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Home My WebLink AboutPD 2021-0033; 3357 ADAMS STREET; LIMITED GEOTECHINCAL INVESTIGATIONS PROPOSED NEW ATTACHED BUILDING ADDITIONS EXISTING RESIDENCE; 2022-01-20Project No. FC-21-07-145 January 20, 2022 Dr. Shane Garst 3357 Adams Street Carlsbad, California shanegarst@gmail.com SMS GEOTECHNICAL SOLUTIONS, INC. Consulting Geotechnical Engineers 5931 Sea Lion Place, Suite 109 Carlsbad, California 92010 Office: 760-602-7815 smsgeosol.inc@gmail.com Addendum Geotechnical Letter, Minimum Asphalt Concrete (HMA) Pavement Structural Section, Proposed New Additions And Renovations, Existing Residence, 3357 Adams Street, Carlsbad, California Specific asphalt concrete (HMA) pavement designs can best be provided based on R-value testing of the actual finish subgrade soils. However, the following recommendations, and minimum pavement structural section based on subgrade R-value of 5 and traffic Index {TI) of 4.5, are appropriate and may be considered, unless otherwise noted or superseded by actual testing: 1. A minimum pavement section of 4 inches HMA (AC) on 6 inches of Class 2 aggregate base (AB), or the minimum structural section required by City of Carlsbad, whichever is more, may be considered. Actual designs will depend on final subgrade R-value and design TI, and the approval of the City of Carlsbad. 2. In the areas where the longitudinal grades exceed 10%, 0.3-inch asphalt concrete (HMA) should be added to the design asphalt thickness for each 1 % increase in grade or portion thereof. PCC paving should be considered for longitudinal grades over 15%. 3. Maximum lift for HMA (AC) shall not exceed 3 inches. The 4-inch asphalt concrete layer should consist of 2.5 inches of a binder/base course (¾-inch aggregate) and 1.5 inches of finish top course (½-inch aggregate) topcoat, placed in accordance with the applicable local and regional codes and standards. 4. The Class 2 aggregate or recycled base (AB) shall meet or exceed the requirements set forth in the current California Standard Specification (Caltrans Section 26-1.02). Base materials should be compacted to a minimum 95% of the corresponding maximum dry density (ASTM D1557). Subgrade soils beneath the asphalt paving surfaces should also be compacted to a minimum 95% of the corresponding maximum dry density within the upper 12 inches. Base R18 Cl077 03740 E329 AASHI □ ACCR E OITEO Addendum Geotechnical Letter, Minimum Pavement Structural Section January 20, 2022 3357 Adams Street, Carlsbad, California Page 2 materials and subgrade soils should be tested for proper moisture and minimum 95% compaction levels and approved by the project geotechnical consultant prior to the placement of the base or asphalt layers. If you have any questions or need clarification, please do not hesitate to contact this office. Reference to our Project No. GI-21-05-131 will help to expedite our response to your inquiries. We appreciate this opportunity to be of service to you. SM§ Geotechnical Solutions, Inc. Distribution: Addressee (1, email) Michael Leeper, ( email) SMS GEOTECHNICAL SOLUTIONS, INC. §JI§ GEOTECHNICAL SOLUTIONS, INC. Consulting Geotechnical Engineers 5931 Sea Lion Place, Suite 109 Carlsbad, California 92010 760-602-7815 smsgeosol.inc@gmail.com Project No. FC-21-07-145 November 5, 2021 Dr. Shane Garst 3357 Adams Street Carlsbad, California shanegarst@gmail.com Geotechnical Plan Review Update and Response to Third Party Review Comments, Gant Residential Additions, 3357 Adams Street, Carlsbad, California The project most current Grading Plans, prepared by Mike Leeper, PE,. dated September 16, 2021 for the proposed building additions at the above-referenced property, were provided to us for review and comment A copy of the project plan (sheet 3 o°f 7) is reproduced herein and included with this report as a Geotechnical Map, Figure 1. Project foundation plans and details, prepared by TREngineering, last dated September 6, 2021 were also provided to us for our review comments. We are also in receipt of a "Third-Party Geotechnical Review (First)" of our report (referenced below), prepared by Hetherington Engineering, Inc. dated October 8, 2021. A copy of the Hetherington Engineering, Inc. review letter is attached herein as an Appendix. Reference is made to the following reports prepared by this office in support of this project: Limited Geotechnical Investigation Proposed New Attached Building Additions Existing Residence 3357 Adams Street Carlsbad, California Project No. GI-21-05-131, June 14, 2021 The referenced reports are on file with our office and copies can be obtained upon request. The pwpose of this effort was to review the project most current Grading Plans (Figure 1 }, and I &Ill .,. • I 1111 1111 1111 Ill Ill PII 1111 : • • • Ill ■ ■ • GeotecbnicaJ Plan Review Update and Response to Review Comments Garst Residential Additions, 3357 Adams Street, Carlsbad, California November 5, 2021 Pagel foundation plans and details from a geotechnical engineering viewpoint, and confirm their compatibility with the site indicated geotechnical conditions and recommendations given in the referenced report. Updated/added recommendations and clarifications to the third-party review comments are presented in the following sections. I. SITE DESCRIPTION/ GEOTECHNICAL CONDITIONS Geotechnical conditions remain substantially the same as presented in the reference report. Detailed descriptions of the underlying subsoil profile and geologic units at the project property are provided in the referenced report. Approximate location of exploratory test pits, as well as distribution of the underlying geologic units, are transferred and depicted on the attached Geotechnical Map, Figure 1. Pertinent geotechnical data and engineering properties of the underlying soils are provided in the referenced report. New updated Geologic Cross-Sections A-A' and B-B' depicting existing/proposed grades and site subsurface profile are included as Figures 2 and 3. However, remedial and pad grading work are now mostly completed for the attached building addition portion of the project (remedial and pad grading is not yet carried out for the proposed covered carport). Completed earthwork, within the limits of current grading areas, have generally achieved final design grades and configurations shown on the project grading plans (Figure 1 ). All completed grading work were carried out under geotechnical engineering observation and compaction testing services provided by this office. All upper loose and compressible soils were removed to the firm native ground, as approved in the field, moisture conditioned to near optimum levels, throughly processed and mechanically compacted to at least 90% compaction levels. A final grading compaction report will be prepared and forthcoming upon completion of remedial grading work for the covered carport and concrete driveway. There is also an existing soil stockpile on the western property margin as shown on the attached Figure 1 . II. PROPOSED BUILDING ADDITIONS AND iMPROVEMENTS Based on our review, project most current plans substantially propose a similar concept, as it was anticipated, and considered and used as a basis of our original study. Proposed building addition pad and finish floor elevations have remained substantially unchanged and significant cut-fill grading and ground modifications are not proposed. Project earthwork operations mainly consist ofremedial bearing and sub grade soil preparation efforts and minor filling/fine grading to achieving final design grades and establish positive drainage away from the building foundations. A minor 2: 1 maximum gradients fill slope, on the order of 3 feet high maximum, will provide ground transitions around the western new building addition/carport pad margins. Building addition construction will consist of conventional wood frame structures with exterior stucco supported on perimeter and interior continuous strip footings at least 15 inches wide and embedded a minimum of 18 inches into the well-compacted fills reinforced with minimum two #4 bars top and bottom. Spread pad footings will at least 30 inches square and also embedded 18 inches • • I " .,. .,. --- : -• • • Geotechnical Plan Review Update and Response to Review Comments Garst Residential Additions, 3357 Adams Street, Carlsbad, California November 5, 2021 Page3 into approved well-compacted fills. Floor slabs will be a minimum 4.5 inches in thickness, reinforced with #3 reinforcing bars spaced 16 inches on center each way, placed near the slab mid- height. ID. CONCLUSIONS AND RECOMMENDATIONS All conclusions and recommendations provided in the reference report stay valid and should be incorporated into the final plans and implemented during the construction phase. Based on our review of the project plans, an additional study, analyses, and/or amended or revised recommendations are not deemed necessary. IV. GEOTECHNICAL GRADING PLAN REVIEW Based on our review, project most current grading plans substantially propose a similar design concept and are prepared in accordance with the geotechnical recommendations provided in the referenced report. V. FOUNDATION PLAN REVIEW Based on our review of drawings made available to us, and from a geotechnical engineering point of view, with no exception taken, the project foundation plan and details are in substantial compliance with the recommendations provided in the referenced report. The following comments are appropriate: 1. The referenced ''Limited Geotechnical Investigation," report dated June 14, 2021 shall be considered a part of the project foundation plans. 2. In the event a discrepancy(ies) is noted between the foundation plans/details and the minimum requirements of the referenced reports, the most stringent requirement shall govern. VI. RESPONSE TO THIRD PARTY REVIEW The following provide added information, clarifications and our response to the review comments outlined in the "Third-Party Geotechnical Review (First)" by Hetherington Engineering, Inc. dated October 8, 2021. Our responses are provided in the same order as the Third-Party Geotechnical Review (see Appendix): Item #1 : We have received and reviewed the project grading plan, and foundation plan and details referenced herein. Based on our review and from a geotechnical engineering point of view, with no exception taken, the project grading plan, and foundation plan and details are in substantial compliance with the recommendations provided in the referenced report. The project plans are prepared in accordance with the geotechnical recommendations provided in the referenced report and an additional study, analyses, and/or amended or revised recommendations are not deemed necessary . Geotechnical Plan Review Update And Response to Review Comments Garst Residential Additions, 3357 Adams Street, Carlsbad, California November S, 2021 Page4 Item #2: An updated Geotechnical Map utilizing the most current Grading Plan showing the existing topography, proposed structures and final design grades, geologic conditions, approximate remedial grading limits and approximate locations of the exploratory test pits are included with this transmittal as Figure 1. Item #3: Updated Cross-Sections A-A' and B-B' utilizing the current grading plan showing the existing topography, proposed structures and final design grades, approximate geologic contacts, and pertinent geologic conditions are attached to this transmittal as Figures 2 and 3. Item #4: Detailed updated descriptions of proposed site grading, structures and site improvements are provided herein, and remain substantially unchanged from those provided in the referenced report. Item #5: Major grading and earthwork are not planned in connection with the proposed building additions and site improvements, and significant grading and construction impacts on the adjacent private properties and improvements, and public right-of-way is not anticipated VD. LIMITATIONS This geotechnical plan review is not a "Plan Check Review''· and does not relieve the responsibility of the project design consultant(s) and contractor(s) to get completely familiarized with the requirements of the project soil report(s) and fully incorporate its recommendations into the project design, plans and construction works, where appropriate, and as applicable. Our review and comments are for general geotechnical conformance of the project plans with the intent of the project soil reports and design recommendations. Review of structural and civil engineering calculations, architectural intent and structural and civil engineering design modeling and basis, verification of set back requirements, easements and right-of-ways, as well as code, city and county compliance are beyond geotechnical engineering services. It is the owner's or his (her) representative's responsibility to provided copies of all pertinent soil report(s), updates, addendums and plan review letters to respective design consultant(s), and general contractor and his (her) subcontractor(s) for full compliance. I I I • Geotecbnical Plan Review Update And Response to Review Comments Garst Residential Additions, 3357 Adams Street, Carlsbad, California November S, 2021 Pages Should any questions arise concerning this report, please do not hesitate to contact this office. Reference to our Project: GI-21-07-145 will help to expedite our response to your inquiries. This opportunity to be of service again is sincerely appreciated. 61/8Geotechnical Solutions, Inc. S§.,M';;;.,,~ ~ Project Geologist Attachments: Geotechnical Map (Figure 1) Appendix: Geologic Cross-Sections A-A' and B-B' (Figures 2 and 3) "Third,-Party Geotechnical Review (First), by Hetherington Engineering, Inc. dated October 8, 2021 Distribution: Addressee (3, e-mail) 6116 GEOTECHNICAL SOLUTIONS, INC. I I ' GEOTECHNICAL SITE PLAN 33S7 ADAMS STREET, CARLSBAD, CA SCALE: 1 • = 20' o· legend CJ Produced Building Location ~ Geologic Cross Section -Approximate Location of Test Pit Uar Undocumented Fill Qs Topsoil Qop Old Paralie Deposits r_) Approx. Limits of Remedial Gnding Approx. Limits of r_) Remedial Gnding Completed to this Date Under SMS Observations and Testing SMS CEOTECHNICAL SOLUTIONS lNC 5931 Sea Lion Place, Suilc 109 Carbbad, CA 92010 20' \ \ \ \ \ \ I \ ' \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \, ~ I ...... \ 3331 ,s,AMS STREET B' APN:205-112-22 B' : . <t_ EXIST"!G POOi. "-= -=,s ei"oew"-r",~iiEeo1 3375 ADAMS STREET APN:205-112-20 / I ,,I / 3337 ~1,JAS STREET B' APN:205--112-22 Uaf/Qs op l'a.NM-Ul1. I 1s ee o.tAn"',1T.!S'i>Eeoi 3375 ADAMS STREET APN:205-112-20 IMtL 1E_,,KIMT 4~ ... 4 ' I l GEOLOGIC CROSS-SECTION A-A' Legend -----, -----'J.. Geologic I I Existing Building Contact (Approx.) I 3357 ADAMS STREET, CARLSBAD, CA I , ____ _, 8 SCALE: l" = 20' O' 20' D Proposed Building Artificial Fill --Existing Grade ~ Topsoil --. . LJ Test Pit Location , .. ·_Qoi,·. \ Old Paralic Approximated Deposits A A' 140 Proposed Deck 130 120 110 100 --------------------, Existing . . l Proposed 2: I I . r Slrm W.11 .,_,..,, Boildiog , Exi . Fill Slope Proposed Addition l sting Grade &: i----~--·---13· --,-·_;;s~ -----tL-... ------~----~-------1------· ____ -:-:--• .!---. ___ ....:=:1...:..----l--::.--::.::.----l----:::. __ ,_.-"""7~ .. •' ---..-----·--?-----.--.~ . ~ . . . . . . . ~ ,--;::; -: ---"'·-:-· Tl'·' · . . ·. · n'-r . · ·. · . · · · · · · . · : Art•11c•o1· ,m·(U;Q · · · · . · . · .. ·. • _Topsoil (Q~) : . · . · . : . · .. · _·. ~l_d P!ira\ic·~epo~its (~p)_ : ·. · · 90 1. . ",· ·.1 SMS GEOTECHNICAL SOLUTIONS INC 5931 Sea Lion Place, Suite I 09 C.rl1bad, CA 92010 Project Number: Gl-21-05-131 Figure Number: 2 -, - GEOLOGIC CROSS-SECTION B-B' Legend -----, 3357 ADAMS STREET, CARLSBAD, CA j j Existing Building ~ --• .7-• Geologic , ____ _. Contact (Approx.) SCALE: 1" = 20' SMS GEOTECHNICAL SOLUTIONS INC O' 593 I Sea Lion Place, Suite 109 Carlsbad, CA 920 IO 140 130 120 110 100 B 20' Propo: Proposed Deck D Proposed Building I ~ -Uaf I Artificial Fill ... -..... Existing Grade ·>·Qs·: · · ~ .1 ... ~-: : .-_:: ... :. : opso1 LJ Test Pit Location Approximated r-·_Q~i>·. 1 B' Old Paralic Deposits I I I Fill Slope . . Proposed PL Proposed Addition C rt I PL arpo I Existing Grade ,,, _ _ _ _ ___ j _ ' .. ------¥:f--9f:f· . ~-~--'----l ~~--,~--.... · ..... , .... •.• -· ~.-~-i+--=c:.=~~~=~=~=-~ 0 --~-• : :~·. -~-:·~:-• • •• ~-:-' ••••• ·_-:-. ~--.·,: · · · .. ·.·TP-J.. ... · .. · . :. < · ... JP-2 . •1:P:.3 .. · ~fi~ial Fill (J.J~f). . ·,_. :J'opsoil(Qg) . ·.·::. ·o·ld.P:_: 1·':D·. >.t .~Qo· )·:. · ·· .. ;,: ,,.:, ... :·:,-·. · .. : .. . . .. .. . . ara 1c. epos1 s \ p . . ..... • . :-.. , .. . . . . . . . . ~ : -~ . ' . ~ -.. ·• 90--------------------------------.....;.ii Project Number: GI-21--05-131 Figure Number: 3 ~ ~ I I APPENDIX I I I I I I I I I HETHERINGTON ENGINEERING, INC. SOIL & FOUNDATION ENGINEERING • ENGINEERING GEOLOGY• HYDROGEOLOGY City ,,f Carlshati I .and Dc-,·l'l\,pmc-nt Engineering I t,.