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4726 Fairway Bl Soils Report Update For Proposed Custom HomeGEOTECHNICAL INTERNATIONAL Topographic Survey & Civil. Structural. Geotechnical, Engineering 13139 Harbor Boulevard, Garden Grove, CA 92843 Tel (949)302-2901& (949) 8305440, E-mail: cachnguyen@ymail.com Project No.G1310181 November 26, 2013 Hong Wang Fairway Development, Inc. 162 California Street, Suite A Arcadia, CA 91006 Subject: Preliminary Geotechnical Investigation for Proposed One -Story Single Family Home at 4726 Fairway Boulevard, Lot 4, Block K, Tract 2567, City of Chino Hills, California Dear Hong Wang: In accordance with your authorization, GEOTECHNICAL INTERNATIONAL has performed a preliminary geotechnical investigation of NEW ONE STORY SINGLE HOME project located at 4726 Fairway Blvd., Lot 4, Block K, Tract 2567, City of Chino Hills, California. The purpose of our investigation was to assess the existing geotechnical conditions at the site in order to provide geotechnical input for site preparation, foundation design, and construction of the proposed new single family home residence. Our investigation generally consisted of background research and review of previous data pertinent to the site, site reconnaissance for evaluation of existing surface site conditions, and engineering analysis to provide geotechnical recommendations for foundation design site preparation This report summarizes our finding and provides our conclusions and recommendation. Page 1 Site Description and Proposed Development The subject site is located on the north side of Fairway Boulevard, east of Yorba Avenue, west of Pheasant Avenue within a fully developed residential area. He lot is bounded on the three sides by existing one story house. A wooden fence and block wall 4-6' high exists along the property lines on the three sides. The site is a relatively flat area. No distress was noticed or reported to the existing structures. The existing driveway will be removed and replaced by new driveway approach (W=14', X=3'), existing power pole will be protected in place and a new one-story house with attached two -car garage will be constructed at the site. Major grading (raw cut/ raw fill) is not proposed. Geotechnical Conditions Three (3) test holes were excavated to depth of approximately 3 feet using a hand - operated tool. The approximate location of our test hole is depicted on the attached Site Plan. The geotechnical log of the test hole is included in Appendix B. As the test holes were advanced, relatively undisturbed soil samples were obtained at the selected depth intervals using a tube sampler. The sampler was driven into the undisturbed earth materials using a steel hammer. Approximate sample depths are noted on the log Bulk samples of near surface earth materials were secured from the cutting. Upon completion of sampling, the test holes were backfilled with on -site earth materials Laboratory testing consisting of expansion index and Atterberg Limits was performed on a near -ground surface sample. The laboratory test results are included in Appendix C. Based on the published geologic map prepared by the California Division of Mines and Geology (CDMG), the site is underlain by alluvium [ map symbol Qai ]. Based on the data of our test hole, field observation, and laboratory testing, the on -site, the near ground surface on site earth material generally consists of dark brown stiff to very stiff very fine sandy clayey silt/silty clay having a medium expansion potential (with expansion index of 590 and a plasticity index of 19 (Liquid Limit of 47 and Plastic Limit of 28). The effective plasticity index of 20 of 20 can be used. Proposed Development We understand that a new one story single family residence with 2 attached two car garage will be built at the Faulting and Seismicity The subject site is located within Seismic Zone Factor 4, in Southern California, which is a major earthquake -prone region. Therefore, the current and future property owners of this property should be aware of the seismic risks associated with