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Home My WebLink AboutCT 81-16; Vista Santa Fe Phase A; Soils Report; 1983-10-05-- LEIGHTON kxl ASSOCIATES - - - - - SOIL ENGINEER1 NG TESTING GEOLOGY October 5, 1983 TO: ATTENTION: SUBJECT: ENVIRONMENTAL SCIENCES Project No. I83060 I -02 Polygon Corporation c/o Russell Padia 1234 Normandy Place Santa Ano, California 92705 Mr. Russell Padia, Project Manager Grading Plan Review and Supplemental Geotechnical Investigation for Phase A, Vista Santa Fe and Commercial Area SE-17, Vista Santa Fe, Portions of Carlsbad Tract 81-16, City of Carlsbad, California In accordance with your authorization, we have conducted a supplemental investigation and a groding plan review of the above-referenced site. The accompanying report presents the results of our review and investigation. Following a brief introduction, we present our conclusions and recommendations. If you have any questions regarding our studies, please contact us. RECEIVED C~‘I- 111983 C!TY OF CARLSBAD ENGXERING DEPARTMENT JHH/LC/IP/dh Respectfully submitted, LEIGHTON AND ASSOCIATES, INC. Project Engineering Geologist lraj Poormand, RCE 20968 ’ Chief Geotechnical Engineer . Distribution: (3) Addressee (3) Rick Engineering Attention: Mr. Barry Render 1151 DURYEA AVENUE. IRVINE. CALIFORNIA92714 17141 555-1421 . l213, 6912125 lR”lNE s WESTLAKE,“ENT”RA . DIAMOND BAR/WALNUT. SAN BERNARDINO,RI”ERSIDE. 5aN DlEGO . PALM DESERT - TABLE OF CONTENTS Section - 1 .O INTRODUCTION AND PURPOSE I. I Scope of Investigation 1.2 Proposed Development 1.3 Site Description 2.0 FINDINGS AND CONCLUSIONS 2.1 2.2 ::i 2.5 2.6 zi ::;o Earth Materials Landslides Ground Water Settlement Considerations Slope Stability 2.5. I Landslides 2.5.2 Cut Slopes and Fill-Over Cut Slopes 2.5.3 Fill Slopes 2.5.4 Offsite Future Planned Cut-and-Fill Slopes Earthwork Shrinkage Excavation Characteristics Expansive Soil Characteristics Erosion Final Conclusions 3.0 RECOMMENDATIONS ::: General Earthwork and Grading Specifications Removals 3.2. I General 3.2.2 Phase A 3.2.3 Area SE- I7 3.3 Slope Stability 3.4 Z:Z 3.7 3.8 EO 3:1 I 3.12 3.3.1 Cut Slopes and Fill-Over-Cut Slopes 3.3.2 Fill Slopes 3.3.3 Surficial Slope Stability Subdrainage Lot Capping Foundations and Slobs Lateral Earth Pressures Type Cement for Construction Surface Drainage Graded Slopes Final Grading and Construction Plan Review Geotechnical Testing and Observation During Grading Page I : 18 18” 1’9 I9 i LEIGHTON and ASSOCIATES ,NCORPORATED - ~.- - - - - _- - - -- TABLE OF CONTENTS (Cont’d.) LIST OF ILLUSTRATIONS AND APPENDICES Index Map of the Polygon Corporation Project Area Plates Plate IA - Geotechnical Map of Phase A - North Half Plate IB - Geotechnical Map of Phase A - South Half Plate 2 - Geotechnical Map of Commercial Area SE-17 Plate 3 - Proposed Canyon Dewatering Trench Drain Cross-Sections A-A’ through K-K’ Cross-Sections SE-I 7 A-A’ through SE- I7 C-C’ APPENDICES A - References B - Boring and Trench Logs C - Summory of Laboratory Test Data D - General Earthwork and Grading Specifications E - Table of Major Cut Slopes and Fill-Over-Cut (Transition) Slopes F - Table of Anticipated Transition Lots G - Stability Analysis H - Homeowner’s Guidelines for Slope Maintenance ii & 2 In Pocket In Pocket In Pocket In Pocket In Pocket In Pocket LElGHTON and ASSOCIATES lNCORPORATED 1.0 INTRODUCTION AND PURPOSE This report has ~been prepared at your request and authorization and summarizes the results of our investigation and grading plan review. The purpose of this study was to evaluate the geotechnical conditions at the site and to relate these conditions to the proposed grading and development of an area designated as Phase A and a commercial site designated as Area SE-17 (both are portions of Carlsbad Tract 81-16). See Page 2 for Location Map. The 30-scale grading plan and the IOO-scale tentative map prepared by Rick Engineering dated June 1982 were reviewed and evaluated in light of the geotechnical conditions encountered at the site. The 30-scale grading plan sheets for the Phase A prea were spliced together and then cut into two segments and these are included in the pocket of this report OS Plates IA and IB. Plate 2 comprises a portion of the IOO-scale map showing tentative grading of Commercial Area SE-I 7. The geotechnical data gathered during this investigation and the geotechnical data from work by others were transferred to these grading plan base maps. Landslide areas and proposed cut slopes and fill-over-cut slopes have been designated by numbers on the accompanying geotechnical maps, the cross-sections and the accompanying tables. The approximate areal distribution of surficial materials and the underlying bedrock materials are included on the accompanying maps. I. I Scope of Investigation - I. 2. 3. 4. - 5. 6. 7. . 8. 9. - IO. - Review of previous reports and maps by others (see Appendix A, References). Review of stereoscopic pairs of vertical aerial photographs flown on July 13, I960 and November 9, I970 (see Appendix A, References). Geotechnical mapping of the site. Preparation of dozer access roads and drilling pads. Excavation, sampling, detailed geologic logging and backfilling of I I borings (see Appendix B). Excavation, sampling, detailed geologic logging and backfilling of I3 backhoe trenches (see Appendix B). Soil engineering laboratory testing (see Appendix C). Evaluation and analysis of collected data, including analysis of existing alluvial areas and slope stability analysis in light of the proposed development. Preparation of this report, including the geotechnical illustrations. Meetings and consultations. LEIGHTON and ASSOCIA,TES INCORPORATEO - - -. _~ - - - .- - -~ - - - - - - 18 VISTA SANTA FE CARLSBAD, CALIFORNIA FOR POLYGON CORPORATION (SUBJECT AREAS SHOWN IN YELLOW) BASE MAP: USGS 7.5 Minute Quadrangles, Encinitas and Rancho Santa Fe 1.2 Proposed Development - Phase A is~ planned primarily os a residential development of single-family homes. Improvements associated with development of Phase A include the widening of Rancho Santa Fe Road, construction of D detention basin in the main drainage course and. construction of an access road (“A” Street) to the project from Roncho Santa Fe Road across the main drainage course. A balanced cut and fill operation, consisting of approximately 312,000 cubic yards, is planned. Major fills are proposed along the southeast margin of the main drainage course. Area SE-17 is o proposed commercial area adjacent to Rancho Santa Fe Road. Tentative grading plans indicate construction of a large fill slope along the margin of the main canyon with cuts adjacent to Rancho Santa Fe Road resulting in a “flat” building area. 1.3 Site Description - Both Phase A and Area SE-17 consist of generally gently sloping hillsides, flot- topped, with slopes predominantly flatter than 3:1 (horizontal to vertical). The flat- topped hills may be related to terracing, landsliding, or both. The main drainage course transecting Phase A and along the margin of Area SE-17 is broad and nearly flat. Vegetation on the site is predominontly thin grasses and shrubs with occasional larger shrubs and small trees in the main canyon. Barbed-wire fences, corrals and other structures associated with cattle ranching are also present. - - - - - -3- - - - - -~ - -, - .- - - - - 2.0 FINDINGS AND CONCLUSIONS - Based on our review of the groding plans and our supplemental investigation, the general conclusions, OS well OS specific conclusions relevant to the proposed grading for Phose A and Area SE-17, ore OS follows: 2. I Earth Moteriols l The Del Mar Formation bedrock - The bedrock underlying the site con be charocterized as follows (see also Plates I A, I B, and 2, the Cross-Sections and Appendix B, Boring ond Trench Logs): a b. C. d. e. It is composed primarily of siltstone and claystone with lesser sandstone. The siltstone and claystone materials are generally very moist to wet and stiff to very stiff ond generally moderately to highly expansive. The Del Mar Formotion is weathered severely, dry to damp, with large desiccation crocks within the upper several feet ond, therefore, may require stripping/ removal deeper than normal benching for fills which ore to be placed over existing hillsides. The sandstone occurs OS both lenses and beds of varying thickness from 0 to 102 feet. Due to the mode of deposition, the sandstones occur irregularly on the site. For purposes of potential mining of the sandstone OS select material, we consider the sand to occur unpredictably and, thus, should not be relied on OS o source. Bedding planes ore generally irregular, poorly developed and sparse. Bedding dips generally less than IO degrees, OS measured from the horizontal. Dip direction was vorioble across the site owing to the low angle of dip coupled with broad regional worping ond tilting. There is a generol indication of o south and southwesterly inclination to bedding. Numerous wide, diffuse zones of shearing, OS well OS more well-defined zones of sheoring ore present in the bedrock and con be considered potential sources of slope instability. Numerous landslides and possible landslides ore present in both Phase A and Area SE- 17. . Overburden/Surficial Units cr. Alluvium: Alluvium, o stream-deposited sediment, is present within the main drainage course in both Phase A ond Area SE-17, and generally consists of sandy cloy and silty cloy. The moximum depth of the alluvium is approximately 30 feet within the moin droinage course. The materials ore wet and compressible. Treotment of this moterial will be required prior to fill placement. -4- - - -~ - .- - - -5- b. C. d. Colluvium: Colluvium is a thick overburden of soil which hos accumulated to o thickness of 4+ feet ond greater by o combination of deep weathering and slope wash. Colluvium is generally silty cloy and sandy cloy and moderately compressible and exponsive. A thick colluvial or questionable old landslide material is present in Area SE-17 where thick fills ore proposed. This moterial is also considered moderately compressible and will require ot least partial removal prior to receiving fill. w The site is over loin by (I cover of clayey topsoil which ranges in t rc ness from I to approximately 5 feet. This topsoil is generally expansive and compressible. Stripping/removal of this materiol will be required prior to fill placement, where normal benching will not remove this material. Existing Fill: Existing fill associated with the Ranch0 Santa Fe Rood fill prism is present along the northwesterly margin of both Phase A and SE-17. The nature of removals or ground preparotion beneoth the fill is not known. Minor, uncontrolled fill is present locally within the site and will require removal prior to fill placement. 2.2 Londslides Our anolysis indicates the presence of possible deep-seated landslides, OS well as shallower landslides. a. The landslides appear to be better charocterized OS bedding plone failures rather than rotational, slump-type failures. Rupture surfaces are generally poorly defined. b. The landslides oppear to hove moved more or less intact with minimal internal disruption. c. Craben development at the heads of the slides appears to be minimal without deep, highly weathered, and poor-quality deposits; or, alternatively, erosion moy hove stripped much of the slide material and the remaining remnants ore without large graben development. Some compressible graben materials may be encountered during groding, however. d. The deeper-seoted landslides appeor to toe out beneath the alluvium, having moved prior to alluviation when a sharply incised canyon was present. These slides appear to be effectively buttressed by the present alluvium. 2.3 Ground Water Q. Ground water is present throughout the main conyon bottom. Long-term levels appear to fluctuate seasonally and annually. At the time of our investigation, ground water wos at o depth of about 2-3 feet beneath the existing canyon grade ond surface flow WQS present. - - .- - - - - .- - - b. Occasional seeps were noted in the bedrock at shear zones and very commonly at the base of sandstone units. Notable seepage was present in Boring B-IO in Area SE- 17. Settlement Considerations General: The undisturbed bedrock underlying the majority of the site has very low compressibility characteristics, and settlement of these materials is not anticipated to be a concern. However, the landslide debris, overburden topsoil, colluvium and alluvium are slightly to highly compressible, and settlement of these materials, under fill loading, will occur unless mitigation measures are undertaken. Overburden-Topsoil and Colluvium: The overburden topsoil and colluvium on the natural slopes at the site are oenerallv comoressible and will reauire removal orior to fill placement to prevent-significant settlements. Where’ the compre&ible overburden is shallow, less than approximately 4 feet and slopes are steeper than 5:1 (horizontal to vertical), the overburden can be benched out during conventional fill placement operations. However, the thickness of compressible overburden on the sideslopes of several areas at the site is greater than can be conveniently removed by benching and much of the site is flatter than 5:1 (horizontal to vertical), and, thus, overexcavation/stripping will be required. Landslides: Where the landslide mass is disturbed, broken and highly weathered as a result of slide movement, the slide material may not support proposed fills without undue fill settlement. That is, open structures in the slide debris, or highly weathered slide debris (upon future moisture infiltration), could be closed by the weight of the fill, resulting in ground settlement. Where exposed during excavation, removal of unsound portions of the slide mass will be necessary. It is anticipated that open-structured slide material will be confined largely to the graben or head scarp and toe areas of the landslides. Overexcavation or benching into all landslide debris will be necessary to allow for inspection and evaluation. Recommendations for treatment of landslide debris are discussed further in the “Recommendations” section of this report. Alluvium: Alluvial materials, present along the main drainage course in both Phase A and SE-17, are generally compressible. If the proposed fill embankments are placed in these areas without treatment of alluvial deposits, detrimental settlement will occur. Therefore, overexcavation and recompaction of compressible alluvial materials will be required prior to fill placement. However, due to the existence of surface water and high ground water levels, complete overexcavation of the alluvial deposits, which extend to depths of approximately 30 feet in the main drainage course, is not considered practical. Settlement computations indicate that the proposed fill in the main drainage course, without any removal, may induce settlements up to I foot. With the removal of the upper IO feet of the alluvial deposits, the total settlement would be reduced to 6 inches or less. Vertical permeability of the alluvial material is considered low, but horizontal permeability (due ta the presence of frequent layers of coarser alluvium) is comparatively high. Specific recommendatibns for treatment of the alluvium are presented in Section 3.0, “Recommendations”. The recommendations include special provisions to take advantage of the higher horizontal permeability and accelerate the settlement process. - - 2.5 Slope Stability 2.5.1 Landslides - ,- - - In general, the proposed grading will provide the necessary stabilizing effect for the landslides toeing into the main canyon due to the placement of significant quantities of fill materiol at the toes of these landslides and/or the removal of driving forces by unloading/cutting the heads of the slides. A typical slope stability analysis performed on Cross-Section SE-17 B-B’ is presented in Appendix G. However, Landslide I, located in ~Commercial Site SE-17, will require a deep shear buttress. Additionally, cut slopes and fill slopes proposed within the slides will require remedial treatment, as discussed below. 