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Home My WebLink AboutCT 00-21; HOLLY SPRINGS; GEOTECHNICAL REPORTS AND LETTERS VOLUME 2; 2004-05-03•• CANTARINI PROPERTY Carlsbad, California Geotechnical Re-ports· and. Letters t, Prepared For: .. DAVID BENTLEY -41,2- ~---. _---, __ ,,wl Leighton and As soc i ates' I n C. c:-=::-.::::::-...::::::-...:::::::-_---'~ A LEIGHTON GROUP COMPANY • CANTARINI PROPERTY • • '< Carlsbad, California Geotechnical Reports an-d. Letters • Volume '2 Prepared For: _ DAVID BENTLEY ,,z ~'-------.,Leighton and As.sociatesj Inc . ......---,-------' A LEIGHTON GROUP COMPANY • • • • __ -_: ._,-, •·. __ · . : . Volume 1 1) 2) 3) 4) 5) July 28, 1998 July 8, 1999 February 3, 2000 September 15, 2000 July 9, 2001 Volume2 Date 6) November 13, 2002 7) May 3, 2004 8) 9) 10) 11) 12) 13) 14) 15) Cantarini Property Geotechnical Reports and Letters Table of Contents Preliminary Geotechnical Feasibility and Limited Subsurface Investigation Bulking and Shrinkage Estimates Preliminary Geotechnical Investigation Preliminary Geotechnical Evaluation for Tentative Map Purposes Update Geotechnical Investigation Preliminary Evaluation of Proposed Em"bankment/Detention Basin Improvements Updated Geotechnical Maps ofCantarini and Holly Springs • • • •• •• .. ••• :_;.' PRELIMINARY GEOTECHNICAL EVALUATION AND SITE RECONNAISSANCE, PROPOSED RESERVOIR EMBANKMENT/DETENTION BASIN IMPROVEMENTS, CANTARINI PROPERTY, CARLSBAD, CALIFORNIA Project No. 980160-004 November 13, 2002 . Prepared For: BENTEQ 7449 Magellan Street Carlsbad, California 92009 ----Leighton and Associ-ates, Inc. ___ .. A LE I G H TO N G RO U P COM PAN Y Leighton and Associates, Inc. A LE'IGHTON GROUP COMPANY To·: Attention: Subject: References: Introduction November 13, 2002 Benteq 7449 Magellan Street Carlsbad, Caiifornia 92009 Mr. David Bentley Project No. 980160-004 Preliminary Geotechnical Evaluation and Site Reconnaissance, Proposed Reservoir Embankment/Detention Basin Improvements, Cantarini Property, . Carls.bad, California Buccola Engineering, 2002, Tentative Tract Map for Cantarini Property, Carlsbad, California, 40-Scale, dated September 25, 2002 Leighton and Associates, Inc.; 2001 a, Geotechnical Investigation for the Proposed College Boulevard and Cannon Road, Carlsbad, California, Project No. 4990101- 002, dated March 20, 2001 · ----, 2001b, Update Geotechnical Evaluation, Cantarini Property, Carlsbad, California, Project No. 980160.a003, dated July 9, 2001 In accordance with your request and authorization, this report presents the results of our preliminary geotechnical evaluation and site reconnaissance for the proposed reservoir embankment/detention basin improvements at the Cantarirti property located northeast of the intersection of El Camino Real and College Boulevard in Carlsbad, California. The purpose of our preliminary evaluation was to observe the existing geotechnical sit~ conditions and review the previous geotechnical reports and tentative tract map -(referenced above) with respect to the proposed grading of the reservoir embankment/detention basin improvements. 3934 Murphy Canyon Road, Suite B205 • San Diego, CA92123-4425 858.292.8030·• Fax 858.292.0771 • www.leightongeo.com • •• 980160-004 Proposed Improvements Based on our review of the project tentative tract map (Buccola, 2002), we understand that the downhill ( or southwestern) side of the earth reservoir embankment on the site will be regraded in order to construct a detention basin between the reservoir embankment and the proposed street southwest of the existing reservoir. From our review of the plans, the proposed grading of the · detention basin is anticipated to cut into the existing reservoir embankment up to approximately 30 to 35 feet horizontally and up to 10 feet vertically. Findings Based on the results of our geotechnical evaluation, the following items were noted: • Site Reconnaissance • On October 29, 2002 we performed a site reconrtaissance to observe the existing geotechnical site conditions. Based on our observations, the reservoir embankment is heavily vegetated and is sustajning riparian type vegetation on the downhill side of the embankment (indicating that ground water seepage is occurring through the earth embankment). In addition, numerous animal burrows were noted and several surfidal failures are present in the upper portion of the earth embankment. Ground water migration appears to be occurring through the animal burrows during periods when the reservoir water level is elevated above the level of the burrows (and may be the cause of the surficial failures). Minor surface water was also observed flowing down the spillway on the eastern side of the reservoir embankment. Geology and Subsu"rface Conditio'ns Based on our understanding, the earth reservoir embankment consists of artificial fill soils apparently placed during the 1940's as part of the previous agricuitural activities on the property. We also understand that a report 'Yas prepru;ed by the Department of Soil Conservation but was not available for our review. The majority of the embankment fill soils are anticipated to be underlain by Quaternary-aged Alluvium and/or Colluvium while the outer edges of the embankment are anticipated to be underlain by topsoil and/or sandstones of the Tertiary-aged Santiago Formation. We ate unsure if the alluvium, colluvium, or topsoils were removed to competent formational material during the construction of the reservoir embankment in the 1940's. Based on our previous geotechnical exploration of the site (Leighton, 2001 b ), the alluvium and colluvium generally consists of loose to medium dense/stiff, silty sands, sandy days and silty clays. The actual thickness of these alluvial/colluvial soils in the general vicinity_ of the reservoir embankment is unknown, however, the thickness is anticipated to be on the order of -2-Leighton •• ••• • 980160-004 10 to 15 feet. The Santiago Formation is typically composed of dense to very dense, silty fine sandstone and to a lesser extent expansive siltstones and claystones. Ground Water Conditions From our review of the project tentative tract map (Buccola,. 2002), it is our understanding that the existing reservoir water elevation is approximately 139 feet mean sea level (msl). The reservoir water level elevation is anticipated to remain the same following completion of grading. ·around water seepage through the reservoir embankment is assumed based on the thick vegetation observed on the downstream side· of the embankment. Groun,c;l water seepage conditions and the control of ground w::,iter i's expected to be a significant factor during proposed grading of the embankment/detention basin improvements. . -. Conclusions and Recommendations · Based on the results of our evaluation including our review of previous geotechnical reports (Leighton, 200 la and 2001 b ), it is our professional opinion that the proposed development of the reservoir/detention basin improvements at the Cantarini property is feasible from a geotechnical standpoint. However, in order to confirm the subsurface geotechnical conditions (i.e. if the alluvial, colluvial, and/or topsoils are present beneath the ·existing reservoir embankment), a geotechnical subsurface investigation is recommended. The following is a summary of our conclusions and recommencl.ations with respect to the proposed development: • The earth reservoir embankment consists of artificial · fill soils apparently placed during the 1940's as part_of the previol)s agricultural activities on the property. A report was prepared by the Department of Soil Conservation but was not available for our review. • The majority of the embankment fill soils are anticipated to be underlain by Quaternary-aged Alluvium and/or Colluvium while-the oute~ edges of the embankment are anticipated to be underlain by topsoil and/or sandstones of the Tertiary-aged Santiago Formation. We are unsure if the alluvium, colluvium; or topsoils were removed to competent formational material during the construction of the reservoir embankment. • Grol,ll1d water seepage is occurring on the downhill side of the earth reservoir embankment as evidenced by the thick riparian type vegetation on the downstream side of the embankment. • The proposed grading of the detention basin is anticipated to cut into the existing reservoir embankment up to apprc;>ximately30 to 35 (eethorizontally'and up to lO'feet vertically. • lh order to minimize impacting the existing reservoir embankment, we recommend that the detention basin be redesigned to reduce the vertical and horizontal cuts into the embankment. This may be acc;omplished by: 1) moving the proposed detention basin top-of-slope closer to -3-Leighton 980160-004 the proposed street; 2) oversteepening the slope adjacent to· the street with a retaining wall or •. constru.ction of a geogrid fill slope; or 3) changing the shape of the basin. • We recommend that a geotechnical subsurface investigation be performed to evaluate the subsurface conditions of the existing embankment (including the depth, . extent, and . engineering characteristics of the existing fill soils, underlying alluvium/colluvium [if present], and groundwater elevations). Following the subsurface investigation, additional . analysis slope stability, liquefaction potential, and lateral spread analysi& should be performed. · • Since the proposed grading will significantly reduce the size of the ex1stmg reservoir embankment, at a minimum, a stability fill should be constructed along the downhill side of the reservoir embankment. The stability· fill should· have a minimum width of 10 feet with the key bottom excav·ated into competent formational material-and angled at least 2--percent into- the-slope. A subdrnin system consisting of a 47inch perforated pipe surrounded by a • ·minimum of 3 cubic feet (per linear foot) of crushed gravel wrapped in filter fabric (Mirafi 140N or equivalent) should be placed along the heel of the stability fill backcut and outletted to the slope face or storm drain system. The subdrain system may have to be placed above the heel of the key depending upon the lowest possible outlet location. Drainage panels (Miradrain G200N or equivalent) approximately 2,.feet wide placed vertically along the stability fill backcut on· 10-foot intervals should also be provided. The actual design of the stability fill should be based on the results of the recommended substirface investigation. Based on the depth and extent of the recommended stability fill, remedial grading in the bottom of the detention basin, and ground water conditions, the reservoir may need to be partially drained and/or the spillway drainage path rerouted in order to construct the recommended stability fill and perform the remedial grading operations on the down hill side . of the embankment. • · Slope Stability The proposed embankment slope was analyzed .for· deep-seated. and surficial stability (Appendix A). Preliminary slope stability analysis was performed using the PC software, -program GSTABL7. The parameters utilized in our preliminary analysis are based on our previous laboratory testirig (Leighton, 2001a and 2001b) and our experience with similar soil · types in the general vicinity of the site and are presented on Table 1. -4-Leighton ·-:· ··- 980160-004 Table 1 Preliminary Soil Strength Parameters Unit Weight Friction Angle Cohesion Material (pcf) (degrees) (psf) Artificial Fill 125 30 150 Alluvium/Colluvium 125 29 50 Santiago Formation 130 32 200 These values should be confirmed by laboratory testing of representative soil samples collected during the recommended future subsurface investigation of the existing reservoir embankment. In addition, our slope stability analysis also assumes that a suborain system (including vertical drainage panels placed on the backcut) will be installed in the recommended stability fill on the front side of the reservoir embankment to maintain the phreatic ground water surface beyond 10 feet from the_ embankment slope face. 1) Deep-Seated Slope Stability Our analysis, assuming homogeneous slope conditions arid the preliminary strength patameters presented on Table I., indicates the proposed slope embankment constructed at a 3: l (horizontal to vertical) slope inclination will have a calculated factor of safety of 1.5 or greater with respect to potential, deep rotational failure. Based on the results of our recommended future subsurface investigation, removal of the existing fill and alluviµm/colluviu:rp. to competent formational material and/or construction of a stability fill may be necessary to achieve the desired factor of safety. The proposed slopes should be constructed in accordance with the recommendations of this letter, the attached General Earthwork and -Grading Specifications fo:r Rough Grading (Appendix B), and City of Carlsbad grading requirements. 2) Surficial Slope Stability Surficial stability of the proposed 3: 1 (horizontal to vertical) or flatter embankment fill slope was evaluated (Appendix A) utilizing the strength parameters presented on Table 1. Our ·calculations indicate a factor of safety in excess of 1.5 for surficial stability under a 4- foot steady state seepage. Erosion and/or surficial failure potential of fill slopes may be reduced if the following measures are implemented during design and construction of the embankment slope. We recommend against the exclusive use of either highly expansive clayey soils or poorly graded sands. Highly expansive soils are generally known to be subject to surficial failures when exposed in slope faces. Poorly graded sands utilized in slope faces may be -5-Leighton • 980160-004 subject to excessive erosion and rilling. A mixture of clayey soils and sandy soils is recommended fo reduce the overall expansion potential and slope erosion and increase surficial slope stability. We recommend that the soil mixture be approved by the ·geotechnical consultant prior to placement of the material on the embankment slope. The embankment · slope should also be provided with appropriate surface drainage features and landscaped with drought-tolerant, slope.:stabilizing vegetation as soon as possible after grading to minimize potential for erosion. The existing reservoir spillway · should be maintained to ensure erosion of the reservoir embankment is minimized. 3) Seismic Slope Stability We analyzed: the proposed embankment for seismic slope stability utilizing ·residual strength values for the underlying alluvium/colluvium assuming an in-situ Standard ' . . Penetration Test (SPT) corrected blow count of greater than IO for the potentially liquefied layer. Our analysis also assumes that the existing fill soils within the embankment are not liquefiable and that a subdrain system and vertical drainage panels will be installed in the stability fill on the. downhill side of the reservoir embankment to maintain the phreatic ground water surface beyond 10 feet from the embankment slope face. Based on our preliminary analysis and our assumptions, a factor-of-safety of 1.1 or greater was obtained to resist deep-seated seismic slope instability. A subsurface investigation should be performed to confirm our assumptions and analysis. As previously noted, based on the results of our future subsurface investigation, removal of the existing fill and alluvium/colluvium to -competent formational material and/or construction of a stability fill may be necessary to achieve the desired ,factor of safety. Construction Observation and Plan Review The recommendations provided in this report are based on our review of· the referenced geotechnical reports and tentative tract map and professional experience with similar conditions on nearby sites. The interpolated subsurface conditions should be checked in the field during construction. Construction observation of all onsite excavations and field density testing ·of all compacted fill should be performed by a representative of thi~ office sq that construction is in accordance wi,th the .recommendations of the project geotechrtical reports. Final plans and the contract specifications should be checked by Leighton and Asso_ciates, Inc. before grading to see that the recommendations provided in the reports are incorporated into the project plans and specifications . -6-Leighton .,. "! . ••• • 980160-004 Limitations The conclusions and recommendations contained within this letter and our project geotechnical report(s) are based in part upon data that were obtained from a limited number of observations, site visits, excavc!.tions, samples, and tests. Such information is by necessity incomplete. The nature of many sites is such that differing geotechnical. or geological conditions can occur within small distances and under varying climatic conditions. Changes in subsurface conditions can and do occur over time. Therefore, the findings, conclusions, and recommendations presented in this letter and in Olll'. report can be relied upon only if Leighton has the opportunity to observe the subsurface conditions during grading and construction of the project, in order to confirm that our preliminary findings are representative for the site. · If you have any. questions regarding our letter, please contact this office. We appreciate this opportunity to be of service. Respectfully submitted, kW~ K. Wagner, CEG 1612 Dire tor of Geology Attachments: · Appendix A -Slope Stability Analysis Appendix B -General Earthwork and Grading Sp~cifications for ~ough-Grading Distribution: (2) Addressee ( 4). Ladwig Design Group Attention: Mr. Bob Ladwig -7-Leighton • A • • • • Benteq/Cantarini Property 980160-004 P:\LEIGHTON\980000-1\980160.003\ENG\CANTAR-1.PL2 Run By: Adam Terronez 11/4/2002 12:00PM 230 . . . 200· 170 140 # FS a 2.37 b 2.37 C 2.37 d 2.37 e 2.37 f 2.37 g 2.31 h 2.38 i 2.38 j 2.38 Soil Soil Total Saturated Cohesion Friction Piez. Desc. Type Unit Wt. Uriit,Wt. Intercept Angle Surface No. (pcf) (pcf) (psf) (deg) No. Fill 1 125.0 130.0 150.0 30.0 W1 Qal. 2 125.0 130.0 50.0 29.0 W1 Tsa 3 130,0 130.Q 200.0 32.0 W1 Wl 2 3 ·--~---- ~- 3 • --------·-···-·· Wl 2 3 110 ~-----~--------'--------'--------~--------'------,._] 0 30 60 90 120 150 180 GSTABL7 v.2 FSmin=2.37 ~ Safety Factors Are Calculated By The Modified Bishop Method •-·· •••• ••• P:\leighton\980000-1\980160.003\eng\cantar-l.OUT Page 1 *** GSTABL7 *** ** GSTABL7 by Garry .Ji. ·Gregory, P.E. ** ** Original Version 1.0, January 1996; Current Version 2.002, December 2001 ** (All Rights Reserved-Unauthorized Use Prohibited) *********************************~*********************************************** SLOPE STABILITY ANALYSIS SYSTEM Modified Bishop, Simplified Janbu, or GLE Method of Slices. (Includes Spencer & Morgenstern-Pr~ce Type Analysis) Including Pier/Pile,_ Reinforcement, Soil Nail, Tieback, Nonlinear Undrained Shear Strength-, Curv(;!d Phi Envelope, Anisotropic Soil, Fiber-Reinforced Soil, Boundary µoads, Water Surfaces, Pseudo-Static Ea,rth,quake., and Applied Force Options. ********************************************************************************* Analysis Run Date: 11/4/2002 · 'rime of Run: 12: OOPM Run By: .Adam Terronez Input Data Filename: P:cantar-1.txt Output Filename: P:cantar-1.0UT Unit System: English Plotted Output Filename: P:cantar-1.PLT PROBLEM DESCRIPTION: Benteq/Cantarini Property BOUNDARY COORDINATES 7 Top Boundaries 13 Total Boundaries 980160-004 Boundary X-Left No. (ft) 1 0.00 Y-Left . (ft) 144.00 144.00 127.00 128.00 140.00 138.00 131.00 124.00 127.00 126.00 114. 00 121.00 122.00 X-Right (ft) 2.00 42.00 68.00 112. 00 124.00 150.00 180.00 Y-Right (ft) 144.00 127.00 128.00 140.00 138.00 131.00 130.00 127.00 126.00 131.00 12:L.OO 122.00 124.00 Soil Type Below Bnd 1 2 2. 00 3 42. 00 4 68.00 5 112.00 6 124.00 7 150. 00. 8 0. 00 9 42. 00 10 72.00 11 0.00 12 92.00 13 150.00 user Specified Y-Origin ISOTROPIC SOIL PARAMETERS . 3 Typ13 (.s) of Soil 42.00 72.00 150.00 92.00 150.00 180.00 110.00(ft) 1 1 1 1 1 2 2 2 2 3 3 3 Soil Total Saturated Cohesion Type Unit Wt. Unit Wt. Intercept Friction Angle (deg) 30. O· 29.0 32.0 Pore Pressur!=! Piez. Pressure Constant Surface No. ()?cf) (pcf) (psf) 1 125.0 130.0 150.0 2· 125.0 130.0 50.0 3 130.0 130.0 200.0 1 PIEZOMETRIC SURFACE(S) SPECIFIED Unit Weight of Water= 62.40 (pcf) Piezometric Surfac.e No. 1 Spe_c±fied by Pore Pressure Inclination Factor 0.50 Point X-Watet Y-Water No. (ft) (ft) 1 42.00 1~7.00 2 68.00 128.00 3 84.00 128.00 4 124.00 139.00 5 180.00 139.00 Parara.. (psf) 0.00 0.0 0.00 0.0 0.00 0.0 5 Coordinate Points A Critical Failure Su~face Searching Method, Using A Random Technique For Generating C.ircular Sur·faces, Has Been Specified. 300 Trial Surfaces Have Been Generated. No. 1 1 1 20 Su-rface(s) Initiate(s) From Each Of 15 Points Equally Spaced Along The Ground Surface Between X 52.00(ft) and X 64.00(ft) Each Surface Terminates Between X 112.00(ft) •.. : •• P:\leighton\980000-1\980160.003\eng\cantar-1.0UT Page 2 and x = 125.00(ft) Unless Further Limitations Were Imposed, The Minimum Elevation At Which A Surface Extends Is Y = 120.00(ft) 2.00(ft) Line Segments Define Each Trial Failure Surface. Following Are Displayed The Ten Most Critical -Of The Trial Failure Surfaces Evaluat~d. They Are Ordered -Most Critical First. **Safety factors Are Calculated By The Modified Bishop Method Total Number of Trial Surfaces Evaluated= 300 Statistical Data On All Valid FS Values: FS Max= 4.720 FS Min= 2.365 FS Ave= 2.784 Standa·rd Devi.ation =· 0. 4 99 Coefficient of Variation Failure Surface Specified By 35 Coordinate Points Point X-Surf Y-Surf No. (ft) (ft) . 1 57.14 1~7.58 2 58.88 126.58 3 60.65 125.66 4 62.~6 124.81 5 64. 31 124. 04 6 66.18 123.35 7 68.09 122.74 8 70. 02 122.22 9 71.97 121.78 10 73.94 121.42 11 75.92 121.15 12 77.91 120.96 13 79.91 120.86 14 81.91 120.84 15 83.91 120.91 16 85. 90 121. 07 17 87.89 121.31 · 18 89. 86 12L 63 19 91.82 12~.05 20 93.75 122.54 21 95.67 123.12 22 97.56 123.78 23 99.42 124.52 24 101. 24 125 .. 34 25 103.03 126.23 26 104.78 127.20 27 106.48 128.25 28 108.14 129.37 29 109.75 130.56 30 111.30 .131.82 31 112.80 133.14 32 114.24 134.52 33 115.62 135.97 34 116.94 137.48 35 118.14 138.98 * * 17.92 % Circle Center At X = 81.28 ·y 167.38 and Radius 46.54 F~ctor of Safety *** 2.365 *** Individual data on the 41 slices Water Water Tie Tie Earthquake -Poree Force -Poree Force Force Surcharge Slice Width Weight Top Bot Norm Tan Hor Ver Load No. (ft) (lbs) (lbs) (lbs) (lbs·) (lbs) (lbs) (lbs) (lbs) 1 1. 7 120.1 0.0 66.5 0. 0. 0.0 0.0 0.0 2 0.3 44.4 0.0 24.0 0. 0. 0.0 0.0 0.0 3 1'.5 316.0 0.0 170.9 0. 0. 0.0 0.0 0.0 4 1.8 593.0 0.0 314.1 0. 0. 0.0 0.0 0.0 5 1.8 815.3 0.0 423.6 0. o. 0.0 0.0 0.0 6 1. 9 1024.6 0.0 523.5 0. 0. 0.0 0.0 0.0 7 1.8 1157. 5 o.o 582.7 0. 0. 0.0 0.0 0.0 8 0.1 61.1 0.0 30.7 0. 0. 0.0 0.0 0.0 9 1..9 1453. 8 0.0 688.7 0. o. 0.0 0.0 o .·o P: \leighton\9800.00-1 \980160. 003\eng\cantar-l .OUT Page 3 •• 10 2.0 1721.1 0.0 749.1 0. 0. 0.0 0.0 0.0 11 0.0 28.6 0.0 12.0 0. .o. 0.0 0.0 0.0 12 1. 9 1941. 4 0.0 787.0 0. 0 .. 0.0 0.0 0.0 13 2.0 2198.2 ,o. 0 838.3 0. 0. 0.0 0.0 0.0 14 2.0 2403.6 0.0 867 .1 0. 0. 0.0 0.0 0.0 15 2.0 2584.4 0.0 885.1 0. 0. 0.0 0.0 0.0 16 2.0 2739.2 0.0 892.5 0. 0. 0.0 0.0 0.0 17 2.0 2866.8 0.0 889.1 0. 0. 0. 0 · 0.0 0.0 18 0.1 137.6 0.0 41. 6 o. 0. 0.0 0.0 0.0 19 1. 9 2828.8 0.0 834.0 0. 0. 0.0 0.0 0.0 20 2.0 3.042.2 0.0 916.1 0. 0. 0.0 0.0 0.0 21 2.0 3089.1 0.0 947.4 0. 0. 0.0 0.0 0.0 22 2.0 3106.9 0.0 968.1 0. 0. 0.0 0.0 0.0 23 1. 9 3095.7 0.0 978.1 0. 0. 0.0 0.0 0.0 24 1.9 3056.3 0.0 977.3 0. 0. 0.0 0.0 0.0 25 1. 9 2989.5 0.0 965.8 0. 0. 0.0 0.0 0.0 26 1. 9 2896.4 0.0 943.6 (). 0. 0.0 0.0 0.0 27 1.8 2778.6 0.0 910.8 0. 0. 0.0 0.0 0.0 28 1.8 2637.8 0.0 867.3 0. 0. 0.0 0.0 0 .. o 29 1. 7 2475.9 0.0 813.3 0. 0. 0.0 0.0 0.0 30 1. 6 2197.7 0.0 717.7 0. 0. .0.0 0.0 0.0 31 0.1 97.6 0.0 31.3 0. 0. 0.0 0.0 0.0 32 1. 7 2098.3 0.0 674.2 0. 0. 0.0 b.O 0.0 33 1. 6 1887.6 0.0 589.3 o. 0. 0.0 0.0 0.0 34 1. 6 1666.0 0.0 494.4 0. 0. 0.0 0.0 0.0 35 0.7 691. 7 0.0 195.3 0. 0. 0.0 0.0 0.0 36 0.8 727 .3 0.0 194.4 0. 0. 0.0 . 0. 0 0.0 37 1.4 1081. 9 0.0 275.3 0. 0. 0.0 0.0 0. 0 · 38 1. 4 744.3 0.0 151.5 0. 0. 0.0 0.0 0.0 39 · 0. 8 302.2 0.0 27.7 0. 0. 0.0 o.o 0.0 40 0.5 121.3 0.0 0.0 0. 0. 0.0 0.0 0.0 ••••• • 41 1.2 127.9 0.0 0.0 0. 0. 0.0 0.0 0.0 Fa·ilure Sur+ace .Specified By 36 Coordin_ate Points Point X-Surf Y-Surf No. .(ft) (ft.) 1 57.14 127.58 2 58.88 126.59 3 60.66 125.68 4 62.47 124.84 5 64.32 124.08 6 66.20 i?3.39 7 68.11 122.79 8 70.04 122.27 9 71.99 121. 83 10 73.96 121.48 11 75.94 121 •. 21 12 77.94 121.02 13 79. 93 120.92 14 81. 93 120.90 15 83.93 120.97 16 85.93 121.12 17 87.91 121.36 18 89.89 121.68 19 91. 84 122 .·09 20 93.78 122.57 21 95.70 123.14 22 97.59 123.79 23 99.46 124.51 24. 101. 29 125.32 25 103.09· 126.21 26 104.83 127.17 27 106.55 128.20 28 108. 21 129.30 • 29 109.83 1~0.48 30 111. 40 131. 72 31 112.91 133.03 32 114. 37 134.40 P:\leighton\980000-1\980160.003\eng\cantar-1.0UT, Page 4 • 33 115. 77 135.83 34 117 .10 137.32 35 118. 37 138.86 36 118. 43 138.93 Circle Center At X = 81. 34 ; y = 168.04 and Radius 47.14 Factor of Safety *** 2. 367 *** Failure Surface Specified By 36 Coordipate Points Point x-su:is-.f Y-Surf No .. (ft) (ft) 1 54.57 127.48 2 56.30 126.48 3 58.07 125.55 4 59.88 124.70 5 61. 72 123.92 6 63.60 123.22 7 65.50 122.60 8 67.42 122.06 9 69.37 121. 60 10 71.33 121.22 11 73.31 120.92 12 15.30 120.71 13 77.30 120.59 14 79.30 12.0. 54 15 81. 30 120.58 16 83.29 120.7i 17 ~5.28 120.91 18 87.26 ·121. 21 19 89.22 121.58 2,Q 91.17 122.03 21 93.10 122.57 ••• 22 95.00 123 .. 19 23 .96. 88 123.89 24 98. 72 124.66 25 100.53 ·125.51 26 102.30 126.44 27 104.03 127.44 28 105.72 128.51 29 107.36 129.65 30 108.96 130_.86 31 110.50 132.14 32 111. 98 133.48 33 113. 41 134.88 34 114.78 136.34 35 116. 08 137.85 36 117.11 139.15 Circle Center At X = 79.34 ; y = 168.18 and Radius 47.64 Factor of Safety *** 2.368 *** Failure Surface Specified By 37 Coordinate Points Point X-Surf Y-Surf No. (ft) (ft) 1 54.57 127.48 2 56.31 126.49 3 58.08 125.57 4 59.89 124. 72 5 61. 74 123.94 6 63.61 :).23.24 7 65.51 122.61 8 67.43 122.06 9 69.38 121.59 10 71.34 121. 20 11 73.31 120.89 • 12 75.30 120.66 13 77.29 '120.51 14 79.29 120.43 15 81.29 120.44 P:\leighton\980000-1\980160.003\eng\cantar-l.OUT Page 5 •• 16 83 .. 