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Home My WebLink AboutCT 04-01; YAMAMOTO PROPERTY; OBSERVATION & TESTING; 2012-03-27now ::i:rt :::e1 Environmental / Corporate Costa Mesa, California 92626 1: 714.549.8921 F: 714.549.1438 past + present + future it's in our science Engineers. Geologists Environmental Scientists March 27, 2012 J.N. 155-10 Grading Permit No.: GR1O-13 Mr. Tom Tupman WARMINGTON RESIDENTIAL CALIFORNIA 3090 Pullman Street Costa Mesa, CA 92626 Subject: Summary of Observation and Testing, Reconditioning of Lots 9, 10, 15 and 16 of Tract 04-01, The Poinisettia Ridge Project, Southeast Corner of Black Rail Road and Songbird Avenue, City of Carlsbad, San Diego County, California References: See Attached List. Mr. Tupman: Presented herein are the results of our field observation and testing performed during reconditioning of the pad surfaces on Lots 9, 10, 15 and 16 of Tract 04-01. The purpose of this most recent grading was to restore the subject pads back to their original condition as they existed at the completion of rough grading (Reference No. 1). A single-family residence is proposed on each lot. OBSERVATIONS AND TESTING A representative of this firm provided observation and testing during re-conditioning of the pad surfaces on the subject parcels and lots. In general, the work was performed in the following manner: 1. All construction debris and weeds were removed from each parcel and lot. The existing pad surfaces on each lot were scarified to depths of 4 to 6 inches, watered as necessary to achieve near optimum moisture conditions, and then recompacted in place to a minimum relative compaction of 90 percent by wheel-rolling with a skip loader and a water truck filled to capacity. 3. Field density tests were performed using Nuclear Test Method ASTM D 6938-08a. Test results are presented in Table I and approximate locations of the field density tests are shown on Plate 1. WARMINGTON RESIDENTIAL CALIFORNIA March 27, 2012 Lots 9, 10, 15 and 16 of Tract 04-01 J.N. 155-10 Page 2 Field density tests were taken at regular intervals to verify adequate compaction. Maximum dry density and optimum moisture content of representative samples of the on-site soils were determined in our laboratory in accordance with Test Method ASTM D 1557-07. The results of these laboratory tests are summarized in Table II. Visual classification of earth materials in the field was the basis for determining which of the maximum density values was applicable for a given density test. One-point checks were performed to supplement visual classifications. CONCLUSIONS Based on the results of our observations, on our field and laboratory tests, and on our experience and judgment, it is our opinion that the completed earthwork discussed herein has been performed in general accordance with our recommendations for processing of existing grades within the subject lots. Recompaction of the pad surfaces under the purview of this report has been completed under the observation of and with selective testing by Petra Geotechnical, Inc., and is found to be in compliance with the Grading Code of the City of Carlsbad, California. The completed work has been reviewed and is considered adequate for the construction now planned. Foundation design recommendations provided in Reference Nos. 3 and 4 remain applicable and no further recommendations are needed at this time. REPORT LIMITATIONS A representative of Petra Geotechnical, Inc. (Petra) was present on-site on an on-call basis during post-grading operations for the purpose of providing the owner's representative with professional opinions and recommendations. These opinions and recommendations were developed based on field observation and selective testing of the contractor's work. Our scope of services during this project did not include supervision or direction of the contractor, his personnel or his subcontractors. As documented in this report, our observations and testing did not reveal any obvious deviations from the recommendations provided in the referenced geotechnical reports by our firm; however, Petra does not in any way guarantee the contractor's work, nor do our services relieve the contractor (or any subcontractors) of their