2.5.2 Cut Slopes and Fill-Over-Cut Slopes Stability analyses indicate that the proposed cut slopes will be stable against deep-seated failure if adverse geologic or soil conditions do not occur in the slopes. Where adverse conditions are exposed, replacement or buttress fills would be required to provide stable slope conditions. The Table of Major Cut Slopes and Fill-Over-Cut Slopes in Appendix E describes the anticipated geologic conditions and our conclusions and recommendations for slopes generally IO+ feet or greater in height. These slopes are shown on Plates I A, I B and 2 and on the cross-sections. 2.5.3 Fill Slopes The predominant materials anticipated for use in fill slope grading will consist of sandy clays to silty clays. Stability analyses indicate that proposed fill slopes comprised of these materials will be stable against deep-seated arcuate failure provided they are constructed in accordance with the recommendations of this report. - 2.5.4 Offsite Future Planned Cut-and-Fill Slopes Special considerations should be given to both fill and cut slopes constructed along and near ihe margin of Phase A and SE-17. This is to assure that proposed future offsite grading is duly considered at this stage of develop- ment, and to avoid either regrading in the future or future slope stability concerns to Phase A and SE-17 from future offsite improvements. These areas are discussed in Section 3.3 of the Recommendations and Appendix E. - 2.6 Earthwork Shrinkage The volume change of excavated on-site materials upon recompaction as embankment fill is expected to vary with materials and location. The soil and bedrock materials vary in natural and maximum density, and accurate, overall determination of in-place and compacted density cannot be made. Therefore, accurate earthwork shrinkage estimates cannot be determined. However, the following shrinkage values are provided as guideline estimates: l!lw 4 - - - .- - l Alluvium: I5 to 20 percent shrinkage 0 Colluvium: 5 to I5 percent shrinkage . Bedrock materials: 3 percent bulking to 3 percent shrinkage . Surface material subsidence: .2 feet to .4 feet 2.7 Excavation Characteristics The prevailing materials at the site will generally be rippable using conventional heavy earthmoving equipment. The majority of alluvium and some portions of colluvium is expected to be wet, and special equipment (drag line, large backhoe, swamp cats, or a combination of the above or others will probably be needed. - 2.8 Expansive Soil Characteristics - The soils at the site which will be involved in grading will generally vary in swell characteristics from low to very highly expansive. The soils occurring at finish grade subsequent to finish grading are anticipated to be predominantly moderately to highly expansive. - 2.9 Erosion - -~ - - - - - - The subject property occurs in an area of Mediterranean climate, characterized by winter precipitation maxima and summer dry periods. Intense winter storm periods occur every few years, with the years 1938, I96 I, 1969, 1978, 1979, I980 and 1983 representing recent years with particularly damaging storm periods. Heavy rainfall impacting on bare soil is able to move many tons of soil per acre during average storm periods, and is even more effective if the soils are previously wet. In addition to climatological factors, the character of earth materials plays a prominent role in determining the amount of erosion that will occur during individual storms or on a long-term basis. Clayey surficial soils, such as those that occur on the site, expand when wet and then shrink and crack upon drying. Cracking allows rapid infiltration of water from subsequent storms, repeating the process at greater depth and ultimately resulting in the loosening of surficial soils. This increases their erodibility and susceptibility to saturation and failure en masse where these soils occur on steep slopes; to a lesser degree, gullying, piping, and accelerated erosion can be expected on steep to moderately steep slopes and where surficial deposits are thick. In general, the erosion potential at this site is considered moderate, and provisions for site drainage, sediment retention structures, terrace drains, slope plantings and other measures in accordance with the City of Carlsbad Grading Ordinance should afford adequate protection. Local areas may require additional measures at the discretion of the soils engineer during grading. -8- - - 2. IO Final Conclusions - - Based on our investigation, review of previous geotechnical data, analyses and review of the grading plan, it is our opinion that the subject site can be developed safely from a geotechnical viewpoint, provided the recommendations of this report are implemented during rough grading and other related phases of construction. - Area SE- 17: Due to the tentative nature of the IOO-scale grading plan available at this time, the conclusions, as well as the following recommendations pertaining to Area SE- I7 must be considered tentative at this point and subject to further review. - - - - - - -9- - - 3.0 RECOMMENDATIONS - 3.1 General Earthwork and Grading Specifications - Prior to commencement of grading operations, all vegetation should be cleared and disposed of off-site. All areas to be filled should be moisture-conditioned, scarified and/or overexcavated and recompacted to at least 90 percent relative compaction prior to fill placement. Grading should be accomplished in accordance with the recommendations of this report and the General Earthwork and Grading Specifica- tionspresented in Appendix D, unless specifically revised or amended below. - - - - - - - - 3.2 Removals 3.2. I General Overexcavation of compressible overburden materials will be required during grading prior to fill placement thereon, as discussed in Section 2.4 of this report. The overexcavated materials should be moisture-conditioned (moisture added, soils dried or blended as necessary) and recompacted as structural fill in accordance with the recommendations of the General Earthwork and Grading Specifications (see Appendix D). The actual depth and extent of required removals would be determined during the earthwork operations, based on in-grading inspections. However, estimated removals are discussed below for Phase A and the Commercial Site, SE-17. 3.2.2 Phase A a. Alluvium: Removal of alluvium is recommended for construction of the fill-over-cut slope (Slope Reference I I) along Ranch0 Santa Fe Road, the fill slope north of Slope I I (Sta. I31 -1343, along Ranch0 Santa Fe Road, a portion of “A” Street, the retention basin embankment located at the southwest corner of the site and the fill slope and pads located along the southeastern portion of the main drainage course. Due to the existence of surface water and the high ground water level, complete or deep removal of the compressible, saturated, fine-grained alluvium which extends to depths of more than 30 feet is not practical. The approximate thickness of the recent alluvium to be removed is expected to be 7 to IO feet. The limit of removal will be approximately 30 feet outside the toe of the proposed fill slopes, except for the fill-over-cut slope (Slope II) and the fill slope (Sta. I31 -134:) along Ranch0 Santa Fe Road, where the limit will be approximately IO feet outside the toe of slope with a removal depth of approximately 5 feet. (See Cross-Section D-D’.) A typical detail of alluvial removal is shown on the sketch on Plate 3 and on Cross- Section F-F’. The majority of the alluvium is expected to be wet, and special equipment (drag line, large backhoe, swamp cats, or a combination of the above or others) will probably be needed. - IO - - - - - -~ - - - - - - - - - - It is anticipated that installation of a l2- to l5-foot deep, gravel-filled trench, approximately at the middle of the large alluvial strip to be removed (see Plate 31, will facilitate alluvium removal and will accelerate the settlement process associated with subsequent fill loading of the area. The excavated wet alluvium will have to be spread, air-dried, mixed with drier onsite materials, or a combination of those methods, prior to fill placement. It may be necessary to remove the wet alluvium in sections and replace it with granular material before moving to the next removal section. A layer of granular material should be placed in the bottom of the excavation once the wet alluvium has been removed. This granular layer should be a minimum of 2 feet thick, but should not exceed 6 feet in thickness. Because of the wet ground conditions anticipated, the thickness of the granular layer may have to be greater than 2 feet in order to provide drainage and firm ground on which heavy equipment can work. The compacted fill may pump during the initial stages of backfilling. The source of this granular material will probably be the Torrey Sand, upslope and offsite of the Phase A grading. Special planting, lime treatment or equivalent measures should be considered to minimize the potential for wave erosion along the toe portion of the slopes during times of water impoundment. Existing surface water will have to be diverted around the area of removal, and dewatering efforts will be necessary. The approximate location and detail of the dewatering trenches are shown on Plate 3. Dewatering systems and pumps, in addition to the recommended sumps, may be necessary to minimize water entering the excavation. It is estimated that the total time-dependent settlement induced by the proposed fill placed over the left-in-place compressible alluvium is on the order of 6 inches or less. It is anticipated that approximately one-half of the total settlements will occur during fill construction. Settlement monuments should be installed upon completion of rough grading to monitor the settlements. Approximate locations of the monuments are shown on Plates A-l and A-2 (total of six, four on the edges of pads, one on the retention basin embankment, and one on “A” Street). A survey of these monuments will be needed periodically until settlement has essentially been completed (approximately 6 months to one year). Surcharge: Utility lines may have to be installed earlier at the portion of “A” Street, and it is recommended that this portion of the street be surcharged to accelerate the settlement process. The minimum thickness of the surcharge fill will be IO feet. The approximate location of the surcharge fill is shown on Plate I A. The outer edges of lot pads that are adjacent to the alluvial-filled drainage course should be increased by approximately 6 inches (for 502 feet in width) in order to provide for anticipated settlement in this area. It is recommended that the proposed fill be placed in this area as early as practical to allow for earlier completion of the settlement process. - II - b. C. - - - - - ,- -~ - - .- d. 3.2.3 & ‘ea SE-I 7 a. Alluvium: Removal of alluvium is recommended for the construction of the overlying fill slope. The approximate thickness of the removal is expected to be 7 to IO feet. The limit of removal will be approximately 30 feet outside the toe of the proposed fill slope, as shown on the sketch on Plate 3. A 2- to 6-foot thick layer of granular material, probably from the Torrey Sand, would be needed; similar to that planned for Phase A. Special equipment for excavating wet material probably will be needed. Understructures: The drainage culverts under “A” Street and the under- structure for the retention basin embankment should be installed after complete settlement has occurred or the design should consider tolerance for the remaining potential settlement. Due to the time constraint, it is recommended that the structures will be precast RCP having sections no longer than 8 feet, or equivalent material ~which can tolerate grade adjustments. The same concerns/considerations (flexible system/cambers, etc.) are applicable for utility lines planned for the portion of “A” Street. Colluvium: In general, the colluvial soils (geologic map symbols, COI, mhthe site (Plates IA and IB) should be removed to firm bedrock prior to fill placement. It is anticipated that these removals will extend to a maximum depth of about IO- feet. If other areas underlain by colluvial soils are exposed during grading, they should be similarly treated. The upslope portions of the colluvium material can probably be excavated with conventional equipment. Downslope portions of the colluvium that exist in proximity to the alluvium will probably be wet and require special equipment similar to that used to remove the wet alluvium. Landslides: In general, the shallower portions of the slide areas should be stripped to a depth of approximately 4 feet. The actual depth of stripping should be determined during grading based on field inspection. In addition, normal benching (approximately 4 feet in height) should be performed during fill placement. The slide material can be removed with conventional earthmoving equipment, and the excavated slide material could be used for backfilling. Landslide removals related to the stability of the proposed cut, fill-over- cut and fill slopes are anticipated. They are discussed separately under the slope stability portion of the recommendations, Section 3.3. Areas to receive fill which are on slopes flatter than 5:l, where Topsoils: normal benching would not completely remove the topsoils, should be stripped to firm bedrock material, prior to fill placement. Topsoil is expected to be generally between I and 5 feet thick, locally. Final recommendations will be made when a more detailed map of this area is available for reviewing. Settlement monuments (two) should be installed at approximate locations as shown on Plate 2, upon completion of rough grading to monitor the settlement which is estimated to be on the order of 6 inches total. Survey of the monuments wilt be performed monthly until settlement has been completed. It is recommended that the proposed fill be placed in this area as early as practical so t will be substantially complete as early as possible. - ,- - .- - - - - - .