then moisturized or dried as necessary and properly compacted. 14. To reduce the potential for future groundwater or seepage problems, it is recommended that subsurface drains be installed in the canyons to be filled. The recommended location of the subsurface drains are shown on -10- GEOCON INCORPORATED File No. D-3480-J01 July 5, 1985 Figure 1. A typical detail of the drain system is presented as Figure 4. The actual location and depth of the subsurface drains should be evaluated by the geotechnical engineer during grading. The subsurface drains should be as-built for location and elevation by the project civil engineer. 15. The upper 3 feet of soil in cut or fill areas where buildings are proposed should be composed of "very low" to "low" expansive soil available on-site. "Very low" to "low" expansive soil is defined as soil having an expansion index of 50 or less when tested in accordance with UBC Standard 29-2. 16. To reduce the potential for differential settlement, it is recommended that structures not be placed on cut-fill transition lines. The cut portion of any such building pad should be undercut at least 3 feet below the proposed finish grade, the excavated material watered as required, replaced and properly compacted. Highly expansive material should be replaced as recommended above. Foundations 17. The following recommendations assume that low expansive soils (Expansion Index of 50 or less) will exist at finish grade. If this is not feasible, further recommendations will be provided by this office following grading operations on a building-by-building basis. 18. The site is suitable for use of isolated spread footings or continuous strip footings if graded as recommended above. Such footings should be at -11- GEOCON INCORPORATED File No. D-3480-J01 July 5, 1985 least 12 inches in width and should extend at least 18 inches below lowest adjacent pad grade. Footings located near the top of a slope should be deepened such that the bottom outside edge of the footing is at least 7 feet horizontally from the face of the slope. Footings for the restroon and concession buildings may be designed with widths and depths of at least 12 inches below lowest adjacent pad grade. 19. It is recommended that minimum continuous strip footing reinforcement consist of two No. 4 reinforcing bars placed horizontally in the footings, one near the top and one near the bottom. 20. The recommended reinforcement recommended above is based on soil characteristics only and is not intended to be in lieu of reinforcement necessary for structural considerations. 21. An allowable bearing capacity of 2,000 psf may be used for foundations constructed as recommended above. The allowable bearing capacity is for dead plus live loads and may be increased by one-third for transient loads such as wind or seismic forces. Concrete Slabs-on-Grade 22. Concrete slabs should have a thickness of 4 inches and should be ; underlain by at least 4 inches of clean sand or crushed rock. Reinforcement should consist of at least 6x6-10/10 welded wire mesh placed at the slab midpoint throughout. Where moisture sensitive floor coverings are planned, -12- GEOCON INCORPORATED File No. D-3480-J01 July 5, 1985 an impervious membrane barrier should be utilized covered by a 2-inch layer of the sand cushion to reduce shrinkage cracking and assist proper curing of the concrete. Site Drainage and Moisture Protection 23. Providing and maintaining adequate site drainage and moisture protection of supporting soils is an important design consideration. Foundation recommendations presented herein assume proper site drainage will be established and maintained. Under no circumstances should water be allowed to pond adjacent to footings. The site should be graded such that surface drainage flow is directed away from foundations and into swales or other controlled drainage facilities. Grading Plan Review 24. It is recommended that the grading plans be reviewed by this office prior to finalizing. The need for additional comments and/or analysis can be determined at that time. All proposed buttress and subdrain locations and design details should be shown on the final grading plans. -13- GEOCON INCORPORATED File No. D-3480-J01 July 5, 1985 LIMITATIONS AND UNIFORMITY OF CONDITIONS 1. The recommendations of this report pertain only to the site investigated and are based upon the assumption that the soil conditions do not deviate from those disclosed in the investigation. If any variations or undesirable conditions are encountered during construction, or if the proposed construction will differ from that planned at the present time, Geocon, Incorporated should be notified so that supplemental recom- mendations can be given. 