~S F am\fay Avenue CarlsNhi. California 92008-7314 Anenti,,n: Ms. Elissa Tovar Su~ject: TI-IIRD-PARTY GEOTECHNICAL REVIEW (FIRST) 3357 Adams Street Carlsbad, California GR2021-0030 (DWGS33-2A) October 8, 2021 Project No. 9502.1 Log No. 21633 References: I. ..Limited Geotechnical Investigation"' Proposed New Attached Building Additions, Existing Residence, 3357 Adams Street, Carlsbad, California" by SMS Geotechnical Solutions, Inc., dated June 4, '2021 . ·2. "Grading Plan, Garst Residence, 33S7 Adams St., Carlsbad, CA" by Mike Leeper, P.E., dated September 16, 2021 (Sheets I through 6 of 6). Dear Ms. Tovar: In accordance with your request, Hetherington Engineering, Inc. has provided third-party geotechnical review of Reference I. The following comments are provided for analyses and/or response by the Geotechnical Consultant I. The Consultant should revkw the ;1r:>ject grading plan (Reference 2) and foundation plans, provide any addi1i0nal gcotechnical analyses/recommendations considered necessary, and confinn that the plans have been prepared in accordance with the geotechnical recommendations. 2. The Consultant should provide updated geotechnical mop utilizing the current grading plan for the project to clearly show (at minimum): a) existing site topography, b) proposed structures/improvements, c) proposed finished grades, d) geologic conditions, e) locations of the subsurface exploration, f) temporary construction slopes, g) remedial grading, etc. 5365 Avenida Encinas, Suite A• Carlsbad, CA 92008-4369 • (760) 931-1917 • Fax (760) 931-0545 333 Third Street • Laguna Beach, CA 92651 • (949) 715-5440 • Fax (949) 715-5442 www.hetheringtonenglneering.com ~ I I I I I I ' I THIRD-PARTY Ol:OTEl'IINll'AL REVIEW (FIRST) P~jt>cl N,l. 9502.1 Lc,g No. 2 I ClJJ Octoh<'r R. 2021 Pagr ~ 3. The Consultant should provide geologic cross-sections utilizing the current grading plan to clearly show (at minimum): a) existing topography, b) propos~d structures/improvements, c) proposed finish grades, d) geologic contacts, e) geologic structure. O locations of the subsurface exploration, g) temporary construction slopes, and h) remedial grading, etc. 4. The Consultant should provide an updated description of proposed grading and construction. S. The Consultant should address impacts to adjacent property and improvements as a result of site grading and construction. Please call if there are any questions. Sincerely, HETHERINGTON !~~~~~~~~~ . 11S3 /4~~':,/ ~(f/4:: 'I!// ~f...~ -Paul A._Bogseth -~ -·"1-, · ~~~D-1:fetherington Professional Geo ; . ~ , .• -~:cfv1l Engineer 30488 Certified Engin ring Geologist I J 53 Gcotechnical Engineer 397 Certified Hydrogeologist 591 (expires 3/31/l022) (expires 3/31/2022) Distribution: I-via e-mail (ldetrackingdesk@carlsbadca.gov) I-via e-mail (Emad.Elias@carlsbadca.gov) I-via e-mail (Tim.Carroll@carlsbadca.gov) HETHERINGTON ENGINEERING, INC. I LIMITED GEOTECHNICAL INVESTIGATION PROPOSED NEW ATTACHED BUILDING ADDITIONS EXISTING RESIDENCE 3357 ADAMS STREET CARLSBAD, CALIFORNIA June 14, 2021 Prepared For: Dr. Shane Garst 3357 Adams Street Carlsbad, California 92008 shanegarst@gmail.com Prepared By: §MS Geotechnical Solutions, Inc. 5931 Sea Lion Place, Suite 109 Carlsbad, California 92010 Project No. GI-21-05-131 Project No. GI-21-05-131 June 14, 2021 Dr. Shane Garst 3357 Adams Street Carlsbad, California 92008 SM§ GEOTECHNICAL SOLUTIONS, INC. Consulting Geotechnical Engineers 5931 Sea Lion Place, Suite 109 Carlsbad, California 92010 Office: 760-602-7815 smsgeosol.inc@gmail.com Limited Geotechnical Investigation, Proposed New Attached Building Additions Existing Residence, 3357 Adams Street, Carlsbad, California Pursuant to your request, SM§ Geotechnical Solutions, Inc. has completed the attached Limited Geo technical Investigation for the proposed new attached building additions at the above-referenced residential property. The following report summarizes the results of our research and review of the pertinent documents and reports, subsurface exploratory test pit excavations, field in-situ testing and sampling, laboratory testing, engineering analysis and provides conclusions and recommendations for the proposed new building additions, as understood. From a geotechnical engineering standpoint, it is our opinion that the study areas of the project property are suitable for the support of new attached building additions provided the recommendations presented in this report are incorporated into the design and construction of the project. If you have any questions or need clarification, please do not hesitate to contact this office. Reference to our Project No. GI-21-05-131 will help to expedite our response to your inquiries. R18 C1077 03740 E329 AASH!D A CCREDITED TABLE OF CONTENTS I. INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 II. SITE DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . • . . . . • . • . . . . . . . . . . . . . . . . . . 1 III. PROPOSED DEVELOPMENT .......................................... 2 IV. FIELD INVESTIGATION .............................................. 2 V. REGIONAL GEOLOGIC SETTINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 VI. GEOTECHNICAL CONDITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 A. Earth Materials . . . . . . . . . . . . • . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 B. Groundwater and Surface Drainage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 C. Geologic Hazards and Slope Stability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 D. Site Classification for Seismic Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 E. Seismic Design Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 VII. FAULTS AND SEISMICITY ............................................ 6 VIII. LABORATORY TESTS AND TEST RESULTS .. .. . .. . .. . . . .. . . .. . .. . .. . .. 8 IX. SITE CORROSION ASSESSMENT ...................................... 12 X. CONCLUSIONS ..............••...................................... 13 XI. RECOMMENDATIONS ................................................ 16 A. Remedial Grading and Earthworks .................................... 17 B. Footings and Slab-on-Grade Floor Foundations ......................... 24 C. Soil Design Parameters .............................................. 25 D. Exterior Concrete Slabs / Flatworks ....•.............................. 27 E. General Recommendations ........................................... 28 xn. GEOTECHNICAL ENGINEER OF RECORD (GER) ....................... 30 XIII. LIMITATIONS ....................................................... 30 REFERENCES TABLE OF CONTENTS (continued} FIGURES Regional Index Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Geotechnical Site Plan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Test Boring Logs ..........•..........•......••..............•............. 3 -5 Geologic Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Geologic Cross-Section A-A' . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • . . . . . . 7 Geologic Cross-Section B-B' . . . . . . . . . . . . • . • . . . . . . . . . . • . • . . . . . . • • . . • . . . . . . . . . • . . 8 Regional Fault Map ..................................••....................... 9 Grain Size Analysis .......................................................... 10 Typical Over-Excavation and Recompaction Detail ............................... 11 Typical New Adjacent to Existing Foundation Detail .............•.....•....•..... 12 Typical Retaining Wall Back Drainage ....•.....•........•....................•. 13 Typical Isolation Joints and Re-Entrant Corner Reinforcement ..................... 14 Typical Pipes Through or Trench Adjacent to Foundations ......................... 15 APPENDIX ASCE 7 Hazard Report LIMITED GEOTECHNICAL INVESTIGATION PROPOSED NEW ATTACHED BUILDING ADDITIONS EXISTING RESIDENCE 3357 ADAMS STREET CARLSBAD, CALIFORNIA I. INTRODUCTION The project property consists of an existing developed, rectangularly shaped lot located east of Interstate 5 Freeway and south of Basswood A venue, on the west side of Adams Street within limits of the city of Carlsbad. The property is currently occupied by an existing older residence in the central portions that is currently underremodeling and reconstruction. The approximate site location is shown on a Regional Index Map attached to this report as Figure 1. The approximate site coordinates are 33.1604°N latitude and -l 17.3377°W longitude. We understand that a western pre-existing attached garage was demolished and removed to allow for construction of a new 2-story attached building addition within the same footprint. Additional local building extensions are also planned around the residence perimeter. Consequently, the purpose of this limited study was to evaluate shallow foundation bearing soil conditions at the proposed new building additions, and to ascertain their influence upon the planned new construction. Exploratory test pit excavations, soil sampling, laboratory testing and engineering analysis were among the activities conducted in conjunction with this effort which resulted in the remedial bearing and subgrade soil preparations and foundation recommendations presented herein. The scope of this work was limited to those areas planned for the new building additions as specifically delineated in this report. Other areas of the property, including the existing residence/remodel, site structures and improvements, were not investigated, and are beyond the scope of this limited work. II. SITE DESCRIPTION A Geotechnical Site Plan, reproduced from the project Plot Plan prepared by Indo White Interior Design & Drafting ( dated March 22, 2021 ), depicting existing residence and the proposed new building additions is included herein as Figure 2. In general, the property is a gently sloping parcel that descends westerly at a roughly 10 percent gradient from Adams Street grade to neighboring off site property to the west. Similar residential developments border the property to north and south. Central portions of the property are occupied by a split-level building with raised floor type foundations. Associated improvements include existing perimeter structures, swimming pool and site improvements. A masonry elevation-transition perimeter stem wall type foundation separates the existing upper eastern portions of the residence from the lower western pre-existing garage portion. A retaining wall on the order of 4 feet high, backfilled with imported soils to create extended level surfaces, also marked the western perimeter of the building pad and is now demolished and removed. All site structures, swimming pool and associated improvements are currently under remodeling and reconstruction. We understand that all remnants of old slabs and Limited Geotechnical Investigation Proposed New Attached Building Additions, 3357 Adams Street, Carlsbad June 14, 2021 Page2 foundations in the project areas planned for new attached building additions will also be removed. Engineering and grading records pertinent to the original building pad development and existing constructions are not available. Access to the site is via an unimproved driveway off of Adams Street along the northern property margins. Presently, the property is mostly devoid of landscaping. Existing drainage appears to generally sheetflow over site surfaces westward toward lower elevations. Excessive scouring or erosion was not noted at the time of our field study. III. PROPOSED DEVELOPMENT Based on the project current plans (Figure 2), planned construction will consist of a 2-story attached building addition within the limits of pre-existing garage footprint, a new 2-car covered carport at the end of existing driveway on the northwestern building perimeter, and local building extensions around the perimeter. Major ground modifications or creation oflarge graded slopes is not proposed in connection with the construction of new building addition/extension, with final grades planned at or very near the existing grades. However, minor fine/contour grading efforts and construction of new short transition retaining walls in same lower pad perimeter areas, as well as new stair cases are anticipated to achieve final design grades, redevelop the new level building addition and perimeter improvements finish grades and establish positive drainage away from the building foundations. We understand that the new construction will consist of conventional wood frame structures with exterior stucco supported on conventional shallow continuous strip and spread pad footings and slab- on-grade floor foundations. IV. FIELD INVESTIGATION Subsurface conditions at the project building addition site were chiefly determined by the excavation of three exploratory test pits dug with amini-excavator(KUBOTA KX121 -2). Test pits were logged by our field geologist, who also supervised in-situ testing and the collection of representative soil samples at selected intervals for subsequent laboratory testing. Approximate test pit locations are shown on the enclosed Figure 2. Detail logs of the exploratory test pits are attached to this report, as Figures 3, 4 and 5. Laboratory test results and engineering properties of selected representative soil samples are summarized in following sections. Limited Geotechnical Investigation June 14, 2021 Page3 Proposed New Attached Building Additions, 3357 Adams Street, Carlsbad V. REGIONAL GEOLOGIC SETTINGS The subject property is located in the Coastal Plains subdivision of the Peninsular Ranges geomorphic province of San Diego. The coastal plain area is characterized by Pleistocene marine terrace landforms. These surfaces are relatively flat erosional platforms that were shaped by wave action along the former coastlines. The step-like elevation of the marine terraces was caused by changes in sea level throughout the Pleistocene and by seismic activity along the Rose Canyon Fault Zone located west of the coastline. The Rose Canyon Fault Zone is one of many northwest trending, sub-parallel faults and fault zones that traverse the nearby vicinity. Several of these faults, including the Rose Canyon Fault Zone, are considered active faults. Further discussion of faulting in regards to the site is discussed in the Geologic Hazards section of this report. A Geologic Map showing mapped units at and nearby the study location is attached as Figure 6. VI. GEOTECHNICAL CONDITIONS The project property is mostly a gently sloping partially graded building pad underlain by Old Paralic Deposits. Instability or adverse geotechnical conditions which could preclude the proposed new building addition/extensions are not indicated. Geologic Cross-Sections A-A' and B-B' depicting our interpretation of subsurface conditions based on the exploratory test pit excavations borings are included with this report as Figures 7 and 8. The following earth materials were recognized: A. Earth Materials Old Paralic Deposits (Qop2-4): Quaternary age Old Paralic Deposits, typical of local coastal areas of San Diego County, underlie the project property at relatively shallow depths. As exposed in our exploratory test pits, the underlying Old Paralic Deposits consist of upper highly weathered olive green brown colored silty clay to clayey silt deposits grading to silty sandstone units with depth. The upper highly weathered deposits mostly occur in a damp to very moist and moderately firm to firm condition, while lower exposure were found to occur in a dense to very dense condition. The dense Old Paralic Deposits below the upper highly weathered deposits are considered suitably dense for providing an adequate support for the project new fills, structures and improvements. The upper highly weathered deposits should be regraded as a part of the project remedial grading efforts, as specified in the following sections. Topsoil (Qs): A relatively shallow section of topsoil, on the order of2 feet thick maximum, overlays the underlying Old Paralic Deposits with a gradational contact. Site topsoil layers generally consist of light to dark brown plastic silty clay materials in very moist to wet and soft to moderately firm conditions overall. Onsite topsoil range to highly expansive and can be detrimental to new structures and improvements if they occur near finish pad grade levels. Removals and disposal of these deposits from the planned new building addition sites are recommended in the following sections. Limited Geotechnical Investigation Proposed New Attached Building Additions, 3357 Adams Street, Carlsbad June 14, 2021 Page4 Artificial Fill (Uai): A mantle of artificial fills, mostly consisting of tan to light brown color silty fine to medium grained sand, approximately 3.5 feet thick, overlay the project site topsoil deposits. Site existing artificial fills are chiefly in slightly moist to moist and loose to very loose conditions overall and contain construction and demolition debris. Existing fills also