liability should any defects subsequently be discovered in their work product. Based on our findings, this report was prepared in conformance with generally accepted professional engineering practices, and no further warranty is implied nor made. WARMINGTON RESIDENTIAL CALIFORNIA March 27, 2012 Lots 9, 10, 15 and l6of Tract 04-01 J.N. 155-10 Page 3 This report is subject to review by the controlling authorities for the project. Should you have any questions, please do not hesitate to call. Respectfully submitted, PETRA GEOTECHNICAL, INC. Siamak JafroudjhD :;/Z7//L— Senior Principal Engineer GE 2024 SM/SJ/kg W:\2010\100\155-10 Warminglon Residential California (Black Rail)\300\recert lots 9,10,15, 16.doc WARMINGTON RESIDENTIAL CALIFORNIA March 27, 2012 Lots 9, 10, 15 and 16 of Tract 04-01 J.N. 155-10 Page 4 REFERENCES Christian Wheeler Engineering, Report of Field Observation and Relative Compaction Testing, Grading and Site Improvements, Black Rail 16-Lot Development, Black Rail Road and Songbird Ave., Carlsbad, California: prepared for Watkins Landmark Construction, dated January 4, 2007 (CWE 2050489.05). Geotechnical Commentary on Design and Construction of Post-Tensioned Slabs On-grade for Lots 1 through 16 Carlsbad Tract No. 04-01, The Poinsettia Ridge Project, Southeast Corner of Black Rail Road and Songbird Avenue, City of Carlsbad, San Diego County, California, letter by Petra Geotechnical, Inc., dated April 1, 2010. Geotechnical Review of Precise Grading Plans and Updated Foundation Design Recommendations, Lots 1 through 16 Carlsbad Tract No. 04-01, The Poinsettia Ridge Project, Southeast Corner of Black Rail Road and Songbird Avenue, City of Carlsbad, San Diego County, California, letter by Petra Geotechnical, Inc., dated April 13, 2010. Response to City of Carlsbad Review Sheet and Review of Precise Grading and Foundation Plans, Lots I through 16, Carsbad Tract No. 04-01, The Points ettia Ridge Project, Southeast Corner of Black Rail Road and Songbird Avenue, City of Carlsbad, San Diego County, California, letter by Petra Geotechnical, Inc., dated July 14, 2010. WARMINGTON RESIDENTIAL CALIFORNIA March 27, 2012 Lots 9, 10, 15 and 16 of Tract 04-01 J.N. 155-10 Page 5 TABLE I FWII) DVNSITV TPST SuMMARy Date of Test Test No. .. Parcel Number Depth *, (ft.) Moist. (%) Unit Wt. lbs./cu.ft. % Rd. Comp. Soil Type 3/26/2012 1 Lot #9 FG 12.6 116.0 92 A 3/26/2012 2 Lot#10 FG 13.3 115.1 91 A 3/26/2012 3 Lot# 15 FG 12.9 115.7 92 A 3/26/2012 4 Lot #16 FG 13.1 114.8 91 A ru - rinisn uraae * - Depth Below Finish Grade TABLE II Soil Type Optimum Moisture (%) Maximum Dry Density (pci) A - Silty Sand (SM) 10.0 126.0 Ora PETRA :::eonmw1ta1 / Corporate 3190 rt Loop Costa Mesa, California 92626 T: 714.549.8921 F: 714.549.1438 1 - past + present + futur. it's in our scienc. Engineers, Geologist Environmental Scientist May 10, 2011 J.N. 155-10 Grading Permit No.: GR1O-13 Mr. Tom Tupman WARMINGTON RESIDENTIAL CALIFORNIA 3090 Pullman Street Costa Mesa, CA 92626 Subject: Summary of Observation and Testing, Reconditioning of Lots 3 through 6 of Tract 04-01, The Poinisettia Ridge Project, Southeast Corner of Black Rail Road and Songbird Avenue, City of Carlsbad, San Diego County, California References: See Attached List. Mr. Tupman: Presented herein are the results of our field observation and testing performed during reconditioning of the pad surfaces on Lots 3 through 6 of Tract 04-01. The purpose of this most recent grading was to restore the subject pads back to their original condition as they existed at the completion of rough grading (Reference No. 1). A single-family residence is proposed on each lot. OBSERVATIONS AND TESTING A representative of this firm provided observation and testing during re-conditioning of the pad surfaces on the subject parcels and lots. In general, the work was performed in the following manner: 1. All construction debris and weeds were removed from each parcel and lot. The existing pad surfaces on each lot were scarified to depths of 4 to 6 inches, watered as necessary to achieve near optimum moisture conditions, and then recompacted in place to a minimum relative compaction of 90 percent by wheel-rolling with a skip loader and a water truck filled to capacity. Field