- b. Colluvium or questionable landslide material (Mop Symbol COI or Qls? see also Plate 2): Removals rn this areil should extend to tirm be %EG material or to a maximum depth of IO feet, subiect to field inspection. In any event, creep-affected materials on the relatively steeper areas at higher elevations should be removed. c. Londslides: Landslide reference ~nurnbers relate to the numbered landslides shown on Plate 2. . Landslide I: Removals necessary for the support of the proposed fill embankments are discussed later in this section under “Slope Stability”. Normal benching is expected to remove unsuitable surficial materials during fill placement, subject to field verification. . Landslide 2: Possible removals related to stability of the cut slope on the north side of Mision Estancia are discussed under “Slope Stability”, Section 3.3. . Landslide 3: This large, questionable landslide is not anticipated to require removals, except the removal of near-surface topsoils and the uppermost highly weathered bedrock estimated to be from 2 to 6 feet thick, typically 4 to 5 feet thick. . Landslide 4: --- Compressible soils are anticipated in this area. Removals to as much as IO feet may be necessary. 3.3 Slope Stability 3.3. I Cut Slopes and Fill-Over-Cut Slopes Appendix E includes the geologic conditions, conclusions and recommendations for each of the major cut and fill-over-cut slopes. To summarize, Slopes I, 4, 7, 8, 9A and 98 of Phase A ore considered possibly unstable as designed and the requirement of remedial treatment will be determined during grading based on field inspections, and Slopes 2, 3, 5, 6, 9C, IO, I I and 12 of Phase A and I and 2 of SE-I 7 are considered probably unstable as designed. Slope I I is discussed in Appendix E and fin Section 3.2.2.a. A buttress having a key width of 20 feet, a key depth of 5 feet and an approximate I%:1 backslope is recommended for each of these slopes, except IOB and 12. A buttress having o key 15 feet wide and 5 feet deep, or a layback, is recommended for Slope IOB (Cross-Section I-I’). A deep key (estimated ot 13’3 is recommended for Slope I2 (Cross-Section E-E?. Approximate locations of the buttress keys are shown on Plates IA, IB and 2 for the slopes considered probably unstable as designed. Larger buttresses may be required, based on in-grading inspections. Some of the keys may have to be built in sections, where determined by the geotechnical engineer during the course of grading, to minimize the potential for backslope failure. Probably unstable Slopes 9C, IO and I2 ore along the periphery of Phase A, adjoining future .offsite grading within the proposed Vista Santa Fe development, and are within ancient landslides. As discussed in Appendix E, we strongly recommend that remedial measures taken for these slopes consider the future offsite development. The recommendations are based on assumed and tentative finol offsite grades, as shown on Cross-Sections E-E’, H-H’ and l-l’. The design engineer .should verify these final grades. Significant deviotion from the assumed grades could necessitate additional future work to provide adequate stability. Kl an - I3 - LEIGHTON and ASSOCIATES INCORPORATED - - - - - - - - .- - - In addition to the slopes listed in Appendix E, some low between-lot slopes moy prove unstable. These ore best handled on an individual basis during grading. Where fill-over-cut slopes ore not to be stabilized, the cut portion is to be constructed prior to fill placement to allow inqroding geologic inspections to evaluate slope conditions. Where the cut portion is low (less than 5 vertical feet), it should be undercut (I 5 feet wide) and the entire slope constructed OS o fill slope. 3.3.2 Fill Slopes Fill slopes shall be constructed in accordonce with Appendix D. Where removals, which were discussed in Section 3.2, are not sufficient to establish suitable support for the proposed fill slope, o base key should be excavated prior to construction of fill slopes and benching into firm material should be performed OS the fill material is placed. Q. Phase A: 1. 2. 3. 4. The fill slopes between Cut Slopes I and 2, and 2 and 5 hove toes locally within CI few feet of natural grade. Slopes will be constructed on colluvium/topsoil and landslide removal areas. The removals and normal benching to firm bedrock material will be required. The major proposed daylight fill slope ot the eastern limit of Phase A is situated at the heods of Landslides 3 and 6. Future offsite improvements show plonned fill-over-cut slopes from Lots 56 through 59. Remedial treatment for this area was discussed in Appendix E, Slope I2 (a buttress having o key width of 20 feet and o key depth of l3- feet below future adjacent grade is recommended). A shear key of normal dimensions (See Appendix D) will be required for the portion of the slope from Lots 60 through 64. As the notural grade is flatter thon 5:1 (horizontal to vertical), stripping will be required. The portion of the slope from Lots 65 through 68 is within the head of Landslide 6, just south of Slope 9C. Tentatively, o shear key having a key width of I5 feet ond o key depth of 5 feet is recommended. Additional removals may be required based on in-grading inspection. The doylight fill slope for “A” Street, on the northern perimeter of Phase A, is situated within Landslide 8 and alluvium. Removal of alluvium and slide material WCIS discussed eorlier. Additional removals beyond those discussed earlier ore not anticipated. The doylight fill slope below Lots I I I and 112, transitioning to the detention basin located at the southwest corner of the site, is expected to require normal keying and benching into firm bedrock if the topsoil layer, which will be removed, is less than 2 feet in depth. - - - 14 - LEIGHTON and ASSOClATiS INCORPORATEO - - - - - - - - - - - - b. Area SE-17: I. The sidehill daylighted fill slope in the area of Landslide I will require excavation to o depth of approximately I6 feet to establish a shear key. The approximate location of the key bottom is shown on Plate 2 and Cross-Section SE- I7 A-A’. 2. Removols discussed in Section 3.2.3 with regord to Londslide 4 ore considered sufficient to establish suitable support for the proposed fill slope at this orea. -. 3. The above recommendations and location of the shear key shown on Plote 2 ore tentative and subject to change based on the final grading plans. 3.3.3 Surficial Slope Stability Using the sheor strength parameters of 0 = 27’ and C = 250 psf for compacted fill, surficial stability analysis indicates that the proposed fill slopes will be surficially stable provided cohesionless material will not be used near the slope surface ond 90 percent compaction is achieved to the slope face. In addition, special planting or possible lime treatment could be considered to minimize the potentiol for wove erosion along the toe portion of slopes within the alluvial-filled drainage channel. During construction, special compaction procedures will be necessary in order thot the specified compaction con be achieved out to the slope face. Special procedures moy include sheepsfoot backrolling of the slope ot frequent intervols of slope height gain, overfilling and trimming bock to the compacted core, and/or other proven methods. 3.4 Subdrainage Subdrains should be installed in slope buttress and replacement fills, OS well OS bottoms of main drainoge courses, in accordance with the subdrain details presented in Appendix D. The opproximate locations of canyon drains for the four major reentrants in Phase A are shown on Plates IA and IB. In addition, o conyon dewatering trench drain is proposed for Phase A. The details ond opproximate location ore shown on Plate 3. For Area SE-17, in addition to subdrains for buttresses, Q buttress-type subdrain is recommended for the coIluvium/questionable landslide removal area, OS shown on Plate 2. Also, a canyon dewotering trench drain may be required for the olluviol removal area of SE-17. Final determination will be made when o detoiled grading plon for this ores is available for review. - I5 - LEIGHTON and ASSGClATES lNCORPORATED - - - - - - - - - - - - - - 3.5 Lot Capping It is recommended that all cut pads exposing unsuitable materials, such as highly fractured or weathered bedrock, landslide material or coIluvium/topsoiI, and the cut portions of transition lots (due to proposed cut/fill grading or recommended remedial work), be overexcavated a minimum depth of 30 inches to a minimum distance of 5 feet outside building areas and replaced with compacted fill in order to reduce the differential settlement potential on the proposed structures. Based on in-grading inspection, localized deeper overexcavation and recompaction of the unsuitable soils may be required. Appendix F lists lots which are shown on the grading plan (for Phase A) os transition lots. Additionally, we have shown other lots which we can identify at this time as possible transition lots depending on depth of removals, benching, etc. Tentatively, lot copping is recommended for all the cut pads of Area SE-17, as well as Mision Estancia. 3.6 Foundations and Slabs An allowable soil bearing pressure of 1500 psf may be used for conventional footings having a minimum embedment in approved material of I foot below the lowest adjacent grade and a minimum width of I foot. The bearing value may be increased by 500 psf for each additional foot of embedment in approved material and by 200 psf for each additional foot of width to a maximum of 3000 psf. ., It is anticipated that the soils occurring at finish grade will be predominantly moderately to highly expansive. Recommendations for both moderately and highly expansive soils are presented below. Additional expansion tests (Test Method UBC No. 29-2) will be performed after rough grading is completed, at which time final design recommendations will be submitted for each building. . Moderately Expansive Soils a. Foundations: Exterior footings for one- and two-story buildings should be continuous and founded I8 inches below exterior grade. Isolated or continuous footings may be used for interior bearing members and should be founded I2 inches below slab subgrades. Reinforcement in exterior and interior footings should consist of two No. 4 reinforcing bars, placed one at the top and one at the bottom. An l8-inch deep grade beam should be poured across the garage door openings and reinforced as for footings. b. Slabs: Living area slobs should be a nominal 4 inches thick (3% inches minimum), reinforced with 6x6-10/10 welded wire mesh located at mid-height. Living area slabs should be underlain by 4 inches of rounded gravel or clean sand and a 6-mil Visqueen moisture brrrier, plus an additional I inch of sand between the slab and Visqueen. Garage slabs should be a nominal 4 inches thick, reinforced with 6x6- I O/I 0 welded wire mesh or quartered, in lieu of mesh. Garage slabs should be isolated from stem and wall footings and underlain by 4 inches of crushed rock, gravel or clean sand. - I6 - LEIGHTON and ASSOCIATES INCORPORATED - - . High Expansive Soils - - - - .- - - - 0 - c. Presoaking beneath slabs: Living area and garage slab subgrade soils should be soaked to at least 1.4 times the optimum moisture content to a depth of 18 inches below slab subgrade prior to placement of concrete. The moisture penetration should be verified by the soils engineer. a. Foundations: Exterior footings for one- and two-story buildings should be continuous and founded 24 inches below exterior grade. Interior footings should be continuous and may be founded I2 inches below slab subgrade. Reinforcement in exterior and interior footings should consist of two No. 5 bars, placed one at the top and one at the bottom (or four No. 4 bars, two at the top, and two on the bottom may be utilized). Dowels consisting of No. 3 reinforcing bars should be placed at 36 inches on centers in the footings and bent 3 feet into the slab. A 24-inch deep grade beam should be poured across the garage door openings and reinforced as for footings. b. Slabs: Living area slabs should be a full 4 inches thick, reinforced with 6x6-6/6 welded wire mesh located at mid-height. Living area slabs should be underlain by 4 inches of rounded gravel or clean sand and a 6-mil Visqueen moisture barrier, plus an additional I inch of sand between the slab and Visqueen. Garage slabs should be a full 4 inches thick, reinforced with 6x6-6/6 welded wire mesh. Garage slabs should be isolated from stem wall footings and underlain by 4 inches of crushed rock, gravel or clean sand. c. Presoaking beneath slabs: Living area and garage slab subgrade soils should be soaked to at feast 1.5 times the optimum moisture content to a depth of 24 inches below slab subgrade prior to placement of concrete. The moisture penetration should be verified by the soils engineer. Post-Tensioned Slabs As an alternate to conventional foundation and slabs, buildings may be supported on past-tensioned slabs. The design should be performed by a structural engineer, in consultation with the geotechnical engineer. Living area slabs should be underlain by a 6-mil Visqueen moisture barrier covered by a I -inch layer of sand. In addition, presoaking, as recommended for conventional footings, is also suggested for post-tensioned slab systems. - I7 - LEIGHTON and ASSOCIATES INCORPORATED - - 3.7 Lateral Earth Pressures The recommended lateral earth pressures for the site soils are as follows: - Equivalent Fluid Weight (pcf) - Conditions Level Active 45 2:1 Slope 60 - - - - ,~- At-Rest 65 90 Passive 300 150 (sloping down) Unrestrained walls retaining l.5:l surcharged slopes should be designed for an equivalent fluid pressure of 85 pounds per square foot per foot of depth. Tom design an unrestrained wall, such as a cantilever wall, the active earth pressure may be used. For a restrained retaining wall, such as a basement wall, the at-rest pressure should be used. Passive pressure is used to compute lateral soil resistance developed against lateral structural movement. Further, for sliding resistance, the friction coefficient of 0.35 may be used at the concrete qnd soil interface. In combining the total lateral resistance, the passive pressure or the friction of resistance should be reduced by 50percent. The horizontal distance between foundation elements providing passive resistance should be a minimum of three ,times the depth of the elements to allow full development of these passive pressures. All retaining structures should be provided with a drainage blanket and weepholes or drain in order to assure that hydrostatic pressure will not build up. - - - 3.8 .Type Cement for Construction - Recommendations regarding cement type for use in concrete to be in contact with surface sails will be made based on soluble sulfate content tests to be performed on near-surface soils at finish grade. - 3.9 Surface Drainage Surface drainage should be controlled at all times. Residential structures should have eave drains and roof gutters to collect roof runoff. Positive surface drainage should be provided to direct surface water away from the structures, towards the street or suitable drainage facilities. Ponding of water should be avoided adjacent to the structures. Area drains should be provided in areas of decking and lawns. Positive drainage away from slopes must be maintained at all times. The need for drainage devices on the slopes is within the purview of the design civil engineer. - - - I8 - LEIGHTON and ASSOCIATES lNCc.RPORlTED - - .