include a section of light grey loose sand to silty sand materials that appear to be imported backfill soils for the pre-existing site retaining walls. Detailed descriptions of the underlying soil profile are presented in the attached Test Pit Logs, Figures 3, 4 and 5. Project artificial fills and upper weathered loose exposures of the underlying Old Paralic Deposits are compressible, not suitable for the support the planned new structures and improvements. These deposits should be regarded as specified in the following sections. Site plastic clayey topsoil layers are recommended for removals and disposal. B. Groundwater and Surface Drainaee Subsurface groundwater seepage was locally encountered in our Test Pit TP-3 excavation at approximately depth of7 .25 feet below the existing ground surface (BGS), at the time of our field explorations. The noted seepage condition generally represents a perched groundwater condition at the base of highly weathered Old Paralic Deposits near the top of more cemented units. The noted groundwater is mostly developed from upslope irrigation and meteoric waters. Seepage quantities were minor but may be expected to fluctuate based on seasonal and annual rainfall conditions. The noted local seepage condition is sufficiently deep below the recommended remedial grading depths, as specified herein, and is not expected to create a major construction difficulty, or significantly impact the future performance of planned new additions. However, some local dewatering, bottom of removals/over-excavations stabilization with crushed rocks or installation of subsurface drainage system may become necessary based on actual field exposures and should be anticipated. Like all graded building sites, the proper control of site surface drainage and efficient irrigation techniques are critical components to overall stability of the project graded surfaces, as well as continued performance of the existing and new building addition/extensions. Surface water should not pond upon graded surfaces, and irrigation water should not be excessive. Perimeter surfaces should direct runoff away from the building foundations and site improvements in a positive manner. Surface runoff should be properly captured and discharged into approved drainage facilities. All site retaining and building stern walls should be provided with a well-constructed back drainage system. All underfloors shall be provided with an adequate cross ventilation per applicable codes and standards. Limited Geotechnical Investigation Proposed New Attached Building Additions, 3357 Adams Street, Carlsbad C. Geologic Hazards and Slope Stability June 14, 2021 Pages Geologic hazards are not presently indicated at the project site. Significant slopes are not present at or in close proximity to the project property, nor are any are planned in conjunction with the proposed new constructions. The most significant geologic hazards at the property will be those associated with ground shaking in the event of a major seismic event. Liquefaction or related ground rupture failures are not anticipated. D. Site Classification for Seismic Design Site soils are classified based on the upper 100 feet maximum of a site subsoil profile. In the absence of sufficient or specific site data, appropriate soil properties are permitted to be estimated by the project geotechnical consultant based on known geotecbnical conditions, and Site Class Dis typically used as a "default," unless otherwise noted. Site Classes A and B shall not be assigned to a site, if there is more than 10 feet of soil ( or fill) between the top of the underlying rock surface and bottom of the foundation. Site Classes A and Bare most commonly supported by shear wave velocity determination (us, ft/s). Site Class F, which may require a site response analysis, consists ofliquefiable or collapsible soils and highly sensitive clayey soil profiles. Site Classes C, D, and E soils may be classified using an average field Standard Penetration Resistance (N) method for soil layers based on Section 20.4.2 of ASCE 7-16. Where refusal is met for a rock layer (blow counts of 50 or greater for 6 inches or less penetration), Ni is taken as 100 blows per foot. Site Classification is then established based on Table 20.3-1 of ASCE 7-16. Requirements provided below are also applicable and should be incorporated in the project designs where appropriate: 1. Site specific hazard analysis is required (see Section 11.4.8) in accordance with Chapter 21.2 of ASCE 7-16 for structures on Site Class E sites with values of Ss greater than or equal to l .0g, and structures on Site Class D and E sites with values of S 1 greater than or equal to 0.2g. However, the following 3 exceptions are permitted for Equivalent Lateral Force design (ELF) using conservative values of seismic design parameters in lieu of performing a site specific ground motion analysis: * Structures on Site Class E sites with Ss greater than or equal to 1.0, provided the site coefficient Fa is taken as equal to that of Site Class C. Limited Geotechnical Investigation Proposed New Attached Building Additions, 3357 Adams Street, Carlsbad June 14, 2021 Page6 * For structures on Site Class D sites with S 1 greater than or equal to 0.2, a long period coefficient (Fv) of 1. 7 may be utilized for calculation of Ts, provided that the value of Seismic Response Coefficient (Cs) is determined by Equation (12.8-2) for values of the fundamental period of the building (T) less than or equal to l .5Ts, and taken as 1.5 times the value computed in accordance with either Equation 12.8-3 for T greater than 1.5 Ts and less than or equal to TL or Equation 12.8-4 for T greater than TL. * Structures on Site Class E sites with S 1 greater than or equal to 0.2, provided that T is less than or equal to Ts and the equivalent static force procedure is used for the design. 2. Where Site Class B is recommended, and a site specific measurement is not provided, the site coefficients Fa, Fv, and FPGA shall be taken as unity (1.0) in accordance to Section 11.4.3 of ASCE 7-16. 3. Where Site Class D is selected as the "default" site class per Section 11.4.3 of ASCE 7- 16, the value of Fa shall not be less than 1.2. Where the simplified procedure of Section 12.4 is used, the value of Fa shall be determined in accordance with Section 12.14.8.1, and the values of Fv, SMS and SM! need not to be determined. At the project property, dense to very dense Old Paralic Deposits occur at relatively shallow depths, and based on our past experience with similar deposits, Site Class D (Stiff Soil), can conservatively be considered and used for the project site subsoil profile, unless otherwise noted. E. Seismic Desi2n Values Seismic design values are presented in the attached ASCE 7 Hazard Report, enclosed herein as an Appendix prepared in accordance with Chapter 16, Section 1613 of the 2019 California Building Code (CBC) and ASCE 7-16 Standard. Presented values are generated using ASCE developed web interface that uses the United States Geological Survey (USGS) web services and retrieves the seismic design data in a report format. VII. FAULTS AND SEISMICITY Faults or significant shear zones are not indicated on the project site. As with most areas in California, the San Diego region lies within a seismically active zone; however, coastal areas of the county are characterized by low levels of seismic activity relative to inland areas to the east. During a40-yearperiod (1934-1974), 37 earthquakes were recorded in San Diego coastal areas by the California Institute ofTechnology. None of the recorded events exceeded Limited Geotechnical Investigation Proposed New Attached Building Additions, 3357 Adams Street, Carlsbad June 14, 2021 Page7 a Richter magnitude of 3. 7, nor did any of the earthquakes generate more than modest ground shaking, and did not produce significant damages. Most of the recorded events occurred along various offshore faults which characteristically generate modest earthquakes. Historically, the most significant earthquake events which affected local areas originated along well known, distant fault zones to the east and the Coronado Bank Fault to the west. Based upon available seismic data, compiled from California Earthquake Catalogs, the most significant historical event in the area of the study site occurred in 1800 at an estimated distance of 11.3 miles from the project area. This event, which is thought to have occurred along an offshore fault, reached an estimated magnitudeof6.5 with an estimated bedrock acceleration valueof0. l 44g at the project site. The following list represents the most significant faults that commonly impact the region. Estimated ground acceleration data compiled from Digitized California Faults (Computer Program EQFAULT VERSION 3.00 updated) typically associated with each fault is also tabulated. TABLE 1 MAXIMUM FAULT ZONE DISTANCE FROM SITE PROBABLE ACCELERATION (R.H.) Rose Canyon Fault 5.2 miles 0.241g Newport-Inglewood Fault 5.3 miles 0.238g Coronado Bank Fault 21.4 miles 0.183g Elsinore-Julian Fault 24.0 miles 0.143g The locations of significant faults and earthquake events relative to the study site are depicted on a Regional Fault Map attached to this report as Figure 9. Recently, the number of seismic events that affect the region appears to have somewhat heightened. Nearly 40 earthquakes of magnitude 3.5 or higher have been recorded in coastal regions between January 1984 and August 1986. Most of the earthquakes are thought to have been generated along offshore faults. For the most part, the recorded events remain as moderate shocks which typically resulted in low levels of ground shaking to local areas. A notable exception to this pattern was recorded on July 13, 1986. An earthquake of magnitude 5.3 shook county coastal areas with moderate to locally heavy ground shaking. This resulted in $700,000 in damages, one death, and injuries to 30 people. The quake occurred along an offshore fault located nearly 30 miles southwest of Oceanside. Limited Geotechnical Investigation Proposed New Attached Building Additions, 3357 Adams Street, Carlsbad June 14, 2021 Page8 A series of notable events shook county areas with a (maximum) magnitude 7.4 shock in the early morning of June 28, 1992. These quakes originated along related segments of the San Andreas Fault, approximately 90 miles to the north. Locally high levels of ground shaking over an extended period of time resulted; however, significant damages to local structures were not reported. The increase in earthquake frequency in the region remains a subject of speculation among geologists; however, based upon empirical information and the recorded seismic history of county areas, the 1986 and 1992 events are thought to represent the highest levels of ground shaking that can be expected at the study site as a result of seismic activity. In recent years, the Rose Canyon Fault has received added attention from geologists. The fault is a significant structural feature in metropolitan San Diego that includes a series of parallel breaks trending southward from La Jolla Cove through San Diego Bay toward the Mexican border. Test trenching along the fault in Rose Canyon indicated that at that location the fault was last active 6,000 to 9,000 years ago. More recent work suggests that segments of the fault are younger having been last active 1,000-2,000 years ago. Consequently, the fault has been classified as active and included within an Alquist-Priolo Special Studies Zone established by the State of California. Furthermore, a more recent study concluded that the coastal region of San Diego may experience earthquakes up to magnitudes 7.3 and 7.4 (Sahakian et al, 2017). This study used the Newport-Inglewood/Rose Canyon Fault offshore. An earthquake of this magnitude has likely not occurred in the last 100,000 years, according to the data. Fault zones tabulated in the preceding table are considered most likely to impact the region of the study site during the lifetime of the project. The faults are periodically active and capable of generating moderate to locally high levels of ground shaking at the site. Ground separation as a result of seismic activity is not expected at the property. VIII. LABORATORY TESTS AND TEST RESULTS Earth deposits encountered in our exploratory test borings were closely examined and sampled for laboratory testing. Based upon our test pits, and field exposures site soils have been grouped into the following soil types: TABLE2 I Soil Tl'.J!e I Descril!tion I I Tan to light green brown silty sand (Artificial Fill) 2 Light grey to dark brown silty clay (Topsoil) 3 Olive-green brown silty clay to clayey silt (Highly Weathered Old Paralic Deposits) 4 Olive-green silty sandstone (Old Paralic Deposits) 5 Light grey sand to silty sand (Artificial Fill) Limited Geotechnical Investigation June 14, 2021 Page9 Proposed New Attached Building Additions, 3357 Adams Street, Carlsbad I I I I The following tests were conducted in support of this investigation: A. Grain Size Analysis: Grain size analyses were performed on representative samples of onsite Soil Types 1 and 4. The test results are presented in Table 3 below, and graphically illustrated on the attached Figure 10. TABLE3 Sieve Size II ½" I #4 I #10 I #20 I #40 I #100 I #200 I Location I Soil Type II Percent Passing I TP-1 @2' l 100 100 99 81 36 27 TP-1 (@ 5' 4 100 99 98 94 74 35 27 B. Liquid Limit, Plastic Limit and Plasticity Index: Liquid limit, plastic limit and plasticity index tests were performed on representative samples of Soil Type 3 m accordance with the ASTM D4318. Test results are tabulated in table 4. TABLE4 Location Soil Type Liquid Limit Plastic Limit Plasticity Index lLL-%) (PL-%) {PI=LL-PL) TP-1 @4' I 3 I 28 I 21 I 7 I C. Maximum Dry Density and Optimum Moisture Content: The maximum dry density and optimum moisture content of Soil Types 1 and 3 were determined in accordance with ASTM D1557. The test results are presented in Table 5 below. TABLES Location Soil Maximum Dry Optimum Moisture Type Density (Tm-pcO Content (c.>opt-%) TP-1 @2' I 1 I 126.0 I 9.5 I TP-1 @H' 3 116.0 15.8 D. Unit Weight & Moisture Content Tests: In-place dry density and moisture content of collected representative soil samples were determined from relatively undisturbed chunk samples using the Water Displacement method (Method A) in accordance with ASTM D7263, and Water Content of Soil and Rock by Mass test method in accordance with ASTM D2216. The test results are presented in Table 6 and tabulated on the attached Test Pit logs at corresponding locations. Limited Geotechnical Investigation Proposed New Attached Building Additions, 3357 Adams Street, Carlsbad TABLE6 Field Field Dry Max.Dry To-Place Sample Soil Moisture Density Density Relative Location Type Gontent (rd-pct) (rm-pcf) Compaction (Ca>-%) TP-1 @2' 1 6 -126.0 Sample Disturbed TP-1 @3' 2 19 107.6 -- TP-1 @4' 3 11 123.5 116.0 100+ TP-1 @5' 4 11 119.6 -- TP-2@3.5' 2 21 98.9 -- TP-2@4.5' 2 17 107.2 -- TP-2 @6.5' 4 17 115.1 -- TP-3 @3' 2 20 105.9 -- TP-3 @4.5' 3 18 103.9 116.0 90 TP-3@ 5.5' 3 23 104.7 116.0 90 Assumptions and Relationships: In-place Relative Compaction = (id+ Ym) Xl00 GS(ST-1) = 2.65, GS(ST-2) = 2.75 e = (Gs Yw + Yd) -1 S = (w Gs)+ e June 14, 2021 Page 10 Degree of Saturation S(¾) - 95 78 70 81 81 96 94 77 100 E. Expansion Index Test: One expansion index (EI) test was performed on a representative sample of onsite Soil Type 3 in accordance with the ASTM D4829. The test results, are presented in Table 7. Limited Geotechnical Investigation Proposed New Attached Building Additions, 3357 Adams Street, Carlsbad TABLE7 Sample Soil Molded Degree of Fin.al Initial Dry Measured (,) Saturation 6) Density Location Type (%) (%) (%) (PCF) EI I TP-1 @ 4' I 3 I 13.4 I 52 I 24.8 I 99.4 I 35 u> = moisture content in percent. Elso = Eimeas -(50 -Smeas) ((65 + Elmeas) + (220 -Smeas)) Expansion Index (EI) Expansion Potential 0-20 Very Low 21 -50 Low 51 -90 Medium 91 -130 High ) 130 Very High June 14, 2021 Page 11 El 50% Saturation I 37 I F. Direct Shear Test: One direct shear test was performed on a representative remolded sample of onsite Soil Type 1 in accordance with ASTM D3080. The prepared specimen was soaked overnight, loaded with normal loads of 1, 2, and 3 kips per square foot respectively, and sheared to failure in an undrained condition. The test results are presented in Table 8 below. TABLES Sample Soil Sample Unit Angle of Apparent Weight Tot. Frie. Cohesion Location Type Condition (rw-pcf) (~-Deg.) (c-psf) TP-1 /a22' 1 Remolded to 90% ofY m /a2 % u>opt 123.6 32 100 G. pH and Resistivity Test: pH and resistivity of a representative sample of onsite soil was determined using "Method for Estimating the Service Life of Steel Culverts," in accordance with the California Test Method (CTM) 643. The test result is tabulated in Table 9. TABLE9 Sample.Location Soil Type Minimum Resistivity (OHM-CM) pH TP-1 @3' 2 