29 120.53 17 85.28 120.70 18 87.27 120.95 19 89.24 121.28 20 91. 20 121.69 21 93.14 122.18 22 95.05 122.74 23 96.95 123.39 24 98.82 124.10 25 100.65 124·. 90 26 102.45 125.76 27 104.22 126. 70 28 105.95 127.71 29 107.63 128.79 30 109.27 129.93 31 110. 86 131.14 32 112. 41 132.42 33 113. 90 133.75 34 115. 33 135.14 35 116. 71 136.59 36 118.03 138.10 37 118. 67 138.89 Circle Center At X = 80.07 ; y = 170.03 ; and Radius 49.60 Factor of Safe.ty *** 2.371 *** Failu:i;e Surface Specified By 36 Coordinate Points Poi:n,t X-Surf Y-Surf No. (ft) (ft) 1 54.57 127.48 2 56.33 126.53 3 58.13 125.65 ••• 4 59.96 124.84 5 61.82 124 .11 6 63.70 123.45 7 65. 62 122.87 8 67.55 122.36 9 69.51 121.94 10 71. 48 121.59 11 73.46 121. 32 12 75.45. 121.13 13 77.45 121.03 14 79.45 121. 00 15· 81. 45 121.05 16 ·93 .44 121.19 17 85.43 121.40 18 87.41 121.69 19 89.37 :t.22.07 20 91.32 122.52 21 93.25 123,05 22 95.15 123.66 23 97. 03 · 124.34 24 98.88 125.10 25 100.70 125.93 26 102.49 J,26.84 27 104.23 127.81 28 105.94 128,86 29 107.60 129.97 30 109.21 :I.31. 15 31 110.78 132.39 32 112.30 133.70 33 113. 76 135.07 34 115.16 136.49 35 116. 51 137,97 • 36 117.45 139.09 Circle Center At X = 79.11 ; y 170.66 and Radius 49. 67 Factor of Safety *** 2.372 *** P:\leighton\980000-1\980160.003\eng\cantar-l.OUT Page 6 Failure Surface Specifietj By 35 Coordinat~.Points Point X-Surf Y-Surf No. (ft) (ft) 1 55.43 127.52 2 57.12 126.44 3 58.85 125.45 4 60.63 124.54 5 62.45 123.71 6 64.31 122.96 7 66.20 122.30 8 68.11 121.73 9 70.05 121.25 10 72.02 120.86 11 73.99 120.56 12 75.98 120.36 13 77.98 120.24 14 79. 98 120.22 15 81~98 120.29 16 83.97 120.45 17 85.96 120.70 18 87.93 121.05 19 89.88 121.49 20 91.81 122.01 21 93.71 122.63 22 95-58 123.33 23 97.42 124.12 24 99.22 124.99 25 100.98 125.94 26 102.69 126.98 27 104.35 128.09 28 105.96 129.28 29 107.51 130.54· 30 109.00 131.87 ·31 110.43 133.27 32 111.80 134.74 33 113.09 136.26 34 114.31 137.85 35 115.42 ll9.43 Circle Genter At X = 79.47 ; y = 163.45 and Radius 43.24 Factor of Sa~ety *** 2.373 *** Fail1,1.re Surface Specified By 33 Coordinate Points Point X-Surf Y-Surf N6. (ft) (ft) l 58.86 127.65 2 60.56 126.60 3 62.32 125 .. 64 4 64.11 124.77 5 65.96 123.98 6 67.83 123.29 7 69 .. 74 122.70 8 71. 68 122.20 9 73.64 121. 79 10 75.61 121.48 11 77.60 121.28 12 79.60 121.17 13 81. 60 121.16 14 83-. 60 121.24 15 85.59 121. 43 16 87.57 121. 72 17 89.53 122.10 18 91. 47 122.58 19 93.39 123.16 ••• 20 95.27 123.83 21 97.12 124.59 22 98.93 125.45 23 100.69 126.39 ••• •• ••• P:\leightbn\980000-1\980160.003\eng\cantar-l.OUT Page 7 24 102.41 127.42 25 104. 07 128.53 26 105.67 129.73 27 107.22 131. 00 28 108.69 132.35 29 110.10 133.77 30 111. 44 135.25 31 112. 70 136.80 32 113.89 138.42 33 114. 64 139.56 Circle Center At X = 80. 81 ; y = 161. 46 and Radius Factor of Safety . *** 2.374 *** Failure Surface Specified By 36 Coordinate Points Point X-Surf Y-Surf No. (ft) (ft) 1 53. 71 127.45 2 55.45 126.46 3 57.23 125.54 4 59.04 124.69 5 60.89 123.92 6 62. 76 123.23 7 64. 67 122.62 8 66.59 122.09 9 68.54 121.63 10 70.51 121. 26 11 72.49 120.97 12 74.48 120.77 13 76. 47 120.64 14 78.47 120.60 15 80.47 120.64 16 82.47 120.77 17 84.46 120.98 18 86.43 121.27 19 88.40 121.64 20 90 .. 35 122.10 21 ·92.27 122.63 22 94.18 123 . .25 23 96.05 123.94 24 97.90 124.71 25 99.71 125.56 26 101. 48 126. 48 27 103.22 127.48 28 104.91 128.54 29 i06.56 129.68 30 108.16 130.88 31 .109. 70 132.15 32 111.19 133.48 33 112. 63 .134. 87 34 114. 01 136. 32. 35 115. 32 137.83 36 116.46 139.26 Circle Center At X = 78.45 ; y 168. 67 and Radius Factor of Safety *** 2.375 *** Fa,ilure Point Surface Specified.By 35 Coordinate Points No. 1 2 3 4 5 6 7 8 9 X-Surf Y-Surf (ft) (ft) 55.43 127.52 57.20 126.59 59.01 125.73 60.85 124.95 62.72 124.24 64.62 123.61 66.54 123.06 68.48 122.58 70.44 122.20 40.32 48.07 P: \leighton\980000-1.\980160. 003\eng\cantar-1. OUT Page 8 .: 10 72.42 121.89 11 74.41 121.66 12 76.40 121. 51 13 78.40 121.44 14 80.40 121.46 15 82.40 121. 56 16 84.39 121.74 17 86.37 122.00 18 88.34 122.34 19 90.30 122. 7 6 20 92.23 123.27 21 94.15 123.85 22 96.03 124.51 23 97.89 125.24 24 99. 72 126.06 25 101. 51 126. 94_ 26 103.27 127.90 2.7 104.98 128.93 28 106.65 130.03 29 108.28 13·1.20 30 109.85 132.43 31 111.38 133. 73 32 112.84 135.09 33 114. 26 136.50 34 115. 61 137.98 35 116.66 139.22 C:i:rclE? Center At X = 79.01 ; y = 170.21 ; and Radius 48.77 Factor -of Safety *** 2.376 *·** Failure Surface Specified By 34 -Coor~inate Points Point X-Surf Y-Surf • :.:. No . (ft) (ft) 1 58.00 127.62 2 59.66 126.50 3 61.37 125.46 4 63.13 124.52 5 64.94 123.66 6 66.79 122.90 7 68.67 122.23 8 70.59 121. 65 9 72.53 121.1.8 10 74.50. 120.80 11 76. 48 120.53 12 78.47 120.35 13 80.47 120.28 14 82.4.7 120.30 15 84. 46 120.43 16 86. 45 120.66 17 8-8. 42 120.99 18 90.38 "121.42 19 92.31 121. 94 20 94.21. 122.57 21 96.07 123.28· 22 97.90 124.10 23 99.69 125.00 24 101.42 125.99 25 103 .11 127.07 26 104.73 128.24 27 106.30 129.48 28 107.80 130.80 29 109.23 132.20 30 110.59 133.66 31 111. 88 135. 20 • 32 113.08 136.79 33 114.20 138.45 34 114.86 139.52 Circle Center At X == 80.94 ; y = 159.78 ; and Radius 39.51 • ••• .. • P:\leighton\98000d-1\980160.003\eng\cantar-1.0UT Page 9 Factor of Safety *** 2.377 *** **** END OF GSTABL7-OUTPUT **** • • • Benteq/Cantarini Property ,980160-004 (Seismic) P:\LEIGHTON\980000-1\980160.003\ENG\CANTAR-2.PL2 Run By: Adam Terronez 11/4/2002 12:08PM 230 _ 200 170 140 # FS· a 1.13 b 1.13 C 1.14 d 1.14 e 1.14 f 1.14 g 1.14 h 1.14 1.14 1.15 Soil Soil Total Saturated Cohesion Friction ·Piez. Desc, Type Unit Wt. Unit Wt. Intercept Angle Surface No. (pcf) (pcf) (psf) (deg) No. Fill 1 125.0 130.0 150.0 30.0 W1 Qal 2. 125.Q 130.0 200.0 0.0 0 Tsa 3 130.0 130.0 200.0 32.0 W1 a _\t~h j j ~ . ~~··1~7~;:_:_··-· ____ .. _,. ___ -··----.. -.. _ .. ____ ,.Wl -------------~-~ .. -··· / /,, 1...._____ 2 :i f¥!®%-JL-:: ... · ... _._ .... _ .. _ .. --l,ff ___ .. --~~ -===------=-----1 ----~...,, .... ·-" 2 1 3 l 3 ~"" ' e-~-3 ·-O 110 L ____ ---1. _____ _..1__:__ ___ ~L_----~:--------::~---- o 30 60 90 120 150 180 GSTABL7 v.2 FSmin=1.13 ~ Safety Factors Are Calculated By The Modified Bishop Method •-- • • P:\leighton\980000-1\980160.003\eng\cantar-2 .. 0UT Page 1 *** GSTABL7 *** ** GSTABL7 by Garry H. Gregory, P.E. ** ** _Original Version 1.0, January 1996; Current Version 2.002, December 2001 ** (All Rights Reserved-Unauthorized Use Prohibited) * * * * * * * * * * * * * * * * * * * * * *"*** * * ** ** * * * *** * * ** * * * ** * * * ** * * * *'* * * * * * * * * * * * * * * * * * * * * * * * ** SLOPE STABILITY ANALYSIS SYSTEM Modified Bl.Shop, Simplified Janbu, or GLE Method of Slices. (Includes Spencer & Morgenstern-Price. Type.Analysis) Including Pier/Pile, Reinforcement, Soil Nail, Tieback, Nonlinear Undrained Shear Strength, Cu-rved Phi Envelope, Anisotropic Soil, Fiber-Reinforced Soil, Boundary Loads, Water Surfaces, Pseudo-Static Earthquake, and Applied Force Options. *********~*********************************************************************** Analysis Run Date: 11/4/2002 Time of Run: 12:08PM Run By: Adam Terronez Input Data Filename: P:cantar-2.txt Output Filename: P:cantar-2.0UT Unit System: English Plotted Output Filename: P:cantar-2.PLT PROBLEM DESCRIPTION: Benteq/C?ntarini Property BOUNDARY COORDINATES 7 T-op Boundar:i,.es 13 Total Boundaries 980160-004 (Seismic) Boundary X-Left No. (ft) 1 0. 00 Y-Left (ft) 144.00 144. 00 127.00 128.00 140.00 138.00 131.00 124.bO 127.00 126.00 114.00 121.00 122.00 X-Right (ft) 2.00 42.00 68.00 112.00 124.00 150.00 180.00 Y-Right (ft) 144.00 127.00 128.00 1.40. 00 138.00 131.00 130.00 127.00 126.00 131.00 121. 00 122.00 124.00 Soil Type Below Bnd 1 2 2. 00 3 42. 00 4 68. 00 . 5 112.00 6 124.00 7 150.00 8 o:·oo 9 42. 00 10. 7-2.00 11 0. 00 12 92.00 13 150.00 User Specified Y-Origin ISOTROPIC SOIL PARAMETERS 3 Type(s) of Soil 42.00 72.00 150.00 92.00 150.00 180.00 110.00(ft) 1 1 1 1 1 2 2 2 2 3 3 3 Soil Total Saturated Cohesion Type Unit Wt. Unit Wt. Intercept Friction Angle (deg) 30.0 Pore Pressure Piez. Pressure Const-ant Surface No. (pcf) (pcf) (psf) 1 125.0 130.0 150.0 2 125.0 130.0 200.0 3 130.0 130.0 200.0 1 PIEZOMETRIC SURFACE(S) SPECIFIED 0.0 32.0 Unit Weight of Water= 62.40 (pcf) Piezometric Surface No. 1 Specified by Pore Pressure Inclination Factor 0.50 Point X-Water Y-Water No. (ft) (ft) 1 42.00 ·127.00 2 68.00 128.00 3 84.00 128.00 4 124.00 139."00 5 180.00 139.00 Param. (psf) 0.00 0.0 0.00 0.0 o:oo 0.0 5 Coordinate Points A Critical Failure Surface Searching Method, Using A Random Technique F0r Generating Circular Surfaces, Has Been Specified. 600 Trial Surfaces Have Been Generated . No. 1 0 1 20 Surface (s) Initiate (s) From Each Of 30 -Poi;nts Equally Spaced Along The Ground Surface Between X 58.00(ft) and X 68.00(ft) Each Surface Ten:ninates Between X 118. 00 (ft) • •. ,.· P:\leighton\980000-l\980160.D03\eng\cantar-2.0UT Page 2 and X ~ 130.00(ft) Unless Further Limitations Were Imposed, The Minimum E·levation At Which A Surface Extends Is Y = 120.00(ft) 2,.00(ft) Line Segments Define Each Trial Failure Surface. Following Are Displayed The Ten Most Critical Of The Trial Failure Surfaces Evaluated. They Are Ordered -Most Critical First. **Safety Factors Are Calculated By The Modified Bishop Method Total Number of Trial Sm;fates Eva],uated =. 600 Statistical Data On All Valid FS Values·: FS M~x = 5.881 FS Min= 1.131 · FS Ave= 1.919 Standard Deviation= 0.844 Coefficient of Variation Failure Surface Specified By 34 Coordinai;e Points Point X-Surf Y-Surf No. (ft) (ft) 1 65.93 127.92 2 67.64 126.88 3 69.39 125.92 4 ~1.19 125.04 5 73.03 124.25 6 14.90 123.54 7 76.80 122.91 8 78.72 122.37 9 80.67 121.93 10 82.64 121.57 11 84.62 121.30 12 86.61 121.12 13 88.61 121.04 14 90.61 121.04 15 92.61 121.14 . 16 94.60 -121.33 17 96.58 121.61 18 98.55 121.98 19 100.49 122.44 20 102.~2 122.99 21 104 .31 123. 63 22. 106.18 124.35 23 108.01 125~16 24 109.80 126.05 25 111.55 127.02 26 113.25 128.07 27 114.90 129.19 28 116.50 130.39 29 118.04 131.67 30 119.53 133.01 31 120.94 134.42 32 122.30 135.89 33 123.58 137.42 34 124.02 137.99 * * 43.96 % Circle Center At X = 89.47 Factor of Safety y = 164 .. 68 ; and Radius 43.65 *** 1.131 *** Individual data on the 40 slices Water Water Tie Tie Earthquake Force Force Force Force Force Surcharge Slice Width Weight Top Bot Norm Tan Hor Ver Load No. (ft) (lbs) (lbs) (lbs) (ibs) (lbs) (lbs) (lbs) (lbs) 1 1. 7 122.7 0.0 68.9, 0. 0. 0.0 0.0 0.0 2 0.4 56.6 0.0 31.0 0. 0. 0.0 0.0 0.0 3 1.1 243.8 0.0 122.7 Q' 0. 0.0 0.0 0.0 4 0.3 97.0 0.0 0.0 0: 0. 0.0 0.0 0.0 5 1.8 723.5 0.0 0.0 0. 0. 0.0 0.0 0.0 6 0.8 423.9 0.0 0.0 0. 0. o.o 0.0 0.0 7 1.0 620. 9 0.0 0.0 0. 0. 0.0 0.0 0.0 8 1. 9 1357.5 0.0 0.0 0'. 0. 0.0 0.0 0.0 9 1. 9 1659.2 0.0 0.0 o. 0. 0.0 0.0 0.0 10 1.9 1946.8 0.0 0.0 0. 0. 0.0 0.0 0.0 P:\leighton\980000-1\980160.003\eng\cantar-2.0UT Page 3 ·:·· 11 1. 9 2217.1 0.0 0.0 0. 0. 0.0 0.0 0.0 12 2.0 2467.4 0.0 0.0 o. 0. 0.0 0.0 0.0 13 1. 4 1828.9 o~o 0.0 0. . 0. 0.0 0.0 0.0 14 0.6 865.7 0.0 0.0 0. 0. 0.0 0.0 0.0 15 2.0 2899.9 0.0 0.0 0. 0. 0.0 0.0 0.0 16 2. O· 3081. 2 0.0 0.0 0. 0. 0.0 0.0 0.0 17 2.0 3234.2 0.0 0.0 0. 0. 0.0 0.0 0.0 18 2.0 33"57.6 0.0 0.9 0. o. Q.O 0.0 0.0 19 2.0 3450.3 0.0 0.0 0. 0. 0.0 0.0 o.·o 20 2.0 3511. 7 0.0 0.0 0. O·. 0.0 0.0 0.0 21 2.0 3541.6 0.0 0.0 0. 0. 0.0 0.0 0.0 22 1. 9 3540.0 0.0 0.0 0. 0. 0.0 0.0 0.0 23 1.9 3507.6 0.0 0.0 0. 0. 0.0 0.0 0.0 24 1. 9 3445.0 0.0 0.0 0. 0. 0.0 0.0 0.0 25 1.9 3353.4 0.0 0.0 0. 6. 0.0 0.0 0.0 2-6 1.8 3234.5 0.0 0.0 0. o. 0.0 0.0 0.0 27 1.8 3090.0 0.0 0.0 0. 0. 0.0 0.0 0.0 28 1. 7 2922.0 0.0 o.o 0. 0. 0.0 0.0 0.0 29 0.5 739.9 0.0 0.0 b. 0. 0.0 0.0 0.0 30 1. 2 1950.3 0.0 0.0 0. 0. 0.0 0.0 0.0 31 0.9 1358.5 0.0 0.0 0. o. 0.0 0.0 0.0 32 0.7 978.2 0.0 389.3 o. 0. 0.0 0.0 0.0 33 1.6 1970.3 0.0 833.8 0. 0. 0.0 0.0 o.o 34 1.5 1605.4 0.0 736.8 o. 0. 0.0 0.0 0.0 35 1.5 1247.6 0.0 629.4 0. 0. ·6. o 0.0 0.0 36 1.4 900.9 0.0 511. 8 0. o. 0.0 0.0 0.0 37-1. 4 569.3 0.0 384.2 0. o. O.o 0.0 0.0 38 1.3 253.7 37.4 247.0 0. 0. 0.0 0.0 0.0 39 0.4 18.3 22.0 51.5 0. 0. 0.0 0.0 o.o 40 0.0 o .. 0 1.2 2.0 0. 0. 0.0 0.0 0.0 Failure Surface Specified By 35 Coordinate Points ···:·· Point X-Surf Y-Surf 'No. (ft) (f-t) 1 64.55 127.87 2 66.30 126. 89 '3 68 .. 08 125.99 4 69.90 125.16 5 71. 75 124. 40 6 73.63 123. 72 7 75.54 123 .. 12 8 77.47 122.59 9 79 .. 42 122.15 10 81.39 121.78 11 83 .. 37 i-21.49 12 85.35 121. 28 13 87.35 121.16 14 89.35 121.11 15· 91.35 121.15 16 93.35 121.27 17 95.34 121. 46 18 97.32 121. 74 19 99.28 122.10 20 101. 24 122.54 21 103.17 123.06 22 105.08 123.65 23 106.96 124.32 24 108.82 125.07 25 110.64 125.89 26 112. 43 1.26. 79 27 114 .18 127.76 28 115.89 128.79 29 117. 55 129.90 30 119.17 131.07 e:::. 31 120.75 132.31 32 122.27 133.61 33 123.73 134.97 34 125 .14 136.39 P:\leighton\980000-1\980160.003\eng\cantar-2.OUT Page 4 ••• 35 126.10 137.44 Circle Cente:i; At X = 89.46 ; y = 170.42 and Radius 49.31 Factor of Safety *** 1.132 *** Failure Surface Specified By 34 Coordinate Points Point X-Surf Y-Surf No. (ft) (ft) 1 64.21 127.85 2 65.90 126.79 3 67. 64 125.81 4 69.43 124.91 5 71. 26 124.09 6 73.12 123.37 7 75.01 122.73 8 76.94 122.18 9 78.89 121. 73 10 80.85 121. 36 11 82.83 121.10 12 84.83 120.92 13 86.83 120.84 14 88.83 120.86 15 90.82 120.96 16 92.81 121.17 17 94. 79 121.47 18 96.75 121.86 19 98.69 122.34 20 100.61 122.92 21 102.49 123.58 22 104.35 124.33 23 106.16 125.17 24 107.93 126 .10 • 25 109.66 127.J.,1 26 111. 34 128.20 27 112. 96 129.36 28 114. 53 130.61 29 116.04 131. 92 30 117.48 133.31 3i 118. 85 134. 7 6 32 120.16 136.27 33 121. 39 137.85 34 121. 76 138.37 Circle Center At X = 87.52 ; y = 163.04 ; and ·Radius 42.21 Factor of Saf~ty *** 1.1'37 *** Failure Surface Specified By 35 Coordinate Points Point X-Surf Y-Surf No. (ft) (ft) 1 66.97 127.96 2 68. 71 i26.98 3 70.49 126.07 4 72.30 125.23 5 74.15 124. 46 6 76.03 123.77 7 77.93 123.15 8 79.86 122.61 9 81. 80 122.15 10 83. 76 121.77 :).1 85.74 121. 46 12 87.73 121.23 13 89. 72 121.09 14 91. 72 121.02 15 93. 72 121.03 16 95. 72 121.12 • 17 97. 71 121. 29 18 99.70 121.55 19 101.67 121.,88 20 103.63 122.28 P:\leighton\980000-1\980160.003\eng\cantar-2.0UT Page 5 •• Zl 105.57 122.77 22 107. 4.9 123.33 23 109.38 123. 97 24 :I.11.25 124.69 25 113. 09 125.48 26 114.89 126. 34 27 116.66 127.27 28 118. 39 128.28 29 120.08 129.35 30 121. 72 130.49 31 123.32 131.69 32 124.87 132.95 33 .126.37 134.28 34 127.81 135. 66 35 128.81 136.70 Circle Center At X = 92.41 ; y = 171.10 ; and Radius 50.08 Factor of Safety *** 1.140 *** Failure Surface Specified By 38 Coordinate Points Poj.nt X-Su·rf Y-.Surf No. (ft) (ft) 1 62.14 127.77 2 63.92 126.87 3 65.74 126.04 4 67.58 125.26 5 69.45 124.54 6 71.34 123.89 7 73.25 123.31 8 75.19 122·. 79 .9 77.13 122.33 10 79.10 121.95 •• 11 81.07 121.63 12 83.05 121.37 13 85.04 121.18 14 87.04 121.07 15 89.04 12J,.02 16 91.04 1.21.03 17 93.04 121 .. 12 18 95.03 121.27 1'9 97.02 121. 49 20 99.00 121. 78 21 100.97 122.13 22 102.92 :!.22.55 23 104.86 123.04 24 106.79 123.59 25 108.69 124.21 26 110. 57 124.89 27 112. 42 125.64 28 114 .25 126. 45 29 116. 05 127.32 30 117.82 128.25 31 119.56 129.23 32 121.27 130,.28 33 122.93 131.~9 34 124.56 132.55 35 126.15 133. 77 36 127.70 135.03 37 129.20 136.36 38 129.40 136.55 Circle Center At X = 89.54 ; y = 179.92 ; and Radius 58.90 Factor of Safety *** 1.141 *** Failure Surface Specified By 37 Coordinate Points ••• Point X-Surf Y-Surf No. (ft) (ft) 1 60. 76 127. 72 2 62.51 126.76 P:\leighton\980000-1\980160.003\eng\cantar-2.0UT Page 6 ·---3 64.31 125.87 4 66.13 125.05 5 67.98 124.30 6 69.86 123.62 .7 71. 77 123.02 8 73_. 70 122.48 9 75.65 122.03 10 77.61 121. 65 11 79. 58 121. 34 12 81. 57 121.11 13 83.57 120.96 14 85.56 120.88 15 87.56 120.88 16 89.56 120.96 17 91.56 121.11 18 93.54 121. 34 19 95.52 121. 65 20 97.48 122.03 21 99.43 122. 4.9 22 101. 36 123.02 23 103.26 123.62 24 105.14 124.30 2-5 107.00 125.05 26 108.82 125.87 27 110.61 126.77 28 112. 37 127.72 29 114.08 12.8. 75 30 115.76 129.84 31 117.39 131. 00 32 118.98 132 .21 33 120.52 133.49 ··: 34 122.01 134.83 35 123.45 136.22 36 124.83 1.37. 66 37 124.91 137.75 Circle Center At X = 86.56 ; Y'·= 172. 87 ; and Radius 52.00 Factor of Safety *** 1..142 *** Failure Surface Specified By 38 Coordinate Points Point X-Surf Y-Surf No. (ft) (ft) 1 58.35 127.63 2 60.12 126. 71 3 61.93 125.85 4 63. 76 125,05 5 65. 62 124.32 6 67.51 123.66 7 69.42 123.06 8 71.34 122.52 9 73.29 122.06 10 75.25 121.66 11 77.22 121.33 12 79.21 121.,07 13 81.20 120.88 14 83.19 120.75 15 85.19 120.70 16 87.19 120. 72 17 89.19 120.80 18 91:10 120.96 19 93.17 121.18 20 95.15 121.48 21 97.12 121. 84 22 99.07 122.27 •• .23 101.01 122.77 24 102.93 123.33 25 10~.82 123.96 26 106.70 124.66 P:\leighton\980000-1\980160.003\eng\cantar-2.OUT Page 7 ···: 27 108.55 125.42 :;: 28 110.37 126.25 29 112.16 127.14 30 113.92 128.09 31 115. 65 129.10 32 117. 34 130.17 33 118.99 131. 29 34 120. 60 132.48 35 122.17 133. 72 36 123.69 135.01 37 125.17 136.36 38 126.24 137.40 Circle Center At X = 85.12 ; y = 178.21 ; and Radius 57.51 Factor of Safety *** 1.143 *** Failure Surface Specified By 39 Coordinate Points Point X-Surf Y-Surf No. (ft) (ft) 1 58.69 127.64 2 60.48 126. 74 3 62.29 1.25.90 4 64.14 125.13 5 66.00 124 .. 41 6. 67.89 123.76 7 69.80 i23.17 8 71. 73 122.64 9 73.68 122.18 10 75.64 121. 79 11 77. 61 121. 46 12 7-9.60 121.19 13 81. 59 121. 00 ••• 14 83.58 120.87 :::= 15 85.58 120.80 16 87.58 120.80 17 89.58 120.8'7 18 91.58 121.01 19 93.56 121.21 20 95.55 121. 48 21 97.52 121.82 22 99.48 122.22 23 10.1,.42 122 .-68 24 103.35 123 .. 21 25 105.26 123.81 26 107.15 124.47 27 109.02 125.19 28 110.86 125.97 29 112. 67 126. 81 30 114.45 127. 72 31 116. 21 128. 68 32 117.93 129.70 33 119. 61 130.78 34 :).21.26 131.91 35 122.87 133 .10 36 124.44 134.34 37 125.96 135.63 38 127.45 136.97 39 127.53 137.05 Circle Center At X = e6.5o ; y = 180.70 and Radius 59.90 Factor of Safety *** 1.143 *** Failure Surface Specified By 35 Coordinate Points Point X-Surf Y-Surf No. (ft) (ft) 1 64.21 127.85 2 65.96 126.89 3 67.75 126.01 ••• 4 69.58 125.19 • • • P:\leighton\980000-1\980160.003\eng\cantar-2.0UT Page 8 5 71.44 124.45 6 73.32 123.78 7 75.23 123.19 8 77.17 122.68 9 79.12 122.24 10 81. 09 121. 88 · 11 83.07 121.60 12 85.06 121.40 13 87.05 121.28 14 89.05 121.24 15 91.05 121.28 16 93.05 121.40 17 95.04 121.60 18 97.02 121.88 19 98.99 122.24 20 100.94 122.67 21 102.87 123.19 22 104.78 123.78 ?3 106.67 124.45 24 108.52 125.19 25 110.35 126.00 26 112.14 126.89 27 li3.90 127.85 28 115.61 128.88 29 117.29 12~.97 30 118.91 131.14 31 120.49 132.36 32 122.02 133.65 33 123.50 135.00 34 124.92 136.41 35 125.93 137.48 Circle Center At X = 89.06; Y == 171.23 ; and Radius Factor of Si;ifety . *** 1.144 *** Failure Surface Specified By 38 Coordinate Points Point X-Surf Y-Surf No. (ft) (ft) 1 60.41 127.71 2 62.21 126.83 3 64.03 126.00 4 .65.88 125.24 5 67.75 124.53 6 69.65 123.89 7 71.56 123.31 8 73.49 122.80 9 75.44 122.34 10 77.40 121.95 11 79,37 121.62 12. 81.36 121.36 13 83.35 121.16 14 85.34 121.03 15 87.34 120.96 16 89.34 120.96 17 91.34 121.02 18 93.34 121.15 19 95.33 121.34 20 97.31 121.60 21 ·99.28 121.92 22 101.25 122.31 23 103.20 122.76 24 105.13 123.27 25 107.04 123.85 26 108.94 124.49 27 110.81 125.18 28 112.66 125.94 29 114.49 126.76 30 116.29 127.64 49.99 • • • P:\leighton\980000-1\980160.003\eng\cantar-2.OUT Page 9 31 118. 05 32 119.79 33 121. 49 34 123.16 35 124.79 36 126.38 37 127.93 38 129.33 Circle Center At X = Factor of Safety *** 1.146 *** 128.58 129.57 130.62 131. 72 132.88 134.09 135.35 136.57 88.41 Y 182.37 **** END OF GSTABL7 OUTPUT**** and Radius 61. 42 • LEIGHTON AND ASSOCIATES SURFICIAL SLOPE STABILITY ANALYSIS Project No.: 980160-004 Project: Case: Benteq Cantarini Embankment Evaluation 3:1 Slope -Compacted Fill@ 90% R.C. Depth of Saturation (ft), Z Buoyant Unit Weight of Soil (pcf), Yb Total Unit Weight of Soil (pcf), Yt Slope Angle, a Angle of Internal Friction, q, Cohesion (psf), c Force Tending To Cause Movement: F0 = Zy1 sin 2a/2 Force Tending To Resist Movement: FR= Zyb cos2 a tan q, + ( c) = 4 = 62.6 = 125 = 18.4 = 30 = 150 = 149.76 lb/ft = 280.16 lb/ft F.S.: 2Zyb coS2 a tan q, +2c Zytsin 2a F.S.;: 1.9 Project Name : Benteq/Canterini SURFICIAL STABILITY Project Nurnber: 980160-004 Designed/Checked : AXT/SAC Figure: A-1 • • • • -= .. : .. •• Leightonand Associates,Ihc. GENERALEARTHWORKAND GRADINGSPEOFICATIONS Pagel of 6 LEIGHTON AND AS SOCIA fES,INC. GENERAL EARTHWORK AND GRADING SPECIFICATIONSFOR ROUGH GRADING 1.0 General 1.1 1.2 3030.1094 Intent: These General Earthwork and Grading Specifications are for the grading and earthwork shown on the approved grading plan(s) and/or indicated in the geotechnical report(s). These Specifications are a part of the recommendations contained in the geotechnical report(s). In case of conflict, the specific recommendations in the geotechnieal report shall supersede these more general Specifications. Observations of the earthwork by the project Geotechnical Consultant during the course of grading may result in new or revised recommendations that could supersede these specifications or the recommendations in the geotechnical report( s). . The Geotechnical Consultant of Record: Prior to commencement of work, the owner shall employ the Geotechnical Consultant of Record (Geotechnical Consultant). The Geotechnical Consultants shall be responsible-for review_ing the approved geotechnical report( s) and accepting the adequacy of the preliminary geotechnical findings, conclusions, and recommendations prior to the commencementof the grading. Prior to commencement of grading, the G_eotechnical Consultant shall review the "work plan" prepared by the Earthwork Contractor (Contractot).and schedule sufficient personnel to perform the appropriate level of observation, mapping, and c0mpaction testing. During the grading and earthwork operations, the Geotechnical Consultant shall observe, map, and document the subsurface exposures to verify the geotechnical design assumptions. If the observed conditions are found to be significantly different than the interpreted assuniptions during the design phase, the Geotechnical Consultant shall inform the· owner, recommend appropriate changes in design to accommodate the observed conditions, and notify the review agency where required. Subsurface areas to be geotechhically observed, mapped, eievations recorded, and/or tested include natural ground after it has been cleared for receiving fili but before_fill is placed, bottoms of all "remedial removal" areas, all key bottoms, and benches made on sloping ground to receive fill. The Geotechnical Consultant shall observe the moisture-conditioningand processing of the sµbgrade and fill materials and perform relative compaction testing of fill to determine the attained level of compaction. The Geotechnical Consultant shall provide the test results to the owner and the Contractor on a routine and frequent basis . ••••• •,.:· . •• Leighton and Asi,ociates, Inc. GENERALEARTHWORKAND GRADINGSPEOFICATIONS Page2of 6 2.0 3030.1094 1.3 The Earthwork Contractor: The Earthwork Contract-or (Contractor) shall be qualified, experienced, and knowledgeable in earthwork logistics, preparation and processing of ground to receive fill, moisture-conditioning and processing of fill, and compacting fill. The C0ntractor shall review and accept the plans, geotechnical report(s), and these Specifications prior to commencement of grading. The Contractor shall be solely responsible for performing the grading in accordance with the plans and specifications. The Contractor shall prepare and submit to the owner and the Geotechnical Consultant a work plan that indicates the sequence of earthwork grading, the number of "spreads" of work and the estimated quantities of daily earthwork contemplated for the site prior to commencement of grading. The Contractor shall-inform the owner and the Geotechnical .Consultant of changes in work schedules and updates to the work plan at least 24 hours in advance·of such changes so that appropriate observations and tests can be planned and accomplished. The Contractor shall not assume that the Geotechnical Consultant is aware of all grading operations. The Contractor shall have the sole responsibility to provide adequate equipment and .methods to accomplish the earthwork in accordance with the applicable grading codes and agency ordinances, these Specifications, and the recommendations in the approved geotechnical report(s) and grading plan(s). If, in the opinion of the Geotechnical Consultant, unsatisfactory conditions, such as unsuitable soil, improper moisture condition, inadequate compaction, insufficient buttress key size, adverse weather, etc., are resulting in a quality of work less than required in these specifications, the Geotechnical Consultant shall reject the work and mf!,y recommend to the owner that construction be stopped until the conditions are rectified . Preparation of Areas to be Filled 2.1 Clearing and-Grubbing: Vegetation, such as brush, grass, roots, and other deleterious material shall be sufficiently removed and properly disposed of in a method acceptable to the owner, governing agencies, and the Geotechnical Consultant. The Geotechnical Consultant shall evaluate the extent of these removals depending on specific site conditions. Earth fill-material shall not contain more than 1 percent of organic materials (by volume). No fill lift shall contain more than 5 percent of organic matter. Nesting of the organic materiali; shall not be allowed. If potentially hazardous materials are encountered, the Contractor shall stop work in the affected area, and a hazardous material specialist shall be informed immediately for proper ···evaluation and handling of these materials prior to continuing to work in that area. As presently defined by the State-of California, most refined petroleum products (gasoline, diesel fuel, motor oil, grease, coolant, etc.) have· chemical constituents that are considered to be hazardous waste. As such, the indiscriminate dumping or spillage of these fluids onto the ground may constitute a misdemeanor,.punishable by fines and/or imprisonment, and shall not be allowed . • •• •• Leighton and Associates, Inc. GENERALEARTHWORKAND GRADINGSPEOFICATIONS Page3 of 6 2.2 Processing: Existing ground that has been declared satisfactory for support of fill by the Geotechnical Consultant shall be scarified to a minimum depth of 6 inches. Existing ground that is not satisfactory shall be overexcavated as specified in the following section. Scarification shall continue until soils are broken down and free of large clay lumps or clods and the working surface is reasonably uniform, flat, and free of uneven features that would inhibit uniform compaction. 