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Home My WebLink AboutMS 16-05; 1284 PINE AVE; GEOTECHNICAL UPDATE REPORT; 2019-11-05MS 16-05 C ,. .. • Ill • .. .. • • • • • .. .. .. Ill 11111 .. -• .. • .. .. • • • • .. • -.. L. W. C. HOBBS, CONSUL TING ENGINEER 33892 COPPER LANTERN, UNIT A DANA POINT CALIFORNIA 92629 (951) 660-9800 Date: November 5, 2019 Project No: 19014-1 1284 Pine Partners, LLC 1284 Pine Avenue Carlsbad, California 92008 Subject: Geotechnical Update Report with References, As-Graded Conditions, 1284 Pine Avenue, Carlsbad, California 92008 Gentlemen,. This letter report has been prepared to revise the previous letter report of same subject dated June 6, 2019 by including all referenced materials to assist in clarification. Onsite observation and review confirms that the subject site has been graded and remains in substantial conformance to the lines and grades and compaction as recommended in the included referenced reports. Referenced reports are included herewith in Appendices in date order, most recent to oldest. The opportunity to be of service is appreciated. Should questions or comments arise pertaining to this document, or if we may be of further service, please do not hesitate to call our office. Bill Hobbs, RCE 42265 Civil Engineer Distribution: Addressee (1) electronic pdf Attachments: Appendix A, Foundation Plan Review, June 21, 2019 Appendix B, Geotechnical Update, June 6, 2019 RECEIVED DEC O 4 2019 !_AND DEVELOPMENT ENGINEERING Appendix C, Revised Seismic Design Parameters, April 9, 2019 Appendix D, Certification of Pad (Compaction Report), May 9, 2016 Appendix E, Geotechnical Update, May 27, 2015 Appendix F, Preliminary Geotechnical, (Update) Sept. 5, 2013 Appendix G, Preliminary Geotechnical Investigation, Sept. 20, 2012 .. ii. C C C Ill 1111 Ill 1111 • .. • • • • • • Ill • • • • • • .. APPENDIX A FOUNDATION PLAN REVIEW JUNE 21, 2019 W. C. HOBBS, CONSULTING ENGINEER .. .. .. • .. • .. .. Ill .. .. .. • • Ill • • • .. .. • • • .. ,. I 111111 W. C. HOBBS, CONSUL TING ENGINEER 33892 COPPER LANTERN, UNIT A DANA POINT CALIFORNIA 92629 (951) 660-9800 Date: June 20, 2019 1284 Pine Partners, LLC 1284 Pine Avenue Carlsbad, California 92008 Subject: Foundation Plan Review, Proposed Residence, 1284 Pine Avenue, Carlsbad, California 92008 Attention: City of Carlsbad Building Official This letter has been prepared to indicate that the foundation plan and associated details for the proposed residence at the subject site have been reviewed and found to be in compliance with the minimum recommendations contained in the referenced report(s) . Additionally, as recommended in the reference, footing excavations shall be observed by the soil engineer prior to placement of construction materials in them . The opportunity to be of service is appreciated. Should questions or comments arise pertaining to this document, or if we may be of further service, please do not hesitate to call our office . Respectfully Submitted, W. C. HOBBS, CONSULTING ENGINEER ----- ' ' I -i/-,' ~ /_/y Bill Hobbs, RCE 42265 I ' dr Civil Engineer /~ / \, /.),.' 1/ J \ \ 1/,,'F , ~---~\,:' _1/ F c,,\.\_ , -···· -- Distribution: Addressee (1) pdf electronic Attachments: None Reference: Certification of Pad, Proposed 2nd Dwelling, APN 205-020-04, Lot 9 of Tract Map No 1744, 1284 Pine Avenue, City of Carlsbad, San Diego County, California, by South Shore Testing & Environmental, WO 1931503.00U, May 9, 2016 and Update dated June 6, 2019 by W. C. Hobbs, Consulting Engineer, Project No: 19014-1. .. 1111 .. • ,. • • • • • (11111111 L. C .. ... -• -• ---• -11111 ... .. APPENDIX B GEOTECHNICAL UPDATE LETTER JUNE 6, 2019 W. C. HOBBS, CONSULTING ENGINEER ,. .. C r 6i. C .. I .. ... I.. • .. • • • • • • • • • • • • W. C. HOBBS, CONSUL TING ENGINEER 33892 COPPER LANTERN, UNIT A DANA POINT CALIFORNIA 92629 (951) 660-9800 Date: June 6, 2019 Project No: 19014-1 1284 Pine Partners, LLC 1284 Pine Avenue Carlsbad, California 92008 Subject: Geotechnical Update, As-Graded Conditions, 1284 Pine Avenue, Carlsbad, California 92008 This letter report has been prepared to indicate that onsite observations and review confirms that the subject site has been graded and remains in substantial conformance to the lines and grades and compaction as completed pursuant to the referenced report. The building project may proceed at this time without further grading requirements . The opportunity to be of service is appreciated. Should questions or comments arise pertaining to this document, or if we may be of further service, please do not hesitate to call our office. Respectfully Submitted, W. C. HOBBS, CONSUL TING ENGINEER ... ~. "' \r." 1" I "<) .r::;r-,~ } I , \ . . :t• . \,: Q \ ,'....._T / ',.f'/'""-( 1\\';/4-1-/ ',,_:r£ofl:.~ \ \~ BilU:-lobbs, RCE 42' - Civil Engineer Distribution: Addressee (1) pdf Attachments: None Reference: Certification of Pad, Proposed 2nd Dwelling, APN 205-020-04, Lot 9 of Tract Map No 1744, 1284 Pine Avenue, City of Carlsbad, San Diego County, California, by South Shore Testing & Environmental, WO 1931503.00U, May 9, 2016 Ill .. C r .. C C .. L. C C ,.. L. ,.. L. 1111 .. • • • • • • • • • .. APPENDIX C REVISED SEISMIC DESIGN PARAMETERS APRIL 9, 2019 W. C. HOBBS, CONSULTING ENGINEER C C ,.. 1 ... r .. r .. .. • ... ,.. L. .. .. .. -• -• -.. .. ... W. C. HOBBS, CONSUL TING ENGINEER 33892 COPPER LANTERN, UNIT A DANA POINT CALIFORNIA 92629 {951) 660-9800 Date: April 9, 2019 1284 Pine Partners, LLC 1284 Pine Avenue Carlsbad, California 92008 Subject: Revised Seismic Design Parameters, Proposed 2nd Dwelling, 1284 Pine Avenue, Carlsbad, California 92008 This letter report has been prepared to revised design seismic parameters to comply with 2016 California Building Code(s) and ASCE/SEI 7-16. These parameters are based on site geographic location, Soil Class D criteria and Risk Category II. The opportunity to be of service is appreciated. Should questions or comments arise pertaining to this document, or if we may be of further service, please do not hesitate to call our office . Respectfully Submitted, W. C. HOBBS, CONSULTING ENGINEER "l.-/c \ ! I /< '• /*/ \ \ l'"y \ J',''-.._ ( I\ \ \, {, .. ~'_, -, r-r" ' -1 -.,__ ; ,,/4 ~ / Bill Hobbs, Fyac 42265 ~ ,_?_~;:~-~\, \ ~ - Civil Engirreer Distribution: Addressee (1) pdf Attachments: Seismic Report from ASCE, 2 pages Reference: Geotechnical Update, Proposed 2nd Dwelling, APN 205-020-04, Lot 9 of Tract Map No 1744, 1284 Pine Avenue, City of Carlsbad, San Diego County, California, by South Shore Testing & Environmental, WO 19~31503.00U, May 27, 2015 ASCE. AMERICAN SOCIElY Of CML ENGINEE!IS Address: 1284 Pine Ave Carlsbad, California 92008 https ://a see 7hazardtool .online/ ASCE 7 Hazards Report Standard: ASCE/SEI 7-16 Risk Category: 11 Soil Class: D -Stiff Soil Page 1 of 3 Elevation: 108.33 ft (NAVO 88) Latitude: 33.162077 Longitude: -117.338808 Tue Apr 09 2019 -----------.. AMERICAN SOCIETY OF CML ENGINEERS Seismic Site Soil Class: Results: Ss S1 Fa Fv SMs SM1 D -Stiff Soil 1.053 0.382 1.079 N/A 1.136 N/A So1 N/A TL : 8 PGA: 0.463 PGAM: 0.527 FPGA 1.137 le 1 -Sos 0.757 Cv : 1.311 • Ground motion hazard analysis may be required. See ASCE/SEI 7-16 Section 11.4.8. -.. -----------• -• -----.. Data Accessed: Tue Apr 09 2019 Date Source: USGS Seismic Design Maps https://asce 7hazardtool .online/ Page 2 of 3 Tue Apr 09 2019 -------- ---------------------------• • ASCE. AMERICAN SOCIETY Of CML ENGINEERS The ASCE 7 Hazard Tool is provided for your convenience, for informational purposes only, and is provided "as is" and without warranties of any kind. The location data included herein has been obtained from information developed, produced, and maintained by third party providers; or has been extrapolated from maps incorporated in the ASCE 7 standard. While ASCE has made every effort to use data obtained from reliable sources or methodologies, ASCE does not make any representations or warranties as to the accuracy, completeness, reliability, currency, or quality of any data provided herein. Any third-party links provided by this Tool should not be construed as an endorsement, affiliation, relationship, or sponsorship of such third-party content by or from ASCE. ASCE does not intend, nor should anyone interpret, the results provided by this Tool to replace the sound judgment of a competent professional, having knowledge and experience in the appropriate field(s) of practice, nor to substitute for the standard of care required of such professionals in interpreting and applying the contents of this Tool or the ASCE 7 standard. In using this Tool, you expressly assume all risks associated with your use. Under no circumstances shall ASCE or its officers, directors, employees, members, affiliates, or agents be liable to you or any other person for any direct, indirect, special, incidental, or consequential damages arising from or related to your use of, or reliance on, the Tool or any information obtained therein. To the fullest extent permitted by law, you agree to release and hold harmless ASCE from any and all liability of any nature arising out of or resulting from any use of data provided by the ASCE 7 Hazard Tool. https://asce 7hazardtool .online/ Page 3 of 3 Tue Apr 09 2019 ------------------------- - -.. ---- APPENDIX D CERTIFICATION OF PAD (COMPACTION REPORT) MAY 9, 2016 W. C. HOBBS, CONSULTING ENGINEER --------.. -.. -----------------• ---- South Shore Testing & Environ~ental 23811 Washington Ave, Suite Cl 10, #I 12, Murrieta, CA 92562 Phone: (951) 239-3008 FAX: (951) 239-3122 May 9, 2016 1284 Pine Partners, LLC Clo Mr. David Fiscbach 1284 Pine Avenue Carlsbad, California 92008 SUBJECT: CERTIFICATION OF PAD Proposed 2ND Dwelling APN: 205-020-04, Lot 9 of Tract Map No 1744 1284 Pine A venue City of Carlsbad, San Diego County, California Work Order No. 1931503.22 Dear Mr. Fiscbach: E-mail: ss.testing@aoLcorn In accordance with your request, we have prepared this "Certification of Pad" report presenting the results of our testing of the proposed Single Family Residence at the above referenced site. A 10- scale "Grading Plan" prepared by Kevin P. Bresnahan of Fallbrook, California, was provided for our use and utilized to locate our field density tests. A not-to-scale copy of the 10-scale plan was utilized as a base map for our Compaction Test Location Map presented as Plate l. The subject site had been previously been rough graded under the observation and testing of another soils engineering firm ESI of Temecula, California who had also perforn1ed a preliminary geotechnical investigation (2013) for the subject site. It is our understanding that ESI is no longer conducting business and records of the previous testing was not available. South Shore Testing and Environmental became the Engineer of Record for the subject site on May 1, 2015. We have reviewed and accepted the referenced geotechnical report as being prepared in accordance with current industry standards and guidelines at the time of its preparation. South Shore Testing and Environmental became the Engineer of Record for the subject site on May 1, 2015 and prepared a geotechnical update (South Shore, 2015) for the subject site. We have reviewed and accepted the referenced geotechnical report as being prepared in accordance with current industry standards and guidelines at the time of its preparation. Scope of Work The scope of work performed for this report included the following: 1. Onsite observation and documentation of existing site geometry and grading that has taken place with respect to the existing residential pad SOUTH SHORE TESTING & ENVIRONMENTAL Work Order No. 1931503.22 --------------•--·.,·-----------------. . . ·-·---------- -- -------------------------------.. .. 1284 Pine Paiiners, LLC Clo Mr. David Fiscbach May 9, 2016 Page 2 2. Compilation of data obtained from laboratory testing. 3. Subsurface exploration and compilation of data obtained from field observations and in- place density testing of the existing fill. 4. Preparation of this certification report containing the results of laboratory and field testing, engineering analyses, and final foundation design minimums. Executive Summary This report has been prepared partially resulting from a 2013 California Building Code Chapter 18 requirement for geotechnical investigation being conducted for all projects in Seismic Category D. This rep011 will address geotechnical conditions existing on the site as they pertain to final foundation design minimums for the proposed 2ND residence that will be constructed on southerly portion of the subject site adjacent to Pine Avenue. We anticipate that construction will consist of typical slab-on-grade construction with continuous and isolated footings. Site Description The subject site consists of a rectangular--shaped parcel of land located on the northerly side of Pine A venue (1284) in the City of Cai·lsbad, San Diego County, California. The site is located in an area of predominately residential properties. The previous residential structure on the subject site has been demolished and disposed of offsite and another single-family residence built on the northerly portion of the site. Overall relief on the subject site is approximately 5-ft, from above mean sea elevations l 06 to 1 I 1. SUMMARY OF EARTHWORK General Contained herein are the results of compaction testing and observations made during subsurface investigation of the existing rough graded residential fill pad at the subject site. Test locations are plotted on the Geotechnical Map, Plate 1, attached to this report. The results of laboratory and field density testing are contained in the attached Appendixes B & C, respectively. In-place density testing was conducted on April 29, 2016. A Bobcat excavator was provided to excavate three holes for our subsurface investigation and density testing was performed at varying depths. Our in-place density tests obtained consistent test results all of which were a minimum of 90 percent of the dry density as determined by ASTM D 1557 test method. The upper 1-ft of the existing fill pad appears to have dried back since the completion of grading and prior to excavation of footings, should be processed consisting of scarifying the upper 12-inches of the pad surface, moisture conditioning to near optimum moisture content, and re-compacting to a minimum of90 percent of the dry density as determined by ASTM D 1557 test method. SOUTH SHORE TESTING & ENVIRONMENTAL Work Order No. 193 I 503.22 -------------"•-------------------·-----· RETAINING WALL KEY EXTENSION DETAIL - SCALE: V2"•1' HORZ, 1/2'•T VERT. tM;ll-'11 .. t"UUWlU. ~~:~}~{c _____ _ AAOl,l<,'l:•·rt.111 DHU, =,u,=,00,--\1··• l't:ll.,.!,<-t1100T, ::-::.;~•O(lnt, \. :~;:!;';~{t~\ ~.,H(,,...-,..o..c.,.~ l --;;~?' ,t,-,':. ,:?i Nern:, si:.c u:lTCR or PCRMISSION DAT(ij JA!-1. 4 20!6 tr Ai!MANOO l 00AA OANNA ?fRMIITHGG.qADINGFDRVALlC()ISTRUCTlDHorr-sm. c}/ 'i§• ':i = ~~:~stl,f ~0~~::i •~. ~{ 'F-=-a;.;;;a-aaj;s:a.;aat;:a;:.""'aaaaaaaa=~.;,J;,;.;.,,a;aaaa.i.;c1-=a;::~;,aaea.i~';-l~ ' :~\t· /-~\[ ·~ 11' • • ''"' 01 I ,,,., --...____ ,/ ., ' ;;;----Ii--<-; 4_,.·•.:f-' :1!~~v.1 ' :)O"~ .... -' 3~ ,!I · ·''·--·=,--~-_--,-_--·-----~ ..._-'"'' o,';;l;'·t > .,,J • . _i( :;.:.:.1,'.:-· NT(~INC~ ,,!) : ,..-~ ~'i ~ 1•1 '": ·'/\..;,('.y I l~ :,, -orw l'?rl l sy,\ ~ : ' ..,.__ I . /~ fOR WALL O(SIGN ONLY" ~-::c~S:1 J • , J;----OS.:::----c::. ;.---! -,-------W ,,..,,.--__,.,-' ~~'";fJ~~;,r"' .,t.~•Vi•~ -; Ft-=--/--, __ "_ _ _:_::,_=_,.C~~-':...'"'-----=---~ /!).~~-I :5•· t-:, TYPiCAL SECTION PiNtA~E ; !f '\ . 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I/ )-;,e5 SECTION A3_-,-"d' SOUTH SHORE TESTING & ENVIRONMENTAL COMPACTION TEST LOCATION MAP PH.OPOSED 2·"0 DWELLING APN 205-020-04, I.OT 9 OF TRACT MAP NO. l 744 121'14 PINI~ A VENUE c,·rv OF CARI.SHAD, SAN DIF.CO COUNTY, CALIFOl~NIA wonK ORl)ER; J9Jl503.22 DATE: MAY 2016 PLATE:JJ2£.l ®-APPROXIMATE LOCATION OP COMPACTION TESTS GRAPHIC SCALE ~"'~ lk.-..-J.J..Ji I il~=~)ll .,.....,,,,I '·+---!.il=·--PLAN / -,' c;' '\ E, "i '\ I , __ ,-----L _:_,·J•:":·,_J r--~ _.,.,_,,.~ . .,q.:• ,,,n----1 ENGINEER OF WORK -----·--.... ~; •!.'"' ~.,t>ts·v.•<.\., ;[~~~-7/!~F;-~"~ I :~~•: ~J.• ~YI ~---:·1,-,.,,:;,:_..,,, RE ... SlON OESCR1Pn0tt "AS BUil T' "'--£JP.__ OA<C lt[Vl[IJ[tl IY• !NSPCCTOR ~ f1-mi CITY OF CARLSBAD r="l l__!j (Hu!t.CCRI~ OCPAIH..:[NT L...!_j ,GRAOU«. P'.Ji.►-S nllt 1284 PINE AVENUE APPRO-..CO;,MSCiNS.G{LOERT Cl1l (NOl([R Pf &ll12 ~lPIIICS 9/Yl{I' °"IE ~1 """"""' 11""""" "'J ~ PD15--01 486-3A - -----------... --.. .. --------- .. ... .. ----- 1284 Pine Partners, LLC Clo Mr. David Fiscbach May 5, 2016 Page 3 Based on our review of the previous geotechnical report (ESI, 2012) and subsurface investigation, the proposed building pad was overexcavated a minimum of 3.5-ft below the original ground surface and extended a minimum of 5-ft outside the building pad. Field density testing was conducted in accordance with ASTM test designation D 6938-06el (nuclear gauge) for every 2 vertical feet of fill placement. All earth materials utilized in creating the pad were tested for maximum density and expansion characteristics during and after grading. A total of 8 field density tests were conducted during subsurface exploration of the existing rough graded fill pad. Density test results are contained in Appendix C and the approximate locations are shown on enclosed Plate 1, Geotechnical Map (attached) Laboratory Testing Testing of recovered soil samples (representative of the area) consisted of laboratory maximum density test (ASTM D 1557-12) and Expansion index (ASTM D 4829-11 ). The results of laboratory testing are indicated in Appendix B. CONCLUSIONS AND RECOMMENDATIONS Conclusions General The development of the site as proposed is both feasible and safe from a geotechnical standpoint provided that the recommendations contained herein are implemented during design and construction. The overall recommendations are presented herein. 1. 2. 3. According to the available grading plan, the proposed residence will be constructed on the southerly portion of the subject site adjacent to Pine Avenue. Observation, classification, and testing indicate that the near surface soils are non- expansive (Expansion Index ;520 -2013 CBC, Section 1803.5.3) with an El of 5 consisting of a fine silty Sand (SM) . Fill slopes were constructed at a 2.5:l (h:v) slope ratio in accordance with the 2013 CBC and current City of Oceanside guidelines, to a maximum height of approximately 3-ft, and are anticipated to be surficially and grossly stable . SOUTH SHORE TESTING & ENVIRONMENTAL Work Order No. 1931503.22 -• -.. .. .. .. .. -• -• --.. .. -.. .. .. .. 11111 .. ... .. .. -• ---• ---.. .. 1284 Pine Partners, LLC Clo Mr. David Fiscbach May 5, 2016 Page4 4 . Our in-place density tests obtained consistent test results all of which were a minimum of 90 percent of the dry density as determined by ASTM D 1557 test method. The upper 1- ft of the existing fill pad appears to have dried back since the completion of grading and prior to excavation of footings, should be processed consisting of scarifying the upper 12- inches of the pad surface, moisture conditioning to near optimum moisture content, and re-compacting to a minimum of 90 percent of the dry density as determined by ASTM D 1557 test method. Recommendations General It is our understanding that no preliminary geotechnical report was available for the subject site. The recommendations contained in herein are based on our testing recommendations during grading . Allowable Safe Bearing Capacity An allowable safe bearing capacity of 1,500 pounds per square foot (psf) may be used for design of continuous footings that maintain a minimum width of 12-inches and a minimum depth of at least 12-inches below the lowest adjacent grade. The bearing value may be increased by 10% for each additional foot of depth and/or width to a maximum of 2,300 psf The bearing value may be increased by one-third for seismic or other temporary loads . Settlement The bearing value recommended above reflects a total settlement of 0.5'' and a differential settlement of 0.5'' within a horizontal distance of 10 feet (L/240). Most of this settlement is expected to occur during construction and as the loads are being applied. Lateral Load Resistance The bearing value of the soil may be increased by one third for short duration loading (wind, seismic). Lateral loads may be resisted by passive forces developed along the sides of concrete footings or by friction along the bottom of concrete footings. The value of the passive resistance for level ground may be computed using an equivalent fluid density of 300 pcf for level ground . The total force should not exceed 3,000 psf. A coefficient of friction of .35 may be used for the horizontal soil/concrete interface for resistance of lateral forces. If friction and passive forces are combined, then the passive values should be reduced by one third. SOUTH SHORE TESTING & ENVIRONMENTAL Work Order No. 1931503.22 .. .. .. 1111 .. ... .. ... .. -... .. ... ... ,,.. ... .. ... --.. .. ... -.. ----------- 1284 Pine Partners, LLC Clo Mr. David Fiscbach May 5, 2016 Page 5 Foundation System Design Foundation elements for the proposed structures should be founded entirely in compacted engineered fill materials. South Shore Testing & Environmental should perform a footing inspection, prior to placement of reinforcement to insure the footing excavations and reinforcement have been constructed in accordance with the recommendations presented in this report . For single-story or equivalent strnctures, continuous spread footings should be a minimum of 12- inches wide and 12-inches below the lowest adjacent grade. For two-story or equivalent structures, continuous spread footings should be a minimum of 15-inches wide and 18-inches below the lowest adjacent grade. As a minimum, all footings should have one No. 4 reinforcing bar placed at the top and bottom of the footing. In no case should the content of steel in concrete footings be less than the recommended minimums of the appropriate sections of the A.C.l. standards . Concrete Slabs All concrete slabs on grade should be 5-inches thick, minimum. They should be underlain by 2 inches of sand or approved non expansive onsite materials. Imported materials should be utilized for this purpose. Contractors should be advised that when pouring during hot or windy weather conditions, they should provide large slabs with sufficiently deep weakened plane joints to inhibit the development of irregular or unsightly cracks. Also, 5-inch thick slabs should be jointed in panels not exceeding 8 feet in both directions to augment proper crack direction and development. The slab area and footing excavations and any concrete flatwork should be pre- moistened to prior to placement of concrete . Moisture Barrier When the intrusion of moisture through concrete slabs is objectionable, particularly with interior slabs where flooring is moisture sensitive, a vapor barrier should be installed onto the subgrade prior to the pouring of concrete. Concrete slabs, in moisture sensitive areas, should be underlain with a vapor barrier consisting of a minimum of 10.0-mil polyvinyl chloride membrane with all laps sealed. A 2-inch layer of clean sand should be placed above the moisture barrier. The 2-inches of clean sand are recommended to protect the visqueen moisture barrier and aid in the curing of the concrete. The project architect and or structural engineer may recommend alternative devices for moisture protection. Slab Reinforcement From a Geotechnical standpoint, slabs should be reinforced with a minimum of number 3 steel bars placed at the center of thickness at 24-inch centers both ways. These are considered minimums and additional requirements may be imposed by other structural engineering design requirements. SOUTH SHORE TESTING & ENVIRONMENTAL Work Order No. 1931503.22 .. --.. .. -.. .. .. .. -.. .. ... .. ... 