530 7.3 H. Sulfate Test: A sulfate test was performed on a representative sample of onsite soils in accordance with the California Test Method (CTM) 417. The test result is presented in Table 10. Limited Geotechnical Investigation June 14, 2021 Page 12 Proposed New Attached Building Additions, 3357 Adams Street, Carlsbad I I IX. TABLE IO Sample Location Soil Type Amount of Water Soluble Sulfate In Soil(% by Weight) TP-1 @3' I 2 I 0.014 I H. Chloride Test: A chloride test was performed on a representative sample of onsite soils in accordance with the California Test Method (CTM) 422. The test result is presented in Table 11. TABLE 11 Sample Location Soil Type Amount of Water Soluble Chloride In Soil(% by Weight) TP-1@3' I 2 I 0.019 I SITE CORROSION ASSESSMENT A site is considered to be corrosive to foundation elements, walls and drainage structures if one or more of the following conditions exist: * Sulfate concentration is greater than or equal to 2000 ppm (0.2% by weight). * Chloride concentration is greater than or equal to 500 ppm (0.05 % by weight). * pH is less than 5.5. For structural elements, the minimum resistivity of soil ( or water) indicates the relative quantity of soluble salts present in the soil ( or water). In general, a minimum resistivity value for soil ( or water) less than 1000 ohm-cm indicates a potential for presence of high quantities of soluble salts and a higher propensity for corrosion. Appropriate corrosion mitigation measures for corrosive conditions should be selected depending on the service environment, amount of aggressive ion salts ( chloride or sulfate), pH levels and the desired service life of the structure. Results oflimited laboratory tests performed on selected representative of site soil samples indicated that the minimum resistivity is less than 1000 ohm-cm suggesting a potential for presence of high quantities of soluble salts. However, test results further indicated that pH levels are greater than 5.5, sulfate concentrations are less than 2000 ppm and chloride concentration levels are less than 500 ppm. Based on the results of the available limited corrosion analyses, the project site may be considered non-corrosive. Limited Geotechnical Investigation Proposed New Attached Building Additions, 3357 Adams Street, Carlsbad June 14, 2021 Page 13 §MS Geotechnical Solutions, Inc. does not consult in the field of corrosion engineering and the client, project architect or structural engineer should agree on the required level of corrosion protection, or consult a corrosion engineer as warranted. However, based on the result of the tested soil sample, the amount of water soluble sulfate (SO4) was found to be 0.014 percent by weight (140 ppm) which is considered negligible according to ACI 318 (SO Exposure Class with Not Applicable severity). Water soluble chloride (CL) was found 0.019 percent by weight (190 ppm), and site is not located within 1000 feet of salt or brackish water (anticipated concrete dry or protected from moisture). Consequently, exposures to chloride may also be considered negligible (CO Exposure Class with Not Applicable severity). In our opinion and as a minimum, concrete consisting of Portland cement Type II (ASTM C150) with minimum 28 days compressive strength (f'c) of2500 psi and maximum 0.50 water-cement ratio is considered typically adequate for SO and CO Class exposures, unless otherwise specified, or noted on the project plans. Table 12 below is appropriate based on the pH-Resistivity test results. Adequate protective measures against corrosion should be considered for all buried metal pipes, connections, elbows, conduits, concrete reinforcements and inserts, improvements and structures, as necessary and appropriate. Buried metal pipes and conduits should be wrapped and provided with appropriate protective cover where applicable. TABLE 12 Design Soil Type Gauge 16 14 12 10 11 2 Years to Perforation of Metal Culverts 29 38 53 68 83 X. CONCLUSIONS Based on the foregoing investigation, the planned new building additions/extensions and site improvements at the project property, substantially as proposed, are feasible from a geotechnical viewpoint. The project building addition areas of the property are generally underlain by a section artificial fills and topsoil over highly weathered Old Paralic Deposits. Below the highly weathered silty to clayey zone, dense sandstone deposits occur. Adverse soil or geologic instabilities that could preclude the planned new building additions were not indicated at the project property at the time of our study. The following factors are unique to the studied areas if the property and will most impact project construction procedures from a geotechnical viewpoint: Limited Geotecbnical Investigation Proposed New Attached Building Additions, 3357 Adams Street, Carlsbad June 14, 2021 Page 14 A. Landslides, faults or significant shear zones are not present at the project site and are not considered a geotechnical factor in the planned site development. The study site is not located near or within the Alquist -Priolo earthquake fault zone established by the State of California. The most significant long-term geologic hazard likely to impact the property is periodic ground shaking associated with earthquake activity along nearby or distant active faults. The project shall be designed and constructed in accordance with the seismic design requirements of the 2019 California Building Code (CBC) and ASCE 7-16 Standard. B. The planned building additions/extensions areas are underlain by a relatively shallow section ofloose to very loose artificial fills and soft plastic clayey topsoils ranging to 5.5 feet thick maximum. Below, Old Paralic Deposits occur in highly weathered conditions grading more dense and tight sandstone with depth. The upper loose surficial soils and underlying highly weathered Old Paralic Deposits are highly compressible deposits not suitable for structural support. These deposits should be over-excavated (removed) to the underlying suitably dense deposits, as approved in the field, and placed back as properly compacted fills in accordance with the recommendations of this report. Minimum over-excavation (removal) depths are provided in the following sections. C. Site topsoil layer is on the order of 2 feet thick and consists of plastic potentially high expansive clayey materials. Plastic clayey soils typically require added remedial grading efforts to process and achieve the minimum specified compaction levels, and will be detrimental to site new structures and improvements, where they occur within upper pad grades. Consequently, removals and disposal of these deposits from the planned new building addition areas are recommended herein. Good quality sandy granular import soils can then be used to achieve final design grades. D. Large natural or graded slopes are not present on or near the immediate vicinity of the project, nor are any new slopes are planned in connection with the proposed new constructions. Consequently, slope stability is not considered a major geotechnical concern in the project new constructions. E. Significant grade alterations are also not planned with final building addition/extension pad surfaces proposed at or very near the existing grades. The majority of the project required earth operations are expected to consist of remedial grading work for foundation bearing and subgrade soil preparation. Minor fine or contour grading efforts, however, will also be necessary to develop final building addition and improvement surfaces and establish design drainage patterns. All site excavations, earthwork, remedial and fine grading efforts should be completed in accordance with requirements of the following sections. Limited Geotechnical Investigation Proposed New Attached Building Additions, 3357 Adams Street, Carlsbad June 14, 2021 Page 15 F. Over-excavations and recompaction remedial grading work will be required under all proposed new structures and site improvements in order to construct uniform bearing and subgrade soil conditions throughout, as specified in the following sections. There should be at least 24 inches of well-compacted fills below bottom of the deepest footing(s), and site improvements, unless otherwise approved. G. Added care will be required to avoid any damages to the existing building foundations and nearby on and offsite structures and improvements due to site excavations, remedial earthwork grading and construction work. Adjacent public and private properties and right- of-ways should also be properly marked and protected, as necessary and appropriate. For this purpose, adequate excavation setbacks should be observed and laid back temporary excavation slopes developed where appropriate. Potentially completing excavations and remedial grading works in a limited section(s) and/or providing hydraulic jacks supports for the exposed existing adjacent building foundations may also become required and should be anticipated. H. Earth deposits generated from the excavations of onsite existing fills will predominantly consist of sandy soils, while highly weathered Old Paralic Deposits are expected to generate silty to clayey soils. Generated silty to clayey soils range to low expansion potential and should be buried in deeper fills, and sandy material placed within the upper pad grades using select grading techniques. Import soils should also consist of good quality sandy granular soils placed within surface grades and used for wall and trench backfills. Import soils should meet or exceed the minimum requirements specified in this report. I. Existing site fills contain roots and construction/trash debris. Roots and construction/trash debris should be properly removed, separated and disposed of from the site. Project new fills and backfills should be clean deposits free of trash, roots, stamps, construction and trash debris, organic matter and deleterious materials, properly processed, throughly mixed, placed in thin lifts horizontal lifts and compacted as specified in the following sections. J. Based on our select grading recommendations, as specified herein, and placing good quality sandy granular import soils within the upper pad grades, final bearing and subgrade soil are anticipated to consist of silty sand (SM/SW) materials ranging to very low expansion potential (expansion index less than 20 based on ASTM D4829 classification). Potentially expensive soils will not be a factor in the construction of planned new building additions, provided our recommendations are followed. Limited Geotechnical Investigation Proposed New Attached Building Additions, 3357 Adams Street, Carlsbad June 14, 2021 Page 16 K. Local groundwater seepage was encountered in our test pit excavations at approximately depth of 7.25 feet (BGS). The noted seepage appears to represent a perched groundwater condition within the underlying Old Paralic Deposits atop more cemented units. The noted local seepage, as currently encountered, is sufficiently deep and is not expected to create a major construction difficulty. However, some seepage can be developed in project removals/over-excavations at the time of remedial grading operations requiring local dewatering efforts, stabilization using crushed rock, or the installation of subsurface drainage system as directed in the field. As with all graded sites, the proper control of surface drainage and storm water is a critical component to overall site and building performance. Runoff water should not pond upon graded surfaces, and irrigation water should not be excessive. Over-watering of site vegetation may also create perched water and the creation of excessively moist areas at finished surfaces and should be avoided. Storm water and drainage control facilities should be installed for proper control and disposal of surface water as shown on the approved grading or drainage improvement plans. L. Settlement of foundation bearing soils is not expected to be a major geotechnical factor in the construction of planned new building additions/extensions, provided our recommendations are followed. Post construction foundation bearing soil settlements are expected to be less than approximately I-inch and should occur below the heaviest loaded footing(s). The magnitude of post construction differential settlements, as expressed in terms of angular distortion, is not anticipated to exceed ½-inch in a distance between similarly loaded adjacent structural elements, or a maximum distance of 20 feet. M. Minor cracking and separations may be anticipated between the new building additions/extensions and existing building. Improvements to such normal features for this type of construction can be made by structurally tying the footing/slabs of the new building addition/extension to the existing building foundation where they adjoin, as recommended in the following sections L. Soil collapse, liquefaction and seismically induced settlements will not be a factor in the planned new construction provided our remedial grading and foundation recommendations are followed. XI. RECOMMENDATIONS The following recommendations are consistent with the indicated geotechnical conditions at the project new building additions/extensions and should be reflected in the final plans and implemented during the construction phase. Added or modified recommendations may also be appropriate and should be provided at the final plan review phase: Limited Geotecbnical Investigation Proposed New Attached Building Additions, 3357 Adams Street, Cal"lsbad A. Remedial Grading and Earthworks June 14, 2021 Page 17 Relatively modest remedial and minor fine grading efforts are anticipated in order to construct safe and stable level building additions/extensions surfaces and achieve final design grades. All excavations, grading, earthwork, fill soil materials and processing, placement and compaction procedures should be completed in accordance with Chapter 18 (Soils and Foundations) and Appendix "J" (Grading) ofthe2019 California Building Code (CBC), the Standard Specifications for Public Works Construction, City of Carlsbad Ordinances, the requirements of the governing agencies and following sections, wherever appropriate and as applicable: I. Existing Underground Utilities and Buried Structures: All existing underground waterlines, sewer lines, pipes, conduits, storm drains, utilities, tanks, structures and improvements at or nearby the project site should be thoroughly potholed, identified and marked prior to the initiation of the actual excavations, grading and earthwork. Specific geotechnical engineering recommendations may be required based on the actual field locations and invert elevations, backfill conditions and proposed grades in the event of a grading conflict. Utility lines may need to be temporarily redirected, if necessary, prior to earthwork operations and reinstalled upon completion of earthwork operations. Alternatively, permanent relocations may be appropriate as shown on the approved plans. Abandoned irrigation lines, pipes and conduits should be properly removed, capped or sealed off to prevent any potential for future water infiltrations into the foundation bearing and subgrade soils. Voids created by the removals of the abandoned underground pipes, utilities, facilities, tanks and structures should be properly backfilled with compacted fills in accordance with the requirements of this report. 2. Clearing and Grubbing: Demolish and remove the existing concrete patio slab, and all other existing surface and subsurface structures, tanks, vaults, pipes, old foundations and slabs, improvements, vegetation, tree roots and stumps, and any other unsuitable materials and deleterious matter from all areas proposed for new fills, structures, foundation, and site improvements plus a minimum of 3 horizontal feet outside the perimeter, where possible and as approved in the field. Project demolition efforts should effectively remove all existing old slabs/foundations and remnants of old buried utilities and structures, unless otherwise specifically approved. All debris generated from the site demolition works, clearing, grubbing, debris and vegetation removals should also be properly disposed of from the site. Trash, vegetation and debris generated from the site demolition works should not be allowed to occur or contaminate new site fills and backfills. Limited Geotechnical Investigation Proposed New Attached Building Additions, 3357 Adams Street, Carlsbad June 14, 2021 Page 18 The prepared ground should be observed and approved by the project geotechnical consultant or his designated field representative prior to grading and earthwork. 