- - - - 3. IO Graded Slopes It is recommended that all graded slopes within the development be planted with ground cover vegetation (e.g., grasses) as soon as practical to protect against erosion by reducing runoff velocity, and with deep-rooted vegetation (e.g., trees and shrubs) to protect against surficial slumping by providing a deep root mesh. Inadvertent oversteepening of cut and fill slopes should be avoided during the fine grading and residential construction. t-tomeowners should be reminded of the responsibilities of hillside residents, i.e., the maintenance of proper lot drainage; the undertaking of property improvements in accordance with sound engineering practice, and proper maintenance of vegetation, including cautious lot and slope irrigation (see Appendix H, ~Homeowner’s Guidelines for Slope Maintenance). 3.1 I Final Grading and Construction Plan Review . Phase A - We have reviewed the final grading plans in conjunction with the preparation of this report. The conclusions and recommendations within this report have been incorporated in the final grading plans. The grading plans are approved from a geotechnical viewpoint subject to testing and inspection during grading. - - . Area SE-17 - In view of the tentative nature of the design, a geologic and soil engineering review should be conducted on the final grading and/or construction plan when it becomes available including comments on the expected effects of any major changes from the proposed grading on which previous recommendations were based. 3.12 Geotechnical Testing and Observation During Grading - - - Soil engineering inspections and testing should be conducted continuously during grading, and geologic inspections should be conducted periodically but continuously when necessary (see Appendix D). Preparation of a final geotechnical report that summarizes geotechnical conditions encountered during grading is recommended. This report should include an as- graded geologic map. - - - - - - I9 - LEIGHTON and ASSOCIATES INCORPORATED APPENDIX A - I83060 I -02 - .- I. - 2. - 3. - - -. - - APPENDIX A REFERENCES Shepardson Engineering Associates, Inc., I98 I, “Report of geotechnical investigation (Phase I), La Costa Areas SEI 8 thru SE2l”, prepared for the Meister Company, Job No. S.E.A. I IO 175, report dated April 2 I, I 98 I. --, 1983, “Report of geotechnical investigation, Phase II, proposed Vista Santa -_ Fe subdivision, Carlsbad, California”, prepared for Rick Engineering, Job No. S.E.A. I IO1 75, report dated June 8, 1983. Wilson, Kenneth Lee, 1972, Eocene and related geology of a portion of the San Luis Rey and Encinitas Quadrangle, San Diego County, California: Masters Thesis, University of California, Riverside, December 1972. AERIAL PHOTOS Year g&t Photo No. Approximate Scale Agency 7-13-60 T-2-SAC l-70, ~71 I”=1,000’ San Diego County I O-9-70 S.D. Co. 5-2 I-22 (color) I %2,000 San Diego County - - - - - - A-i APPENDIX B .- - - - - - MAJOR DIVISIONS SYIICOLS TYPICAL NAMES Its and organic silt clays y~rqam~~siltr, micaccaur or didtmacew* ine San y or elastic Silts CLASSIFICATIOti CHART (Unified Soil Classification System) . CLASSIFlCATIO!4 RWGE OF GRAIN SIZES ". 5. standard Grain size in sieve size n;,,imeters BOULDERS ABOVE 12" ABOVE 305 COBBLES 12" TO 3" 3051076.2 GRAVEL 3" TOllO.4 7G.2~04.7E COARSE 3" to ,,4" 76.2 to 19.1 FlNE vi" to NO.4 19.1 to 4.7b SAND No.4 TO 200 b.7GTO0.074 COARSE NO.4 to 10 4.76 to 2.~0 lEDI UM NO. 10 to 40 2.00 to 0.420 FINE NO. 40 to 200 0.420100.0,4 SILT & CLAY BELOW NO. 420 BELOW 0.074 GRAIN SIZE CHART 0 10 20 ,o 40 so 60 70 80 90 100 LlQUlD LlMlT PLASTICITY CHART METHOD OF SOIL CLASSIFICATIOt< ..~ - - - - - - - - - - - - - - - - GEOTECHNICAL BORING LOG DATE R-II-83 DRILL HOLE No. , SHEETIOFI PROJECT Q PROJECT No.1830(001-n~ DRILLING Co LQrive TYPE OF R~~b~~c~eta~~~aer HOLE DIAMETER .%" DRIVE WEIGHT 3700# fc 27.5’ /2500# b 55’ DROP - IN, ELEVATION TOP OF HOLES REF. OR DATUM see ~Q,D c ;; z:: IaD. z a = IO.? 09.1 IO.5 = - ub9 2; nz ;!i ‘3 = 9.; s u.2 8.1 - z-z y 2” -Iv; 5s = L- CH - -_ _- . <- GEOTECHNICAL DESCRIPTION ,.,c~.w.., s,~,,~,~*d,d,.,, Iwrc ,,t rvrk~c is" t) '@I' do&brown to black, very moist, plosh’c (very sop+), sandy clayi orga~ics @% varymol'st-we+. d-i&y thy, +r‘xecF layern’n9 ip cvt-kings; dive ckq chunk in cutkngs, ho.02 gravel 53 0' W&Y during drillin Q-T' coIo< chancjge -to orange brown;w&, becomes sandikr @9’ haav ‘I see p, IT-ace 3rcwel 10.8’ 241 PM q. 3’ 245 7.5 ’ 251 1.2’ 253 (a8’ 255 b.15’ 258 - - - - - - - ,- - - - - - - GEOTECHNICAL BORING LOG DATE A.I~,-R? DRILL HOLE No, 2 SHEET-• F.~ PROJECT Pol~oon! VI'S~~ Snntn Fe PROJECT,NO, IR~CX~OI-02 DRILLING Co. LQr;ve TYPE OF RIG~~PK~~ a~ HOLE DIAMETER 30" DRIVE WEIGHT 3700# Sn 27.5'/25OO'kb 55' DROP 12 IN, r ,,r't n-- ~. n.- ^^- .^^^_ In',-- .I,- -P c-n o- 7\ tLEVATION IOP OF HOI c w 3 3z:t _ .+/.I .- :Y Y-7 -i--- p44un.l .' _ 1.. : j -'..".' .',. b,NWl.uw .., ,... ,. -----i: C:N5jC,&" -. - -. - -- -.- IO- -'- -.- -. - -._ -.- -.- -.- GEOTECHNICAL DESCRIPTION Qs' reddish iron wide stainl'n I" silt Ixd, cnniinuoos around hole I Eh15' subhorizonfal shear dippl;)j west+ Cshenred tn 16') ClIiico'bedroclc is firm t 817.5’ rust c&red sil medium sand; massive, hard.~o rrectvrcd 'u- aiS' light ~~~~ge,somewhatGiable sI~~~~~wTxz medium sand; iron _ 820' somewhat cemented (irrcgukv czakzct~ Q21.1’ OIIVS pen sandy clayey siltstone EJ24' massive, less chyyey,~~sw~ 6lz.5' cmw-etiion C325.5' cnlor changeto da/Kxcq 'd"~;' _ silt; mass;< , mo<st, h rd short dlsconiinuous shear& 827' d-ear zone, rock broKenup, poll’shS~~,- Cnc”,. ,711 I FIG:HT”N P4 ASSOCIAITFS - ..- - - -- - - - - - - - - - - - GEOTECHNICAL BORING LOG DATE R-12-83 DRILL HOLE No. 2 SHEETLOFL PROJECTJ?+QQQ/ V&i-n %n-k~ !+ PROJECT No. 1~30(o01-53 DRILLING Co Lorive TYPE OF RIG h&d auk* HOLE DIAMETER 30" DRIVE WEIGHT 3-~00* 10 7~~5'!75oo#-tO~5 DROP L IN. ELEVATIC TOP of : H,,,F IbItt R c rnnO - u Eb- ;- : z aa au s-' " E t 0 -= LX -.a - -.. -.- -.- -. -.- -r.. - -.- @-=L:- _.- --.C.' _ -.- -.- -.-. -.- -.--' -.- -.- -.- -. --- .(j- ,- -. -.- -.- 5- EF, - z ;; 5: PL1 & P = 18.1 - ! DA - luEQ n . 25 “k gg 0 = 4.7 Y- OL 2; A i ,g = GEOTECHNICAL DESCRIPTION .OGGED BY sa/\~tiH SAMPLED BY snl.- 830' dQrl( blue-green, clay with numer~vs @31.5' base oc shearing zone, @32-33' change to blue 9'ay., moist, hard, clayey sil+ WI* sand; rn~~s?.~ve, unbroKcn,wwnidize~ a39 more shears ~btsl depth 41.5' I. m wakr 2 no caving a. sheared zone a+ 13.5' 4. sheared zone at 21-28.5' (germLIly G-mJ 5. firm shecwcd ZOM a+ 30-32' (a+ twp ~Funoxidiza zone) b. "m-y Firm, locall tj sheared a+ 39' 7. no dkii'nct, well- eveloped wp+urr surt"ac~ - - - - - - - - - - - - -~ GEOTECHNICAL BORING LOG DATE 8-10-83 DRILL HOLE No. 3 SHEET&OF-L- PROJECT Poh~on,/V~sSa SankxFc PROJECT No. -UO(OOI-02 DRILLING Co LariYC HOLE DIAMETER T” DRIVE WEIGHT TYPE OF RIG- 370%‘ +O z7.5’,i250b# fo 55 DROP IN, ELEVAT I( TOP OF c 5 t E 4 "+m NC rd.fim.l ;dlmrid.d ‘b a&m: Na w,m l WE/W UT: M%~qb$N 'RVf//KI : HOLE- RI :F - z ;; 5 P 2 !a = 04 O( 31 II. M see man Di - i- 6-F I?. 2-I z= y UC: z; -6 EC c & Y)- = = .OGGED BY SK/JHH AMPLED BY SR/JHH &xi& darK reddish bmw,, dry, stipt sandy clay klmar Fm: 1.9 :3.5 7.5 E LEIGHTON GEOTECHNICAL DESCRIPTION Dl’ Il’ght orr*t~ge brown, &mp,,'mdium dense, silty fine b medl'um sand; Slightly &iablc Ml-ACr - cmdinuoos, plww 84’ 11’ght olive, massive clayey silt; gypsum wd @5’ ommge imnoxlde siaining; grm fc 5’ soft, massive, n~)mercx~s small shears @is’ maroon sheared zone, I&S OC manqanese oxide &xininq, Very clayey, but 60 Confi’ndOOS khear SUrFace (ais maman bone exists as ~maII(top~~il- likc)pods) ‘ZI7.5’ firm, blocky, fmc+~+ 5)q’ less &ached sandy clayey silt a IO’ conwetion, with firm zone below c IiKe 6.41 ‘@IT’ zone of shearin "fissured clay" @ 18’ ,:~~~F,i7~~~~~~~~,“~~~~~~~~~~~d haIF way wwnd hole, +.,ms iniurafido shears 6l14.5’ shears dl’pping subparc\lle I So thm at 16’ co&d with iron oxide shining, sljckmsided 8 a’$.. n-arc shears hard So %m, blocKy, rnodcxakly ;o,.nkd ‘@23’ another zone of &wing like above but qot as iroon oxI’de stained or OS pollshed ?&224’ prominent joint bd ~P+.s seep (s-wall) on skcply inchhcdshca 8 7.5’ Firm bclaw shear a 21’ -FJ 28’ fhiq clay w/w&r b&~ sh<u Seep (N- wall) ,SSOClATES -~ - - - - - - - - - - .- - - - - - GEOTECHNICAL BORING LOG DATE 8-10.83 DRILL HOLE No, B-4 SHEET-~.--OFI PROJECT ?PO+CXX/ Vista Sanfa Fc PROJECT No. 1~~301~01-02 DRILLING CoC TYPE OF RIGbucket auger HOLE DIAMETER 30" DRIVE WEIGHT 3700# So 27.5’! 25bO#ioS5’ DROP 12 IN. F HOLES REF. OR DATUM see map WO,#S :ndr‘ii. e.f SW ..uW Ie4.z ,I N3sEj+ -.d&,, WOVb.~ 24 Ft.8 23 - s 2 2 0 L = !I :c 7. L $F 3” UC -I” & w-- GEOTECHNICAL DESCRIPTION elmor Fm: G8’ siuining llzOne of 9ypsm, yellow sulfu,: witk ~VMWOUS subhorizontal p\arw surfaces (bedd;ng?) 6,s' cemented zone below is Il'gh+ thn,damp, densc,med;um Sandj massive, SllghCly cemen-kd ‘@13’ within the sand s.sheared zone 17'* ID. eoct .zon= at 19.5' klO*r stvzwiing - - - - - - - .- - - - -. - - GEOTECHNICAL BORING LOG DATE A-IO/Ii -83 DRILL HOLE No. 5 SHEET-!-0~2 PROJECT Polvnonl \Lisb Santa Fe PROJECT No. 1~=,301~0l-02 DRILLING Co L0riVC TYPE OF RIG-~+ ntl$w HOLE DIAMETER 30" DRIVE WEIGHT 3100# So 27.5’ /260&f +0&T DROP 12 IN. ELEVATION TOP OF HOLE= REF. OR DATUM =-c map GEOTECHNICAL DESCRIPTION 22 g lL fl- 2 ii k E 5:: 5 % g; *‘;;g _I 5:: ir ZlL 2” ; I--‘: mc$ a= v+ - 2 ;: asi o Pi3 =l('Z LOGGED BY g5 I SR/JHH 63 SAMPLED BY: se X-II-I id E > -- - : TOpSOiJ: da,K brown, - -- sur+%cc), mediu -.- --- - - -I-"* L. - -.-- _ -- damp,fo m s+lcc, moist, (dry af sandy clay "';33"'+pc< part OF k&oc,K;s we&heed, 51, htiy plastic %v rnedlLw stiFf sil cloy (i;,hJ k med;tim oiive) 5)4' some gyps"" @b-l' I-l%'+h;cK sand lens thirkno tc N '@q' sandie< %' massive ' '@II-l2 , 'gy~~t%?jo~nb'ng but &II Krmtnh 813-15' nt~mwous shears wl'th random on'eotdions. shor+, d;sconfinuous ~315' still fractured, occasional shears '@lb' sandier Gl17’-18’more shears @la red cla bed; war,xd conhxmus shear z "e, J subhorizontal but-y irzegulal; shearin red clay zone 9t (mo throughovf led) tc 20: br-okn UP< "U.-W=I-OVS shears, no @20' dl'sfinct clay sewn firm sandier,*0 shears (no b&l rvptwc surfaccappsrent) QZO.5' lowest shear below +hemakl'al is rna~sivr, Y& med,bm to dchr cJ*y I? Cirmfohard, ‘1324’ cemenkd zone Czdisconfinuoekns 825’ sandier BT/ ~ncrct~'on (sandy clayey sil+) Q27.5 sandier, Massive, hard 928.5 srada-h'onal changeto sandston 5) 29' conwe.tion Qz9.5 +on, dam gAdd;l,nse, Cj;ablc,rned- - - - - - - - - - - - - - .- - - GEOTECHNICAL BORING LOG DATE R-IO/I I - 83 DRILL HOLE No, 5 SHEET-~--0~2 PROJECT 'PoIvnon/Visi-a Santa Fe PROJECT No. 1830(001-02 DRILLING Co LOvive TYPE OF RIG~~K~C auger HOLE DIAMETER 30" DRIVE WEIGHT 3700# b 27S',/Z$OOfftD55 _ DROP I2 IN. ELEVATION TOP OF HoLE~~~' REF. OR DATUM See map z u" 2-2 2 g z" 0, g GEOTECHNICAL DESCRIPTION z: 2 u EJw Lz? 55 z? ;; cc* -07 5:: 2% d=; au ; CEi g l--c& dc& -0. 2: - ;: a$ EZ -x" LOGGED BY sR/J-tlH I=, u gs w E SAMPLED BY SC=?/JHH 0 . aand I'S hard massive me.d~‘wn sand wl'+h SO~C cocwze grains : --Q' a33' mud ball 4*6x6" .' undistwbcd, OnbroKen sand ., >5- . . a37.5' hO>rta~hmvh'nuous ctay (WI) along confac+ between cloy andsand; blacK- dark blue-gray, mol'st -very mois+, Stiff, sil+y c1c.y; shearcd(<ncu%linp 338’ WC+ zone in dark 3'c'y clay -c _-- c : N my,,5 -z - _ 054 70.9 101.1 ? 2138.5' cc,lor change to .blue-g.-ay -- - - _ --. &~,P~4 21. 8 _- - p--C-- %Y;:& 4 wak seep A+ base OF send (+op of ~$2~) _ -: --_ - -rotcll dep+h 41' I;.S%k~CinztY~5Zom OF hole at=ndoCl~~i~ - 3. no caving 4. fhick sheared zone betMen 13-20.5 505A(11/77) LEIGHTON & ASSOCIATES - - - - - - GEOTECHNICAL BORING LOG DATE B-II-83 DRILL HOLE No. (D SHEETIOFL PROJECT PoI\iaon,/V;sta Santa Fe PROJECT No. I 8%%01-02 DRILLING Co 1 nvive TYPE OF RIG bucKe+aogw HOLE DIAMETER 30" DRIVE WEIGHT mff. -fn 27.5' !2500#.+~55' DROP 12 IN. t: g- I- :: 6-2 (Oh 2 5 ;; g; zv E. 2s GEOTECHNICAL DESCRIPTION $L 2:: zu t &z$ do: G2 Z% CLJ z:IL” $J E “k . = 4 ~ 2’ 5 PE ?‘? LOGGED BY 23 3 N S L=l ” SAMPLED BY - Tbpsoi I : medium to dark bror/n,dry, sfiq sandy clay I 10.61 17.5 1 @4.5’, sheared. broKen UD. oup~-rn 8, “I~ L -.- _L.~- hard no d,i.+ct .!- confi'oudos sh&hr; warpecl sn,ea, ~(somewhat confinuous), sII'cKc~~I~~~ 2 5/s- 113.y 14.1 r - j: dl’p IoN L’.- b L.- -.- :_ ‘. .-.- ,5 -7-2: -.- ,‘. ‘. --‘- -‘2-. ‘, N”f/t.$ -_-_ 20-+ RLb ‘My .‘. _ :=.e-‘- b: N*‘& __- _- 1, -.. . .= ‘,-, 25 --;;;e’;.eM/d+@ __-.- --z.- -.- --:.-- s--c- -; _ -..-I ;;-d*t+rm 53 12.5’ iron oxide shined join+s cmudion slow drikll‘n @IS.’ sandiw, I’ess somewhat a13.5' appm,x. spherical b"conce-h'On ~ZO’ fi’rm massive, sands&me 822’ b” medium brown, moist, Finn, sil9 clay wl’i-h yellow s~~lfur? “,$phanj, altwed gypsum, kwn;nA! 824’ whl'k& San massive hard medium So coa~c sand; somewha) Giable @28' gdh&,d ehangc +C silfv 6&d _ aso' grada+'onal than e into ~~arsw sand; more Gia % Ie -- - - - - .- - - - - - - - GEOTECHNICAL BORING LOG DATE B-11-83 DRILL HOLE No. b SHEET~OF~ PROJECT 7301\/~0n/V;sfa San& Fe PROJECT No, 183o(oOl-02 DRILLING Co- TYPE OF R~~bucKet au~)eK HOLE DIAMETER , 30" ,-4,+ DRIVE WEIGHT t700#527.5# io55' DROP 12 IN. ELEVATION TOP OF HoLEULL KEF. OR UATUM SC35 t-nap GEOTECHNICAL DESCRIPTION I I Q332.5' bn %l'able mc&'um& ~~me ~OCUXC sand massive to boibm OF hole I I Toiuldep+h 40.5' I. no wa!-w $, ;@yyi 4*,5’ 4. shallow(L3-7')sheaed zone <“<bilI,77, LEIGHTON & ASSOCIATES -~ - - .- - - - -- - -. ,- - - GEOTECHNICAL BORING LOG DATE A-12-83 DRILL HOLE No. 7 SHEET-~.,.-OF__~_ PROJECT Polvaon 1 Vl’sfa SQn+a Fe PROJECT No, 18 DRILLING Co. ~-arive TYPE OF RIG-++=- HOLE DIAMETER 30" DRIVE WEIGHT 3'OO e DROP. 12 IN. GEOTECHNICAL DESCRIPTION ~l'yht g,een sil+y sand in sampler tip olive, mocs+, hard sqr,dy pi It; mc\ssivc slow drilI<ng, massive \l-~y f;frn LEIGIiTON & ASSOCIATES -~~ .- - - .- - - .- - - - .- - - - - - -~ ..~ GEOTECHNICAL BORING LOG DATE 8-U-- A3 DRILL HOLE No. 7 SHEET~OF~ PROJECT -Poly2nn/ V~'s;fa Snn+a Fe PROJECT No. -L&?~M-o~ DRILLING Co I ~v;ve TYPE OF RIG~JJ~K~~ ""7~ HOLE DIAMETER ~30 ', DRIVE WEIGHT 37OO#h, 27.5’ /2500# b55' DROP 12 IN, ELEVATION TOP OF HoLEG REF, OR DATUM xe map GEOTECHNICAL DESCRIPTION I. gedcga’cally logged Cow 2,no wak 3. no CAVing I LlrTYrnn, P AccnrlnTLv - .- - - .- - - -_ - - - _- - - - - - GEOTECHNICAL BORING LOG DATE 8-12-93 DRILL HOLE No, 8 SHEET-!-OFT PROJECT+~/~;S+~ Santa Fe PROJECT No, 1830bOl-02 DRILLING Co. Layiue TYPE OF RIG ~UCK~+~LJ~W HOLE DIAMETER 30" DRIVE WEIGHT 37007~ h 27.5' ~z~~n# $0~5 DROP 12 IN. .I I. -.I + n n ELEVATION IOP OF HOLE- KEF. OR LIATIJM xcc map u 2 22 +- :: uH 27 GEOTECHNICAL DESCRIPTION fi- ;" r cc; y -z uo : z 0.O 2 ZY g; $ ; a= s-' ; t-c& dE pa " - 2 i: 2.G ;: a$2 !a :s - _ LOGGED BY ss SRI XjJ-l E w SAMPLED BY SC/ JHIA 1 I I > 4 d +*a I Topsoil: darK brob-fn, c4r-y. shff sonoy clay Delmw Formnh~: weathwed orange +deep red iron oxfde skaal'ped _ ~11i-y medium iv course sand; 6l3’ Ii h7 Olive moist, &FF, <iI+ @CL' sl'li~ Gne sane' -sandy silt iron o~ideskint 634' s eared Ame 2 cab not Gactv~, fi,rn 518.5' wncret,'or, COMrACT gradoiionci inkbedded silt/sand nodisfi'nct beds a 9.5' irregular scmd'iens 8 IO’ pmmi'nent joint I E3 14' less clay j hard,vwy Firm silt ~14-15' concretion of silti F;ne sand mostly very dense 8 20' clayey, reddish +int due to wca+hcrlnj silty sand tilzl irvegulaf concretion jol'nk4 &iable I '@ 24.5’ vwy dense havd driiifng cow~e iwe3ulw ZOOS at base &sand CDNmCT: y zone of ;htccvlse iron sfoining ~28.5’olive iron cq;de sfained clayey siii - 73 28-R plastic clayey zone, de-j sow, p<&r+c - darK 9xxy clayey silt; massi+ ha,d,nosf;~w~ ic - ~-~ - - - - - -. - -~ - - - - GEOTECHNICAL BORING LOG DATE 9-12-83 DRILL HOLE No. S SHEET~OF~ PROJECT %I~gon! Vl'sta PROJECT No, i830(oOI-O2 DRILLING Co I nriuc TYPE OF RIG-!JUCK~~ aup HOLE DIAMETER. 