2.3 Overexcavation: In addition to removals and overexcavations recommended in the approved geotechnical report(s) and the grading plan, soft,_ loose, dry, saturated, spongy~ organic-rich, highly--fractured or otherwise unsuitable ground shall be overexcavated to competent ground as evaluated by the Geotechnical Consultant during grading. 2.4 Benching: Where fills-are to be placed on ground with slopes steeper than 5: 1 (horizontal to vertical units), the ground shall be stepped or benched. Please see the Standard Details for a graphic illustration. The lowest bench or key Shall be a minimum of 15 feet wide and at least 2 feet deep, _into competent material as evaluated by the Geotechnical Consultant. Other benches shall be excavated.a minimum height of 4 feet into competent material or as otherwise recommended by the Geotechrtical Consultant. Fill placed on ground sloping flatter than 5: l shall also be benched or otherwise overexcavated to provide a flat subgrade for the fill. 2.5 Evaluation/ Acceptance of Fill Areas: All areas to receive fill, including removal and processed areas, key bottoms, and benches, shall be observed, mapped, elevations recorded, and/or tested prior to being accepted by the Geotechnical Consultant as suitable to receive fill. The Contractor shall obtain a written acceptance from the Geotechnical .-.-Consultantpriorto fill placement. A licensed surveyor shall provide the survey control for determining elevations of processed areas,keys, and benches. 3.0 Fill Material 3030.1094 3 .1 General: -Material to be used -a~ fill shall be essentially free of organic matter and-other deleterious substances-evaluated and-accepted by the Geotechnical Consultant prior to placement. Soils of poor -quality, such as those. with,.unacceptable gradation, high expansion potential, or low strength shall be placed in areas acceptable to the Geotechnical Consultant or mixed with other soils to achieve satisfactory fill material. 3 .2 Oversize: Oversize material defined as rock, or other irreducible material with a maximum · dimension greater than 8 inches, shall not be buried or placed in fill unless location, · materials, and · placement methods· are specifically accepted by the Geotechnical Consultant. Placement operations shall be such that nesting of oversized material does not occur and such that oversize material is completely surrounded by compacted or densified fill. Oversize material shall not be placed w1.thin 10 vertical feet of finish grade or within 2 feet of future utilities or underground construction . • •• • Leighton and Associates,Inc. . GEI\!ERALEARTHW0RKAND GRADINGSPEOFICATI0NS Page4of6 3..3 Import: If importing of fill material is required for grading, proposed import material shall meet the requirements of Section 3 .1. The potential import source shall be given to the Geotechnical Consultant at least 48 hours (2 working days) before importing begins so that its suitabilitycan be determined and appropriate tests performed. 4.0 Fill Placement and Compaction 4.1 Fill Layers: Approved fill material shall be placed in areas prepared to receive fill (per Section 3.0) in near-horizontal layers not exceeding 8 inches in loose thickness. The Geotechnical Consultant may accept thicker layers if testing indicates the grading procedures can adequately compact the thicker layers. Each layer shall be spread evenly · and mixed thoroughly to attain relative uniformity of material and moisture throughout. . 4.2 Fill Moisture Conditioning: Fill soils shall be watered, dried back, blended, and/or mixed, as necessary to attain a relatively uniform moisture content at or slightly over optimum. ·Maximum density and optimum soil moisture content tests shall be performed in accordance with the American Society of Testing and Materials (ASTM Test M~thod D1557-91). .. 4.3 Compaction of Fill: After each layer has been moisture-conditioned, mixed, and evenly spread, it shall be uniformly compacted to not less than 90 percent of maximum dry density (ASTM Test Method D1557-91). Compaction equipment shall be adequately sized and be either specifically designed for soil compaction or of proven reliability to efficiently achieve the specified level of compaction with uniformity. 3030.1094 4.4 Compaction of Fill Slopes: In addition to normal compaction procedures specified above, compaction of slopes shall be accompiished by backrolling of slopes with sheepsfoot . rollers. at_ increments of 3 to 4 feet i!]. fill elevation, or by other methods producing satisfactory results acceptable to the Geotechnical Consultant. Upon completion of grading, relative compaction of the fill, out to the slope face, shall be at least 90 percent of maximumdensityper ASTMTestMethod D1557-91. 4.5 Compaction Testing: Field tests for. moisture content and ·relative compaction of the fill soils shall be performed by the Geotechnical Consultant. Location and frequency of tests shall be at the Consultant's discretion based on-field conditions encountered. Compaction test locations will not necessarily be selected ort a random basis. Test locations shall be selected to verify adequacy of compaction levels in areas that are judged to be prone to inadequate compaction ( such as close to slope faces and at the fill/bedrock benches) . ·-·· •• .;.:· Leighton-and Associates, Inc. GENERAL EARTHWORK AND GRADING SPECIFICATIONS Page5 of 6 5.0 6.0 3030.1094 4.6 Frequency of Compaction Testing: Tests shall be taken at inte~als not exceeding 2 feet in vertical rise and/or 1,000 cubic yards of compacted fill soils embankment. In addition, as a guideline, at least one test shall be taken on slope faces for each 5,000 square feet of slope face and/ot each 10 feet of vertical height of slope. The Contractor shall assure that fill . construction is such that the testing schedule can be accomplished by the Geotechnical Con~ultant. The Contractor shall stop or slow down the earthwork construction if these minimum standards are not met. 4. 7 Compaction Test Locations: The Geotechnical Consultant shall document the approximate elevation and horizontal coordinates ofeach test location. The Contractor shall coordinate with the project surveyor to assure that sufficient grade stakes are established so that the Geotechnical Consultant can determine the test locations with sufficient accuracy. At a minimum, two grade stakes within a horizontal distance of 100 feet and vertically less than 5 feet apart from potential test locations shall be provided. Subdrain Installation Subdrain systems shall be installed in· accordance with the approved· geotechnical report(s), the grading plan, and the Standard Details. The Geotechnical Consultant may recommend additional subdrains and/or changes in subdrain extent, location, grade, or material depending on conditions encountered during gra,ding. All subdrains shall be surveyed by a land surveyor/civil engineer for line and grade after installation and prior to burial. Sufficient time should be allowed by the Contractor for these surveys. Excavation Excavations, as well as over-excavation for remedial purposes, shall be evaluated by the Geotechnical Consultant during grading. Remedial removal depths shown on geotechnical plans are estimates only. The actual extent of removal shall be determined. by the Geotechnical Consultant based on the field evaluation of exposed conditions during grading. Where fill-over-cut slopes are to be graded, the cut portion of the slope shall be made, evaluated, and accepted by the Geotechnical Consultant prior to placement of materials for construction of the fill portion of the slope, unless otherwise recommended by the Geotechnical Consultant. •;:: .. •• ·-· •• Leighton and Associates, Int. GENERALEARTHWORKANb GRADING SPECIFICATIONS Page6of6 7.0 3030.1094 Trench Backfills 7.1 The Contractor shall follow all OHSA and Cal/OSHA requirements for safety of trench e4-cavations. 7.2 All bedding and backfill of utility trenches shall be done in accordancewith the applicable provisions of Standard Specifications of Public Works Construction. Bedding material shall have a Sand Equivalent greater than 30 (SE>30). The bedding shall be placed to 1 foot over the top of the conduit and densified by jetting. Backfill shall be placed and densified·to a minimum of 90 percent of maximum from 1 foot above the top of the conduit to the surface. 7.3 The jetting of the bedding around the conduits shall be-observed by--the Geotechnical Consultant. 7.4 The Geotechnical Consultantshall test the trench backfill for relative compaction. At least one test should be made for every 3 00 feet of trench and 2 feet of fill. -7.5 Lift thickness of trench backfill shall not exceed those allowed m the Standard Specifications of Public Works Construction unless the Contractor can demonstrate to the Geotechnical Consultant that the fill lift can be compacted to the minimum relative compaction by his alternative equipmentl:!-nd method . •••• FILL SLOPE PROJECTED PLANE 1 TO 1 MAXIMUM FROM TOE OF SLOPE TO APPROVED GROUND EXISTING GROUND SURFACE FILL-OVER-CUT SLOPE CUT-OVER-FILL SLOPE PROJECTED PLANE 1 TO 1 MAXIMUM . FROM TOE OF SLOPE TO APPROVED GROUND 15' MIN. .1 LOWEST BENCH (KEY) KEYING AND BENCHING REMOVE UNSUITABLE MATERIAL REMOVE UNSUITABLE MATERIAL CUT FACE SHALL BE CONSTRUCTED PRIOR TO FILL PLACEMENT REMOVE UNSUITABLE MATERIAL FOR SUBDRAINS SEE STANDARD DETAIL C BENCHING SHALL BE DONE WHEN SLOPE'S ANGLE IS EQUAL TO OR GREATER THAN 5: 1. MINIMUM BENCH HEIGHT SHALL BE 4 FEET AND MINIMUM FILL WIDTH SHALL BE 9 FEET. GENERAL EARTHWORK AND GRADING SPECIFICATIONS STANDARD DETAILS A LEIGHTON AND ASSOCIATES ••• • • • OVERSIZE ROCK IS LARGER THAN 8 INCHES IN LARGEST DIMENSION. FINISH GRADE EXCAVATE A TRENCH IN THE COMPACTED FILL OEEP ENOUGH TO BURY ALL THE ROCK. GRANULAR MATERIAL 10 BE DEN SI Ff ED IN PLACE BY FLOODING OR JETTING. DETAIL • BACKFILL WITH GRANULAR SOIL JETTED OR FLOODED IN PLACE TO FILL ALL THE VOIDS. • DO NOT BURY ROCK WITHIN 10 FEET OF FINISH GRADE . . • WINDROW OF BURIED ROCK SHALL BE PARALLEL TO THE FINISHED SLOPE. --_;._ JETTED OR FLOODED GRANULAR MATERIAL TYPICAL PROFILE ALONG WINDROW OVERSIZE ROCK DISPOSAL GENERAL EARTHWORK AND GRADING SPECIFICATIONS STANDARD DETAILS B LEIGHTON AND ASSOCIATES CALTRANS CLASS 2 PERMEABLE OR #2 ROCK (9FT"3/FT) WRAPPED IN FILTER_ FABRIC- -SUSDRAIN TRENCH SEE DETAIL BELOW FILTER FABRIC REMOVE UNSUITABLE MATERIAL (MIRAFI 140N OR APPROVED EQUIVALENT)• COLLECTOR PIPE SHALL BE -MINIMUM 6" DIAMETER SCHEDULE 40 PVC PERFORATED PIPE. SEE STANDARD DETAIL D FOR PIPE SPECIFICATIONS SUBPBAIN PEIAlL DESIGN FINISH GRADE -----------------____ -__-_-_-_-_-_-_-_:_-_-_ 10' MIN. -----------------BACKFILL -=:=:::= i~~~~~i~;~t;~~== ;:~~:~~;~;: ~;~~;~;~;==-- , FILTER FABRIC (MIRAFI 140N OR APPROVED EQUIVALENT) ~=~~=========== .-•. ~ :-0 •.: \ : ". ". • • : •• • : 0 • :. 0 0 • • • ..--CAL TRANS CLASS 2 PERMEABLE l======if:f=_====~=::;::::;::::;::::===:::::;::::::;:~:;;::: .::::0 :::: 0=:=::-OR #2 RO<;:K (9FT"3/FT) WRAPPED I ---0 • -• 0 • 0 • 0 0 -. 0 • IN FILTER FABRIC I I-20' MIN.--5' MIN. --PERFORATED "' ---. · I 6" 0 MIN. PIPE NONPERFORA TED 6" 0 MIN. DETAIL -Of CANYON SUBDRAIN OUTLET CAN-YON SUBDRAINS GENERAL EARTHWORK AND GRADING SPECIFICATIONS STANDARD DETAILS C LEIGHTON AND ASSOCIATES OUTLET PIPES 4" 0 NONPERFORA TED PIPE, 100' MAX. O.C. HORIZONTALLY, .30' MAX C>.C. VERTICALLY 12" MIN. OVERLAP FROM THE TOP HOG RING TIED EVERY 6 FEET CAL TRANS CLASS II PERMEABLE OR #2 ROCK (3 FT"3/FT) WRAPPED IN FILTER FABRIC 15'MIN. •I TRENCH LOWEST SUBDRAIN SHOULD BE SITUATED AS LOW AS POSSIBLE TO 'ALLOW SUITABLE OUTLET T-CONNECTION FOR COLLECTOR PIPE TO OUTLET PIPE ~--4" MIN. BEDDING SUBDRAIN TRENCH DETAIL SUBDRAIN INSTALLATION -subdrain collector pipe shall be installed with perforation down or, unless otherwise designated by the· geatechni_col consultant. Outlet pipes shall be nan-perforated pipe. The subdr:oin pipe shall hove at least 8 perforations uniformly spaced per foot. Perforation shall be 1/4" ta 1/2" if drill hales ore used. All subdroin pipes shall hove a gradient of at least 2% towards the outlet. SUBDRAIN PIPE -Subdrain pipe shall be ASTM D2751, SDR 2.3.5 or ASTM D1527, Schedule 40, or ASTM D.3034, SDR 23.5, Schedule 40 Polyvinyl Chloride Plastic (PVC) pipe. All outlet pipe shall be placed in a trench no wide than twice the subdrain· pipe. Pipe shall be in soil of SE >/=:=.30 jetted or flooded in place except far the outside 5 feet which shall be native soil backfill. BUTTRESS OR REPLACEMENT FILL SUBDRAINS GENERAL EARTHWORK AND GRADING SPECIFICATIONS STANDARD DETAILS D LEIGHTON ANO ASSOCIATES •• RETAINING WALL WALL WATERPROOFING ~ PER ARCHITECT'S SPECiFICATIONS FINISH GRAOE ----------------------------·---------,--------------------------~-:-:::::::::~~-COMPACTED~~L~~:~~~~~~ WALL FOOTING ----- SOIL BACKFILL, COMPACTED TO 90 PERCENT RELATIVE COMPACTION BASED ON ASTM 01557 ------------------------------------------------------------· ----------------------------- ~t~~~~~~~~~~~~~~~~~~~ ~~~~:~:I:I:~ ~~:~:=-- ,-;= -:-------------:-:-:-:-:-:. 1-. -:--:-ii ----------· ,.. .-•• J I ------...... -. 6" MIN • ---------------.· ,, OVERLAP I =:=:=:=:=:=:=·· FILTER FABRIC ENVELOPE 0 • o • . ::::::::-::-.(MIRAFI 140N OR APPROVED I .0 .0 °o•OOI ~~~~~f' EQUIVALENT)** ,~ ~· ~IN ... IIJ----.3/4" TO 1-1/2" CLEAN GRAVEL I· . 0 ~I=====~ 0 • • • .• ~ ~::::~ ----4" (MIN.) DIAMETER P~RFORATED t. o ,-~ PVC PIPE (SCHEDULE 40 OR • o0 • . :::::=::: EQUIVALENT) WITH PERFORATIONS 0 -:-:-:-:-ORIENTED. DOWN AS DEPICTED I I:=:::=:=: MINIMUM 1 PERCENT GRADIENT · ~ ::::::::: TO SUITABLE OUTLET L . _: -=-=-=---.3" MIN. COMPEiENT BEDROCK OR MA TERI AL AS EVALUATED BY THE GEOTECHNICAL CONSULTANT NOTE: UPON REVIEW BY THE GEOTECHNICAL CONSULTANT, COMPOSITE DRAINAGE PRODUCTS SUCH AS MIRADRAIN OR J,-DRAIN MAY BE USED AS AN ALTERNATIVE TO GRAVEL OR CLASS 2 PERMEABLE MATERIAL. INSTALLATION SHOULD BE PERFORMED IN ACCORDANCE WITH MANUFACTURER'S SPECIFICATIONS. . RETAINING WALL - DRAINAGE DETAIL GENERAL EARTHWORK AND GRADING SPECIFICATIONS STANDARD DETAILS E LEIGHTON AND ASSOC1A TES • • •• .•. ,. ' ,, : ·-:.: ••• UPDATED GEOTECHNICAL MAPS, CANTARINI MULTI-FAMILY SITE AND HOLLY SPRINGS STREETS, TENTATIVE MAP FOR CANl'ARINI PROPERTY CARLSBAD, CALIFORNIA Prepared For BENTLEY-MONARCH, LLC 4729 East Sunrise PMB 433 · Tuscon, Arizona 85718 Project No. 980160-003 May 3, 2004 .... ____ Leighton and Associates, Inc. ---· A LEIGHTON GROUP COMPANY • :·-= . -· ._., • Leighton and Associates, Inc . A LEIGHTON GROUP COMPANY May 3, 2004 Project No. 980160-003 To: Bentley-Monarqh, LLC 4 729 East Sunrise PMB433 Attention: Subject: References: Tuscon, Arizona 85718 Mr. David Bentley Updated Geotechnical Maps, Cantarini Multi-Family Site and Holly Spring Streets, Tentative Map for Cantarini Property, Carlsbad, California GeoSoils, Inc., 2000a, Geotechnical Evaluation, ·Holly Springs Project, Carlsbad, San Diego County, California, W.O. 2929-A-SC, dated October 11, 2000 GeoSoils, Inc., 2000b, Addendum to Limited Geotechnical Evaluation, Holly Springs Project, Carlsbad, San Diego County, California, W.O. 2929-A-SC, dated October 16, 2000 Leighton and Associates, Inc., 2001a, Update Geotechnical Evaluation, Cantatj.ni Property, Carlsbad, California, Project No. 4980160 .. 003, dated July 9, 2001 Leighton and Associates, Inc., 2001b, Geotechnical Investigation for the Proposed C<;>llege Boulevard and Cannon Road, Carlsbad, California, Project No. 4990101- 002, dated March 20, 2001 O'Day Consultants, 2004, Tentative Map for Cantarini Property, Carlsbad, California, Sheets 1 to 27, revision dated February 2004 To facilitate review of the proposed grading associated with the development of the Cantarini Property, we have prepared updated Geotechnical Maps for the Multi,.Family site and the off-site Holly Springs streets. To prepare these maps, we have utilized geologic information contained in previous soils report (GeoSoils, 2000a and Leighton, 2001a) and the Tentative Map for the Cantarini Property (O'Day, 2004). The base map sheets from the Tentative Map Plans include Sheet 9 (Multi-Family site) and Sheets 19 to 21 (Holly Springs streets). The updated Geotechnical Maps (Plate 1 _through 4) are included 41. the pock~ts behind this cover letter. The 3934 Murphy Canyon Road, Suite B205 11 San Diego, ~A 92123-4425 858.292.8030 • Fax 858.292.0771111www.le1ghtongeo.com •:. ' : . 980160-003 geotechnical investigation for the Holly Springs site (GeoSoils, 2000a) is included as Attachment A ~d an addendum to that report (GeoSoils, 2000b) is included as Attachment B. If you have any questions regarding this document, please contact this office. We appreciate this opportunity to be of service. Respectfully submitted, LEIGHTON AND ASSOCIATES, INC. jjfJKl,J Randall K. Wagne~ Director of Geology Attachments: Plates 1 through 4: Geotechnical Maps (in pocket) Attachment A: Limited Geotechnical Evaluation of Holly Springs Project dated October 11, ~000 (GeoSoils, 2000a) Attachment B: Addendum to Limited Geotechnical Evaluation of Holly Springs Project dated October 16, 2000 (GeoSoils, 2000b) Distribution: (1) Addressee (1) Ladwig Design Group Attention: Mr._ B~b Ladwig -2- Leighton A • • ' ... ; . ~.-......... : :·· -~- '.• ... ···: ... ·.· 1•':. , ··:.·.· .. I~ • • .. ·. ...... . . "··.1. -~ .-' -~ . ,:•. . ·.-.,. ..-:-., . :: ... , ::···,,-.1• : .. .· ... ·. . '; . . : . ' ., : -~' ,, . : : ... - ,· ···: . . : ~~' .. . : ; .. ,·. ". :: t·: .; ~. -~ _ .. ._; . ·-=: ·.-: -,, ... · . ·:, :..,"' ···":. ·.:· : . :·. .. ·· .. ,: ·.-.- _,-:·:. . ·-·.· •,: . / .. ~. -. -i;~-1rj:-~ · GEo:i'eri_t·i'N~'ci~L---~~Ai.JAt1.b.~---~ . : . <'·.HOtLv·s·PRfNG.~iP:RciJecr,'~ ·:·--.:_:: ·;. . . CARL~$Ao; SAN· ·oi~~cf #PQN.tv{qAt1F..Q~N1A ·: -· · - • ", ;. • :: '• • • ., ' ." • I I ~ • • • , • ,• • ~ _. , ·.;. ., :-.:-'. ·FOF{ .. ',. _·_.··.-:_:MR.-:~lVuf,:~~~rt~EY:. ·: . . . . : '.7449 'IVIAGEL.LAl'J "S"FR.E·ET ·.:.·:' . ' ·: .. ·. ·. _: -CARLSBAD. ·'.CALH~.o:Fu;i1,f9200·9 ·;,-·'-.. -: .': _.,_·.·_·-_. __ ' ,,: .. ,, ...... -~ ..... -----·>:·/'i·;:·:_-._.·_.:'_-:·.-~·-_.·_:··.::_··.:, ___ .. : ... , . ,·_-.:,~~;b~.·2·~~-~~4~~c.·-_ · .,_9C;T?aE~: 1.1-;}ooo_;' :· - . ,•\ ·•:,. :.·-.:·· .... . '•' .... , . _: . ' .· ·-·· '.: . ~ 1.'" ',• '. '·:' · .. ,,•· .:. \ .,., ... · .. · :··· \ ·:-. - <, .. ·. •; . . .·,. -··: •• • Geotechnical • Geologic • Environmental 5741 Palmer Way • Carlsbad, California 92008 • (760) 438-3155 • FAX (760) 931-0915 October 11 , 2000 W.0. 2929-A-SC Mr. David Bentley 7 44~ Magellan Street Carlsbad, California 92009 Subject: Limited Geotechnical Evaluation, Holly Springs Project, Carlsbad, San Diego County, California · Reference: "Holly Springs, 56-R-1 Lots, 1 Multifamlly Lot, 3 Open Space Lots," sheets 1 and 2, Job L-1061, un~ated, by Ladwig Design Group. · Dear Mr. Bentley: In accordance with the request of Mr. Bob Ladwig (Ladwig Design Group),· and your authorization, GeoSoils, Inc. (GSI) has performed a limited geotechnical evaluation·of the subject site with regard to the proposed development. The purpose of our investigation -was to evaluate geotechnical conditions of the site ·and . present preliminary recommendations for grading and foundation design and construction for the proposed development The client should note that additional geotechnical studies will likely be warranted as detailed grading plans are available. EXECUTIVE SUMMARY Based on our review of the available data (Appendix A), field exploration, laboratory testing, c1nd limited geologic and engineering analysis, the proposed development appears to be feasible from a geotechnical viewpoint, provided the recommendations presented in the text of this report are properly incorporated into the design and construction of the project. The most significant elements of this study are summarized below: · • Pre!iminary laboratory test results indicate that site materials have a negligible potential for corrosion to concrete (i.e., sulfate content) and a severely high potential for corrosion to exposed ferrous materials (i.e., saturated resistiv_ity). • Our preliminary laboratory test results and field observations indicate that soils with a very low to possibly high expansion potential underlie the site. Foundation design and construction recommendations are. provided.herein, based on these conditions._ . •• ••• ••• • All alluvial and topsoil/colluvial soils, and the upper ± 1 to ±3 _feet of weathered bedrock are generally soft and potentially compressible and/or do not meet the current industry minimum standard of 90 percent (or greater) r~lative compaction and will require removal and recompaction. Based upon our limited subsurface evaluation, combined removaf depths are estimated to range between ± 1 to ± 7 feet below existing grade in areas proposed for settlement sensitive improvements. • Overall, the majority of the property is underlain by volcanic/metavolcanic bedrock of the Santiago Peak Volcanics intruded by a suit of granitic rock belonging to the southern Californi~ batholith. In the southwel?terly portion of the property, however, a sedimentary unit consisting of the Santiago Formation was encountered. Based · upon the anticipated, west-sloping ·contact between the younger sedimentary for_mation with the underlying granitic/volcanic bedrock, westerly-facing slopes may require stabilization in the vicinity of the multi-family area (i.e., Lot 1). Further evaluation is recommended or:ice 40-scale grading plans become available. • lh addition to backhoe test pits, a limited seismic refraction survey was performed to assess the rippability of bedrock materials. Results of the seismic refraction survey suggested dense to very dense, non-:-rippable bedrock materials exist at a depth, locally, of ± 15 to +30 feet. The rippability of the bedrock within the proposed grading limits is expected to be highly variable. For budgetary purposes, however, surface rock, hard layers and floaters (isolated hard zones and/or boulders) will likely be encountered that will be difficult to excavate with conventional grading equipment, and may require blasting from the surface. • The bulk of the materials derived from the weathered portion of the dense, hard bedrock are anticipated to disintegrate to approximately 12-to 24-inch diameters and smaller. Fills Should be well,.graded mixtures of fines with rock no larger than 12 inches in diameter. Rocks larger than 12 inches will require special handling for use in fills. For preliminary planning purposes, it can be assumed at least 50% of materials excavated from granitic and/or volcanic areas will generate oversized rock (i.e.; 12 inches or greater) requiring special handling. However, such an estimate should be used with caution, and not without consulting. a grading contractor experienced With residential development in hard tock terranes. Further evaluation is recommended once 40-scale grading plans become available. • ·Subsurface water is not anticipated to affect site develqpment, providing that the recomrnendations contained in this report are incorporated into final design and construction and that prudent · surface and subsurface drainage practices are incorporated into the construction plans. Perched groundwater conditions along zones of contrasting. permeabilities should not be precludedJrom occurring in the future due to site irrigation, poor drainage conditions, or damaged utilities. Should perched groundwater conditions develop, this office could assess the affected area(s) and provide the appropriate recommendations to mitigate the observed groundwater conditions. Subdrains may be recommended during grading. Mr. David Bentley File:e:\wp7\2900\2929a.lge W.O. 2929-A-SC Page Two GeoSoils, Inc. ·-· •-· •• • The preliminary geotechnical design parameters provided herein should be considered during construction by the project structural engineer and/or architect. The opportunity to be of service is greatly appreciated. If you have any questions concerning this report or if we may be of further assistance, please do not hesitate to contact any of the undersigned. Respectfully submitted, GeoSoils, Inc. Mr. David Bentley File:e:\wp 7\2900\2929a.fge GeoSoils; lne. W.O. 2929-A-SC Page Three •• ,·! TABLE OF CONTENTS .: · SCOPE OF SERVICES ........... : ....................................... 1 ·.·. •:-. SITE DESCRIPTION AND PROPOSED DEVELOPMENT ......... · ................ 1 FIELD EXPLORATION ............................. ; ...................... 3 REGIONAL GEOLOGY ......................... : .. -........................ 3 EARTH MATERIALS .......................•.... : .......................... 4 Topsoil/Colluvium {Not Mapped) ..... : ...................... · .......... 4 Santiago Formation (Map Symbol -Tsa) ................................ 4 Granitics/Santiago Peak Voicanics {Map Syrr:ibols -Kgr/Jsp) ............... 4 GROUNDWATER .............................. , ......................... 5 FAULTING AND REGIONAL SEISMICITY ..... ; ........ · ....................... 5 Seismicity ........................... :·. _ ..................... ~ ..... 7 Seismic Shaking Parameters · ......................................... 8 PRELIMINARY ROCK HARDNESS EVALUATION , ............................. 9 Rock Disposal .•.•........... : ....... .-. . . . .. . . . . . . ..... · . .-. . . . . . . . . . . 9 u\BORA TORY TESTING ...... : .......................................... 10 General ........... · ....•.................... : . . . . . . . . . . . . . . . . . . . . . . 10 Classification . . . . . . . . . . . . . . . . . . . . . . . . . • . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 o Laboratqry Standarq-Maximum Dry Density ................. _ . . . . . . . . . . . 1 o Expansion Potential . . . . . . . . . . . . . . . . . . . .. . . . • . . .. . . . . . . . . . . . . . . . . . . . . . 1 O Atterberg Limits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 o Soluble Sulfates/pH Resistivity· ........ · .............................. 