3. Over-Excavations and Removals: Uniform and stable bearing soil conditions should be constructed under the planned new building additions/extensions and site improvements. For this purpose, over-excavation (removal) and recompaction of site upper loose and compressible surficial soils to the minimum specified depths shall be required in all areas planned to receive new fills, structures, and improvements. Over- excavation and remedial grading should extend a minimum of 5 horizontal feet outside the perimeter building additions/extensions envelop and site improvements, where possible and as directed in the field. Conceptual remedial grading recommendations are schematically illustrated on the attached Typical Over-Excavation And Recompaction Detail, Figure 11 and Typical Remedial Grading Adjacent to Existing Foundations, Figure 12. As shown, over- excavation depths should extend a minimum of 5 feet below rough finish pad grades (RFG), or at least 2 feet below the bottom of deepest footing(s), whichever is more. Minimum 2-foot over-excavations and recompaction below bottom of the footing also applies to the site retaining walls and staircases, where they occur. Locally, deeper removals may be necessary and should be anticipated. The dark brown plastic clay topsoil layer, removed as part of the project over-excavations, should be excluded from the site new fills and backfills, as specified herein. New fills and backfills can only be placed upon firm and non-yielding bottom of over- excavations (in-place densities greater than 85% per ASTM D 1557), as approved in the filed. At the project site, bottom of over-excavations may be expected to expose very moist silty to clayey soils and locally yielding conditions. Consequently, in order to establish a uniform and suitable bottom of over-excavation acceptable for receiving new fills and backfills, a layer of earth reinforcement geogrid (TerraGrid RXl 200 or greater) may become required. The geogrid, ifrequired, should be neatly placed (no wrinkles or kinks) over the prepared bottom exposures, as directed in the field. Installing the earth reinforcement geogrid at the bottom ofremovals will also facilitate achieving minimum specified compaction levels within the site new fills and backfills. Exploratory test pits excavated in connection with our study at the indicated locations (see Figure 2) were backfilled with loose and uncompacted deposits. The loose/uncompacted exploratory trench backfill soils shall also be re-excavated and placed back as properly compacted fills in accordance with the requirements of this report. Bottom of all removals should also be adequately prepared, ripped and recompacted to a minimum depth of 6 inches. The exposed bottom of stripping/removals and over- excavations shall be observed and approved by the project geotechnical consultant or his designated field representative prior to fill or backfill placement. Limited Geotechnical Investigation Proposed New Attached Building Additions, 3357 Adams Street, Carlsbad June 14, 2021 Page 19 4. Trenching and Temporary Construction Slopes: Temporary open excavations and trenching necessary for the project new constructions are expected to be on the order of 5 feet deep maximum. Excavations and removals adjacent to the existing property lines, foundations, improvements and structures should be performed under observations of the project geotechnical engineer. Undermining and damages to the existing adjacent foundations, structures and site improvements, neighboring properties, existing public right-of-ways and easements, and underground utilities to remain shall not be allowed by the project excavations and earthwork operations. Temporary excavations adjacent to the existing building foundations developed for the new building additions/extensions should be constructed at 1: 1 maximum gradients, unless otherwise noted or approved, with the remaining wedge properly keyed-in and benched out as the backfilling progresses, as schematically shown on the Typical Remedial Grading Adjacent to Existing Foundations, Figure 12. The temporary slope development adjacent to the existing building foundations will require geotechnical observations during the excavation operations. Additional recommendations including revised/flatter slope gradients, completing excavations and backfilling in limited sections (one-halflengths) and support of the exposed footings (with minimum 4 ton capacity hydraulic jacks installed underneath the existing footings at 4 feet center to center maximum with 12-inch by 12-inch by 2-inch thick steel plates at the top and bottom, all completely encased in concrete as a part of new footing) should be given at that time as necessary, and should be anticipated. Elsewhere at the project site, temporary excavations and trenching up to 5 feet high maximum should also be developed at 1: 1 maximum laid back slopes. The laid back slope should then be properly benched out and new fills/backfills tightly keyed-in as the backfilling progresses. More specific recommendations should be given in the field by the project geotechnical consultant based on actual site exposures. The project contractor shall also obtain appropriate permits, as needed, and conform to Cal-OSHA and local governing agencies' requirements for trenching/open excavations and safety of the workmen during construction. 5. Fill/Backfill Materials, Shrinkage and Import Soils: Over-excavations and removals of site upper fills will mostly generate silty sand deposits while the lower topsoil layer will produce high plastic clayey materials. Clayey soils generated from the excavation of site topsoil layers should be selectively removed, separated and completely excluded from the site new fills by properly disposing of them. Onsite generated sandy soils will include construction and trash debris, however, they may be considered for reuse as site Limited Geotechnical Investigation Proposed New Attached Building Additions, 3357 Adams Street, Carlsbad June 14, 2021 Page 20 new fills and backfills provided they are adequately cleaned, prepared and properly processed to the satisfaction of the project geotechnical consultant. Soils generated from the highly weathered Old Paralic Deposits will include silty to clayey soils that should be buried in deeper fills, below 3 feet from rough finish pad grades, using select grading techniques. Locally some very moist to wet soils may also be encountered in deeper excavations requiring added spreading, aerating and processing efforts. Placing the well manufactured and moisture conditioned fills in thin lifts with adequate compactive effort using heavy construction equipment suitable to the site soil properties should be considered for achieving the specified compaction levels. Removal and disposal of site highly the plastic and expansive clay topsoil layer, as specified herein, will result in an import balance. Site sandy soils are also expected to shrink approximately 10% to 15% on volume bases when construction debris is removed and clean materials are compacted as specified herein. Consequently, import soils are expected to complete grading and achieve final design grades. Import soils should be good quality sandy granular D.G. type (SM/SW) non-corrosive deposits with very low expansion potential (100% passing I-inch sieve, more than 50% passing #4 sieve and less than 18% passing #200 sieve with expansion index less than 20). Import source/borrow site(s) shall be a "clean" natural site (i.e., no contamination & no toxic/hazards substance) or manufactured (D.G. or Class 2 base) import materials from a sand/materials plant. Source/borrow sites with land use activities where there could be potential contaminants and toxic substance health risks such as industrial and agricultural sites, fuel storage and gas stations, dry cleaners, photographic processing facilities, paint stores, auto repairs/painting facilities, manufacturing and metal processing shops, waist treatment, aerospace facilities, etc. as well as those sites currently undergoing remediation, corrective action, closure activities overseen by the California Department of Toxic Substance Control (DTSC) or other regulatory agencies shall not be allowed. Import fills obtained from construction projects and from demolition debris, asphalt, broken concrete, shall also not be allowed. Import soils should be inspected, tested as necessary, and approved by the project geotechnical engineer prior to delivery to the site. Import soils should also meet or exceed engineering characteristic and soil design parameters as specified in the following sections. Import sandy granular soils should be placed within the upper (minimum 3 feet) of rough finish pad grades. 6. Fill/Backfill Soil Spreading and Compaction: Uniform bearing soil conditions should be constructed at the project new building additions/extensions by the remedial grading and earthworks operations. There should be at least 24 inches of well-compacted fills under the bottom of deepest footing (including site retaining walls), and site improvements rough finish grade elevations (including staircases). Limited Geotechnical Investigation Proposed New Attached Building Additions, 3357 Adams Street, Carlsbad June 14, 2021 Page 21 Project new fills and backfills shall be clean deposits free of trash, debris, roots, stumps, organic matter and deleterious materials. Site new fills and backfills shall be adequately processed, thoroughly mixed, moisture conditioned to approximately 2% to 3% ( or as directed in the field) above the optimum moisture levels depending on the finial mixture, placed in thin (8 inches maximum) uniform horizontal lifts and mechanically compacted with heavy construction equipments to a minimum of 90% of the corresponding laboratory maximum dry density per ASTM D 1557, unless otherwise specified. Added processing and compactive efforts should be anticipated for the moisture sensitive clayey to silty soils generated from the highly weathered Very Old Paralic Deposits. 7. Groundwater Seepage and Dewatering: Local subsurface perched groundwater seepage was encountered in our one of our test pit excavation (TP-3) at approximately depth of 7.25 feet (BOS). The noted local seepage condition occurs below the bottom of the recommended over-excavation depths, as specified herein, and is not expected to create a major construction difficulty. However, some seepage can develop in project deeper removals/over-excavations and should be anticipated. Intruding groundwater seepage, if any encountered, should be properly removed using appropriate dewatering method(s) suitable to site conditions, in order to create neat and stable work area, and allow construction to proceed. Groundwater should be lowered a minimum of 12 inches below the bottom of site removals/over-excavations. A typical dewatering method consists of a gravel filled sump hole at a low point in the excavation provided with a submersible pump. Dewatering discharge location(s) and onto public stormwater drainage facility(ies) should be pre-approved by the governing agencies. Seepage and standing water can also result in soft and yielding bottom ofremovals and over-excavations requiring stabilization with placing a ¾-inch crushed rock mat, well- consolidated and adequately interlocked by track walking with heavy construction equipment. More significant seepage may also require installing a subdrain system consisting of a perforated (minimum 4-inch diameter Schedule 40) pipe surrounded with ¾-inch crushed rocks all wrapped in filter fabric. Specific recommendations should be given by the project geotechnical engineer at the time of remedial grading operations based on the actual field exposures. 8. Retaining Wall Back Drainage System: A well developed back drainage system should be constructed behind all project site retaining walls. The wall back drainage system should consist of a minimum 4-inch diameter, Schedule 40 (SDR 35) perforated pipe surrounded with a minimum of 1 ½ cubic feet per foot of ¾-crushed rocks ( 12 inches wide by 18 inches deep) installed at the depths of the wall foundation level and wrapped in filter fabric (Mirafi 140N). If Cal trans Class 2 permeable aggregate is used in lieu of the crushed rocks, the filter fabric can be deleted. The wall back drain should be installed at suitable elevations to allow for adequate fall via a non-perforated solid pipe (Schedule 40 or SDR 35) to an approved outlet. Protect pipe outlets as appropriate. All wall back drain pipes and outlets should be shown on the final as-build plans. Limited Geotechnical Investigation Proposed New Attached Building Additions, 3357 Adams Street, Carlsbad June 14, 2021 Page 22 A wall back drain system schematic is depicted on the enclosed Typical Retaining Wall Back Drainage, Figure 13. Provide appropriate waterproofing where applicable as indicated on the project pertinent construction plans. 9. Surface Drainage and Erosion Control: A critical element to the continued stability of project existing and new graded building additions/extensions pads, and site improvement surfaces is an adequate stormwater and surface drainage control. Surface water should not be allowed to flow toward and pond near the building foundations or impact the graded construction and improvement sites. Concentrated flow should be avoided and positive drainage (minimum 5%) should be established during fine grading efforts away from the building and site improvements onto a suitable drainage collection and disposal facility. Vegetated or grass-lined swales should be constructed as appropriate and surface drainage control facilities provided as shown on the project approved drawings. Roof gutters and area drains should be installed. Over- watering of the site landscaping should also not be allowed. Only the amount of water to sustain vegetation should be provided. Temporary erosion control facilities and silt fences should be installed during the construction phase periods and until landscaping is fully established. Site drainage improvements should be completed as shown on the project approved site/erosion control plans. 10. Engineering Observations and Compaction Testing: All earthwork operations including excavations, bottom of removals and over-excavations, suitability of earth deposits used as compacted fills and backfills, fill/backfill processing, placement and compaction procedures should be continuously observed and tested by the project geotechnical consultant and presented in a final compaction report. Engineering properties of finished bearing and subgrade soils should be confirmed in the final rough pad grading compaction report. Geotechnical engineering observations and testing should include but are not limited to the following: * Initial observation -After demolition, clearing and grading limits have been staked but before excavation starts. * Bottom of removals/ over-excavation observations -After bottom of excavation/ over- excavation is exposed and prepared to receive fill or backfill, but before fill or backfill is placed. Limited Geotechnical Investigation Proposed New Attached Building Additions, 3357 Adams Street, Carlsbad June 14, 2021 Page 23 * Temporary excavation and trenching observations -After the excavation is started but before the vertical depth of excavation is more than 5 feet. Local and Cal-OSHA safety requirements for open excavations apply. * Fill/backfill observation -After the fill/backfill placement is started but before the vertical height of fill/backfill exceeds 2 feet. A minimum of one test shall be required for each 100 lineal feet maximum in every 2 feet vertical gain, with the exception of wall backfills where a minimum of one test shall be required for each 30 lineal feet maximum. Plastic silty to clayey soils are not suitable for wall backfills and good quality sandy granular soils should be used for this purpose. Wall backfills should be mechanically compacted to a minimum of90% compaction levels unless otherwise specified or directed in the field. Finish rough and final pad grade tests shall be required regardless of fill thickness. * Foundation trench and subgrade soils observation -After the foundation trench excavations and prior to the placement of steel reinforcing for proper moisture and specified compaction levels. * Geotechnical foundation/slab steel observation -After the steel placement is completed but before the scheduled concrete pour. * Underground utility, plumbing and storm drain trench observation -After the trench excavations but before placement of pipe bedding or installation of the underground facilities. Local and Cal-OSHA safety requirements for open excavations apply. Observations and testing of pipe bedding may also be required by the project geotechnical engineer. * Underground utility, plumbing and storm drain trench backfill observation -After the backfill placement is started above the pipe zone but before the vertical height of backfill exceeds 2 feet. Testing of the backfill within the pipe zone may also be required by the governing agencies. Pipe bedding and backfill materials shall conform to the governing agencies' requirements and project soils report if applicable. Plastic silty to clayey soils are not suitable for trench backfills. All trench backfills should be mechanically compacted to a minimum of 90% compaction levels unless otherwise specified. Plumbing trenches more than 12 inches deep maximum under the floor slabs should also be mechanically compacted and tested for a minimum of 90% compaction levels. Flooding or jetting techniques as a means of compaction method should not be allowed. * Improvements base and sub grade observation -Prior to the placement of concrete for proper moisture and specified compaction levels. Limited Geotechnical Investigation Proposed New Attached Building Additions, 3357 Adams Street, Carlsbad B. Footings and Slab-on-Grade Floor Foundations June 14, 2021 Page 24 The following recommendations are consistent with the anticipated silty sand (SM/SW) bearing and sub grade soils ranging to very low expansion potential ( expansion index less than 20 based on ASTM D4829 classification). All design recommendations should be further confirmed and/or revised as necessary at completion ofremedial grading works based on actual testing of final bearing and sub grade soils: 1. All foundations should be supported on minimum 90% compacted fills, placed in accordance with the requirements of this report. There should be at least 24 inches of well-compacted fills below bottom of the deepest footing(s), unless otherwise approved. Foundation trenching should be completed in substantial conformance with the Typical Foundation Fonnwork Detail included in the attached Figure 11. 