11111 .. .. .. .. ... ... .. .. -.. ---------- 1284 Pine Partners, LLC Clo Mr. David Fiscbach May 5, 2016 Page6 Concrete Based on the previous testing of the onsite soils for soluble sulfate content testing, it is anticipated that, from a corrosivity standpoint, Type II Portland Cement can be used for construction. Previous test results (ESI, 2013) indicated that the percentage by weight of soluble sulfates of the onsite soils as 0.0125, which equates to a Negligible sulfate exposure per American Concrete Institute (ACI), 318, Table 4.3 .1 (2005). Observation of F'oundation Excavations In accordance with the 2013 CBC and prior to the placement of forms, concrete, or steel, all foundation excavations should be observed by the geologist, engineer, or his representative to verify that they have been excavated into competent bearing materials. The excavations should be per the approved plans, moistened, cleaned of all loose materials, trimmed neat, level, and square. Any moisture softened earth materials should be removed prior to steel or concrete placement. Earth materials from foundation excavations should not be placed in slab on grade areas unless the materials are tested for expansion potential and compacted to a minimum of 90 percent of the maximum dry density . Fine Grading and Site Drainage Fine grading of areas outside of the proposed structures should be accomplished such that positive drainage exists away from all footings in accordance with 2013 CBC and local governing agency requirements. Run-off should be conducted in a non-erosive manner toward approved drainage devices per approved plans. No run-off should be allowed to concentrate and flow over the tops of slopes. Post Earthwork Construction South Shore Testing & Environmental, or a duly designated representative, should be present to test and or confirm the conditions encountered during site development. In addition, post earthwork construction monitoring should be conducted at the following stages: • Moisture content near optimum will necessarily need to be maintained, both to maintain proper compaction and to prevent wind erosion of the pad. SOUTH SHORE TESTING & ENVIRONMENTAL Work Order No. 1931503.22 -------.. --.. .. .. .. ... ... .. .. ---.. ... -.. ------------ 1284 Pine Pat1ners, LLC Clo Mr. David Fiscbach May 5, 2016 Page 7 • At the completion of foundation excavations, but prior to the placement of steel and or other construction materials in them. As a requirement of this report, the undersigned must, in writing, ce11ify that the foundations meet the minimum requirements of this report and the building plans for depth and width along with the earth materials being the appropriate moisture content and compaction. Backfilling of over deepened footings with earth materials will not be allowed and must be poured with concrete. Consequential changes and differences may exist throughout the earth materials on the site. It may be possible that ce11ain excavations may have to be deepened slightly if ea11h materials are found to be loose or weak during these observations . • Any other pertinent post construction activity where soils are excavated or manipulated or relied upon in any way for the performance of buildings or hardscape features. This would necessarily include preparation of exterior slab subgrades • Cuts to 5 feet, or slightly more will stand vertical for normal time periods associated with construction of retaining walls. Time periods for unsupported cuts 5 feet or greater vertical should be limited to 60 days in the non-rainy season and 30 days in the rainy season. Construction Monitoring: Summary These supplemental services are necessary and required during project development and construction. They are summarized here as follows: • Foundation plan review. • Observation of foundation excavations prior to placement of forms and construction materials. • During the placement of utility trench backfill • During preparation of subgrades for hardscape and concrete flatwork. • At any time when earth materials are manipulated and or relied upon for the support of structural loads or within the vicinity of where structural loads are already applied to soils. SOUTH SIIORE TESTING & ENVIRONMENTAL Work Order No. I 931503.22 .. .. .. .. ---.. -----------... .. -.. -------.. -.. ---- 1284 Pine Partners, LLC Clo Mr. David Fiscbach May 5, 2016 Page 8 LIMITATIONS Our professional services were performed using the degree of care and skill ordinarily exercised, under similar circumstances, by reputable Geotechnical Engineers and Geologists practicing in this or similar localities. No other warranty, expressed or implied, is made as to the conclusions and professional advice included in this report. This report is issued with the understanding that it is used only by the owner and it is the sole responsibility of the owner or their representative to ensure that the information and recommendations contained herein are brought to the attention of the architect, engineer, and appropriate jurisdictional agency for the project and incorporated into the plans; and the necessary steps are taken to see that the contractor and subcontractors carry out such recommendations contained herein during construction and in the field. The samples taken and used for testing and the observations made are believed representative; however, soil and geologic conditions can vary significantly between test locations. The evaluation or identification of the potential presence of hazardous or corrosive materials was not part of the scope of services provided by South Shore Testing & Environmental. The findings of this report are valid as of the present date. However, changes in the conditions of a property can occur with the passage of time, whether due to natural processes or the works of man on this or adjacent properties. In addition, changes in applicable or appropriate standards may occur, whether they result from legislation or the broadening of knowledge. Accordingly, the findings of this report may be invalidated wholly or partially by changes outside our control. Therefore, this report is subject to review and revision as changed conditions are identified . The firm that performed the geotechnical services thus far for this project should be retained to provide testing observation services during construction to maintain continuity of geotechnical interpretation and to check that the recommendations presented herein are implemented during site development, excavation of foundations and construction of improvements. If another geotechnical firm is selected to perform the testing and observation services during construction operations, that firm should prepare a letter indicating their intent to assume the responsibilities of project geotechnical engineer of record. Selection of another firm to perform any of the recommended activities or failure to retain the undersigned to perform the recommended activities wholly absolves South Shore Testing & Environmental, the undersigned, and its assigns from any and all liability arising directly or indirectly from any aspects of this project. SOUTH SHORE TESTING & ENVIRONMENTAL Work Order No. l 931503 .22 .. .. - --------.. ... ... .. ----.. ---------------- 1284 Pine Partners, LLC Clo Mr. David Fiscbach May 5, 2016 Page 9 CLOSURE The opportunity to be of service is appreciated. Should questions or comments arise pertaining to this document, or if we may be of further service, please do not hesitate to call our office. Respectfully Submitted, South Shore Testing and Environmental /) I ,, ·\ /-{_,-J ' P. Frey il PJ ~ ct Manager I ATTACHMENTS Plate l -Compaction Test Location Map (reduced l 0-Scale) Appendix A -References Appendix B -Laboratory Test Results Appendix C -Results of Compaction Tests SOUTH SHORE TESTING & ENVIRONMENTAL d!{;o vt /44,,"0 /$,/' .,.. __ William C. Hobbs, RCE 42265 Civil Engineer Work Order No. 1931503.22 --------.. ---.. ------- -----• -• ---• ---- APPENDIX A References SOUTH SHORE TESTING & ENVIRONMENTAL Work Order No. 1931503.22 ---------------------... ---------------- REFERENCES Bresnahan, Kevin, P.E., Undated, "Precise Grading Plan -829 South Pacific Street Condominiums", Sheets 1 & 2 of 2, Scale: I"= 8'. California Building Standards Commission (CBSC), 2013, "2013 California Building Code, California Code of Regulations, Title 24, Part 2, Volume 2 of2". California Division of Mines & Geology, 1997, "Guidelines for Evaluating and Mitigating Seismic Hazards in California", Special Publication 117. California Division of Mines & Geology, 1996, "Probabilistic Seismic Hazard Assessment for the State of California", OMO Open File Report 96-08, USGS Open File Report 96-706. City of Carlsbad, Revised August 2010, "Retaining Wall B-7" Sheets 1 & 2 of 2. Coduto, Don, P., 1994, "Foundation Design Principles and Practice", Prentice Hall, pages 637-655. ESI, 2013, "Preliminary Geotechnical Investigation, Two Residential Lots -TPM MS I 3-03, 0.26 +/-Acres, Lot 9, PM 1744, APN 205-020-04, 1284 Pine Avenue, Carlsbad, California", Project No, 12-0808-PL, Dated September 5, 2013. Hait, E.W., 2000, "Fault-Rupture Hazard Zones in California", California Division of Mines and Geology Special Publication 42, CD-003 (CD-ROM Version). Houston, S. L., 1992, "Partial Wetting Collapse Predictions", Proceedings of the 7th International Conference on Expansive Soils, Vol. I, pages 302-306. Kennedy, M.P., & Tan, Siang S., 2005, "Geologic Map of the Oceanside 30 x 60 Quadrangle, San Diego County, California", California Geological Survey Regional Geologic Map, Scale: I" = 100,000-ft. Petersen, M., Beeby, D., Bryant, W., Cao, C., Cramer, C., Davis, J., Reichle, M., Saucedo, G., Tan, S., Taylor, G., Toppozada, T., Treiman, J., and Wills, C., 1999, Seismic Shaking Hazard Maps of California", California Division of Mines and Geology Map Sheet 48, varied scales. Proceedings of the 7th International Conforence on Expansive Soils, Volume I, "Foundations on Hydro-collapsible Soils, Pages 256-261. San Diego Regional Standard Drawing, August 2009, "Drawing Number C-7". State of California Water Quality Control Board Website, 2016, "Groundwater Information and Geotracker Site Information. Weber, Harold F., Jr., 1963, "Geology & Mineral Resources of San Diego County, California". California Division of Mines and Geology County Report 3, Scale" 1""" 10,560-ft. SOUTH SI !ORE TESTING & ENVJRONMENTAL Work Order No. 1931503.22 ----.. --- ... .. ... ... ... ... ... .. -.. -... -.... -------------- APPENDIXB Laboratory Test Results SOUTH SHORE TESTINCi & ENVIRONMENTAL Work Order No. 1931503.22 .. -.. .. .. .. ---------------.. -.. .. ------------ TABLE I Maximum Density/Optimum Moisture % DescriRtion Lbs/Ft3 Moisture I Dark Orange Brown Silty Sand (SM) 118.7 13.9 2 Pale Brown Medium Grained Silty Sand 122.3 9.7 TABLE II EXPANSION INDEX TEST LOCATION EXPANSION INDEX EXPANSION POTENTIAL Pad Surface O to 3' 5 Non Expansive --··---... SOUTH SHORE TESTING & ENVIRONMENTAL WorkOrderNo.1931503.22 -.. .. .. -... .. ... -• -• -----.. -.. .. ... -.. -----------• APPENDIXC Results of Compaction Tests SOUTH SHORE TESTING & ENVIRONMENTAL Work Order No. 193 I 503.22 -----.. ----• ----- -.. ... .. ... .. - ... -------.. .. ... TABLE I RESULTS OF COMPACTION TESTS Job No.: 1931503.22 Name: 1284 Pine Partners-1284 Pine Avenue Date: May 2016 Test Test Elevation Moisture Unit Dry Relative Soil Test Location No. Date Depth Content Density Compaction Type Sec Plate 1 (Feet) (%) (PCF) (%) l 4/29/16 105 11.3 112.6 92N 2 SWC of Pad 2 " FG 7.5 115.8 95N 2 It 3 " 105 7.3 113.3 93N 2 Northerly Side 4 It 106 8.3 112.5 92N 2 It 5 It FG 7.0 116.1 95N 2 II 6 II 105 8.5 113.9 93N 2 SEC of Pad 7 " 106 8.6 116.6 95N 2 " 8 ti FG 6.9 117.3 96N 2 II SEE PLAN FOR TEST LOCATIONS SC -Sand Cone ASTM 01556-64; DC-Drive Cylinder ASTM D2937-71; N-Nuclear ASTM 6938-06e1; NG-Natural Ground+ 85% = Passing Test **TEST FAILED, SEE RETEST SOUTH SIIORE TESTING & ENVIRONMENTAL Work Order No. l 931503.22 .. --.. .. .. .. -------------... ... .. .. ... .. -- -----.. -- APPENDIX E GEOTECHNICAL UPDATE REPORT MAY 27, 2015 W. C. HOBBS, CONSUL TING ENGINEER -.. ---.. ----.. .. ... -.... .. .. .. .. .. .. -.. .. ------------ South Shore Testing & Environmental 23811 Washington Ave, Suite Cl 10, #112, Murrieta, CA 92562 Phone: (951) 239-3008 FAX: (951) 239-3122 May 27, 2015 1284 Pine Partners, LLC 1284 Pine A venue Carlsbad, California 92008 SUBJECT: GEOTECHNICAL UPDATE Proposed 2ND Dwelling APN: 205-020-04, Lot 9 of Tract Map No 1744 1284 Pine A venue City of Carlsbad, San Diego County, California Work Order No. 1931503.00U Dear 1284 Pine Partners, LLC: E-mail: ss.testing@aol.com In accordance with your request, we have performed an update to the referenced "Preliminary Geotechnical Report" (ESI, 2013) for the above referenced subject site located in the City of Carlsbad, California. It is our understanding that a 2ND dwelling was constructed on the northerly portion of the site and the former residence on the southerly portion of the site was demolished and subsequently disposed of offsite. The subject site is currently vacant and undeveloped. The purpose of our investigation was to update the engineering parameters of the onsite soils to current City of Carlsbad standards and the 2013 California Building Code (CBC). South Shore Testing and Environmental became the Engineer of Record for the subject site on May 1, 2015. We have reviewed and accepted the referenced geotechnical report as being prepared in accordance with current industry standards and guidelines at the time of its preparation. Based on our review of the previous geotechnical report (see References, Appendix A), the updated geotechnical recommendations presented in the following sections should be adhered to during site development. For our update investigation, we were provided with 10-scale "Minor Grading Plan" prepared by Kevin Bresnahan of Fallbrook, California. South Shore Testing & Environmental W.O. NO. 1931503.00U -.. --.. ---------.. ----.. -------------• -- 1284 Pine Partners, LLC May 27, 2015 Page2 Proposed Development: SITE CONDITIONS It is our understanding the subject site will be utilized for the construction of a 2ND single-family dwelling on the southerly portion of the site. We anticipate that construction will consist of typical slab-on-grade construction with continuous and isolated footings and retaining walls. Site Description: The subject site consists of a rectangular-shaped parcel of land located on the northerly side of Pine Avenue (1284) in the City of Carlsbad, San Diego County, California. The site is located in an area of predominately residential properties. The subject building pad has been previously developed as a single-family residence that has been demolished and disposed of offsite with minor grading performed to accommodate drainage after demolition. The geographical relationships of the site and surrounding area are shown on our Site Location Map, Figure 1. SUBSURFACE CONDITIONS The subject site is underlain by approximately 3.5-ft of loose to medium dense undifferentiated soil/colluviums overlying dense late to middle Pleistocene-age marine and non-marine terrace deposits (ESI, 2013, Kennedy & Tan, 2007 and Weber, 1963). Groundwater: No groundwater seepage was encountered on the subject site to a depth of 37.6-ft (ESI, 2013) below the ground surface (bgs). The subject site is not located within a recognized groundwater basin (State of California Water Quality Control Board, 2015) and historic high groundwater is anticipated to be at least +50-ft bgs (Geotracker Website, 2015) in the vicinity of the subject site. 2013 CBC SEISMIC PARAMETERS Based on the geologic setting and soil conditions encountered, the soils underlying the site are classified as "Site Class Sc, Very Dense Soils and Soft Rock", according to the 2013 CBC. The seismic parameters according to the 2013 CBC are summarized in the following table. South Shore Testing & Environmental. W.0. No. 1931503.00U -----------------.. --.. --------------... - 1284 Pine Partners, LLC May 27, 2015 Page 3 2013 CBC -Seismic Parameters Mapped Spectral Acceleration Parameters Ss = 1.138 and S1 = 0.437 Site Coefficients Fa = 1.0 and Fv = 1.3 Adjusted Maximum Considered Earthquake SMs = 1.138 and SM1 = 0.595 (MCE) Spectral Response Parameters Design Spectral Acceleration Parameters Sos= 0.759 and Soi= 0.397 The corresponding value for peak ground acceleration from the design response spectrum based on the 2013 CBC seismic parameters is 0.449g. RECOMMENDATIONS Site Clearing: Prior to the commencement of site development, the subject site should be cleared of any vegetation, construction debris, existing walkways, concrete foundations, utility lines, etc., which should be hauled off-site. The client, prior to any site preparation, should arrange and attend a meeting among the grading contractor, the design engineer, the soils engineer and/or geologist, a representative of the appropriate governing authorities as well as any other concerned parties. All parties should be given at least 48 hours notice. Earthwork should be conducted in accordance with the Standard Earthwork and Grading Specifications provided in Appendix B, except where specified in this report. Site Preparation: The proposed structure should be overexcavated to remove all loose undocumented fill and colluvial soils and extend a minimum of 4-ft below the existing ground surface or 2-ft below the bottom of the deepest footing, whichever is deeper. Overexcavation should extend a minimum of 5-ft beyond the building footprint or to a distance equal to the depth of removal, whichever is greater. Removals should extend until medium dense to dense Terrace deposits are exposed throughout the removal. Prior to placement of fill the exposed earth materials should be scarified a minimum depth of 6-in, brought to near optimum moisture content and compacted to 90% relative compaction per ASTM D1557 test method. South Shore Testing & Environmental. W.O. No. 1931503.00U ---------------.. -... .. --.. --------------- 1284 Pine Partners, LLC May 27, 2015 Page4 Fill Placement: Onsite earth materials are expected to be suitable for use as structural fill. A qualified soil engineer should test import materials to determine their feasibility for use as structural fill. Approved fill material should be placed in 6 to 8-inch lifts, brought to at least optimum moisture content, and compacted to a minimum of 90 percent of the maximum laboratory dry density, as determined by the ASTM D 1557 test method. No rocks or chunks of concrete larger than 6 inches in diameter should be used as fill material. No asphalt should be allowed in the fill and if encountered should be disposed properly off site. Rocks larger than 6 inches should either be hauled off-site or crushed and used as fill material or placed in accordance with Appendix B. Expansion Index Testing: Expansion index testing was performed on representative onsite soil sample collected during the previous investigation of the subject site (ESI, 2013). Laboratory test results indicate that the expansion index for the onsite soils is a 0, which is considered Non Expansive (Expansion Index ~20 -2013 CBC, Section 1803.5.3). Expansion testing should also be performed on imported soils prior to their approval as structural fill material and on the pad surface after remedial grading operations to confirm previous testing. Soluble Sulfate Content: Based on the previous testing of the onsite soils for soluble sulfate content testing, it is anticipated that, from a corrosivity standpoint, Type II Portland Cement can be used for construction. Previous test results (ESI, 2013) indicated that the percentage by weight of soluble sulfates of the onsite soils as 0.0125, which equates to a Negligible sulfate exposure per American Concrete Institute (ACI), 318, Table 4.3.1 (2005). Lateral Load Resistance: The following parameters should be considered for lateral loads against permanent structures founded on fill materials compacted to 90 percent of the maximum dry density. Soil engineering parameters for imported soil may vary. Equivalent Fluid Pressure for Level Backfill Active: 48 pcf Passive: 350 pcf Coefficient of friction (concrete on soil): 0.35 South Shore Testing & Environmental. W.O. No. 1931503.00U --.. .. .. ------------.. -... .. .. --.. ------------ 1284 Pine Partners, LLC May 27, 2015 Page5 If passive earth pressure and friction are combined to provide required resistance to lateral forces, the value of the passive pressure should be reduced to two thirds of the above recommendations. These values may be increased by one third when considering short-term loads such as wind or seismic forces. Allowable Safe Bearing Capacity: In competent surficial sediments an allowable safe bearing capacity of 1,500 pounds per square foot (psf) may be used for design of continuous footings that maintain a minimum width of 12-inches and a minimum depth of at least 12-inches below the lowest adjacent grade. The bearing value may be increased by 10% for each additional foot of depth and/or width to a maximum of 2,300 psf. The bearing value may be increased by one-third for seismic or other temporary loads. Total settlements under static loads of footings supported on properly compacted fill materials and sized for the allowable bearing pressures are not expected to exceed 1-inch. Differential settlements between footings designed for the maximum recommended bearing value are expected to be less than one-half of the total settlement. These settlements are expected to occur primarily during construction. Soil engineering parameters for imported soil may vary. Foundation System Design: Foundation elements for any proposed structures should be founded entirely in engineered fill materials. South Shore Testing & Environmental should perform a footing inspection, prior to placement of reinforcement to insure the footing excavations and reinforcement have been constructed in accordance with the recommendations presented in this report. For one-story of equivalent structures, continuous spread footings should be a minimum of 12- inches wide and 12-inches below the lowest adjacent grade. For two-story or equivalent structures, continuous spread footings should be a minimum of 15-inches wide and 18-inches below the lowest adjacent grade. As a minimum, all footings should have one No. 4 reinforcing bar placed at the top and bottom of the footing. The slab area and footing excavations and any concrete flatwork should be pre-moistened to prior to placement of concrete. Concrete slabs, in moisture sensitive areas, should be underlain with a vapor barrier consisting of a minimum of 10.0-mil polyvinyl chloride membrane with all laps sealed. A 2-inch layer of clean sand should be placed above the moisture barrier. The 2-inches of clean sand are recommended to protect the visqueen moisture barrier and aid in the curing of the concrete. The structural engineer should design footings in accordance with the anticipated loads, the soil parameters presented in this limited geotechnical investigation and the existing soil conditions. South Shore Testing & Environmental. W.O. No. 1931503.00U --- ... -----... ... .. ... .. ... .. ... .. .. -.. --.. ------------.. 