2. This report is issued with the understanding that it is the responsibility of the owner, or of his representative, to ensure that the information and recommendations contained herein are brought to the attention of the architect and engineer for the project and incorporated into the plans, and the necessary steps are taken to see that the contractor and subcontractors carry out such recommendations in the field. 3. The findings of this report are valid as of the present date. However, changes in the conditions of a property can occur with the passage of time, whether they be due to natural processes or the works of man on this or adjacent properties. In addition, changes in applicable or appropriate standards may occur, whether they result from legislation or the broadening of knowledge. Accordingly, the findings of this report may be invalidated wholly or partially by changes outside our control. Therefore, this report is subject to review and should not be relied upon after a period of three years. ~w~ GEOCON INCORPORATED SLOPE 'DESIGN Tl H' 00 C Statistical analysis of 255 trial circles reveals that use of a factor of safety of 1.89 and Taylor's charts is not significantly different from the use of a factor of safety of 1.5 and a seismic load of 0.1G .The chart below,is based on factors of safety of 1.5 and 1.89 and Taylor's chart. Enter the chart from the bottom left with the given slope ratio. Go up to the appropriate"ffi"curve (dashed for seismic)proceed right to the"c"curve. Read allowable heights top(with seismic) and bottom(without seismic). CH SlopeHeight with Seismic. ^O "o *Q *fi *a *«. » ;Q •Slope Ratio V Slope height without Seismic £_, rrj C H- 00 IUl U)-(^00.oI .P. 3.24.70 File No. D-3480-J01 July 5, 1985 EXISTING GROUND __SHEAR_ZONE (BEDDING PLANE FAUUT NOTE 4 * NOTE 5 BUTTRESS v/ FILL ( NOTE NOTE 6 I NOTE Z FINISHED LOT GRADE UNDISTURBED FORMATIONAL SOIL NO SCALE NOTES 1. Excavate backslope at 1.0 to 1.0 inclination beginning 15 feet (minimum) from top of slope. 2. Base of buttress to be 5 feet below pad grade. 3. Buttress fill to be composed of properly compacted granular soil. 4. Chimney drains to be 12-inch by 24-inch slots spaced approximately 30 feet center-to-center and filled with filter material. Chimney drain should extend at least 5 feet above the shear zone. 5. Filter material to be either Class II permeable material in accordance with State of California Standard Specifications Section 68-1.025 or 1-inch open-graded crushed rock enclosed in filter fabric. 6. Collector pipe to be 4-inch minimum diameter, perforated, thick- walled PVC or BS sloped to drain and connected to storm drain or canyon subdrain. TYPICAL BUTTRESS DETAIL STAGECOACH PARK CARLSBAD, CALIFORNIA Figure 3 GEOCON INCORPORATED File No. D-3480-J01 July 5, 1985 APPROVED FILTER FABRIC 6" -. 4' 00 o Q 1 / Qs> 0o BEDROCK ( FORMATIONAL SO\L ) 0 ° 0 00 O <7 OPEN-GRADED I MAX. AGGREGATE 6 PERFORATED SCHEDULE 80 ABS PIPE, l" TO 2" CLEAR FROM BOTTOM OF TRENCH N 0 T E : IF CLASS 2 PERMEABLE MATERIAL ( PER SEC. 68-1.025 CALTRANS STANDARD SPECIFICATIONS ) IS USED THE FILTER FABRIC MAY BE DELETED RECOMMENDED CANYON SUBDRAIN DETAIL STAGECOACH PARK CARLSBAD, CALIFORNIA Figure 4 GEOCON INCORPORATED soils APPENDIX A GEOCON INCORPORATED File No. D-3480-J01 July 5, 1985 soils APPENDIX A FIELD INVESTIGATION The field investigation was performed during the period of June 13 through June 20, 1985 and consisted of excavating three test borings and 11 test trenches. The test borings were advanced with a Mobile B-50 truck-mounted drill rig utilizing. 