being in this zone. No active faults are known to exist within or near the site. Therefore, the probability of primary surface rupture or deformation at the site is considered very low. Page 2 The site is not designated to be located within the Special Studies/Earthquake Zone under the Alquist-Priolo Special Studies Act. For conservative purposes, the Site Class B should be used for the soil properties at the subject site. The procedure outlined in the 2011 California Building Code, Section 1613 — Earthquake Loads and any other sections, as determined by the civil/structural design engineer should be used for structural design. The following seismic parameters should be used for the subject site which has the latitude of 33.97219 and longitude of-117.70166. • Site Coefficients: Fa = 1.0 F, = 1.0 • Mapped Spectral Accelerations Values: SS = 1.932 (for the short period of 0.2 second) SI = 0.689 (for the 1-second period) • Maximum Considered Earthquake Spectral Response Accelerations: SMS = FaS, = 1.932 (for the short period of 0.2 second) SMI = FvS1 = 0.689 (for the 1-second period) • Design Spectral Response Accelerations: SD, = 2/3 SMS = 1.288 (for the short period of 0.2 second) SDI = 2/3 SMI = 0.459 (for the 1-second period) The Seismic Design Category B can be used for the site. The Civil/Structural Design Engineer should consult with the project geotechnical consultant, if additional geotechnical information is needed for structural design. Liquefaction Potential Based on the SEISMIC HAZARD ZONES MAP, prepared by CDMG (which cover the subject site) the subject property is located within a potential liquefaction zone. Therefore, the subject site can be considered subject to liquefaction. Therefore, the property owner should be aware of the risk associated with the potential differential settlement caused by the potential liquefaction For conservative purposes, the highest potential settlements due to liquefaction of the site for total and for differential should be used for subject site. Also, to withstand potential loss of soil support due potential differential settlement, a relatively heavy reinforced footings and slabs together with grade beams are recommended for the proposed addition as outline in the BUILDING FOUDATION DESIGN GUIDELINES of this report. The subject lot and other lots located within this area are situated on a very broad flat alluvium region far away from the ocean. The on -site subgrade earth materials generally consisted of very fine silty sand /sandy silt can be considered non -plasticity. A slope conditions or drainage or stream channel does not exist at the site; therefore, lateral spreads, oscillation, surface manifestation, and loss of bearing capacity, etc. are not anticipated to be credible hazards for the proposed 2-story home. Page 3 However, it should be recognized that structural mitigation may not reduce potential of the soils is liquefy during an earthquake; and there will remain some risks that he structure could still suffer damage if liquefaction occur during a very strong earthquake. Slope Stability The site is a flat area; therefore, slope instability is not a concern for the proposed development. Ground Water Ground water did not encounter in our 5 ft deep test hole. Deep excavations and deep footings are not proposed. Therefore, ground water is not anticipated to be a problem for the proposed development. CONCLUSIONS AND RECOMMENDATIONS General Conclusions Construction of the proposed new house at the subject site is considered geotechnical feasible, provided the recommendations outlined in this report are implemented. Note: The conclusions and recommendations of this report are based on information as interpreted from our limited subsurface investigation. It is not anticipated but they should be revised accordingly if geotechnical conditions to be exposed during site preparation/ grading and construction significantly differ from our findings and interpretations. Conventional shallow footings with slabs -on -grade can be used for support of the proposed new house. The following