11 CONCLUSIONS AND RECOMMENOATIONS ................................. 11 . General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • . . . . . . . . . . . . ..... : . . . . . . . 11 Earth Materials .................... ·. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Topsoil/Colluvium {No Map Symbol) ............................ 12 Santiago Formation (Map Symbol -Tsa), Granitic Bedrock (Map Symbol - Kgr), and Volcanic/Metavolcanic Bedrock (Map Symbol-Jsp) ... 12 Preliminary Rock Hardness . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Expansion Potential . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Subsurface and Surface Water ...................................... 12 Regjonal Seismic Activity , ............. , . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Slope Considerations and Slope Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 EARTHWORK CONSTRUCTION RECOMMENDATIONS ....................... 14 General ............... · ........................ : ................. 14 Demolition/Grubbing ............................................... 14 Treatment of Existing Ground ............ : .......... · ................ 15 GC?oSoils, lne. ••• •. ,._ .Fill Placement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Overexcavation ... · ................................................. 16 Erosion Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 RECOMMENDATIONS -FOUNDATIONS ...... · .... :-......................... 16 · Bearing Value ............................... · ..................... 17 .Lateral Pressure . . . . . . . . . . . . . . . . . ..... ·. . . • . . . . . . . . . . . . . . . . . . . . . . . . 17 Footing Setbacks ........ ~ ............ ·. . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Construction . . . . . . . . . . . . . . . . . . . . ...... ~ . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Very Low to Low Expansion Potential (Expansion Index o to 50) ........... 18 Medium Expansion Potential (Expansion Index 51 to 9Q) ................. 19 High Expansion Potential (Expansion Index 91 to 130}/Preliminary Post-Tensioned Slab Foundation Systems ..................................... 20 CORROSION ....... : ............................ : ..................... 22 CONVENTIONAL RETAINING WALL RECOMMENDATIONS .. _ .................. 22 Gen·eral . ·. . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . 22 Restrained Walls ................•.................................. 23 Cantilevered Walls ........................•....................... 23 Wall Backfill and Or~inage .......................................... 24 Retaining Wall Footing Transitions ................................... 24 RECOMMENDATIONS-POST EARTHWORK ..... , ........................... 25 Planting and Landscape Maintenance ............................ : ... 25 Additional Site Improvements ......... : ......... ~ ................... 25 · Footing Trench Excavation ........... _ .............................. 25 Drainage .•.... _. . . . . . . . . . . . . . . . . . . . . . . . . • . . . . . . . . . . . . . . . . . . . . . . . . 26 TRENCH BACKFILL ..................................................... 26 PLAN REVIEW . : : ...................................................... 26 INVESTIGATION LIMITATIONS ............................................ 27 FIGURES: Figure 1 -Site Location Map .......................................... 2 Figur~ 2 -California Fault Map ........................................ 6 ATTACHMENTS: . Appendix A-References ................................... Rear of Text Appendix B -Test Pit Logs . , . ~ .............................. Rear of Text Appendix C -Seismic Data .......... , ...................... Rear of Text Appendix D -General Earthwork and Grading Guidelines ......... Rear of Text • Plates 1 and 2 -Geotechnical Maps .................. Rear of Text in Pocket Mr. o·avid Bentley File: e\wp7\29DD\2929a.lge GeoSoils, lne. Table of Contents Page ii •• •• • LIMITED GEOTECHNICAL EVALUATION HOLLY SPRINGS PROJECT CARLSBAD, SAN DIEGO COUNTY, CALIFORNIA SCOPE OF SERVICES The scope of our services has included the following: . . 1. Review of readily . available published literature and maps of the vicinity (Appendix A). 2. Limited subsurface exploration consisting of eleven exploratory test pits to evaluate the existing soil conditions. 3. Limited seismic refraction survey consisting of four seismic lines to evaluate rock hardness .. 4. Limited laboratory testing of tepresentative soil samples collected during our subst:Jrface exploration program. 5. General areal site seismicity and slope stability evaluation . 6. Preparation .of a preliminary geotechnica] report for the subject site that includes seismic evaluation, and recommendations for e,nticipated remedial site grading to mitigate identified geologic hazards. Since detailed development plans (i.e., building locations, building types, etc.) for the site_ are not available at this time, specific foundation design and construction details should be provided as plans become available. SITE DESCRIPTION AND PROPOSED DEVELOPMENT The generally undeveloped property is located in northeastern Carlsbad, north of El Camino Real and the Rancho Carlsbad/Sintorosa Golf Course, and directly w~st of the southwe~terly portion of Leisure Village/Oc~an Hills in Sail Diego, County, California (see Site Location Map, Figure 1). Access to the subject property is via the northern, recently improved extension of Calaveras Drive (north Of Cannon Road and El Camino Real intersection). Overall, the property is covered with what appears to be native vegetation; however, portions of the south-central property (and farmland to the south) are currently . developed for agricultural purposes. A few structures are readily visible in a main compound area, situated within Open Space Lot 58; however, a number of cultivated banana trees currently exist west of the compound, within areas proposed for grading and development. The site is bounded on the north and south by agricultural development mixed with predominantly undeveloped open space areas consisting: of ridges and westerly-flowing GeoSoils, Ine. .. -.. \ Water Tank~- Wair· ·-1an~ ~---- .. - J • i r··· ,·-.. ... : :. \ .:• /' • l'/1 -. ' - .......... ~· ----. ·-·' .. ;._, • "i;;.._, ,-'--1--<· .-.. · -- -.. -- W~e, • 'San ·Francisco · ~ - hn, ·.,Peak·· . __ .-. r .,.... ·---~---:=-.~ .. .,tc· 'I; • <:- 0~ __ ---_::_~·- .-· I ,,·---~,.... Base Map: San Luis Rey Quadrangle, California--San Diego Co., 7.5 Minute Series (Topographic), 1968 (revised 1975), by· USGS, 1":2000' 0 1/2 -a __ i Scale 1 I Miles • N Re.produced with permlaaion granted by Thomaa Stoa. Mapa. Thia map Ii ·copyrighted by Thomas Bro1. Mapa, It is unlawful to copy or reproduce all or any part thereof, whether for personal use or resale, without permission. All rights reserve~, All Locations Are Approximate w.o. 2929-A-SC SITE LOCATION MAP Figure 1 intermittent natural drainages. The eastern edge of the property is bounded by Leisure Village~ A vehicle storage area and agricultural plots associated with a trailer park exist to the west. The south central portion of the property is currently developed for agricultural p_urposes, with farm $Upport structures and an irrigation system, Overall, the site slope$ in a westerly direction toward Calaveras Creek; however, the southern edge of the property slopes in a south to southwest direction. Based upon a 1 DO- scale topographic map/conceptual developmental plan of Holly Springs {by Ladwig Design Group, Inc.), elevations onsite range from ±420 feet Mean Sea Level (MSL) in the eastern area to roughly ± 70 feet MSL in the western area~ At the time of our fie.Id reconnaissance the site in covered predominantly with native grasses and brush. Surface rock outcrops are locally common within the higher elevations of the property. The aforementioned plans for the subject property (by Ladwig Design Group, Inc.) indicates that 1 multi-family lot (Lot 1), 56 single-family lots (Lots 2-57),with 3 open space lots (Lot~ "58, 59, and 60) and interior roadl? are planned for the property. Although construction · plans are · not available, it is likely that residential structures will use continuous. footings and slab-on-grade floors with wood-frame and/or masonry block constructkm. Building loads are assumed to be typical for this type of relatively light structure. The need for import soil (i.e., fill materials) is not known at this time. FIELD EXPLORATION Subsurface conditions were explored for this study by excavating eleven (11) exploratory backhoe test pits to depths ranging from about ±2 to ± 1 O feet below existing grade. Field · work for the t~st pits· was performed on September 19, 2000 by a GSI geologist, who logged the trenches, obtained samples of representative materials for laboratory testing and reviewed the site conditions. Logs of the test pits are presented in Appendix 8. The approximate locations-of exploratory test pits are indicated on the Preliminary Geotechnical . Maps (Plates 1 and?), which utilize a.100-scale developmental map as a base map.· In addition, four (4) seismic refraction lines were conducted on the property to assess the rippability of the bedrock materials. The seismic lines were completed on September 19, 2000 by a GSI staff geologist and field technician. Graphic sections of the four lines, along with interpretations, are provided in Appendix C. The approximate locations are indicated onthe 100-scale Geotechnical Maps (Plates 1 and~). REGIONAL GEOLOGY The site is located in Peninsular Ranges geomorphic province of California. The Peninsular Ranges are characterized by northwest-trending, steep, elongated ranges and valleys. The Peninsular Ranges extend north to the base of the San Gabriel Mountains and Mr.· David Bentiey Holly Springs, Carlsbad File: e\wp7\2900\292_9a.lge W.O. 2929-A-SC October 11, 2000 Page3 ··- • south into Mexico to Baja California. The provinoe is bounded by the east-west trending Transverse Ranges geomorphic province to the north and northeast, by the Colorado Desert geomorphic province to the southeast, and by. the Continental Borderlands geomorphic province to the west. In the Peninsular Ranges, sedimentary and volcanic units discontinu~>Usly mantle the crystalline bedrock, alluvial deposits_ have filled in the lowervalley areas, and young marine sediments a~e currently belng deposited/eroded in the coa~tal,and beach areas. EARTH MATERIALS Earth materials encountered on the site consist of topsoil/colluvium, sediments of the Eocene-age Santiago Formation, granitic bedrock of the southern California Batholith, and volcanic/metavolcanic bedrock of the Jurassic-age ·santiago Peak Volcanics. Mappable units are shown on the Geotechnica:I Maps, Plates 1 and 2. The earth units encountered -are desqribed below, from youngest to oldest. · Topsoil/CoJluvium (Not Mapped) Quaternary-age topsoil/colluvium (i.e., surficial deposits) was observed overlying the site. Topsoil/colluvium, as encountered·onsite, consists of dry, red brown to gray, loose, silty sand with occasionally common gravel, that is compressible. These sediments were encountered typically to a depth of ± 1 to ±3 foot; however, colluvium was encountered to a depth of 5 to 7 feet overlying the Santiago formation in Lot 1. These materials are considered unsuitable for support of settlement sensitive -improvements in their existing condition. · Santiago Formation (Map Symbol _-Tsa) Underlying the surficial deposits in the extreme westerly portion of the property is a formational unit, consisting of sediments-belonging to the Eocene-age Santiago Formation. These sediments, as encountered onsite, consist of moist, medium dense, yellow-brown sandstones with interbedded siltstone and claystone beds: These materials are considered suitable for support of settlement sensitive improvements, provided the upper weathered portion of the unit ·is removed ~nd/or reprocessed. Granitics/Santiago .Peak Volcanics (Map Symbols -Kgr/Jsp) Underlying the property as a whole, as well as exposed locally at the surface in the form of outcrops, are intrusions of granitic bedrock of the Cretaceous-age southern California Batholith (Kgr) into volcanic/metavolcanic bedrock of the Jurassic~age Santiago Peak Volcanics. Where encountered onsite, there materials consisted of brown to gray to red brown, dense to very dense and hard bedrock that typically excavateo to silty sands and silty sandy gravels. Although this material was found to be decomposed and massive, Mr. David Bentley Holly Springs, Carlsbad. File: e\wp7\2900\2929a.lge GeoSoils, Inc. W.0. 2929-A-SC October 11 , 2000 Page4 • •• •• practical refusal was achieved ·at depths between 3½ and 7 feet. Difficult excavation operations should be anticipated below a depth of +5 feet with conventional grading equipme.nt, or from the surface where rock outcrops exist. The· need for blasting to achieve design grade(s) may not be precluded, and should be anticipated. This bedrock is considered suitable for support of settlement sensitive improvements, provided the upper weathered portion of this unit is removed and/or reprocessed. GROUNDWATER Sub$urface water was not encountered in any of the excavations completed during this study. Subsurface water is hot anticipated to adversely affect site development, provided that tbe recommendations contained in this report are incorporated into final design and construction, and that prudent surface and subsurf~ce drainage practices are incorporated into the construction plaris. _ These observations reflect site conditions at the time of our investigation and do not preclude future cbanges in .local groundwater conditions from excessive irrigation, precipitation, or that were not obvious, at the time of our investigation. Seeps, springs, or other indications of a high groundwater level were not noted on the subject property .during the time of our field investigation. However, seepage may occur locally (due to heavy precipitation or irrigation) in areas where fill soils overlie silty or clayey soils .. Such soils may be encountered in the earth units that exist onsite . . ' ' ' Perched groundwater conditions along fill/bedrock contacts and along zones of contrasting permeabilities should not be precluded from occurring in the future due to site irrigation, .. poor drainage conditions, or damaged utilities. Should perched groundwater conditions _develop, this office _could assess the affected area(s) and provide the appropriate recommendations to mitigate the observed groundwater conditions. Subdrains may be recommended during grading based on the conditions exposed. -FAULTING AND REGIONAL SEISMICITV The site is situated in an area of active as well as potentially-active faults. Our review indicates that there are no known active faults crossing the site within the areas proposed for development (Jennings, 1994), and the site is not within an Earthquake Fault Zone (Hart and Bryant, 1997). · No evidence of faulting was encountered in our subsurface investigation. There are a number of faults in the southern California qrea which are considered active and would have an effect-on the site in the form of ground shaking, should they be the sourc.e of an earthquake. These include, but are not limited to: the San Andreas fault, the San Jacinto fault, the Elsinore fault, the Coronado ·sank fault zone and the Rose Canyon - Newport-Inglewood (RCNI) fault zone. The approximate location of these and other major Mr. David Bentley Holly Springs, Carlsbad File: e\wp7\2900\~929a.lge GeoSoils, lne. W.O. 2929-A-SC October 11, 2000 Pages •• ••• •• \ ~ "\ I SAN FRANCISCO SITE LOCATION (+): ------------ Latitude ·-33.1530 N Longitude -117 .2810 W HO_LLY SPRINGS W.0. 2929-A-SC CALIFORNIA 0 50 100 SCALE (Miles) Figure 2 •• faults relative to the site are presented in Figure 2. The possibility of ground acceleration, or shaking, .at the site may be considered as approximately similar to the southern . California region as a whole. · The acceleration-attenuation relations of Idriss (1994), and Campbell and Bozorgnia (1994) have ·been incorporated into EQFAULT (Blake, 1997). EQFAULT is a computer program used for the deterministic evaluation of horizontal accelerations from digitized California faults. The following table lists the major faults and fault zones in southern California that could have a significant effect on the site should they experience significant activity. ABBREVIATED FAULT NAME 1· APPROXIMATE DISTANCE. MILES (KM) I Coronado Bank-A ua Blanca _ 23 37.0 Elsinore 22 35.4) La Nacion 23 37.0 H 17.7) Rose Can on 711.3 33 53.1 Seismicity The acceleration-attenuation relations of Idriss {1994) and Campbell and Bozorgnia (1994) have been incorporated into EQFAU~T (Blake, 1997). For this study, peak horizontal ground accelerations anticipated at the site were determined based oh the random mean attenuation curves developed by Idriss (1994) and Campbell and Bozorgnia (1994). These acceleration-attenuation relations have been incorporated in EQFAULT, a comp·uter program by Thomas F. Blake (1997), which performs deterministic seismic h~ard analyses using up to 150 digitized California faults as earthquake sourc~s. The program estimates the closest distance between each fault and a user-specified file. If.a fault is found to be within a user-selected radius, the program estimates peak horizontal ground acceleration that may occur at the site from the "upper bound" (maximum credible) and "maximum probable" earthquakes on that fault. Site acceleration (g) is computed by any of the 14 user-selected acceleratiqn-attenuation relations that are containeq in EQFAULT. Based on the above, peak horizontal ground accelerations from an upper bound event may be on tbe order of 0.451 g to 0.493 g, and a maximum probable event may be on the order of 0.246 g to 0.262 g, assuming an upper bound (maximum credible) Mr. David Bentley Holly Springs, Carlsbad File: e\wp7\2900\2929a.lge Gef)SOil$, Ine. W;O. 2929-A-SC October 11, 2000 Page7 • • and.maximum probable event of magnitude about 6:9, on the Rose Canyon fault zone, located approximately 7 miles-west from the subject site. Seismic Shaking Parameters Based on the site conditions, Chapter 16 of the Uniform Building Code (International Conference of Building Officials, 1-997) and Petersor:i ·and others (1996), the following seismic parameters are provided. - Seismic zone (per Figure 16-2*) 4 Seismic Zone Factor (per Table 16-1*) 0.40 Soil Profile Type (per Table 1 S-:J*) Sa**, S/**, S0 **** Seismic Coefficient c. (per Table 16-Q*) .. 0.40N. Seismic Coefficient Cy (per"Table 16-R*) 0.56 Ny Near Source Factor N. (per Table 16-S*) 1.0 . Near Source Factor Ny (per Table 16-T*) 1.2 Seismic Sourc~ Type (per Table 16-U*) B Distance to Seismic Source 7 mi. (11.2 km) Upper Bound Earthquake Mw6.9 * Figure and table references from Chapter 16 of the Uniform Building Code (1997). ** Sa may be used for lots underlai'n by bedrock (Granitics/Santiago Peak. Volcanics) *** Sc may be µsed for lots by bedrock (Granitics/Santiago Peak Volcanics), where fills are more than 1 O feet below the bottom of the footings. **** S0 may be used for lots underlain by formational sediments (Santiago Formation), or for lots where fills have been placed on formational sediments. It should be noted that the parameters above are provided for the ·average soil properties for the top 100 feet of the soil profile. The S8 parameters are reasonably and conservatively justified for competent rock with moderate fracturing and weathering based ·on an estimated shear wave veiocity (a "S" wave) of greater than 2,500 feet per second (fps) in the top 100 feet of the soil profile, as contrasted to_ the velocities used in our seismic refraction-studies (a "P" wave). The estimate S wave velocities are about 0.58 of P wave velocities measured in our seismic refractions studies (Das, 1992; Hunt, 1986; and · Griffiths and King, 1976). Accordingly, in accordance with the 1997 USC, it is reasonably estimated that the shear wave velocity for the average soil profile of the top 100 feet of the soil pro~le exceeds 2,500 fps in granitic/Volcanic bedrock . Mr. David Bentley Holly Springs, Carlsbad File: e\wp7\2900\2929a.lge GeoSoils, Inc. W.O. 2929-A-SC October 11, 2000 Page a • • • PRELIMINARY ROCK HARDNESS EVALUATION A limited subsurface investigation, consisting of 4 seismic refraction survey lines was performed to assess the rippability of the bedrock materials. The results of the limited seismic refraction survey are provided in Appendix C. The locations of the seismic lin'es are shown on the Preliminary Geotechnical Maps, Plates 1 and 2. For the purposes of this discussion, approximate cut-off seismic velocities of 6000 feet per second were used as a basis for non-rippable bedrbck. Approximate cut-off seismic velocities of ~800 feet per second should be used as a basis for non-rippable trenchin_g. Rfppability of bedrock within the proposed grading limits is expected to be highly variable. Generally, excavations will likely require blasting below depths of ± 15 to ±30 feet. Sedrock appears to be rippable with heavy grading equipment at shallower depths; -however, in these "rippable" areas, surface rock outcrops, hard layers, and floaters (isolated hard zones and/or boulders) will be encountered that will be difficult to excavate with conventional grading equipment, and may require blasting. A more detailed rock hardness ·evaluation is recommended as 401-scale grading plans become available. Rock Disposal The bulk of the materials derived from the weathered ·portion of the bedrock (up to and including the 3000-4500+ fps cut-off) are anticipated to disintegrate to approximately 12- to 24-inch diameters and smaller. Fills should be Well-graded mixtures of fines with rocK no larger than 1-2 inches in diameter. Rocks larger than 12 inches will require special handling for use in fills. Typically, oversized rocks are placecl in -rock blankets, rock windrows; and/or pits for _individual rocks. The major constraints to rock disposal on the -subject site are Jhe limited areas suitable for rock. disposal and the availability of fines required for filling rock fill voids. Oversized rock should be held below the range of foundations, utilities, or other underground excavations to facilitate trenching, and held at least 15± _feet away from slope faces; so as not to adversely affect slope stability. For preliminary planning ·purposes, it can be assumed at least 50% of materials excavated will generate oversized rock (i.e., 12 inches or greater) requiring special handling. Hqwever, such an estimate should be used with caution, and not without consulting a grading contractor experienced with residential development in hard rock terranes . Mr. David B~ntley Holly Springs, Carlsbad File: e\wp7\2900\2929a.lge GeoSoils, lne. W.0. 2929-A-SC October 11, 2000 Page9 • •••• •· .. : .. LABORATORY TESTING General Laboratory tests were performed on representative samples of the onsite earth materials in order to evaluate their physicat· characteristics. Test procedures used and results obtained are presented below. Classification Soils were classified visually according to the Unified Soils Classification System. The soil classifications are shown on the test pit logs in Appendix B. Laboratory Standard-Maximum Dry Density To determine the compaction characteristics of tepresentative samples of onsite soil, laboratory testing was performed in accordance with ASTM test method D-1557. Test results are presented in the following table: I·,,.,,_;· __ _.: LOCATION .. ~, .. :.~.,-·.-f .. ·:: MAXIMUM tjENSITY (pcff '·: I OP"I:IMUM MOISTURE CONTENT(%) I . I TP-:2@ 0-1' I 129.0 I 10.0 I Expansion Potential Expansion index tests were performed on a r~presentative sample of site soil in general accordance with Standard 18-2 of the Uniform Building Code. Results are presented in the following table.· I ·;('.:; · t.:oc.Ar1or·,t--~·::.<:.-1. -, .. :::--,<~01L TYPE: /;fi~~::, ··I-. ~xPANs19N _ 1N0Ex · I 1:xPANs10N PorENTIAL. I I TP-2 @ 0-1' I Brown, silty SAND I <S . I Very Low I Atterberg Umits To help determine the consistency and plasticity of fine grained soils on the site, a selective sample was chosen and tested for their Atterberg Limits. Testing was completed pursuant to post-tensioned foundation design requirements presented in the 19Q7 Uniform Building Code (UBC). The testing was performed in acc0rdance with ASTM Test Method D-4318. The results are presented in the following table: Mr. David Bentley Holly Springs, Carlsbad File: e\wp7\2900\2929a.lge GeoSoils, Inc. W.O. 2929-A-SC October 11 , 2000 Page 10 ... :. • I SAMPLE LOCATION LIQUID LIMIT . I PLASTICITY INDEX I · TP-2@ 0-1' Nori Plastic I Non Plastic .Soluble Sulfates/pH Resistivity A sample of the thicker colluvial materials were analyzed for soluble sulfate content _and corrosion to ferrous metals. The results are as follows: LOCATION ! SOLUBLE SULFATES (mg/kg)° I pH I RESISTIVITY-SATURATED (ohms-cm) I TP-10@ 5-7' I 50 I 7.0 I 780 I _CONCLUSIONS AND RECOMMENDATIONS General Based on our field exploration, laboratory testing and geotechnical engineering analysis, it is our opinion that the . site appears suitable for the proposed development from a geotechnical engineering and geologic viewpoint, provided that the recommendations presented in the following sections are incorporated into the design and construction phases of site development. · The p·rimary geotechnical concerns' with respect to the proposed development are: • Earth materials characteristics and depth to competent bearing material. • Expansion and corrosion potential of site soils. • Potential for drill and shoot/blasting. • Regional seismic activity. • Subsurface water and potential for perched water. lhe re·commendations presented herein consider these as well as other aspects of the site. In the .event that any significant changes are made to ptoposed site development, the conclusions and recommendations contained in this report shall not be considered valid unless the changes are reviewed and the recommendations of this report verified or modifiec;:I in writing by this office. Additional subsurface studies, including rock hardness evaluation, are recommended as more· detailed plans are available. Foundation design parameters are considered preliminary until the foundation design, layout, and structural loads are provided to this office for review . Mr. David Bentley Holly Springs, Carlsbad File: e\wp7\2900\2929a.lge GeoSoil$, Inc. W.O. 2929-A-SC October 11, 2000 Page 11 ···:·.