1284 Pine Partners, LLC May 27, 2015 Page6 Concrete Slabs-On-Grade: Sufficient fine-grained materials exists within near surface earth materials to possible create moisture problems. Therefore, we recommend that a moisture barrier be placed under any concrete slabs that might receive a moisture-sensitive floor covering. This moisture barrier should consist of a IO-mil polyethylene vapor barrier sandwiched between a I-in layer of sand, top and bottom, to prevent puncture of the barrier and enhance curing of the concrete. Reinforcement of the slabs with No. 3 bars on 24-in centers centered in the 5-in slab is recommended. The reinforcing steel should be placed in the upper 1/3 of the slab with at least I-inch of cover. The sub-grade below the slab should be moisture conditioned and properly compacted prior to placement of concrete . Exterior slabs may be placed directly on a properly compacted subgrade consisting of onsite soils or approved imported fill compacted to at least 90 percent relative compaction . The project architect or geotechnical engineer should continually observe all reinforcing steel in slabs during placement of concrete to check for proper location within the slab. The subgrade below the slab should be moisture conditioned and properly compacted prior to placement of concrete . The structural engineer should design all footings and concrete slabs in accordance with the anticipated loads and the soil parameters given. Retaining Walls Where retaining walls or subsurface structural walls are planned, they should be designed in accordance with the City of Carlsbad Specifications, San Diego Regional Standard Drawing No. C- 7 and the following criteria: Reinforced Fill Retained Soil Foundation Soil Cohesion & Phi Values Cohesion 170 170 170 Friction Angle (Phi) 29 29 29 Backfill 125 pcf 125 pcf 125 pcf The above cohesion and phi values are for the onsite materials, which are anticipated to be utilized as backfill materials. Backfill materials should be inspected by the South Shore Testing and Environmental prior to their use as backfill. Import materials or select backfill materials would require additional testing and recommendations. South Shore Testing & Environmental. W.O. No. 1931503.00U ----.. ---• -• -• -.. .. .. - .. -.... .. ---------.. -.. -.. 1284 Pine Partners, LLC May 27, 2015 Page 7 Backfill Soil Type On-Site Soils Select Granular Equivalent Fluid Pressure Unrestrained Walls Restrained Walls Level 2:1 Sloping Level Backfill Backfill Backfill 38 pcf 36 pcf 45 pcf 43 pcf 40pcf 36 pcf 2:1 Sloping Backfill 50pcf 48 pcf Walls subject to surcharge loads should be designed for an additional uniform lateral pressure equal to one-half the anticipated surcharge pressure in the case of restrained walls, or one-third for unrestrained walls. The wall backfill should be well drained to relieve possible hydrostatic pressures on the wall . Perforated pipe and gravel backdrains should be installed behind all retaining walls to prevent entrapment of water in the backfill. Perforated pipe should consist of 4-inch diameter PVC Schedule 40 or equivalent with the perforations facing down. The pipe should be encased in a 1- foot wide column of ¾ to 1-1/2-inch, open graded gravel extending above the wall footing to a minimum height of 1-1/2 feet above the footing or to a height equal to one-third the wall height, whichever is greater. The gravel should be completely wrapped in filter fabric consisting of Mirafi 140N or equivalent. Solid outlet pipes should be connected to the backdrains and routed to a suitable area for discharge of accumulated water. Weep holes, if used, should be 3-inch minimum diameter and be provided at maximum intervals of 6-ft along the walls. Open, vertical masonry joints should be provided at 32-inch minimum intervals. One cubic foot of gravel should be placed behind the weep holes or open masonry joints. The gravel should be wrapped in filter fabric to prevent infiltration of fines and subsequent clogging of the gravel. Filter fabric should consist of Mirafi 140N or equivalent. Observation of Foundation Excavations In accordance with the 2013 CBC and prior to the placement of forms, concrete, or steel, all foundation excavations should be observed by the geologist, engineer, or his representative to verify that they have been excavated into competent bearing materials. The excavations should be per the approved plans, moistened, cleaned of all loose materials, trimmed neat, level, and square. Any moisture softened earth materials should be removed prior to steel or concrete placement. South Shore Testing & Environmental. W.O. No. 1931503.00U ----.. .. ---• -• ----.. .. .. .. .. .. .. .. -.. --------- ... - 1284 Pine Partners, LLC May 27, 2015 Page 8 Earth materials from foundation excavations should not be placed in slab on grade areas unless the materials are tested for expansion potential and compacted to a minimum of 90 percent of the maximum dry density . Utility Trench Backfill: Utility trench backfill should be compacted to a minimum of 90 percent of the maximum dry density determined in laboratory testing by the ASTM D 1557 test method. It is our opinion that utility trench backfill consisting of on-site or approved sandy soils can best be placed by mechanical compaction to a minimum of 90 percent of the maximum dry density. The upper 1-ft of the utility trenches within streets and driveways should be compacted to a minimum of 95% of the maximum dry density. All trench excavations should be conducted in accordance with Cal-OSHA standards as a minimum . The onsite soils are generally classified as Type "C" soil in accordance with the CAL/OSHA (California, State of 2007) excavation standards. Unless specifically evaluated by the project engineering geologist, all temporary excavations should be performed in accordance with CAUOSHA (California, State of, 2007) excavation standards for Type "C" soil. Based upon a soil classification of Type "C", the temporary excavations should not be inclined steeper than 1.5: 1 (horizontal:vertical) for a maximum depth of 20-ft. For temporary excavations deeper than 20-ft or for conditions that differ from those described for Type "C" in the CAL/OSHA excavation standards, the project geotechnical engineer should be contacted . Surface Drainage: Proper surface drainage is critical to the future performance of the project. Infiltration of irrigation excess and storm runoff into the supporting soils can adversely affect the performance of the planned improvements. Saturation of a soil can cause it to lose internal shear strength and increase its compressibility,. resulting in a change in the original designed engineering properties. Proper drainage should be maintained at all times. All site drainage should be collected and transferred to the street in non-erosive drainage devices. Drainage should not be allowed to pond anywhere on the site, and especially not against any foundation or retaining wall. Landscape irrigation situated within 5-ft of the building perimeter should be enclosed in protected planters and drained away from structures. Positive site drainage should be provided away from structures, pavement, and the tips of slopes to swales or other controlled drainage structures. Any building pad and pavement areas should be fine graded such that water is not allowed to pond. South Shore Testing & Environmental. W.O. No. 1931503.00U -----.. .. .. .. ... ... - ... ... ... .. .. .. .. ... -.. .. .. --------• -- 1284 Pine Partners, LLC May 27, 2015 Page9 Foundation Plan Review Once foundation plans are finalized, a Foundation Plan Review should be performed to review plans and confirm that the plans are in general conformance with recommendations presented in this report . Construction Monitoring Observation and testing by South Shore Testing & Environmental is necessary to verify compliance with recommendations contained in this report and to confirm that the geotechnical conditions encountered are consistent with those encountered . South Shore Testing & Environmental should conduct construction monitoring during any fill placement, footing excavation and subgrade preparation prior to placement of fill or construction materials . LIMITATIONS Our investigation was performed using the degree of care and skill ordinarily exercised, under similar circumstances, by reputable Geotechnical Engineers and Geologists practicing in this or similar localities. No other warranty, expressed or implied, is made as to the conclusions and professional advice included in this report. The report is issued with the understanding that it is used only by the owner and it is the sole responsibility of the owner or their representative to ensure that the information and recommendations contained herein are brought to the attention of the architect, engineer, and appropriate jurisdictional agency for the project and incorporated into the plans; and the necessary steps are taken to see that the contractor and subcontractors carry out such recommendations contained herein during construction and in the field. The samples taken and used for testing and the observations made are believed representative; however, soil and geologic conditions can vary significantly between test locations. The evaluation or identification of the potential presence of hazardous or corrosive materials was not part of the scope of services provided by South Shore Testing & Environmental, or its assigns. The findings of this report are valid as of the present date. However, changes in the condition of a property can occur with the passage of time, whether due to natural processes or the works of man on this or adjacent properties. In addition, changes in applicable or appropriate standards may occur, whether they result from legislation or the broadening of knowledge. Accordingly, the findings of this report may be invalidated wholly or partially by changes outside our control. Therefore, this report is subject to review and revision as changed conditions are identified. South Shore Testing & Environmental. W.0. No. 1931503.00U ----.. ----------.. -- ... ... .... .. .. ... ... .. - --.. -.. --... 1284 Pine Partners, LLC May 27, 2015 Page 10 The firm that performed the geotechnical investigation for this project should be retained to provide testing observation services during construction to maintain continuity of geotechnical interpretation and to check that the recommendations presented herein are implemented during site grading, excavation of foundations and construction of improvements. If another geotechnical firm is selected to perform the testing and observation services during construction operations, that firm should prepare a letter indicating their intent to assume the responsibilities of project geotechnical engineer of record. Selection of another firm to perform any of the recommended activities or failure to retain the undersigned to perform the recommended activities wholly absolves South Shore Testing & Environmental, the undersigned, and its assigns from any and all liability arising directly or indirectly from any aspects of this project. This opportunity to be of service is sincerely appreciated. If you have any questions, please call. Respectfully Submitted, South Shore Testing & Environmental JohnP. Frey Project Geologist ATTACHMENTS Figure 1 -Site Location Map (2,000-scale) APPENDIX A -References William C. Hobbs, RCE 42265 Civil Engineer, Expires 3-31-16 APPENDIX B -Standard Earthwork & Grading Specifications South Shore Testing & Environmental. W.0. No. 1931503.00U ----------... ... ... 111111 ... ... -.. ---... -... -------------- APPENDIX A References South Shore Testing & Environmental W.O. NO. 1931503.00U ----.. .. .. ---... .. ... .. ... ... ... .. -1111 .. ... ... --------• ---- REFERENCES Bresnahan, Kevin, P.E., Undated, "Precise Grading Plan -829 South Pacific Street Condominiums", Sheets 1 & 2 of 2, Scale: 1" = 8'. California Building Standards Commission (CBSC), 2013, "2013 California Building Code, California Code of Regulations, Title 24, Part 2, Volume 2 of 2". California Division of Mines & Geology, 1997, "Guidelines for Evaluating and Mitigating Seismic Hazards in California", Special Publication 117 . California Division of Mines & Geology, 1996, "Probabilistic Seismic Hazard Assessment for the State of California", DMG Open File Report 96-08, USGS Open File Report 96-706 . City of Carlsbad, Revised August 2010, "Retaining Wall B-7" Sheets 1 & 2 of 2 . Coduto, Don, P., 1994, "Foundation Design Principles and Practice", Prentice Hall, pages 637-655 . ESI, 2013, "Preliminary Geotechnical Investigation, Two Residential Lots -TPM MS13-03, 0.26 +/-Acres, Lot 9, PM 1744, APN 205-020-04, 1284 Pine Avenue, Carlsbad, California", Project No . 12-0808-PL, Dated September 5, 2013. Hart, E.W., 2000, "Fault-Rupture Hazard Zones in California", California Division of Mines and Geology Special Publication 42, CD-003 (CD-ROM Version) . Houston, S. L., 1992, "Partial Wetting Collapse Predictions", Proceedings of the 7th International Conference on Expansive Soils, Vol. I, pages 302-306 . Kennedy, M.P., & Tan, Siang S., 2005, "Geologic Map of the Oceanside 30 x 60 Quadrangle, San Diego County, California", California Geological Survey Regional Geologic Map, Scale: 1" = 100,000-ft. Petersen, M., Beeby, D., Bryant, W., Cao, C., Cramer, C., Davis, J., Reichle, M., Saucedo, G., Tan, S., Taylor, G., Toppozada, T., Treiman, J., and Wills, C., 1999, Seismic Shaking Hazard Maps of California", California Division of Mines and Geology Map Sheet 48, varied scales. Proceedings of the 7th International Conference on Expansive Soils, Volume I, "Foundations on Hydro-collapsible Soils, Pages 256-261. San Diego Regional Standard Drawing, August 2009, "Drawing Number C-7". State of California Water Quality Control Board Website, 2015, "Groundwater Information and Geotracker Site Information. Weber, Harold F., Jr., 1963, "Geology & Mineral Resources of San Diego County, California". California Division of Mines and Geology County Report 3, Scale" 1" = 10,560-ft. South Shore Testing & Environmental. W.O. No. 1931503.00U ---.. ... -.. 11111 --... ... ... ... ... .. ---... ... .. -------------- APPENDIXB Standard Earthwork & Grading Specifications South Shore Testing & Environmental. W.O. No. 1931503.00U ---.. .. .. ---... .. ... -... ... .. .. .. .. -.. -.. -------------.. STANDARD GRADING AND li~ARTHWORK SPECIFICATIONS These specifications present South Shore Testing & Environmental, standard recommendations for grading and eanhwork . No deviation from these specifications should be permitted unless specifically superseded in the geoteclrnical report of the project or by written communication signed by Lhe Soils Consulrnnl. Evaluations performed by the Soils Consultant during the course of grading may result in subsequent recommendations which could supersede these specifications or the recommendations of the geotechnical report. 1.0 GENERAL 2.0 3.0 I.I 1.2 I 3 1.4 1.5 1.6 1.7 The Soils Consultant is the Owner's or Developer's representative on the project. For the purpose of these specifications, observations by the Soils Consultant include observations by the Soils Engineer, Soils Engineer, Engineering Geologist, and others employed by and responsible to the Soils Consultant. All clearing, site preparation, or eai1hwork perfonncd on the project shall be conducted and directed by the Conlractor under the allowance o.- supervision of the Soils Consultant The Contractor should be responsible for the safety of the project and satisfactory completion of all grading. During grading, the Contractor shall remain accessible. Prior lo the commencement of grading, the Soils Consultant shall be employed for the purpose of providing field, laborntory, and office services for conformance with the recommendations of the geotechnical report and these specifications. It will be necessary that the Soils Consultant provide adequate testing and observations so that he may provide an opinion a~ to determine that the work was accomplished as specified. lt shall be the responsibility of the Contractor to assist the Soils Consultant and keep him apprised of work schedules and changes so that he may schedule his personnel accordingly. It shall be the sole responsibility of the Contractor to provide adequate equipment ,md methods to accomplish the work in accordance with applicable grading codes, agency ordinances, these specifications, and the approved grading plans It'. in the opinion of the Soils Consultant, unsatisfactory conditions, such as questionable soil, poor moisture condition, inadequate compaction, adverse weather, etc., are resulting in a quality of work less than required in these specifications, the Soils Consultant will be empowered to reject the work and recommend that construction be stopped until the conditions are rectified . It is the Contractor's responsibility to provide safe access to the Soils Consultant for testing and/or grading observation purposes. This may require the excavation oftest pits and/or the relocation of grading equipment. A final report shall be issued by the Soils Consullanl attesting to the Contractor's conformance with these specifications. SITE PREPARATION 21 2.2 2.3 2.4 2.5 All wgetation and deleterious material slrnll he disposed or on~sile. This removal sh,111 be obs,:rvcd by the Soils Consultant and concluded prior to ti II placement. Soil, alluvium, or bedrock maierials determined by the Soils Consultant as being unsuitabk for placcmc111 in compacted fills shall be removed from the site or used in open area; as determined by the Soils Consultant. Any material incorporated as a pa11 ofa compacted fill must be approved by the Soils Consultant prior to fill placement. After the ground surface to receive !ill has been cleared, it shall be scarified, disced and/or bladed by the Contractor until it is uniform and free from ruts, hollows, hummocks, or other uneven features which may prevent uniform compaction. The scarilicd ground surface shall then be brought to optimum moisture, mixed as required, and compacted as specified. If the scarified zone is greater than twelve inches in depth, the excess shall be removed and placed in lifts not to exceed six inches or less. Prior to placing lill, the ground surface to receive fill shall be observed, tested, and approved by the Soils Consultant. Any underground structures or cavities such as cesspools, cisterns, mining shafts, tunnels, septic tanks, wells, pipe lines, or others are to be removed or treated in a manner prescribed by the Soils Consultant. In cut-fill transition lots and where cut lots arc partially in soil, colluvium or unweathered bedrock materials, in order to provide unifom1 bearing conditions, the tedrock portion of the lot extending a minimum of 5 feet outside of building lines shall be overexcavated a minimum of 3 feet and replaced with compacted fill. Greater overexcavation could be required as determined by Soils Consultant. Typical details are attached. COMPACTED FILLS 3.1 Material to be placed as fill shall be free of organic matter and other deleterious substances, and shall be approved by the Soils Consultant Soils of poor gradation, (:xpansion, or strength characteristics shall be placed in areas designated by Soils Consultant or shall be mixed with other soils to serve as satisfactory fill material, as directed by the Soils Consultant. ---.. ------.. ... -.. ... --.. -- ----------- Standard Grading and Earthwork Specifications Page 2 4.0 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 3.10 3 11 3 12 3.13 3.14 CUT SLOPES 41 4.2 4.3 4.4 4.5 Rock fragments less than si~ inches in diameter may be utili;:cd in the fill, provided: They arc not placed or nested in concentrated pockets There is a sufficient amount of approved soil to surround the rocks. ·me distribution ofrocks is supervised by the Soils Consultant. Rocks greater than twelve inches in diameter shall be taken off-site, or placed in accordance with the recommendations of the Soils Consultant in areas designated as suitable for rock disposal. (A typical detail for Rock Disposal is attached.) Material that is spongy, subject to decay, or otherwise considered unsuitable shall not be used in the compacted fill. Representative samples of materials to be utilized as compacted fill shall be analy,.ed by the laboratory of the Soils Consultant to detcnninc their physical properties. If any material other than that 1,rcviously tested is encountered during grading, the appropriate analysis of this material shall be conducted by the Soils Consultant before being approved as fill material . Material used in the compacting process shall be evenly s1>rcad, watered, processed, and compacted in thin lifts not to exceed six inches in thickness to obtain a unifom1ly dense layer. The fill shall be placed and compacted on a horizontal plane, unless otherwise approved by lhc Soils Consultant If the moisture content or relative compaction varies fi'orn that required by the Soils Consultant, the Contractor shall rework the fill until it is approved by the Soils Consultant. Each layer sh,il! be compacted to at least 90 percent of the maximum density in compliance with the testing method specified by the controlling governmental agency or ASTM I 557-70, whichever applies. If compaction to a lesser percentage is authorized by the controlling