2. The new building additions/extensions may be supported on a system of perimeter and interior continuous strip and spread pad footings. Perimeter and interior continuous footings should be sized at least 15 inches wide and 18 inches deep for single and 2-story structures. Spread pad footings, if any, should be at least 30 inches square and 18 inches deep Footing depths are measured from the lowest adjacent ground surface, not including the sand/gravel layer beneath floor slabs. Exterior continuous grade beam footings should enclose the entire building perimeter. Flagpole footings also need to be tied together, if the footing depth is less than 6 feet below rough finish grade. 3. Continuous interior and exterior footings should be reinforced with a minimum of four #4 reinforcing bars. Place 2-#4 bars 3 inches above the bottom of the footing and 2-#4 bars 3 inches below the top of the footing. Reinforcement details for spread pad footings should be provided by the project architect/structural engineer. 4. Existing building footings should be tied to the new adjacent addition footings with minimum 24 inches long #4 dowels at 16 inches on center maximum with 6 inches deep drill and epoxy grout to existing footings and a minimum of 18 inches into new footings, as schematically shown on the attached Figure 12. New slab edge( s) adjacent to existing building footings/slabs, if any and where they occur, should also be provided with a minimum 12 inches wide by 12 inches deep thickened edge reinforced with minimum 1-#4 bar top and bottom, and tied together as specified, with minimum #4 dowels at same spacing as the new slab reinforcement. Actual details per structural designs/plans. 5. All interior slabs should be a minimum 4.5 inches in thickness, reinforced with #3 reinforcing bars spaced 16 inches on center each way, placed near the slab mid-height. Limited Geotechnical Investigation Proposed New Attached Building Additions, 3357 Adams Street, Carlsbad June 14, 2021 Page 25 Interior slabs should be underlain by 4 inches of clean sand (SE 30 or greater) which is provided with a well performing moisture barrier/vapor retardant (minimum 10-mil Stego) placed mid-height in the sand. Alternatively, a 4-inch thick base of compacted ½-inch clean aggregate provided with the vapor barrier (minimum 15-mil Stego) in direct contact with (beneath) the concrete may also be considered provided a concrete mix which can address bleeding, shrinkage and curling is used. Provide "softcut" contraction/control joints consisting of sawcuts spaced 10 feet on centers each way for all interior slabs. Cut as soon as the slab will support the weight of the saw and operate without disturbing the final finish which is normally within two hours after final finish at each control joint location or 150 psi to 800 psi. The sawcuts should be minimum 1-inch in depth but should not exceed 1 ¼-inches deep maximum. Anti-ravel skid plates should be used and replaced with each blade to avoid spalling and raveling. A void wheeled equipment across cuts for at least 24 hours. Provide re-entrant comer (270 degrees comers) reinforcement for all interior slabs consisting of minimum two, 6 feet long #3 bars at 12 inches on center with the first bar placed 3 inches from the re-entrant comer. Re-entrant corners will depend on slab geometry and/or interior column locations. The enclosed Figure 14 may be used as a general guideline. 6. Foundation trenching efforts are expected to cause disturbed bottom of trenches and may result in uneven/unsmooth trench sidewalls. Disturbed bottom of trenches should be recompacted in-place using a wacker and disturbed trench side walls, if developed, should be neatly removed (widened areas should be filled with concrete as a part of the footing pour) prior to steel placement. 7. Foundation trenches and slab subgrade soils should be observed and tested for proper moisture and specified compaction levels and approved by the project geotechnical consultant prior to the placement of steel reinforcement or concrete pour. C. Soil Desi2n Parameters The following soil parameters are based on tested representative samples of onsite earth deposits and should be considered in the project designs, where appropriate and as applicable: 1. Design soil unit weight = 124 pcf. 2. Design angle of internal friction of soil = 32 degrees. 3. Design active soil pressure for retaining structures = 38 pcf (EFP), level backfill, cantilever, unrestrained walls. Limited Geotechnical Investigation Proposed New Attached Building Additions, 3357 Adams Street, Carlsbad June 14, 2021 Page 26 4. Design at-rest soil pressure for retaining structures === 58 pcf (EFP), non-yielding, restrained walls. 5. Design passive soil resistance for retaining structures === 400 pcf (EFP), level ground surface on the toe side (soil mass on the toe side extends a minimum of 10 feet or 3 times the height of the surface generating passive resistance). 6. Design coefficient of friction for concrete on soils=== 0.39. 7. Net allowable foundation pressure=== 2000 psf. 8. Allowable lateral bearing pressure (all structures except retaining walls)=== 200 psf/ft. Notes: * An additional seismic force due to seismic increments of earth pressure should also be considered in the project designs, if appropriate and where applicable. A seismic lateral inverted triangular earth pressure of 18 pcf (EFP), acting at 0.6H (H is the retained height) above the base of the wall should be considered. Alternatively, seismic loading based on Mononobe-Okake (M-O) coefficients may be considered for seismic force due to seismic increments of earth pressure. The following relationships and design values are appropriate: TABLE13 Wall Total Seismic Lateral KA Ko K.h KAE KOE y Condition Lateral Pressure Pressure (pct) Unrestrained PAE=PA + PAE 8PAE=%KhiH2 0.31 -0.15 0.46 -124 Restrained POE=PO + POE 8PoE=KhiH2 -0.47 0.15 -0.62 124 * Use a minimum safety factor of 1.5 for wall over-turning and sliding stability. However, because large movements must take place before maximum passive resistance can be developed, a minimum safety factor of 2 may be considered for sliding stability particularly where sensitive structures and improvements are planned near or on top of retaining walls. * When combining passive pressure and frictional resistance the passive component should be reduced by one-third. The upper 6 inches of ground surfaces should not be included in the design for passive soil resistance, unless otherwise noted or specified. * The indicated net allowable foundation pressure provided herein was determined based on a minimum 12 inches wide by 12 inches deep footings and may be increased by 20% for each additional foot of depth and 20% for each additional foot of width to a maximum of 5500 psf, if needed. The allowable foundation pressures provided herein also apply to dead plus live loads and may be increased by one-third for wind and seismic loading. Limited Geotechnical Investigation Proposed New Attached Building Additions, 3357 Adams Street, Carlsbad June 14, 2021 Page27 * The lateral bearing earth pressures may be increased by the amount of designated value for each additional foot of depth to a maximum 1500 pounds per square foot. D. Exterior Concrete Slabs / Flatworks 1. All exterior slabs ( concrete decking, walkways, patios, etc.) supported on very low expansive sub grade soils should be a minimum of 4 inches in thickness, reinforced with #3 bars at 18 inches on center in both directions placed mid-height in the slab. Remedial subgrade over-excavations, ground preparation and recompaction shall be required for all site improvements including exterior slabs, stair cases and patio decks as a part of the project grading operations, and as specified in this report. Additionally, subgrade soils underneath the exterior slabs and site improvements should be moisture reconditioned and recompacted to minimum 90% compaction levels at the time of fine grading and before placing the slab reinforcement. 2. Reinforcements lying on subgrade will be ineffective and shortly corrode due to lack of adequate concrete cover. Reinforcing bars should be correctly placed extending through the construction joints tying the slab panels. In construction practices where the reinforcements are discontinued or cut at the construction joints, slab panels should be tied together with minimum 18 inches long #3 dowels at 18 inches on centers placed mid-height in the slab (9 inches on either side of the joint). 3. Provide "tool joint" or "softcut" contraction/control joints spaced 10 feet on center (not to exceed 12 feet maximum) each way. The larger dimension of any panel shall not exceed 125% of the smaller dimension. Tool or cut as soon as slab will support weight, and can be operated without disturbing the final finish which is normally within 2 hours after final finish at each control joint location or 150 psi to 800 psi. Tool or softcuts should be a minimum of ¾-inch but should not exceed I-inch deep maximum. In case of softcut joints, anti-ravel skid plates should be used and replaced with each blade to avoid spalling and raveling. A void wheeled equipment across cuts for at least 24 hours. Joints shall intersect free-edges at a 90° angle and shall extend straight for a minimum of 1 ½ feet from the edge. The minimum angle between any two intersecting joints shall be 80°. Align joints of adjacent panels. Also, align joints in attached curbs with joints in slab panels. Provide adequate curing using approved methods ( curing compound maximum coverage rate= 200 sq. ft./gal.). 4. All exterior slab designs should be confirmed in the final as-graded compaction report. 5. Sub grade soils should be tested for proper moisture and specified compaction levels and approved by the project geotechnical consultant prior to the placement of concrete. Limited Geotechnical Investigation Proposed New Attached Building Additions, 3357 Adams Street, Carlsbad E. General Recommendations June 14, 2021 Page 28 1. The minimum foundation design and steel reinforcement provided herein are based on soil characteristics and are not intended to be in lieu of reinforcement necessary for structural consideration. 2. Adequate staking and grading control is a critical factor in properly completing the recommended remedial and site grading operations. Grading control and staking should be provided by the project grading contractor or surveyor/civil engineer, and is beyond the geotechnical engineering services. Staking should apply the required setbacks shown on the approved plans and conform to setback requirements established by the governing agencies and applicable codes for off-site private and public properties and property lines, utility easements, right-of-ways, nearby structures and improvements, leach fields and septic systems, and graded embankments. Inadequate staking and/or lack of grading control may result in illegal encroachments or unnecessary additional grading which will increase construction costs. 3. Open or backfilled trenches parallel with a footing shall not be below a projected plane having a downward slope of I-unit vertical to 2 units horizontal (50%) from a line 9 inches above the bottom edge of the footing, and not closer than 18 inches from the face of such footing. The Typical Trench Adjacent to Foundation is provided in the enclosed Figure 15 and may be used as a general guideline. 4. Where pipes cross under-footings, the footings shall be specially designed. Pipe sleeves shall be provided where pipes cross through footings or footing walls, and sleeve clearances shall provide for possible footing settlement, but not less than I-inch all around the pipe. A schematic detail entailed Pipes Through or Below Foundation is included on the enclosed Figure 15. 5. Expansive clayey soils should not be used for backfilling of any retaining structure. All retaining walls should be provided with a 1: 1 wedge of granular, compacted backfill measured from the base of the wall footing to the finished surface and a well-constructed back drain system as shown on the enclosed Typical Retaining Wall Back Drainage, Figure 13. Planting large trees behind site retaining walls should be avoided. 6. All underground utility and plumbing trenches should be mechanically compacted to a minimum of90% (95% in public right-of-way) of the maximum dry density of the soil unless otherwise specified or required by the governing agencies. Care should be taken not to crush the utilities or pipes during the compaction of the soil. Very low expansive, granular import backfill soils should be used. Trench backfilJ materials and compaction beneath pavements within the public right-of-way shall conform to the requirements of . . governmg agencies. Limited Geotechnical Investigation Proposed New Attached Building Additions, 3357 Adams Street, Carlsbad June 14, 2021 Page 29 7. Finish ground surfaces immediately adjacent to the building foundations shall be sloped away from the building at a minimum 5% for a minimum horizontal distance of 10 feet measured perpendicular to face of the building wall (CBC 1804.4 Site Grading). If physical obstructions or property lines prohibit 10 feet of horizontal distance, a 5% slope shall be provided with an alternative method for diverting water away from the foundation. Swales used for this purpose shall be sloped not less than 2% where located within 10 feet of the building foundation. Impervious surfaces (concrete sidewalks) within 10 feet of the building foundation shall also be sloped at minimum 2% away from the building. 8. Care should be taken during the construction, improvements, and fine grading phases not to disrupt the designed drainage patterns. Rooflines of the buildings should be provided with roof gutters. Roof water should be collected and directed away from the buildings and structures to a suitable location. 9. All foundation trenches should be observed to ensure adequate footing embedment and confirm competent bearing soils. Foundation and slab reinforcements should also be inspected and approved by the project geotechnical consultant. 10. The amount of shrinkage and related cracks that occur in the concrete slab-on-grades, flatwork and driveways depend on many factors, the most important of which is the amount of water in the concrete mix. The purpose of the slab reinforcement is to keep normal concrete shrinkage cracks closed tightly. The amount of concrete shrinkage can be minimized by reducing the amount of water in the mix. To keep shrinkage to a minimum the following should be considered: * Use the stiffest mix that can be handled and consolidated satisfactorily. * Use the largest maximum size of aggregate that is practical. For example, concrete made with %-inch maximum size aggregate usually require about 40-lbs. more (nearly 5-gal.) water per cubic yard than concrete with 1-inch aggregate. * Cure the concrete as long as practical. The amount of slab reinforcement provided for conventional slab-on-grade construction considers that good quality concrete materials, proportioning, craftsmanship, and control tests where appropriate and applicable are provided. 