· e:. •. : Earth Materials Tops()il/Colluvium (N.o Map Symbol) Topsoil/colluvial materials are generally moist and loose and/or do not meet the current industry minimum standard of 90 percent {Or greater) relative compaction, Recommendations for the treatment of topsoil/colluvium are presented in the earthwork section of this report. · . Santiago Formation: (Map Symbol -Tsa), Granitic Bedrock (Map Symbol -Kgr), and Volcanic/Metavolcanic Bedrock (Map Symbol-Jsp) Formational and bedrock materials will be encountered during site earthwork. These materials are considered competent to support settlement-sensitive structures ·in their existing state, provided the upper highly weathered portions are reprocessed and moisture conditioned. The Santiago Formation should be .excavated with conventional heavy grading equipment. Difficulty should be anticipated below. a depth of ±5 feet where granitic and/or volcanic/metavolcanic bedrock is encountered. The need for blasting may not be precluded, and should be locally anticipated. Preliminary Rock Hardness The results of the seismic refraction survey suggested dense to very dense, non-rippable bedrock materials exist at a depth, locally, of ±t5 to ±30 feet. The rippability of the bedrock within the proposed grading limits is expected to be highly variable: For budgetary purposes, however, surface rock outcrops, .hard layers, and floaters (isolated hard zones arid/or boulders) will likely be encountered that will be difficult to excavate with conventional grading equipment, and may require blasting. Expansion Potential Based upon our exp~rience in the area, as well as upon review of laboratory test results indicate that s.oils with a very low to possibly high expansion potential underlie the site. Field observations· of the siltstone and claystone interbeds of the Santiago formation suggest that they may have a medium to high expansion potential. This should be considered during project design. Foundation design arid construction recommendations are providec;:J herein for very low to high expansion potential classifications. Subsurface and Surface Water Subsurface and surface waters, as discussed previously, are not anticipated to affect site development, provided that the recommendations contained. in this report are incorporated into final design and construction, and that prudent surface and subsurface drainage practices are incorporated into the construction piari$ . Mr. David Bentley Holly Springs, Carlsbad File: e\wp7\2900\2929a.lge GeoSoils, Itae. W.O. 2929-A-SC October 11, 2000 Page 12 • Perched groundwater conditions along fill/formational contacts and along zones of contrasting permeabilities should not be pre~luded from occurring in the future due to site irrigation,. poor drainage conditions, or· damaged .utilities. Should perched groundwater qonditions develop, this office could assess the affected area(s) and provide the appropriate recommendations to mitigate t~e observed groundwater conditions. Subdrains may be recommended during grading. The groundwater conditions observed and opinions generated were those at the time of our investigation. Conditions may change with the introduction of irrigation, rainfall, or other factors that were not obvious at the time .of our investigation. ReQional Seismic Activity The seismic acceleration values provided herein should be considered during the design of the proposed development. Slope Considerations and Slope Design Alf . slopes should be designed and · constructed in accordance with the minimum requirements of the City of Carlsbad, the recommendations in Appendix D, and the following: . 1. 2. 3. Fill slopes should be designed and qonstructed at a 2~ 1 (~orizontal to vertical) gradient or flatter, and should not exceed 20 feet ih height without additional slope stability analysis. Fill slopes should be properly built and compacted to a minimum relative .compaction of 90 percent throughout, including the· slope surfaces. Guidelin~s for slope construction are presented in Appendix D. Cut slopes should be designed at gradients of 2:1 (horizontal to vertical), and should not exceed 1 0 feet in height without additional slope stability analysis .. While stabilization of such slopes is not anticipated, locally adverse geologic conditions (i.e., daylighted joints/fractures or severely weathered bedrock) may be encountered which may require remedial grading or laying back of the slope to an angle flatter than the adverse geologic condition. Based upon the information collected as a part of this study, there are no graded slopes that require buttressing; however, based on the impermeability (i.e., seepage potential) and high expansion potential encountered locally in the clayey topsoil/colluvial ~oils and siltstone/claystone bedrock, cut slopes associated with Lot ~ (multi-fami_ly lot) may requite a stabilization fill with backdrains. Local areas of highly weathered bedrock may also be present within the· property as a whole. Should these materiais be exposed in cut slopes, the potential for long term maintenance or possible slope failu·re exists. Evaluation of cut slopes during Mr. David Bentley Holly Springs, Carlsbad File: e\wp7\2900\2929a.lge W.O. 2929-A-SC October 11, 2000 Page 13 GeoSoils, Ine. e: •. < • ::· ... 4. grading wouid be necessary in order to· identify any areas of severely weathered rock or non-cohesive sands. Should any of these materials be exposed during construction, the soils engineer/geologist, would assess the magnitude and extent of the materials and their potential affect on long-term maintenance or possible . ) . slope failures. Recommendations would then be made at the time of the field inspection: Further evaluation of slope stability should be conducted at the 40-scale grading-plan stage. Cut slopes should be mapped by the project engineering -geologist during grading to allow amendments to the recommendations should exposed conditions warrant alternation of the design or stabilization.· EARTHWORK CONSTRUCTION RECOMMENDATIONS General 1. Soils · engineering and compaction testing services should be provided during ·grading operations to assist the contractor in removing unsuitable soils and in his effort to compact the fill. 2. Geologic observations should be performed during.grading to verify and/or further evaluate geologic conditions. Although unlikely, if adverse geologic structures are encountered, supplemental recommendations and earthwork may be warranted. . . 3. In general and based upon the available data to· date, groundwater is nor expected to be a major factor in development of the site. However, due to the nature of the site materials, local seasonal seepage may be encountered throughout the site along with s~asonal perched water within ariy drainage areas. 4. Current local and state/federal' safety ordinances for subsurface trenching should be enforced.- 5. General Earthwork and Grading Guidelines are provided at the end of this report as Appendix D. Specific recommendatiohs are-provided below.· Demolition/Grubbing 1 . Any existing subsurface structures, major vegetation, and any miscellaneous debris . should be removed from the areas of proposed grading . Mr. David Bentley Holly Springs, Carisbad File: e\wp7\2900\2929a.lge Ge.oSoils, lne. W.O. 2929-A-SC October 11, 2~00 Page 14 • •. :,:_ .. ••• 2 . The project soils engineer should be notified of any previous foundation, irrigation lines, cesspools, or other subsurface structures-that are uncovered during the recommended removals, so that appropriate remedial recommendations can be provided. · · Treatment of Existing Ground 1. Existing vegetation and/or deleterious trash and debris should be stripped and hauled offsite in the areas of proposed development. 2. Removals/reprocessing in areas planned for settlement-sensitive improvements (including pavement areas) shall consist of all topsoil/colluvium, existing fill materials (if any), and alluvium. These materials should be removed, moisture conditioned ·to at least optimum · moisture content, and rec6rripacted and/or processed in place to a minimum relative compaction of 90 percent of the laboratory standard (ASTM D-1557). These conditions should be tested by a representative of our firm. 3. Topsoil/colluvium, existing fill (if any), arid alluvium may be reused as compacted fill provided that major concentrations of vegetation and miscellaneous debris are removed prior to or during fill placement. Fill Placement 1. Fill materials should be brought to at least. optimum moisture, placed in thin 6-to · .. 8-inch lifts and mechanically c9mpacted to obtain a minimum relative co_mpaction of 90 percent of the laboratory. standard. 2. Fill materials should be cl1?ahsed of major vegetation and debris prior to placement. 3. Any oversized rock materials greater than 12 inches in diameter should not be placed within the upper 3 feet of the proposed foundation, and the upper 12 inches offinisf-1 grade materials on pads· should consist of 6 inch and minus earth materials. 4. Any import materials should be observed and determihed suitable by the soils engineer prior to placement on the site. Foundation designs. may be altered if · import materials have a greater expansion value than the onsite materials encountered in this investigation. 5. Should significant amounts ·of rock be generated, recommendations for rock fills can be provided . Mr. David Bentley Holly Springs, Carlsbad File: e\wp7\2900\2929a.lge GeoSoils, Ine. W.0. 2929-A-SC October 11, 2000 Page 15 •• •• •• Overexcavation Proposed grading of the building sites may create a cut/fill transition in the building pad · · area where bedrock is juxtaposed against proposed fill. In such areas, the bedrock should be overexcavated to a depth of 3 feet, or the minimu~ depth as defined within the removals section· presented above, whichever is greater. Overexcavation should be completed for a minimum lateral distance of 5 feet outsid~ the extreme foundation elements, or a 1 :1 projection from the bottom of the footing, whichever is greater. If footing embedments are greater than 24 inches, the overexcavation should be increased to a minimum of 2 feet below the bottom of the footing. Based on the conditions disclosed during. grading, overexcavation .and .laying back of subsurface slopes to an inclination of 3:1 (h:v) or flatter may be required. If the foundation envelopes (i.e., building footprints) are not fi'nalized as of the date of grading, the entire lot should be overexcavated. Consideration may be given to overexcavation of hatd-rock areas to facilitate utility construction in street areas, and/or foundation excavation. This is not a geotechnical requirement, but should also be considered. · Erosion Control Onsite soils and/or formational materials have a moderate erosion potential. Use of hay bales, silt fences, and/or sandbags should be considered, as appropriate. Temporary grades should be constructed to cirain at 1 to 2 perc·ent to a suitable temporary or permanent outlet. Evaluation of cuts during grading will be necessary in order to identify any areas of loose or non-cohesive material$. · Should any significant zones be encountered during earthwork construction remedial grading may be recommended; however no remedial measures are anticipated at this time. RECOMMENDATIONS -FOUNDATIONS In the event that the information concerning the proposed development plan (by Ladwig Design Group) is not correct or any changes in the design, location, or loading conditions of the proposed structures are made, the conclusions and recommendations contained in this report are for the subject site only and shall not 'be considered valid -unless the changes are reviewed and conclusions of this report are modified or approved in writing by this office. The information and recommendations presented in this section are considered minimums and are not meant to supersede design(s) by the project structural engineer or civil engineer-specializing in structural design. Upon. request, -GSI cou/d provide additional consultation regarding soil parameters, as related to foundation design. They are considered preliminary recommendations for proposed construction, in consideration of our field investigation, and laboratory testing and engfneer:ing analysis . Mr. David Bentley Holly Springs, Carlsbad File: e\wp7\2900\2929a.lge GeoSoils, Ine. W.O. 2929-A-SC October 11, 2000 Page 16 e:.'_ Our review, field work, and laboratory testing indicates that onsite soils have a very low (expansion index Oto 20) to high expansion potential range (expansion index 91 to 130). - Preliminaryrecommendationsforfoundation design and construction are presented below. Final foundation recommendations should be provided at the conclusion of grading based o·n laboratory !esting of fill materials exposed at finish grade; Bearing Value 1. The foundation systems .should be designed and constructed in accordance with guidelines presented in·the latest edition of the Uniform Suilding Code. 2. An allowable bearing value of1 ,500 pounds per square foot may be used for design of continuous footings 12· inches wide and 18 inches deep· and for design of isolated pad footings-24 inches square and 24 inches deep founded entirely into compacted fill. or competent formational material and connected by grade beam or tie beam in at least one direction. This value may be increased by 20 percent for each additional 12 inches in depth to a maximum value of 2,500 pounds per square foot. The above values may·be increased by one;.third When considering short duration seismic or wind loads. No increase in bearing for footing width is recommended. Lateral Pressure 1. For lateral'.sliding resistance, a 0.35 coefficient of friction may be utilized for a concrete to soil contact when multiplied by the dead load. 2. Passive earth pressure may be computed as an equivalent fluid having a density of 250 pounds per cubic foot with a maximum earth pressure of 2,500 pounds-per square foot 3. When combining passive pressure and frictional resistance, the passive pressure component should be reduced by one-third. Footing Setbacks All footings should maintain a minimum 7-foot horizontal setback from the base of the footing to any descending slope. This distance is measured from the footing face at the bearing elevation. Footings should maintain a minimum horizontal setback ·of H/3 (H =slope height) from the base of the footing to the descending slope face and no less than 7 feet nor need to.be greater than 40 feet. Footings adjacent to unlined drainage swales should be deepened to a minimum of 6 inches bslow the invert of the adjacent unlined swale. Footings for structures adjacent to retaining walls should be deepened so as to extend below a 1 :1 projection from the heel of the wall. Alternatively, walls may be· Mr. David Bentley Holly Springs, Carlsbad File: e\wp7\2900\2929a.lge OeoSoils, Inc. W.O. 2929-A-SC October 11, 2000 Page17 •. -:. • ·:-:-::: .. designed to accommodate structural loads from buildings or appurtenances as described in the retaining wall section of this report. Construction The following foundation construction recommendations are presented as a minimum criteria from a soils engineering standpoint. The onsite soils expansion potentials are generally in the very low range (expansion index o to 20); however, bedrock rnaterials from the Santiago formation may range up to the high (expansion index 91 to 130) range. Recommendations for very low to high ex·pansive soils, therefore, are presented herein for your convenience. · Recomm~ndations by the project's design-structural· engineer or architect, which may exceed the soils engineer's-recommendations, should take precedence over the following minimum requirements. Final foundation design will be provided based on the expansion potential of the near surface soils enqoU_ntered during grading. Very Low to Low Expansion Potential (Expansion Index o to 50) 1. 2. Exterior and interior footings should be founded at a minimum depth of 12 inches for one-story floor loads, ana 18 inches below the lowest adjacent ground surface for two-story floor loads·. All footings should be reinforced with two No. 4 reinforcing bars, one placed near the top and one placed near the bottom of the footing . Footing widths should be as indicated in the Uniform Building Code (International Conference of Building Officials, 1997). A grade beam, reinforced as above, and at least12 inches wide should be provided across large (e.g. doorways} entrances. The base ·of the grade beam should be at the same elevation as the bottom of adjoi!ling footings. 3. -Residential concrete slabs, where moisture condensation is undesirable, should be underlain with a vapor barrier consisting of a minimum of 6 mil polyvinyl chloride or equivalent membrane with all laps sealed. This membrane should be covered above· and below with_ a minimum of 2 inches of sand (total of 4 inches) to aid in uniform curing of the concrete and to protect the membrane from puncture. 4. Residential concrete slabs should be a minimum of 4 inches thick, and should be reinforced with No. 3 reinforcing bar at 18 inches on center in both directions, or 6x6 -W1 .4 x W1 .4 welded wire mesh. If welded wire mesh is selected, No. 3 reinforcing bar at 18 inches on center should be doweled between the exterior footing and 3 feet into the slab. All slab reinforcement should be supported to ensure placement near the vertical midpoint of the concrete. 11Hooking11 the wire mesh is not considered an acc.eptable method of positioning the reinforcement. Mr. David Bentley Holly Springs, Carlsbad File: e\wp7\29DD\2929a.lge GeoSoils, Ine. W.O. 2929-A-SC Octot>er 11, 2000 Page 18 . i I • 5. Residential garage slabs should be reinforced as above and poured separately from the structural footings and quartered with ·expansion joints or saw cuts. A positive separation from the footings should be maintained with expansion joint material to permit relative movement. 6. Presaturation is not required for these soil conditions. The moisture content of the subgrade soils should be equal to or greater than optimum moisture content in the slab areas. Prior to placing visqueen or reinforcement, soil moisture content should be verified by this office within 72 hours of pouring slabs. Medium Expansion Potential (Expansion Index 51 to 90) 1. Exterior and interior footings should be fouhded at a minimum depth of 18 inches for one-story loads, and 24 inches below the lowest adjacent ground surface for twb-stoty loads. All footings should be reinforced with two No. 4 reinforcing bars, orie placed near the top and one placed near the bottom of the footing. Footing widths should be as indicated in. the Uniform Building Code (International . Conference of Building Officials, 1997). 2. A grade beam, reinforced as above, and at least 12 inches wide should be provided across large (e.g. doorways) entrances. The base.of th~ grade beam should be at the same elevation as the bottom ·of adjoining footings. 3. Concrete slabs, where moisture condensation is undesirable, should be underlain with a vapor barrier consisting of a minimum of 6 mil polyvinyl chloride or equivalent membrane with all laps sealed. This membrane should be covered above and below with a minimum of 2 inches· of sand (total of 4 inches) to aid in uniform curing of the concrete and to protect the membrane from puncture. 4. Concrete slabs should be a minimum of 4 inches thick, and should be minimally reinforced with a No. 3 reinforcing bar at 18 inches on center. A No. 3 reinforcing bar at 18 ihches on c·enter should be dowel.ad between the exterior footing and 3 feet into the slab. -All slab reinforcement should be supported to ensure placement near the vertical midpoint of the concrete. 11Hooking11 the' wire mesh is not considered an acceptable method c;>f positioning the reinforcement. 5. Garage slabs should be reinforced as above and poured separately from the structural footings and quartered with expansion joints or saw cuts. A positive separation from the footings should be maintained with expansion joint material to permit relative movement. 6. Presaturation is recommended for these soil conditions. The moisture content of the subgrade soils should be equal to or greater than 120 percent of optimum moisture content to a depth of 18 inches below grade in the slab areas. Prior to Mr. David Bentley Holly Springs, Carlsbad File: e\wp7\2900\2929a.lge GeoSoils, Ine. W.O. 2929-A-SC · October 11, 2000 Page 19 • •• • placing, visqueen or reinforcement, soil presaturation should be verified by this office within 72 hours of pouring slabs·. High Expansion Potential (Expansion Index 91 to 130)/Preliminary Post-Tensioned ~lab Foundation Systems Post.atensioned (PT) slabs may be utiliied for construction of typical one-and two-story residential structures onsite. PT slabs are required for an .expansion potential of 9·1 or greater .. The information and recommendations provided herein are not meant to supersede design by a registered structural engineer or civil engineer familiar with PT slab design. From a so_il expansion/shrinkage standpoint, a fairly common contributing factor to distress of structures using post-tensioned slabs is· a significant fluctuation in the moisture content of soils underlying the perimeter of the slab, compared to the center, causing a "dishing" or 11arcl:iing11 of the slabs. To mitigate this possible phenomenon, a combination of soil presaturation (if necessary, or after the. project has been dormant for a period of time), and/or construction. of a perimeter "cut off' wall grade beam should be employed. For high -(El 91 to 130) expansive soils, perimeter and mid-span beams should be a minimum of 24 inches deep below lowest adjacent pad grade. The perimeter foundations may be integrated into the slab design or independent of the slab. The perimeter beams should be a minimum of 12 inches in width. In moisture sensitive slab areas, a vapor barrier should be utilized and be of sufficient thickness to provide an adequate separation of foundation from soils (6 mils thick). The vapor barrier should be lapped and sealed to provide a continuous water-resistant barrier under the entire slab. The vapor barrier shou.ld be sandwiched between two 2-inch thicK layers of sand (SE>30}. Specific soil presaturation for slabs is required for high to very· tiigh expansive soils; however, the moisture content of the subgrade soils should be at or above the soils optimum moisture content to a minimum depth of 24 inches below grade depending on the footing embedment. Post-tensioned slabs should be designed using sound engineering practice and be in accordance with the Post-Tensioned Institute (PTl).local and/or national code criteria and the recommendations of. a structural ot civil engineer qualified in a post-tensioned slab design. Alternatives to Pfl methodology may be used if equivalent systems can be proposed which accommodate the angular distortions, expansion parameters, and settlements noted for this project. If alternatives to PTI are suggested by the structural consultant, consideration should be given for additional review by qualified structural PT designer . Mr. David Bentley Holly Springs, Carlsbad . -File: e\wp7\2900\2929a.lge GeoSoils, Jne. W.O. 2929-A-SC October 11, 2000 Page 20 • ., •• Perimeter Footing Embedment* ,24" Percent Clay 40% Percent Passing #200 Sieve '85% Allowable_ Bearing Value 1000 psf* Modulus· of Subgrade Reaction 75 psi/inch Coefficient of Friction Q.30 Pa~sive-Pressure 225 * Internal bearing value within the perimeter.of the Post-Tensioned slab may be increased by 20% (200 .psf) for each foot of ~mbedment (beyond 611 surface subgrade) to a maximum value of 2000 psf. The following table presents suggested minimum coefficients to be used in the Post- Tensioning Institute design meth(?d: · 1 · -' .. ' 'i,-~ .:·. : • ' DESIGN METHOD . I MINIMUM COEFFICIENT TO BE U~ED I Thornthwaite Moisture Index -20 inches/year Correction Factor for Irrigation 20 Inches/year Depth to Constant Soil Suction , . 5 (feet) Constant Soil Suction (pf) 3.6 Based on the c1bove parameters, the following values were obtained from figures or tables of the Uniform Building Code (1997). The values may not be appro'priate to account for possible differential settlement of the slab due to other factors. If a stiffer slab is desired, - higher valt;Jes of Ym may ,be warranted. em center lift .. em edge lift Ym center lift Ym edae lift Mr. David Bentley · Holly Springs, Carlsbad. File: e\wp7\2900\2929a.lge 5.0 feet · 2.5 feet 1.10 inches 0.35 inches 5.5 feet 5.5 feet 2.1 feet 3.0 feet 2.0 inches· 2.5 inches. 0.5 inches 0.75 inc.hes GeoSoils, Inc. 5.5 feet 3.0 feet 4.0 inches 1.5 inches W.O. 2929-A-SC October 11, 2000 Page 21 •:·: ·-· -· •·:_._ :=· Perimeter grade beams should .be incorporated into the design and should be a minirriu·m of 24 inches deep. Midspan beams (24 inches embedment) should be incorporated into the design of the post-tensioned slabs. · · ·CORROSION Limited laboratory testing for soluble sulfates, pH,· and corrosion to metals have .been completed. Preliminary laboratory test results indicate that-site materials have a negligible poten~ial for corrosion to concrete (i.e., sulfate content) and a severely high potential_ for corrosion to exposed ste.el (i.e., saturated resistivity). Specific test results were previously. provided in the Laboratory section of this report. Upon completion of grading, additional testing of soils (including import materials) i~ recommended prior to the construction of utilities and foundations·. Further evaluation by a qualified corrosion engineer may be considered.