governmental agency because of a specific land use or expansive soil condition, the area to receive fill compacted to less than 90 percent shall either be delineated on the grading plan and/or appropriate reference made to the area in the geotecfmical report. All fills shall be keyed and bencl1ed through all topsoil, colluvium, alluvium, or creep material, into sound bedrock or finn material where the slope receiving fill exceeds a ratio of five horizontal to one vertical or in accordance with the recommendations of the Soils Consultant. The key for side hill fills shall be a minimum width of 15 feel within bedrock 01 firm materi;1ls, unless otherwise specified in 1hc gcotechnical report (See detai I attached ) Subdrainagc devices shall be co11stn1ctcd in compliance with the ordinances of the controlling governmental agency, or with lhc rccomm~ndation;; of the Soils Consultant. (Typical Canyon Subdrain details arc attached.) The contractor will be required to obtain a minimum relative compaction of at least 90 percent Olli to the finish slope face of 1111 slopes. buttresses, and stabilization tills. This ma)' be achieved by either over building the slope and cutting back to the compacted core, or by direct compaction of the slope face with suitable equipment, or by any other procedure, which produces the required compaction approved by the Soil:; Consultant. All 1111 slopes should be planted or protected from erosion by other methods specified in the Soils report. Fill-over-cut slopes shal I be properly keyed through topsoil, colluviwn or creep material into rock or firm materials, and the transition shall be stripped of all soil prior to placing fill. (See attached detail.) The Soils Consultant shall inspect all cut slopes at vertical intervals exceeding five feet. If any conditions no1 anticipated in lhe geotechnical report such as perched water, seepage, lenticular or confined strata of a potentially adverse nature, unfavorably inclined bedding,joints or faLrlt planes encountered during grading, these conditions shall be analyzed by the Soils Consultant, and recommendations shall be made to mitigate these problems. (Typical details for stabilizalion ofa portion ofa cut slope are attached.) Cut slopes tJ;at face in the same direction as the prevailing drainage shall be protected from slope \\~dsh by a non-erodible interceptor swale placed at the top of the, slope Unless otherwise specified in the geotechnical report, no cut slopes shall be excavated l1igher or steeper than that allowed by th~ ordinances of controlling governmental agencies. Drainage ten aces shall be constructed in compliance with the ordinances of controlling governmental agencies, or with the recommendations of the Soils Consult.ant. ----------· -----.. ----... ... - ... ... -... ---.. ... -... -... ----------- Standard Grading and Earthwork Specifications Page 3 5.0 6.0 7.0 TRENCH BACKFILL~ 5.1 5.2 5.3 5.4 5.5 5.6 Trench excavation shall be inspected prior to structure placement for competent bottom. Trench e~cavations for utility pipes shall be backfilled under the supervision of the Soils Consultant. After the utility pipe has been laid, the space under and around the pipe shall be backfilled with clean sand or approved granular soil to a depth of at least one fool over the top of the pipe. The sand backfill shall be unifonnly jetted into place before the controlled backfill is placed over the sand. The on-site materials, or other soils approved by the Soils Consultant, shall be watered and mixed, as necessary, prior to placement in lifts over the sand backfill. The controlled backfill shall be compacted to al least 90 percent of the maximum laboratory density, as determined by the ASTM DI 557-70 or the controlling governmental agency. Field density tests and inspection of the backfill procedures shall be made by the Soils Consultant during backfilling lo see that proper moisture content and uniform compaction is being maintained. The contractor shall provide test holes and exploralmy pits as required by the Soils Consult,mt to enable sampling and testing . GRADING CONTROL 6.1 6.2 6.3 6.4 Inspection of the fill placement shall be provided by the Soils Consultant during the progress of grading. In general, density tests should be made at intervals 1101 exceeding lwo feel of fill height or every 500 cubic yards of fill placed. This criteria will vary depending on soil conditions and the size of the job. In any event, an adequate number of field density tests shall be made to verify that the required compaction is being achieved. Density tests should also be made on the native surface material to receive fill, as required by the Soils Consultant. All clean-out, processed ground to received fill, key excavations, subdrains, and rock disposals should be inspected and approved by the Soils Consultant prior to placing any fill. It shall be the Contractor's responsibility to notify the Soils Consultant when such areas will be ready for inspection. CONSTRUCTION CONSIDERATIONS 7.1 7.2 7.3 Erosion control measures, when necessary, shall be provided by th<' Contractor during grading and prior to the completion and constniction of p~rmancnt drainage controls. Upon completion or grading and icnnination of inspections by the Soils Consult.int, no further filling or excavating, including that necessary !'or footings l<.mrH!ations, large tree wells, retaining walls, or other fcallltes shall be performed without the approval oflhe Soils Consultant. Care shall be taken lly the Contractor during final grading to preserve any berms, drainage terraces, interceptor swalcs, or other devices of permanent nature 011 or adjacent to the property ROCK DETAIL FINISH GRADE ____________ ,_,:::-_--------------------TO' MIN _____ COMPACTED:::::---: SLOPE FACE GRANULAR SOlL To fiTT voids1 densified by flooding PROFILE ALONG WINDROW TRANSITION LOT DETAILS CUT-FILL LOT ----------NATURAL GROUI 1--. ---------. 5' L_ -_.,.,,. MIN. f~- ..---- CUT LOT UNWEATHERED BEDROCK OR __ j ,-MATERIAL APPROVED BY f THE GEOTECHNlCAL CONSUL TANT NOTE: Deeper overexcovation and recomoaction shall be performed if de, ermined ·o be necesscry by the geotechnicc I consultant. OUTLET PIPES 4'1 fJ ~nperforated Pipe, 1001 Mox. O.C. Horizontolly 301 Mox. O,C. Vert leaf ly ' --------- KEY 1•: ________ _ DEPTH ----_-_-_--::.2%:...-_ _1 ---~<1 -------------~ --_-:_-____ -__ 2;~M-.--======------·---10· In .. --_____ -..,;:. ----T ------,,.-------/- z, MfN. ~----KEY WIDTH--.--I c::ourP.,'.3-IT SIZ=: -GENEnALL y 15 FEE.T 7 TE.',1PORARY FlLL LEVE."l. ~;_ _ ; flECOMPACTED Fll.L -:.-=:..·. 6"{'1IN. SE!..ECT BEDOING -BACK Fill.. ·" P Ml,"l. NONPf:r/;"ORATED '------...... _/,,.,,,, "--•.,..._..,._ ...__.._,_...,_ •-.._.,.,.,<''"""'-~v~,;••"''' DETAJL A-A" _____ , _________ ,.,.......,.,..., .... ...,,.~,,~ NOTES: ........ --·-.,,........,. ... <;j,• Fill blanket, back cu·r, key width ond key depth are subje::ct to field change~ per report/plans. -----------------------------------------------------FIL TcR MA 7ERlAl. 3 (1_ 3111. T-CONNECT!ON PERFORATED PIPE 4n i!l MIN. ALTERNATE A ALTERNATE B -~----------,,,....--------,, FILTER MA TERU\L_: Filter material shall be Closs 2 permeable material per State of Califor:7io Standard Specifications, or approved alternate. Class 2 grading as follows: 4" Mlt e Key heel svbdro in, blanket droin~ or vertical drain may be required at the discretion of the gf::otechnicol consi..i!tont. II,? SU8DRAlN INSTALLATION -Subdroin pipe shol I be installed with perforations down or, at locations designated by SIEVE SIZE PERCENT PASSINC the geotechnic9l consultant, shall be nonperforoted pipe. ~ s_y~1;:u_={~ir-J:Y.f. E, -Suqd~o in type shall Q~, ~~TB .. -,~t.S.PR 23.5 or ASTM "01527, ,sctte~ · 40; l!-\"ti:'"1""nitrik9 1:1. ~·-,4• ---~-~.,,. .. -w~;,,,.,.~-·,,.,,. , &.>\,I~,~~ Styrene tcA.§,9JJ.J~~,r~J?-)a9.~.,,.4. s~8. 2~~..!>~ -~s™ . ·p178.?.t .. §.~~~-40 _P~ly~yJ. Ctoor,de Plastic (PV~l)JJE~r ~~. ~f-~'<?Y.ed-, ~ql!iva~nt. . . ,_,, . - ...... ,-•--.-r;-:--· .. I II , 3 /4 II 3/8" No.4 No. 8 No. 30 No. 50 No. 200 100 90-100 40-100 25-40 18-33 5-15 0-7 0-3 ---------------__,, FILL SLOPE ----------------------. NOTES: To be constructed prior to fi !I placement LOWEST BENCH: Depth and width subject to field change based ori cons\..lltant's inspection. S~1BDRA!~,JAGE: B-:-,c-k d:-_::.;~~$ mcy be required ot the ::ii:scret ion of the geotechnico{ consultant. SUBDRAlN Perforated Pipe Surrounded With AL TERNA TE A: Filter Material ~FILTER ~ATER JAL / 9 ft. /ft. r.: COVER--~ ;::;--"'_ BEDDING =-~✓t-::-r~-,';'1-.,..,..,-~,,-, A!temat L}" M!N.7" ,__, ·A;·ern.ate ~ PERFORATED PIPE SUBDRAIN TRENCH SEE Al TERNA TES A& B A-2 FILTER MATERlAL: Filter moleriol shall be Clos:; 2 perrne<:1ble ma7eriol per Slok of Co1ifornio SJondord Spedficotions, or op proved ol ternote. Closs 2 grading os fo!low.s: I" 3/lJ" 3/8" No. 4 No. 8 No. 30 No. 50 No. 200 f'J::RCENT PAS'. 100 90--100 40-100 25-40 18-33 5-15 0-7 0-3 611 f) MIN. _.>-~----------------.-·------·-·-··--------·-·-----------·-----------··--~---·-·---·--~---~~ -··---------. ---~------~ uaonAJN TERNATE B: --··---,-----·----------·-- 1 'i/2" Gravel Wrapped ir:i Ffrl. er F 2 bric ~ / MIR.A.Fl 140 Fil TER __ FABRIC OR APPROVED EQUIVALENT I 3/211 MIN. GRAVEL OR APPROVED EQUIVALENT 9 ft. 3/ft. NOTE: In oddirion -/o iht: 'N,o 9rovel, outlet portion of subdrain 5hould be equi: with a minirnum of 10 long perforated pipe nect ed to o nonperforoied having a minimum of 5 f N I ength inside the ,,vra~ grov-e!. SUBORAIN INSTALLATION -Subdroin pipe shall be installed with perforations ~wn or, at lccation.s designated by the geotechnicol cons.u!tant ~ shall be nonperforated prpe. SUSOR~fN TYPE -Subdfagn type shall be ASTM 0275"ti SOR 23.6 or ASTM 01527, Schedule 40 AcryJonUrlle 'But8dlene Styrene (ABS) or ASTM 03034 SOB 23.5 or ASTM 01785, Schedue 40 Polyviwl Chloride Plastic (PVC) pipe or approved ·equiva!ant. . ~ '. •· . APPENDIX F PRELIMINARY GEOTECHNICAL INVESTIGATION (UPDATE) SEPTEMBER 5, 2013 W. C. HOBBS, CONSULTING ENGINEER PRELIMINARY GEOTECHNICAL INVESTIGATION TWO FESIDENT AL LOTS -TPM MS13-03 0.26 +/-Acres, Lot 9, PM 1744, APN 205-020-04 1284 Pine Avenue, Carlsbad California PROJECT NO. 12-0808-PL SEPT. 5, 2013 UPDATE ONITlAL REPORT PREPAFED AUGUST 20, .2012) PREPARED FOR: David Fischbach c/o Kevin P. Bresnahan 3031 Ridge Creek Drive Fallbrook, California 92028-2690 ------ 4 I 659 Date Street. Ste. #202 • Murrieta. CA 92562 • M (951) 461-3 I 11 .., (951) 461 -"'133 (Initial Report Prepared August 20, 2012) ?ro7ect No. 12-0808-PL Sept. 5. 2013 Update 1.0 INTRODUCTION At your request, we have performed a Preliminary Geotechnical Investigation for the two proposed 1 & 2 story single family residences with attached garages and access driveways at the above referenced site as indicated on the Proposed Tentative Parcel Mep MS13--03. The purpose of our investigation was to evaluate the underlying soil conditions with respect to the proposed development and to assess the geotechnical and engineering constraints that might eltlst considering this development. The IO-Scale Site/Retaining Wall Plan prepared by Bresnahan Engineering, Fallbrook, dated August 2012 was the basis of our field measurements, and was used to direct our field work. Plate 1 presents our Geotechnical data obtained during our field investigation. At the time of our investigation the property comers had been surveyed and staked, and the east½ of the site is occupied by an existing residence with fencing on four sides. Since our initial field investigation, a tentative parcel map (I'PM MS 13-03) llilS been prepared and submitted to the city of Carlsbad. Additionally, the northerly halfof the property (Proposed Lot 2 of the TPM) has been developed with a primary residence and attached secondary :residence. The northerly ½ of site has been grading and retaining walls installed per the Minor Grading Plan PC 12-53. Last, the demolition and minor earthwork of the existing residence on the southerly ½ of the property ( approximately the Proposed L-Ot 1 of TPM MS l 3•03) has been completed. rt is the purpose of this update report prepared to address the aforementioned changes since our initial field work. Precise Grading Obsen-ation and Field Density Testing for Lot 2 of MS 13-03 was documented by us and submitted to the city iu our report dated October 26, 2012 as ESI project No. 12-1002-GR. We have reviewed our initial Preliminary Soils Report Dated August 20 2012 and deem the recommendations compatible with the proposed development of the southerly½ of site (Lot 1). Since the 10-Scafo Site/Retaining Wall Phm prepared by Bresnahan Engineering, Fallbrook, dated August 2012 indicated the intentions of splitting off and devoloping the southerly ½ of the parcel, said lot was considered in preparation of the initial preliminary soils report Although the demolitioa. and over-excavation oflot 1 was observed by us, a field review and verification of field density testing will need to be performed prior to the site development of the southerly half and submittal of an Observation and Field Den.sity Testing Report will be needed. ACCOMPANYING M'AFS, ILLUSTRA.TIONS AND APPENDICES I n de x L·'L3 [) -( 2 0 0 0 -s ca 1-e ) -Page ? ?late l (In Pocket) ~ppcnciix C -~e~erai Ear~hwark and Grading Specificacions TPM MS13-03 DATED sept. 5, 2013 Update (In Pocket) r n s 12 S . 0 2000 SCALE SOURCE: 4000 ~ feet INDEX MAP .. >···· ----~ -~.i n'l:--,.:~::~-i, -\ ·-~ --~-.... 1\ .· ::f -~>. ----) •N '\ ""' ·Y··,• 1, ,_ . .'\)/.;~-.)( ·" r-•,.•-·-. .,. / "_/r ··~--~.'• ~\ C\ \ ,:; }'\ ~ ;\J'1A ·} /\ "l:{>i · 1 \ •i,: '. :··,, I 'i L __ I .. ti_.,, /, )J / ,{ {(~-) j/;~IJ[I:'. : '·, ,:. /, ___:~~.\ (,. / I ',\ ,:-fl. r,;f . . _..,•· . ., --...... /. ,:.r7.-:> ,:,..•· INDEX MAP OF 0.26+/-ACRES, LOT 9, PM 1744, APN 205·020-04 1284 PINE AVENUE CARLSBAD , CALIFORNIA -2- U.S GS. 7 ½ MIN. QUAD. SAN l. lJ IS RFY 1 qf;p, rPR 1 CJ7S) N --- -.. ------.. -.. ---------------------- 12-O808-PL Sept. 5, 2013 Update Page 3 2.0 SITE LOCATION/CONDITIONS The rectangular sh.aped 0.438+/-acre property is located on the west side of Pine Avenue, an improved paved road in the City of Carlsbad, San Diego County. Pine Avenue bounds the property on the east, with existing houses in all remaining directions. The Index Map (page 2) presents topogmpghic and geographic relationships of the property to surronding areas. Topographically, the existing property in the area of the proposed development has an elevation of 105.0 to 111.3 feet. The proposed finished pad on the northerly 1/2 portion is at an elevation of 107 .4 feet. The proposed. The south 1/2 of the lot has a 2-3 foot high 2: 1 fill slope. The lot is draining to the south to Pine Avenue via sheet :flow and yard dnrlns with gradients of 1-4 % and 0.5-2%, respectively. 3.0 PROPOSED DEVELOPMENT According to the referenced 10 scale Tentative Parcel Map MS 13-03 the 0.438+/-acre lot wilt be subdivided to create a "flag lot" on the northerly 0.26 +/-acre. Gravity walls to a maximum height of 4.5 feet are proposed on the north, east and west side of the proposed lot. Minor grading for the proposed subdivided lot will consist of cut and fill to a maximum of 3 feet at finished face inclinations of 2: 1 (horizontal to vertical) or flatter for the pad and driveway access. Drainage will be to the south via sheet flow and yard d.nriru! with gradients of 1-4 % and 0.5-2%, respectively. The existing structure and detached garage on the on the south have been demolished. Minor grading was performed as part of the demolition of the footings and retaining walls, with the existing grades modified to acoomodete drairulge after the demolition. A precise grading plan will be required upon development of the southerly 1/2. 4.0 SCOPE OF SERVICES The scope of ou~ investigation included the following: 4. A review of available data pertinent to the site. Subsurface exploration of the site utilizing 1 exploratory hnr~,, r ,-'ap-t-h5 as g,,."'ar :1.::: .<-/ ::; Feot ~l'n-, ' ri ,, ::i, ~-n. .• • ....... ~, .. g .... J '-L ........... 1.... .t ......... ~ u.__J ... .; • ~J ..1.. \.:.. • : • E-DO,. : .... ~g ,/oS logged, and tnis log appears in Appenaix A of tn1s report. The boring was tested for in-place density utilizing the California Split-Ring Drive ASTM □2216). Representative bulk samples ~ere obtained for testing. ~aboratory testing of representative earth materials to develop soil engineering parameters for the proposed developm,?nt. Preparation of this report presenting our findings, conclusions ar1d recorn:1'.endations concerning site developrrient. baseri up~n ar engineering Analysis of the geotechnical properties of the subsoil as determined by field and laoo~at □=y evaluation. ----------.. .. -.. -.. --- ------------------------ 12-808-PL {Sept. 5, 20t3 Update) Page 4 5.0 LABORATORY TESTING The tallowing tests were performed for this project in our laboratory in accordance with the American Society for Testing a~d Materials, the State of California Standard Specifications or contemporary practices of the soil engineering profession. 5.1 Maximum Density -Ootimum Moisture Determinations This test determines the density that a soil can be compacted to at various ccntents. For each soil, there is a maximum dry density obtained and the associated optimum moisture content. The results are used to evaluate the natural compaction, control of the grading process and as an aid in developing the soil bearing capacity. This is based on ASTM Standard D1557-00 (five layer method) . These tests consisted of weighing and measuring drive ring samples from the boring in accordance with ASTM 2216. The results are used to analyze the consistency of the subsoil and aid in determining the necessary grading to prepare the pad area. 5.3 Sieve Analysis This test (ASTM D422) determines the material grading of the individual particle sizes and is used in generating an engineering classification. 5.4 Sand Eauivalen~_Te~tjng Thi.sis a test (ASTt·1 D2~!19) fot-t.ne ~~api.d der.ermi.nat.i.on of the relative portions of fine silt and clay materials within the soil samples, and is used for a relative comparison of soils in the determination of the adequate paving sections for driveways, etc. 5.5 Expansion Testinq The expansion index of the soils is determined by the ASTM 04829 and is used to design foundations for anticipated expansion forces. A direct shear s:rength test (ASTM □3080) was performed on a representative sample of che on-site soils remolded to 90% relative compaction. To simulate possible adverse field conditions, the sample was saturated prior to shearing. A satL:r~~ing device was used whic~ permitted the samples to absorb moisture while preve~ting volume change. This test is used to -----.. -----.. ... ... -.. -.. ---· --... --------------- 12-0808-PL {Sept, 5, 2013 Update) Page 5 foundation bearing capacity. 5.7 Soluble Sulfate A representative surface sample was tested (CTM 417) to determine soluble sulfate content. The test results are used to recommend the type and strength of concrete to be used in construction. 5.8 Soil Resistiv-i_ty ___ &_E_H A representative sample was obtained and tested utilizing the CTM 643 test method. The results are use to determine corrosion potential for underground metal utilities and facilities . 5.9 Chloride Content The chloride content of representative finished grade soils was tested utilizing the CTM 422 method. The results are used to determine potential corrosion of subsurface soils. 5.10 Consolidation An in-situ sample was tested for consolidation and collapse utilizing ASTM 02535 procedures. The sample is incrementally loaded to determine compressibility. The sample is inundated with water through a porous stone during testing to determine collapse potential. 6.0 SUBSURFACE CONDITIONS The area of the residential addition is covered by a 2-4 foot thick soil/colluvium. In-place density for the soil/colluvium is 103.6 }')Cf (87.3·% .reLati·ve corn.pact.Lon) .-:~t. 5.8% mo.isture, in B-1 at 1.3-1.E{ feet, to a rnaxi.m:~1!n of 113.81 pc.f (9S.9~i relat.i,.re co::rpa·:-;ti.on) ~l:. 6.6~~ rnoisture in 3-1 at. 3.2-3.6 fE!et. The underlying Quaternary Older Marine Terrace was dense co very clense wi.t.h in-place density of 117 .1 pcf (95. 7% relative compaction) to 1.18.3pcf (96.7% rcl.ative compaction) at moistures of 7 percent ac depths of 5 -8 feet in 8-1. 7.0 GROUND WATER No ground water seepage was encountered on the site to a depth of 37.6 feet. Historic high ground water is expected to be 105-110 feec (elevation 0-5 feet) at the location of the proposed addition based o~ Miller, Morton, Edington, (1975). No evidence of seepage was seen in the natural or constructed slope faces descending from the property to Pine Ave or on the west side of the lot. -------·-·· --- ... .. .. .. .. ---------- --------... - 12-0808-PL (Sept. 5, 2013 Update) Page 6 8.0 FLOODING According to the Federal Emergency Management Agency and the County of San Diego, the pad site is not located within the boundaries of a 100-year flood plain. No swales or drainages cross the site and no flooding hazard exists for the pad area or access driveway from Pine Avenue. Runoff is currently directed off-site fro~ the residence to the Pine Avenue via sheet flow and swales . 9.0 GEOLOGY The entire proposed additional building pad area is underlain at depths below 3-4 feet by a Quaternary Marine Terrace Miller, Morton, fife(, 1975). No evidence of slope instability exists at the site or in the existing cut and fills slopes in adjoining areas to the north and west along Pine and Highland Avenues to a maximum height of 8-10 feet at finished face inclinations of 1.5:1 (horizontal to vertical) or flatter . The site is nat included in any State or Cou~ty fault hazard zone for active faulting. 10.0 SEISMIC SETTING/GROUND MOTION PARAMETERS The regional seismic setting is shown on Plate 2. The nearest active faulcs to the site include the Rose Canyon/Newport Inglewood fault 3.6 km west, the Elsinore fault 31.1 km to the northeast, and more distant, the San Jacinto fault which is located approximately 55.8 km to the northeast. The Rose Cany~n/Newpcrt Inglewood fault because of its proximity and seismic potential to the site is the design fault when evaluating the site seismic parameters. 11.0 HISTORIC SEISMICITY During the last 100 years in the San Diego County area, the greatest number of moderate to large earthquakes (greater than 6.0 Ml have 02curred along the northern portions of the Newport- Inglewood fault and Whittier Fault (Hileman, Allen and Nordquist, 197~1; Peterson, .et al.l, 1996). 'T'he rnost si.gnificant ea..rt!1quake epicenter within 28 miles of the site was the magnitude 6.3M on che N~wporc-Inglewood fault in 1933. Several historic earthquakes of magnitude 5.5 to 6.0M have occurred on the Whittier and Norwalk faults historically including the magnitude 5.9 "Whittier Narrowsu earthquake in 1987 approximately 42 miles northeast. Several older earthquakes along the so~thward extension of the Elsinore fa~lt have occurred tc the so11theast 35-50 miles. ------.. - --·· -.. .. .. -.. .. .. .. ---.. ---------------.. 