30" DRIVE WEIGHT 3700# tc Us . DROP 12 IN, : tjoLElie2:' RE il SEC MO.” I I I :t, - :: ;; 5:: 3P 22 =a = - ! DP - be z. 2's gi l-a = 2; 2, .A/ OX A-- = - GEOTECHNICAL DESCRIPTION .OGGED BY v SAMPLED By \ firm, massive, no+ joinkd, hard siltsCone - Ii J - -riotul depfh 35.4’ I. no cavlncj 2.no watw s.shallow shwxing at4' 4. shews atll' 5. well-developed shear' zone at 28-29' I I - - 505A(11/77) LEIGHTON & ASSOCIATES - .- - - - - GEOTECHNICAL BORING LOG DATE 8-9.83 DRILL HOLE No, 9 SHEET~OF-!-.- PROJECT PoIvann/ Vistoi Santa Fe PROJECT No, I~~O~OI-02 DRILLING Co Lakve TYPE OF RIG b[!cre+au2~/ HOLE DIAMETER 30" DRIVE WEIGHT -.XDO# in 27.5' /2-'5500# $055 DROP 12 IN, - *, IAO' t nap ~~ n~-~~~ --- ~^_- /r .,..,...I r,", "^_" er .-, LLEVATION IOP OF HOLE=- KEF, OR UATUM = rr’qp 1 L~‘“‘r’r’c’nL. ‘1”w. 3r 1 ‘f I I I I u&-? IL. 55; 2, GEOTECHNICAL DESCRIPTION I-= d=; gz iz LOGGED BY J-HHISR u SAMPLED BY JHH /SR -~~__ CL- AlIuul’um: CH 31.1 I I 18.7 IeSS clayey, very moist, plc.s~ficjsoff e +o sandy,slightly,~,-avclly j l;ght 4.0 darK 01, e, ,mo+led orange; Very moist ro we+ s&- t-2 tqEb1uf-l St? IT i 22.8 @6-lb’ sandier; vex moist sandy clay j lastic S Opt -ME,5 %‘ff - (m&-c Firm &at- ai! IO’) 19.6 6)~17' I;gh+olivf mottled omnge brawn - ~e;ry mais+ silty Finesand (vg~+s,e,;~i;cgAyFrOm side ok ho Ie> Q-10’ cliyey silt iu sil f-Y =‘aY WkiCL FRO?“. SIOL OF hOI.< ell’ f&4 holt FRd T&A depth 21' I I L. no CaVin 2. waSc* p A2 sea+ 0. slcght seep a+ 1’ b.heav c. w0.k r seep aC17' at 12’ ?z @,Ftcr 10 minutes oc cDmpletion 0 P dr;iltny 505AC11/77l LEIGHTON & ASSOCIATES .- - - - .- ~- -~ - -. - - -~ - - GEOTECHNICAL BORING LOG DATE a-9/10 -83 DRILL HOLE No. \n SHEET- 1 OF-!-..- PROJECT Polygon / VI’s& Santa Fe PROJECT No, -01-02 DRILLING Co. Lcirl’ve TYPE OF RIG bvcKe+ au2w HOLE DIAMETER 3 0 I’ DRIVE WEIGHT 3700# *s 27.5’/.7500# tc 55’ DROP 12 IN, ELEVATIO TOP OF I2.L 07.' 01.6 0 4.' = -~ 5.6 6.V 5.0 s !I.% ? ‘3.9 13.0 - siz GEOTECHNICAL DESCRIPTION OGGED BY AMPLED BY SR/JHH SR/JtW “Q;-4’ caII’che ZO~C> than e tc dK.brovvncnl ’ moist ,plCkSGC, Cali c% e, very ,Porou~ rna5sive h<yhIy wea+hwed @ 5’ medium -iu dar,L’,,,b &&‘ve,y moist, siiff,, WI dart: i-f wn sandy c IOY COarSe SC& gKin: reddish brown @ 7’ small Foot9 klmar J=J&?J a0' OIIVL ca1oe medI'um stiff 8 12’ small, disCc&inuous shears dIpping, 8l-L’ seep on NWli, Slow seep sandy clay S’ly Ql5.7’ seep ; ,xd OF chwcoal? (decaying+ highly weo,+hmd sandy ~14~ 8 20’ VKAW seep, slow Q 21-22’ caving belled I’ on N sl‘dc ” my cinpy I# I+’ on S side in r.mpiL ‘ip @ 23.5’ Total depth: 3\ ’ ~.geoloyicaII 11, logged tD 18.5’ s,seep at 20’ z,seep at ,, discor;h’nuous 3. ‘I ” lb’ SIICQS a+ $2’ b.cc.uins aI’-16’ \SSOClATES - - GEOTECHNICAL BORING LOG DATE 8- 10-83 DRILL HOLE No, L SHEETIOFI PROJECT Polvfu2n/\'l:si-a Santa Fe PROJECT No. -~83ob01-02 DRILLING Co. LCtPiVC TYPE OF RIG buc!+faugp/ HOLE DIAMETER 20" DRIVE WEIGHT 3700# h 27.5'/25bO# b.55' DROP 12 IN. ELEVATION TOP OF HOLE- REF, OR DATUM S ec GEOTECHNICAL DESCRIPTION r@8,0' wo<ped continuous shear '@J+(D' coniinuous cemenkd sand zone m d;vm s nd crjarsen~ -to medium I2hf 9~o.l mo..%ivc silti Fine& sand with oc~a3iona~ gravel ivfegl,lCN cla\Jey zone in GEOTECHNICAL BORING LOG DATE 8-10-83 DRILL HOLE No, II SHEET_~_OF~ PROJECT Polygons \/is-b Santa f+ PROJECT No,18wcoo1-o.z DRILLING Co. I arive TYPE OF RIG~~:~KC+ acy+- HOLE DIAMETER 30" DRIVE WEIGHT 3700#-&275' /256&+c 55' DROP 12 IN, N Top OF HoL~lq8'f REF. OR DATUM See ma&C;mmwnL flfit~. Pf 17) - = .EIG - = ON GEOTECHNICAL DESCRIPTION .OGGED BY AMPLED BY SR/J?iH sn/JHkl med sand iron oxide- around hole,truncak organic nea~-Vwfial- SQQM' other halF OF sand bed I's &,vn'on so&h h d;splaced abcu+lO" _ 1 kackJ7-e (kduc no+pRsen+ a eve or below sand bed) @ 31’ blue CJCCZ~ Silt grad-es inb,,zyJfy s;rf-d-s;~JA,t with~some My; gmdafional az~1-40.5&&,~ me.d. to cawse sand 8~s blue-gray SI lvp%l Total buth ‘/Y’ ‘. Geolac~r~~‘v ~or,ctb -to YI’ 1. N, c,AYlJ‘ 3 NJ0 \NLter v b~rcp~t~nwos. rfcc, shears e g-10' 5. shunviny 30-31’ 6. offrc.i sonJ bed C 35-36' \SSOCIATES I I I I I I I I I I I I I I I I I I ‘reject Name: ~oiyoon / VI’s+a So& Fe Logged By: SR/J-HI-! ENGINEERING PROPERTIES koject Number: 1830(001-02 Elevation: 110% TRENCH NO. 1 L c :qUipIIIent : Backhoe - SDER Location: see MQ~ Lo E -$ 54 a? GEOLOGIC s: GEOLOGIC n '; 2 :. ATTITUDES DATE: 8-9 - 83 DESCRIPTION: UNIT ;n 5 u" 0 Topsoil l%psoiI j 36.l Allcrvium: dar1; brown ‘m b&K, damp,tOw,Ef, sti&f Qal 2.5-3.5’ sandy clay; Sandier wi+h I’ncrcasing n6l dep+h, trace grovel 2.5-4.5’ 36-l 5.5-b-5’ wd-er seep a+ 8’ AGJ (not very permeable - wa+er table probably 5.5-7.b’ clo5e to y-ound SurFace) @@e-s’ AQ 8.!0.3’ fi Skibyivbesar 0 8Qs sat-+e GRAPHIC REPRESENTATION NE ,..&I SCALE: 1" = 5' SURFACE SLOPE:-horiz.TREND: N42 W f- I ‘I I I ‘reject Name: 'reject Number: 1~30601-0~ Logged By: S~!JHH Elevation: ll(o' L TRENCH NO. 2 :quipment: ?& GEDLOGIC ATTITUDES GRAPHIC REPRE! :khoe - SDFR DATE: 8-q -83 Alluvium : Location: see M~0 DESCRIPTION: GEOLOGIC UNIT Gal, - tl’ght tan, dry, loose, sitiy sand QQI, QQJ, - darl< bmwn, dry fcdamp, stiff, sandy clay (Colluvium) QQl2 +d Qa13 - dare brown ~TJ blacK, damph stiff, sandy clay; WI’& occasional pebLle:s &l’k”d,bm.) QC+ I 9~4 - SGmc a~ Qd3 wJ%~dy rrl+y 3ones and Some 9fA'Jel ; @/6' lens bF 3rW~h' c!AY ON w~5tdy Qal, end IA/ see?a-se, LOVING wa+er seep at (0’ b’JA?-ER DEPl-dS: - ‘ij)5-(9’ (&v-jr, drenching) 91lnM - I” in lx+tom a!%~ trenching) (io.8’deep) 9% P - @10.4’ C(3cw.M i ENGINEERING PROPERTII OQ 3-4’ AQ 3-4.4’ @a 7-8’ &la bet 7-q' 35 ay .z? ,“. 2 ,. Sam covin on SW wall @ 7.Q’ 9 Oh SCA1.F.: 1” =‘;I I I - iNTATlON NF wn\\ SIIRFACE SLOPFrahnri7 TRFNnt N?4W k--- I I I t I C3al. I I ,,,,1,I,,I,l,,I,.,lI:,.,s --e-----ee----y-e’ - I I I I I I I I I I I I I I I I I I ?roject h'm~: filvaon \1t'sta~n&~ Logged By: SR/J-I+H I.) 'reject Number: 183ObO1-CJz 20' 2 ENGINEERING PROPERTIES Elevation: I TRENCH NO. 3 :wiPment: Backhoe - SD~.R Location: see ma~ c E 5 3hF (" g3 a-' GEOLOGIC n . w 2: :z ..A w. (D ATTITUDES DATE: a-s-83 DESCRIP?ION: GEOLOGIC UNIT ;n s u" 0 Alluvium: Qal, - l<gh+ fan, dry, loose, silty sand Qal, 3s 3.2-4.2’ Lila Qal, - darK brown, damp, diff, sandy clay Qal2 3.2- 5’ Q+ - 2ornkd brown -to darK olive, damp, stiFfa Y clay j wi+h OCCOSIO~CI~ pebbles Qa13 .B a c&2-7.2* %Gil 4~14 - medium i-o darK brown, wet, siig, b.Z-8.1’ gravelly, sandy, silty clay c : Qal4 cavirn ac3 ,o-II’ wakr seep at 5.8’ WATER DEPTHS : ‘@ 11.0’ lolq An a 10.5’ IO2UAM r@ 9.5’ 1034AM GRAPHIC REPRESENTATION NE wail SCALE: 1" = 5’ SURFACE SLOPE:-ho<iz.TREND: N58W t- ; I . : , . , , , I 0 > 1 a : ) I I I I I / I I I I I I I I I I I I ‘reject Name: n/Visi-~ San&k Logged BY: . SR/JHH ENGINEERING PROPERTIES ‘reject Number: l83OcoOl-02 Elevation: 14&T’? TRENCH NO. 4 * e (n I: iquipment: B acKhhoe - SDER Location: se e ma0 L, 2-s .TE. ag o-0 22 GEOLOGIC GEOLOGIC n '7 2 E. ATTITUDES DATE: 8-0-83 DESCRIPTION: UNIT v, 2 y" CoIluv~um: da& brown, slyghfly damp ic dry, very stiPP ,ntoct: grad&ml tc hard, ,sil’u to Fine Sandy clay; with rootkk coi $ undula+ory and callche ClecKs CdesI’ccation crackafsur~) ~elmnr Fro: Td, - wcathcred Delmar 6-1: porous Ppvtlky”) -W mixed zone of il'gh+ brown-gray, damp% moist, 5-f iff clayey silt to siiq clo.y;with call&e speclk, c~ypsum-Cillcd fkAure~, I’KXI - ox;de sfainjng i and some OccasI’onaI chunK:s OF vn0r-e Firm Deimcw fm. -i-d, - olive sray, Qmp +c moisf, V cry StifCto hard, si\ty cla b\ocKy fracfure -W <wikh 3/4' +O 4" spacing), WI 4 some random pol;shed sheared surfaces, calI’che -i-‘iIled Fractures, some gypsum, ~‘ron oxide staining (darl; red ifon oxide staining a+ bo%moFkench 0 Bag Sample GRAPHIC REPRESENTATION W ~a\\ SCALE: 1" = 5’ SURFACE SLOPE:-ho-f TREND: N-S N+ I I I I I I / I I I I I I I ‘reject Name: ann/V!sta Santa fe .I I Logged By: SR/J-HH Yoject Number: 1830(~(~1 -02 Elevation:-163' t TRENCH NO. 5 iquipment: tickhoe - SDER Location: See mnD GEOLOGIC DATE: 8- 8-83 GEOLOGIC ATTITUDES DESCRIPTION: UNIT TQ~-~, I / CO/ I very stiW -Ia hard, ’ TopsoJ/~ rcdl ets, cd iche .sFk ;nhx t: 3ra&.tum at base) and undtilmor\ i Delmar Fm: olive 9ray , damp 40 moist, very stiFC to -GA hard silfy Cla~j massive, upper z-9” is weathered info ‘k”diam. chunk in DOrOOS 9 j : NbOW/75NE’ (ion GIide stow.9 matrix;. calichc, cprnmon QlOng &a’cfunS, iron Oxrde stollnlny present; large biockJ CeX+UPS gpctiny: N45W/45SYJ undulaivr joints pr dominantly dlpptny steeply N 1 zon,e of iron qxide stainI’n2 CCC@& Q basal soi2 zone c/4-%"iih;cK), undu lakory and dipp;ng ~20” boJ-h norkherly and southerly I I 4 I - -.- _ -- i I I I 1 ENGI, NE c m n LJI ERING PROPER GRAPHIC REPRESENTATION NE waI\ SCALE: 1" = 5' SURFACE SLOPE:-5"' TREND: hlbbOW f- I I I I I I I I 1 J- ! I -L--.i/ I I I I I I I I / I I I I I I I I I I ‘roj ect Name: Polqaon / Vjsfa Sanfa G Logged By: SQ/ JHI-\ J 'reject Number: 1~30(o01-0~ Elevation: IV8 -t ENGINEERING PROPERTIES TRENCH No. -!J2--- c :quipment: BacKho? - SD~P Location: see map i!? 8 $-F WI zc3 -b-. o-3 GEOLOGIC s '$ n 'k&- 2 E. ATTITUDES DATE: 0-0-83 GEOLOGIC DESCRIPTION: UNIT iA z y" Colluvium : darl: brovYn,dvy, stifc t0 very siiff, Ccl/ to fl’ne sandy clay wl+h rootlefs ontacf : Tops0 i I gmda+l’onai 4 call’che Clecks UtdUid-O~y Delmar Frn: m, codact with Td2 is scrncwhat gmdaticnal in places; in other places fhere is a ‘14” +hicK rcddtsh brown Clayey si It 547iCCJCf alOng COrrtaCt dry tu damp,dense Td, to medium sand; some iron oxide Sw,dst nc GRAPHIC REPRESENTATION NE ,,x,all SCALE: 1" =5' SURFACE SLOPE: -4”’ TREND: N5qW - I I I I I I I I I I I I I .I I I Proj cct Name : ?nlqaon / Vl’s+a SQ&. k Logged By: SR / JH H IJ 2 Project Humber: 1830(001-02 ENGINEERING PROPERTIES Elevation:_158’-f TRENCH NO. 7 Equipment: Backhoe c - SDEl? Location: see mar> 2 03 6-F hW. 0, (" z-3 s '$ 9 :. GEOLOGIC . c1 GEOLOGIC ? DATE: 8- 8-83 n, ATTITUDES DESCRIPTION: UNIT 5 < i" 0 Topsoil: darK brown, dry s+i-?fto ger sh’ff silty -tofine Topsoil sandy clay j wi+h caliche f let x s and rout4etsj darK 9m.y to black con+-inuous I l/r” thick bed O$ manganese oxi’de stained sandy SI I+ (with some :onkxt: xmcrrh& yellow sulfu~ous (?I deposits a+ NE end) along grdmnal b~secri-;contact Delmar Fm: Td, or Qld an!Qc+: 9&~Orcl ld, - sheared, mot&~, reddish brown with darl:olkcpy Td, clayey sil+ b s~l+y clayi some disconfinuous clay S*inge”, SOme gypsum (to I”+hicC siringers) and iron oxide stainin shallow dipping shearsandk&l;W 11‘ghf yay I dry So amp, Fine +o medium sand; d9j upper 6” -% is weathered So Q reddish C&or (by iron oxide staining), massive GR4PHIC REPRESENTATION NE WQ\\ SCALE: 1" = 5’ SURFACE SLOPE:-5"' TREND: N(D4W -+- I ! I I I I / 1 I I I I I I I I Project Name: Logged BY: a ?roject Number: IF)~o(~o~-o~ Elevation: 193’ -t ENGINEERING PROPERTIES TRENCH NO. 8 :qUipment : Backhoe _ SDEQ Location: .qefe maD c r 8 c" 23 .--x-. g; 0-2 GEOLOGIC I s '2 2 2. DATE: s-a-83' DESCRIPTION: GEOLOGIC " 13 ATTITUDES UNIT ? z u" l%psoil: darK brown, dry, Stiff s-!-i Topsoi I / Fine sandy clay; with CkCKS 0 I a+’ Eelmar F+n: Td, @ab’ z&%:i,‘:‘esr2:,, N-S +n N15E/q-zovJ Td, 0 3 88’ miuc+: irregular o.&gmdahoncil Td, -dark olive gmy, moist, fl.vm sil+-y clay; blocky , clayey silt+3 not highly f?&-wed, nosheas l-d 3 m0.SS ive GRAPHIC REPRESENTATION N wall SCALE: 1" =5' SURFACE SLOPE: 2" z TREND: N78w t r ; p . p E : ; : - ,4 b 1. : i = c > ; c > > . . , :- I I I I I , I I I I I 'reject ~.me: Polvoon \/I'.& Sa,-,fa F= Logged By: ,\l SR/JNH ENGINEERING PROPERTIES 'reject Number: JR~~Q,o~-~T Elevation: 179' -t TRENCH NO. 9 c :qUipment: BQcl;hoe - SDLP Location: see map ;n F ,z 5-t: 5; GEOLOGIC n ';; s:: 2 E. GEOLOGIC ATTITUDES DATE: 8-8-83 DESCRIPTION: UNIT Lx : u" Topsoil: darK brown, dry, skiff, silty sandy clay Topsoi I Pelmar Formation: @a 4’ @@b’ 3 beddkqon thin ~st~O~"dOoS day ,ed OF Tdd,: N h85E,‘15N ontack mdkm (also de ~1~’ by 2 la,K ,.&de- brown c’c4y\y”y silt) ZRAPHIC REPRESENTATION NE wall SCALE: 1" = 5' SURFACE SLOPE: 5Ot TREND: N3(oWt I I ~ I I 1 / I I / I I I , I I I ‘reject Name: n /vi.&x Santa Fk Logged BY: .SR/JH H ‘reject Number: 1~36&01 ENGINEERING PROPERTIES -02 Elevation: 212' 2 TRENCH NO. 10 ' c vl Equipment: BQcK;hoe _ SDER Location: se man 5 c?F 23 s;' ? $Z GEOLOGIC . Y ur) VW. DATE: &&& GEOLOGIC " ATTITUDES 0 DESCRIPTION: UNIT 2 u" ? Topsoi I: dQrl< brqvn, d<y, hard, ssndy clayj poco-ous,rcots l%psoi I desl’ccahon cracks to Z’, gvada-tional in& as 4’ clayey silt Delmar Fm: ;~nA.zc+:cJy=J’Y @Q Td, <5’weStc+ wca+hered, olive gceenl mol’sf,si-if~clayey Td, ~ccntact: N-m+ ~‘e~C;;;:Zj;-JgGtiT rd2 TdLa. - ,jgh+ olive &oisf sandy s&d/si I-t bed, sharp contact with Tds -4 clayey Silt; interCl'ncps with i&, ’ ’ -%a -h - ton dam TV moist Fl’ne -to medfum sand; kk&jers wit-i, Td,, and -r&, T&b tCt;hJd e OF ;roo ,,;cje c?Q;nc;j -%c - -2, mo++led +-an-or-an 317,C.QZ :rom 9”j damp -to moisf medi’um ,ypar+,+ dip”: Sand wit-h sil lens and basal (n&se N-S to NAOrr/ orange ~‘ron oxide starned zone in sand a-14-d Td, - OlfVe, ‘Jefy t%Ol’St, C\O.Yey SiIfj h1’ghly fKs.c&red, Td3 locally SOFS, c~ll’che blcbs, abundant iron orl‘d e stain in9 ) numerotis discon+inuous skxm mostly 8ub-pora/ieI,to heddin ‘Clove-on31e). k$yKe~any;y~ecnOo*;d; s&inin$?‘alsqp~Sen$ I cfa.m-3 oc ve,nsl GRAPHIC REPRESENTATIONSV\/ w~l\ SCALE: 1" = 5' SURFACE SLOPE:-4"? TREND: N24VV4 rc~&vely sharp cod-act ci’c I I I I I I I I I I I I I I I I I I I- ; I : ’ 1 -. - .I 2 : - 1 i ( c !. ?. ; 1 7 FT : _. : _ r. Project Name: V,$-a Sanfo. l=e Logged BY: SR/ J-t-l~ ENGINEERING PROPERTIES Project Number: \830(,,01-03 Elevation: 158' 2 TRENCH NO. \\ Co"m?/clrl 4LCfl ) c !quipment: Backhoe -SDFR Location: See map c 5E 17 &I K 5 23 -I. 2; O-3 GEOLOGIC DESCRIPTION: GEOLOGIC n ';; 32 *vI u v. Ln u" ATTITUDES DATE: 8-S-83 UNIT z Topsoil: darl; brown, dry, hard, many root tubules, 29 i;ogcck jr N4,w,43sfl Qelmar fm: Q&dy zone: N(oBE/l3N\11 3 N60w/bN GRhPHIC REPRESENTATION $jv\/ SCALE: 1" = 5’ SURFACE SLOPE:-@'+ TREND: ~+ddV - d++n9 <5' wcsbly N52W/1XwJ N30w/l4 SW I ‘I I 1 k 2 -! E l 5 - 5 . . t lo ENGINEERING PROPERTIES 'rojcct ?iarnc: vann VLS a SQnbFe Logged By: s,+JHH Yoject Number: iij30~01-02 iouiment : RnrlrLna - 9ncL3 T.oca+inn. CP Elevation: 158' z TRENCH NO. rcovnmcrc~(L~ nrc.41 12 \_,\I I”,. UYI~ !\ I--- _ --... ~,c- at-J\ SE 17 / 3= 02 L, % v i. 2 DATE: R-q-83 DESCRIPTION: GEOLOGI' IlNTT GEOLOGIC ATTITUDES Colluuium: darK brown, damp io dry (a+ surFace), moist! hi- depth), &ifF So hard, silty to somefincl COI syndy’ clay j w (t-h numerdus ro’otlets in upper 3 ; QaIi’Che SPECKS throughout, POrOUSj with depth (at 3’ + brown, rnol’sfl J stir becomes medium silty clay, ~omewlur+ p0~l.i with numerous &ali’&e specks,som roo+lets and at base, some jnclus;ons OF wea+hered Td clay. massive struCkh2 similar ‘to T-I I indi&+i P J 0,+0&p&" 6 Urd" '"by Delmw Fm :kiv -lined partiny, shears" l-d T - GRAPHIC REPRESENTATION w wn\\ GRAPHIC REPRESENTATION w wn\\ SCALE: 1" = 5’ SCALE: 1" = 5’ SURFACE SLOPE:-7"f TREND: SURFACE SLOPE:-7"f TREND: I I I 2 - 1 L ‘4. z -- , - -’ _- -. - -, .