-Accordingly, the use of Type V concrete with a modified water/cement ratio cannot be precluded. CONVENTIONAL RETAINING WALL RECOMMENDATIONS General The equivalent fluid pressure parameters provide for the use of very low expansive select granular backfill to be utilized behind the proposed walls. The_ low ·expansive granular backfill, should be provided behind the wall at a 1 :1 (h:v) projection from the heel of the foundation system. Low expansive fill is Class 3 aggregate baserock or Class 2 permeable rock or suitable site soils-tested to oe in the very low expansion range during backfilling. · Wall backfilling should be performed with_relatively light equipment within the sanie 1 :1 projection (i.e., hand tampers, walk behihd compactors)., Expansive soils should not be used to backfill any proposed walls. During construction, materials should not be stockpiled behind nor in front of walls for a distance of 2H where H is the height of the wall. Foundation systems for any proposed retaining walls should be-designed in accordance with the recommendations presented in the Foundation Design section of this report. There should be no increase in bearing for footing width. Building walls, below grade, . should be Water-proofed or damp-proofed, depending on the degree of moisture protection desired. All walls should be properly designed in accordance with the recommendations presented below. Additional geotechnical design parameters will be required for specialty Walls (i.e., Keystone, Leffel, Crib, Geogrid, etc.), and will be provided upon request, based on their proposed evaluation and use. · Some movement of the walls constructed should be anticipated as soil strength parameters are mobilized. This movement could cause some cracking depending upon the materials used to construct the wall. To reduce the potential for wall cracking, walls Mr. David Bentley Holly Springs, Carlsbad File: e\wp7\2900\2929a.lge GeoSoil$, Ine. W.O. 2929-A-SC October 11, 2000 Page 22 •• •. _: •• should be internally grouted and reinforced with steel. To mitigate this effect, the use of vertical crack control joints and expansion joints, spaced at 20 feet or le_ss along the walls should be. employed. Vertical expansion control joints should be infilled with a flexible grout. Wall footings should b~ keyed or doweled across vertical expansion joints. Walls should be internally grouted and reinforced with steel. Restrained Walls Any retaining walls that will be restrained prior to placing and compacting backfill material or that have re-entrant or male corners, should be designed for an at-rest equivalent fluid pressures (EFP) of 65 pcf,· plus any applicable surcharge loading. This restrained-wall, earth pressure value is for select backfill material or:,ly. For areas of male or re-entrant corners, the restrained waif design shot,Jld extend a minimum distanc·e of twice the height _ ofthe wall laterally from th~ corn-er: Building walls below grade or greater than 2 feet in height should be water-proofed or damp-proofed, depending. on the degree of moisture protection desired. The wall should be drained as indicated in the following section: For i:,tructural footing loads within the 1 :1 zone -of influence behind wall backfill, refer to the following section. Cantilevered Walls These recommendations are for cantilevered retaining walls up to 1 o feet high. Active earth pressure may be used for retaining wall design, provided the top of the wall is· not restrained .from minor deflections. An empirical equivalent fluid pressure approach may be used to compute the horizontal pressure against the wall. Appropriate fluid unit weights are provided .for specifi_c slope gradients of the retained material. These do not include other_ superimposed 1·oading conditions such as traffic, structures, seismic events, expansive soils, -or adverse geologic conditions, If traffic is within a distance H behind any wall or a 1.: 1 projection from the heel of the wall foundation a pressure of ·100 psf per foot in the upper 5 feet shou.ld be _used. Structural loads from adjacent properties and their influence on site walls should be reviewed by the structural engineer, if within a 1: 1 projection behind any site Wall. However, for preliminary planning purposes, one third bf the footing contact pressure should be added to the wall in pounds per square foot below the bearing elevation and for a distance of three times the -footing width along the wall·alignment. Alternatively, a deepened footing beyond the 1 :1 projection (up from the heel) behind the wall may be utilized . Mr. David Bentley · Holly Springs, Carlsbad File: e\wp7\2900\2929a.lge GeoSoils, Ine. W.0. 2929-A-SC October 11, 2000 Page 23 ••••• •• • SURFACE SLOPE OF RETAINED EQUIVALENT FLUID WEIGHT FOR MATERIAL (horizontal to ve.rtical) NON-EXPANSIVE SOIL* ' Level** 38 2 to 1 55. ~To be increased by traffic:· structural surcharge ·and seismic loading as needed. **Level walls are those where grades behind the wall are level for a. distance of 2H. · Wall Backfiil ·and Drainage All retaining walls should be· provided with an adequate bac.kdrain and outlet system (a minimum two outlets per wall and no greater than 100 feet ap~rt), to prevent buildup of hydrostatic· pressures and be designed in accordance with minimum standards ·presented herein. The very low expansive granular backfill should be.provided behind the wall at a 1 :1 (h:v) projection from the heel of the foundation element. Drain pipe should consist of 4-inch diameter perforated schectule ·40 PVC pipe embedded in gravel. Gravel used in the · backdrain systerns should be· a minimum ·of 3 cubic feet per lineal foot of%-to 1-inch clean crushed rock wrapped in filter fa~ric (Mirafi 140 or equivalent) and 12 inches thick behind the wall. Where the void to be fitted is constrained by lot :lines or property boundaries, the use of panel drains (Mirafi 5000 or equivalent) may be considered with the approval of the project geoteqhnical engineer. The surface of the backfill $ho·u1d be sealed by pavement or the top 18 inches compacted to 90 percent relative compacti~n with native soil. Proper surface drainage should also be provided. Weeping of the walls in-lieu of a backdrain is · not recommended for walls greater than 2 fe·et in height. For walls 2 feet or less in height, we·ephbles should be no ·greater than 6 feet on center in the bottom coarse of block and . above the landscap~ zone. · · A paved drainage channel (v-ditch or substitute), either concrete or asphaltic concrete, behind the top of the walls with ~loping backfill. should be considered to reduce the potential for surface wat~r. penetration. For level backfill, the. grade should be sloped such that drainage is toward a suitable outlet at 1 to 2 percent. Retaining Wa~I Footing "transitions . · Site walls are anticipated to be founded on footings desig.ned in accordance with th~ recommendations in this report. Wall footings may transition from formational bedrock to gravefly fill_to select fill. If this condition is present the civil designer may specify either: a) If transitions from rock fill to select fill transect the wall footing alignment at an angle of less than 45 degrees (plan view), then the designer·should perform a m,inimum 2-foot overexcavation for a distance of ~o times the height of the wall and increase overexcavation untir such transition is between 45 and 90 degrees to the wall alignment. · . Mr. David Bentley · · Holly Springs; Carlsbad File: e\wp7\2900\2929a.lge W.O. 2929-A-SC October 11, 2000 Page 24 GeoSoils, Ine. •• •• -•-·· b) Increase of the amount of reinforcing steel and wall detailing (i.e., expansion joints or crack control joints) such that an angular distortion o{t/360 for a distance of 2H (where H=wall .height in feet) on either side of the transition may be accommodated. Expansipn joints should be sealed with a flexible, non-shrink grout. c) Embed the footings entirely into a homogeneous fill. RECOMMENDATIONS-POST EARTHWORK Plar:iting and Landscape Maintenance . Gra_ded slopes constructed within and/or exhibiting or exposing weathered formational materials are considered erosive. Erbded debris may be minimized and surficial slope stability enhanced by establishing and maintaining a suitable vegetation cover s.oon after construction. . Plants selected by the project landscape architect should be light weight, deep-rooted types that require little water and are. capable· of surviving the prevailing ~limate. Graded cut slopes exposing less weathered formational · materials are expected to be relatively non-erosive and will present difficulty for establishment of vegetation on the . - dense formational materials. Jute-type matting or other fibrous covers may aid in allowing the establishment of .a sparse plant cover. Water can weaken the inherent_ strength of all earth materials. Positive surface drainage away from graded slopes should be maintained and only the amount of water necessary to sustain plant life should be provided for planted slopes. Overwatering should be avoided as overwatering the landscape ·area could adversely affect the proposed site improvements. Additional Site Improvements Recommendations for exterior concrete flat work design and construction can be provided upon re_quest, after site earthwork is complete. If, in the future, any additional improvements are planned for the site in general or individual areas, ·recommendations concerning the geological or geotechnical aspects of design and construction of said improvements may be provided upon request. · Footing Tren·ch Excavation All footing trench excavations should be observed by a representative of this office prior to placing reinforcement. Footing trench spoil and any excess soils generated from utility Mr. David Bentley Holly Springs, Carlsbad File: ~\wp7\2900\2929a.lge GeoSoils, lne. W.O. 2929-A-SC October 11, 2000 Page 25 trench excavations should be compacted to a minimum relative compaction of 90 percent •= if not removed the site. •• • ;: :-. . •.. ·: Drainage Positive site drainage should be maintained at all times. Drainage should not flow uncontrolled down any descending slope. Water should be directed away from foundations and not allowed to pond and/or seep into the -ground. Pad drainage should be directed towaro the street or other approved area. Due-to the nature of on-site soils, combined with the_ hardness and permeability of the formational· materials, local areas of seepage may develop due to irrigation or heavy rainfall. Minimizing irrigation wili lessen this potential. .If areas of seepage develop, remedial recommendations for minimizing this effect could be provided upon request. 1. 2. TRENCH BACKFILL All utility trench backfill in structural areas, slopes, and beneath hard scape features should be brought to at least optimum moisture content and then compacted to obtain a minimum relative compaction of 90 percent of the laboratory standard. Flooding/jetting is not recommended for the site ·soil materials. As an alternative, SE 30 ot greater sand, may be flooded/jetted in shallow Linder-slab interior trenches . Sand backfill should not be allowed in exterior trenches adjacent to and within an area extending below a 1 :1 plane projected from the outside bottom edge of the footing. 3. All trench excavations should conform to CAL-OSHA and local safety codes. PLAN REVIEW Project grading p!ans should be reviewed by this office as· they become. Based on our review, supplemental recommendations and -further geotechnical studies (i.e.; rock hardness evaluation~ will likely ·be recommended. Further field work will·· require disturbance and removal of vegetation . Mr. David Bentley Holly Springs, Carlsbad File: e\wp7\2900\2929a.lge · GeoSoils, Ine. W.0. 2929-A-SC October 11, 2000 Page 26 •• • •• INVESTIGATION LIMITATIONS Inasmuch as our study is based upon the site materials observed, selective laboratory testing and limited engineering analysis, the conclusion and recommendations are professional opinions. These opinions have be·en derived in accordance with current . standards of practice, and no warranty is. expressed or -implied. Standards of practice are subject to change with time. These opinions have been derived in accordance with current standards of practice, and no warranty is expressed or implied. St~ndards of practice are-subject to change with time. GSI assumes no responsibility or liability for work. or testing performed by others, for .. our scope-of-work was expressly limited to the evaluation of the sediments/soils underlying the proposed residence. In addition, this report may be subject to review by the controlling authorities. · · · Mr. David Bentley Holly Springs, Carlsbad File: e\wp7\2900\2929a.lge GeoSoils, Inc. W.O. 2929-A-SC October 11, 2000 Page 27 .·; .. ·:·· •·-_ \ .. l ,_. .-. . : ... ~' ·. .·.·. ;,: . .• .-.· . '·.: _; ,. ... : .!· • :-!' ,,• ~: ..... ·· .... · ·• :, ' .... : . . ~ . ' . ·; . . ,•. '-: .. ' .. . ·. ,.!: •-;'' . --~ . '~ . ·, '· . ~ . •··. '· '")._ . -: .. -:· .. ; : . : ~ .'., :·.· .. \-:, .• r• ,, ·., ~-~ . ... . . ... _ .. .. ) : .•. .· .. ·.-... · . · .. ··. ' .. ··~ .. :·., .·;· '·-... '· . ···.· . ........ •,:-· •' 'I .: {. ~ . . · .. ;•· ·,·· ... , ·1/ 'i .. • APPENDIX A REFERENCES Blake, Thomas F., 1997, EQFAUI-T computer ,program and users manual for the deterministic prediction of horizontal accelerations from digitized California faults. Campbell, K.W. and Bozorgnia, Y., 1994, ,Near-source attenuation of peak horizontal acceleration from worldwide accelrograms recorded from 1957 to 1993; , Proceedings, Fifth U.S. National Confetence on Earthquake Engineering, volume Ill, Earthquake Engineering Research Institute, pp 292-293. Greensfelder; R. W., 1974, Maximum credible rock acceleration from earthquakes in Califomia: California Division ofMin~s and Geology, Map Sheet 23. , Hart, E.W., 1994, Fault-rupture hazard zones in California: California Department of Conservation, Division of Mines and Geology, Special Publication 42. Housner, G. W., 1970, Strong' ground motion in Earthquake Engineering, Robert Wiegel, ed.~ Prentice-Hall. Idriss, I.M:, 1994, Attenuation Coefficients for Deep and Soft Soil Conditions , personal communication. ' ' International Conference of Building Officials, 1997, Uniform building code: Whittier, California. Jennings, C.W., 1994, Fault activity map of California and adjacent areas: California Division of Mines and Geology, M~p Sheet No. 6, scale 1 :750,000. Petersen, Ma:rk D., Bryant, W.A., and Cramer, C.H., 1996, Interim table of fault parameters used by the California Division of Mines and Geology to compile the probabilistic seismic hazard maps of California. Sowers and Sowers; 1970, Unified soil classification system {After U. S. Waterways Experiment Station and ASTM 02487-667) in Introductory Soil Mechanics, New York. Weber, F.H., 1982, Geologic Map of north-central coastal area of San Diego County, California showing recent slope failures and pre-development landslides: California Department of Conservation, Division of Mines and Geology, OFR 82-12 LA. Wilson, K.L., 1972, Eocene and related geology of a portion of the San Luis Rey and Encinitas quadrangles, San Diego County, California: unpublished masters thesis, University of California, Riverside. GeoSoils, Ine. ._'r, :·_ .... : •'-... •• ·· .. •. --~-. : · .. :: '·· --: 1. • '.:-·· _, .. , ., . !, ••I _. ... ,1 ,. . '~ •· .. _. ·-· ' ··· . • -· ' . . .,·· : \-. .... · .. :- -:-.· ·' -····. . ·, .. ,: ·. ..-. ·., . ' :. : :··· .. ~-, -~ '• .. .. \ . ·-:., ._.,._ ... ·. ·. ' ~. · .. · ' .. ,:TESTP:IT':LOGS ' ~ • . ... ' = .... • .... . . . . • . . . __ ,,. ,_,· • C' : . . -~-. ·, .. . ; . -~· . :, .. ···:· ·-.. -: ' ... ,· .. :, ·.·. ·,: ··.···.·. ··,····· :.. ... ::.-· .. ·. ~ / __ .,, ·. ·.; :'' '•,• . ~. . . · ... ·: •.'•I . -:· •·. i' ·= •• ·· .. . '; . ·:-: .. . ,, . ·: .. . ... _;.. ~ . ~~ ... -: . ::-· ~ ... , . ... · .. -· .. -:.1 ·,·_ . ·:·· .. , ,•!' ',· :._ • !' ... • i JI· . UNIFIEO SOIL CLASSIFICATION SYSTEM I CONSISTENCY OR RELATIVE DENSITY Majer divisions I Graup I symbols I CRITERIA -.!: ; : .,5! II " .. .., :., cw CP Well-graded gravels md p-avel- sanc:I mixtures. little or no nnes :Poorly graded gravels and gravel-sand mixtures, little er no fines ., CM I .=vels, p-ave. l-sand-silt 1:!~--+----------~ . !!i~ C CC ~· gravel-sand-day i: ... IS 0:, u = -. 0 11:1 SW SP Well-graded suds and gravelly smd.s., little or DO fines Paoriy graded 11Dds md gravelly sands, little or Do fines ~ -= :i · SM Silty smds. sand-silt miUun:S =i~~-----+-----------------1 en 1a, SC ~~ ands, UDd-clay mmiUeS . ML CL St:andard Penetration Te--t Penet.ration Resisui.nc:: 1': (blows/ft) 0-4 4-10 10-30 30-50 >SO Relative Density Very loose Loose Medium Dense Very dense OL biorpuic clays of low· to medium plasticity, p-avelly clays, sandy clays, silty clays. lean clays OrpDic silts and orpmc silty clays of low plutldty Standard Penetration· Test Pcnetranon -Rcsi$.nce N _(blows/ft) Consistency Unconfined Compressive Strength (tons/ft:) Highly Organic Sails I Unified I ~ii class_if. Cobbles, MH CH OH PT biorpmc silts. micaceow or di•tomacec,t•, he mds or silts, elastic silts . biorpmc clays of high plasticity, lat clays -Orpuic clays of medium to high_ pllsticity ·I .Peat, muck, and other highly orpmc soils <2 2-4 4-8 8-15 15--30 ~30 Very soft Soft. Medium Stiff Very stiff Hard <0.25 0.25-0.50 0.50-1.00 1.00-2.00 2.00-1.00 >4.00 l Gravel I · · Sond I 1-,-1_ -coo--rs-e.:::.:.::;=-=l.:.,_f:-:-in_e __ 4-lcoa_rs_e-rl-me"""·-d~iu;;._m=-lr----:f::--in-e---ll Slit or Clay I MOISTURE CONDITIONS MATERAIL QUANTITY OTHER SYMBOLS Dr-y abNnce of 11a1st: duaty, dr-y ta th• touch tr-ace 0 -!5 ,c C Slightly b•low opt1aua aoiature contant _few 5 -10 X s 110tat for CClll)action Mciat near-optimua aoJatura cantent little 10 -25 l B V~ry 110i=it above optiaua actature contant ll0lttl 25 -.. 5 X :tt:. Wet vieibl•. trH water, below water table BASIC LOO FORMAT: Ql"Qup naae, Qrouc ey11bol, (Qrain ai:ze), Color, Moisture., ccneiatency or relative t1enaity Additional conten~a: odor, preance cf roots, ~ica, SYPIIUII, coarse grained carticlee,etc. EXAMPLE: _ Sand {!P), fine to 1tedi1J11 grained, brown, 1101st. loou, tra~ a11t, little tine gravel 1'ew cobblea \lP to 4" in size, sane hair l'"OCta and rootlets Con ... ple SPT UJlple Bulk SUIPle aroundNater- :>res-r-.. •' '. '.··:.:---;~:ttJ\'.[; ·:\:;:--~E~T~::: __ i:_ _ .. ,P,T/.; .,'NO/'. --en r ·--· .. :: SVMBoJi · ·,_ -_-\,. ·_ --;:\'::. .':. ~'. ,rf _.::, .·. ,,::·:_-::1:·~{i~J. .. · V' TP-1,,,, 0-1 Sty'! 1-2. 2-3 -· TP~~ 0-3 SM 3-7 • • • W.O. 2929-A-SC Holly Springs September 19, 2000 LOG OF EXPLORATORY TEST PITS -. :,:-.. :_ .: ~ : ::~f..: ~::.: -. rf ~\l\_\"}:~f :_; \: "i' . \ \i=1ELb:. ~-/ "::'-/i.(: -, . ·_ .. _::;:·sAMPLE7'.~( :.:.:... ' • •:;i!-•:: .. ' . /'.".:,: I, • • • • , _ _. DRv·-···. DESCRIPTION ·-.-,, DEPTH~,!!'._.,,, ;~UVlO_ISTUJ~E. ,; :·,;;: -:.:,,1:'·~--.. ·· . . :,_i-::;t'-(ti l _---/~~? l;;;~J:J~f :~:)f :?:· ·-DENSITY.· ._:.,I'_, •: " ' ~· :~.;. I ' .. ·, •: • • •• .,.,..,,. ••• ' ,..4.~:"t}\•\. -. ·/~:t·t::'i/·\:f)/ ·-·.--./' (pctf'.--· .. _; <;_,"~•I •., •, '., • • -• ' . . . . ~. . . ' . . COLLUVIUM/TOPSOIL: SIL TY SAND with cobbles and · boulders, reddish brown, dry, loose; re>ots. WEATHERED GRANITICS: G.RANITE, reddish brown, dry, loose. GRANITE, light brown to gray, dry, very dense. Refusal@3' No groundwat~r encountered Bi;ickfilled 9-19-00 BULK@0-1 . COLLUVIUM/TOPSOIL: SIL TY SAND, brown, dry, loose; porous,_blockv, roots and rootlets. BULK@3-4 DECOMPOSED GRANITE {Kgr}: DECOMPOSED GRANITE, yellpwish brown, dry, medium dense; blocky, orang iron oxide staininQ, dense with depth. Refusal@?' No groundwater encountered Ai:irl<filli:>rl ~-1 ~-nn PLATE B-1 •• • LOG OF EXPLORATORY TEST PITS •• W;(J. 2929-A-SC Holly Springs September 19, 2000 {tiz-rr..i;rtt l~t! li!i·~ii¾JI ~isa.~;'. 2:~. :,. · ,. ·. · · DESCRIPTION TP-3 V 0-2 I SM I l I I COLLUVIUM/TOPSOIL: $1LTY SAND, light brown to gray, 2-8 8 TP-4 0-1½ SM 1½ dry, loose; blocky, roots and rootlets. , DECOMPOSED GRANITE (Kgr): DECOMPOSED GRANITE, _y_elfowish brown, _darr1p to moist, mE3dium dense. DECOMPOSED GRANITE, yellowish brown to gray, damp, dense . TotaLQepth = 81 . No groundwater encountered Backfilled· 9-19-00 COLLUVIUM/TOPSOIL: SILTY SAND, reddish brown, dry, loose. · · SANTIAGO' PEAK VOLCANICS (Jsp): GRANITE, light brown, dry, very dense. Refusal @ 1 ½' No groundwater encountered " -~kfillc:irl 9-19-00 PLATE 8-2 • • LOG OF EXPLORATORY TEST· PITS • W.O. 2929-A-SC Holly Springs September 19,. 2000 t~~: i1i$1 ~Iii lilt if., ti'lti~: \f :_.i·· .·· · . DESCRIPTION TP-5 0-2 SM 2-3 COLLUVIUM/TOPSOIL: SIL TY SAND, orange brown, dry, loose; blocky, porou~. roe>ts and rootlets. SANTIAGO PEAK VOLCANICS (Jsp): GRANITE, yellowish . brown, dry, very dense. Refusal@3' No groundwater encountered Backfilled 9-19-00 . TP-6\ 0-2½ SM COLLUVIUM/TOPSOIL: SILTY SAND with cobbles and / l?otJlciers, reddish brown, dry, loose. .1 . L,/2½-5 SANTIAGO PEAK VOLCANICS (Jsp): GRANITE:, light brown to gra~ dry, very dense. -------. -~-- Refusal @ 2½'. No groundwater encountered Rackfilled.9-19-00 PLATE B-3 •• • •• • LOG OF EXPLORATORY TEST PITS • W:O. 2929-A-SC · Holly Springs Septe!llber 19, 2000 · ·· , .. -:-,-T·:::-r>i.-.:;_;f{:· :<t ·· · · ··,c1...-.-:7f~ ·+.;~~::.-;:::,.:.;Y\J?~f; \1::i ;, -·:· ... ;·::i: · -<··t--,·, .. TEST. .,. . ... , ... , . . ·.. ,,:.SAMPLI~,;,. ,., ... ~····,.•,,,. ,,. , ., .. , .... ,.-FIELD .. ·, . . ... , .- • j • ••• • ....... ,.j:''' ·. ':·-: .;,i~''!·' . ,' ··:;;;i;i:-:. ·t:·'·_,., .. , . ., ':,;.,. ,,.·?!y::; ·.:·~···~, : . :,_ ... ·:. ·.: PIT,· DEPTH·-·· ··--;:,GROUP.-.:-: _ _.,.,~,,,.DEPTH1:.1::·· ·..-·MOISTURE,~-· , ,.,.·DRY -· ·, . No> · . :. . . (~.+~~-.'.::: --L~~~~;?-~f:~;:;: -~;~i:irt~~{}i~~1:r. Ji1f ;~;~:~i}l~ ,'.~i~1~!A~:: _,: .: : . :· DESCRIPTION TP-7 · 0-2 2-~ . TP-'8 0-1 1-3 COLLUVIUM/TOPSOIL: SILTY SAND, brown, dry, loose; porous, bloc!sY_i·roots and rootlets. SANTIAGO PEAK VOLCANICS (Jsp): METAVOLCANICS, light brown to gray, dry, very dense. Refusal@31 No groundwc;tter encountered Backfilled 9-19-00 COLLUVIUM/TOPSOIL: SILTY SAND, brown, dry, loose; blocky,roots and _rootlet~. SANTIAGO PEAK VOLCANICS (Jsp):. GRANITE, yellowish brown,·d_ry, dense to very dense. · Practical Refusal @ 31 Truck hoe may penetrate AackfiHed_g.._19.nn PLATE 8-4 • • LOG OF EXPLORATORY TEST PITS • W.O. 2929-A-SC Holly Springs September 1.9, 2000 .. '.fEST. :i_-') .:.:. ... :-. -;:'_ .:<"'/r</:\.:jr .. :(~t~AMP~t~?t~ )t ):'_: :\:E/{'/J:;:. ::j·\t=teto ·? . -~:.::·<. ·/:·.·_:' .. ~ >:. :: .. - . ,: PIT .: · . DEPTH· ·:: :_GROUP,<,.: · ·: /DEPTH'~•I<: .?MOISTURE .. :.:-~·:.·,.:DRY ... ·. :/--.:,.· ... · ·.: ·: ·., · DESCRIPTION ' _' •.. '. • • .-~-·· · .• '.: ,,•:,,' •. ;.~11,.:·. 'l1·~t,.:,~.:(: .; • ~·-·~:··:·.:.,' •. , , • ' , •, '.· • , NO .. · ·(ft)·· SYMBOL--·''· ;·,·.-.(ft).-:,, .. ,,,,,~,.,,,,~,:.',(%),.''""···--. · DENSITY· -· '···:· .. · ..... • . • . ...:, .. ; .-:·--:.> .... _>· ·.)}? .... -\·0""</r.::\· \th/:~ .. :',:•/; __ :>\\ . ·!--<(pch:· t _::'_-· .. ,-..\_;_:;\_:_,_.: .. :.·.·. · .. ·. TP-9 '1 0-4· sM 4-7' SM 7-10 COLLUVIUM/TOPSOIL: SILTY SAND, brown, dry, loose; roots and rootlets, blocky, porous. · SIL TY SAND, y~llowish brown, damp to moist, medium dense; porous. SANTIAGO FORMATION. (Tsa): SANDSTONE; yellowish : brown to olive gray, moist, medium dense; interbedded siltstone and clay_stone. Total Depth = 1 O' No groundwater encountered A~f'l<filh:irf 9-19"00 PLATE B-5 • • LOG OF EXPLORATORY TEST PITS • W.O. 2929-A-SC · Holly Springs September 19, 2000 T;; · -:.;ir,: ;;i~i1:· &;jt ~i~tii~:-Jj~ii~ i;I,}·'.~ /:: :.\ DESCRIPTION TP-101V 0-4 Sm 4-5 SM 5-10 SP · COLLUVIUM/TOPSOIL: SILTY SAND, brown, dry, loose; blqc_~. _roots and rootl~ts. · SILTY SAND, reddish brown to olive brown; damp to moist, loose; porous. SANTIAGO FORMATION (Tsa): SANDSTONE, light brown to olive brown, moist to wet, medium dense; interbedded siltstone and claystone . Total Depth== 101• . No Groundwater. encountered backfilled 9-19-00 PLATE 8-6 - • LOG OF EXPLORATORY TEST' PITS • W.O. 2929-A-SC Holly Springs September 19, 2000 . .rEsT· ·. · .. · :,\,·_ ,-.---·: ._·":-> /:::.;. ··;<sA·rJi;;i.~,>::· ?'··.-'.··~::·.::.:{: :· ·:.: :i1· /~·~F,EL~:./ .. .-:~ .. ·. ·. . .. .-· . · PIT,·· .DEPTH_.:-. :: .:GROUP·.".'~ · .. /i,;DEPTH.,:J~~:;: -.,!:.MQISTVRE : · .. .-.... DRY(·) {·/·.t ·: ...... ·.· · . \ NO." . . -(ft~) f).:. '\.:·.Sr~~~~>~ ('.ji;;j.~,~~it:)\ }:!:/f~~ >;:'(:;; --i~.~~;~"!~r;. ·\: __ .,(\' ... ;/;-:.;--·_.·· .: . •' .. 'DESCRIPTION TP-11 V · 0-2 2-3 3-8 COLLUVIUM/TOPSOIL: SILTY SAND, brown, dry, loose; blqcl_<y, .porous, roots. SIL TY SANP, reddish brown,_ moist,_ me_dilJm dense. . SANTIAGO FORMATION (Tsa): SANDSTONE, light yellowish brown, moist, medium dense; interbedded siltstone and claystone. Total Depth= 8' No groundwat~r encountered Rackfilled ~-19_-00 PLATE B-7 ',•, :::· :-: ·, ...... ••• . . ••• ., :· . t.' ·-·:. ,··,.·: .. ~ : . -·.·· . ~. -.. -' . :· .: . ,; t·· .. '. ,,: . ··.:. ,.·. ~: . ...... -·· ;i. :- . , . .·, ·.·:,. :_:..; '·•. .. ~ ·. '.• '~ . ·: . .-· .. _ .. ~· .,:. . -~ -·. : ~--.... ~se·1srv1·,c .. oirA:· · :-:• .•.·, . . ' -··· :,-· ,•: ···.· ;,• ' •I _,,,.;: . . ' ... ··, ·.-. . ···: "<:.:' / . -~ ·: 't' •• SL-1 CALCULATIONS 1st Layer (T1) = R1 x D1' Where: R1 = Velocity (fps) Ratio Factor (V2:V1) .. D1 = Critical Distance 2nd Layer (T2) = R2 x ([?2 -(C1 x T1)) Where: R2= Velocity (fps) Ratio Factor (V3:V2) 02= Critical Distance .C1 = Distance Correction Value (V3:V1) · 3rd Layer (T3) = R3 X (03 -(C1 X T1)+(C2 X T2}) Where: R3 = Velocity (fps) Ratio Factor (V4:V3) D3= Critical Distance C1 = Distance Correction Value (V4:V1) C2= Distance Correction Value (V4:V2) 4th Layer (T4) = R4 X (D4 • (C1 X T1)+(C2'X T2)+(C3 X T3)) Where: R4= Velocity (fps) Ratio Factor (V5:V4) D4= Critical Distance C1 = Distance Correction Value (V5:V1) C2= Oistance Correction Value (V5:V2) C3= Distance Correction Value (V5:V3) Seismic Velocity/Depth Summary V1 = Seismic Velocity (fps) of 1st Layer NE SW V2 = ·Seismic Velocity (fps) of 2nd Layer • Depth.(ft) Velocity (fps) V3 = Seismic Velocity (fps) of 3rd Layer 0 -3.9 1136 V4 = Seismic Velocity (fps) of 4th Layer 3.9 -23.1 4667 23.1 -#### . 6000 SL-1 #### -#jl## 0 NE-SW SW-NE #JI##. -+ 0 + D 10 5.5 D2 110 105 SW NE 03 D~pth (ft) Velocity (fps) D4 0 -2.1 1316 V1 f136 1316 2.1 -19.7 4761 V2 4667 4761 19.7 -#### 6000 V3 6000 6000 #### -"#### 0 V4 #=II## -+ 0 + vs ~~J;ii1t111i~~lli!