recommendations are considered minimum and may be superseded by more restrictive requirements of the architect, civil/structural design engineer, building codes, or governing agencies. Geotechnical Impact on Neij4hborins4 Properties It is the opinion of the undersigned, based upon our work as outlined in this report, that if performed in accordance with our recommendations and properly maintained, (1) the proposed grading and building will be safe against hazard from future landslide, settlement, or slippage, and that (2) the proposed grading and building will have no adverse effect on the geologic stability of properties outside of the building site. Site Preparation/Grading To create relatively uniform subgrade areas for the proposed new house and other new "structural" objects including new exterior concrete slabs -on -grade, if any, the upper 1+ ft thick near ground surface earth materials should be over -excavated and recompacted. The over -excavation and recompaction should be extended laterally outside/beyond the Page 4 perimeter of the new structures/ slabs a minimum distance equal to depth of removal (1 + ft. in this case). No deeper remedial removal is anticipated; however, if deeper loose/soft soils are encountered, such as due to removal tree roots or other underground objects such as existing footings, pipes etc., deeper remedial removal and re -compaction will be required. This will be determined in the field by the project geotechnical engineer, based on the actual conditions exposed at the time of site grading. The clean on -site earth materials without vegetation and roots can be reused as fill/backfill materials. Fill and backfill materials should be free of organic matter and oversized materials, 6 inches or greater in diameter, placed in near -horizontal loose lifts not to exceed six inches in thickness, and moisture conditioned to slightly over optimum moisture content prior to compaction. Thicker lifts can be used if capable of being properly compacted to the required relative compaction (such as by using heavy compaction equipment). Imported soils, if any, should also be free of organic matter and oversized rocks, 6 inches or greater in diameter, and should have a very low expansion potential. Imported soils should be observed/tested and accepted by the geotechnical consultant prior to using at the site. In general, grading at the site should be performed in accordance with the requirements of the City of Chino Hills and under the geotechnical observation and testing of the project geotechnical consultant. The compaction criterion for fill and backfill materials is a minimum of 90% of the maximum density determined in accordance with ASTM Test Method D1557. BUILDING FOUNDATION DESIGN GUIDELINES Allowable Foundation And Lateral Pressures For conservative purposes, the allowable foundation pressure of 1,500 psf, lateral bearing of 100 psf/ft., and coefficient of friction of 0.2 can be used for the site. Footings Footings should be embedded minimum 18 inches into approved competent materials. Exterior footing will be 12"x 24" with 2#4 at top and at bottom. Interior footing will be 12"x 18" with 2 # 4 at top and at bottom. Minimum widths for isolated column/pad footings should be 24-inches, and continuous wall footings should be 18-inches for one-story. Where located adjacent to a utility trench, footings should be extended to have the footing bottom located below a one-to- one imaginary plane projected from the inside bottom edge of the trench. Minimum footing reinforcement should be two 44 re -bars at top and two #4 re -bars at bottom. Page 5 Slabs -on -Grade Slabs -on -grade should be 4 inches thick, reinforced with #3 rebars at 24 inches on centers, or equivalent, place at mid -height of the slab. Slabs should be underlain by 2-inch thick layer of clean sand. For moisture sensitive floor areas, the slabs should also be underlain by a 6-mil polyethylene moisture barrier (such as Visqueen) to be placed above the subgrade soils and below the 2-inch thick clean sand layer. The moisture barrier should be properly