6-inch-diameter continuous flight auger. Relatively undisturbed drive samples were obtained by driving a 3-inch O.D. sampler equipped with brass rings with blows from a 140-pound hammer falling 30 inches. The test trenches were advanced with a 24-inch-wide backhoe mounted on a John Deere 510 tractor. Disturbed bulk samples were obtained in both the test borings and test trenches. The results of the excavations are presented on the logs of test excavations in Appendix A. GEOCON INCORPORATED File No. D-3480-J01 July 5, 1985 X ,_ 0 2- - - 4- - 8- - 10- • 1 9 - 1 A - - 16- - 18- " " - 20- - - 22-SAMPLE NO. 1Jog o X Ij // / 1-1 H pi 1-2 X V1-3 m 1-4 •• / '\ I/ :1: '.': /1 i /' / / / ( // \ / '•M , // w ^ <\ / / Y / ''GROUNDWATERJSOIL CLASS 1(U.S.C.S.) 1BORING 1 Fl FVATION DATE DRILLED 6/13/85 FO.MPMFMT Mobile B-50 MATERIAL DESCRIPTION TOPSOIL Very stiff, dry to damp, dark gray, Silty CLAY A \ l- Dense, damp, orange-brown, Silty SAND DELMAR FORMATION Very stiff, damp, light green-brown, Silty CLAY to Clayey SILT Very stiff, damp, light red-brown, Sandy CLAY Very stiff to hard, light green-brown, Silty CLAY to Clayey SILT BORING TERMINATED AT 20.5 FEET PENETRATIONRESISTANCEBLOWS/ FT.• 50 • 50/ ' 6" 50/r 4V DRY DENSITYP.C.F.110.0 BULK 112.3 120.2 MOISTURECONTENT, %23.8 SAMPLE 17.3 12.8 Figure A-l, Log of Test Boring 1 SAMPLE SYMBOLS U SAMPLING UNSUCCESSFUL H —. DISTURBED OR BAG SAMPLE IJ STANDARD PENETRATION TEST ml _ CHUNK SAMPLE DRIVE SAMPLE (UNDISTURBED) WATER TA8LE OR SEEPAGE NOTE:! AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACECONDITIONS AT OTHER LOCATIONS AND TIMES GEOCON INCORPORATED File No. D-3480-J01 July 5, 1985 £ K "* ™ - 2 - - - 4 - • — < )£ _ - 8 - - - 10 - - 12 - - 14 - - -16 - - - 18 ' -20 ' - • 22 -SAMPLE NO.2-1 2-2 2-3 2-4 LITHOLOGYx\ \ 1 I/ /A £ 1 // y X m /™ '' H*-.V: •M w?l 'O'S ''$}'• •"o. '• ' Q •^•vV- '/' '6. * • ' '•: ^ !/&• >fe0 4:.:* a:5ROUNDWATEW 1CO BORING 2 Fl FVATION DATE DRILLED 6/13/85 FOIIIPMFNT Mobile B-50 MATERIAL DESCRIPTION TOPSOIL Stiff, dry to damp, dark gray-brown, Silty CLAY ~ very moist DELMAR FORMATION Very stiff, moist to wet, light green-brown, Silty CLAY to Clayey SILT Very stiff to hard, damp, dark gray-green, Sandy to Silty CLAY with occasional gypsum chunks and small pebbles BORING TERMINATED AT 20.5 FEET z,,,PENETRATIORESISTANCEBLOWS/ FT.- • 39 50/ • 6" 50/ ' 6" >i—coZU-LU <j ><r Q L04.8 L10.9 3ULK 5• LOS. 3 MOISTURECONTENT, %20.5 16.2 AMPLE 20.2 Figure A-2, Log of Test Boring 2 SAMPLE SYMBOLS LJ SAMPLING UNSUCCESSFUL S DISTURBED OR BAG SAMPLE U-_ STANDARD PENETRATION TEST *J— CHUNK SAMPLE 0 _^ DRIVE SAMPLE (UNDISTURBED! ?• _ WATER TABLE OR SEEPAGE NOTE: ATTHE DATE INDICATED. ITISNOTWARRANTEDTO BE REPRESENTATIVEOFSUBSUHFACECONOITIONS AT OTHER LOCATIONS AND TIMES GEOCON INCORPORATED File No. D-3480-J01 July 5, 1985 H . 0 . ~ . 2 . ^ m 4 )6: . 8 . - - 10 - — . - 12 - - 16 - - - 18- - 20- - 22- - 9/i « X: _ o oZo — - 30- 32 SAMPLE NO.3-1 3-2 3 3 3-4 3-5 LITHOLOGY/ '/ I/I /\\ Y\ VX I' ;il: V/l ' -j ' '/\j • ' 1 . • .. A , • / ' ' • • • •'':./: 93 • .X' TV- :'J-.': > ''•$• =*' ' "^- •.;jy^> ^ 1 I/ 1 ^ 1r * 1 lx x} Xf i • i '/•' j/i-j/i ^5ROUNDWATER |=»•SOIL CLASS(U.S.C.S.)BORING 3 Fl FVATIDN DATE DRILLED 6/13/85 MATERIAL DESCRIPTION TOP SOIL Very stiff to hard, dry to damp, dark gray- ~\ brown, Silty CLAY DELMAR FORMATION Very stiff, moist, light gray-green, Silty CLAY Very dense, damp, light tan, Silty SAND grades to light green, Clayey SAND Very dense, damp, light tan, Silty SAND with trace clay Break in log Very stiff, moist, yellow-brown, Silty CLAY to Clayey SILT Very stiff, damp to moist, gray, Silty CLAY to Clayey SILT Very stiff, damp, dark red to red-brown, Silty CLAY Very stiff, damp, gray-brown to gray, Silty CLAY to Clayey SILT "\ BORING TERMINATED AT 30.5 FEET 'PENETRATIONRESISTANCEBLOWS/FT." • . " 5l°n . ' B 507• 412" • 507 . 6" 507 t— COZLL tU(J o: Q 110.6 BULK I 110.6 MOISTURECONTENT, %9.9 AMPLE 9.0 Figure A-3, Log of Test Boring 3 SAMPLE SYMBOLS LJ SAMPLING UNSUCCESSFUL K — DISTURBED OR SAG SAMPLE U_ STANDARD PENETRATION TEST B — CHUNK SAMPLE DRIVE SAMPLE (UNDISTURBED) WATER TABLE OR SEEPAGE NOTE:'GEOCON INCORPORATED File No. D-3480-J01 July 5, 1985 z \- 2j-S Q "" - 2 - » « A - 8 - -10 - - 0 - - 2 - - 4 - . - 6 - - 8 - \ . -10 - -12 - •dz LU_J CL 2 CO >OO O 1- — 1 'f':\-\£ '.'.'