~i~!j~: J V=1,136-1,316 I NE SW 3.90 2.07 J, T1 19.18 T2 17.66 10' 10' T3 #1#1## #1#1## -,--I V = 4,667 -4,761 I -T4 #1#1## #1#1## 20' 20' T1+T2 23.08 19.73 --T1+T2+T3 #1#1## #1#1## 30' 30' T1+T2+T3+T4 #1#1## #1#1## -- 40' I V2:: 6000 I . 40' --------• 50' 50' ---, ---'- I SCHEMATIC CROSS SECTION l W.O. 2929-A-SC Plate No. C-1 • Seisn .. c Traverse • ..Y ao.o 11 I I I I I I I I I i I · 11 I i i I I f 1 -I J=l ,55.0 50.0 45.0 40.0 u cu 35.0 1h ~ Cl) E 30.0 i= ii> > ~ 25.0 I- 20.0 15.0 10.0 5.0 0.0 NE 1 =1-1-1111·-1111-11111·1·111 ~t~rJ: I ------1-I I I I I I I I I I _I _!-,_,_,_, ,_ ..... J: _ -----~ , I I -, ··1--, I I I I I I I· I I ---.. ·; I I I I' I I I ·- _I I I I I t V3 > 6;000fps -assumed : I : 1 1 1 1 1 1 , • • r -... - I I I I I . I _ I I ·+-----• t I I I I I I I -..._ __ ·j-~~ ' -.----· I \ I I I I I I ·t--·· ---.--· ,-i\ -r i ~ -,- ! i I . I I . '!\ : , , 1 , , , +--=+=.:~-~~-.. -:.: -r I I I I I I ._ I I I J .... -J.~-.. _ \... l T ~ r-i---,-- I , l • I I \ · I I I I I I i I ! i=:-~1~ ~ 1 FF--L:I I I I I ! I I i I I I J 1·· =£~t Pti-42£] r I I IJ=J4*tP4s~i Tl~ ~ _. 1 .. 1 _ _ _I I j ... ----,-.. -----· --. , f:_ -t l ! I._._·_ I , ·rt=+U,,····r_ -I I I ··1 I -+ ..... -, .. -.. :: -·-.. ---------___ _L_ I I . -, 'r.j:9-- 1 I _ _ __ ___ __ t;:::tz~ I 104 I I I ~ ·-:----.. ·1--I I I ~ 14:6=4: r -! _ ~ 1----C._I _ _L_ I_\_L ____ I _I ·· I_ I-___ ......,.. ~~--~----..... .--l_..::::12.3 ,-I -. --r \ -. I -I -r-I --, I -~ l I 21± I ~ I i -ffl ! I I I 11"·~·-667· 1 ! I I i .I I --,. ~ Jf. I -I I . I ' I I I i --, I ~ ·~--~+---+---. I I ! i ! i ·1 ! 1-~--;ir-----,--·-1·--· '""l . 1 • ' I : I - 1 ---~ \I. =11<U~fne 1 I I I ' ······ • ; •1-,,u,u,1-'~ i,------..lo =i I_- ""'P" 0 ~ ~I 10 20 30 40 50 60 70 Distance to Geophone (feet) 80 90 100 110 D = 5.5 D = 105 120 SW Traverse Date: 9/7/00 Orientation: N 37 E . Traverse No.: SL-1 W.O. 2929-A-SC Plate No. C-1 a ••• SL-2 CALCULATIONS 1st Layer (T1) = R1 X D1 Where: R1 = Velocity (fps) Ratio Factor (V2:V1) D1 = Critical Distance 2nd Layer (T2) = R2 X (D2 -(C1 X T1)) Where: R2= Velocity (~ps) Ratio Factor (V3:V2) D2= Critical Distance C1 = Distance Correction Value (V3:V1) - 3rd·Layer (T3) = R3 x (D3 -(C1 x T1)+(C2 x T2)) Where: R3= Velocity (fps) Ratio Factor (V4:V3) D3 = Critical Distance C1 = Distance Correction Value (V4:V1) C2= Distance Correction Value (V4:V2) 4th Layer (T 4) = R4 X (D4 -(C1 X T1)+(C2 X Tv+(C3 x T3)) .Where: R4= Velocity (fps) Ratio Factor (V5:V4) D4= Critical Distance C1 = Distance Correction Value (V5:V1) C2= Distance Correction Value (V5:V2) C~= Di~tance Correction Value (V5:V3) Seismic Velocity/Depth Summary V1 = Seismic Velocity (fps) of 1st Layer N s V2 = Seismic Velocity (fps) of 2nd Layer .:: Depth (ft) Velocity (fps) V3 = Seismic Velocity (fp~) of 3rd Layer 0 -3.5 1163 V4-= Seismic Velocity (fps) of 4th Layer 3.5 -20.5 3774 .. 20.5 -#### 6000 SL-2 #### -#### 0 N-S S-N #11## -+ 0 + -D 9.5 14 .. 5 D2 73 49 s N D3 Depth (ft) . ·v:etocity (fps) D4 0 -5.0 1210 V1 1163 1210 5:0 -17.5 333·3 -V2 3774 3333 17.5 -#### 6000 V3 6000 6000 #### -#### 0 V4 #### -+ 0 + vs ~~~::~::i\:~·::·:~~==~:~:·::;i:::l·=·::~~::: N I V = 1, 163-1,210 I s T1 3.45 4.96 •• T2 17.09 12.55 T3 #11### #11### . 10' 10' · T4 #11### #11### ---'-I V = 3,333 -3,774 I 0:---:- 17.51 T1+T2 20.55 20' 20' T1+T2+T3 #11### "#1#1## ..___ T1+T2+T3+T4 #11### #11### 30' I V ~ 6000 I 30' ----- 40' 40' -~ 50' 50' --- I SCHEMATIC CROSS SECTION I W.O. 2929-A-SC Plate No. C-2 ~~-~-"*'-,,.,~~ . ~ ~if!, S ~ .• • &»;, ~\ . ,..f? , ~ • e1sm1c .--.. averse 60.0 ·r:::::r::::c:::r::=r:::::r:::::r:::=r--r-r--i-i--r--r---,--r-~-~-~--:---------1_,~---··' ...1 ! ' l--1 -1 I i--l----------'····--... 55.0 J ___ -l-~-0 ---__ l ___ -1-~-1-__ I __ I ~I I I I I 1 ---~-----+··-·--· .-~ f l t I I I T I I t l --···- I I I I l so.o I I i i J i i i i i i i i I i i i i i f il~I:·_~ I 1 I I I ·· · +- .l : i -+ 45.0 I I ! I I ' 40.0-=i~,,s,iooo•) ; ! ! I I I 1· I I ·I ! ' " ' ' '~L __ , __ ;_ • I I f -, ----I _, I . ,. I I ] t J_ 0 Cl) 35.0 ~ ...,... Cl) E 30.0 j:: iii > e 2s.o ... 20.0 -,-----if ·1 I ! I : I f ! L L =± L J _J --··'·-·--···-·· ···-·--__ , ! I _I. J __ I_ I_ L _: -----,-j----!-----l....--,. ------------. ... . " H I -j bf-t~. I 11 J I_-J_ LJ I !_· I I. __ -~ ·--~~· ·~ · ---· · ~ · t ----l -+ =+ ~o~ ~ I -· I I~ ==t __ :::::.--.:.: _+-=~ ~~~ {j J. ~ L 21,.4_;-······1··· ··I· · ~~-t=_--_r I•·-·-· 1 -1 ·_ ---·1 ~,. -•1 ,I' ~----; ' --~r __ -_ 2f:=t_ --+-+---i • 1 =+_~---+-~--~ ( _:__,~,_ _ . _· ----~. -. . ~ I _ 18.5:,C( ! ····· ···-r···---T .. ! . ~ ~ ' I I I-' m 1··,-· ,~, ~ · · ,--:-:=·-I --~-1 ; -I £ 2-----,~~-~r.:~=J -_-.--__ 7 _________ 1 I I . ~ I ' ' . I 1-t.9 . 1 I ·I ••• 3 . 1 ; _T ______ ......... , •.. .· i. l 15.0 I - 10.0 ,-----1~ I --__ I ' I I ' ' ' I '1 I , N I ----_-i ---: ' ... i:; n ~ ',. I I I I i I _ i I V2 = 3,333fps I I I I I 00 !t:±::i v, -,.,ssJps j I i ! F i ! i I , i I I ·t:>· .. ' }._ J ·····--,--,--i I 0 10 20 30 40 50 60 70 :---1 : D= 9.5 , I D = 73 l Distance to Geophone (feet) 80 90 100 110 D= 14.5 D =49 120 s Traverse Date: 9/7 /00 Orientation: N -S Traverse No.: SL-2 W.O. 2929-A-SC Plate No. C-2a •• SL-3 CALCULATIONS 1st Layer (T1) = R1 X D1 Where: R1 = Velocity (fps) Ratio Factor (V2:V1) D1 = Critical Distance 2nd Layer (T2) = R2 x (02 -(C1 x T1)) Where: R2 = Velocity (fps) Ratio Factor (V3:V2) D2= Critical Distance C1 = Distance Correction Value (V3_:V1) 3rd Layer (1\) ·= R3 X {D3 -(C1 x T1)+(C2 x T 0) Where: R3 = Velocity (fps) Ratio Factor (V4:V3) D3= Critical Distance C1 = Distance Correction Value (V4:V1) C2= Distance Correction Value (V4:V2) 4th Layer (T 4) = R4 X (D4 -(C1 X T1)+(C2 X T 0+{C3 X T3)) Where: R4= Velocity (fps) Ratio Factor (V5:V4) D4·= Critical Distance C1 = Distance Correction Value (V5:V1) C2= Distance Correction Value (V5:V2) C3 = Distance Correction Value (V5:V3). Seismic Velocity/Depth Summary V1 = Seismic Velocity (fps) of 1st Layer NE SW V2 = Seismic Velocity (fps) of 2nd Layer ••• ·- Depth (ft) Velocity (fps.) V3 = Seismic Velocity (fps) of 3rd Layer 0 -3.0 1087 V4 = Seismic Velocity (fps) of 4th Layer 3.0. -15.7 3750 15.7 -##1#1# 6000 SL-3 #ffl -##### 0 .. NE-SW SW-NE "'##If:# -+ 0 + D 8 8 D2 54 94 SW NE D3 D~pth (ft). Velocity (fps) D4 0 -3.2 1136 V1 10_87 1136 3.2 -15 .. 1 5263 V2 3750 5263 15.1 -##### 6000 V3 6000 6000 #### -·##### 0 V4 '##If:# -+. 0 + vs -:::~t:~:=i~~,::-:t~:i=:~:~:~:=~);::i:. NE I V = 1,087 -1,136 I SW T1 2.97 3.21 . l T2 · · 12.71 11.86 ' T3 ##### ##11## ---10' I V=3,750 I "lO' T4 ##### ##11## -I V =5,263 1-,-:._.. T1+T2 15.68 15.08 -20' 20' T1+T2+T3 ##### ##11## ---'-,____ -T1+T2+T3+T4 ##### ##11## I V==: 6000 I 30' 30' -.__ 40' 40' -I- 50' 50' -I- .. I SCHEMATIC CROSS SECTION l W.O. 2929-A-SC Plate No. C-3 Gi > f! !- NE • ••• Seismic • raverse i I 60.0 • I I -I I 1 1 ,--.1 1 r r ,-1 ·1----, -T-T---, __ -~1 ·T·---:, ,· --t.:_ __ =·:~T·:·.-·.:~.!-~.:·--.: . . . I I. i I . 55.0 -~ f:._ 50.0 I I I i i I i -----!-'----+-----t----+---+---+---+------t---t--'----,-f---t---t-' -~==t==i==*==l==~===l==j~==F==~==i=~f= +--+ i·· I I I I r. i-···---l- 1 I • 1 '··-·-·· ··1---1---.j.. . ·1-- _, __ --'- I I -T I F--r---·--r--~:!:· .. ---·. r-: 1:-, ·---~--+----+ . i• I I · I I r -~., 4 1 ·LJ I i I c=I E f ... L.. ... '[ t==t:=~=l=+-+--1-t-t±=t=t==r::' ·-·---=--·i---·-·l .. -.... . t =:i::==l=-.:=t--+-t--t~+-t=::l=::t=:c:::::il ... _.____ ---+--:_:.::.: :· .... :: ._. . . ! ' I I I I F=f -----!~-I V3 > 6,0ciOfps I J __ ,, I_ I I I ~--; I I .... f" .... ._ _ ___,,__ _ _,_ __ _,_ __ _,_ __ .,__ ____ _,. __ ........ __ .,._~_,_ ____ __,_ __ _,_ __ ....... __ I · I 7' -1~ ---\,----t-----·i------+---~--\ ! I I ,-·-I I ! ! --: I ---i----==r--~.. : -1· • ' l I ... -··---·[-·---;.-.... i ·, • ; · 1 ---··1--1----. . ' ! L ! -1 1 . :i_-:-1 · _ -t--····1-----·-·r ~ ;t=+ 20.0 . I I I· I I --· _.,___,__ I -------1· . I . --1~ l ---0:-; ----0 -·t-·-·-·-1 ·-..... 1--_p---I I I I . -s . ,;j 4 I I i -..f-·-·--·1------·f·---. --I j I I i .-:r=:ttf1 ----I --···f· .. _, .. ·-·1----------T--· ..... _ ... -..... .... ---· -·--i:--7·-------, , -, i--·1 I ---.. . 114 .. J._________ -----r------+-----·---·---- . ' I --· ·····----I' I I --I ., .. 1 I I I l. ---I IL..O . ~ I 1· 15.0 1 ~ __J , 1 1 t • • ·-·-·-----t--... , .. •--1--/, , ~ rs:-4 1·-. . 1 , 1 .-. -'---····\··---10:7--·-;------.. / I i .-1 I· _ '\ r I I I : · I ..,_ ' ,' ·-··-·I-· ----. :. / I 1 ..--1 , ~ , 1 1 1 • , 1 , 1 ;--. . __ ;__. 9,0 1 I I I I I I 1• I I T"-,,. I, 1 10 0. I : / ...--,,, 1 1 1 1 I V2=3,750fps I I I I ·11 I __ l.,. _____ ~~-----. ! .. . y ~ I .J . . . . ------IA,-::;,-::-I I ! I I . -----I. . ! / I ·-t--'T ____ -··, --· .. , . .. . : -11 011 I I i ! 1 V-5263fpsl' : 1 ·-1-··----:-........ ; i 4·4 / _I · I I I I I 2 ' /J -·r ----'-····---t··"-·· J ; • I , I 1-~1~, --,---L-r-----~, ------'.J ; ; ·, i I ··-1. -· --· , 2o.6 -o 6 1 I j -· 1 --·-• 24 3 : . i I' I ::;..---1 I I __ , ,-·-2l8··---1---'j' . ~ I ~ , ~2.4 1 22:s-· · r·---·r--··-:---i · 1 5. 0 i L --1 I -. :I. : I I : I ' I. .• .. • :. -· .• -'.. ... .. ..!. : . • , ---=/·faj~~ ::~··:~~~~r~:+-···-·, i · 1· . :i i : I ·1. ·1 i i ···-·--+~4~1 v~ ~~~~ I· . y : ' " . •·-/--;---==r-;-~ . T ~. ----! --I ---I I ' ----i-I I • o.ov "'"_...__:i:::::'."'::l ~ 10 I V1 = 1,0B7fps r I D= 8 20 30 ! D=54 40 50 60 . 70 Distance to G~ophone (feet) 80 90 100 110 0=8 D = 94 120 SW Traverse Date: 9/7/00 Orientation:. N 15 E Traverse No.: SL-3 W.O. 2929-A-SC Plate No. C-3a •• SL-4 CALCULATIONS 1st Layer (T 1) = R1 X D1 Where: R1 = Velocity (fps) Ratio Factor (V2:V1) D1 = Critical Distance 2nd Layer (T2) = R2 x (D2 -(C1 x T1)) Where: R2= Velocity (fps) R~tio Factor (V3:V2) D2= Critical -Distance C1 = Distance Correction Value (V3:V1) 3rd Layer (T3) = R3 X (Da -(C1 X T1)+(C2 x T ~) Where: R3= Velocity (fps) Ratio Factor (V4:V3) D3·= Critical Distance C1 = Distance Correction Value (V4:V1) C2= Distance Correction Value (V4:V2) .. 4th Layer (T 4) = R4 x (D4 -(C1 X T1)+(C2 X T ~+(C3 X T3)) Where: R4= Velocity (fps) Ratio Factor (V5:V4) D4= Critical Distance . C1 = Distance Correction Value (V5:V1) C2= Distance Correction Value (V5:V2) C3= Distance Correction Value (V5:V3) Seismic Velocity/Depth Summary V1 = Seismic Velocity (fps) of 1st Layer NW SE V2 = Seismic Velocity (fps) of 2nd Layer •• Depth. (ft) Velocity (fps) V3 = Seismic Velocity (fps) of 3rd Layer 0 -3.5 1220· V4 = Seismic Velocity (fps) of 4th Layer _3.~ -30.9 3670 30:9 -'####' 6000 SL-4 #11## -#### 0 NW-SE SE-NW ##II# -+ 0 + D 10 5 D2 113 120 SE NW D3 Depth (ft) Velocity (fps) D4 0 -1.8 1087 V1 1220 1087 1.8 -31.6 3604 V2 3670 36,04 31..6 -#### 6000 V3 6000 6000 #### -#### O: V4 #### -+ 0 + vs ·:r:;~;:tr;~;·~:;~;·};·:;~;~;:i~rt \ V = 1 ,087 -1 ,220 \ T1 :f.54· 1.83 NW 1 SE T2 27.37 29.80 .. T3 . #1#1## '#11### 10' 10' T4 #1#1## '#11### --T1+T2 30.91 31.63 I -V = 3,604 -3,670. I 20' 20' T1+T2+T3 #1#1## '#11### --T1+T2+f3+T4 #1#1## '#11### 30' 30' --,. ··-40' I V ==!: 6000 I 40' -- 50' 50' ---- I SCHEMATIC CROSS SECTION l · W.O. 2929-A-SC Plate No. C-4 • •• Seismic · 1 raverse 600 · · . I I I I I · · I I I I I I I I . I ! : . ! I I I I I : I I ' ---t -I 1---I ..... -· l··-·"··+·- 55:0 .• I I I I I I I I •·--·----f-·----¼-• I ···········l-·····--1-... -+----+---+---+--+----1---l----1---'-1--l----1--'---L-+ .. -. ·i ........ , ... . ! R . ~ I 50 0 ,1-···-·--t"-·-· I j I . ' ' I j ' ' ' , . L_. V~ > 6,000fp~ -ass~med : . _ i i ·. . l ··-j· ·i V3 ~ 6,000~ps -as~umed I . 1· . I . 1 I T : ; ·---· .,. .... .. i 45 .o : ~ i i I I I I I I I I i : I I I i ,--~-,----.-1 400 ~+, -• : : : : • • 1 : •-: r~-t~l:r i\. ' l-" I · I . I I I · .,. ~,r.u··-·--· 1 1 1 , 1 ·••• ·i .. I · · '1 ! I ~-----··-· · I I I · I ' I···-··: .. i ·-~"···1 I -,I~~'---··'----· ! I I .1 ·!·-···+·-··· , .. , ·i·· . •' I ' 0 35 0 ..._ .......::. n j I ·1 ·I I ·r' .~. ,J., . -,;. .. . • G) • . , -·----+--f---+---1----l----1--+-, I i ! , U) ~4~---~g-• ~----· I' : I ! i -1~.· .. ·I_ ... i _,~;-:} ~ ~===-::.~:~ ·---·-_____ r-::..· a·.. , : r ; -·--__ -, -~-::.:::_}-~-.-:-! . -··34.-1 · i E 30.0 . . 1 --1 1 1 r 1 ,,_) .. ,,.... ••• + ... , ... 1 • • i= ·---+---·-·ii____ : --... :....... zi'.:: I i I i I I _ _-~--JQ·B . , +.. 1 • ---j-··--·-· . 1 ,.____ -\ 1 -~ ,....... ~ · __ :'.. ·• j. C1> ... .:::.~--=r~-.-.-:.:·::: ,--·-··· ., ·1 ....._ ---_ • I , : ....... -213:-4----;-'-·· .. ~ .. . . I· : iu 25 0 ·-1 I , -I ...__ 2 ' I 1 ~ 'I r···-··-·1 ..... ,! I--.· ...... ··---···-j--·-'· • I • · ~-----2-a,.9-.J-' . I ... . ~ _l_ ' -I ~ I .A' '=-==± . ···--·--·-"" ·1·-··· ···"t-· .... ,.. -2 3 I • I .-l._.,_,.L .. L . . · ____ ..... ····-·'··+· ' ---~ ~2-~:8--~ . ~ I__ I . 1····-· .t ... ---=----···----"_ --i--·· -' ·---· -----: _-_.. __ ~ HL4 _J . -... I ......... .. ... j ---------·--··-i I · -1.~~;5--. _!._1·--·--'-t-··-r-·---.. ·-~ ... -i. 20.0-$ I -, ~ 1~1:c i ·. =+-I ::--4 ... J:= ----L.. ' I ts.;. ~-_i. l.~~95 ·--r I --.. j·-.. =~·~: ... ·--~:·_: ____ ' --·-·,·---=-_ I 1'7,.5 I _ • _ I • _ " 10.U ----1-·--i·-7_----J-,-~.5 j ' I ··! ..... 7 .... _:..-=--~ ~ ~:-..--=-~~ .:· -··-T I I ! I I I : 10 .0 ~ .... -... -. t I I I }~---++---,""c..~:-~-:: ..... -::.+-1_., I ' I I I I I ' __ , i .. i 5.0 -I ! b,,,~~==,~ i I j I I I -:---;--·-i' ' __ ,_,.: ____ , __ -i--· 0.0 V1 = 1.163fps I I , ; -----,---·--: ! -~ .. i ... ·: ..... ! ___ _I 1• 1 1 1 ----·I 1/1 = 1.064fps ; NW 0 ~ ~ Traverse Date: 9/7/00 Orientation: N 56 W 10 20 30 40 50 60 70 Distance to Geophone (feet) Traverse No.: SL-4 80 90 100 110 D=5 D = 120 120 SE W.O. 2929-A-SC Plate No. C-4a .. · .. · .. '• . •': : ., ··: ·-: ........ e.: • .-... ,, ... . ·· . ; ~---~- ·· .. ·····, ... : .... ..·· ,,. ,:'• . . ·, .. ' .. ,• or '•'• 0 # ·· .. : ·. ~ ... ... . · .··.· ,: ·. ·:-. .·.· ..... :•,. ·-·:· ·. . :···· ' '1 ·• ,. 'G~~eRAL ~RtHwoa~~:Jf GFlA01NG,'Gu10El,Ns~ ., • I : .~, ,:, .. ·.:· ·:· ...... ·, ·' . ·I': . . ,,. ; I _'i ... (' .··· . .. .. ·1·. ;._. \ . •-·. ••• : . GENERAL EARTHWORK AND GRADING GUIDELINES General These guidelines present general procedures and requirements for earthwork and grading as shown· on the approved grading _plans, including preparation of areas to filled, placement of fill, installation of subdrains and excavations. The recommendations contained in the geotechnical report are part of the earthwork and grading guidelines and would supersede the provisions contained hereafter in the case of conflict. Evaluations performed by the consultant . during the course of grading may result in . new recommendations which could supersede these guidelines or the recommendations contained in the geotechnical report. . The contractor is responsible for the satisfactory completion of all earthwork .in accordance with provisions of the project plans and .specifications. The project soil engineer and engineering geologist {geotechnical consultant) or their representatives should provide · observation and testing services, and geotechnical consultation during the duration of the project. · EARTHWORK OBSERVATIONS AND TESTING G·eotechnical Consultant Prior to the commencement of grading, a qualified geotechnical consultant {soil engineer and engineering geologist) should be employed for the purpose of observing earthwork procedures and testing -the fills for conformance with the recommendations of the · geotechnical report, the approved grading plans, and applicable grading codes and ordinances. The geotechnical consultant should provide testing and observation so that determination may be made that the work is being accomplished as specified. It is the responsibility of the cbntractor to assist the consultants and keep them apprised of anticipated work schedules and changes, so that they may schedule ·their personnel accordingly. All. clean-outs, prepared ground to receive fill, key excavations, and subdrains should be observed and documented by the project ·engineering geologist and/or soil engineer prior to placing and fill. It is the _contractors's responsibility to notify the engineering geologist and soil engineer when such areas are ready for observation. Laboratory and Field Tests Maximum dry density tests to determine the degree of compaction should be performed in accordance with American Standard Testing Materials test method ASTM designation D-1557-78. Random field compaction tests should be performed in accordance with test method ASTM designation D-1556-82, D-2937 or D-2922 and D-3017, at intervals of approximately 2 feet of fill height or every 100 cubic yards of fill placed. These criteria GeoSoils, Ine. would vary oepending on the soil conditions and the size of the project. The location and • frequency-of testing would be at the discretion of the geotechnical consultant. • • Contractor's Responsibility All clearing, $ite preparation, and earthwork performed on the projectshould be conducted by the contractor, with ob_servation by geotechnic~J--consultants and staged approval by the governing ag.encies, as applicable .. It is the contractor's respons_ibility to prepare the ground -surface to receive the fill, to the satisfaction of the soil engineer, and to place, spread, moisture condition, mix and compact the fill in accordance with the recommendations of the soil engineer. The contractor should also remove all major non- earth material considered unsatisfactory by the soil engineer. It is the sole responsibility of the contractor to provide adequate equipment and methods to accomplish the earthwork in ~ccordance with applicable grading guidelines; codes or agency ordinances,. and approved grading plans. Sufficient watering apparatus and compaction equipment should be provided by the contractor with due cons.ideration for the fill material, rate of placement, and climatic conditions. If, in the opinion of the geotechnical consultant, unsatisfactory conditions such as questionable weather, excessive oversized rock, or deleterious material, insufficient support equipment, etc., are· -resulting in ·a quality of work that is not acceptable, the consultant will inform the contractor, and the contractor is expected to rectify the conditions, and if necessary, stop work until conditions are satisfactory. · · During construction, the contractor shall properly grade all surfaces to maintain good drainage and prevent ponding of water. The contractor shall take remedial measures to control--surface water and to prevent erosion of graded areas until such time as permanent drainage and erosion control measures· have been installed. SITE PREPARATION All major vegetation, including brush, trees, thick grasses, organic debris, and other deleterious material should be removed and disposed of off-site. These removals must be -concluded prior to placing fill. Existing fill, soil, alluvium, colluvium, or rock materials c;f eterminec;f by the soil engineer or engineering geologist as being unsuitable in-place ·sho_uld be removed prior to fill placement. Depending upon the soil conditions, these materials may be reused as compacted fills. Any materials incorporated as part of the compacted fills should be approved by the soil engineer. Any underground structures such as cesspools, ciste~ns, mining shafts, tunnels, septic tanks, wells, pipelines, or other structures not located prior to grading are to be removed or treated in a manner recommended by the soil engineer. Soft, dry, spongy, highly fractured, or .otherwise unsuitable ground· extending to such a depth that surface processing cannot adequately improve the condition should be overexcavated down to Mr .. Dayid Bentley File: e:\wp7\2900\2929aJge GeoSoils, Ine. Appendix D Page2 •• • · firm ground and approved by the soil engineer before compaction and filling operations continue. Overexcavated and processed soils which have been properly mixed and moisture conditioned should be re~compacted to the minimum relative compaction as specified in these guidelines. Existi'ng ground which is determined to be satisfactory for support of the fills should be scarified to a minimum depth of 6 inches or as directed by the soil engineer. After the scarified ground is brought to optimum moisture content or· greater and mixed, the materials should be compacted as specified herein. If the scarified zone is grater-that 6 inches in depth, it may be necessary to remove the excess and place the material in lifts restricted to about 6 inches in compacted thickness. Existing ground which is not satisfactory to support compacted fill should be overexcavated as r~quired in the geotechnical report ct by the on-site soils engineer and/or engineering geologist. Scarification, disc harrowing, ·or other acceptable form of mixing shoul9 continue until the soils are broken ·down and free of large lumps or clods, until the working surface is reasonably uniform and free from -ruts, hollow, hummocks, or other uneven features which would inhibit compaction as described previously. · Where fills are to be placed on ground with slopes steeper than 5:1 (horizontal to vertical), the ground should be stepped or benched. The lowest bench, which will act as a key, should be a minimum of 15 feet wide and should be at least 2 feet de.ep into firm material, and approved by the soil engineer and/or engineering geologist. In fill over cut slope conditions, the recommended minimum width of the lowest bench or key is also 15 feet with the key founded on firm material, as designated by the Geotechnical Consultant. As a general rule, unless specifically recommended otherwise by tt,e Soil Engineer, the minimum width oHHI keys should be approximately equal· to ½ the height of the slope. Standard benching is generally 4 feet (minimum) vertically, exposing firm, acceptable material. Benching may be used to remove unsuitable materials, although it is understood that the vertical height of the bench may exceed 4 feet. Pre-stripping may be considered for unsuitable materials in excess of 4 feet in thickness. All areas to receive fill, including processed areas, removal areas, and the toe of fill benches should be observed and approved by the soil .engineer and/or engineering geologist prior to placem~nt of fill. Fills may then be prop~rly placed and compacted until design grades (elevations) are attained. COMPACTED FILLS Any earth materials imported or excavated on the property mc;ly b~ utilized in the fill provided that each material has been determined to be suitable by the soil engineer. These materials should be free of roots, tree branches, other organic matter or other deleterious materials. All unsuitable materials should be removed from the fill as directed Mr. David Bentley · File: e:\wp7\29P0\2929a.lge GeoSoils, Ine. Appendix D Page 3 ••• ._,. .• :. by the soil engineer. Soils of poor gradation, undesirable expansion potential, or substandard strength characteristics may be d_esignated by the consultant as unsuitable and may require blending with other soils to serve as a satisfactory fill material. . . Fill materials derived from benching operations should be dispersed throughout the fill area and blended with other.bedrock derived material. Benching operations should not result in the benched material being placed only within a single equipment width away from the fill/bedrock contact. Oversized materials defined as rock or other irreducible materials with a maximum dimensio"n greater than 12 inches should not be buried or placed in fills unless the location of materials and disposal methods are specifically approved by the soil engineer. Oversized material should be taken off-site or placed in accordance with recommendations , of the soil engineer in areas designated as suitable for rock disposal. Oversized material should not be placed within 10 feet vertically of finish grade (elevation) or within 20 feet horizontally of slope faces. To facilitate future .trenching, rbck should not be placed within the range of foundation excavatic;,ns, future utilities, or underground construction unless specifically approved by the soil engineer_ and/or the developers .representative. If import material i~ required for grading, representative samples of the materials to be utilized as compacted fill should be analyzed in the laboratory by the soil engineer to determine its physical properties. If any material other than that previously tested is encountered during grading, an appropriate analysis of this material should be conducted by.the· soil engineer as soon as possible. Approved fill material should be placed in areas prepared to receive fill in near horizontal layers that when compacted should not exceed 6 inches in thickness. The soil engineer may approve thick lifts if testing indicates the grading procedures are such that adequate compaction is being achieved with. lifts of greater thickness. Each layer should be spread evenly and blended to attain uniformity of matericd and moisture suitable for compaction. Fill layers at a moisture content less than optimum should be watered and mixed, and wet · fill layers should be aerated by scarification or should be blended with drier material. Moisture condition, blending, and mixing of the fill layer should continue until the fill materials have a uniform moisture content at or above optimum moisture. After each layer has been evenly spread, moisture conditioned and mixed, it should be uniformly compacted to a minimum of 90 percent of maximum density as determined by ASTM test designation, D-1557-78, or as otherwise recommended by the soil engineer. Compaction equipment should be adequately sized and should be specifically designed for. soil. compaction or of proven reliability to efficiently achieve the specified degree of co_rnpaction. · Mr. David Bentley File: e:\wp7\2900\2929a.lge GeoSoils, Inc. Appendix D Page4 • : .. ... Where tests indicate that the density of any layer of _fill, or portion thereof, is below the required relative compaction, or improper moisture is in evidence, the particular layer or portion shall be re-worked until the required density and/or moisture content has been attained. ~o additional fill shall be placed in an area Until the last placed lift of fill has been tested and found to meet the density and moisture requirements, and is approved by the soil engine~r. Compaction of slopes should be accomplished by over-building a minimum of 3 feet horiz_dntally, and subsequently trimming back to the design slope configuration. Testing shall be performed as the fill is elevated to evaluate compaction as the fill core is being d~veloped. Special efforts may be necessary to attain the specified compaction in th~ fill slope zone.. Final slope shaping should be performed by trimming and removing loose materials with appropriate equipment. Afinal determination of fill slope compaction ~hould be_ bas~d on observation and/or testing of the finished ·slope face. Where compacted fill slopes are designed steeper than 2: 1 (horizontal to ·vert!cal), specifiq material types, a higher minimum relative compaction, and special grading procedures, may be recommended. · · If an alternative to over-building and cutting back the-compacted fill slopes is selected, then special effort should be made to achieve the required compaction in the outer 1 o feet of ea.ch lift of fill by undertaking the following: 1 . An extra pi~ce of equipment consisting of a heavy short ·shanked sheepsfoot should · be used to roll (horizontal) parallel to the slopes continuously as fill is placed. The sheepsfoot roller should also be used to roll perpendicular .to the slopes, and extend out over the slope_ to provide adeqt,Jate ·compaction to the face of the slope. 