density tests were performed using Nuclear Test Method ASTM D 6938-08a. Test results are presented in Table I and approximate locations of the field density tests are shown on Plate 1. WARMINGTON RESIDENTIAL CALIFORNIA May 10, 2011 Lots 3 through 6 of Tract 04-01 J.N. 155-10 - Page Field density tests were taken at regular intervals to verify adequate compaction. Maximum dry density and optimum moisture content of representative samples of the on-site soils were determined in our laboratory in accordance with Test Method ASTM D 1557-07. The results of these laboratory tests are summarized in Table II. Visual classification of earth materials in the field was the basis for determining which of the maximum density values was applicable for a given density test. One-point checks were performed to supplement visual classifications. CONCLUSIONS Based on the results of our observations, on our field and laboratory tests, and on our experience and judgment, it is our opinion that the completed earthwork discussed herein has been performed in general accordance with our recommendations for processing of existing grades within the subject lots. Recompaction of the pad surfaces under the purview of this report has been completed under the observation of and with selective testing by Petra Geotechnical, Inc., and is found to be in compliance with the Grading Code of the City of Carlsbad, California. The completed work has been reviewed and is considered adequate for the construction now planned. Foundation design recommendations provided in Reference Nos. 3 and '4 remain applicable and no further recommendations are needed at this time. REPORT LIMITATIONS A representative of Petra Geotechnical, Inc. (Petra) was present on-site on an on-call basis during post-grading operations for the purpose of providing the owner's representative with professional opinions and recommendations. These opinions and recommendations were developed based on field observation and selective testing of the contractor's work. Our scope of services during this project did not include supervision or direction of the contractor, his personnel or his subcontractors. As documented in this report, our observations and testing did not reveal any obvious deviations from the recommendations provided in the referenced geotechnical reports by our firm; however, Petra does not in any way guarantee the contractor's work, nor do our services relieve the contractor (or any subcontractors) of their liability should any defects subsequently be discovered in their work product. Based on our findings, this report was prepared in conformance with generally accepted professional engineering practices, and no further warranty is implied nor made. WARMINGTON RESIDENTIAL CALIFORNIA May 10, 2011 Lots 3 through 6 of Tract 04-01 J.N. 155-10 Page 3 This report is subject to review by the controlling authorities for the project. Should you have any questions, please do not hesitate to call. Respectfully submitted, PETRA GEOTECHNICAL, INC. No. G 024 Mm Siamak Jafroudi, PhD Senior Princip al Engineer GE 2024 SM/SJ/kg W:\2010\100\155-10 Warmington Residential California (Black Rail)\300\Summary of Observation & Testing (Lots 3-6)doc WARMINGTON RESIDENTIAL CALIFORNIA May 10, 2011 Lots 3 through 6 of Tract 04-01 J.N. 155-10 Page 4 REFERENCES Christian Wheeler Engineering, Report of Field Observation and Relative Compaction Testing, Grading and Site Improvements, Black Rail 16-Lot Development, Black Rail Road and Songbird Ave., Carlsbad, California: prepared for Watkins Landmark Construction, dated January 4, 2007 (CWE 2050489.05). Geotechnical Commentary on Design and Construction of Post-Tensioned Slabs On-grade for Lots 1 through 16 Carlsbad Tract No. 04-01, The Poinsettia Ridge Project, Southeast Corner of Black Rail Road and Songbird Avenue, City of Carlsbad, San Diego County, California, letter by Petra Geotechnical, Inc., dated April 1, 2010. Geotechnical Review of Precise Grading Plans and Updated Foundation Design Recommendations, Lots 1 through 16 Carlsbad Tract No. 04-01, The Poinsettia Ridge Project, Southeast Corner of Black Rail Road and Songbird Avenue, City of Carlsbad, San Diego County, California, letter by Petra