lapped and sealed at joints and around any breaks such as openings for utility conduits. Slab Subarade Pre -Saturation Slab subgrade earth materials are anticipated to have a very low expansion potential. Therefore, pre -saturation is not considered necessary. The slab subgrade earth materials should be thoroughly sprinkled with water, as much as possible, prior to concrete pour/placement of moisture barrier membrane. Other Recommendations for Reducing Slab Crackina While not a geotechnical issue, the potential for slab cracking may also be reduced by careful control of water/cement ratio and slump of concrete. The contractor should take appropriate curing precautions during the pouring of concrete in hot weather to reduce cracking of slabs. A slip sheet (or equivalent) can be utilized if grouted tile, marble tile, or other crack - sensitive floor covering is planned to be replaced directly on concrete slabs. Settlement The conventional total settlement of 1 inch and a differential settlement of '/2 inch over a horizontal distance of 40 feet which are considered tolerable for residential buildings are anticipated and would occur during the construction stage. Site Drainaae In general, the site should be graded to ensure surface water flows away from all improvement structures and into a drainage system for proper discharge. We recommend the use of area drains with sufficient inlet grates to facilitate surface drainage. Roof gutters should be provided and downspouts should be directly connected to the surface drainage system for proper discharge. Roof drains, gutters and downspouts should be maintained to function as intended. Outlet drains should be kept open. Irrigation at the site, if any, should be kept to a minimum required to support plant life. Water should not be allowed to pond anywhere at the site. The 2010 CBC requires should be followed, as needed. Page 6 Seismic Design We recommend new structures be designed to meet the current building codes and requirements of the governing agencies. The civil/structural design engineer should consult with the project geotechnical consultant, if additional geotechnical information is needed for the seismic design. Cement Tvne For Concrete in Contact with On -Site Earth Materials Sulfate attack was not observed for the existing on -site building and other buildings in the vicinity. It appears sulfate attack on concrete is not a problem for the City of Arcadia. Therefore, Type V cement with a maximum water/cement ratio of 0.45, and a minimum concrete strength, f � of 4,500 psi is not considered necessary. Concrete strength designed by the civil/structural design engineer such as 2,500 psi can be used. Other requirements by governing agencies, if any, should be followed. Additional sulfate content testing can be performed for the finished subgrade soils during or after completion of the precise grading but prior to concrete pour, as needed. Corrosion To Ferrous Metals and Conner For conservative purposes, the on -site soils can be considered severely corrosive to ferrous metals and copper. Therefore, if underground/buried ferrous metals or copper are planned to be used at the site, they should be properly protected. A corrosion specialist can be consulted. Testing can be performed for verification of the potential corrosion of the on -site soils to ferrous metals and copper, if needed. The test can be performed during and/or after completion grading. Geotechnical Review of Foundation Plans If required by the City, we will geotechnically review the foundation plans, including details/specifications and any other design drawings and structural calculations, if any, related to geotechnical data prior to construction. The purpose of this 2eotechnical review is to verify that the recommendations contained in this report have been properly interpreted and are incorporated into the design. Geotechnical Observation and Testing During Construction We recommend that a qualified geotechnical consultant be . retained to provide geotechnical engineering services, including geotechnical