- - -. _*-- :- ---- -- ---. ;-d ---- 7 - - z- I I I I I I I I I I I I I I I I I I I I I I I 'reject kme: ~vaon/Vjs~&-,~Fe IJ Logged By: SR/JHH 'reject Number: 183‘&0, -02 Elevation: \&,y' 2 ENGINEERING PROPERTIES TRENCH NO. 13 iquipment: &&hoe- 9~~72 Location: see ma.0 f$mCtCla~ ARca n 1 i= m r ,z, ,^F 5-z &Z GEOLOGIC DATE: 8-q-& GEOLOGIC & ;; s: OF. ATTITUDES DESCRIPTION: UNIT ;n z u" CoIIuvI’um: dry So damp, hard sandy cla . Some plaq s+-rvcfvre w4 4 COI Sirnl lar to T-:I c$F&bnai Delmar Fm: Td, - brown, moist, atiC?, claye (weathered, somew hat p rous), J Slf- Td 1 wii-h depth; occasional fine fo and dear K <eddi%%?-k~ i?o?&?~ef’eck s-)-oh& stringers (and bn‘cl( red ~“pods), massive Td, - light brown siliy Fine sand -W YR4PHIC REPRESENTATION N wa\I SCALE: 1" = 5’ SURFACE SLOPE:40+ TREND: N4.0~ f- APPENDIX C - - - - -- - -. .- - 1830601-01 APPENDIX C LABORATORY TESTING PROCEDURES Moisture and Density Tests: Moisture content ond dry density determinations were performed on relatively undisturbed samples obtained from the test borings and/or trenches. The results of these tests are presented in the boring and/or trench logs. Where applicable, only moisture content was determined from “undisturbed” or disturbed samples. Classification Tests: Typical materials were subjected to mechanical grain-size analysis by wet sieving from U. S. Standard brass screens (ASTM D422). Hydrometer analyses were performed where appreciable quantities of fines were encountered. The data was evaluated in determining the classification of the materials. The grain-size distribution curves are presented in the test data and the Unified Soil Classification is presented in both the test dato and the boring and/or trench logs. Atterberg Limits: The Atterberg Limits were determined in accordance with ASTM D423 and AS.TM D42rfor engineering classification of the fine-grained materials. Direct Shear Tests: Direct shear tests were performed on selected remolded and/or undisturbed samples which were soaked for a minimum of 24 hours under a surcharge equal to the opplied normal force during testing. After transfer of the sample ta the shear box, and reloading the sar.lple, pore pressures set up in the sample due to the transfer were allowed ta dissipate for a period of approximately I hour prior to application of shearing force. The samples were tested under various normal loads, a different specimen being used far each normal load. The samples were sheared in a motor driven, strain-controlled, direct-shear testing apparatus at a strain rate of 0.05 inches per minute. After a travel of 0.300 inches of the direct shear machine, the motor was stopped and the sample was allowed to “relax” far approximately I5 minutes. The “relaxed” and “peak” shear values were recorded. It is anticipated that, in a majority of samples tested, the 15 minutes relaxing of the sample is sufficient to allow dissipation of pore pressures set up in the samples due to application of shearing force. The relaxed values are therefore judged to be a good estimation of effective strength parameters. The test results were plotted on the “Direct Shear Summary”. For residual direct shear test, the samples were sheared, as described in the preceding paragraph, with the rate of shearing of 0.001 inches per minute. The upper portion of the specimen waspulled back to the original position and the shearing process was repeated until no further decrease in shear strength was observed with continued shearing (at least three times resheared). There are two methods to obtain the shear values: (a) the shearing process was repeated far each normal load applied and the shear value for each normal load was recorded. One or more than one specimen can be used in this method; (b) only one specimen was needed, and a very high normal load (approximately 9000 psf) was applied from the beginning of the shearing process. After the equilibrium state was reached (after “relaxed”), the shear value for that normal load was recorded. The normal loads were then reduced gradually without shearing the sample (the motor was stopped). The shear values were recorded for different normal loads after they were reduced and the sample was “relaxed”. Maximum Density Tests: The maximum dry density and optimum moisture content of typical materials were determined in accordance with ASTM Dl557-78 (five layers). The results of these tests are presented in the test data. C-i Expansion Index Tests: The expansion potential of selected materials was evoluated by the Expansion Index Test, U.B.C. Standard No. 27-2. Specimens are molded under a given compactive energy to approximately the optimum moisture content and approximately - 50 percent saturation or approximately 90 percent relative compaction. The prepared l-inch thick by 4-inch diameter specimens are loaded to an equivalent 144 psf surcharge and are inundated with tap water until volumetric equilibrium is reached. The resulls of these tests are presented in the test data. - Consolidation Tests: Consolidation tests were performed on selected, relatively undisturbed samples recovered from the sampler. Samples were placed in a - consolidometer and loads were applied in geometric progression. The percent consolidation for each load cycle was recorded as the ratio of the amount of vertical compression to the original l-inch height. The consolidation pressure curves are - presented in the test data. Where applicable, time-rates of consolidation were also recorded. A plot of these rates can be used to estimate time of consolidation. Soluble Sulfates: The soluble sulfate contents of selected samples were determined by the - California Materials Method No. 417. ftR’f-Valu&: The resistance “R’‘-value was determined by the California Materials Method No. 301 for base, subbase, and basement soils. Three samples were prepared and exudation pressure and “R”-value determined on each one. The graphically determined “R”-value at exudation pressure of 300 psi is reported. - Triaxial Compression Tests: Triaxial compressiion tests were performed on selected remolded and/or undisturbed samples according to ASTM 2166 (unconfined) and ASTM 2850 (confined). - f--ii ? LL G “< I. L. L.9 a- ,< -” c? < Li, z ‘A 1 0 c + + c i- I-.- c L I L i L L L LA L-- RESIDUAL DIRECT SH!!.kk TEST f?E su!.-Ts i ----- -.--.- -_ ---r--“-..~“” . _^ ‘, ~^-^ --‘---..1 ^.._ -.,.,- -,.-. _.,-; _ .,-- -..“-‘-,-‘.: --.. i-,~-i-~.~- ,. , ~._ ..~ .._ , __ 310 335 273 2ES c 270 - :wD ;j f- 2ti 3 230 m '20 3, 2)" zoi .:: 192 -~' 149 L, ITO C-r 860 :z is.2 r: ii3 ; I30 '. 120 z 110 p lC0 z $5 il 60 L? 70 ' 6.0 0 sio @ 40 0 30s 20 10 0 s .~, .~~, .~,~.~!~ ~.~. ; ,~,.i. ~..~. ~,. ..~. Eli ,..... ~... ..~l.~~.~ ,. I T : 1~ “’ .~ ~,L _-.. ..~~.~~~._.,,,,~~._~.~ ~.~..~...~ ,,.. ~... .~.i ~~_~,.-.. ...~~~.. ~2 .-~-~:., _. ~,~~, .A x.1 ,i.~~ ..,,. ~; , I I / I 1 - -.’ --~- .‘----~-~-I - I ~~~ .‘~’ in ,,~~, ~,~..__~~.~~ . . -...~~.. _~ ; .,..... --- -: pi- ,.~~~~. .- , ..~~.~. ~. : , ~.~ ~~. 1. I~ 1 i \ I ~~, ~.~~,~ L. ~, ,~~ ..~.~..~.~ 8 I I I i i ’ I. ~., ..,. j ..,.. ~.~..-~,~,;...~ . . ~.L ..___. ~,..~~_/,- __.__.__.._... ~~1 L. L t I 2 3 4 5 6 7 8 NGFJ,tiAi STiiES5, KSF Sk+ ’ amnie ,oca!lon Friction Anp,k Cohssior; Spbot Remarks CLAY - BED 0 IO 0 ii: 66 PLZ?-S PI =-+I I I I I I 1 I I I I I 1 I i / I / I 2 : c C U.S. Standord Sieves I in inches -1- U.S. Standard Sieve Numbers.? I Microns 2 l-l/Z I s/4 ID 312) 4030 20 Grain Size in Millimeters t G,O”.l I Sand coar** I Fin, cm,*, Y.di”nl I Fin. 1 Sill or Cloy I GRADATION I , I I I I I I I i I I I I I I I I I E U.S. Stondord Sieves I in inches 1 I U.S. Standard Sieve Numbers-, I Microns 5 I 0.5 0.1 0.05 0.01 0.W 0.001 Groin Size in Millimeters t Gra”., I Sand co*.*, I Fin. I COW** 1 H.di”rn I Fin.3 I Silt or Clay I GRADATION TEST RESULTS CONSOLIDATION - PRESSURE CURVE PRESSURE (Kips per Square Foot) l-l!5 IO !in C 0 I 2 2 23 s .L! fY 1 G :: z 2 i : ; 57 z F : 1 0 % ” ::l~~i:l::l:::11;~!. : ,,.j ,I..,.! ,.,~;,,. ,,,, ‘; ‘:I.::::. ,, ,‘, ~,~I~, ~.,I.,~ ,, ,. I. :.. .,.. ~,I,,, .,., I-.. ,,I, /, I .,,/, I~,,,/J I l.l~ll~~~~~)::~~/ Mi$~] ,.: ~.::I.,, I.~,/,, 1~’ j::::~:# : : / ,,, .j,. .,, .., .,,, 1 ,I,,, i ..,. I,.YjT$$fj .’ ,;:: ::::i ::,: y,;yI:r::lI,/,,, ,, .~,. ,~: ml1 :,:I,‘:. .‘:: ‘Y” :;:,, ~:: j. ,I:,;, .+ ] ~: ;;: :7:: :,;j:j ;j :!:I : : ::/:::, ~::: ,.~~ ~..I,,. ,~~I~. MY.. ,.I ,... I,... 1,. ,&,;.I j;;,;Jd ., ,.,.I,,:: .:,:I!: : : :/:::; ,,: (...::,:! ,:.:.: :j::: ~~ . ..., ,,~ j ~~,j .& l,,:.M __~._~j .._. . L . .._... - ,,I .,., I.... I,... I.+ , j ~. I.... i I.... / ..,. I.~,., ., ,,,, .,.. ., .,~ ,.. I.~,, ,’ ,1, ,,., ,)... ( C I f 2 ::s 5 .o ir4 is ;i ‘; b Iti ; a7 5 5” 0 2s : u IO LC )5 0.1 CONSOLIDATION - PRESSURE CURVE ,. ,:,. .,,. .!’ , $ :;j;:; ;/;I#/$~; ,. , ,., # ,. u.u4 /. -L. 1~ _. f 8. ,. 1 ,. ,, ,~ _ _ I. 1. . ..-. 1; 1 i-’ PRESSURE (Kips per Square Foot) 0.5 1.0 5.0 10.0 50.0 0 Indicates Sample 0 Indicates Sample At Field Molsfure After Saturation o-^I-^. Lb,. I \< -4 6 II i - r? 7 ml-._ .I_ r-q I MAXIMUM DENSITY TEST RESULTS MAXIMUM DRY DENStTY (PCF) L SOIL TYPE OR OPTIMUM LOCATION SOIL DESCRIPTION MOISTURE (%I 1 By Sheperdson Engineering Associates, Inc, April 21, 1981 _ , Yellow-Brown, Clayey Silty Sand 13.0 Olive-Gray Clay 18.5 Buff Silty Sand 12.7 B-8 @ 13' Buff to Orange Sand 11.9 J. B-9 @ 15' Tan to Yellow-Tan Sand 13.7 1 B-10 @ 17' Light Tan Sand 11.1 B-11 @ 10' Light Yellow-Tan Silty Sand 14.4 1 B-13 @ 9' Light Gray-Green, Silty Clayey Sand 14.8 1 By Sheperdson Engineering Associates, Inc., June 8, 1983 B-21 @ 6'9' Dark Olive-Brown Fine Sandy Clay 12.2 1 B-33 @ 8'-10' Light Yellowish-Brown Silty Medium Sand 10.0 Olive Green Silty Clay 16.9 Brown fine Sandy Clay 13.0 _) T-33 @ 7'-8~' Yellow Tan Fine Sand 14.0 1 T-36 @ lo'-11' Dark Blue-Gray Silty Cl~ay 16.5 By Benton Engineering, November 11, 1975 Fine to Medium Sand 12.2 Clayey Fine Sand 14.8 Fine Sand 14.6 116.0 110.0 120.3 122.0 120.0 122.9 120.5 115.0 123.2 125.0 13.0 20.0 14.5 13.2 119.6 112.9 112.1 . . . . 1.~ . . 1030601-02 SUMMARY OF EXPANSION TEST RESULTS - .- - -- - - .- - - _- - - - - By Shepardson Engineering Associates, Inc., April 21, 1981. Sample Normal Stress Initial Density Moisture Content Expansion Location Condition (psf) ,_ (PSf) Initial Final (%) B-2 @ 7-8' Remolded 166 107.5 1.0% 19.4% 4.0 B-6 @ 5' Remolded 166 109.1 3.1% 18.3% 3.1 B-10 @ 17' Remolded 166 112.1 2.1% 14.7% 1.0 By Shepardson Engineering Associates, Inc., June 8, 1983 B-33@ 8-10' Air-Dried, Remolded @ 90% 150 113.4 T-31@ 12 - .Air-Dried, 2%' Remolded @ 90% 150 108.7 'T-36 @ Air-Dried, lo'-11' Remolded @ 90% 150 102.2 T-37 @ Air-Dried, lo'-12' Remolded @ 90% 150 113.1 By Benton Engineering, February 28, 1975 B-l @ 2' Natural 500 Field Moisture - B-l @ 4' Natural 144 Air Dry B-5 @ 4' Natural 500 Air Dry B-8 @ 2' Natural 500 Air Dry By Benton Engineering, November 11, 1975 B-2 @ Remolded 500 3-4' @ 92% B-2 @ 10' Natural 500 B-2 @ 15' Natural B-4 @ 10' Natural B-5 @ Remolded 7'-8' @ 92% 2.8% 14.5% 0.6 4.7% 25.7% 13.7 8.2% 30.0% 12.2 4.8% 23.8% 17.4 Air Dry 0.5 Air Dry 13.7 Air Dry 6.9 Air Dry 13.0 Air Dry 6.7 6.3 E 2:8 -~ - - - - - - - - -~ - - - - - - - .- - 1830601-02 Sample Location 8-2 @ 4'* B-3 @ 12'* B-13 @ 5'* B-17 @ ll.O'** B-18 @ 14.0'** B-21 @ 4.0'** B-24 8 6.0'** B-29 @ ll.O'** B-33 @ 13'-15'** B-34 @ 28.0'** T-12 @ 6.5'-7.0'** T-18 @ 4'-5'** T-31 @ 1.5'-2.5'** T-33 @ 7'-8'** T-36 @ 10-11'"" B-2 @ 2'*** B-8 @ 2'*** B-2 @ lo'**** B-6 @ 301**** SUMMARY OF'DIRECT SHEAR TESTS - . Undisturbed Samples Description Q Light Olive w 31" Olive Clay 26" Clayey Silty Sand 37O Greenish-Gray Sandy Clay 18' Gray-Brown Mottled Orange & Yellow Clay 8.5" Dark Blue-Gray Clay 10" Brown to Tan Sandy Clay 17O Gray Brown Sandy Clay 16' Olive Green Silty Clay 25' (Remolded?) Green-Gray Clay w/Iron Stains 34.5" Olive to Bluish-Olive Clay 10" Dark Olive-Brown Clay 15" 8rown Fine Sandy Clay 19O Yellow Fine Sand 31" Dark Blue-Gray Silty Clay 26" Undisturbed Clay 18" Silty Fine Sand 23' Clay 20" Clay to Claystone 40" * By Shepardson Engineering Associates, Inc., April 21, 1981 ** By Shepardson Engineering Associates, Inc.,.June 8, 1983 *** By Benton Engineering, February 28, 1975 **** By Benton Engineering, November 11, 1975 c (psf) 1,000 550 780 925 600 500 ~. 650 750 200 300 400 300 225 200 150 360 400 390 840 Plate C-8 1830601-02 - SUMMARY OF DIRECT SHEAR TESTS - - - - - - - - Sample Location Description @ c (PSf) B-2 @ 7'-8'* Yellow-Brown Clayey Silty Sand Olive-Gray Clay Buff Sand Buff to Orange Sand Tan to Yellow-Tan Sand Light Yellow-Tan Silty Sand Green Gray Sandy Siltstone Clayey Silty Sand Remolded 90% Clay Silty Fine Sand 35" 250 22" 350 41° 125 4o" 250 40" 250 39" 125 31" 350 35" 225 23" 200 26" 390 B-2 @ 15'-16'" B-6 @ 5'* B-8 @ 13'" B-9 @ 15'* B-11 @ lo'* B-12 @ 8'* B-13 @ 9'* B-2 @ 26'*** B-6 @ 4’-5’**** * BY - ** By *** By **** BY -. B-Z @ 15'* B-4 @ 34'* B-9 6' 33'* B-31 @ 37'*** Remolded Samples Residual Olive-Gray Clay Olive Clay Tan Clay Greenish-Blue Gray Sheared Clay 10” 150 go 180 12O 250 7.5” Shepardson Engineering Associates, Inc., April 21, 1981 Shepardson Engineering Associates, Inc., June 8, 1983 Benton Engineering, February 28, 1975 Benton Engineering, Novelrlber 11, 1975 0 - L&A Plate C-IO I I I / I .,I, I,,,, I I i I!111 lllll I ,,,,. I ! i ,I,1 ilill I I f Ljll lllll I I Ii, I / I', 1 /I,,, / I', !,,I, I: I I i / I 1 I I I (/si Iiiti ,I I! iI, I /!!_I Ii I / / . i I ,iIt//,:,I, / I : ,, ,.8/I, /I> I I I / ~/II-..+ii:l i ,:, / I i I j ,,. /-+++ 5 , f ,,,:, 1 / i : [ ((i / i / !!I, ! /i!l I I jljl il!ii / , , / I ! 1 I I I //I,,, /, ,s ,’ 1; /; !i~ /! I I 1 ~///:I /,ili / iigI:I1ilti , 6 0.1 0.1 0.5 0.5 1.0 1.0 5 5 10 10 50 50 LOAD kips/cua.tt. VISTA SANTA FE , SHEPARCSON EA;c!N?ZFXING ASSQCIA,rES. Inc. 1 1 MTE N.1 6122182 B 16 Q 9’ Na. I ..,.._1C I L&A Plate C-l I 6 0.1 0.5 1.0 5 10 50 LOAD kipa/sq.tt. SHEPARDSON Eh‘GINEERIhG AXZC-IATES Inc. VISTA SANTA FE 0.y MBC DATE 6/24/A2 B 17 @ 7’ m No. I L&A Plate C- I2 10 9 a 7 6 F 5 8 & Q 4 Z 0 3 2 0 $ 2 5 0 +l 0 -1 -2 -3 -4 -5 0.1 0.5 1.0 5 10 50 LOAD kiw/sq. ft. cgj$pg$Q VISTA SANTA FE WEPARDSON EIKXNEERIhVj ASSOCIATES. Inc. l3Y ClRTE T19 8 1.5’ - 2.5’ CT R MBC l/l/R2 XDtKl ,,n,,< I 01 ATI7 hln ,,I. L&A Plate C- I3 / I ‘I’, :,:I! ,\ i I / i / / / ,/III I;++{ ; / , I\ I,/ /ill, I I ! ,:\I I : !\‘I!1 /: i!I I 1 I , 3 4 I I 1 I , / / I,:, ,!I,/ : : I //‘,,I I,;,, i ;‘I I I 1 I ,I,!!, 1 !! I!,/ jli’l I ./I, / ! /IL ! ,IIi i/i!ti 1 ( t t / 1, !I /, ii/ / 5 I I I, :‘I / ,I;, 1 I I>\ ! I / I aill !I//1 i , $ I t ‘I’i ill;) 1 I I / NI,I Ilill 1 I : ,.,,, I , I I I:, i I Ii, I I I iI!I Ii!G 1.1 I IjIll ;,:j ,/ I :I. //! ! 6 LOAD kips/sq.ft. I VISTA SANTA FE ASSOCIKI’ES. Inc. BY MTE B 19 @ 23' MBC O/23/8? 110175 PLATE NO. 79 L&A Plate C-14 6 LOAD SIIEPARDSQN ENGINEEFXCG AS!:icpclbTE$ Inc. B 22 @ 26’ 5 10 50 kips/sq.ft. VISTA SANTA FE JY MDC C&TIE 6/2'~/R2 110175 I I’l~hl‘l~ t4n. nc, L&A Plate C- I5 z E! -2 G a i 2 . 1 I \! ;. a. ‘,!! ! 1: I .!‘I / j/II / .,a,/ 1 -I i$ --; i ; I;/;! Iilil / .!; -1:s / I: -T I I : / : -;‘-4 i ! ! 1 !-- 1 ,,. -? , I, iI{ I -4 I / I,,, / I I : 1 / ,‘, ‘/, I I /I!!~l!~~ I / I ,! !:I: (Iii! I ! / I., I 1 i 1111 ,#I) I / !I,, I ;!,I I 1 I , i ,!I 1 I’/ ~i!ll / ! I I I )!!I (!!‘I -5. .: ;I;,./;;, j I I I!// !illi 1 I / ! I / I;] ) ;iiljIili!! I 14 I ‘i.1’1 /‘Ii: I I ,I ,I I iilli i 1 I !<!I 1: I.1 / I I SZ)N lll!i I / I I I i 1 1 j , i ; 4 * I .I,/‘,,,,,, 1 I i:‘I !jll! d I / 1 /’ /ill IIiII , I ,,:ii, Ii,!! , 1 1/c ! (I’! 1 I i 0.1 0.5 1.0 5 10 50 I / LOAD kips/sca. 0. I VISTA SANTA FE I SHEPARDSON ENGINEEXING M3SQCIATES. Inc. j T23 0 4.5’ - 5.5’ LXIlE CT R ElBC 7 7,/R? IJO. .-. 110175 1 Pl.h.rv ~0. A7 ! -~ - .I - - - -~ - - - - - - .