. :'.' •"•'. • . ; * 'i * ' '•' :'••'•' ; .:• i; ;••;; :;];.;|;; n •x^- ..'X /^::: :-X^: ••:-'// / CE LUh-•?5 LJ2 Ou. CO yD -"•*<co' °^oSto TRENCH 1 FI FVATION DATE DRILLED 6/20/85 FOIIIPMFNT JD 51° MATERIAL DESCRIPTION TOPSOIL \ Stiff, dry, blackish-gray, Sandy CLAY DELMAR FORMATION Very dense, humid to moist, tan to light brown, well graded SANDSTONE Hard, moist, olive, very fine, Silty SANDSTONE/SILTSTONE TRENCH TERMINATED AT 9.0 FEET TRENCH 2 TOPSOIL Soft, humid, blackish-gray, Sandy CLAY DELMAR FORMATION Medium stiff, moist, highly fractured, mottled reddish-brown to gray, Sandy CLAYSTONE /—-grades into very stiff to hard, massive, J gray, Gritty CLAYSTONE TRENCH TERMINATED AT 11.0 FEET o'Vr~ -^ 1 1 <<co KCO| zLUm Q_Lt - . • • • > zu: LLJ(J QCL £T Q LU# Qw k " I3Z «H 2° ^ Figure A-4, Log of Test Trenches 1 and 2 SAMPLE SYMBOLS LJ SAMPLING UNSUCCESSFUL K — DISTURBED OR BAG SAMPLE U STANDARD PENETRATION TEST m CHUNK SAMPLE DRIVE SAMPLE (UNDISTURBED) WATER TABLE OR SEEPAGE NOTE: 1 ATTHE DATE INDICATED. ITIS NOT WARRANTED TOBE REPRESENTATIVEOFSUBSURFACECONOITIONS ATOTHER LOCATIONS AND TIMES GEOCON INCORPORATED File No July 5, D-3480-J01 1985 x K uj-ftQ u" - 0 - - 9 . - - 4 - 6 -0 - - 8 - - - 10 - - 12 - - - 14 - - l fi - dz LU Q_ co >OO o :•/'•. • . • •/:.''•/.• • -_/f\ • '•'/•''•'•' •'•'•'/ •'. ! i/v'- / • ' ': / : : X; '• '-"/^ • • /••:•. '••' •/• '•'fi'- /----/:;•.•?:•:; •':'•.'.'••' ^^ /?*^ <^^ f •/•'••:'•. '';••'•/;'•'! •/>•'•''•'Q'A. enLU 1Q Z ocr COco —<co °^o=ico ^. ^"'~ — ^^.^— ._ TRENCH 3 Fl FVATION DATE DRILLED 6/20/85 FOUIPMFNT JD 51° MATERIAL DESCRIPTION TOPSOIL Soft, moist, grayish-brown, Sandy CLAY A COLLUVIUM Soft to medium stiff, moist, reddish-brown, Sandy CLAY with numerous angular metavolcanic rock fragments LANDSLIDE DEBRIS Medium stiff, moist, mottled rust red-olive, fractured, sheared CLAY i — hard, highly cemented SANDSTONE fragments / -i minor shear zone grades into loose, soft, moist, highly disturbed, intermixed reddish-olive CLAY /SAND \ TRENCH TERMINATED AT 15.0 FEET oV ^ ~Z. ^" "^ ^ CO i— c/5 ^* —^ C/3 ] Q_ - • . • • • • • > co ZU- LU (J QCL cr Q LU# = 2 «H ^8 Figure A-5, Log of Test Trench 3 SAMPLE SYMBOLS U — SAMPLING UNSUCCESSFUL C3 — DISTURBED OR SAG SAMPLE STANDARD PENETRATION TEST m CHUNK SAMPLE DRIVE SAMPLE (UNDISTURBED) WATER TABLE OR SEEPAGE NOTE: THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLYATTHE SPECIFIC BORING OR TRENCH LOCATION AND ATTHE DATE INDICATED. ITISNOTWARRANTED TO BE REPRESENTATIVEOFSUBSURFACE CONDITIONS ATOTHER LOCATIONS AND TIMES GEOCON INCORPORATED File No. D-3480-J01 July 5, 1985 f Hj ~ ™ - 2 - - 4 - - 8 - - - 10 - - - 12 - - 14- - 16-SAMPLE NO.LITHOLOGY I//'-": ' : ' ^ $•••:• W( ;.;;)>;'. /- '•'•'.' '.''.' '•.'•'/• •"•;/*:• •/::.:\ •v^: *''.•'•:: "•••'••:• \\^%GROUNDWATERJC/3 <3j P TRENCH 4 ELFVATION DATE DRILLED 6/20/85 FOIIIPMFNT JD 51° MATERIAL DESCRIPTION TOPSOIL Soft, moist, blackish-gray, Sandy CLAY LANDSLIDE DEBRIS Loose, moist, highly disturbed, mottled olive gray-reddish-brown, Clayey SAND with numerous small SILTSTONE/CLAYSTONE f ragements becomes wet numerous black zones with organics TRENCH TERMINATED AT 15.0 FEET PENETRATIONRESISTANCEBLOWS/FT.• • m • - ' • * •DRY DENSITYP.C.F.MOISTURECONTENT, %Figure A-6, Log of Test Trench 4 SAMPLE SYMBOLS D SAMPLING UNSUCCESSFUL C3 DISTURBED OR BAG SAMPLE U_ STANDARD PENETRATION TEST •J CHUNK SAMPLE DRIVE SAMPLE (UNDISTURBED) WATER TABLE OR SEEPAGE NOTE: THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY ATTHE SPECIFIC BORING OR TRENCH LOCATION AND AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS ATOTHER LOCATIONS AND TIMES GEOCON INCORPORATED File No. D-3480-J01 July 5, 1985 x h Q . 0 ~ "• - 2 - - 4 - - \ 6 - - 8 - - - 10 - - 12 - _ 0 . 2 . . 4 . - . 6 . ^ ' r 8 • - 10 -SAMPLE NO.'LITHOLOGY'tf-::.' •'.:•'•/. •ffii / / / ./ // B///////3ROUNDWATER |SOIL CLASS(U.S.C.S.)TRENCH 5 Fl FVATION DATE DRILLED 6/20/85 FOIIIPMFNT JD 51° MATERIAL' DESCRIPTION TOPSOIL Soft to medium stiff, dry to humid, blackish- gray, Sandy CLAY DELMAR FORMATION Highly weathered fractured, moist, mottled purplish-gray CLAYSTONE grades into fractured, gray, moist, gritty CLAYSTONE TRENCH TERMINATED AT 11.0 FEET TRENCH 6 TOPSOIL Soft, humid to dry, blackish-gray, Sandy CLAY DELMAR FORMATION Highly fractured, weathered, calichefied, humid, olive CLAYSTONE i — grades into very stiff, moist, slightly / fractured, dark olive CLAYSTONE with shiny J parting surfaces 1 TRENCH TERMINATED AT 9.0 FEET PENETRATIONRESISTANCEBLOWS/FT.