observation/testing, during the construction phase of the project. This is to verify the compliance with the design, specifications and/or recommendations, and to allow design changes in the event that subsurface conditions differ from those anticipated. Page 7 Geotechnical observation/testing can be performed at the following stages: ■ During ANY grading operations, including excavation, removal, filling and backfilling, etc. ■ After excavation for building footings to verify the adequacy of underlying materials. ■ After pre -saturation of slab subgrade earth materials, if any, prior to pouring concrete. ■ During backfill of drainage and utility line trenches, if any, to verify proper compaction. ■ When/If any unusual geotechnical conditions are encountered. Note: If Geotechnical International is not provided the opportunity to perform the izeotechnical observation/testing during the construction phase, Geotechnical International will take no responsibility for the conclusions and recommendations contained in our report in the event that subsurface conditions differ from those interpreted and anticipated during our preliminary investigation phase prior to the start of construction. Page 8 CLOSURE The conclusion and recommendations contained in this report are presented based on geotechnical data as described herein which are believed representative of the total project area. However, earth materials can vary in characteristics, both laterally and vertically, and those variations could affect the conclusions and recommendations contained herein. As such, observation and testing by a qualified geotechnical consultant during the construction phase of the project are essential to confirming the basis of this report. This report has been prepared consistent with that level of care being provided by other professionals providing similar services at the locale and time period. The contents of this report are professional opinions and as such, are not to be considered a guaranty or warranty. This report should be reviewed and updated after a period of one year or if the property ownership, site conditions or proposed development change from that described herein. The following are attached and complete our report: Appendix A — References Appendix B — Geotechnical Log of Test Hole Appendix C — Laboratory Test Results Figure 1 — Vicinity Map Figure 2 — Site Plan/Geotechnical Map Figure 3 — General Topographic Map Figure 4 — Published Geologic Map Figure 5 — Fault Zone Map If you have any questions or require clarification, please contact this office. This opportunity to be of service is sincerely appreciated. Very truly yours, Cach Q. Nguyen, P.E. Registered Civil Engineer RCE 57504, Expires 12-31-2013 Page 9 APPENDIX A REFERENCES Page 10 REFERENCES General 1. California Division of Mines and Geology, The Resource agency, Department of Conversation, 1965, 1985, "Geologic Map of California, San Ana Sheet", Olaf P.Jenkins Edition, Compilation by Thomas H. Rogers, Scale 1:250,000 (1" = 4 miles), dated 1965, fifth printing 1985. 2. California Division of Mines and Geology, Department of Conversation, 1998 (Published by International Conference of Building Officials), "Maps of Known Active Fault Near Source Zones in California and Adjacen Portions of Nevada", Scale I/4" = 1 km, dated 1998. California Building Code (CBC)2001/Uniform Building Code (UBC), 1997, volume 2, Structural Engineering Design Provisions, Seismic Zone Map of the United States, Figure 16-2 and Table 19-A-4, 16-I, 16-J, 16-Q, 16-R, 16-5, 16-T, and 16-V, dated 1997. 4. U.S.G.S., United States Department of Interior, Geological Survey, 1965, 1981, "Topographic Map, Prado Dam Quadrangle, California.", 7.5 Minute Series, Scale 1:24,000 (1" = 2,000 ft. or 1" = 0.38 Mile), dated 1967, photorevised 1981. 