~. LOAD kips/sq.ft. (.-C&EL% ’ VISTA SANTA FE SHEF’ARDSON EhX?INEER!NG ASSOCIATES, Inc. B30 Q 21’ SY CT & M5C CNTE l/7/02 JwNO 110175 PIATI’ N”. 88 . LRA Plate C- 16 APPENDIX D 1830601-02 - - - - .- - - .- - - - - - - - - 1.0 2.0 General Intent These specifications present general procedures.and requirements for grading ond earthwork as shown on the approved grading plans, including preparation of areas to be filled, placement of fill, installation of subdrains, and excavations. The recommendations contained in the geotechnical report are a part of the earthwork and grading specifications and shall supersede the provisions contained hereinafter in the case of conflict. Evaluations performed by the consultant during the course of grading may result in new recommendations which could supersede these specifications or the recommendations of the geotechnical report. Earthwork Observation and Testing Prior to the commencement of grading, a qualified geotechnical consultant (soils engineer and engineering geologist, and their representatives) shall be employed for the purpose of observing earthwork procedures and testing the fills for conformance with the recommendations of the geotechnical report and these specifications. It will be necessary ihat the consultant provide adequate testing and observation so that he may determine that the work was accomplished as specified. It shall be the responsibility of the contractor to assist the consultant and keep him apprised of work schedules and changes so that he may schedule his personnel accordingly. It shall be the sole responsibility of the contractor to provide adequate equipment and methods to accomplish the work in accordance with applicable grading codes or agency ordinances, these specifications and the approved grading plans. If, in the opinion of the consultant, unsatisfactory conditions, such as questionable soil, poor moisture condition, inadequate compaction, adverse weather, etc., are resulting in a quality of work less than required in these specifications, the consultant will be empowered to reject the work and recommend that construction be stopped until the conditions are rectified. Maximum dry density tests used to determine the degree of compaction will be performed in accordance with the American Society for Testing and Materials test method ASTM Dl557-78. 3.0 Preparation of Areas to be Filled APPENDIX D GENERAL EARTHWORI< AND GRADING SPECIFICATIONS 3.1 3.2 Clearing and Grubbinqr All brush, vegetation and debris shall be removed or piled and otherwise disposed of. Processing: The existing ground which is determined to be satisfactory for support of fill shall be scarified to a minimum depth of 6 inches. Existing ground which is not satisfactory shalt be overexcavated as specified in the following section. Scarification shalt continue until the soils are broken down and free of large clay lumps or clods and until the working surface is reasonably uniform and free of uneven features which would inhibit uniform compaction. D-i - - - - - - - - - .~ - - .- - - - - - 3.3 3.4 3.5 3.6 3.7 Overexcavaiion: Soft, dry, spongy, highly fractured or otherwise unsuitable -.- ground, extending to such a depth that surface processing cannot adcqua,tcly improve the condition, shall be overcxcavoted down to firm ground, approved by the.consultant. Moisture Conditioning: Overexcavated and processed soils shall be watered, dried-back, blended, and/or mixed, as required to attain a uniform moisture content near optimum. Rccompaction: Overexcavated and processed soils which have been properly mixed and moisture-conditioned shall be recompacted to a minimum relaf~ive compaction of 90 percent. P Where fills are to be placed on ground with slopes steeper than 5:l horlzontal to vertical units), the ground shall be stepped or benched. The lowest bench shall be a minimum of I5 feet wide, shall Ibe at least 2 feet deep, shall expose firm material, and shall be approved by the consultant. Other benches shall be excavated in firm material for a minimum width of 4 feet. Ground sloping flatter than 5:1 shall be benched or otherwise overexcavated when consid-red necessary by the consultant. &roval: All areas to receive fill, including processed areas, removal areas and toe-of-fill benches shall be approved by the consultant prior to fill placement. 4.0 Fili Material 4. I 4.2 4.3 General: Material to be placed as fill shall be free of organic matter and other deleterious substances, and shall be approved by the consultant. Soils of poor gradation, expansion, or strength characteristics shall be placed in areas designated by ihe consultant or shall be mixed with other soils to serve as satisfactory fill material. Oversize: Oversize material defined as rock, or other irreducible material withaaximum dimension greater than I2 inches, shall not be buried or placed in fills, unless the location, materials, and disposal methods are specifically approved by the consultant. Oversize disposal operations shall be such that nesting of oversize material does not occur, and such that the oversize material is completely surrounded by compacted or densified fill. Oversize material shall not be placed within IO feet vertically of finish grade or within the range of future utilities or underground construction, unless specifically approved by ihe consultant. Import: If importing of fiII material is required for grading, the import material shall meet the requirements of Section 4. I. 5.0 Fill Placement and Compaction 5.1 Fill Lifts: Approved fiII moterial shall be placed in areas prepared to receive fill in near-horizontal layers not exceeding 6 inches in compacted thicl:nc>ss. The consultant may approve thickc,r lifts if testing indicates fhc ~l~~l~litl(l procedures ore such that a&quote cornpoction is being ochicvcd with Iii!-: of greater thickness. Each loycr shall Ibc sprcud evenly and s/la11 be thoroi~i:illy mixcd during spreading lo ai~tain unilortnity of mafcrial UKI moisture in CYK:!~ layer. - - - ,- - - - - - - - - - - - - 5.2 5.3 5.4 5.5 Fill Moisture: Fill layers at a moisture content less than optimum shot1 be watered and mixed, and wet fill layers shall be aerated by scarification or shall be blended with drier material. Moisture-conditioning and mixing of fill layers shall continue until the fill material is at a uniform moisture content at or near opi imum, Compaction of Fill: After each layer has been evenly spread, moisture- conditioned, and mixed, it shall be uniformly compacted to not less thon 90 percent of maximum dry density. Compaction equipment shall be adequately sized and shall be either specifically designed for soil compaction or of proven reliability, to efficiently achieve the specified degree of compaction. -.. Fill Slopes: Compacting of slop;es shall be accomplished, in addition to normal compacting procedures, by backrolling of slopes with sheepsfoot rollers at frequent increments of 2 to 3 feet in fill elevation gain, or by other methods producing satisfactory results. At the completion of grading, the relative compaction of the slope out to the slope face shall be at least 90 percent. Compaction Testing: Field tests to check the fill moisture and degree’ of compaction will be performed by the consultant. The location and frequency of tests shall be at the consultant’s discretion. In general, the tests will Ibe taken at an interval not exceeding 2 feet in vertical rise and/or 1,000 cubic yards of embankment. 6.0 Subdrain lnstollotion Subdrain systems, if required, shall be installed in approved ground to conform to the approximate alignment and details shown on the plans or herein. The subdrain location or materials shall not be changed or modified without the approval of the consultant. The consultant, however, may recommend and upon approval, direct changes in subdrain line, grade or material. All subdrains should be surveyed for line and grade after installation and sufficient time shall be allowed for the surveys, prior to commencement of filling over the subdrains. 7.0 Excavation Excavations and cut slopes will be examined during grading. If directed by the consultant, further excavation or overexcavation and refilling of cut areas shall be performed, and/or remedial grading of cut slopes shall be performed. Where fill- over-cut slopes are to be graded, unless otherwise approved, the cut portion of the slope shall be made and approved by the consultant prior to placement of materials for construction of the fill portion of the slope. D - iii ROCK DISPOSAL DETAIL _- - - - - - - - .- - SLOPE FACE FINISH GRADE I...- --.---- .------- -----._--,.-._ ------------__--- . --------z-.-----2zY-1--7- - - -I--r-~~-~rTT--x~ ;” ----------.-.-A------- ---. ----__--- --x.T--~~-----~ --:----zzTx-- -0 ---~-----~-,z=x-x- -ffJf-z.~~--~- - -f-p --------. --------- ---~~----~~----- .--------T-Yxz:- -- --_------- ~~---~~~-~-~--.~~-------~---~~---~---~- ------. ~===-~~~----=--==-----=--===- - - ~~~==~--=-OVERSIZE;.---- GRANULAR SOIL‘ To fill voids, densified by flooding PROFILE ALONG WINDROW ----- ---- _-----P--Y- _------ ------ D - iv BENCHING UETijlLS - - .- FILL SLOPE -_--. ----- ~ ------ __----------------~~- ___L;L’CO~~PACTED :----x:-x --~------‘c,, ( .-~ ---.-.-- .- - - - - - -~ -. - ’ REMOVE UNSU ITAB L r .e NATURAL MATERIA L ------7-- I-r(“JizL I izu I-‘LHI”lI I to I mqximum from toe 2’ MiN. 15’ MIN. KEY OWEST BENCH DEPTH (KEY) TED ------Y-Y FILL OVER CUT SLOPE REMOVE. UNSUITABLE NATURAL To be constructed prior to fill placement NOTES: LOWEST BENCH: Depth and width subject to field change based on consultant’s inspection. SUBDRAINAGE: t?ack drains may be required at the discret ion of the gcotcchnical consultant. - - - -~ -. .- - - - - - - - SIDE HILL CUT PAD DETAIL // NATURAL GROUND+/ .) 0’ /( 0 0’ 0 0 0 0 0 0 0 0 ^..__ - .._.... -- 0 0 FINISHED CUT PAD UVtHEXCAVAlt OVERBURDEN ,,,. ,- OR UNSUITABLE MATERIAL Pad overexcavation and recompoction shall be performed if determined to be necessary by the geotechnical consultant. #-- UNWEATHERED BEDROCK OR 1’ MATERIAL APPRfJVED EY THE GEOTECHNICAL CONSULTANT SUBDRAIN AND KEY WIDTH REQUIREMENTS DETERMINED BASED ON EXPOSED SUBSURFACE CONDITIONS AND THICKNESS OF OVER5URDEN - - D - vi .- - TRANSITION LOT DETAILS - - - - - CUT-FILL LOT MATERIAL APPROVED BY THE GEOTECHNICAL CONSULTANT JUT LOT NATURAL GROUND .- 41 C+ 4-c - -- /-- c- _/H.R ------------------ 7 &w’ -‘COMPACTED :-----yz-5-x ‘p q /n\v-r\\ -I- _-. T.-~~l-~~~~ ///\\\ OVEREXCAVATE AND RECOMPACT UNWEATHERED BEDROCK OR J MATERIAL APPROVED BY THE GEOTECHNICAL CONSULTANT - NOTE: Doper overescawtion and recompoction ~I1011 be performed if determined to be necessary by the gcotcchnical consultant. r-l - “ii CANYON SUBDRAIN DETAIL - - .- - - .- - NATURAL GROUND -_-_______-_--___--_--- MATERIAL Perforated Pipe Surrounded With ALTERNATE A: Filter Material FILTER MATERIAL: Filter material shall be Class 2 Ipermeol Der Slate of co 2Ic rnaieriol lifornio itondord Speciiications, or approved alternate. Class 2 grading OS follow: i. - .* . k~, .O.‘l AJ!orna!e A-l \ ‘PERFCIRATED PIPE’ 6" fi MIN. BEDDING SIEVE SIZE PEKENT PASSIX - 100 90-100 40-100 25-40 No. a 18-33 Mr. -in S-15 o-7 ..Y. “Y No.50 No.200 o-3 / 1 l/2” Gravel Wrapped ALTERNATE B: in Filter Fabric 761, ;;,,N, ,,,&,r A.‘, NOTE: I ““CrLHi- -4 In addition to the wrapped --It--- grovel, outlet portion of the subdrain should be equipped with a minimum of IO feet long perforated pipe con- nected to a nonperforated pipe MIRAFI 140 FILTER FABRIC OR -/ APPROVEr’ Alternate B-l EQUlVALEI\ I !‘2” MIN. GRAV -- -.. APPROVED EQUIVALENT d IT FI n!2 having a minimum of 5 feet in length inside the wrapped gravel. ernate B-2 \ 9 ft. I/ft. l SJDDRAIN INSTALLATION - Subdrain pipe shall be installed with perforations down or, at locations designated by the geotechnical consultant, shall be nonperforated pipe. o SUBDRAIN TYPE - Subdrclin type shall be ASTM C508 Asbestos Cement Pipe (A(?) or ASTM D275 I, SDR 23.5 or ASTM DI 527. Schcdulc 40 Acrylonitrilc Butatlicrlc~ St.:rL‘nc (ABS) or ASTM D3034 SDR 23.5 or ASTM 01785, Schedule 40 Polyvinyl Chlori&, Plustic (PVC) pipe or approved equivalent. n ..::: - - KEY l’f- DEPTH I .- 1 - .- .-. .- .- - - - - - - - SLOPE BUTTRESS OR REPLACEMENT FILL DETA -OUTLET PIPES 4" 0 Nonoerfornted Pine 30’ Max. O.C. Vertically 2’ tiIN. +-- KEY..WlOTH-+ EOUPMENT SIZE - GENERALLY I.5 FtET DETAIL A-A’ NOTES : . Fill blanket, back cut, key width and key depth are subject to field change, per report/plans. . Key heel subdrain, blanket drain, or vertical drain may be required at the discretion of the geotechnical consultant. . SUSDRAIN INSTALLATION - Subdrain pipe shall be installed with perforations down or, at locations designated by the geotechnical consultant, shall be nonperforated pipe. . SUBDRAIN TYPE - Subdrain type shall be ASTM C508 Asbestos Cement Pipe (ACP) or ASTM D275 I, SDR 23.5 or ASTM Dl527. Schedule 40 Acrylonitrile Butadiene Styrene CABS) or ASTM 03034 SDR 23.5 or ASTM D1785, Schedule 40 Polyvinyl Chlnrirle Plnctir (PVC-1 nine or nnnrnved _ ALTERNATE A ‘POSITIVE SEAL GRAVEL DR FABRIC DR APPROVED ALTERNATE B FILTER MATERIAL: Fitter material shall be Class 2 permeable material per State of California Standard Specifications, or approved alternate. Class 2 grading as follows: SIEVE SIZE PERCENT PASSIIX I 3,;" 100 90-100 318" 40- 100 No. 4 25-40 No. 8 18-33 No. 30 5-15 No. 50 o-7 No. 200 o-3 I I I I I I 1830601-02 I I I I t I I I I I APPENDIX E TABLE OF MAJOR CUT SLOPES AND FILL-OVER-CUT (TRANSITION) SLOPES Slope Reference Number PHASE A 1 2 3 Location Between Lots 123 124 and 81-82. Lots 125-129, Northwest ll-13'? (2:l) Possible landslide material 131, 132. facing Fill-over-cut (Landslide Reference 1). Lots 83-92 and compound slope transitioning between Lots 18 and 83. (Generally slopes 10'~ or more in height) i Height in Slope Feet and Aspect Slope Angle Geologic Conditions West facing lo'? (2:l) De1 Mar Formation; locally Fill-over-cut sheared. Southerly facing ll-29'* (2:l) De1 Mar Formation; locally Variable slope sheared; nearest borehole ;; ~o+.s~8,;rli~ (B-5) indicates shallow above Lots 84, bedding dipping into and out-of-slope with shearing. W-90. I I Geotechnical Conclusions and Recommendations Possibly unstable as designed. Stabiliza- tion may be required. Inspect during gradinq to assess stability. Probably unstable as designed. Buttress is recommended. Key width 20 feet; key depth 5 feet. Un- suitable landslide materials if encoun- tered during grading, should also be removed. Probably unstable as desiqned. Buttress is recommended. Key width 20 feet; key depth 5 feet. I I I I I I I I I I I I I I I \ APPENDIX E TABLE do MAJOR CUT SLOPES AND FILL-OVER-CUT (TRANSITION) SLOPES (Cont'd.) (Generally slopes 10'~ or more in height) Slope Height in Reference Slope Feet and Number Location Aspect Slope Angle Geologic Conditions 4 Lots 92 and 93 West facing B-20'+ maximum ~(edge of grading) De1 Mar Formation; locally with 20-foot sheared; nearest borehole merges with Slopes 3 and 12 at Lot 92. midslope bench. (B-5) indicates bedding neutral to slope to slightly out-of-slope. sl I 2. A. 5 6 Lot 17 West and Below Lots 10-13, 21-31'? (2:l) Upslope from possible north facing Fill-over-cut 15, 16. landslide material, in De1 Mar Formation (Landslide Reference 2). Bedding variable into and out-of-slope. Bedrock locally sheared. Below Lots l-9. Northwest 16-31l-1 (2:l) Del.Mar Formation; locally facing Fill-over-cut sheared and possible land- slide material (Landslide References 4A and 48): I I Geotechnical Conclusions and Recommendations Possibly unstable as' designed. Stabiliza- tion may be required. Inspect during grading to assess stability. Alternatively, it may be laid back to a flat- ter angle since it is a temporary slope. Probably unstable as designed. Buttress is recommended. Key width 20 feet; key depth 5 feet. Addition- al removals may be required based on in- grading'inspections. Probably unstable as designed. Buttress is recommended. Kev width ;O,;;;t; key depih . Additional removals may be required based on in-grading inspection. I I I I I I I I I I I I I 1 I I APPENDIX E TABLE OF MAJOR CUT SLOPES AND FILL-OVER-CUT (TRANSITION) SLOPES (Cont'd.) (Generally slopes lOI* or more in height) Slope Reference Number Location 7 Above Lots 25- 39. n 8 Downslope from I Lots 39 and *. 