• - - • . • - * • . . •DRY DENSITYP.C.F.MOISTURECONTENT, %Figure A-7 , Log of Test Trenches 5 and 6 SAMPLE SYMBOLS — SAMPLING UNSUCCESSFUL K — DISTURBED OR BAG SAMPLE B — STANDARD PENETRATION TEST B — DRIVE SAMPLE (UNDISTURBED) B — CHUNK SAMPLE ?• __ WATER TABLE OR SEEPAGE NOTE: THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY ATTHE SPECIFIC BORING OR TRENCH LOCATION AND ATTHE DATE INDICATED. ITISNOTWARRANTEDTO BE REPRESENTATIVEOFSUBSURFACECONDITIONSATOTHER LOCATIONS AND TIMES GEOCON INCORPORATED File No. D-3480-J01 July 5, 1985 I f— gjSul Q ^ - 2 - - 4 - 1 6-J - 8 - - - 10 * " ™ - 12 • - 14 - - 16 - . 0 . . 2 . v-y . 6 . -_ 8 _ - Oz UJ Q. ^> OT >- CDO_iO />.;/ '/ • ^•j^°// ° Ocy/ y' t> OB- / /O /0 // °/ / 0 / / / / / '•/•'.••:•*. .•'•/'. • ' : .'••//•_ /' '•'••'. :•"••/' '•':/. . '.'.-. ccUJi—<£Q Z utrCD £/)CO . — • <(/) "^ w TRENCH 7 Fl FVATION DATE DRILLED 6/20/85 FOIIIPMFMT JD 51° MATERIAL DESCRIPTION TOPSOIL ~\ Soft, dry, blackish-gray Sandy CiAY \ 1 TERRACE DEPOSITS 1 Medium stiff, moist, reddish-brown, Sandy 1 CLAY with numerous angular, metavolcanic \ rock fragments 1 DELMAR FORMATION Highly fractured, weathered, moist, mottled purplish-olive gritty CLAYSTCNE, occasional pebble-size quartz fragements within the CLAYSTONE i grades into very stiff, slightly fractured, / moist to wet, mottled dark reddish-brown J to gray CLAYSTONE TRENCH TERMINATED AT 15.0 FEET TRENCH 8 TOPSOIL \ Very loose, dry, blackish-gray, Clayey SAND TERRACE DEPOSITS Very dense, moist, reddish-brown, Clayey SAND with numerous angular metavolcanic rock fragments — : — becomes hard, slow trenching "\ TRENCH TERMINATED AT 8.0 FEET OQI-^• " — » Ll •£<c/5 LLf — OT fjj I rr. LLI £QQ_ • • • — " 1—C/} ZLLUJ(Jj >crQ UJ#rr^ i ~ ^Z «H {^J *. 20 Figure A-8, Log of Test Trenches 7 and 8 SAMPLE SYMBOLS LJ SAMPLING UNSUCCESSFUL ^ — DISTURBED OR BAG SAMPLE U STANDARD PENETRATION TEST ki_ CHUNK SAMPLE DRIVE SAMPLE (UNDISTURBED) WATER TABLE OR SEEPAGE NOTE: THE LOG OF SUBSURFACE CONDITIONS SHOWN HE REON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION ANDAT THE DATE INDICATED IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS ATOTHER LOCATIONS AND TIMES GEOCON INCORPORATED File No. D-3480-J01 Julv 5, 1985 x ,_ - - 2 - - 4 - r] - 8 - "• - 10 - . - 12 - - - 14 - — 1 A - ?;SAMPLE NO. 1LITHOLOGY' •f" '"'• • ' '"'•/ 'tfy- / / / ' / / ' / / / / /3ROUNDWATER |co CO — Ico v^ > S TRENCH 9 ELEVATION DATE DRILLED 6/20/85 EQUIPMENT JD 510 MATERIAL DESCRIPTION TOPSOIL Soft, humid, black Sandy CLAY BEDROCK CREEP Soft to medium stiff, moist, highly fractured, weathered, calichefied, light gray CLAYSTONE with numerous randomly oriented minor shear planes • Shear Zone, soft, moist, remolded, light / gray CLAY with numerous CLAYSTONE fragements / and randomly oriented minor shear zones J DELMAR FORMATION Fractured, moist, light gray CLAYSTONE with numerous randomly oriented minor shear planes \ TRENCH TERMINATED AT 15.0 FEET i PENETRATIONRESISTANCEBLOWS/FT.• • • m DRY DENSITYP.C.F.MOISTURECONTENT, %Figure A-9, Log of Test Trench 9 SAMPLE SYMBOLS U SAMPLING UNSUCCESSFUL K — DISTURBED OR BAG SAMPLE U — STANDARD PENETRATION TEST B CHUNK SAMPLE DRIVE SAMPLE (UNDISTURBED) WATER TABLE OR SEEPAGE NOTE. THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS ATOTHER LOCATIONS AND TIMES GEOCON INCORPORATED File No. D-3480-J01 July 5, 1985 |-i - 2 - - 4 - - 8 - - 10 - -17- - - 14 - - 16 - 6 SAMPLEO LITHOLO'•/•'•••'• '•'•••/• '/•:• •:•. '•.^'•'•. // //' / / CCLU *3ROUND\AC/D 1 \ TRENCH 10 ELEVATION DATE DRILLED 6/20/85 FOIIIPMFNT JD 51° MATERIAL DESCRIPTION ALLUVIUM Very loose, moist, dark gray, Clayey SAND BEDROCK CREEP Soft to medium stiff, moist, highly fractured, weathered, mottled, purplish- brown to gray CLAYSTONE _ Shear Zone, soft, moist, highly sheared, / light gray CLAY j DELMAR FORMATION Fractured, very stiff, moist to wet, light gray CLAYSTONE TRENCH TERMINATED AT 15.0 FEET Zoj .O(JH-Pz^-<<coCCI— >(-</)§£«2 5^ • • . t • m • • • > w ZU-LU (jQQ:>crQ ^QUJ CT-KK $QZ^o^0 Figure A-10, Log of Test Trench 10 SAMPLE SYMBOLS LJ SAMPLING UNSUCCESSFUL (3 — DISTURBED OR BAG SAMPLE U-_STANDARD PENETRATION TEST •J_ CHUNK SAMPLE DRIVE SAMPLE (UNDISTURBED) WATER TABLE OR SEEPAGE NOTE: THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY ATTHE SPECIFIC BORING OR TRENCH LOCATION AND ATTHE DATE INDICATED. ITIS NOT WARRANTED TO BE REPRESENTATIVE OFSUBSURFACECONDITIONS AT OTHER LOCATIONS AND TIMES GEOCON INCORPORATED File No. D-3480-J01 July 5, 1985 £-£Q . 