12-0808-PL (Sept. 5, 2013 Update) Page 7 12.0 SEISMIC EXFOSURE Although no precise method has been developed to evaluate the seismic potential of a specific fault, the available information on historic activity may be projected to estimate the future activity of the fault. This is usually done by plotting the historic activity in terms on number of events in a given time interval versus magnitude of the event. Based on such plots, recurrence intervals for earthquakes of given magnitudes may be estimated. A probabilistic evaluation of potential seismicity for the site utilizing FRISKSP (Blake 1998) indicates a 10% probability of exceedance of 0.31g in 50 years assuming all sE:, i smic sources. itie have utili.zed strain rates of 3.5 mm/year for the Rose Canyon fault suggested by Peterson, et al (1996), Lindvall & Rockwell (1995) to estimate the maximum moment earthquake. We estimate the maximum moment rna9ni t ude er "dFa)S i.gn earthquake" for the Rose Canyon fault tc be 6.9 magnitude with a 10% possibility of exceedance in SO years. This is in agreement with the proba:Oilist.ic model by Blake, (1998). 12.1 2007 C.B.C. Seismic Parameters: The site coordinates are N33.449, W-117.642 Per ASCE Standard 7- 05, Figures 22-3 and 22-4, the maximum considered earthquake (MCE) ground motion for the site Class B (5% critical damping) are as follows: Nearest ~n ... ctive Seisrnic Sot1rce (Type B Fat.llt) -· 3.2krri Ss 1~433 :.. a:1 ---1 . 0 SM 3 1. ,;33 SD_, :..:a 0.956 S: = 0.513 1:,: = 1. 0 SM~ 0.51.3 SD, = C. 342 Per ASCE Standard 7-05, Table 1, the site is classified as Site C:las.s 8. 13.0 GROUND MOTION CHARACTERISTICS The ground motion characteristics which could affect the site du~ing the postulated maximum moment magnitude of 6.9 on the Rose Canyon fault were estimated. Available information in the literature about maximum peak bedroc~ acceleration and its attenuation with distance (Joyner and Borzognia, 1994), the effects of site-soil conditions on surface ground motion pararneters (Seed £< IdrEiss, J.982), an.d site response criteria [Ha_ys, 1980) \•/ere utilizeci. ------------------------···· ------------.. .. .. .. -.. ----------- -.. - - 12-0808-PL (Sept. 5, 2013 Update) Page 8 The predominant period of bedrock acceleration is expected to be 0.30 seconds with 20 seconds of moderate ground shaking (Bolt, 197 3) . 14.0 SECONDARY SEISMIC HAZARDS The very dense nature of the underlying Quaternary Older Marine Terrace in the area of the proposed addition at depths as shallow as 2-4 feet, and the historic depth to ground water over 105 feet in the area of the proposed addition precludes such secondary seismic hazards as liquefaction, lateial spreading or settle~ent of the ground the addition is being placed upon. The potential for seismically-triggered landslides is discussed in detail under the slope stability section . 15.0 CONCLUSIONS AND RECOMMENDATIONS 15.1 Foundation Design A strip and spread footing foundation system should provide an adequate foundation for one and two-story buildings in this site. All exterior footings should be founded a minimum of 18 inches below adjacent finished grade for two-story buildings, and 12 inches for one-story buildings. Interior footings may be founded a minimum of 12 inches below finished grade. When the footings are founded in properly compacted fill or dense soil/colluvium, an allowable bearing capacity of 1500 psf for 12 inch wide footings is acceptable for dead plus live load. This value may be increased by one-third for short term wind and seismic loading conditions. rli~ien foundations are placed in natural soi.ls, no cc>bbles over 6 inches should be left within the base of the foundation. A typical foundation design is included in Appendix C. Two No. 4 f__;ars, l toi:-1 ant-:l l t"Jottcrn is recorrunencleci as a n1in.irnurn design. 15.2 Settlement Our subsurface investigation revealed that the soils beneath the proposed residential addition are loose soil/colluvium over dense older marine terrace to a depth of 3-4 feet. Footings should experience less than 1-inch settlement with less than 1/2 inch differential settlements between adjacent footings of similar sizes and loads when the foundation soils are compacted Lo engineered fill standards. This sectlement is based upon grading of up to JO feet of fill over a distance of 50 feet ho~izontally. Zf thicker fills are p~oposed, settlement could be greater and should be evaluated prior to placement. -.. .. -.. .. ----.. .. .. .. -.. .. ---... .. --------------.. 12-0808-?L (Sept. 5, 2013 Update) Page 9 15.3 Concrete Slabs-On-Grade Sufficient fine-grained materials exists within near surface earth materials to possible create moisture problems. Therefore, we recommend that a moisture barrier be placed under any concrete slabs that might receive a moisture-sensitive floor covering. This moisture barrier should consist of a 10-mil polyethylene vapor barrier sandwiched between a 1-inch layer of sand, top and bottom, to prevent puncture of the barrier and enhance curing of the concrete. Reinforcement of the slabs with No. 3 bars on 24- inch centers mesh centered in the S inch slab is recommended . The sub grade below the slab should be moisture conditioned and properly compacted prior to placement of concrete . 15.4 Expansive Soils -Soluble Sulfate Expansion testing of near-surface silty sand soils (B-1; 0-4 feet) possible at finished grades indicate that the soils in the pad area are very low expansion. No special design provisions ar0 ~ecessary for the foundation or concrete flatwork to resist expansion forces as shown on the Foundation and Slab Recommendations for Expansive Soils in Appendix C. This is in accordance with the U.B.C. Table 18-8-1. The soluble sulfate content was 125 ppm allowing normal Type II concrete with 2500 psi strength . 15.5 Soil Resistivity & pH The representative subsurface soils anticipated at finished grades were obtained and tested utilizing the CTM 643 test method. The results are pH= 7.1 and Minimum Resistivity= 2700 ohm-c~. No special provisions for buried metal utilities or facilities are required. 15.6 Chloride Content The chloride content of representative soils was determined ut:iliz.Lng LhE' CTM 422 tes1: method and yielded a chloride content of 145 ppm. No special mitigation for corrosion of ferrous underground utilities is required. 15.7 Earthwork Shrinkage and Subsidence Shrinkage of the existing soil/colluvium fill will occur during grading, estimated as 4-6 percent when recompacted to compacted f_:_J..l standarcis. ---... -... .. ---.. ... ... ... ... ... .. .. .. .. ... ... .. .. - 111111 ----------- 12-0808-PL {Sept. 5, 2013 Update) Page 10 15.8 Retaining Wall Design Retaining walls should be designed using the following parameters: o Active pressure (level backfill) 49 lb/ft /ft o Active pressure (2:1 backfill) 57 lb/ft /ft o Active pressure (1 1/2: 1 backfill) 92 lb/ft/ft for purpose of lateral resistance, a value of 0.35 may be used for frictional resistance. A value of 275 lb/ft /ft may be used for passive resistance for footings placed into properly compacted fill. Frictional and passive resistance may be combined, provided the later is reduced by one-third . Special loads for dead plus actual loads should be considered in t;e driveway/parking area that is retained . 15.9 Lateral Loads Lateral loads in the near-surface soils are: At: Rest Passi.ve 48pounds per square foot of soil depth (psf/ft) -59 psf/ft -275 psf/ft (for wood shoring) 350 psf/ft (for concrete footings) Active means movement of the structure away from the soil; at rest means the structure does not move relative to the soil (Such as a loading dock); and Passive means the structure moves into the soil. The coefficient of friction between the bottom of the footings and the native soil may be taken as 0.35 . 15.10 Trench Stability The near-surface soil to a depth of 5 feet may not stand vertically when excavated. Trenches in excess of 5 feet in depth should have the sides laid back at 1:1 in accordance with OSHA requirements. 15.11 Slope Stability The proposed and existing grading indicates the maximum cut and fill slope height is 3-4 feet at finished face inclinations of 2:1 or flatter at the rear and west side of the property. No slopes higher than 4 feet are planned in the area of the proposed addition. The high strength values allow 2:1 (horizontal to vertical) fill slopes up to 30 feet without gross or surficial instabil.i.t:ya ---.. -.. -.. --.. .. .. .. .. .. - 111111 -.. -.. .. -------------.. .. 12-0808-PL (Sept. 5, 2013 Update} Page 11 Selection of Shear Strenqth ?arameters The following shear strength parameter utilized for our slope stability analysis was determined by our laboratory test results as presented below: Material (Cut. or F'ill) Anticipated en-Site Fi. 1l. fr.i ct ion Ang le (Decree) 29.0 Cohesion lb/fe 170 We have utilized values of 29.0 degrees and 170 lb/ft2 for older marine terrace natural slopes although it represents a conservative number, determined from a remo.lcied saturated sample. In-situ terrace is expected to be 20% + stronger (Coduto, 1997) . No evidence of slope instabi1ity exists on the site and adjoining areas including several lots with 1.5:l (horizontal to vertical) cut slopes to 8 feet on the nor~h side of Pine Avenue. Drainage and terracing should be in accordance with the 2010 California Building Code Chapter 18, and the City of Carlsbad Grading Ordinance. At no time should water be diverted onto the slope face in an u~controlled and erosive fashion . Rapid erosion and rutting of the natural slopes could occur, and they should be planted with drought resistant landscaping as soon as possible . 16.0 GENERAL SITE GRADING 16.1 Clearing and Grubbing The area of the proposed fill and gravity wall backfill should be stripped of any existing vegetation and removed off-site or ~tuckpiled ir landscape areas. No boulders over 6 inches should be lefc in c~e fill areas. 16.2 Preparation of Building Pad Areas The p~oposed building addition will encounter loose to moderately dense existing soil to a maximum depth of 2.4-3.2 feet. The area of the proposed development on the west must be overexcavated to firm older terrace macerial and replaced with engineered and compacted fill prior co wall construction. The lot is shown in Lra~sition, and tt1is transition from cut on the north to fill on the south must be mitigated by over excavation to a minimum depth of 3.5 feet to a distance of 5 feet outside the building and gravity wall foundations. .. -.. .. ... 1111 --------... 1111 ... .. .. 1111 .. .. ... ... ... ------------- 12-0808-PL {Sept. 5, 2013 Update) Page 12 16.3 Preparation of Surface to Receive Compacted Fill All sufficiently dense (90 percent relative compaction) surfaces which are to receive compacted fill should be scarified to a depth of 6 inches, brought to near optimum moisture content and compacted to 90 percent relative compaction. Other softer areas must be over excavated to sufficiently dense material and recompacted. Anticipated over excavation and artificial fill removal would be 2.5-3.5 feet in the area of the building and gravity wall foundations. Actual depth of removal should be determined at the time of grading by testing. 16.4 Placement of Compacted Fill Compacted fill is defined as that material which will be replaced in the areas of removal due to root removal, the placement of footings and paving, and also wherever their grade is to be raised. All fill should be compacted to a minimum of 90 percent based upon cte maximum density obtained in accordance with ASTM D 1557-00 procedure. The area co be filled will be prepared in accordance with the preceding section. Fills placed on natural sloces of 5:1 (horizontal to vertical) or steecer will require a key' and benching as shm,m in Appendix C. · 16,5 Pre-Job Conference Prior to the commencement of graaing, a pre-job conference should be held with representatives of the owner, developer, contractor, architect and/or engineer in attendance. The purpose of this meeting shall be to clarify any questions relating to the intent 0 ~ r'na "ra-d0 ] 0 r•q re-on1m6 nd~►'ons aria1 t•O ·•~riCy t'n~~ ·t-~0 ~~c"JJ°C·(•t , L _, • : ' ':/ c. • .. • •• , .• \,, • , "-c;; , , ' <• ,'· I "' , ·• . ; ~ l:., _ ~ L ~ , •·• ':-_ .. ~-I;-' L _. • .... spcc1.r:1cat.1ons comply °\✓ltn recom.rnenaat1ons o.r: this report . 16.6 Testing and Inspection During grading, density testing should be performed by a representative of the soil engineer in order to determine the degree of compaction being obtained. Where testing indicates insufficient density, additional compactive effort shall be applied with the adjustment of moisture content where necessary, until 90 percent relative compaction is obtained. Inspection o and instaJ.la q0.al:i.fied so critical grading control procedures such as keys, ion or need for subdrains, should be made by a ls engineer, and/or engineering geologist. ----- ----··· .. ,. ... ... .. ... -.. .. -... --.. ------------- 12--0808-?L (Sept. 5, 2013 Update) Page i3 16.7 Development Impact ?rovided the recornrnendat ions of this report are incorporated into the design and construction of the residential project, both the proposed development and off-site areas will be safe from geotechnical hazards, 17.0 GENERAL All grading should, at a minimum, follow the ''Standard Grading and Earthwork Specifications'' as outlined in Appendix C, unless otherwise modified in the text of this report. The recommendations of this report are based on the assumptions that all footings will be founded in dense, native, undisturbed soil or properly compacted fill soil. All footing excavations should be inspected prior to the placement of concrete in order to verify that footings are founded on satisfactory soils and are free of lease and disturbed materials and fill. All grading and fill placeme~t siould be performed unde~ the testing and inspection of a representative of the soil engineer . The f:inclinqs and reconunendations of this report ,,Jere prepared in accordance with contemporary engineering principles and practice. Our recommendations are based on an interpolation of soil conditions between boring locations. Should conditions be encountered during grading, that appear to be different than those indicated by this report, this office should be notified . Respectfully Submitted, S. Pat Rymer, RCE 38709 i~eqi.:St.raticn Expires 3-31-2015 S F'R: 1,-; ls Distr·ibution: (3) Adclressee TENTATIVE PARCEL MAP MS 13-03 ~- 1284 PINE A VENUE, CARL~.~AD CA . APN 205-020-04 ·~~-~- @jii~~ ~--~,~:t: . '" i ~L:i;~2UfcJl~\ f-~ ,f \ ; f i Ii : XJSiJ},fi :.i;:Sitl[:o.;.::_f 1! .,,·,~ ; ,. ; ;. F" ·;er.~, ::x ~iMMGC Ii ~I ~- ····:\r 1 --~ i !1•~ ·.' 1/~~:?·· S~~~Tl?N t:i i -A 1' 2 ?t,~Kit.:~, Si":...L$ ·~·"'Tl r···;;-_._ -~!/ i Ii -w1-L~·: .. SJ:_CTJON 1\2·/\2. , -I / ~;· ., .. ,, I ''_JI_ ;; i/-··-.. "\".-·•-- ' frii.._ :...~. --·=1c '···· ·· I i SECTION /\~·/\3° SECTION S; ·81 . OESCl<P1lON STD.OWG. BC>VfOAAY: EXJSrnG CONTOUl PROPOSED CONTOtJa OIRECl10N OF ~CE (12 M.'NMJMI MS.E. + S0RSo FET. WALL= TOPOFWAU. TOP OF FOOffiC BOTTOM OF WALL TCP OF GRATE :,."'IEFIT F1F;l.'ATIO:./ !W CF BW TG IE S™80\. (,:, ... 65 /J.. I l··- ~ ,:'.:\:·-· t··-= ·----~--~ ,~ . ! 1:-2./f~~_;,."' .. Ji·--·-\~~ I.!·· ... -.......... j' .. • . ·---,., ----u ~·~ -··-··· . ·--· SC CT ION 02-82. SCCTION__S-l :,-J:l ?.EC,ION C 1 ·C 1. .( \ r,: -~:.-:1::r..:.;;~_ I~ ~· ;· --------:ii( r cs•, DL II TC Nr,v . L. I MIL I . :(~ LECEfO . ~ ClcOTECHNAL 80ftNO . . :,~~ . GEOTECHNICAL EXHIBIT ....... DRAIN OUTLET DETAIL M>CHAEL C. ~ ______ •.. • _ TPM NO: MS13·03 ASSESORS PARCEL NO A.PN ; 205--020-04 LEGAL DESCRIPTION: LOT g OF TRACT MAP NO. 1744 SITE ADDRESS: '274 PN:. AYENlE. CAALS8AO C/1 SITE AREA/ NO. PARCELS CAOS9 AP.E.A· S.902 SF (OM AC) 1ET NE.A t9.90.2 SF (044 AC.) NO. (P, PFOPOSEO PJ\RCELS 2 PAOPO!:cO PARCEL '1" N::T APcA: 7.517 SF {O 17 AC) PROPOSED PARCEL '2" NET /JR.!:A: ll.565 EF(027 AC) ZONING/GENERAL PLAN: Z~"NG: 'A~,--- CiEHERAL PLAN: FU..M/R\I OUAORN(f, NW i,,tNMU>,4 REac.rneO LOT SIZE> 7.~ SF SEWER DlSTRCT: QTY OF CA.Rl.SBAO WATl:R OlSmCT: CAAI...SBAO MUNJCPAL WATER CISTRCT SCHOOL ~J: CAR..S8Aa U:\'FIED SCHOO:.. D.51'?.Ci SPECIAL OVERLAY ZONES= N COASTAL let£= NO N fl:~LOPMEN'i ZONE NC N YLSITOA ZONE, /'iO MASTER f'l..AN ""°""'E SPEOAC P\.A.N NC(,.E LAND USE PROPOSED NI.A/BER OF PNtCELS 2 EXIS'W-IO L..AND USE: RESIOENTAA.. PROPOSED LA/0 IJSE. RE"°""11AL TOTAL I(). (F-l,l(fS 2 PER LOT (f'pfJJRr + SEC(NJ,'Jr.' owa.1.uc itlT1 ClASSACA'flC>N OF ffiQPOSED LOiS FESD::i'ffiA.L PA0P0SE0 OENS"JY· 9.13 O.U}/'ET AC, uroEVE\..O!"Afl..E f>ER lO.'iNl aD. SEC 2\.53230 NIA COORDINATE INDEX: CAl..JFOAN:A Coc:fOC',IATE r,,OE::t 36M665 OWNER : 12$4 fTE. PAR11-ERS LLC 1284 FN: A'lcffJE. CAR...SSAO CA 9200o (760)58<>-1988 REFERENCE MAPS: IBAC'fMAP NO. 'i744 LEGAL ACCESS FAONTAC'E ON Pl.'I~ A.Vet..;,£; EARTHWORK: Ci.ir:·40·c'i:;··RL;·40·c:-;::·iFET··wALL i:IACXFU:i. FaJECXAL ~ (OVEA·EX + PE.CW.?J\CTl 660 C'r CONSTRAINTS MAP: ····NOr·APPUC.AfLE-·: P'8E'IIOJSLy'QV\oeo S','E'' TOPOGRAPHY: FEBRUAAY'.201,,3 SY KEYN BRESNAHAN Cflfd.. ENONEER .J0.31 ftDGE CREEK OOVE. FAL~ C/1 92028 (95\} 532•6371 DATT: OF PFEPARATION: SEPTEMER I. 2013 BENCHMARK: CIN6/: CAil.Sa..O 'fElmCAI.. CO/'llllOL ~· PONT~ t2'0 STA110N NAME: Cl.SS-120 ELEV.: 06..554 DATU,(. MSL NVGO 1929 PREPARED BY= . ··-···-··-·•---··-··-·-··-----·-~---··-KEVI-I BRES'W-lAN. CiVl. ENCJ:,IEER J03'I ROG€ CREEK DA. FALLBROOK CA 920~ PK(9SI) 532-6:)71 :=:,:,]~If [~;.-r ·6:J=~~4,,f tO:"™'"',~::·:: ~· . -. N G E L .. / ••........ •.1-- i·. <'.> ) SA"1TA -1'+·• ANA _,,.. )·.. 0 R A N G E ·-:vC< ·.f,,. 1933 M 6.3 • •• ~anfa •• CQt<1/i11a ·•. lsfan<I ·· .. ····· ·--~~ -RtGlON~t ~UlT ·."-194 1 • ·f1-K,,.f M5.9-6.0: HIST~RIC M6.0 + EPICE . I ·. _., . . P,"1 1= AvE.., C A"QL.SB Ao w.o . NO: 12-DB06 Pl DATE: ·---- -------1 SITE TERS i 8 0-1998 18 56 octo . .i\EG -J. 9 7 3 ) FIGURE: PLATE 2 ---------... - -----AlPl?lEN])ITX A .. --------- ---------- ---------· --... -.... -... -.. ---.. .. ... -------------- Project Number Project Name Equipment cii ,,..... ~ ·;::: v .., ~ ...J c1.i u ~ .._, :g_ ..c:: .c: a "" t V ... ,:s a c., 1.1.l Geotechnical Boring Log 12-0808-PL Bresnahan CMEB61 ~ VI \0 ~ t (.,_. a. 0 V) .., ~ 0.. 0 ,>-i:o 1'"' ~ 0.. '-' b ·;,; i:: 0 p c Cl Hole Diameter Boring Number Drive Weight 6" B-1 140# 8/17/2012 Elevation Drop 104.5' 30" I § Geotechnical Description I J!(~ · · · · U 'i ,... Logged by: W.L.Sherhng .: \ ~ (.)(/ . ) a ~ (.. /I -·5 'o' a .s ~ Sampled by: W.L.Sherling :;;E ~ -n U ::: 1-'Q. 1 C Ot 1 o ... 7Wf-&.~¥f-~ ~¥#~~~ ~~~3~ t~~~~ ~~~ -~~~~ -~~ ~~~zrw~~~~'f~~~$x~~W'%<}t~~™m~:_~~~~~~~ .... ~~-~~;\~.:~t~ 11 57 I03.6 5 8 SW/S SOIL/COLLUVIUM -Light yellowish brown - 1- 2- 3- 4- 5- 6- 7- 8- 9- 10- 11- 12- 13- 14--- 15- 16- 17- 18- 19- 20- 21- 22- 23- 24- 25- --·--· MD GS El ~ (&7.3 · M 1 OYR 6/4 sl. silty fine to medium sand with minor fine gravel. 0cc. fine clean sand lenses. SI. dense, 6_6 SW/SM sl. damp to dry. Gradual lower contact. SE n 10 !13.8 DS -+-!Lf.,J--l~14,-~t~9~~-.'4t--g--+---+---------------------,! pH Cl MD CON -· - rA 15 k:J 21 GI 19 lJ 24 W 8 ll l 19- rn 14 22 28 117. l (95.7 118.3 (96.7 SW 7.1 7.3 SW 7.8 S\V OLDER TERRACE -Very pale brown IOYR 713 to 7/2 Interhcdded sequence of tlne to medium sl. silty to clean sand. Thin clean sand interbeds 2-4" thick at 6 feet ... _ lnterbeds of sl. gravelly sand at 14 feet+, l-3 " gravel bed common. Dense to very dense 0cc. !cnsc clean coarse sand 2 to 4" thick at 12'·:· . Clean unil'onn medium sand with trace of fine gravel SMfS\V Silty to.sl. silty medium sand -----------------... ---.. --... -... ----------- 'C r.., ~ ..c:: 0. ~ Cl 27- 28- 29- 30- 31- 32- 33- 34- 35- 36- 37- 38- 39- 41- 42- 43- 44- 46- 47- 48- 49- 50- i,j ..., en ·.:: en 0 £ ~ ..J "' -~ ;:E ..... 0 "a .t::: dJ c,: t:: 0. L, "' ~ C, t.:.l ~ .... .., 0. "' :t 0 ~ 22 26 31 ti' c.. ._, 0 ·.;; ::: <.> 0 C' 0 c !::? g u dJ L, E "' ·o ,-. "$. ~ .._, 7.9 6 ·-= ,,,.. ~ (/ ~ (._ ::: ~ Cl 55 u ::: ... Geotechnical Description \ . :>-.~ .-cf:l) Logged by: W.L.Sherling Sampled by: W .L.Sherling 1-'Q. :Lot :L OLDER TERRACE -Light gray I OYR 7i2 to very pale brown 7/4 clean medium to coarse sand as interbeds 1-2 feet thick. SL dense to dense, sl. damp. Minor fine gravel Non-cohesive clean unifonn sand Gravel beds increase to 8-12" 10% of unit overall T.D. 37.6' No Water/ Mottling Severe Caving in upper 15 feet .. --------------.. --------------.. - 1111 .. ---- AJ?J?JENlD [X 18 -------- --... ----- --------------- --- MAXIMUM DENSITY -OPTIMUM MOISTURE DETERMINATION The maximum density was determined in accordance with ASTM Standard 01557-00. The result by full laboratory curve is: Sample Location B-1 B-l Sample B-1 Depth ( Feet) 0-3 Soil Description Maximum Dry Density (Soil Type A) Soil 118.7 Light yellowish brown l0YR 6/4 silty to sl. silty fine sand w/rninor fine gravel (Soil Type 8) Terrace 122.3 Very pale brown to gray brown l0YR 7/3 to 7/2 clean fine medium sand with fine gravel SUMMARY OF EXPANSION TESTING ASTM METHOD D4929 Optimum Moisture 13.9 9.7 Location Depth Expansion Index Expansion Potential 0-4' 0 (-zero) very Low SAND EQUIVALENT TESTING Sanp1e Locat_i_· o_r_, ___ qepth Sand Equivalent B-1 22 -------------------------------------- Direct Shear Test Data Project: Bresnahan Job Number: 12-0808PL Date: 8/20/2012 ··········-·-··----•""·' -~--____ .... ,,. ...... ....: u. d Cl) ui 0. :2 I I IJl t/l Cl) ... ...., (/') OJ .!: ... ro Cl) .c Cf) 5 0 0 Normal Pressure--Kips/SQ. FT. Excavation Number: B-1 Saturated Test 29 .00 Degrees 170 P.S.F. 5 ,, ; ::·~-}-~ .. ___ .-··· .... Depth: 2-4' • Actual Values ; -I3est-Fit • Line ------------ -------------------- --- ti) Cl) IJJ z ~ (.) :r: r- lJJ ..J a.. :;; <! Cl) LL 0 ._. z w 0 0:: ~ I z 0 ._. <! 0 ..J 0 (/) z 0 0 F'REPAREO BY: w . L . s . PRESSURE-KIPS PER SQUARE FOOT t Readings After Solvrotion Wilh Water CONSOLIDATION TEST DATA [XKIIIT NUNl[ft DATE 6/12 .IO(; NUl,lf>ER: \2. 0608 VL I I I I I I I I I I I I <... CD ~ '< ,,, I " ~ ,---"'· ' V'I \ 0 ~ ? .. ~ ~ ~- '!C:i ~ '<:, ~- ~ 1 (;') ' ~ <)° '<:, ... .... "' CS> ;; 0 CD ~ 10) r--::-- N 3J l. fi1 ► .,:.,. m (\ ~ ~ ~ ;> 'v Zrr, ~ Cx ' :t:;i: "-m--1:" f'l~ ::0--; y" 3-" . l d ;t 9orn•i_ I 'I; ... t· : I .• •:" , f i} f !];1-tn·. ,,,1hl+ .-.,-'--~ -o 80 . i1\~tct ;11 fTl ' .JJ, '."! G) :::0 ! +lfft :., ::0 7 fhl:•:·· '': ' )> ~ -:z Z--i 71 ,. (/) :z J1\ N fTl50·_, rri ·+I :::0 • .l,.I CD .. :h 0 -< 40 ·;_ ,-. · : : · · · -l, ... i~~ .. ~ ~ 111-i"H ::0 G) 30:ij: -I -+L CD -J ·,r C 20~·,=::~--+-+~ -1 -::; l 0 z I : l b., ~,11 .. ,11 O' I• !I • 20.0 10.0 .. GRAVEL NO. DEPTH I I I I I I I I I I I I SIEVE SIZES -U.S. STANDARD 8 10 16 20 30 40 ~ I ,if :H ~ l'Ji ,, ri1n .;r1 J H;i I tt; fa! ,! ! i ·1·. ' I ,. } 1l~f:ii·: H!!j:ii rBtl/! {ttL _ : ... l.i.;.L .. [ r> :-~ .: -·.