11. A preconstruction meeting between representatives of this office, the property owner or planner, city inspector as well as the grading contractor/builder is recommended in order to discuss grading and construction details associated with site development. Limited Geotechnical Investigation Proposed New Attached Building Additions, 3357 Adams Street, Carlsbad XII. GEOTECHNICAL ENGINEER OF RECORD (GER) June 14, 2021 Page 30 §1'1§ Geotechnical Solutions, Inc. is the geotechnical engineer of record (GER) for providing a specific scope of work or professional service under a contractual agreement unless it is terminated or canceled by either the client or our firm. In the event a new geotechnical consultant or soils engineering firm is hired to provide added engineering services, professional consultations, engineering observations and compaction testing, SMSGeotechnical Solutions, Inc. will no longer be the geotechnical engineer of the record. Project transfer should be completed in accordance with the California Geotechnical Engineering Association (CGEA) Recommended Practice for Transfer of Jobs Between Consultants. The new geotechnical consultant or soils engineering firm should review all previous geotechnical documents, conduct an independent study, and provide appropriate confirmations, revisions or design modifications to his own satisfaction. The new geotechnical consultant or soils engineering firm should also notify in writing §1':I§ Geo technical Solutions, Inc. and submit proper notification to the City of Carlsbad for the assumption of responsibility in accordance with the applicable codes and standards. XIII. LIMITATIONS The conclusions and recommendations provided herein have been based on available data obtained from the review of pertinent reports and plans, limited subsurface explorations well as our experience with the soils and formational materials located in the general area. The materials encountered on the project site and utilized in our laboratory testing are believed representative of the total area; however, earth materials may vary in characteristics between excavations. Of necessity, we must assume a certain degree of continuity between exploratory excavations and/or natural exposures. It is necessary, therefore, that all observations, conclusions, and recommendations be verified during the site excavations and construction operations. In the event discrepancies are noted, we should be contacted immediately so that an observation can be made and additional recommendations issued if required. The recommendations made in this report are applicable to the site at the time this report was prepared. It is the responsibility of the owner/developer to ensure that these recommendations are carried out in the field. It is almost impossible to predict with certainty the future performance of a property. The future behavior of the site is also dependent on numerous unpredictable variables, such as earthquakes, rainfall, and on-site drainage patterns. Limited Geotechnical Investigation Proposed New Attached Building Additions, 3357 Adams Street, Carlsbad June 14, 2021 Page 31 The firm of §II§ Geotechnical Solutions, Inc., shall not be held responsible for changes to the physical conditions of the property such as addition of fill soils or changing drainage patterns which occur without our observation or control. This report should be considered valid for a period of one year and is subject to review by our finn following that time. If significant modifications are made to your tentative construction plan, especially with respect to finish pad elevations and room addition final layout, this report must be presented to us for review and possible revision. This report is issued with the understanding that the owner or his representative is responsible for ensuring that the information and recommendations are provided to the project architect/structural engineer so that they can be incorporated into the plans. Necessary steps shall be taken to ensure that the project general contractor and subcontractors cany out such recommendations during construction. The project geotechnical engineer should be provided the opportunity for a general review of the project final design plans and specifications in order to ensure that the recommendations provided in this report are properly interpreted and implemented. If the project geotechnical engineer is not provided the opportunity of making these reviews, he can assume no responsibility for misinterpretation of his recommendations. The property owner(s) should be aware of the potential development of cracks in all concrete surfaces such as floor slabs and exterior stucco associated with normal concrete shrinkage during the curing process. These features depend chiefly upon the condition of concrete and weather conditions at the time of construction and mostly do not reflect detrimental ground movement. Hairline stucco cracks will often develop at windows/door corners, and floor surface cracks up to 1/a-inch wide in 20 lineal feet may develop as a result of normal concrete shrinkage ( according to the American Concrete Institute). SM§ Geotechnical Solutions, Inc., warrants that this report has been prepared within the limits prescribed by our client with the usual thoroughness and competence of the engineering profession. No other warranty or representation, either expressed or implied, is included or intended. Once again, should any questions arise concerning this report, please do not hesitate to contact this office. Reference to our Project No. GI-21-05-131 will help to expedite our response to your inquiries. Limited Geotechnical Investigation Proposed New Attached Building Additions, 3357 Adams Street, Carlsbad We appreciate this opportunity to be of service to you. 61'1§ Geotechnical Solutions, Inc. hdi S. Shariat, GE #2885 Principal Project Geologist Staff Geologist Distribution: Addressee (3, email) 681§ GEOTECHNICAL SOLUTIONS, INC. June 14, 2021 Page 32 REFERENCES -Annual Book of ASTM Standards, Section 4-Construction, Volume 04.08: Soil and Rock (I); D420 -D5876, 2019. -Annual Book of ASTM Standards, Section 4 -Construction, Volume 04.09: Soil and Rock (II); D5877 -Latest, 2019. -Highway Design Manual, Cal trans. Fifth Edition. Corrosion Guidelines, Caltrans, Version 1.0, September 2003. -California Building Code (CBC), California Code of Regulations Title 24, Part 2, Volumes 1 & 2, 2019, International Code Council. -"The Green Book" Standard Specifications For Public Works Construction, Public Works Standards, Inc., BNi Building News, Latest Edition. -California Geological Survey, 2008 (Revised), Guidelines for Evaluating and Mitigating Seismic Hazards in California, Special Publication 117 A, 108p. California Department of Conservation, Division of Mines and Geology (California Geological Survey), 1986 (revised), Guidelines for Preparing Engineering Geology Reports: DMG Note 44. California Department of Conservation, Division of Mines and Geology (California Geological Survey), 1986 (revised), Guidelines to Geologic and Seismic Reports: DMG Note 42. EQFAULT, Ver. 3.00, 1997, Deterministic Estimation of Peak Acceleration from Digitized Faults, Computer Program, T. Blake Computer Services and Software. -EQSEARCH, Ver 3.00, 1997, Estimation of Peak Acceleration from California Earthquake Catalogs, Computer Program, T. Blake Computer Services and Software. -Tan S.S. and Kennedy, M.P., 1996, Geologic Maps of the Northwestern Part of San Diego County, California, Plate(s) 1 and 2, Open File-Report 96-02, California Division of Mines and Geology, 1 :24,000. -"Proceeding of The NCEER Workshop on Evaluation of Liquefaction Resistance Soils," Edited by T. Leslie Youd and Izzat M. Idriss, Technical Report NCEER-97-0022, Dated December 31, 1997. -"Recommended Procedures For Implementation of DMG Special Publication 117 Guidelines For Analyzing and Mitigation Liquefaction In California," Southern California Earthquake Center; USC, March 1999. REFERENCES (continued) "Soil Mechanics," Naval Facilities Engineering Command, DM 7.01. -"Foundations & Earth Structures," Naval Facilities Engineering Command, DM 7.02. -"Introduction to Geotechnical Engineering, Robert D. Holtz, William D. Kovacs. -"Introductory Soil Mechanics and Foundations: Geotechnical Engineering," George F. Sowers, Fourth Edition. -"Foundation Analysis and Design," Joseph E. Bowels. -Caterpillar Performance Handbook, Edition 29, 1998. -Jennings, C.W., 1994, Fault Activity Map of California and Adjacent Areas, California Division of Mines and Geology, Geologic Data Map Series, No. 6. Kennedy, M.P., 1977, Recency and Character of Faulting Along the Elsinore Fault Zone in Southern Riverside County, California, Special Report 131, California Division of Mines and Geology, Plate 1 (East/West), 12p. Kennedy, M.P. and Peterson, G.L., 1975, Geology of the San Diego Metropolitan Area, California: California Division of Mines and Geology Bulletin 200, 56p. -Kennedy, M.P. and Tan, S.S., 1977, Geology of National City, Imperial Beach and Otay Mesa Quadrangles, Southern San Diego Metropolitan Area, California, Map Sheet 24, California Division of Mines and Geology, 1 :24,000. -Kennedy, M.P., Tan, S.S., Chapman, R.H., and Chase, G.W., 1975, Character and Recency of Faulting, San Diego Metropolitan Areas, California: Special Report 123, 33p. -"An Engineering Manual For Slope Stability Studies," J.M. Duncan, A.L. Buchignani and Marius De Wet, Virginia Polytechnic Institute and State University, March 1987. -"Procedure To Evaluate Earthquake-Induced Settlements In Dry Sandy Soils," Daniel Pradel, ASCE Journal Of Geotechnical & Geoenvironmental Engineering, Volume 124, #4, 1998. -"Minimum Design Loads For Buildings and Other Structures," ASCE 7-16, American Society of Civil Engineers (ASCE). -"Seismic Constraints on The Architecture of The Newport-Ingelwood/Rose Canyon Fault: Implications For The Length And Magnitude of Future Earthquakes," Sahakian, V., Bormann, J.,Driscoll, N., Harding, A. Kent, G. Wesnousky, S. (2017), AGU. doi:10.1002/2016 JB 013467. z z 0 0 0 0 lfl .... M M 18 \ \ \ ' 0 TOPO! map printed on 05/24/21 from "SanDlego.tpo" and "Untitled.tpg" 117.35000° w 117.33333° w 117. 35000° w 117.33333° w 't:::========f:~=======:::lMU 9 I I I 11!°° FEET I I I I ~3!hn I I I I fOOOm Printtd from TOPO! C!999 Wildflower Produ<tioru ("""'.topo.com) WGS84 117.31667° W WGS84 117.31667° W GEO TECHNICAL SITE PLAN 3357 ADAMS STREET, CARLSBAD, CA SCALE: l" = 20' 0 q 0 ~ Fl SMS GEOTECHNICAL SOLUTIONS INC 5931 Sea Lion Place, Suite 109 Carlsbad, CA 92010 O' 20' Uaf / Qs / Qop EX PCXJ.. TO BE REFINS I-ED ~ T ~ ~ TI0.00' t A -z. RES! t\CE A' I /Z7 •~ b I 0 LC) (") ~ I co N Fl (0 I 0 N ADAMS ST . Legend ~ Produced Building Location ~ Geologic Cross Section Approximate Location -of Test Pit Uaf Undocumented Fill Qs Topsoil Qop Old Paralic Deposits 5'-0" Uaf/Qs /Q p -0 q 0 ~ Fl EX DRIVEWAY I ~ MATERIAL I DELIVERY & STORAGE ~ SOLID WASTE MANAGEMENI ~ SPILL PREVENTION ProjectNumber: GI-21-05-131 Figure Number: 2 ;<EV TO BORING / TEST PIT LOGS DRILLING & SAMPLING SYMBOLS: !Z'j Split Spoon -1-3/8" I.D., 2" O.D., Unless otherwise noted HS: Hollow Stem Auger □ Chunk Sample ST: Thin-Walled Tube -2" O.D., Unless otherwise noted PA: Power Auger v Sandcone Density Test ~ Ring Sampler-2.375" I.D., 2.5" O.D., Unless otherwise noted HA: Hand Auger DB: Diamond Bit Coring -4", N, B RB: Rock Bit ■ Bulk Sample or Auger Sample WB: Wash Boring or Mud Rotary The number of blows required to advance a standard 2-inch 0.D. split-spoon sample {SS) the last 12 inches of the total 18-inch penetration with a 140-pound hammer falling 30 inches is considered the "Standard Penetration" or "N-value". For 2.5" 0.D. ring samplers (RS) the penetration value is reported as the number of blows required to advance the sampler 12 inches using a 140-pound hammer falling 30 inches, reported as "blows per foot" and is not considered equivalent to the "Standard Penetration" or "N-value". WATER LEVEL MEASUREMENT SYMBOLS WL: Water Level WCI: Wet Cave in OCI: Dry Cave in AB: After Boring WS: WO: BCR: ACR: While Sampling While Drilling Before Casing Removal After Casing Removal N/E: Not Encountered Water levels indicated on the boring logs are the levels measured In the borings at the times indicated. Groundwater levels at other times and other locations across the site could vary. In pervious soils, the indicated levels may reflect the location of groundwater. In low permeability soils, the accurate determination of groundwater levels may not be possible with only short-term observation. DESCRIPTIVE SOIL CLASSIFICATION: Soil classification is based on the unified classification system. Coarse Grained Soils have more than 50% of their dry weight retained on a #200 sieve; their principal descriptors are: boulders, cobbles, gravel or sand. Fine Grained Soils have less than 50% of their dry weight retained on a #200 sieve; they are principally described as clays if they are plastic, and silts If they are slightly plastic or non-plastic. Major constituents may be added as modifiers and minor constituents may be added according to relative proportions based on grain size. In addition to gradation, coarse-grained soils are defined on the basis of their in-place relative density and fine-grained soils on the basis of their consistency. CONSISTENCY OF FINE-GRAINED SOILS RELATIVE DENSITY OF COARSE-GRAINED SOILS Unconfined Standard Standard Compressive Penetration or N-Penetration or N-Ring Sampler (RSI Streng1h, gu, 2sf value (SS) Blows[Ft. Consisten!,Jt value (SS) Blows[Ft. Blows[Ft. Relative Densi~ < 500 <2 Very Soft 0-3 0-6 Very Loose 500-1000 2-3 Soft 4-9 7-18 Loose 1001 -2000 4-6 Medium Stiff 10-29 19-58 Medium Dense 2001-4000 7 -12 Stiff 30-49 59-98 Dense 4001-8000 13-26 Very Stiff SO+ 99+ Very Dense 8000 + 26+ Hard RELATIVE PROPORTION OF SAND AND GRAVEL GRAIN SIZE TERMINOLOGY Descriptive Term(sl of other constituents Trace With Modifiers Percent of Dry Weight < 15 M ajor Component of Sample Boulders Particle Size Over 12 in. (300 mm) 15-29 > 30 RELATIVE PROPORTION OF FINES Descriptive Term(sl of other constituents Trace With Modifiers Percent of Dry Weight < 15 15-12 > 12 Cobbles Gravel Sand Silt or Clay Term Non-plastic Low Medium High 12 in. to 3 in. {300 mm to 75 mm) 3 in. to #4 sieve (75 mm to 4.75 mm) #4 Sieve to #200 Sieve (4.75 mm to 0.075 mm) Passing #200 Sieve {0.075 mm) PLASTICITY DESCRIPTION Plasticity indell 0 1-10 11-30 30+ ~~~ Geotechnical Solutions, Inc. UNIFIED SOIL CLASSIFICATION SYSTEM (USCS) Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests' Soll Classification Group Group Name S mbol Gravels Clean G!:!vels C, 2: 4 and 1 s ~ s 3' GW Well-graded gravel' More than 50% of coarse Less than S" fines' Not meeting above gradation for GW GP Poorly graded gravel' Coarse Grained Soils fraction retained on #4 Gravels with Fines Fines classify as ML or MH GM Silty gravel'·G,w More than SO% sieve More than 12" fines' Fines classify as CL or CH GC Clayey gravel'·G." retained on #200 Cleansainds c, 2: 6 and 1 s C, s 3' sieve• Sands Less than 5% fines0 Not meeting above gradation for SW SO% or more of coarse Sands with Anes Fines classify as ML or MH SW Well-graded sand' SP Poorly graded sand' SM Silty sandG,HJ fraction passes #4 sieve More than 12% fines• Fines classify as CL or CH SC Clayey sandG•"·' Inorganic Pl> 7 and plots on or above #A# line' Sitts and Claiys Pl< 4 and plots below NA• line' CL Lean day":,. ML Sltt(-~M Fine Grained Solis Uquld limit less than SO organic Liquid Limit -oven dried Liquid Limit-not dried 50% or more passes Pl plots on or above •An line the #200 sieve• Sitts and Clays inorganic Pl plots below "A" line <0.75 Ol Organic clay'(,~"'·• Organic sllt"-~"-0 CH Fat clay":'-<M MH Liquid limit 50 or more organic Liquid Limit-oven dried Liquid Limit-not dried <0.75 OH Organic claf•~M.• Organic silt"-1.M.O Highly organic sells Primarily organic matter, dark In color, and organic odor PT Peat * For soils having 5 to 12 % passing the No. 200 sieve, use a dual symbol such as GW-GC. A Based on the material passing the 3 in. (75 mm) sieve. • If field sample contained cobbles or boulders, or both, add "with cobbles or boulders, or both• to group name. c Gravels with 5% to 12% fines require dual symbols: GW-GM well-graded gravel with silt, GW-GC well-graded gravel with clay, GP-GM poorly graded gravel with silt, GP-GC poorly graded gravel with clay. 0 Sands with 5% to 12% fines require dual symbols: SW-SM well-graded sand with silt, SW-SC well-graded sand with clay, SP-SM poorly graded sand with silt, SP-SC poorly graded sand. For classifications of fine-grained soils and fine-grained fraction of coarse- grained soils. Equation of "A" line. Horizontal at Pl=4 to LL=25.S, then Pl=0.73 (LL-20). Equation of "U" line. Vertical at LL=16 to P1=7, then Pl = 0.9 (LL-8) 60 so ,::-40 Cl. X QJ TI E 30 ;:; ·o ,=, V, "' ii: 20 10 7 4 0 r If soil contains 2:15% sand, add "with sand" to group name. 6 If fines classify as CL-ML, use dual symbol GC-GM, or SC-SM H If fines are organic, add •with organic fines" to group name. If soil contains 2:15% gravel, add •with gravel" to group name. If Atterberg limits plot in shaded area, soll is a CL-ML, silty clay. x If soil contains 15% to 29% plus No. 200, add "with sand" or "with gravel" whichever is L If soil contains 2:30% plus No. 200 predominantly sand, add "sandy" to group name. M lf soil contains 2:30% plus No. 200 predominantly gravel, add "gravelly" to group name. N Pl 2:4 and plots on or above "A" line. 0 Pl <4 or plots below "A" line. P Pl plots on or above "A" line. a Pl plots below "A" line l H 0 10 16 20 30 40 50 70 100 Liquid Limit (LL) ~IM~ Geotechnica l Solutions, Inc. SMS Geotechnical Solutions, Inc. PROJECT: Proposed New Attached Building Test Pit: TP-1 CLIENT: Shane Garst PROJECT No.: Gl-21-05-131 PROJECT LOCATION: 3357 Adams Street. Carlsbad Date Excavated: -----'5/_26-'--/2_1_ Logged By: --~C-~M=·-- Equipment: Mini Excavator (KUBOTA KX121-2). Remarks: No cavinl!. No l!roundwater. (.J DEPTH ~8 (ft} ~ ..J 0 MATERIAL DESCRIPTION IX ARTIFICIAL FILL{Uaf): -x 1X X 2X X Silty sand. Tan to green-brown color. Fine-grained. Slightly moist to moist. Loose to very loose. Contains roots/ rootlets and construction/ demolition debris. en t.i en ;:j SM I 6 --x At 2.5 feet, encountered abandoned 2.5-inch diameter ~/ steel pipe (may be an abondand water line). 