40. d. .,. 9A & 9B Upslope of Lots 71-76 (edge of grading). Slope Aspect West to. northwest facing North facing and south facing Southwest facing to southeast facing at Lot 71. Height in Feet and Slope Angle 9-34'k (2:l) Local fill- over-cut at Lots 36-39. O-17'? (2:l and variable) Some fill-over- cut. Slope transitions with Slope 7. 17-23'+ (2:l) Fill-over-cut above Lots 71- 73; 25-foot bench above Lots 73-76. Geologic Conditions De1 .Mar Formation; locally sheared. Boring B-7 and Trench T-8 indicate shallow bedding dipping neutral to out-of-slope with shearing component out-of-slope. De1 Mar Formation; 1ocall.v sheared. De1 Mar Formation; locally sheared; slope above Lots 71- 72 is upslope of landslide material (Landslide References 6 and 7). Bedding is neutral to out-of-slope (Trench T-10; Boring B-6). I I Geotechnical Conclusions and Recommendations Possibly unstable as designed. Stabiliza- tion may be required. Inspect during qrading to assess stability. Possibly unstable as designed. Stabiliza- tion may be required. Inspect during grading to assess stability. Slope above Lots 73- 76 possibly unstable as designed. Stabiliza- tion may be required. Inspect during grading to assess stability. Slope above and off- site from Lots 71- 72 probably unstable as designed. Stabiliza- tion may be required~ if adverse geologic structures are exposed. See also discussion for slope 9c. I I I I I I I I I I I I / I I I I I I APPENDIX E TABLE OF MAJOR CUT SLOPES AND FILL-OVER-CUT (TRANSITION) SLOPES (Cont'd.) Slope Reference Number Location (Generally slopes lo'? or more in height) ! Height in Slope Feet and Aspect Slope Angle Geologic Conditions Geotechnical Conclusions and Recommendations 9c Downslope from Northeast 5% (2:l) De1 Mar Formation; upslope of We recommend that Lots 68-71. facing temporary Landslide 6. Bedding is remedial grading be neutral to out-of-slope. conducted in consider- ation of future offsite improvements. Buttress is recommended for future cut slope. Key width 20 feet; key depth 5 feet. Addition- al removals may be required based on in-grading inspection. Buttress will be constructed by cutting a 20?-foot wide slot down to future planned grade, as shown on Cross-Section H-H' and Plate 1A. I I I I I I I I I I I I I I I I I APPENDIX E TABLE OF MAJOR CUT SLOPES AND FILL-OVER-CUT (TRANSITION) SLOPES (Cont'd.) (Generally slopes 10'a or more in height) I I Slope Reference Number 1G (10A and 10B) Location Slope Aspect North side of Southerly main entry road facing off of Ranch0 Santa Fe, opposite Lots 156, 39, 40, 76 at edge of tract. Height in Geotechnical Feet and Conclusions and Slope-Angle Geologic Conditions Recommendations .2-7’i (2:l) De1 Mar Formation; locally temporary sheared and landslide Although of low height, material (Landslide this slope is temporary. References 8 and 9). Tentative design indicates a major proposed (20-foot high) cut slope descending to a planned school site at the easterly portion and a flat area (no proposed slope) at the westerly portion. This grading will intersect Land- slides 8 and 9. Pro- posed grading for the current proposed slope and road should consider 'future off-site work. Buttress is recommended for future Planned cut slope (10A). Key width 20 feet; key depth 5 feet below future adjacent grade. Additional removals may be required based on in-grading inspections. Buttress will be constructed by cutting a 20+foot wide slot down to future planned grade and below for the key, as shown in Cross- Section I-I’. I I I I I I I I I 1 I I I I I I APPENDIX E TABLE OF MAJOR CUT SLOPES AND FILL-OVER-CUT (TRANSITION) SLOPES (Cont'd.) Slope Reference Number 10 (cont'd) Location m I 5 11 Lots 130, 157 and off-site (Ranch0 Santa Fe Road, portion of Retention Basin and offsite area north of "A" Street along Ranch0 Santa Fe Road). (Generally slopes 10't or more in height) Slope Aspect Height in Feet and Slope Angle Geologic Conditions Variable 8-16'T (2:l) Alluvium Fill-over-cut; proposed grading indicates fill- over-cut with cut portion O-8'+ maximum height. I / Geotechnical Conclusions and Recommendations and Plate 1A. For the ~spo4noe59dOsf,l :ta afFffoot wide key is recommended. Alternatively, this portion of the t2m- porary slope can be laid back. Probably unstable as designed. Removal of Qal will be required prior to slop2 construction. Slop2 should be totally converted to fill .slope. Minimum depth of Qal removal, 5 feet See details on Cross-Section D-D'. I I I I I I ! I I I I , I I I , I / APPENDIX E TABLE OF :IAJOR CUT SLOPES.AND FILL-OVER-CUT (TRANSITION) SLOPES (Cont'd.) (Generally slopes lOI* or more in height) / Slope Reference Number Location 12 Lots 56-59. Height Slope Feet and Aspect Slope Angle Southeast O-19'+ (2:l) Future planned fill-over-cut in area of fill slope for Phase Geologic Conditions Geotechnical Conclusions and Recommendations De1 Mar Formation; Head of Probably unstable as Landslide 3. designed. Buttress is recommended for future planned slope. A. Key width 20 feet; key depth 13+ feet below future adjacent grade. Additional removals may be required based on in-grading inspection. Buttress will be constructed by 'cutting a 20t-foot wide slot down to future planned grade and below for the key. See Cross-Section E-E'. ! I I I I I / I I I i 'I I APPENDIX E TABLE OF MAJOR CUT SLOPES AND FILL-OVER-CUT (TRANSITION) SLDPES (Cont'd.) Slope Reference Number Location COMMERCIAL AREA, SE-17 1 Below Ranch0 Santa Fe and proposed Mision Estancia. North side of proposed Mision Estancia. (Generally slopes lOI* or more in height) Height Slope Feet and Aspect Slope Angle Southerly and easterly facing Southerly facing O-17'?? (2rl?) (Tentative grading plan not clear) o-lot? (2:1?) Not shown on tentative grading plan. Geologic Conditions De1 Mar Formation; locally sheared. and possible,land- slide material (SE-17 Landslide References 2 and 3). Bedding and shearing out-of- slope to component out-of- slope. De1 Mar Formation; locally sheared and possible land- slide material (SE-17 Landslide References'2 and 3). Bedding and shearing out-of slope to component out-of- slooe. I / Geotechnical Conclusions and Recommendations Probably unstable as designed. Buttress is recommended. Key width 20 feet; key depth 5 feet. See Cross-Section SE-17 B-B'. Probably unstable as designed. Buttress is recommended. Key width 20 feet; key depth 5. feet. - - - - - - - - - - - - - - - 1830601-02 APPENDIX F TABLE OF ANTICIPATED TRANSITION LOTS Lots Shown As Transition on Grading Plans Lots with proposed shallow cuts which may result in transition lots depending on removals, benching, etc. (subject to field verification). Other lots may be determined to be transition lots durinq qrading. 1 127 2 128 i 129 131 : E ; 156 1; 23 iP :: 44 z; 58 65 111 123 124 126 F-i - - I83060 I -02 I. 2. - - - 3. APPENDIX G SLOPE STABILITY ANALYSIS Method of Stability Analysis The Modified Bishop’s Method programmed for a programmable calculator (Tl59) was utilized for slope stability analyses. One Plate G-2, the elements of the Modified Bishop’s Method are illustrated. Input and output data are defined on Plate G-3. Strengths of Materials By review of the shear strength determinations performed by our laboratory and by others, the shear strength parameters utilized for our slope stability analyses are as follows: Soil Type Angle of Internal Friction Along Bedding IO0 Compacted Fill 27’ Alluvium/Colluvium 21° Cohesion IO0 psf 250 psf ~. 200 psf ~:~; Results Plates G-l, G-3, and G-4 present results of our typical analyses performed on Cross-Section SE17 B-B’. The analyses indicate that the safety factors along the potential deep-seated failure surface, as depicted on Plate G-l, are equal or greater than the required 1.5. Other analyses (not submitted in this report) showed that safety factors for other slide areas in both SEI 7 and Phase A are greater than I .5. G-i I I I I I I I I 1: ! 1,~ i 1~ I I I I I t-3 IW - SLOPE STABIL1T-f ANALY<5I S PORTION OF CROSS. SECTION SEilBB ’ 186 166 I66 --- -- --------. \ 17.5 J yxBmwm \ 1~ - \ \ \ I+9 14s I48 149 l’r6 * /t . .. - --I- * -JJ Am. CL I&*., - . . . \ %I \? 125 -- 121 - 7- 12 D - sucx. uw4esfz -* ‘0 S.F I2 3 4 I SOIL TYPE No. - 0 22 3 I 3 I 2 3 4 S 0 2 I I I I ; ;f@ l-6 MODIFIED BlSclop ‘s t-‘llLT).~oD : SOIL ?-YfE lb. CCPSFI & KPCF) ALONG BE9 1 .I00 IO” I20 CottPtW FILL 2 250 : 27’ 120 ALLtiL’WM 3 200, 21’ 120 i8 2.q-l 272 210 165 13s 13s II0 52 J 31 2320 300 270 240 210 1g0 150 120 90 60 30 0 SL,OPE STABILITY ANALYSIS I31 SkIOr,’ MODIFIED _.- r-? E T t-l 0 .D * *I DEFfNbT,OtdS: I-- y,=SEISMlC FACTOR cz CobG SlOId f=. FRICTIOW hN6lE 2(,=lVET J)ENSlTY &p tiNIT \&iGHT OF IdA-iZR . . t an ; : row: Yw d”~orc +Q;xud -Y$ 1: +os, Ax w- )/ & (XbY,l) +(s,t-Yd.) - t .._- 2 r,= ~S~UI"IZD' FACTOR OF SAFETY (VAT(C) FL= ASSVME~ FACTOIZ OF %FET’i (SEISMIC) SF e~tcl+(~~,-u)tn!l~3/~,t !2+9J STATIC= 2 WSinc( SF -’ zip! +($$J) ++I/[ ,+ ‘~~~~~“~] SEISMIC -- .Z\tJSit7d t Z I( \rJCOSoC 1 1 ‘, I SLOPE 5TARIilTY P,NA Ly 51s CROSS- SCC‘I’iON St l-/-B&’ -.-- 0 . . 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 .<, ASSUMED SWETY FACTOR 6, ~L,CE NUI~PER .,: ~ .,~.. wJEl411T OF SLICE' (K/F) .:: 4 RESULTED SGETY FACTOR :i, ;: :;j i .:; ,... i_ !~.i j, :..:‘::iL ,~,?‘y~: ~,~ ::~:I~:.: ,s. I , ., ‘1-, i c__ ;I ;y;- i.j n xx x - I- X-COORDlNA% ../ UPPER SIDE OF SLICE . . . . . . ,:~ $OlL TYPE N UN@ER <LICE NUU6Ek i- C’ i:, t- :~J;i-~yyyYYywy >1 ..Z~ .,. / ..l( i .+.. -v- Y Y.CoOPJa\N&?E ,UPiC:\ ‘I>: . . y-2 ,i :.~ ;:- -‘:yj 1; i. OF JLICE : (;< ;;:; !“i :-f :_i i GROUND w~?TE R LIYF - i’: ‘j ,“‘, .;‘l : :~.;~ :c: ‘: ;:1 :::Ii :, 6oTior~1 tj= SLICF ~.. ;’ ; -.:y; i.:. I .‘. i:; -ibP OF SLICE i ‘/ SuCE N\lln9~IL <. 5311 7Y?E ,-JO. ((PSF) & -i’f, - ,,I /‘~Z ;.: ,.~, ..,/ :~; ~/ (,~i - <:.:‘- ALL”“ltJh\ 3 ZOO 2 I -:: L\ ;: - :-.r.-:--Ccr,‘~FCT.F,iL 2 2yo 2.;” :2‘ ~c ;Y& % i:.;. ‘.‘I- ,C! 0 yc, $53 I 100 I ;’ I;‘0 .,- ci; il c 9’ 3. 4 - RDU”%>.\‘? ,q 7; iy ri’~;T,b:, I 1 1 .l 1 1 1 1 1 1 1 1 1 1 0 ; ~..,.~^ ;~ ..~. *_. L -:? I? ....~~ 7 _, -.. L .:: .s, :-) ., / y,; !$ _ j, ?F; :y 2, if; :l~i >~ ::,:j ‘; :: ; ;-; ;:. “j y: a ..:: ./ ..::: .~. ..,,: j... i. .--. ::1 ..‘:I .I: ,.> i. ‘7 ...;L ids. ii j. :, .,>. ,: :~ :.. r: /... . . . . .’ :c: :_. : ::y: i::; 1 ,,.~. 1 ,~ :,; :,,i :; :.i, :.../ 1 ,+oject No: j?m??%2 I- (‘1 , -:^L.-- 0 *_-_-Z-L_- Plate No: (i-h- - HOMEOWNER’S GUIDELINES FOR SLOPE MAINTENANCE - -, - - - - - - - - - .- - - - - Many owners of new hillside homes do not realize that their property is in need of special maintenance. Too often, hillside homeowners become lox in proper maintenance of slope and drainage devices, resulting in catastrophic consequences. Homeowner’s Guidelines for Slope Maintenance is designed to familiorize property owners with features of their newly acquired property with which they may not be acquainted. Caverning agencies require hillside property’ developers to utilize specific methods of engineerinyand construction to protect those investing in improved lots or constructed homes. For example, the developer may be required to grade the property in such a manner that rainwater will safely leave the lot and to plant slopes so that erosion will be kept to an absolute minimum. I-le may be required to install permanent drains. However, once the lot is purchased, it is the buyer’s responsibility to maintain these safety features by observing a prudent program of lot care and maintenance. The owner who overlooks regular inspection and maintenance of drainage devices and sloping areas may expose himself +o severe financial loss. In addition to his own property damage, he may be subject to civil liability for damage occurring to neighboring properties as a result of his negligence. The following guidelines are for the protection of the buyer’s investment and are of paramount importance: I. Care should te taken that slopes, terraces, berms (ridges at crown of slopes) and proper drainage are not disturbed. Surface drainage should be conducted from the rear yard, through the sideyard, to the street. 2. Ali roof and yard runoff should be conducted to’either the street or storm drain by nonerosive devices such as sidewalks, drainage pipes, ground gutters, driveways, etc. Driveway runoff should be conducted to the street in such a manner as to inhibit small soil failures. Do not alter your drainage without first obtaining expert advice. 3. Keep all drains cleaned and unclogged, including gutters and downspouts. During he;lvy rain pe:iods, inspect drainage performance often, as this is when trouble occurs. Watch for gullying and ponding. Correct problems as soon as possible. 4. Any leakage from pools, waterlines, etc. or bypassing of drains should be promptly repaired. 5. Eliminate animal burrows and animals that make them, as they can cause diversion of surface runoff, promote accelerated erosion, and even bring about shallow soil flowage. 6. Never alter your slopes without expert advice. If your lot is built on fill, or partly on fill, consult with a soil engineer whenever you contemplate significant topographic modification of the lot. Do not spread loose fill over slopes. H-i 7. - 8. - 9. - IO. - _. I I. - - - Should you contemplate modification of manufactured or natural slopes within your property, consult with an engineering geologist. Any oversteepening may result in the need for expensive retaining devices. The undercutting of a toe-of-slope may reduce the designed safety factor which may result in slope failure. If unusual cracking, settling or earth slippage occurs, consult a qualified sail engineer or an engineering geologist immediately. Be careful with piecemeal or homemade approaches to repair of slope instability as this can result in exasperation of instability problem. Remember that most common causes of slope erosion and shallow slope failure are: a. Gross neglect in the care and maintenance of the slopes and drainage devices. b. Inadequate and/or improper planting. (Replant barren areas as soon as possible.) c. Too much irrigation or diversion of runoff over the slope. (Keep plants watered, but do not overwater.) Do not let conditions on your property create a problem for your neighbors. By working together with neighbors to prevent problems, you can not only prcmote slope stability, adequate drainage and proper maintenance, but also increase the aesthetic attractiveness of the community. - - - - - .-- H - ii