-i-· tii.~t J,t. T. 't.Jl -if t- . '! ii ... . -'--++f.iH;;H+-mm1'i:"!eihHiiH++ l !1:1:. d Hi-' .;, !I ..... l.j I 7-~-,-n11:t· ,·•ti• q·:--n'." t 1 p·~-·J:_Lrt- 80100 200 270 ! I 1 I 1 I I I I I I I I :~LL,!. .. ,.-1--~1' •JI jl •_,_ ---1· '~MtI[fl 1.i.J ..... 1!·:n. 1 i 1 1 I 1l~:::rT1:t-!l l~~:=i i!\in: :1;+1 ' 1IJWWf _iii,! .·.•----1--·~' ~-· ·t1i:• :;, I ·ttl•I ·-~---···i'-1-·_J·- !!j!~ ::ir;D :.1.Hj:n!:fir·!i ·•=! lj ;t 'i •r·~·,. . ci :,·:!:t;c i=~:: ;; Fi' 1·c;·-··1·-'-•·•;. ~ H ! i° ~ ~--· -----~ ,.! .. :, ,., ' , . :;1-r7. ··: ~--.----.--~-'.-· ; ,¥:; 1: :.i::j.::::=: ~ ltt/~-~. ;-. ;.,., ..... , .. , .. U•tl'.,:' • .: .. ; ... · .. : .. : __ ; i'j."it-~t1·1 i.\!1[ :-: ·:::~~; ··I·. •i-, •• .l,.i1·'1•--+ ·------··-•--'.--,~ !h:\'.~F.~Fktii~1-; --------~+- 1.0 0.1 MILLIMETERS .01 .001 PARTICLE DIAMETER B-1 COARSE SAND 0 -3 FT. FINE SANO L.L. _____ _ P. I. SILT UNIFIED CLASS A.A.S.H.O. CLASS CLAY-.. I I -------------... ---AlPJ?lENIDITX C --------------------- -------------.. -- -----.. .. -------------- STANDAlli) GRADING AND EARTI.I\VORK SPECTFIC,o."TIONS These specifications present E.S.I., standard recommendations for grading and earthwork. No deviation from these specifications should be permitted unless specifically superseded in the gcotcchnical report of the project or by written communication signed by the geotcchnical consultant. Evaluations perfom1cd by the geotechnical consultant during the course of grading may resuH in subsequent recommendations which could supersede these specifications or the recommendations of the geotechnical report. 1.0 Gcncrnl 1. 1 'I11e gcoteclmical consultant is the owner's or developer's representative on the project. For the purpose of these specifications, observations by the geotechnical consultant include observations by the soils engineer, gcotechnical engineer, engineering geologist, and those performed by persons employed by and responsible to tl1e geotechnical consultant. 1.2 All clearing, site preparation, or earthwork performed on the project shall be conducted and directed by the contractor under the supervision of the geotechnical consultant. 1.3 The contractor should be responsible for the safety of the project and satisfactory completion of all grading. During grading, the contractor shall remain accessible. 1.4 Prior to the commencement of grading, the geoteclmical consultant shall be employed for the purpose of providing field, laboratory, and office services for conformance with the recommendations of the geoteclmical report and the.so specifications. It will be necessary that the gcoteclmical consultant provide adequate testing and observations so :tl~at he may detcnnine that the · work was accomplished as specified. It shall ·be 1he responsibility of the contractor to assist the geotechnical consultant and keep liim apprized of work schedules and changes so thafhe may schedule his personnel accordingly. · 1.5 It shall be the sole responsibility of the contractor to provide adequate equipment and methods to accomplish the work in accordance with applicable grading codes, agency ordinances, these spccific::itions, and tile ---.. ----.. ... ---... ----------------------- STANDARD GRADING AND EARTH\VORK SPECIFICATIONS.. PAGE2 approved grading plans. If, in the opinion of the geotechnical consultant, unsatisfactory conditions, such as questionable soil, poor moisture condition, inadequate compaction, adverse weather, etc., are resulting in a quality of work Jess than required in these specifications, the geotechnical consultant will be empowered to reject the work and recommend that construction be stopped until the conditions arc rectified . 1.6 It is the contractor's responsibility to provide access to the geotccfmical consultant for testing and/or grading observation purposes. 111is may require the excavation of test pits and/or the relocation of grnding equipment. 1.7 A final report shall be issued by the geotechnical consultant attesting to the contractor's conformance with these specifications. 2.0 SITE PREPARATION 2.1 AH vegetation and deleterious material shall be disposed of off-site. TI1is removal shall be observed by the geotcchnical consult.ant and concluded prior to fill placement. 2.2 Soil, alluvium, or bedrock materials determined by the geotcchnical consultant as being unsuitable for placement in compacted fills shall be removed from the site or used in open areas as determined by the geotc:chnical consultant. Any material incorporated as a part of a compacted fill must be approved by the gcotechnical consultant prior to fill placement. 2.3 After the ground surface to receive fill has been cleared, tit shall be scarified, disced, or bladed by the contractor until it is uniform and free from mts, hollows, hummocks, or other uneven features which may prevent uniform compaction. -- -------..... ...... ------------------------ STANDARD GRADING AND EARTHWORK SPECIFICATIONS PAGE3 The scarified ground surface sha1l then be brought to optimum moisture, mixed as required, and compacted as specified. If the scarified zone is greater than twelve inches in depth, the excess shall be removed and placed in lifts not to exceed six inches or less . Prior to placing fill, the ground surface to receive fill shall be observed, tested, and approved by the gcotechnical consult.ant. 2.4 Any underground strnctures or cavities such as cesspools, cisterns, mining shafts, tunnels, septic tanks, wells, pipe lines, or others are to be removed or treated in a manner prescribed by the geotcchnical consultant. 2.5 In cut-fill transition lots and where cut lots arc partially in soil, coHuvium or unwcathered bedrock materials, in order to provide uniform bearing conditions, the bedrock portion of the lot extending a minimum of 5 feet outside of building lines shall be overexcavation a minimum of3 feet and replaced with compacted fill. Greater ovcrexcavation could be required as detennined by geotechnical consultant where deep fill of 20+ feet transitions to bedrock over a short distance. Typical details are given on Figure D-1. 3.0 COMPACTED FILLS 3.1 Material to be placed as fill shall be free of organic matter and other deleterious substances, and shall be approved by the geotcchnical consultant. Soils of poor gradation, expansion, or strength characteristics shall be placed in area,; designated by gcoteclmical consultant or shall be mixed with other soils to serve as satisfactory fill material, as directed by the geotcchnical consultant. --- -------·· -------------------- -.. .. STANDARD GRADING AND EARTn,vORK SPECIFICATIONS PAGE4 3.2 Rock fragments less than twelve inches in diameter may be utilized in the fill., provided: 1. 1bey are not placed in concentrated pockets. 2. There is a minimum of75% overall of fine grained material to surround the rocks. 3. Tbc distribution of rocks is supervised by the geotechnical consultant. 3 .3 Rocks greater than twelve inches in diameter shall be ta.ken off-site, or placed in accordance with the recommendations of the geotechnical consultant in areas designated as suitable for rock disposal. (A typical detail for Rock Disposal is given in Figure D-2. 3.4 Material that is spongy, subject to decay, or otherwise considered unsuitable shall not be used in the compacted fill. 3.5 Representative samples of materials to be utilized as compacted fill shall be analyzed by the laboratory of the geotechnical consultant to determine their physical properties. If any material other than that previously tested is encountered during grading, the appropriate analysis of the is material shall be conducted by the geotechnical consultant as soon as possible. 3.6 Material used in the compacting process shall be evenly spread, watered, processed, and compacted in thin lills not to exceed six inches in thickness to obtain a uniformly dense layer. 111c fill sball be placed and compacted on a horizontal plane, unless otherwise approved by the geoteclmical consultant. 3.7 If the moisture content or relative compaction varies from that required by the gcotechnical .consultant, the contractor shall rework the fill until it is approved by the geoteclmical consultant. 3 .8 Each layer shall be compacted to 90 percent of the maximum density in compliance with the testing method specified by the controlling governmental agency or ASTM 1557-07, whichever applies. -------------------.. ---------------------- STANDARD GRADING AND EARTifWORK SPECIFICATIONS PAGES If compaction to a lesser percentage is authorized by the controlling governmental agency because of a specific land use of expansive soil condition, the area to receive fill compacted to less than 90 percent shall either be delineated on the grading plan or appropriate reference made to the area in the geotechnical repo1i. 3.9 All fills shall be keyed and benched through all topsoil, colluvium alluvium, or creep material, into sound bedrock or finn material where the slope receiving fill exceeds a ratio of five horizontal to one vertical, in accordance with the recommendations of the geotcchnical consultant. 3. IO The key for side hill fills shall be a minimum width of I 5 feet within bedrock or finn materials, unless otherwise specified in the gcotechnical report. ( See detail on Figure D-3.) 3 .11 Subdrainage devices shall be constructed in compliance with the ordinances of the controlling governmental agency, or with the recommendations of the geotechnical consultant. ( Typical Canyon Subdrain details are given in Figure D-4. ) 3 .12 The contractor will be required to obtain a minimum relative compaction of 90 percent out to the finish slope face of fill slopes, buttresses, and stabilization fills. This may be achieved by either over building the slope and cutting back to the compacted core, or by direct compaction of the slope face with suitable equipment, or by any other procedure which produces the required compactioi1 approved by the geotcchnical consultant. 3.13 All fill slopes should be planted or protected from erosion by other methods specified n the gcotechnical report. 3.14 Fill-over-cut slopes shall be properly keyed through topsoil, colluvium or creep material into rock or firm materials, and the transition shall be stripped of all soil prior to placing fill. ( See detail on Figure D-3.) ---------- - ---·---------.. ------------ ---- 4.0 STANDARD GRADING AND EARTHWORK SPECIFICATIONS PAGE6 CUT SLOPES 4.1 The geotechnical consultant shall inspect all cut slopes at vertical intervals not exceeding ten feet. 4.2 If any conditions not anticipated in the geotechnical report such as perched water, seepage, lenticular or confined strata of potentially adverse nature, unfavorably inclined bedding, joints or fault planes encountered during grading, these conditions shall be analyzed by the geotcchnical consultant, and recommendations shall be made to mitigate these problems. ( Typical details for stabilization of a cut slope arc given in Figures D-3a and D-5. ) 4.3 Cut slopes that face in the same direction as the prevailing drainage shall be protected from slope wash by a non-erodible interceptor swale placed at the top of the slope. 4.4 Unless otherwise specified in the gcotechnical report, no cut slopes shall be excavated higher or steeper than that allowed by the ordinances of controlling governmental agencies . 4.5 Drainage terraces shall be constructed in compliance with the ordinances of controlling governmental ngcncies, or with the recommendations of the geoteclmical consultant. 5.0 TRENCH BACKFILLS 5.1 Trench excavations for utility pipes shall be backfilled under the supervision of the geotcchnical consultant. 5.2 After the utility pipe has been laid, the space under and around the pipe shall be backfilled with clean sand or approved granular soil to a depth of at least one foot over the top of the pipe. 111e sand backfill shall be uniformly jetted into place before the controlled backfill is placed over the sand. 5.3 The on-site materials, or other soils approved by the gcotcchnical consultant shall be watered and mixed as necessary prior to placement in lifls over the sand backfill. -------- .. ------ ---- ------------------- ST AND ARD GRADING AND EARTJT\VORK SPECIJ.i'ICA TIONS PAGE7 : :-ti, 5.4 The controlled backfill shall be compacted to at least 90 percent of the maximum laboratory density as determined by the ASTI D1557-07 or the controlling governmental agencies. 5.5 Fic.ld density tests and inspection of the backfill procedures shall be made by the geotechnical consultant during backfilling to see that proper moistlJre content and unifonn compaction is being maintained. The contractor shall provide test holes and exploratory pits as required by the gcotechnical consultant to enable sampling and testing. 6.0 GRADING CONTROL (5.1 Inspection of the fill placement shall be provided by the geotcchnical consultant during the progress of grading. 6.2 In general, density tests should be made at intervals not exceeding two feet of fill height or every 500 cubic yards of fill placed. This criteria will vary depending on soil conditions and the size of the job. In any event, an adequate number of field density tests shaII be made to·vcrify that the required compaction is being achieved. 6.3 Density tests should also be made on the surface material to receive fill as required by the geotechnical consultant. 6.4 All clcanout, processed ground to receive fill, key excavations, subdrains, and rock disposals should be inspected and approved by the geotechnical consultant prior to placing any fill. It shall be the contractor's responsibility to notify the gcotechnical consultant when such areas are ready for inspection. ---------... --- ---.. --------- - --- - ---- STANDAR]) GRADING AND EARTI-f\VORK SPECIFICi'.\TIQNS PAGES 7.0 CONSTRUCTION CONSIDERATIONS 7. I Erosion control measures, when necessary, shall be provided by the contractor during grading and prior to the completion and constmction of permanent drainage controls. 7.2 Upon completion of grading and termination of inspections by the geotcchnical consultant, no further filling or excavation, including that necessary for footings, foundations, large tree wells, retaining walls, or other features shall be prefonned without the approval of the geotcchnical consultant. 7.3 Care shall be taken by the contractor during final grading to preserve any benns, drainage terraces, interceptor swalcs, or other devices of pennanent nature on or adjacent to the property. --------------- -... ---------------- -· - TRANSITION LOT DETAILS CUT-FILL LOT NATURAL GROUND \_ ---------------5' L _..----_.-.--· MIN. [--: -. -f. CUT LOT NATURAL GROUNC --------------__,. _ --::: REMOVE _ _. __. _ --':)NSUITABLE -------_ _.- ...-:.----MATERIAL _.- UNWEATHERED BEDROCK OR _ ___,/ r-MATERIAL APPROVED BY. f iHE GEOTECHNICAL CONSULTANT NOTE: ~c-;-p~~ ov_ercxcova t ion and recomoac I ion sho! I be p~rform~d 1f de1c:rmmc.d ·o be 0ccesscry by the gcotcc!cniccl consultant. 1-. ---- ---.. ------------- -------------------- BENCHING DETAILS FILL SLOPE FILL OVER. CUT StOPE -- N01ES: To be constrvcted prior 1o fill placement LO'NEST BENCH: Depth end width subject to field change based c., c<Xlsvltcmt's in:spccticn. S~.}~Q HAl~J AGE;. [~·.:"''.:-~: -:'.:-_::,:·1:; f0:::y be re-qui red at I he Ni'r<r·r~t IO(l of th<"" (7("()f("'\nnfrnl rr--..rt";"'llltr1("\~ - ---------... -... ----------- - --- .. ---- 1-&TOI\Y rOOTIHO& OM•AOE DOOi\ 01\AOE •cAM llVlt<Q AMA FLOOI\ &LABO OARAOE FLOOR &LAD$ l'l\(-$0AKIHO Of LIYINO AI\CA AND QAIIAOE eLAI •olLB FOUNDATION AND Sl_AB RECOMMENDATIONS FOR EXPANSIVE SOILS (ON[ AND TWO-STORY TIFSI0OHIAL BUILDll!GS) EXPANSION IHO£X Q -20 VERY LOW EXPAHSIOH _,ll f00flH0$ U OiC~U:'.3 octt. fOOTIHOS Ci;>Hll>IUOVI. HO IHll l\!OUII\ED fOI\ EX,AHltOt< FORCH. -'ll ,ooTIHOS u INCH( s DtEr. fOOTIH0$ COHTIHVOVS. HO STEEL Pl(OUlll[D fOI\ [XPAHOIOH ro11cco. EXPAHSI0H INDEX 21 -60 LOW fXPAHSIOH All roOllHOS 12 IHCHE3 o<o. root11-<os CO+ITIHUQUS. 1-1<0. c IA/I To• MID IOTTOlo<. All fOOTIHOS 11 tHCH(t OHS. fOOTIHOS COKT~UOU$. 1·HO. { I All TO• Al<O IOTTOM. NOY I\EOOfflCb. \2 IHCH£S DE£r. I-HO. C I ~Pl lOt AHO IOTTOU. • 112 IHCt<ES THICK. HO MESH • 1/2 IHCHO THICK, RfOUIRCD f"OR E~rAH,tOH IX 1•10110 WIii( 1.<Clt< AT roRCES. 1(0 ·•ASE "(0Vf<\EO. MIO-HCIOHT. 2 INCHU t J.,U(. Vl3~EH MOt.~'fVRC O~AV(L 01'\ !AHO IAU:. t EXPANSION 11-lOEX 51 -QO MEDIUM -EX:PAHSIOH OTEl\101\ fOOTIMOS U tHCliC3 OE(,-. IHlEl\101\ roOTIKOS 12 IHCHES Ottr. 1-HO. 4 a -'R TO,-AHO t OTTOM. All FOOTIHOS ta IHCHES OEEr, fOOTIHClS COHTIKUOUe, I-HO, A IAII TOS AKO l'OTTOM. U IMCH£3 DEE,-, t-KO; { IAI\ TOr AKO aOTTO ..... 3 1/2 IHCHES THICK. t X 1-10110 WIRE I-ICSH AT MIO-HEICIHT. A IMCIIES 01\AVEL OR SAt<D BA:IE. I IARRfC:R tL03 1 IHCH 3ANO, Mil v1,ouc£H MOCSTV"E WIL Vl30UECH MO~~TURE: OA/1111'11 'HU> 1 INCH SAHO. I ARRIEI\ r LVS 1 IHCl1 SAHO. 3 1/2. 11-!CHU THICK. HO M~>K 3 112 IHCtl(.> THICK. JtEOOIREO FOR [XPA.H:5f0H C X 1-10/lO WU\E UC.1H 01\ fORCE>. HO l-':IE REOU.REO. OUAI\TCR &L,US. !>OLAH HO MOl>TVRE IARAIE" fROM UHi WALL roorn~os. IIEOUIRED. 2 IHCHE> ROCK. ORAVEl OR SAHO IA>E. HO MOISHX\E IARR1£A IIEOUIREO. HOT l\£0UIR.ED. M01$f£K PRIOR TO l'OURtHO CONCRETE. &OAK TO U IHCHES OE!T0H TO 4 'L A I OVE OPTl'-'IJ" I-IOISTURE COHTEHT. ~ 1/2 INCHES THICK. • X 1-10/10 WIRE MESH 011 OVAii TEA 8 LAii :S. ISOLATE f"OM &TCM 'tt-'l.1. FOOTlltOS. -4 IHCHES ROCK. ORAVEL OR SANO BASE. NO MOIHIJAE ~ARRIER REOUlRE04· SOAK TO ,a 1t<CHl::S C>t,-TH TO.,. ABOVE OPTll.4VM 1-1013TVRC COHTEHT. M0f£a: 1) All DErYHS AP.E RElATIYE:TO 4l.Aa 3U8CRAOE. 2) ~l"(Ct.Ail. OE$1<ll< ,:5 ,.;EOVtAEO f'OA VERY HIGHl.Y E.1~AH:'.IVE :SOILS. FOUNDATION ANO SLAB DETAIL (NOT ro SCALE) (XPAHSIOH IHOl;X Q 1 -130 HIOH (XPAHSIOH • C X:l(lfl.101\ fOOTIN0.1 ' ( IH(::1-t(. & Otct. lHTEI\IOI\ roOTIHOS 12 INCHES our. l•t<O. I IAI\ Tot AHO IOTTOU. EXTtl\1011 FOOTIHOS 2◄ l><CHEI OCEr. IHTEl\10 A FOO 1 IHO S 11 IHCH() l>[CP. 1-110. I BAI\ Tor AHO IOTTOU . 2:◄ ,wc~t, DEt ... , .. HO. 6 9AI', TO' .A.HO IOTl'OM. ◄ IHCHES THICi. I X 1-111 WIR( l,l(Stl AT MIO-HCtOHT. HO. 3 OOWELLS FI\OU FOOTIHO lO SLAO _AT 34 IHCHES ON CtHTCll. ◄ IHC>CES OR>.V£L 0~ 8.AHD eA>E. O Mil VISO()f~H UOt,3TUR€: .tU.AAIE:I\ PLU5 t lHCH I.I.HO. 4 U(CHE S n11c,<. I X t -• ,. 'WIRE J.IE'SH 01\ OVA..ATER 8LA8S, ISOLATt FROM SlEM WALL f00T!H0$. 4 IHCHES AOC~. 01\AVl:L OR SAHO l',SE. MO 1-COUT\JRC:: BAA.l'H(R RlOU!A(O. SOAK TO tc IHCHES OErTH TO IT. A0OYE Ol"flLUN MOIS TVRE" COHl(HT.. . FOUNDATION AND SLAG RECOMMENDATIONS JOD NO.: jDAlE: FIOUHE HO.: ---.. -----... -... -... -.. -.. -----------... -------- AlPJPJENDKX TI) -------------.. - ---------------------- APPENDIX G PRELIMINARY GEOTECHNICAL INVESTIGATION SEPTEMBER 20, 2012 W. C. HOBBS, CONSULTING ENGINEER -- -----· ---------------------------------- PRELIMINARY GEOTECHNICAL INVESTIGATION Single • Lot, Residential Development 0.26 +I-Acres, Lot 9, PM 17 44, APN 205-020-04 1284 Pine Avenue, Carlsbad California August 20, 2012 PROJECT NO. 12-0808--PL PREPARED FOR: David Fischbach c/o Kevin P. Bresnahan 3031 Ridge Creek Drive FaUbrook, California 92028-.2690 41659 Date Street, Ste. #202 • Murriet,1, CA 92562 • 8(951) 461-3 l n ,~'..l(951)461·3133 ------------· - ------------ ---------- --- August 20, 2012 Project No. 12-0808-PL 1.0 INTRODUCTION At your request, we have performed a Preliminary Geot.echnical Investigation for the proposed 1 & 2 -story single family residence attached garage and access driveway at the above referenced improved site. The purpose of our investigation was to evaluate the underlying soil conditions with respect to the prop{.>sed development. and to assess the geotechnica l and engineering constraints that might exist considering this development. The 10-scale Site/Retaining Wall Plan prepared by Bresnahan En9ineering, Fallbrook,. dated August 2012 was the basis of our field measurements, and was used to direct ou:r field work. Plate 1 presents our Geotechnical data obtained during our field investigation. At the time of our investigation, the property corners had been surveyed and staked, and the east½ of the site is occupied by an existing residence with fencing on four sides. ACCOMPANYING MAPS, :ILLUSTRATIONS AND APPENDICES Index Map -(2000-scale) -Page 2 Geotechnical Map -(10-scale) -Plate 1 (In Pocket) Regional Fault Map -{l" = 20 miles} -Plate 2 Appendix A -Geotechnical Boring Log Appendix B -Summary of Laboratory Test Results l'~ppendix C -General Earthwork and Grading Specifications Appendix D -References -------.. ---------------- ------------- INDEX MAP ·:~tit(;~,,r-~ ... ·/>~;,:--~'ff·:~~ ·_ ~!~?i~:~'.~:>, ... f!Jtt-,(~;\ ,;J~:~~ ·:\) ~ '\r--·:-~:>~t, .. /~\ f\ \) [:,-\>-·- .~. ,· .-,.,<·)< ·t'L_, .. •,:>•v··11""•'~ l .,,1 ·-el 1·-,. )\ 'I)'• L, .-v '--. ~i}}~f ':{l~~t;)ifc;~ \I~\ l» J x1 r~~~-t} \:iJ.--\ .... ll"~lrr,:mi-H ·/-h:'! • --.;i'>, ~ i•--;~;•,. ~ '·r,•.f< l1i ·-!}. *· )1 ~, = ~ { \~ .? i \V,\} -,,'.,. /; ~ \\_t~l\ .. sv~r~:.fii;Jl~tl f0-)\JJ t:f.J·~~:t.fi\:?,N ;0 \ ·-~,._..1i'..:f,., f \",/;)tYJ \ .. \>•./ :..,·;(,,"'~--.1~'.)f" -~":=;.~1J~-~-_ ........... ,~ f.><:···":::--=--~.; } ,,.1\ \ ; ~--~-;,, "'ltf Cf1nl'C'\l~.,,~· ,l .,._7'• ➔. I I • '\ i -·=f:--· ,. ,.,._,,~, ,_ _,, .. ~p ·( •'~•· -1··· • ' ,, , , .. ,, • ,. ,, !'•· • I -r:'I' ti-• .'f"' ~' I ,,._•-·-~--.. ·t' _·._: f: -~{t:.. .£'-ch ..... ;f.~\~'- '(7-:,,):::i~;:,., .;_;;~t:~:;, 0 2000 SCALE feet INDEX MAP OF 0.26+/~ ACRES, LOT 9, PM 1744, APN 205-020-04 1284 PINE AVENUE CARLSBAD. CALIFORNIA SOURCE: U.S.G.S. 7 ½ MIN. QUAD. SAN LUIS REY 1968 (PR 1975) N -------------------------------------- 12-0808-PL. Page 3 2.0 SITE LOCATION/CONDITIONS The rectangular-shaped 0.438+/-acre property is located on the west side of Pine Avenue, an improved paved ri::,ad in the City of Carlsbad, San Diego County. Pine Avenue bounds the property on the east, with existing houses in all remaining directions. The Index Map (Page 2} presents the topographic and geographic relationships of the property to surrounding areas. Topographically, the existing property in the area of the proposed development has an elevBtion of 105.0 to 111.3 feet. The proposed finished pad is at elevation 107.3 feet. The south side of the lot has a 4-5 foot high 2:1 (horizontal to vertical) fill slope. The lot is draining to the south to Pine Avenue via sheet flow with gradients of 2-4 percent. 3.0 PROPOSED DEVELOPMENT According to the referenced 10-scale Site/Retaining Wall Plan the 0.438+/-acre lot will be subdivided to create a nflag lot" on the west of 0.26+/-acres. Gravity walls to a maximum height of 4.4 feet are proposed on the northr south and west side of the proposed lot. Mi.nor grading for the proposed subdivided lot will consist of cut and fill to a maximum of 3 feet at finished face inclinations of 2:1 (horizontal to vertical) or flatter for the pad and driveway access. Drainage will be to the south via the proposed driveway swale at 1% or less. The existing structure and detached garage on the south will be demolished~ and a new structure constructed. 