2. Loose fill should not be spilled_ out over the face of the slope as each lift is compacted. Any loose fill spilled over a previously completed slope face should be trimmed off or be subject to re-rolling. 3. Field compaction tests will be made in the outer (horizontal) 2 to 8 feet of the slope at appropriate vertic~ll intervals, subsequent to compaction operations. 4. After completion of the slope, the slope face should be shaped with a small tractor and then re-rolled with_a sheepsfoot to achieve compaction to near the slope face. Subsequent to testing to verify cdmpaction, the slopes should be grid-rolled to achieve compaction to the slope face. Final testing should be used to confirm compaction after grid rolling. 5. Where testing indicates less than adequate compaction, the_ contractor will be responsible to rip, water, mix and re-compact the slope material as necessary to achieve compaction. Additional testing should be performed to verify compaction. Mr. David Bentfey File: e:\wp7\2900\29~9a,lge GeoSoils, Inc. Appendix D Pages •• • 6.-Erosion control and drainage devices should be designed by the project civil engineer in compliance with ordinances of the controlling governmental agencies, arid/or in accordance with the recommendation of the soil engineer or engineering geologist. SUBDRAIN INSTALLATION· Subdrains should be install~d in approved ground in accordance with the approximate alignment and details indicated by the geotechnical consultant. Subdrain locations or materials should· not be changed or modifi~d without -approval of the geotechnical consultant. The eoil engineer and/or engineering geologist may recommend and direct· changes in subdrain line, grade · and drain material in the field, pending exposed conditions. The location of constructed subdrains should be recorded by the project civil engineer. · EXCAVATIONS Excavations and cut slopes should ·be examined during_ grading by the engineering geologist. If directed by the engineering geologist, further excavations or overexcavation and re-filling of cut areas should be performed and/or reme_dial grading of cut slopes should be _performed. When fill over cut slopes are to be graded, unless otherwise approved, the cut portion of the slope should be observed by the engineering geologist prior to placement of material$ for construction of the fill portion .. of the slope. The'-engineering geologist should observe all cut slopes and should be notified by the contractor when cut slopes are started .. If, during the course of grading, unforeseen adverse or potential adverse ·geologic conditions are encountered, the engineering geologist and soil engineer should · investigate, evaluate and make recommendations to treat these problems. The need for cut slope buttressing or stabilizing should be based on in-grading evaluation by the engineer:ing geologist, whether anticipated or not. · Unless otherwise specified in soH and geological ·reports, no cut slopes should be excavated higher or steeper than that allowed by the ordinances of controlling governmental agencies. Additionally, short-t~rm stability of temporary cut slopes is the contractors responsibility. Erosion control and drain~ge devices should be designed by the project civil engineer and shoul_d be constructed in compliance with the ordinances of the controlling governmental agencies, and/or in accordance with the r~commendations of the soil engineer or engineering geologist. ·Mr~ David-Bentley File: e:\wp7\2900\2929a.lge GeoSoils, Ine. Appendix D Page 6 ·-- ·- • COMPLETION Obseryation, testing and consultation by the geotechnical consultant should be conducted during the-gradirig operations in order to state an opinion that all cut and filled areas are graded in accordance with the approved project specifications. After completion of grading and after the soil engineer and engineering geologist have finished their observations of the work, final reports should be submitted subject to review by the controlling governmental agencies. No further excavation or filling should be undertaken without prior notification of the ·soil engineer arid/or engineering geologist. All finished cut and fill slopes should be protected from erosion and/or be planted in accordance with the project specifications and/or ·as recommended by a landscape architect. Such protection and/or planning should be undertaken as soon as practical after completion of grading. JOB SAFETY General At GeoSoils, Inc. (GSI) getting the job done safely is <;>f primary concern. The following is ·the company's safety considerations_ for use by all employees on multi-employer construction sites. On ground personnel are at highest risk of injury and possible fatality on grading and construction projects-. GSI recognizes that construction activities will vary on each-site and tha~ site· safety is the prime responsibility-of the contractor; however, everyone must be safety conscious and responsible at all times. To achieve our goal of avoiding accidents, cooperation between the client, the contractor and GSI personnel must be maintained. In an effort to minimize risks associated with geotechnical testing and observation, the following precautions are to be implemented for the safety of field personnel on grading and construction projects: Safety Meetings: GSI field personnel are directed to attend contractors regularly scheduled and documented s~fety meeti'ngs. Safety Vests: Safety Flags: Mr. David Bentley File: e:\wp7\2900\2929a.lge Safety vests are provided for and are to be worn by GSI personnel at all times when they are working in the field. Two safety flags are provided tb GSI field technicians; o_ne is to be affixed to the vehicle when on site, the other is to be placed atop the spoil pile on all test pits. · GeoSoils, Ine. Appendix D Page 7 •• • . . Flashing Lights: All. vehicles stationary in the grading area shall use rotating or flashing amber beacon, or strobe lights, on the vehicle during all field testing . While operating a vehicle in the grading area, the emergency flasher on the vehicle shall be activated. In the event that the contractor's representative observes any of our personnel not following the above, we request that it be brought to the attention of our office. · Test Pits Location, Orientation and Clearance The technician is responsible. for selecting test pit locations. A primary concern should be the technicians's safety. Effort$ will be made to coordinate locations with the grading contrqctors authorized representative, and to select locations following or behind the established traffic pattern, preferably outside of current traffic. The contractors authorized representative (dump man, operator, supervisor, grade checker, etc.) should direct excavation of the pit and safety during the test period. Of paramount concern should be the soil te.chnicians safety and obtaining enough tests to represent the fill. Test pits should be excavated so that the spoil pile is placed·away form oncoming tr_affic, _ whenever possible. The technician's vehicle is to be placed next to the test pit, opposite the spoil pile. This necessitates the fill be maintained in a driveable condition. Alternatively, the contractor may wish to park a piece of equipment in front of the test holes,·particularly in small fill areas or those with limited·access. A zone of-non-encroachment should be established for all test pits. No grading equipment should enter this zone during the testing procedure. The zone ·should extend approximately 50 feet outw~rd from the center of the test pit. This -zone is established for safety and to avoid excessive grounc;f vibration which typically decreased test results. When taking .slope tests the technician should park the vehicle directly above or below the test location. If this is not possible, a prominent flag should be placed-at the top of the slope. The contractor's representative should effectively keep all equipment at a safe operation distance (e.g. 50 feet) away from the slope during this testing. The technician is directed to withdraw from the active portion of the fill as soon as possible foilowing testing~ the technician's vehicle should be parked at the perimeter of the fill in a highly visible location, well away from the equipment traffic pattern. The contractor should inform our personnel of all changes to haul roads, cut and fill areas or other factors that may affect site access and site safety. In the event that the technicians safety is jeopardized or compromised as a result of the contractors failure to comply with any of the above, the technician is required, by company policy, to immediately withdraw and notify his/her supervisor. The grading contractors representative will eventually be contacted in an effort to effect a solution. However, in the Mr. Oavid Bentley · File: e:\wp7\2900\2929a.lge GeoSoils, Ine. Appendix D Page a •. :; .. •••• interim, no further testing will be performed until the situation is rectified. Any fill place can be considered unacceptable and subject to reprocessing, recompaction or removal. In the event that the soil technician does not comply with the above or other established safety guidelines, we request that the contractor brings this to his/her attention and notify this office. Effective communication and coordination between the contractors representative and the soils· technician is strongly encouraged in order to implement the above safety pl~n. · Trench and Vertical Excavation It is the contractor's responsibility to provide safe access into trenches where compaction testing is needed. · Our personnel are directed not to enter any excavation or vertical cut which 1) is 5 feet or deeper unless shored or laid back, 2) displays any evidence of instability, has any loose rock or other debris which could fall into the trench, or 3) displays any other evidence of any unsafe ponditions regardless of depth. - All trench excavations or vertical cuts in excess of 5 feet deep, which any person enters, should be shored or laid back. Trench access should be provided in accordance with CAL-OSHA and/or state and local standards. Our personnel are directed not to enter any trench by being lowered or 11riding down11 oh the equipment. If the contractor fails ·to. ptovide safe access to trenches for compaction testing, our company policy requires that the soil technician withdraw and notify his/her supervisor. The contractors representative will eventually be contacted in an effort to effect a solution. All backfill not tested due to safety concerns or other reasons could be subject to reprocessing and/or removal. If GSI personnel become aware of anyone working beneath an unsafe trench wall or vertical excavation, we have a legal obligation to put the contractor and own·er/developer on notice to im·mediately correct the situation. If corrective steps .are not taken, GSI then has ari obligation to notify CAL-OSHA and/or the proper authorities . Mr:·oavid Bentley Fife: e:\wp7\2900\2929a.lge GeoSoils, lne. Appendix D Page9 ••• . .. "' • CANYON SUBDRAIN DETAIL TYPE A SEE ALTERNATIVES TYPE 8 ____ __, _____ ~------------------------------- , PROPOSED COMPACTED FILL ' ', -'-', _ _....--NATURAL GROUND -=~ '-JI: 14\\\ ', t'lt SEE ALTERNATIVES NOTE: ALTERNATIVES, LOCATION AND EXTENT OF SUBDRAINS SHOULD BE DETERMINED BY THE SOILS ENGINEER AND/OR ENGINEERING GEOLOGIST DURING GRADING. PLATE EG-1 •• ••••• •• CANYON SU BO RAIN ALTERNATE DETAILS ALTERNATE t PERFORATED PIPE AND FILTER MATERIAL · A-1 : FILTER MATERIAL. . S)EVE SIZE · PERCeNT PASSING 1 INCH . , 100 ·3/ 4 INCH 90~100_. J/8 INCH 40-100 NO. 4 25-40. N0.8 18-33 .NO. JO :6-15 ·No. SO .0-7. NO. 200 0-3 ALTERNATE 2: PERFORATED PIPE, GRAVEL AND. FILTER FABRIC ~NIMUM OV~RLAP . 6" MINIMUM OVER~~, A-2 PERFORATED PIPE: SEE ALTERNATE 1 GRAVEL: CLEAN 3/ 4 INOi Rba< OR APPROVED SUBSTITUTE FILTER FABRIC: MIRAFI 140 OR APPROVED SUBSTITUTE PLATE EG-2 • • ,. DETAIL FOR FILL SLOPE TOEING OUT ON FLAT ALLUVIA TED CANYON TOE OF SLOPE AS SHOWN ON GRADING PLAN ORIGINAL GROUND SURFACE TO BE RESTORED WITH COMPACTED FILL -L~GI_NAL_:~~U:A~ BACKCU~~ARIE_S. FOR DEEP_ REMOVALS, L-._~~ r · . . BACKCUT ~\f\.SHOULO BE MADE NO /.._-$'~ STEEPER ·THA~:1 OR AS NECESSAR.:'f ~"),~ ANTICIPATED ALLUVIAL REMOVAL FOR SAFETY '-~'\.CONSIDERATIONS7 / .' 1 ~ DEPTH PER SOIL ENGINEER. ~,~ / . \'11~/\ . . . "\\ /j~~ PROVIDEA 1:1 M™IMUM PROJECTIONFROM TOE;;- SLOPE AS SHOWN ON GRADING PLAN TO THE RECOMMENDED REMOVAL DEPTH. SLOPE HEIGHT. SITE CONDITIONS AND/OR LOCAL CONDITIONS COULD DICTATE FLATTER PROJECTIONS . REMOVAL ADJACENT TO EXISTING FILL ADJOINING CANYON FILL ------------_.;.~---------. . PROPOSED ADDITIONAL COMPACTED FILL COMPACTED FJLL LIMITS LIN~\ . , TEMPORARY COMPACTEO FILL ~ --- . )_, FOR DRAINAG_E ONLY ------,,, ~ Qaf . · u-<0, Oaf . / Qal (TO BE REMOVED! !EXISTING COMPACTED FILLI '°~',, {.,, ~;,.~i,§/f~\ · I ~ . 0-~~~\ LEGEND · 'l§JY/~~E ~EMOVED BEFORE Oaf ARTIFICIAL FILL. PLACING ADDITIONAL COMPACTED FILL Oal ALLUVIUM PLATE EG-3 -0 r )> -t n, n, G) I ~ • • • TYPICAL ST ABILIZA Tl.ON I BUTTRE.SS FIL-L DETAIL 15' TYPICAL. 1-2· ---·"; 1\ ...... Jll\(j >->-.t QI OUTLETS TO BE SPACED AT 100' MAXIMUM INTERVALS, AND SHALL EXTEND 1r BEYOND THE FACE OF SLOPE AT TIME' OF. ROUGH GRADING COMPLETION. 14 ~1 BLANKET FILL IF R.ECOMMENDED 15' MINIMUM · BY THE SOIL ENGINEER , '\\Vij\\{7# _____ _ .... ill-~ _,. f I~ ,, ...... 4 ( . • -4. DIAM.ETER NON-PERFORATED OUTLET PIPE _J. ANO BACKDRAIN (SEE ALTERNATIVES) W"'. J'MINIMUM KEY DEPTH • •• \: • TYPICAL STABILIZATION / BUlTRESS SUBORAIN DETAIL 4. MINIMUM 2. MINIMUM PIPE 4. MINIMUM -u r )> -I rn rn. G> I U1 ::1: ::, % ~ % . N 2· MINIMUM FILTER MATERIAL: MINIMUM OF FIVE FP/LINEAR Ft OF PIPF • OR FOUR Ffl/LINEAR Fl OF PIPE WHEN PLACED IN SQUARE CUT TRENCH. AL.TERNA~IYE IN LIEU' OF FILTER MATERIAL: GRAVEL MAY B ENCA~ED IN APPROVED FILTER FABRIC. FILTER" FABRIC SHALL BE MIRAFI 14Q OR EQUIVALENT. FILTER FABRIC Sh1ALL BE LAPPED A .MINIMUM OF 12· ON ALL.JOINTS. MINIMUM 4. DIAMETER PIPE: ABS-ASTM D-2 751, SOR 35 OR AST.M °o-1527 SCHEDULE 40 PVC-ASTM D.:_3034, SPR 35 OR ASTM D-1785 SCHEDULE 40 WI.TH A CRUSHING• STRENGTH OF 1,000 POUNDS MINIMUM, AND A. MINIMUM OF 8 UNIFORMLY SPACED PERFORATIONS PER FOOT OF PIPE INSTALLED WITH -PERFORATIONS OF BOTTOM OF PIPE. PROVIDE CAf1 AT UPSTR·EAM END OF PIPE. S.LOPE AT ;2% TO OUTLET PIPE. · OUTLET PIPE TO BE CONNECTED TO . . . . SUBDRAIN PIPE WITH TE.E OR ELBOW~ ' t-lJTE:-1. TRENCH FOR OUT.LET PIPES TO BE BACKFILLED ' WITH ON-SITE SOIL.' i. BACKDRAINS AND LATERAL DRAINS SHALL BE LOCATED AT EL.EVATION OF EVERY BENCH DRAIN. FIRST DRAIN LOCATED AT ELEVATION JUST ABOVE LOWER LOT GRADE. ADDITIONAL DRAINS MAY BE REQUIRED AT THE DISCRETION OF THE SOILS ENGINEER-AND/OR ENGINEERING GEOLOGIST. Fil TER MATERIAL SHALL BE OF THE FOLLOWING SPECIFICATION OR AN APPROVED EQUIVALENT: SIEVE SIZE PERCENT PASSING 1 INCH 100 3/4 INCH 90-100 3/8 INCH 40-100· NO. 4 25-40 N0.8 18-33 NO. 30 5-15 NO. 50 0-7 NO. 200 0-3 GRAVEL SHAJ._l BE OF THE FOLLOWING SPECIFICATION OR AN APPROVED EQUIVALENT: SIEVE SIZE PERCENT PASSING 1 112 INCH 100 NO. 4 50 N0.200 8 SAND EQUIVALENT: MINIMUM OF 50 • • FILL OVER NA TUR AL DETAIL SIDEHILL FILL TOE OF SLOPE AS SHOWN ON GRADING PLAN PROVIDE A 1:1 MINIMUM PROJECTION FROM DESl·GN TOE OF SLOPE TO TOE OF KEY AS SHOWN ON AS BUILT NATURAL SLOPE TO BE RESTORED WITH ~ ~1 I ~'.MINIM~M. BENCH WIDTH MAY VARY • COMPACTED FILL ~ 4• MINIMUM NOTE: 1. WHERE THE NAtURAL, SLOPE APPROACHES OR EXCEEDS THE -u r )> -I m m G> I O> 15° MINIMUM KEY WIDTH DESIGN SLOPE RATIO, SPECIAL RECOMMENDATIONS WOULD BE · 2·x 3' MINIMUM KEY DEPTH 2' MINIMUM IN BEDROCK OR APPROVED MATERIAL. PROVIDED BY THE SOILS ENGINEER. 2. THE NEED FOR AND DISPOSITION OF DRAINS WOULD BE DETERMINED BY THE SOILS ENGINEER BASED UPON EXPOSED CONDITIONS. • • .... ·· H • • ·, FILL OVER CUT D'ETAIL CUT/FILL CONTACT 1. AS SHOWN ON GRADING PLAN 2.. AS SHOWN ON AS BUILT ORIGINAL TOPOGRAPHY MAINTAIN MlNIMUM 15' FILL SECTION FROM BACKCUT TO FACE OF FINISH SLOPE ----------,-- COMPACTED FILL BENCH WIDTH MAY VARY II{\ BEDROCK OR APPROVED MATERIAL LOWEST BENCH WiDTH 15' MINIMUM OR H/2 -0 r )> --f rn rn G) I 'l NOTE: THE CUT PORTION OF THE ·SLOPE SHOULD BE EXCAVATED .AND EVALUATED BY THE SOILS ENGINEER AND/OR ENGINE·ERING GEOLOGIST PRIOR ·ro CONSTRUCTING THE FILL PORTION. -u r )> -I m m G) I 00 • • • • • ST AB I LIZA TION FILL FOR UNSTABLE MATERIAL EXPOSED IN PORTION ·OF CUT .SLOPE NATURAL SLOPE MATERIAL I REMOVE: UNSTAB·LE MATEijlAL ~ ~ t 1 s· MINIMUM ,~P,~SED FINIS!:I EP YBAD E UNWEATHERED BEDROCK OR APPROVED MATERIAL -COMPACTEO STABILIZATION FILL --i :;--~· MINIMUM TILTED BACK ·'\ ~ z ~ . . I. . W L:::i IF RECOMMENDED BY THE SOILS ENGINEER AND/OR ENGINEERING -. ~ GEOLOGIST, THE REMAINING CUT PORTION OF THE SLOPE MAY f'...c 'H th·,._,.. W1 ~/ -REQUIRE REMOVAL ANO REPLACEMENT WITH COMPACTED FILL. NOTE: 1. SUBDRAINS ARE NOT REQUIRED UNLESS SPECIFIED BY SOILS ENGINEER AND/OR ENGINEERING GEOLOGIST,. 2. ·w· SHALL BE EQUIPMENT WIDTH l15"J.FOR SLOPE HEIGHTS LESS THAN 25 FEET. FOR SLOPES GREATER· , THAN 25 FEET ·w· SHALL BE DETERMINED BY THE PROJECT SOILS ENGINEER AND /OR ENGINEERING GEOLOGIST. AT NO TIME SHALL ·w· BE LESS THAN H/2. -u s;: -I rn rn G) I lO • •• SK·IN FILL OF N,A T·URAL GROUND 15' MINIMUM TO BE MAINTAINED FROM PROPOSED FINISH SLOPE FACE TO BACKCUT - • ORIGINAL SLOPE ~ NOTE: 1. THE NEED AND DISPOSITION OF DRAINS WILL BE DETERMINED! BY THE SOILS ENGINEER AND/OR . ENGINEERING GEOLOGIST BASED ON FIELD CONDITIONS. 2. PAD OVEREXCAVATION AND RECOMPACTION SHOULD BE PERFORMED IF DETERMINED TO BE NECESSARY BY THE SOILS ENGINEER ANO/OR ENGINEERING GEOLOGIST • -0 ~ -I m m G1 I _a, 0 •• • ·:·,: • DAY·LIGHT. CUT LOT DETAIL ___,, I ' ' RECONSTRUCT COMPACTED FILL SLOPE AT 2:1 OR FLATTER (MAY INCREASE OR DECREASE· PAD AREAL OVEREXCAVATE ANO RECOMPACT ---, REPLACEMENT FILL AVOID AND/OR CLEAN UP SPILLAGE OF MATERIALS ON THE NATURAL SLOPE ~ ~ / / NOTE: 1. SUBORAIN AND KEY WIDTH REQUIREMENTS WILL BE DETERMINED BASED ON EXPOSED SUBSURFACE CONDITIONS AND THICKNESS OF OVERBURDEN. 2. PAD OVER EXCAVATION AND RECOMPACTION SHOULD BE PERFORMED IF DETERMINED NECESSARY BY THE SOILS ENGINEER AND/OR THE ENGINEERING GEOLOGIST. TRAN·SITlON .. LOT DETAIL CUT LOT [MATERIAL TYPE TRAN:SITION} - ---------•· I PAO GRADE COMPACTED FILL TYPICAL BENCHING •·;-· •. CUT-FILL LOT (DAYLIGHT TRANSITION) MUM PAD GRADE NOTE: * DEEPER OVEREXCAVATION MAY BE RECOMMENDED BY THE SOILS ENGINEER •.. AND/OR ENGINEERING GEOLOGIST IN STEEP CUT-FILL TRANSITION AREAS. PLATE EG-11' .... • SETTLEMENT PLATE AND RISER DETAIL 2·x 2·x 114· STEl;L P'LATE STANDARD 3/4 •. PIPE NIPPLE WELDED TO TOP OF PLATE. ~-------4--3/4· X 5•GALYANIZED PIPE, STANDARD.PIPE THREADS TOP .AND BOTTOM. EXTENSIONS THREADED ON BOTH ENOS AND ADDEO IN 5' INCREMENTS. 3 _INCH SCHEDULE 40. PVC PIPE SLEEVE, ADO IN 5' INCREJ,4ENTS WITH GLU~ JOINTS. FINAL GRADE ! ][~ i ·MAINTAIN ·5' CLEARANCE OF HEAVY EQUIPMENT • ....i.+ -LA.,-MECHANICALLY HANO COMPACT IN 2· VERTICAL ~ ·~--r'\r LIFTS OR ALTERNATIVE SUITABLE TO AND . ._, ~-:---M ___ .,., · ACCEPTED BY THE SOILS ENGINEER • 1 s· s· 1 I I s· : Al MECHANICALLY HAND COMPACT THE INITIAL s· ) VERTICA~ WITHIN As• RADIUS OF PLATE BASE. / ' . / ' / ' ./ ' . . . . . . . . -. . ........ ·. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ' BOTTOM OF CLEANOUT PROVIDE A MINIMUM 1' BEDDING OF COMPACTED SANO NOTE: 1. LOCATIONS OF SETTLEMENT._PLATES SHOULD BE CLEARLY MARKED AND READILY VISIBLE (RED FLAGGED) TO EQUIPMENT OPERATORS. · 2. CONTRACTOR SHOU LO MAINTAIN CLEARANCE OF A s· RADIUS OF PLATE BASE ANO WITHIN 5' (VERTICAL! FOR HEAVY EQUIPMENT. FILL WITHIN CLEARANCE AREA SHOULD BE HANO COMPACTED TO PROJECT SPECIFICATIONS OR COMPACTED BY ALTERNATIVE APPROVED BY THE SOILS ENGINEER. 3. AFTER s·rv-ERTICAU OF FILL IS IN PLACE. CONTRACTOR SHOULD MAINTAIN As· RADIUS EQUIPMENT CLEARANCE FROM RISER. . 4. PLACE AND MECHANICALLY HANO COMPACT INITIAL 2' OF FILL PRIOR TO ESTABLISHING THE INITIAL READING. 5. IN THE EVENT OF DAMAGE TO THE SE:TTLEMENT PLATE OR EXTENSION RESULTING FROM EOUIPMENT·OPERATING WITHIN THE SPECIFIED CLEARANCE AREA, CONTRACTOR SHOULD IMMEDIATELY NOTIFY THE SOILS ENGINEER AND SHOULD BE RESPONSIBLE FOR RESTORING THE SE.TTLEMENT PLATES TO WORKING ORDER. 6. AN ALTERNATE DESIGN AND METHOD OF INSTALLATION MAY BE PROVIDED AT THE DISCRETION OF THE SOILS ENGINEER. PLATE EG-14 ••• •••• • TYPICAL SURFACE SETTLEMENT MONUMENT F1NISH GRADE -..;..;.;.;.:=-:~:.:_-----.-----------.-------------- .,.._~ 3/a· DIAMETER X s· LENGTH CARRIAGE BOLT OR EQUIVALENT • DIAMETER X 3 1/2" LENGTH HOLE ,.._-J-CONCRETE BACKFILL PLATE EG~15 ··-.- I ---- -Ft.AG ~•-:· '•. TEST PIT SAFETY DIAGRAM 50 FEET SPOIL SIDE VIEW ( NOT TO SCALE ) 100 FEET -. j I ... . -w LL. 0 u, ,_, _ 50 FEET P1LE ·-:·:.:,:·.:~·:-:·:-:·:·.:·:·:,:·:,:·.t:~j :;.-.:,-1:-:-.;-:·-:-:~:-:·:.;-:·.::~.·:t'!····~·-··· :t----1--l~_...J I•' • • ,• ,• • , 0 ,, ..::Y.:t .~~. ~. , .. • xy•:•,:,: _ / ; FLAG APPROXJMA TE CENTER LL. CF TEST PiT ~ ' ' { NOT TO SCALE ) - PLATE EG--16 ••• .. •••• OVERSIZE ROCK 01-SPOSAL VIEW NORMAL TO SLOPE FACE PROPOSED FINISH GRADE QQ cJ:J ·00 co ~ 15" MINIMUM (Al (B) 00-~ ca 20· MINIMUM (GI D 00 c:=o 0c::> co c,O c::,o(F) ViEW PARALLEL TO SLOPE FACE . . PROPOSED FINISH GRADE . 10.MINIMUM (El 15" MINIMUM 0 ex, ~::x::~ ~ .15" MI_NIMUM ~ . BEDRoc·K OR APPROVED MATERIAL NOTE: [A) ONE EQUIPMENT WIDTH OR A MINIMUM OF 15 FEET. (B) HEIGHT AND WIDTH MAY VARY DEPENDING ON ROCK SIZE ANO TYPE OF , EQUIPMENT. LENGTH OF WINDROW SHALL s·E NO GREATER THAN 1 oo· MAXIMUM. ·(CJ IF APPROVED BY THE SOILS E.NGINEER ANDIOR ENGINEERING GEOLOGIST, WINDROWS MAY BE PLACED DIRECTLY ON COMP'ETENT MATERIAL OR BEDROCK PROVIDED ADEQUATE SPACE IS AVAILABLE FOR COMPACTION. . IOI ORIENTATION OF WINDROWS MAY VARY BUT SHOULD ·eE AS RECOMMENDED BY THE SOILS ENGINEER ANO-/OR ENGINEERING GE·OLOGIST. STAGGERING OF WINDROWS IS NOT NECESSARY UNLESS RECOMMENDED. ~ IE) CLEAR AREA FOR UTILITY TRENCHES, FOLINDATIONS AND SWIMMING POOLS. (Fl ALL FILL OVER AND AROUND ROCK WINDROW SHALL BE COMPACTED TO 90% . RELATIVE COMPACTION OR AS RECOMMENDED. (Gl AFTER FILL BETWEEN WINDROWS IS PLACED AND COMPACTED WITH THE LIFT OF FILL COVERING WINDROW, WINDROW SHOULD BE PROOF ROLLED WITH A 0-9 DOZER OR EQUIVALENT. VIEWS ARE DIAGRAMMATIC ONLY. ROO< SHOULD NOT TOUCH AND VOIDS SHOULD BE COMPLETELY FILLED IN. PLATE RD-1 •:·· . . . • ROCK DISPOSAL P·ITS VIEWS ARE DIAGRAMMATIC ONLY. ROa< SHOULD NOT TOUCH · AND VOIDS SHOULD BE COMPLETELY FILLED IN. FILL LIFTS COMPACTED OVER ROCK AFTER EMBEDMENT r-----------J l I ,-,-- 1 J -COMPACTED FILL I I I I GRANULAR MATERIAL ------.., SIZE OF EXCAVATION TO BE COMMENSURATE WITH ROCK SIZE I I i I I I ROCK DISPOSAL LAYERS GRA":(ULAR SOiL TO FILL VOIDS,~· FCOM.PACTEO FILL ·oENSIFJEO BY FLOODING --.--------...._ . ,,-. ' LAYER ONE ROCK HIGH o~o~o~ --. ........ _____ ~--------- PROFILE ALONG LAYER FILL SLOPE . . · I CLEAR ZONE 20' MINIMU_M LAYER ONE R.OCK HIGH PLATE RD-2 • B • • •• Geotechnical • Geologic • Environmental 5741 Palmer Way • Carlsbad, California 92008 • (760) 438-3155 • FAX (760) 931-0915 October 16, 2000 W.O. 2929-A-SC Mr. David Bentley 7 449 Magellan Street Carlsbad, California 92009 Subject: Addendum to, "Limited. Geotechnical Evaluation, Holly Springs Project, Carlsbad, San Diego County, California," W.O. 2929-A-SC, dated October 11, 2000, by GeoSoils, Inc, Reference:. "Excavation Handbook,.,McGraw-Hill, Inc., copyright 1981, by Horace K. Church. Dear Mr. Bentley: • : Pursuant to the request of Mr. Ladwig (Ladwig Design Group), GeoSoils, Inc. (GSI) is providing the following preliminary estimate of quantities regarding shrinkage and bulking of earth materials onsite. The information provided herein is based upon our experience in the site vicinity, as well as information provided in the above referenced text. •• The volume change of excavated materials upon compaction as engineered fill is anticipated to vary with material type and location. Tentatively, overall earthwork shrinkage and bulking may be approximated by using the following parameters: TopsQil/Colluvium .......... , . . . . . . . . . . . . . • . . . . . . . . . . . . . ±3% to 8% shrinkage Alluvium .............................................. ±8% to 12% shrinkage Santiago Formation ............................... ±2% to 3% shrinkage or bulk Rock (excavated) . . . . . . . . . . . . . . . . . . . . . . . . . • . . . . . . . . . . . . . . . . ±5% to 10% Bulk Rock (Shot) .............. .-. . . . . . . • . . . . . . . . . . . . . . . . . . . . . . . ± 15% to 20% Bulk It should be noted that the above factors are estimates only, based on preliminary data. In the case of "shot rock," the percentage of bulking increases with the depth of cut. Final earthwork balance factors could vary. In t_hjs regard, it is recommended that balance areas be reserved where gr~des could be adjusted up or down near -the completion of grading in order to accommodate any yardage imbalance for the project. Consideration should be given to ·completing· grading in cut areas where granitic and/or volcanic bedrock is exposed onsite, to allow for maximum rock and/or rock-fill placement/burial. • Distribution: (1) Addressee (4) Ladwig Design Group, Attention: Mr. Bob Ladwig Mr. David Bentley Holly Springs Project File:e:\wp7\2900\2929a.atl W.o: 2929-A-SC October i 6, 2000 Page2