3 ,.._S_T_-l __________________ ~, --. __ l ___ 1_9-4--1_01_.6-4-_-~,__9_5 -I TOPSOIL {Os): - Silty clayey. Dark brown color. Sandy. Very moist to 4 -1566,G666,I-, wet. Soft. Plastic. 1 Contains roots/ rotlets. Mottled with dark gray color. " ~ " " " " ~ ~ " -5 " " -: ' . -:::•, -:-_.·: : .. •', .-·.·.·: ·. ,: :, ._.,. ■ BULK SAMPLE ST-2 OLD PARALIC DEPOSITS {Oop): Silty clay to clayey silt. Olive-green to brown color. Highly weathered. Moist to very moist. Firm. At 4.5 feet, color changed to light olive green. ST-3 Silty sandstone. Light olive-tan color. Damp. Fine to medium-grained. Dense to very dense. Slightly to moderately cemented. ST-4 Bottom of test pit at 6.0 feet. □ CHUNK W NUCLEAR GAUGE n GROUND DENSITY T TEST V WATER CL ~ -. __ l __ ~, -+----+-~--1 • 123.5 IOOt 78 l II 119.6 70 SM/SI ~ _ ___._ _ ___._ _ ___._ _ _._ _ _.__--4 FIGURE 3 SMS Geotechnical Solutions, Inc. Test Pit : TP-2 PROJECT: Proposed New Attached Building CLIENT: Shane Garst PROJECT No.: GI-21-05-131 PROJECT LOCATION: 3357 Adams Street. Carlsbad Date Excavated: 5/26/21 Logged By: C.M. Equipment: Mini Excavator (KUBOTA KX121-2). Remarks: No caving. No ITToundwater. u en OJ LU!-t:c ~~ ""o DEPTH ~8 ~z 0-u _, OJ ~~~ ~.e "'f-MATERIAL DESCRIPTION """-f-(n~ l;/~* en ::0>-!:!2z e_. >-~ :5z~ (ft) ;;i .J ;:i <(I-00 0,: );!~ @~- 0 "' ::.u 0 o< X ARTIFICIAL FILL {at): ~ -X Sand to silty sand. Light gray color. Appears imported ~ 1 ~ wall backfill. Damp. Very loose. Medium-grained. SP Poorly graded. Micaceous. ... -ST-5 2 -[><---------------------------------------- I)< Silty sand. Light brown color. Fine to medium-grained. t--Damp. Loose. X A piece of plastic at 3.5 feet. SM 3 -ST-1 ,- -TOPSOIL {Os): I 21 98.9 -81 CL 4 -Silty clay. Medium to dark brown color. Sandy. Very moist to wet. Soft to moderately firm. Plastic. Contains -roots/ rootlets. At 4.5 feet, color changes to green-gray with brown I 17 107.2 -81 -5 -inclusions. ST-2 ,- v v OLD PARALIC DEPOSITS {Oop): 6 v CLJMJ v :·•:·.:·. Silty clay to clayey silt. Olive-green to brown color. -,- :·.-·: . Fine-grained. Damp. Firm to stiff. Highly weathered. . · : . SM/SF I 17 115.1 96 ST-3 - :0:-· . . ,, -Silty sand. Olive-green to brown color. Fine-grained. Damp. Dense. Slightly cemented. Fiable. ST-4 Bottom oftest pit at 7.0 feet. ■ BULK □ CHUNK T NUCLEAR GAUGE 'v GROUND FIGURE 4 SAMPLE DENSITY TEST WATER SMS Geotechnical Solutions, Inc. PROJECT: Proposed New Attached Building Test Pit: TP-3 CLIENT: Shane Garst PROJECT No.: GI-21-05-131 PROJECT LOCATION: 3357 Adams Street. Carlsbad Date Excavated: __ 5/_26_/2_1_ Logged By: __ ---=cC=.M=·-- Equipment: Mini Excavator (KUBOTA KX121-2). Remarks: No caving. Water seepage at 7.25 feet. u DEPTH ~g (ft) ;;i ...J 0 3 - MATERIAL DESCRIPTION ARTIFICIAL FILL (Uat): Silty sand. Brown color. Fine to medium-grained. Damp. Losse to medium dense. Contains roots/ rootlets, construction debris and 3/4 inches crushed rock. At 14 inches, encountered abandoned 9-inch diameter Terracotta pipe. The pipe was filled with soils. ST-1 TOPSOIL {Os): r/2 cJ ,,; ::i SM 94 Silty clay. Light gray-brown color. Sandy. Very moist to wet. Soft to moderately firm. I 20 105.9 CL --1--1-.-1---1--~ - At 3.5 feet, color changed to gray-green. 4 ~~v~\ ST-2 ~ 5 -f-WIMMI v OLD PARALIC DEPOSITS (Oop): Silty clay to clayey sand. Light yellow-brown color. Moderately weathered. Damp to moist. Moderately firm CUM I 18 103.9 90 77 v ~ to stiff. Mottled with light gray color. Contains ..... 1-i---2-3 ---t-I-04-.7-t---90--+-1-00---1 rust-colored staining. 6 ..YYYVJ 'YYYJt v v v From 5.5 feet, becomes very moist to wet. ST-3 ~ l'!<.14<.14¥./-------------------------1,-•.·•·· ·,.:·, . 7 ....... : '.:-.' " Silty sandstone. Olive-green to brown color. Fine to ■ BULK SAMPLE medium-grained. Moist to very moist. Medium dense. At 7 feet, becomes very moist. Cemented. Perched water seepage observed at the bottom of trench ST-4 □ Bottom of test pit at 7.3 feet. CHUNK DENSITY W NUCLEAR GAUGE n GROUND T TEST V WATER SM/SI ~ _ _.__ _ _.__ _ _.__ _ _,._ _ _,.__ ..... FIGURE 5 Pertinent Geologic Deposit GEOLOGIC MAP 3357 Adams Street Carlsbad, California I Oop2-4 I Old Paralic Deposits (Late to Middle Pleistocene) ,-___. 50 North~ Scale 1 :50,000 Excerpt From the Geologic Map of the San Diego 30' x 60' Quadrangle, California Michael P. Kennedy and Siang S. Tan, 2007. Figure 6 SMS Project: GI-21-05-131 GEOLOGIC CROSS-SECTION A-A' Legend 3357 ADAMS STREET, CARLSBAD, CA SCALE: l" = 10' A 130 125 120 115 O' 10' Existing Ground Surface Proposed Concrete Deck .-----, I I I I L ____ -.J D ---...................... LJ Proposed Deck Proposed Addition -----?-.. Geologic Existing Building Contact (Approx.) Proposed Building ~ Artificial Fill Existing Grade EE] Topsoil . . Test Pit Location ,._.Q~~ ·.1 Old Paralic Approximated Deposits A' Existing Stem Wall Existing Building --?---- 110 Proposed New Wall n '\ I :::,. I "" .... 1---T-i:=::===;~~ I ; Jl ............ ---:-..-?-_--\);\)-_,_ _ ;,.,tif,ci>I f;:' _S-_ -1-. -----_, _.:_ -,--.-----------?--- Existing Concrete Slab (To Be Re.moved) .... .... .... 105 100 ----------------------..,.J-1...-.--------_.!.-~-1-~ -- --L__J --' . ---~ -,--.-.,--~ -TopsoJ.HQs)~ ~ L--~ -. . -r----__ ? __ .:..--____ TP-2 .... ----•- TP-1 Old Paralic Deposits (Qop) 95 __._ _________________ __,;_ __ ......,_ __ ....;.... ____________________ __J SMS GEOTECHNICAL SOLUTIONS INC 5931 Sea Lion Place, Suite I 09 Carlsbad, CA 92010 NOTE: For Geotechnical Presentation Only Project Number: GI-21-05-131 Figure Number: 7 GEOLOGIC CROSS-SECTION B-B' L.!!15..end 3357 ADAMS STREET, CARLSBAD, CA SCALE: 1" = 10' O' 10' B 130 125 120 115 Proposed Carport Proposed Deck Proposed Addition Existing Concrete Slab (To Be Re.moved) -----, -Geologic : : Existing Building --· ·?-• Contact (Approx.) L ____ ....J D ~ Artificial Fill Proposed Building ~ -. -. -. -. Existing Grade EB Topsoil LJ Test Pit_Location ~ Old Paralic Approxunated ~ Deposits Proposed Deck Existing Ground Surface B' 110 105 § _ ----•----------- -----~ ---,---~? = ·• c_J:o~~(Q82_ _,______ . . . . . Artificifil Fill ~af) -,-~~-l--J~ ___ L ____ _ ?-----,----_ _:__=. ?_.:._==- TP-1 100 95 SMS GEOTECHNICAL SOLUTIONS INC 593 I Sea Lion Place, Suite I 09 Carlsbad, CA 92010 TP-3 TP-2 Old Paralic Deposits (Qop) NOTE: For Geotechnical Presentation Only Project Number: GI-21-05-131 Figure Number: 8 REGIONAL FAULT MAP SAN DIEGO COUNTY REGION ,_, '•~ . md.:ile -. ..., Holocene fault d1spldcement (during past 11.700 yt;:us) wrthou1 historic record. ------··-Lale Ouatema,y faun displacement {during past 700,000 years). -----····~-..a. Qu,Hemery faull (age undifferentiated) Pte-Quatemary faull (older thc1t 1 S miDlon years) or faull without recognized Quaternary d1i,plac:ement ADDITIONAL FAULT SYMBOLS -'--Bar and ball on do...mlt,rown side (relative or appsrent) Arrows alollg fault indicate relative oc apparent direction of lateral movement. ___L__ _ --.••.••. i,. Alrow on faul1 indieates direction of dip. low angle fault (barbs on upper plate). SMS GEOTECHNICAL SOLUTIONS INC 5931 Sea Lion Place, Suite I 09 Carlsbad, CA 920 I 0 l•;l exic.:ili .. Map is reproduced from California Geological Survey, "Fault Activity Map of California (201 0)". Project Number: GI-21-05-131 Figure Number: 9 SMS Geotechnical Solutions, Inc. 5931 Sea lion place, Suite 109 Carlsbad, CA 92010 Project Supervising Lab Tech Supervising Lab Manager N \!) rl JOO 90 80 70 l:l!) 60 C Vl V, ro a. ~o ...., C (1.) u .... 40 (1.) a. 30 20 10 0 500 Cobbles 100 TP-1@ 2' D60 D30 Dl0 ('() Location Depth Symbol TP-1 2' • TP-1 5' ~ Shane Garst S.S. S.M.S. N ----s:t = 00 ,--t ~-!'j,--t ~ ....... rt'. ,--t m Sieve Analysis ASTM D 6913 -04 0 <q' ..-I # # Job# Address Date 0 N # 0 m # Gl-21-05-131 3357 Adams Street, Carlsbad 6/9/2021 Tech Shawn Bahramian 0 0 0 0 0 <q' ..-I N # # # so 10 s 1 0.5 0.1 0.05 0.01 Grain Size (mm) Gravel Sand Coarse I Fine Coarse I Medium I Fine Silt or Clay TP-1@ 6.5' D60 D60 D60 D30 D30 D30 Dl0 Dl0 DlO uses NAT,w ¾ LL PL Pl Cu (D60/D10) Cc(D2 30/D60*D10) SM 6 SM-SP 11 I FIGURE 101 Notes: Typical Over-Excavation And Recompaction Detail Schematic, No-Scale FtNISI-IG~-----, SEE ~TE:I ------, UNEOFOENSE NATM 1'1ATEIU4L euILOIN6 FGUIOATlON MJN. fll=CCl"PACTEO Fill PEit SOILS ~T. &EE ALSO NOTE: '2 1. Minimum depth of over-excavation per soils report, but not less than 2' below the bottom of deepest footing(s) or depth of approved dense native ground, whichever greater. 2. New fills shall be compacted to minimum 90% compaction level per ASTM D1557 at approximately 2% above the optimum moisture content, unless otherwise specified in the soils report or directed in the field. Notes: Typical Foundation Formwork Detail AFTER SET CLEAN TO IIE'IO\'E LAITANCE OSCIJ"! EXCAVATION MIJST 6£ KEPT CLEAN AHO ~E Of-0EBIU9 Schematic, No-Scale --- 1. Foundation concrete shall be poured directly against neat trench excavation exposing approved bearing soil strata. 2. Foundation trench walls shall be stable. Sloughing or disturbed trench side walls shall not be allowed. 3. Foundation trenches shall be observed and approved by the project geotechnical consultant to insure clean excavation immediately prior to, and during placing of concrete. 4. Formwork is not permitted below grade unless fully formed. 5. Stakes are not permitted within the footing section. Project No: Gl-21-05-1 31 6 116GEOTECHNICAL SOLUTIONS, INC. 5931 Sea Lion Place, Suite 109 Carlsbad, California 92010 Figure: 11 (N) BUILDING ADDITION 1 (E) BUILDING CN) 4.5• Thk. Slab W/ 13 bars @ 15• C.C. Both WaY5 1-15 Cont. \ lin.f4 DWLs O 18~ CC Max-Drill 519• Hole Into (E) Ft11. Thorouuhh, Clean & EPOXY Grouti, (b,p.) _______ , • •' . · .. Min. ~Q:..Mil Sf~90. Moi~ Barri~; Mid-Ht. '1n Si~d'tbi: ··~· ,. "~ .-. Q, ,,r? d.-" • . ~ ~ -s, . • -~ ·--., I . ~ . ' : 0 GP..· . i) • • •• ,, ........ ;~~.:;:: I I---(E) Ft11. '"" d(bPf. -. mm~• "[ . v , '/' .1. ? ' •. Min. 90~ Comp'd Fill (typ.) .,.· •. •·· , ·.--~t't,4~---(N) 15"W bi,18• D Ftv. W/ Min. 2-1-'T & B (Also See Rpt.) ' Also See Rs>t. For R~medial Grading Re~~eh • _ · ._ •~· 1 · ."' \ ;; 5• MIN. •.·o l ,o .,. .I-0,111·.- ~'-··:· c>/ c)J~ Pro'd BTM of Over-J.. (typ) Te11D. Eun. Slape---~ ProjectNo: Gl-21-05-131 / Stabilization Geogrid (If Necessary) TYPICAL NEW ADJACENT TO EXISTING FOUNDATION DETAIL CONCEPTUAL & SCHEMATIC ONLY NO-SCALE SIISGEOTECHNICAL SOLUTIONS, INC. Figure: 12 Typical Retaining Wall Back Drainage Schematic, No-Scale GROUND SURFACE FILTER MATERJAL, 3/◄' · li' CRUSHED ROCKS (WRAPPED IN FILTER FABRIC OR CAL TRANS CLASS 2 PERMEABLE MATERIALS (SEE SPECIFICATIONS) WATERPROOFING (TYP) FINISH GRADE APPROVED FILTER FABRJC (MIIWI 1-40N) 12' OVcRI.AP, TYP. II .-s=P=EC ... IF-,CA~Tl-:::O-:-:N5:."'.F:-::O:":'R-:::CAl.~TRA'.".":"::NS:; ClASS 2 PERMEABLE MATERIAL (68-1 .025) U.S. STANDARD SIEVE SIZE 1. 3/4 3/B No. 4 No. 8 No. 30 No. SO No. 200 100 90-100 <10-100 25--40 18-33 5-15 0-7 0-3 SAND EQUIVALENT > 75 6" MIN. CONCRETE-LINED DRAINAGE DITCH FILTER MATERIAL., 3W · If CRUSHED ROCKS (WRAPPED IN FILTER FABRIC OR CAI.TRANS CLASS 2 PERMEABLE MATERIALS (SEE SPECIFICATIONS) WATERPROOFING (TYP) --- PROPOSED GRADE 6'MIN. 4' F'IIC PERFORATED PIPE MIN. (SCH ◄O OR SDR.35) MIN. 1 /2% FALL TO APPROVED OUTLET (SEE REPORT) NATURAi. OR GRADED SLOPE TEMPORARY 1 : 1 CUT SLOPE PROPERLY COMPACTED (MIN. 90%) BACKFILLED GROUND "'----BENCH AND TIGHTLY KEY INTO TEMPORAAY BACKCUT I,!, 8ACl<FILUNG PROGRESSES APPROVED FILTER FABRIC (MIRAFI 140N) 12' OVERLAP, TYP. CONSTRUCTION SPECIFICATIONS: .,__ _____ ◄'PVC.PERFORATED PIPE MIN. (SCH ◄0 OR SDR35) MIN. 1 /2% FALL TO APPROVED OUTlET (SEE REPORT) 1. Provide granular, non-expansive backfill soil in 1 :1 gradient wedge behind wall. Compact backfill to minimum 90% of laboratory standard. 2. Backdrain should consist of 4" diameter PVC pipe (Schedule 40 or equivalent) with perforations down. Drain to suitable at minimum½%. Provide¾" -1-½" crushed rocks filter materials wrapped in fabric (Mirafi 140N or equivalent). Delete filter fabric wrap if Caltrans Class 2 permeable material is used. Compact Class 2 permeable material to minimum 90% of laboratory standard. · 3. Seal back of wall with approved waterproofing in accordance with architect's specifications. 4. Provide positive drainage to disallow ponding of water above wall. Drainage to flow away from wall at minimum 2%. Provide concrete-lined drainage ditch for slope toe retaining walls. 5. Use 1-½ cubic feet per foot with granular backfill soil and 4 cubic feet per foot if expansive backfill is used. Project No: Gl-21 -05-131 6J/6GEOTECHNICAL SOLUTIONS, JNC. 5931 Sea Lion Place, Suite 109 Carlsbad, California 92010 Figure: 13 NOTES: (a) RE-ENTRANT CORNER REINFORCEMENT NO. 3 BARS PLACED MID-HEIGHT IN SLAB (b) ISOLATION JOINTS CONTRACTION JOINTS (c) ~ RE-ENTRANT CORNER CRACK I NO SCALE l 1. Isolation joints around the columns should be either circular as shown in (a) or diamond shaped as shown in (b). If no isolation joints are used around columns, or if the corners of the isolation joints do not meet the contraction joints, radial cracking as shown in (c) may occur (reference ACI}. 2. In order to control cracking at the re-entrant corners(+/ -270 degree corners), provide reinforcement as shown in (c). 3. Re-entrant corner reinforcement shown herein is provided as a general guideline only and is subject to verification and changes by the project architect and I or structural engineer based upon slab geometry, location, and other engineering and construction factors. TYPICAL ISOLATION JOINTS AND SMS GEOTECHNICAL SOLUTIONS, INC. RE-ENTRANT CORNER Consulting Geotechnical Engineers & Geologists REINFORCEMENT 5931 Sea Lion Place, Suite 109 Carlsbad, California 92010 PROJECT NO. FIGURE NO. 760-602-7815 smsgeosol.inc@gmail.com Gl -21-05-131 14 Typical Pipes Through or Trench Adjacent to Foundations SPREADFTG., CONT. FTG., OR ~BWJ Schematic, No-Scale LOCATE TRENCH SO --~ THAT FOOTINGS.ARE NOT UNDERMINED 1·-s• MIN BACKFILL TRENCH PER G£0TECHN1CAL REPORT NOTES: 1. 00 NOT PlACE SLEEVES OR CONOUIT IN ISWTEO SPREAD FOOTJ>-'GS -RUN AROUND OR 6£l.O'IJ n£S£ FOOTINGS. 2. SLEEVES ARE NOT TO PASS ..... THROUGH CONTINUOUS FOOTtNGS n" . 2 >: NOEXCAVA~toN~ ___/' ''-. OR GRADE B£AMS UM.ESS SHOWN OTKERWfSE -WHERE SlEEVES ARE PERMITTED, SEE SEE SECTION eaow ea.ow THIS LINE SLABON GAA.Of Trench Adjacent to Foundation CONT. FOOTNG ORGRA0£8£At1 ~ • : • jl> • ~ 4 •. "' • • ~ •• . . . . . . .. . . . A SEE r-JOTE 2 PR0\11~ PiPE SU.EVE 1I.D. 'l' 1.ARGBl THAN P1JiE 0.0.) WHERE ADJACENT TO c<mc .• lYPlCAl LNIT OIST~E BElWEEN Sl.EEVES TO NO LESS THAM LARGER SlEE\IE OUTSIDE DIAMETER OR 6" ELEVATION A-A COO. FOOTWG OR~~ . . . ~ 0 i:=~=j~~~:~~~~t~~~:~~[:I . . . !=? ..__ __ EXTEND FOOTING MIN. 6" BELOW SLEEVE (TYP.) A P Project No: Gl -21 -05-131 Pipes Through or Below Foundation SJ/SGEOTECHNJCAL SOLUTIONS, INC. 5931 Sea Lion Place, Suite 109 Carlsbad, Califor nia 92010 • .r:,. 't> • ~ ,. . . Figure: 15 APPENDIX ASCE. AMERICAN SOCIETY Of CM. ENGINEERS Address: No Address at This Location https ://a see 7hazardtool .online/ ASCE 7 Hazards Report Standard: ASCE/SEI 7-16 Risk Category: II Soil Class: D -Stiff Soil Page 1 of 3 Elevation: 109.44 ft (NAVO 88) Latitude: 33.1604 Longitude: -117.3377 •'.•r{_J:l5idt .;,.,tad \ \ \ a .... 1 .'i:11 ,·0•..: 'It Mon May 24 2021 ASCE. AMERICAN SOCIETY Of CM. ENGINEBIS Seismic Site Soil Class: Results: Ss : S1 Fa : Fv : SMs Sr.11 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 0.758 Cv : 1.311 Ground motion hazard analysis may be required. See ASCE/SEI 7-16 Section 11.4.8. Data Accessed: Mon May 24 2021 Date Source: USGS Seismic Design Maps https://asce 7hazardtool.online/ Page 2 of 3 Mon May 24 2021 ASCE. AMERICAN SOCIETY OF CML ENGINEERS The ASCE 7 Hazard Tool ls 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 Mon May 24 2021