0 J - 2 _ . 4 . * — . 8 . - 10 -12 - -14 - ) ; dz UJ CL CO •oO O X ^•'.':." '•'•'•" f-$y. |f •:"•'•.'•>?; "'.-•'.' * ( // / cr LU\ —5 ^QZ g CO C/3^^ j . "^ CO x > TRENCH 11 ELEVATION DATE DRILLED 6/20/85 JD 510EQUIPMENT MATERIAL DESCRIPTION TOPSOIL Soft, moist, black Sandy CLAY TERRACE DEPOSITS Medium stiff, moist, light brown, Sandy CLAY grades into dense, moist, light brown, weakly cemented SANDSTONE with numerous caliche and gypsum crystals highly calichefied zone Very dense, light brown, moist, weakly \ u cemented SANDSTONE with occasional quartzite and metavolcanic rock fragments 1 UhLrlAK rUKrlAlIUN \ Stiff to very stiff, moist, mottled, purple- \ olive-gray, fractured CLAYSTONE with shiny \ parting surfaces TRENCH TERMINATED AT 14.0 FEET 2LU f-z^- <£ <3" f/5 l-</>5 Q. • • . • > COzu: LU(J QCL trQ LU ^ CCK-- COf— ^ 7 Figure A-ll, Log of Test Trench 11 SAMPLE SYMBOLS LJ SAMPLING UNSUCCESSFUL C3 — DISTURBED OR BAG SAMPLE _STANDARD PENETRATION TEST kJ__ CHUNK SAMPLE DRIVE SAMPLE (UNDISTURBED) WATER TABLE OR SEEPAGE NOTE: AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES GEOCON INCORPORATED soils APPENDIX B GEOCON INCORPORATED File No. D-3480-J01 July 5, 1985 soils APPENDIX B LABORATORY TESTING Laboratory tests were performed in accordance with generally accepted test methods of the American Society for Testing and Materials (ASTM) or other suggested procedures. Selected relatively undisturbed samples were tested for their in-place dry density, moisture content, drained shear strength, consolidation characteristics, and expansion potential. The maximum dry density and optimum moisture content of selected bulk samples were determined in accordance with ASTM Test Procedure D1557-70, Method A. Portions of the bulk samples were then remolded to selected densities and subjected to drained direct shear tests and Expansion Index tests. The results of the laboratory tests are presented in tabular form herein. The in-place dry density and moisture content are also presented on the boring logs. GEOCON INCORPORATED File No. D-3480-J01 July 5, 1985 TABLE IA Summary of In-Place Moisture-Density and Direct Shear Test Results Sample No. 1-1 *l-2 1-3 1-4 2-1 2-2 2-4 3-1 *3-2 3-3 Dry Density pcf 100.0 101.7 112.3 120.2 104.8 110.9 105.3 110.6 109.4 110.6 Moisture Unit Content Cohesion % psf 23.8 450 14.9 290 17.3 12.8 20.5 16.2 20.2 9.9 12.8 300 9.0 440 Angle of Shear Resistance Degrees 28 5 25 47 *Sample remolded to approximately 90 percent of maximum dry density at near optimum moisture content. GEOCON INCORPORATED File No. D-3480-J01 July 5, 1985 TABLE IB Summary of Laboratory Compaction Test Results ASTM D1557-70 Sample No. 1-2 3-2 Maximum Dry Density Description pcf Gray-green, Gray-green, Sandy CLAY 113.2 Clayey SAND 121.8 Optimum Moisture % Dry Wt. 14.5 12.2 TABLE 1C Summary of Laboratory Expansion Index Test Results Sample No. 1-2 3-2 3-3 Moisture Content Before After Test Test 15.5 37.3 10.8 21.9 1.9 15.8 Dry Density pcf 92.2 106.8 109.1 Expansion Index 109 42 0.1% air dry swell GEOCON INCORPORATEP soils APPENDIX C GEOCON INCORPORATED File No. D-3480-J01 July 5, 1985 RECOMMENDED GRADING SPECIFICATIONS 1. General 1.1 These specifications have been prepared for grading of Stagecoach Park located in Carlsbad, California. They shall be used in conjunc- tion with the soil report for the project dated July 1, 1985 prepared by Geocon, Incorporated. 1.2 The contractor shall be responsible for placing, spreading, watering, and compacting the fill in strict confonnance with these specifica- tions. All excavation and fill placement should be done under the observation of Geocon, Incorporated. Geocon, Incorporated should be consulted if the contractor or owner wishes to deviate from these specifications. 