4.0 SCOPE OF SERVICES The scope nf our: investigation included the following: 1. 3. 4 • 'ft. :revielv Qf available data pertinent to the site. Subsurface exploration of the site utilizing 1 exploratory boring to depths as great as 37.6 feet. The boring was logged. and this log appears in Appendix A of this report. The boring was tested for in-place density utilizing the California Split-Ring Drive ASTM D2216}. Representative bulk samples were obtained £or testing. Laboratory testing of representative earth n~terials to develop soil engineering parameters for the proposed development. Prepacation of this report presenting our findings, conclusions and recommendations concerning site development based upon an engineering analysis of the geotechnical properties of the subsoil as determined by field and laboratory evaluation. ---------------------------... ---------- 12-808-PL Page 4 5.0 LABORATORY TESTING The following tests were performed for thia project in our laboratory in accordance with the .American Society for Testing aJ1<.i ~;faterta.1s., tl1e State ()f Ca.lifornia Standard Specif.icatioris c~r contemporary practices of the soil engineering profession. 5.1 MaY;:j.mum Density -Optimum Moisture. Determinations This test determines the density that a soil can be compacted to at ,Ia:r-icHJ!3 (;<)t1ter1ts .. Fc)r ea(!ll scJil, there is a maximurn dry density obtained and the associated optimum moisture content. The results are used to evaluate the natural compaction, control of the grading process and as an aid in developing the soil bearing capacity. This is based on ASTM Standard 01557-00 (five layer method). 5.2 In-Situ Moisture and Densitv These tests consisted of weighing arnJ measuring dri-...re ring samples from the boring in accordance with ASTI'1 2216. The results are used to analyze the consistency of the subsoil and aid in determining the necessary 9rading to prepare the pad area. 5.3 Sieve Analvsis This test (P..STM D422) determines the mat.er ial grading of the ind:i.v:i.dua1 particle sizes and is Ltsed in generating an engineering classification. 5.4 Sand Equivalent Testinq This is a test (AS'I'M 02419) for the rapid determination of the relative portions of fine silt and clay materials within the soil samples, and is used for a relative comparison of soils in the determination of the adequate paving sections for driveways, etc. 5.5 Expansion Testi.nq The expansic,n index of the soils is determined by the ASTM D4829 and is used to design foundations for anticipated expansion forces. 5.6 Direct Shear A direct shear strength test (ASTM D3080} was performed on a representative sample of the on-site soils remolded to 90%. relative compaction. To simulate possible adverse field conditions, the sample was saturated prior to shearing. A saturating device was used which permitted the samples to absorb moisture while pre'"-renting volume change. This test is used to determine sc>il strengths for slope stability evaluations and for --------------___ ,,,_ - ----------------------- 12-0808-l?L Page 5 foundation bearing capacity. 5.7 Soluble Sulfate A. representzttive surface sample was tested (CTM 417) to determine soluble sulfate content. The test results are used to recommend the type and strength of concrete to be used in construction. 5.8 Soil Resistivity & pH A representative sample was obtained and tested utilizing the CTM 643 test method. The results are use to determine corrosion potential for underc3round metal utilities and facilities. 5.9 Chloride Content The chloride content of representative finished grade soils was tested utilizing the CTM 422 method. The results are used to determine potential corrosion of subsurface soil:3. 5.10 Consolidation An in-situ !:,ample was tested fox-consolidation and collapse utilizing ASTM D2535 procedures. The sample is incrementally loaded to determine compressibility. The sample is inundated with water through a porous stone during testing to determine collapse potential. 6.0 SUBSURFACE CONDITIONS The area of the residential addition is cov,~red by a 2-4 foot thick soil/colluvium. In-place density for the soil/colluvium is 103.6 pcf (87.3% relative compaction) at .5.8% moisture, in B-1 at 1.3-1.B feet, to a maximum of 113.81 pcf (95.9% relative compaction) at 6.6% moisture in B-1 at 3.2-3.6 feet. The underlying Ouaternary Older Marine Terrace was dense to very dense with in-place density of 117.1 pcf [95.7% relative compaction) to ll8.3pcf {96.7% relative compaction) at moistures of 7 percent at depths of 5 -8 feet in B-1. 7.0 GROUND WATER No ground water seepage was encountered on the site to a depth of 37.6 feet. Historic high ground water is expected to be 105-110 feet (elevation 0-5 feet) at the location of the proposed addition based on Miller, Morton, Edington, (1975). No evidence of seepage was seen in the natural or constructed slope faces descending from the property to Pine Ave or on the west side of the lot. ----------------------------------------- 12-0808-PL Page 6 8.0 FLOODING According to the Federal Emergency Management Agency and the County of San Diego, the pad site is not located within the boundaries of a 100-year flood plain. No swales or drainages cross the site and no flooding hazard exists for the pad area or access driv1c,way from Pine Avenue. Runoff is currently directed off-site from the residence to the Pine Avenue via sheet flow and swales. 9.0 GEOLOGY The entire proposed additional building pad area is underlain at depths below 3-4 feet by a Quaternary Marine 'l'errace Miller, Morton, Fife(, 197 5) . No evidence of slope instabil.i ty exists at the site or in the existing cut and fills slopes in adjoining areas to the north and west along Pine and Highland Avenues to a maximum height of 8-10 feet at finished face inclinations of 1.5:1 (horizontal to vertical} or flatter. The site is not included in any State or County fault hazard zone for active faulting. 1.0.0 SEISMIC SETTING/GROUND MOTION PARAMETERS The regional seismic setting is shown on Plate 2. The nearest active faults to the site include the Rose Canyon/Newport Inglewood fault 3.6 km west, the Elsinore fault 31.1 km to the northeast, and more distant, the San Jacinto fault which is located approximately 55.B km to the northeast. The Rose Canyon/Newport Inglewood fault because of its proximity and seismic potential to the site is the design fault when evaluating the site seismic parameters. 11.0 HISTORIC SEISMICITY During the last 100 years in the San Diego County area, the greatest nurr~er of moderate to large earthquakes (greater than 6.0 M) have occurred along the. northern portions of the Newport- Inglewood fault and Whittier Fault {Hileman, Allen and Nordquist, 1974; Peter5on, et all, 1996). The most significant earthquake epicenter within 28 miles of the site was the magnitude 6.3M on the Newport-Inglewood fault in 1933. Several historic earthquakes of magnitude 5.5 to 6.0M have occurred on the Whittier and Norwalk faults historically including the magnitude 5.9 "Whittier Narrows" earthquake in 1987 approximately 42 miles northeast. Several older earthquakes along the southward extension of the Elsinore fault have occurred to the southeast 35-50 miles. ---·••, ------------------- ---·-·-- ------------------------------- 12-0808-PL Page 7 12.0 SEISMIC EXPOSURE Although no precise method has been developed to evaluate the seismic potential of a specific fault, the available information on historic activity may be projected to estimate the future activity of the fault. This is usually done by plotting the l1istoric activity in terms on number of events in a given time interval versus magnitude of the event. Based on such plots, recurrence intervals for earthquakes of given magnitudes may be estimated. A probabilistic evaluation of potential seismicity for the site utilizing FRISKSP (Blake 1998) indicates a 10% probability of exceedance of 0.31g in 50 years assuming all seismic sources. We have utilized strain rates of 3.5 mm/year for the Rose Canyon fault suggested by Peterson, et al {1996), Lindvall &. Rockwell {1995) to estimate the maximum moment earthquake. We estimate the maximum moment magnitude or "design earthquake" for the Rose Canyon fault to be 6.9 magnitude with a 10% possibility ot exceedance in 50 years. This is in agreement with the probabilistic model by Blake, ( 1998} . 12.l 2007 C.B.C. Seismic Parameters: The site coordinates are NJJ.449, W-117.642 Per ASCE Standard 7- 05, E'igures 22-3 and 22-4, the maximum considered earthquake (.MCE) ground motion for the site Class B (5% critical damping) are as follows: Nearest Active Seismic Source (Type B Fault} -3.2km Ss = 1.433 F<'! = LO S~1s = 1 ... 433 SD5 = 0. 956 S1 = 0.513 Fv = 1. 0 8~11 =. 0 ... :)13 SD1 = 0. 342 Per ASCE Standard 7-05r Table 1. the site is classified as Site Class B. 13.0 GROUND MOTION CHARACTERISTICS The 9r:ound motion characteristics which could affect the site during the postulated maximum moment magnitude of 6.9 on the Rose Canyon fault: were estimated. Available information in the literature cLbc,ut maximum peak bedrock acceleration and its attenuation with distance (Joyner and Borzognia. 1994), the effects of site-soil conditions on surface ground motion parameters (Seed & Idress, 1982), and site response criteria 1Hays, 1980) were utilized. -- -······ -----··--- -···----··--- -------------------------- 12-0808-PL Page 8 The predominant. period of bedrock acceleration is expected t.o be 0.30 seconds with 20 seconds of moderate ground shaking {Bolt, 1973). 14.0 SECONDARY SEISMIC HAZARDS The very dense nature of the underlying Quaternary Older Marine Terrace in the area of the proposed addition at depths as shallow as 2-4 feet, and the historic depth to ground water over 105 feet in the area of the proposed addition precludes such secondary seismic hazards as liquefaction, lateral spreading or settlement of the ground the addition is being placed upon. The potential for seismically-triggered landslides is discussed in detail under the slope stability section. 15.0 CONCLUSIONS AND RECOMMENDATIONS 15.l Foundation Design A strip and spread fc>ot ing foundation system should provide an adequate foundation for one and two-story buildings in this site. All exterior footinqs should be founded a minimum of 18 inches below adjacent fini~hed grade for two-story buildings, and 12 inches for one-story buildings. Interior foc,tings m.ay be founded a mi_nimu.m of 12 inches below finished grade. When the footings a.re founded in properly compacted fill or dense soil/colluvium, an allowable bearing capacity of 1500 psf for 12 inch wide footings is acceptable for dead plus live load. This value may be increased. by one-third for short term wind and seismic loading conditions. When foundations are placed in natural soils, no cobbles over 6 inches should be left within the base of the foundation. A typical foundation design is included in Appendix C. Two No. 4 bars, 1 top a.nd 1 bottom is recormuended as a minimum design. 15.2 Settl.ement Our subsurface investigation revealed that the soils beneath the pr1:,posed residential addition are loose so.i.1/colluvium over dense older marine terrace to a depth of 3-4 feet. Footings should experience less than 1-inch settlement with less than 1/2 inch dlf ferential settlements between ,=¼djacent footings of similar sizes and loads when the foundation soils are compacted to engineered f.i.11 standards. This sett.lement is based upon grading of up to 30 feet of fill over a distance of 50 feet horizont.3.lly. If thicker fills are proposed. settlement could be greater and should be ev-aluated prior to placement.. ----------. - ----- ---·-- -------- ------------- -- --- ------ 12-0808-PL Page 9 15.3 Concrete Slabs-On-Grade Sufficient fine-grained materials exists within near surface earth materials to possible create moisture problems. Therefore, we recommend that a moisture barrier be placed under any concrete slabs that might receive a moisture-sensi.tive floor covering. This moisture barrier should consist of a 10-mil polyethylene vapor barrier sandw.iched between a 1-inch layer of sand, top and bottom, to prevent puncture of the barrier and enhance curing (.1f the concrete. Reinforcement of the slabs with No. 3 bars on 24- inch centers mesh centered in the 5 inch slab is recomrnended. The sub grade below-the slab should be moisture conditioned and properly compacted prior to placement of concrete. 15.4 Expansive Soils -So1ub1e Sulfate Expansion testing of near-surface silty sand soils (B-1; 0-4 feet) possible at finished grades indicate that the :3oils in the pad area are very low expansion. No special de:3ign provisions are necessary for the foundation or concrete flatwork to resist expansion forces as shown on the Foundation and Slab Recc>mmendations for Expansive Soils in Appendi>~ C. This is in accordance with the U.B.C. Table 18-B-1. The soluble sulfate content was 125 ppm allowing normal Type II concrete with 2500 psi strength. 15.5 Soil Resistivity & pH The representative subsurface soils anticipated at finished grades were obtained and tested utilizing the CTM 643 test method. The results a.re pH= 7.1 and Minimum Resistivity= 2700 ohm-c:m. No special provisions for bur.i.ed metal utilities or facilities are required. 15.6 Ch1oride Content The chloride content of representative soils was d~termined utilizing the CTM 422 test. method and yielded a chloride content of 145 ppm. No special mitigation for corrosion. of ferrous underground utilities is required. 15.7 Earthwork Shrinkage and Subsidence Shrinkage of the existing soil/colluvium fill will occur during grading, estimated as 4-6 percent when recompacted to compacted fill standards. -- --·-·· ------ - ------- ---------------------- 12-0808-PL Page 10 15.8 Retaining Wall Design Retaining walls should be designed using the following parameters: o Active pressure (level backfill) 49 lb/ft /ft o Active pressure (2:1 backfill) 57 lb/ft /ft o Active pressure (1 1/2:l backfill} 92 lb/ft/ft For purpose of lateral resistance, a value of Q.35 may be used for frictional resistance. A value of 275 lb/ft /ft may be used for passive tesistance for footings placed into properly compacted fill. Frictional and passive resistance may be. combined, provided the later is reduced by one-third. Special loads for dead plus actual loads should be considered in the driveway/parking area that is retained. 15.9 Latera1 Loads Lateral loads in the near-surface soils are: Active At Rest Passive -48pounds per square foot of soil depth (psf/ft) -59 psf/ Et 275 psf/ft (for wood shoring) 350 psf/ft (for concrete footings) Act.i ve means moveme.nt of the structure away from the soil; at re.st means the structure does not move relati.ve to the soil (Such as a loading dock}; and Passive means the structure moves into the soil. The coefficient of friction between the bottom of the foot.inc.JS and the native soil may be taken as O. 35. 15.10 Trench Stabi1ity The near-surface soil to a depth of 5 feet may not stand vertically when excavated. Trenches in excess of 5 feet in depth should have the sides laid back at 1: 1 in accordance with OSHP., requirements. 15.11 Slope Stabi1ity The proposed and existing grading indicates the ma:<.imum. cut and fill slope height is 3-4 feet at finished face inclinations of 2:1 or flatter at the rear and west side of the property. No slopes higher than 4 feet are planned in the area of the proposed addition. The high strength values allow 2:1 (horizontal to vertical) fill slopes up to 30 feet without gross or surficial instability. -------· -----· -----'----- ~ ------------------------ 12-0808-PL Page 11 Selection of Shear Strength Parameters The following shear strength parameter utilized for our slope stability analysis i.,,.•as determined by our laboratory test results as presented below: Material (Cut OF Fill) Anticipated On-Site Fill Friction Angle {Deqree) 29 .. D Cohesion lb/ft2 170 We have utili.zed values of 29.0 degrees and 170 lb/ft2 for older marine terrace natural slopes although it represents a conservative number, determined from a remoldecl. saturated sample. In-situ terrace is expected to be 20% + stronger (Coduto, 1997). No evidence of slope instability exists on the site and adjoining areas including several lots with 1.5:l {horizontal to vertical) cut :3lopes to 8 feet on the north side of Pine Avenue. Drainage and terracina should be in accordance with the 2010 California Building Cod,; Chapter 18, and the City of Carlsbad Grading Ordinance. At no time should water be diverted onto the slope face in an lmcontrolled and erosive fashion. Rapid erosion and rutting of the natural slopes could occur, and they should be planted with drought resistant landscaping as soon as possible. 16.0 GENERAL SITE GRADING 16.1 Clearing and Grubbing The area of the proposed fill and gravity wall backfill should be str:.:i_pped of .~my e:xistin9 vegetation and removed off-site or stockpiled in landscape areas. No boulders over 6 inches should be left in tt"le fill areas. 16.2 Preparation of Bui1ding Pad Areas The proposed building addition will encounter loose to moderately dense existing soil to a maximum depth of 2.4-3.2 feet. The area of the proposed development on the west must be overexca.vated to firm older terrace material and replaced with engineered and compacted fill prior to wall construction. The lot is shown in transition, and this transition from cut on the north to fill on the south must be mitigated by over excavation to a minimum depth of 3.5 feet to a distance of 5 feet outside the building and gravity wall foundations. ------· - - ---· - --- ---------------------.. - 12-0808-PL Page 12 16.3 Preparation of Surface to Receive Compacted Fill All sufficiently dense (90 percent .relative compaction) surfaces which are to receive compacted fill should be scarified to a depth of 6 inches, brought to near optimum moisture content and compacted to 90 percent relative compaction. Other softer areas must be over excavated to sufficiently dense material and recompacted. Anticipated over excavation and artific.i.a1 fill removal would be 2.5-3.5 feet in the area of the building and gravity wall foundations. Actual depth of removal should be determined at the time of grading by testing. 16.4 Placement of Compacted Fi11 Compacted fill is defined as that material which will be replaced in the areas of removal due tc) root removal., the placement of footings and paving, and also wherever their grade is to be raised. All fill should be compacted to a minimum of 90 percent based upon the maximum density obtained in accordance with ASTM D 1557-00 procedure. The area to be filled will be prepared in accordance with the preceding section. Fills placed on natural slopes of 5:1 (horizontal to vertical) or steeper will require a key and benching as .<:,hown in Appendix C. 16.5 Pre-Job Conference !:'r:1.or to the commencement of grading, a pre-job conference should be held with representatives of the owner, developer, contractorr architect and/or engineer in attendance. The purpose of this meeting shall be to clarify any questions relating to the intent of the grading recomniendations and to ver:ify that the project specifications comply with recommendations of this report. i6.6 Testing and Inspection During grading, density testing should be performed by a representative of the soil engineer in order to determine the degree of c:ompacti.on being obtained. Where testing indicates insufficient density, ,::tdditional compactive effort shall be applied with the adjustment of moisture content where necessary, until 90 percent relative compaction is obtained. Inspection of critical gradin-g control procedures such as keys, and installation or need for subdrains, should be made by a qualified soils engineer, and/or engineering geologist. -.. --- - - -------.. -------------------- 12-0808-PL Page 1.3 16.7 DQve1opment Impact Provided the recommendations of this report a.re incorporated into the design and construction of the residential project, both the proposed development and off-site areas will be safe from geotechnical hazards. 1'7.0 GENERAL All grading should, at a minimum, follow the "Standard Grading and Earthwork Specifications" as outlined in Appendix c, unless otherwise modified in the text of this report. The recommendations of this report are based on the assumptions that all footings will be founded in dense, native, undisturbed soil or properly compacted fill soil. All footin<J excavations should be inspected prior to the placement of concrete in order to veri_fy that footings are founded on satisfactory soils and are free of loose and disturbed materials and fill. All aradinq and fill placement should be performed under the testing .,and - inspection of a representative of the soil engineer. T.he findings and recommendations of this report were prepared in accordance with contemporary engineering principles and practice. Our recorrunendations are based on an interpolation of soil conditions between boring locations. Should conditions be encountered dllring grading, that appear to be di~fere.nt than those indicated by this report, this office shou'/ be notified. /·7 Respectfully Submitted, _/ ) , S. Pat Rymer., RCE 38709 Registration Expires 3-31-13 SPR:wls Distribution: {3) Addressee / ; ! I ! 1,,_.J,_,...,. ....... ; ----------------------------------------- %. .. -.. · .. •••••• ~.r ... ,, •• •••• •• /stt,,,,1 ··. .r".: ---.,.~ •• ..... ... . ··············• ... w.o. NO: 12-D0,08 PL ~~~\~'1 ~i..\'.i\'y: ·fl-r~VLl. - f11Sf~RIC M6.0 + EPICE I ·. . .... -·~ . ... C A-Q.i..;;; G A p DATE: B/12 ·---.... .2\EG -1973) FIGURE: PLATE 2 -------- - - - - - ------------------- Projt~t Number Project Name Equipm.ent --CJll ~~ .... ◊ ~ IL' ,...:i iii ~ ·--· ~ .r=: k 0 1- 2- 3- 4- 6- 7- 8- 9- 1 ll- 12- 13- 14--- 15- 16- 17 18- 19- 20- 21- 22 23- 24- 2 Geotechnical Boring Log 12-0808-PL Bresnahan CMEB61 MD GS E! SE Hole Diamett':f Boling Number Drive Weight 6" B-t 140# W.LShl.'Tling 8/17/2012 Elevation Drop P _ 1 cot 1 SOUJCOLLUYUJM. -Light yellowish bmwn 104.5' 30" l OYR 6/4 sl. silty fine to medium sand with minor fine gravel. Oc-c. fine dean sru1d lenses. SI. dense, .. ~v""'M sL damp to dry. Gradual tower contact. b.b :S ,~,"' DS -.-.i--'~'+-..,.,:;:~---+--+--------------------1 pH CI MD CON fil 15 rJ 21 ~ 19 118-3 ZJ 24 (96.7 mii W2s SW 7.l 7.3 SW 7.8 SW OLDER TERRACE -Very pale brown I OYR 7/3 to 7/2 fnt.erbedde-t1 f.equence of fine to medium sl. silty to clean sand. Thin dean sand intcrbeds 2-4" thick at 6 foet +. Interbeds of st grnvelly sand at 14 foet. +, l-3 " gravel bed common. Dense to very dense 0cc. lensc clean coarse sand 2 to 4" thick at t2'--;-_ Clean uniform medium sand with trace of fine gravel SM/SW SHty 10, st silty medium sand ---------------- ,::;, .... Geotechnical Description I ., :;,J_..c;:~--C g_ Q,> -.; ... to .._.. i:l C: 'i' !