5. California Division of Mines and Geology, The Resource Agency, Department of Conservation, 2001, "SEISMIC HAZARD ZONES, PRADO DAM QUADRANGLE," scale 1:24,000 (1"2,000 ft.) (1"=0.38 Mile), Released January 17, 2001. Page 11 APPENDIX B GEOTECHNICAL LOG OF TEST HOLE Page 12 Pro j ec , Joe Wijono Project Number: G070104 Hand Tools Equipment: GEOLOGIC 01-26-07 AT-FITUDES I DATE: i GRAPHIC REPRESENTATION i o o a Logged by; LNP Elevation: Location: DESCRIPTION: Brass roots: 0 — 6 f" Dark brown very fine sandy clayey silt / silty clay, stiff to very stiff, moisture, for upper 1 foot. More moisture and more clayey with depth, uniform Total Depth = 3 ±' No Caving — No free standing ground water. Hole back filled with on -site soils TRENCH NO. TH-1 GEOLOGIC UNIT Qal SCALE: 1" _ �� SURFACE SLOPE: TREND: ENGINEERING PROPE, S w o : o cn z .-• n p co C ^ rD SEE 13.6 82.3 c C C Pro j eC c : .b�$s s6 6�4naki➢ Logged by: LNP Project Number: G070104 Elevation: Equipment: Location: GEOLOGIC 01-26-07 DESCRIPTION: ATTITUDES DATE' Brass roots: 0 — 6" Dark brown clayey silt / silty clay, with trace of very very fine sand, stiff and moist. More moisture with depth below 1 foot f, more clayey, very uniform Total Depth = 3f' No Caving — No free standing ground water. Hole back filled with on -site soils ENGINEERING PROPL ES TRENCH iJo. TH-3 c co x w o v cn z B -• •- n GEOLOGIC M Cn UNIT eD O Qal 04 ED19.8 88.7 GRAPHIC REPRESENTATION SCALE: 1" = SURFACE SLOPE: TREND: 7 e e a —�— e e e e •J� --1 1 1 1 —1 1 1 e 1 e 1 � 1 1 1 1 �'i - c Projec. Joe Wijono Logged by: LN' Project Number'; G070104 Elevation: Equipment: Hand Tools Location: GEOLOGIC A-FFITUDES DATE: DESCRIPTION: Brass roots: 0 — 6 Dark brown clayey silt / silty clay, with very minor very fine sand, moisture, stiff. More moisture below 1 foot, more clayey Total Depth = 3' No Caving — No free standing ground water. Hole back filled with on -site soils ENGINEERING PROPEL E5 TRENCH No. TH-2 N w M o ^ o a (o .- • n :I� GEOLOGIC G ^ UNIT cn CD Qal ►� [D 21.2 90.1 U Q 3r GRAPHIC REPREaENTATION SCALE: 111 = SURFACE SLOPE: TREND: C APPENDIX C LABORATORY TEST RESULTS Page 13 IN -PLACE DENSITY AND FIELD MOISTURE CONTENT TEST RESULTS Samnle Location Moisture Content (%) Dry Densitv (ncf) TP-1 @ 1' 13.6 82.3 TP-2 @ 3' 21.2 90.1 TP-3 @ 2' 19.8 88.7 Page 14 EXPANSION INDEX TEST RESULTS Sample Compacted Moisture Content Expansion Expansion . Location Dry Compacted Final Index Potential Densitv (pcfl (%) (%) Classification TP-2 @ 0-2' 94.5 14.5 27.4 59 medium Test Method: ASTM D4829 (2001 CBC/1997 UBC Code Standard 18-2 and Table 18-I-B) Page 15 2�2�A o" Eb 9 'Y°3 a <9w � a 77,,�79a'l77a9 ®A_ n 9 9 00 Fa LJI 7l A NI 3bl 0 T C) R� d 4�9g 3N d 3nv vHOrvS5vtl AAVE a p� R YONTFA Y AYE to AYE F Y T AYE a � \� H MONTEI"S ;. r i \c S O �HsnoN3 r � j PEYTON DR ly R a a all ZRR p� 0 $ m AA OR � I• )OAVi9v � Am L o I/ 3AV VNOWVFi n x 2 m 0 'r m YORBA AVElw m Vy"2 eenNIE..WSTAALE NORTON AVE n�-Y- �Y-4 ! TELEPHONE AVE IERA 6 ITA JI CENTRAL .AVE � J. PaL'�['AAQAAAfAA[.A LAA6aAAA1'�AA(��f��®e0 _ 1 26' L 8.50' 49.50' L 6' L 15' L 20' 1 (617.54F.G.)' ' I N 00'29'00" W - 125' -PROPERTY LINE a 'I w W N 1a ti X i 18' 61( 7.QOT.C.) (617.18F.5.) 618.84F.G.) F.G.y )--�8.54T.G 7 i=1% d 8 81 50T.G. i=1% �� �=�1 3'PVC 00.005- I=1% Q 8 =o.az _616.841NV. 8� T 7 59T.G 616.76F.L. (624.40T.W.Lill g MIN. = 3•Pvc @a.00s� MIN. ? 7 0 G 618.94F.G. MIN. 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TU Ste AVENUEQ. 97—,. r-- N r tell i 1 e 625— w.;"ZagirM Station 0 ----------- ---------- 4j MERRI *VE, 627.OjuhinO 609- - %- atwage Disposal -'- 7 Trailer A, 7 b C3 r SITE N % n T 0 -71) 0 �\j L V U.S.G.S., United States Department of Interior, Geological Survey, 1965, 1981, "Topographic Map, Prado Dam Quadrangle, California.", 7.5 Minute' Series, Scale 1:24,000 (1" = 2,000 ft. or I" = 0.38 Mile), dated 1967, photorevised 1981. Ke— I E .G-EN- RAL TOPOGRAPHIC MAP, - FIGURE 3 f 0N A 4 M 1. a R V R 7 W V 001 \N ate r Q01 J, 'allfornia I stl'tuti or Men SITE A L U ND Q I? E S .1' 7\a I . ..... .. 566 A D, U-� W i nd ru o California Division of Mines and Geology, The Resource agency, Department of Conversation, 1965, 1985, "Geologic Map of California, San Ana SGENERALIZED GEOLOGIC Olaf P.Jenkins Edition, Compilation by Thomas H. Rogers, Scale 1:25U,UUU %W (P = 4 miles), dated 1965, fifth printing 1985. ;��FIGURE 4 . , co 6 ill :