1.3 The grading should consist of clearing, grubbing, and removing from the site all material the Soil Engineer designates as "unsuitable"; preparing areas to be filled; properly placing and compacting fill materials; and all other work necessary to conform with the lines, grades, and slopes shown on the approved plans. 2. Preparation of Areas to be Graded 2.1 All trees and shrubs not to be used for landscaping, structures, weeds, and rubbish should be removed from the site prior to commencing any excavating or filling operations. 2.2 All buried structures (such as tanks, leach lines, and pipes) not designated to remain on the site should be removed, and the resulting depressions should be properly backfilled and compacted prior to any grading or filling operations. 2.3 All water wells should be treated in accordance with the requirements of the San Diego County Health Department. The owner shall verify the requirements. 2.4 All vegetation and soil designated as "unsuitable" by the Soil Engineer should be removed under his observation. The exposed surface should then be plowed or scarified to a depth of at least 12 inches until the surface is free from ruts, hummocks, or other uneven features that would prevent uniform compaction by the equipment used * GEOCON INCORPORATED 2.5 Where the slope ratio of the original ground is steeper than 6.0 horizontal to 1.0 vertical, or where recommended by the Soil Engineer, the bank should be benched in accordance with the following illustration. NOTES FINISH GRADE SLOPE TO 3E SUCH THAT SLOUGHING OR SLIDING DOES NOT OCCUR ORIGINAL GROUND REMOVE AS RECOMMENDED BY SOIL ENGINEER FINISHED SLOPE SURFACE KEY 3 (NOTE I) (NOTE 2) (1) "B" should be 2' wider than the compaction equipment, and should be a minimum of 10* wide. (2) The outside of the bottom key should be below the topsoil or slopewash and at least 3' into dense forma- tional material. 2.6 After the areas have been plowed or scarified, the surface should be disced or bladed until they are free from large clods; brought to the proper moisture content by adding water or aerating; and compacted as specified in Section 4 of these specifications. 3. Materials Suitable for Use in Compacted Fill 3.1 Material that is perishable, spongy, contains organic matter, or is otherwise unsuitable should not be used in compacted fill. Material used for compacted fill should consist of at least 40 percent fines smaller than 3/4-inch diameter. 3.2 3.3 3.4 The soil engineer should decide what materials, either imported to the site or excavated from on-site cut areas, are suitable for use in compacted fills; the Soil Engineer should approve any import material before it is delivered to the site. During grading, the contractor may encounter soil types other than those analyzed for the soil investigation. The Soil Engineer should be consulted to evaluate the suitability of such soils. Any material containing rocks or hard lumps greater than 6 inches in diameter should be placed in accordance with Section 6 of these _ n -?SpGC -T-T t^- X *—-a. i_ J-W no • The Soil Engineer should perform laboratory tests on representative samples of material to be used in compacted fill. Such tests should be performed to evaluate the maximum dry density and moisture content of the samples. The tests should be performed in accordance with accepted test methods of the American Society of Testing and Materials (ASTM) . GEOCON INCORPORATED 4. Placing, Spreading, and Compacting Fill Material 4.1 Unless otherwise specified, fill material should be compacted while at a moisture content near the optimum moisture content and to a relative compaction of at least 90 percent as determined by accepted ASTM test methods. 4.2 Fill materials should be placed in layers that, when compacted, have a relative compaction in conformance with the project specifications. Each layer should be spread evenly and mixed thoroughly to provide uniformity of materials in each layer. 4.3 When the moisture content of the fill material is less than that recommended by the Soil Engineer, water should be added until the moisture content is as recommended. When the moisture content of the fill material is more than that recommended by the Soil Engineer, the fill material should be aerated by blading, mixing, or other methods until the moisture content is as recommended. 