>A ·.: a:;; .?i: 0 0 Logged hy: W .L.SherHng ' v ✓' ' 0 B t:. ... V .. .:: ~ / ~, \ ...:. ; ,') ' / ,,, ,u-"' ~ ~ 11 r _,, t ~ <> ~ .... t:l. 6 l .,-1j. ' J ._,. ~ 0 ,2 Sc. ;,/ \ I' "• GI '-~ <..t" ..c "' C a '€ ,u ~ V, -~" Sampled by: WL.Sherling =-c.. .Q c· ~B ~ a~-<I:, .... ~ p 0 0 al Q ::;; ;,j, /'Ju:-PO . .2 Ot2: ,...,, 2l -27-OLDER TERRACE -Light gray JOYR 7/2to 22 7.9 -.,-cry pale brolhn 7/4 dean medium to L't)a{Se sand --28-26 as interbeds I-2 reet thick. Sl. dense to dense, sl. 31 damp. Minor fine gravel 29---30-Nnn-.::ohesive clean uniform sand -31- 32--Gravel beds increase to 8-12" HJ% of unit overall 33--34--·-35--36-T.D. 37.6' -37-No Water / M.uttl iog -38-Severe Caving in upper 15 feet .. -39--40---41- -42--43--44. -45M 46- -47-> -48--49--50---- -- ------------- -------------- ------ -- MAXIMUM DENSITY -OPTIMUM MOISTURE DETERMINATION The maximum density was determtned in accordance with ASTM Standard D1 !:i57-00. 'T'he result by full laboratory curve is: Sample Depth Maximum Loca t i_o_·r>_, __ {_E_'e_e_. t_. _} ___ S_c_n_· _l_D_,e_.s_:c_:r_·_i=p_t_i_o_n ____ D_•r_y Densi t v B-1 0-3 B-1 6-7 (Soil Type A} Soil 118.7 Light yellowish brown lOYR 6/4 silty to sl. silty fine sand w/minor fine gravel (Soil Type B) Terrace 122.3 Very pale brown to gray brown lOYR 7/3 to 7/2 clean fine medium sand with fine gravel SUMMARY OF EXPANSION TESTING ASTM METHOD 04929 Optimum Moisture 13.9 9.7 _S_a_rr ..... 1r_1 l_e_. ___ L_,c_1c_a._t_i-'o_n __ D_e_.._o_t_h __ Ex pans i on Index Expansion Potential B-1 0-4' 0 (zero) very Low SAND EQUIVALENT TESTING Sample Loe a t_~_o_n ____ C_Je_-~p_t_h __ f'_:,a_· _n_d_E_q~i_.i_i_v_a_l_e_n_. t B-1 0-4' -------------..... --~ ----------------------- Project: Bresnahan fob Numbt.-r: 12-0808PL D-are; 8/20/2012 Direct Sh_ear Test Data --·~·-··---·-·---------------------------------------------------------------·-····------ --···--·-·-··········-·-~ ----·-···~-~--~--1 i ' 5 --·"'''".'·----·~-~------------.....-~i--~-----,-----, ·. i .. l ..... , ...... ,._, _________ i __ ···-\········-···· ------,.--+----:-~~------} ! ·····--+---------·····-----~------:.---+--._....-_,___-+ __ ..,.... __ J 0 0 5 Normal Pressure--Kips!SQ. FT. ; . ··--------~-~------------~--------------- Excavation Nun1ber: B-l Depth: 2-4' Saturated Test tp = 29.00 Degrees c= 170 P.ST • Actual Values; -----... ----------------------.. --------- PRESSURE-KlPS PER SQUARE FOOT OJ 0.2 0.3 0.5 u, (/) ~ l1J z :s! 0 7: f- w .3 _J 0.. ~ <t (/) lL 0 t-4 z w 0 (C w 0.. I s z· 0 ~ 0 d V, £, z 0 0 • Readings After Solurafil>n With Waler CONSOLIDATION TEST DATA P1tl!!PAft:D e·n w . L. . s ,. f:XKl•tT fl!IUM9Cfll --------0 ---lfJ -0:: w -I-w -0 ~ 0:: <{ _J 0 _J -z ~ <( t-en -a: -(f) w I-::> w -I ~ <:( -fl) 0 w N w -en _J u --w t- > a:: w 'tf. U) ~ --Q ,:0 --- -----g---t-- PER CENT FINER BY WEIGHT -GRAIN SIZE DISTRIBUTION --,m. t'l-06o8f'l .. - 1--..J U) w (1)0 a:z <:! <{ 0(/) u ..J w > ~ a; (!) ; (.I) (/) (/) en <;( <{ ..J ...J u 0 a q w I u.. i.J) -,cf z ::) <i. .J ..J n: ..,_: Lt.. ...:-- Ci) Q 0 z I r 0... w 0 EXH!Bff NUMBER B-4 -- ----------·---- - ------------------ ---- STANDAIUJ GRADING AND J~ARTI1'\'0RKSPECIFI,CATIONS These spectfications present E.S.I., standard recommendations for grnding and earthwork. No deviation from tbe,.sc specifications should be permitted unless specifically su~.rscde.d in the geotechnical re.port of the project or by written comm1mication signed by tlie gootcchnical consultanL Evaluations performed by the· geotechnicaJ c-.onsultant during the course of grading may result in subsequmt recommendations which c.ould supersede these specifications or the .recommendations of the geoteclmical report 1.0 Gencnd J _J The geotechnical consultant is the owner, s or developer ~s representative on the project. For the pmpose of these specifications. observations by the geoteclwical consultant include obsenrations by the soils engineer~ geotechnicaI enginee.r, engineering geologist3 and those performed by persons employed by and responsible to the gooteclmicaI consultant 1.2 AH clearin& site preparatio~ or eart11work per.formed on the project shall he conducted and directed by the contractor unde.r the supervision of the geoteclmical consultant_ 1.3 1ne contractor should be responsible for tbe safety of the projec.t and satisfactory completion of all grading. During gradin& fuc oontractor shaII remain .accessible. 1 A Prior to the oommcncement of grading, the geotedmical consultant shaU be employed for the purpose of providing field. laboratory7 and office services for conformance with the recommendations of the geoteclmical report and these specifications. It will be necessazy trurt the gcotcchnical consultant provide adequate testing and observations so d~at he may determine that tl1e · work was ·accomplished as specified. It shall be the responsibility of the contractor to assist the gootechnical consultant and keep him ~pprizcd of worlc schedules and changes so ~fhe may schedule his personnel accordingly. 15 It shall be the sole responsibility of tlie contractor to provide adequate equipment .and methods to accomplish t11e work in ac-.("-Ordancc.~ with . applicable grading codes, agency ordinances, these s_pe-.dfications, and the ----------- - -- ------.. ---.. ------:-· ---- STANDARD GRADING AND EARTIIWORK SPECIFICATIONS PAGE2 approved grading plans. lf, in the opinion of the ge.otechnical consultant) unsatisfactory conditions~ such as questionable soil~ poor moisture condition~ inadequate compaction~ adve.rse weather, etc., are resulting in a quality of work foss than required in these specific.ation."S, the geote.chnical consultant will be empowe-.red to reject the work and recommend that construction be stopped until the conditions arc rectified. 1.6 It is tbe contractor's responsibility to provide access to the ge-0te.dmicai consult.ant for testing Md/or grading observation purposes. 1bis may require the excavation of test pits and/or the relocation of grading equipment. l. 7 A final report shall be is .. <{lled by the geotechnfoal consultant attesting to the contractor's confornranc-.c with these spee-i:ficati.ons. 2.0 SITEPREPA.RATION 2.1 All vegetation and deleterious material shall be disposed of off-site. This removal shall be observed by the geotechnfoal consultant and concluded prior to fill placement 2.2 Soil, alluvi~ or bedrock materials determined by the geotechnical consultant as being unsuitable for placement in compacted fills shall be removed from the site or used in open areas as determined by the gcotccbnical consultant. Any material incorporated as a part of a compacted fill must he approved by the geotecbnical consultant prior to fill placemcnL 2.3 After tbe ground surface to receive fill has hren cleared,, tit shall be scarifi~ disced, or bladed by the contractor until it is uniform. and free from nits~ hoUoWS; hununocks, or otl1er uneven features which may prevent uniform compaction. ----------- -.. ---.. ----- STANDARD GRAJ)ING-AND EARTHWORK. SPECIFICATIONS PAGE3 The scarified ground surface shaU then be brought to optimum moisture-., mixed as required, and compacted as specified. If the scarified wne is greater than twelve inches in depth., the excess shal1 be removed and placed in lifts not to excce.d six inches or less. Prior to placing fill,, the ground surfhcc to receive fill shall be observed, tested,. and approved by the geotechnical consultant. 2.4 Any unde.rground stmcture.s or cavities such a-, cesspools, cisterns, mining shafts!> tunnels~ septic tanks, wells, pipe. lines, or others are to be retuoved or treated in a manner prescribed by the geotechnicru consultant. 2.5 In cut-fill transition lots and where cut lots are partially in soil, colluvium or unweathered bedrock materials, in order-to provide uniform bearing conditions, the bedrock portion of the lot extending a minimum of 5 feet outside of building Jines shall he over-excavation a minimum of 3 feet and replaced with c.ompacted fill. Greater overexca.vation could be required as determined by geoteclmical consultant where de.ep fill of 20+ feet transitiQns to bedrock over a short distanc-.e. Typical details are given on Figure D-1. • 3.0 COMPACTED FILL.~ --------.. ----- 3.1 Material to be plnf'.ed as fill shall be free of organic matter and other deleterious substances, and shall be approved by 1he geotechnical consultant. Soils of poor gradation_. expansio~ or strength characteristics shall be placed in areas designated by gootechnical consultant or shall be mixed with oilier soils to serve ns satisfactory fill materia4 as directed by the geotecbnic.al consultant. ..... ~-----.. ---- ---- ------------.. - - --------------.. ------ STANDARD l-:;RADING AND EARTR\VORK_ SPECIFICATIONS PAQ.E 4 3.2 Rock fragments less than twelve inches in diameter may be utili:zcrl in the 1111, provided: 1. ·n1ey arc not placed in concentrate-cl pockets. 2. There is a minimum of 75% overall of fine grained material to surround the rocks. 3. 'lbe distribution of rocks is supervised by the geotecbnical consultant. 3.3 Rocks greater than twelve inches in diameter shall be taken off-site, or placed :u1 accordanc..c -with the recommendations of the geoteclmic-al consultant in are.as designated as suitable for rock disposal. (A typical detail for Rock Disposal is given in Figure D-2. 3.4 Material that is spongy, subject-to decay, or otherwise considered unsuitable s~U not be used in the compacted fill. 3.5 Representative samples of materials to be utilized as compacted. fill shall be analyzed by the laboratory of the geotechnic.al consultant to determine their physical properties. J.f any material other than that preyiously tested is encountered during grading. the appropriate analysis of the is material shall be conducted by the geotechnical consultant as soon a~ possible. 3-.6 Material m,ed in the compacting process shall be evenly spread. wate.red, processed, and compacted in thin lifts not to exceed six inches in thickness to obtajn a uniformly dease .layer. The fill shall be placed and compacted on a horizontal plane~ unless otherwise approved by the geotcchnic.'11 consultant. 3.7 If tlie moisture content or relative compaction varies fto.m th.at required by the geotecbnical -eonsu:ltant, the contractor shall rework the fill until it is approved by the geotechnical consultant. 3.8 Each layer shall be compacted. to 90 percent of the maximumdc.nsity in compliance with the testing method specified by the controlling govemme.ntaI agency or A.STh11557-07, whichever applies. ------------------- ------------------ STANUARD GRADING AND EARTHWORK SPECIFICATIONS J>AGE 5 If cumpaction to a Ie.ssc-.r percent.."'lge is authorized by t11c controlling governmental agency because of a spe.cific land use of expansive soil <xmdition:o the area to rec-.cive fill compacted to less than 90 percent shaH dtlier be delineated on the grading _plan or appropriate referenc-..c made to the area in tl1e ge.oteclm.icaJ report. 3 .9 A11 fiUs shall be keyed and benched through a.U topsoil, colluv.ium alluvium, or creep material, into sound bedrock or firm material where the slope receiving fiil e.xceeds a ratio of five horizontal to one vertical, in accordance with tbe recommendations of the ge.oteclmical consultant 3 .10 'I11e key for side hill fills shall be a minimwn width of I 5 fee-.t within bedrock or firm materials~ unless otherwise specified in the geotechnical report. ( &x; detail on Figure D-3. ) 3. I l Subdrainage devices shall be constructed in compl.iancc with the ordinances of the controlling governmental agency~ or ·with the recommendations of the geotecbnical consultant. ( Typical Canyon Subdrain details are given in Figure D-4. ) · 3.12 The contractor win be required to obtain a minimum relative compaction of 90 percent out to the finish slope face of fiJJ slopes~ buttresses~ and stabilization fills. This may be achieved by either over building the slope and cutting back to the compacuxl core_. or by direct c.ompaction of the slope fuce with suitable equipment,-or by any other procedure which produces the required compaction approved by the geotechnical consultant · 3.13 All fill sJopes should be planted or protected from erosion by other me1hods specified n the geotcchnical report 3.14 FiU-over-cut slopes shall be properly keyed through topsoil, colluvium or creep n1an...ml into rock or £um materials,. and the transition shall be stripped of all soil prior to placing fiH. ( See detail on Figure D-3. ) ---..... . ----- ------------------------.. - -- STANJJARD GRADING-AND EAI{Tlf\~1ORK SPECIFIC,A TIONS PAGE_(! 4.0 CUT SLO~_ES 4.1 The geotcchnical c-0nsuitant sbaU inspect a.lJ cut slopes at vertical intervals not exceeding ten feet 4.2 If any conditions not anticipated in the geote.chn.ical report such as perch~.d wdt.er> seepage, lenticular or con.fined strata of potentially adve.rsc nature:1 unfuvombly inclined bedding, joints or fault planes encountered during grading, these conditions shall be analyzed by the &>eotechnical consultant. aud recommendations shall he made t.o mitigate these problems. ( Typical details for stabilization of a cut slope are given in Figures D-3a and D-5. ) "1-.3 Cut slopes that face in the same direction as the prevailing drainage shall be protected from slope wash by a non-erodible interceptor swalc placed at the top of the slope. 4.4 Unless othenvise specified in the gootechnicaJ report,. no cut slopes shall be excavated higher or steeper than that allo,vcd by the ordinances of controlling goVt."1.ml1ental agencies. 4.5 D..rainage terrac.es shall be constructed in c-0mpliance with the ordinances of oontrolJing governmental agenci~ or with tf1e recommendations of the geote<:'lmical consultant 5.0 TRENCH BACh..7FILLS 5_ 1 Trench excavations for utility p~ shall be backfilled under the supervision of the geotechnical consultanL 5.2 After the utility pipe has been laid_. the space under and around the pipe shall be backfilled with clean sand or approved granul~ soi1 t.o a depth of at least one foot over the top of the pipe. The sand backfill shaH be uniform]y jetted into place before the controUed backfill is placed over the sand. 5.3 The on-site materials, or other soiJs approved by the goote.chnical c-0nsultant shall be watered and mixed as necessary prior to placement in lii"ts over the sand backfill. ----------- ---·----------------•• ------ STANDARD GRM)JNG AND EARTHWORK SPECIFICA TJ.ONS PAGE 7_ . .:-/• 5 A ·111e con1ro11ed backfill shall be compacted to at le-.ast 90 percent of the rnaxiinum laboratory density as determined by the ASTI D1557-01 or the controlling governmental agencies. 5.5 Field density tests and inspection of the hackfiU procedures shall be made by the geotechni("'.al c.onsult.aut during bac-kfimng to see that pro_pc.r moisture content and uniform compaction is being maintained. TI1e c.ontractor shall provide test holes and exploratory pits as required by the geoteclmical consultant to enable sampling and testing. 6.0 GRADING CON'rn.or., (j. J Inspection of the fiU placement shall be provide.cl by the geotcchnicaI consultant during the progress of grnding, 6.2 In general~ density tests should be made at intervals not exceeding two feet of fill height or every 500 cubic yards of fill plac.ed. This criteria win vary de.pending on soil conditions and the size of the job. In any even~ an adequate number of field density tests shaU be made to·verify that the required c-.ompactfon is being achieved. 6.3 Density tests should aJso be made on the surface material to receive fill as required by the geotecbnical consultant. 6.4 AH cleanout, processed ground to receive fill, key excavations, subdrai.ns, and rock disposals should be inspected and approved by the g:eotechnical consultant prior to placing any fiJL It shall be the contractor~ s responsibility to notify the geoteclmical consultant when such areas are ready for inspection. ---..... . ----------------------------------- ST;\NDARD GRADING AND EARTffiVORK SPECilrJ.CATTONS PAGES 7.0 CONS'l'R.UCTION CONSIDERATIONS 7.1 Erosion control measures. when necessary, shal1 be provided by the contractor during grading and prior to the comple.tion and constmction of pem1auent drainage controls. · 7.2 Upon completion of grading and termination of inspections by the geotechnical consultant, no furt11er filling or excavation, including that necessary for footin~. foundations, large tree wells, retaining walls. or othe.r features shall be preformed without tl1c approval of the geoteclmical consultant. 7.3 Care shal1 be taken by the contractor during final grading to preserve any berms, drainage terraces, interceptor swales, or other devices of permanent nature on or adjacent to the property_ ---------------------.. -.. ----- -------- TRANSIT[ON LOT DETAILS CUT-FILL LOT ----------- ------------------- --- NATURAL GROUND 1~ ----_ __, 5' L_ MIN.! t UNWEATHEREO BEDROCK OR -I ~ MATERIAL APPROVED BY ~ f THE GEOTECHNICAL cqNSULTANT CUT LOT NATURAL GROUNI ~ . --------------...---. ----,,---...-~· -_ -....-REMOVE -- ---·· · ~':JNSUITABLE---.,_ ,;.,_ -- -~ -MATERlAL __. ____,f NOTE: · Deeper ovec-excovotionond recornooction shall be p~rform~d . if de:!crmincd ~o be .neces.scry by the: geotec~nicc{ consuhon1- --BENCHING DETAILS ---------.. , .. --- -- --------------- -.. ----NOTES: -LOWEST BENCH: Depth end width subject to field change · bose<l c-.:-1. C<Xl5Uitant".s inspection. -S~B D RA 1: ~AGE.: -e ,:-<-:-~: -=.:--_:;~·,:; r.tc.y be rcqui re-tl o t the --i~-c:.-r,..tino Of th,... n.--ot<"'.t-:nnicn\ ,nn"uiton.,. ----------------------------- - ------ OA.l!J.<.J(;. i,0,011; 0.IIJ.0£ •£Mi U.VlHO AfrEA n.~ .&t.l\11-3 FOUNDATION AND SLAB RECOMMENDATIONS FOR EXPANSIVE SOILS (ON£:' 1-,ND TWO-STORY Rf.:SIOD{TlAl mUlOlNGS) .E.1.:PAKSIOI< 11roci: " -t(J VCRY LOW EY.PAN.SIOH #.U. fOOTIKOI •~ 01-l<;tt,;:o l>t£,._ f"001U<Q$ i;QHUH-1. kO .&UH 11,!00U\!O-FO" l.:U';O.Nll'!»! f"O!V;:t::.&. 14,'-rooTIHIU ,. l>fCltt:O l>Ur. f-C..OTlt<<U eotn'IHU()CA. M<'.> ST[[t. ~EO<JlftUJ fl>ft £Xl'liHcllOK f"O~C.£!$. -' It: ~KEI TlflCK. t<O ~IH 11£«1ffi!EI, Hffl t;,:,-AiQl()fl; FO!tGt"II, HO 011'A.II; 11£«.l,Rl'I>. f $0\. Yl-'SOUCEH lol:~ill'Ui\C ...... ~ .. Fl.tr) 1 IHCH aum. EXl>AJ.(S!OH IN:Dl:'X :H -i!iO UlW E)(PAU.S!Ot! 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'W'IS<WEEH MOUi~( l>A.ftfUC,. re.us t t..ie>i &.um. £ )::I' AffS!OK mo£ l(. 111 -t:ao HIOH D'.!>ANS!OH,. £•101101!. fOOl"!WJ:l H lN{".l<fc1 Ol;H. l'ClU\IOI\ t001 mo~ U IH(;H(.S bf'.EP. 1--110. I ....... Tor .ANEI •QT"T<,..,,.~ (li(f(ft$0A f(IOTIHO<I H IMCH£l r.££t. lHTF.<UOl'I. roon>10~ •• INCfft;!I t,("f;P_ t---t<O. J a>.r, TOI' AM> •ono ... U lm:-H~~ J>Ef;J'. I-HQ_ O II.All; TOI' .I.HO totTou_ ~ &!'CKt!I "tlffi::i.:. • J! t•Hl 'll'nll: .,aH ;( l M10-H£1GffT. l<O. ~ l><)WU.l.'3-l'l'\01.1 FQOTIH/l TO :51.1.fi AT le~ INCi<£~ Ot< Cl;kTV{. ~ IHCHEI UtU,v:£1. Oft il.1-NO IIJA-S~ f. WI. Vl30<JUi'.!< M()t,TUIIS: U.ME,. l"l!J'1 l IHl.;H f-.1.l(O. aA.JU,<l~ .-LO<II\ lUfll ~ il7.~$ TfflCIL HO MESI< :, 112 ~HES l"441Cf(. c; Y:l jff(:ttES TffiCf:... ~ IMCHCll 1MK:llt. C X t-U• ftE(M)fflEC, f"Ol!c l!:Xf'AU:SOO>< " lt ♦-tol-.0 -Ee 111'.$1< 011 -f X t--10'10--Ea ME'SK 011. WIM.. l;({.Jfl OIi WAl'ITEI< l"01'CE"-MO 1-Mlt ftECIUdltO. O<tAl'ifl'.ll t;t.A.&._ taOVJII:. OIMIITE-'! -llt..t.lJ~ ISOLATE; 8.lABl-. !SOI.ATE tllOM •nu• J10 w,nni'1!1:: t:.t.lllUtll ~ &TE .. ~ J"OOTINO~ !'AO,,, $TEM; Wl,U. ,-ooTtHOS. WI\U. J"OOTIOl<U. C ll'fl;Hl:S l'll;<Rl$1\£D. ~ ~$ IIIOCO:.. U.Mvtl 011 -' tHCJIE-S Roe.c. (U\.\V-Cl. -l'IGC1t.. a.!IA.Y£l or, $__.._ IIJA.U'.. ""-.,.._,£, HQ NOISTl.llf>£ ""'10 il!-M£.. tlO MOISl"fffle KO MO<l!.TIME ""-"""'" """"'"'"-l'lil:.<Wtfl(O, ill,\IU!.!El'< 1'1£QUlR£0.' J\£-0, l'l'IC-$0A.lUHO OF t..J'llfl(j 11101 R£00!RED. UOUT£l< •oA~ T-0 n IHCHE.I fJE!'"l_H ll04Y. TO ... lff,C:tu:a ou•TH &-o.u; TO U INC.«_:C:. i>E;~Tlt lO A.f!C4 AHO OliJV.-OE. &LU ,111~tor~o TOCol'<-1.10¥:£01'~ TO liS. >.aOVE 00-TII.IUM ""-#.tOVE _,_ ~"tlJ>I£ •01>..• C:ONeftf;TE. ~'WIIE c.o,non_ uoi:itUR£ eoinan. (: o«ttH-r_ - "Ol"t:.I: l} #,.U. D!:l"TIC:S ,1.,iE .R£LI.TIV!<l0 •LA& 5U'8Cff,li:J(. 0 ll'fCV.L ta£S.10/i l$ RC0\1111£0 H1#t \'"£ft>' NIGHl. 'I" u:rAHSIV£ &o«.S.. FOUNDATION AND St.AB DETAIL {ttOT TO $CME} -l!U,I Wl'0.11'-01; ...,,u. ~f. SOU££.►.• t>OW-U. {wtlEK MQ!Jll\£0) :i:1.A J Jl'-'l'H .. O" .s•"" •"$~ IWt!E>t f>aE<:l\111'<£0} Q~ ~ ~J;- • :1~-"""'..-.:'---...... '"'----'---'"- .... -~t- tvmrn;rn:-.·R~ FOflCl~O .... fl • <.J; tal"I' Tit Of' E~ftEO\!tllEO} IH1"£1<11)JI; ~ ~~F°o i ... ~,~--;~lOAICV> l'OOIIKO ' __ _L ~if~~ -~~ ... _________ P<"tl'.NO"·roonom: ____ _ __ UC'U:111011. l'OOllM<l: FOUNDATION AND SLAB RECOMMENDATIONS JOB NO.:. FIGURE t{O.: - ---------------.. --------- - --- - -- PUBLISHED REFERENCES Blake, T.F., 1998, Computer Services Software, A Computer Proi;iram for the Probabilistic Evaluation Horizontal Acceleration from California Faults, FRISKSP, July 1998 Blake, T.F.r 1998, Computer Services Software, A Computer Program to Determine Historical Seismicity from Digitized California Faults, ErJSEARCH, ,July 1995 Boltf B.A., 1973, Duration of Strong Ground Mot.ion: Proc. Fifth World Conference on Earthquake Engineering, Paper No. 2927 Clark, M.W., Harms, K., et al., 1984, Preliminary Slip-Rate and Map of Late-Quaternary Faults of California, U.S.G.S. Open-File Report 84-106, 12 p. Coduto, D.P., 1997, Down to Earth Soils Erv;ineerinq, vol. 4, Slope Stability, Cal. Poly Pomona University. Edington, W.J., 1973, Geology of the Dana Point Quad. Orange County, California, California Division of Mines & Geology. Preliminary Report Map 1:12,000 Hart, E.W., 1998, Fault Rupture Haza.rd Zones in California, C.D.M.G. Special Report No. 42, 25p Hays, W.W., 1980, Procedures for Estimating Earthquake Ground Motions, U.S.G.S. Professional Paper 1114, 77p Kennedy, M.P., 1977, Recency and Character of Faulti.ng Alon9 the Elsinore Fault Zone in Southern Riverside County, California, C.D.M.G. Spec. Report 131, 12 pages LindYall, S.C., and Rc,ckwell, T.W.,. 1995, Holocene activity of the Rose Canyon fault zone in San Diegor California: Jour. Geophy::-.ical Research, v.100, p. 24r 121-124, 132 Miller, R.V., Morton, P.K., and Fife D.L., 1975, Geo- Environmental Maps of O.ran9e County, California, 1973, California Division of Mines & Geology, Preliminary Report 15 Peterson,M.P., Bryant, W. A., Cramer:, C.H., Reichle, M.S., 1996, Probabilistic: Seismic Hazard Assessment for the State of California, C.D.M.G. Open-File Report. 96-08 Seed, H.B., and Idriss, I.M., 1982, Ground .Motion and Soil Liquefaction During Earthquakes, E.E.R.I. Nomograph, 134p, Berkley Press Slernmons, D. B., 1977, St.ate-of-the-Art for Assessing Earthquake Haza.His in the United States, Army Co.rps of Engineers, Misc. Papers, S-73-1, Report 6, Fault and Earthquake Magnitude, 240p