4.4 After each layer is placed, mixed, and spread evenly, it should be thoroughly compacted to the recommended minimum relative compaction. 4.5 The fill should be compacted by sheepsfoot rollers, multiple-wheel pheumatic-tired rollers, or other types of compacting rollers that are capable of compacting the fill at the recommended moisture content. Each layer should be rolled continuously over its entire area until the recommended minimum relative compaction is achieved throughout the fill. 4.6 The fill operation should be continued in layers, as specified above, until the fill has been brought to the finished slopes and grades shown on the approved plans. 4.7 Fill slopes should be compacted by sheepsfoot rollers, by track- walking with a dozer, or by other suitable equipment. Compaction operations should continue until the slopes are properly compacted (that is, in-place density tests indicate a relative compaction of at least 90 percent at a horizontal distance of 2 feet from the slope face) . 5. Observation of Grading Operations 5.1 The Soil Engineer should make field observations and perform field and laboratory tests during the filling and compaction operations, so that he can express his opinion whether or not the grading has been performed in substantial compliance with project recommendations. 5.2 The Soil Engineer should perform in-place density tests in accordance with accepted ASTM test methods; such density tests should be made in the compacted materials below the disturbed surface. When results of tests taken within any layer indicate a relative compaction below that recommended, that layer or portion thereof should be reworked until the recommended relative compaction is obtained. GEOCON INCORPORATED 6. Oversize Rock Placement 6.1 "Oversize" rock is defined as material that is greater than 6 inches and less than 4 feet in maximum dimension. Material over 4 feet in maximum dimension should not be used in fills; such material should be exported from the site, broken into acceptably sized pieces, used for landscaping purposes, or placed in areas designated by the Soil Engineer and/or approved by appropriate governing agencies. 6.2 The Soil Engineer should continuously observe the placement of oversize rock. 6.3 Oversize rock should be placed in lifts not exceeding the maximum dimension of the rock, and should be placed in a manner that will not result in "nesting" of the rocks. Voids between rocks should be completely filled with properly compacted (minimum relative compaction of 90 percent), fine granular material. 6.4 Oversize rock should not be placed within 5 feet of finish pad grade, within 10 feet of street subgrade, or within 2 feet of the bottom of the proposed utility lines, whichever is deeper. 7. Protection of Work 7.1 During construction, the contractor should grade the site to provide positive drainage away from structures and to prevent water from ponding adjacent to structures. Water should not be allowed to damage adjacent properties or finished work on the site. Positive drainage should be maintained by the contractor until permanent drainage and erosion control facilities are installed in accordance with project plans. 7.2 No additional grading shall be done, except under the observation of the Soil Engineer. GEOCON INCORPORATED t-ocanwi or TEST tomm ^> A»«a». LOOTIOB or T Oa/ aunn Of TC1I*4CC OCFOStTI Td DC JSO S*»T>*«o •€«« VOLCAmCS orwrnimjHC TV« OKA •HOMIOK CALOXXTVN STAGECOACH PARK S!TE_ File No. D-3480-J01 September 20, 1985 FINISH GRADE 40 MIN. r.rT.Mr. GROUND. SURFACE /Jl NOTE 3 ' qi IDEPLANE NOTES: 1. Base of shear key to be 2 feet minimum below slide plane and 40 feet minimum in width. 2. Shear key material to be properly compacted granular material. 3. Backslope and front slope to be 1.0 to 1.0 or flatter, 4. If subdrain required drain shall be 4-inch minimum perforated ABS or PVC pipe sloped to drain to convenient outlet. Pipe to be surrounded by Class II permeable material (CalTrans Specifications Section 68-1.025) extending at least 5 feet above slide plane or seep, whichever is higher. STAGECOACH PARK CARLSBAD, CALIFORNIA Figure 1 GEOCON INCORPORATED