Geotechnical, Inc., dated April 13, 2010. Response to City of Carlsbad Review Sheet and Review of Precise Grading and Foundation Plans, Lots 1 through 16, Carsbad Tract No. 04-01, The Pointsettia Ridge Project, Southeast Corner of Black Rail Road and Songbird Avenue, City of Carlsbad, San Diego County, California, letter by Petra Geotechnical, Inc., dated July 14, 2010. I. WARMINGTON RESIDENTIAL CALIFORNIA Lots 3 through 6 of Tract 04-01 TABLE! FIELD DENSITY TEST SUMMARY May 10, 2011 J.N. 155-10 Page 5 Date of Test Test No. Parcel Number Depth * (ft.) Moist. (%) Unit Wt. lbs./cu.ft. % Rel. Comp. Soil Type 5/5/11 1 - Lot #3 FG 11.7 117.2 93 A 5/5/11 2 Lot #4 FG io:i 118.3 94 A 5/5/11 3 Lot #5 FG 12.2 117.1 93 A 5/5/11 4 Lot#6 FG 10.0 116.0 92 A FG.- Finish Grade * - Depth Below Finish Grade TABLE II Soil Type : Optimum Moisture (%) Maximum Dry Density (pci) A - Silty Sand (SM) 10.0 126.0 ri 0 20 40 60 August 7 2009 2009007 EXPLANATION 111 Approximate Limits of This Report X -4 Approximate Location of Density Test Black Rail Road Carlsbad, California Warinington Residential of California PETRA GEOTECHNICAL, INC. J.N. 155-10 MAY 2011 PLATE 1 Poinsettia Ridge Tract # CT04-01 Phase 2/ lLots3,4,..5, 6 (4units Sequence Sheet Issued: 2/17/11 Color Roof Lot Plan Elevation Scheme Type Address 1 3 (4) 2 F 4 Flat 6657 Thrasher Place 4 (1) (4) 1 R S 9 "S" Tile 6659 Thrasher Place 5 (3) (4) 1 F 6 Flat 6658 Thrasher Place 6 (3) (4) 2R I 1 "S" Tile 6656 Thrasher Place Carlsbad, California 92011 Backwater valve/Split System Dropped Garages Deepened Footings Fire Sprinklers Note: The above items are to be confirmed by the superintendent referencing the Precise Grading Plan. Mix - Phase 2-4 Lots Plan Total E I 1 1 N/A 1 2 2 1 1 0 2 3 0 0 0 0 Total 2 1 1 4 F = French Provence I = ltalianate S = Spanish Arrnroved: Warminuton Residential California BLS: JWS: -i -1 TOT: 7 -I' I MW: DG: L. r H LJ A -------------- 11P oinsetha Carlsbad Tract O4O1 ka5ingran CD 1'8O' "'•--" I : 1164L EL ( CD CD CD LO I..C) (J)UH )LL._ 0) tI I d'T i41L{i A c Ii 0) - s ii-- 4-.- I Ii OLI --' J. I3 i --I A. oInsettIa f<icl&1 Carlsbad Tract No. 04-01 iasingan CD bcale 111 o0O CJ A Lot N M i ty1r Tff'Iiase I\\/Lo 16 Lof W, — --7 SII7-i' I <r_flfl P ILot 10 I\ I OT 1iiIllhIfli Lot 6 /J S!' . biiiIi1 Lot 1-4 I F Ifif Loj L rt Poinsettia Ridge Tract # CT04-01 Phase 2 Lots 3, 4, 5, 6 (4 units) Sequence Sheet Issued: 2/17/11 Color Roof Lot Plan Elevation Scheme Type Address 3 (4) 2 F 4 Flat 6657 Thrasher Place 4 (1) (4) 1 R S 9 "5" Tile 6659 Thrasher Place 5 (3) (4) 1 F 6 Flat 6658 Thrasher Place 6 (3) (4) 2R I 1 "S" Tile 6656 Thrasher Place Carlsbad, California 92011 Backwater valve/Split System Dropped Garages Deepened Footings Fire Sprinklers Note: The above items are to be confirmed by the superintendent referencing the Precise Grading Plan. Mix - Phase 2 -4 Lots Plan Total 1 1 N/A 1 2 2 1 1 0 2 0 0 0 0 Tctal 2 1 1 4 F = French Provence I = ltalianate S = Spanish Approved: Warminqton Residential California BLS: JWS: TOT: MW: DC: Orange County I Environmental I Corporate 4 PETRA 3190 Airport Loop Drive, Suite J-1 Costa Mesa, California 92626 T: 714.549.8921 F: 714.549.1438 past + present + future it's in our science Engineers, Geologists Environmental Scientists December 9,2010 J.N. 155-10 Grading Permit No.: GR10-13 Mr. Tom Tupman WARMINGTON RESIDENTIAL CALIFORNIA 3090 Pullman Street Costa Mesa, CA 92626 Subject: Summary of Observation and Testing, Reconditioning of Lots 11, 12, 13 and 14 of Tract 04-01, The Pointsettia Ridge Project, Southeast Corner of Black Rail Road and Songbird Avenue, City of Carlsbad, San Diego County, California References: See Attached List. Mr. Tupman: Presented herein are the results of our field observation and testing performed during reconditioning of the pad surfaces on Lots 11, 12, 13 and 14 of Tract 04-01. The purpose of this most recent grading was to restore the subject pads back to their original condition as they existed at the completion of rough grading (Reference No. 1). A single-family residence is proposed on each lot. OBSERVATIONS AND TESTING A representative of this firm provided observation and testing during re-conditioning of the pad surfaces on the subject parcels and lots. In general, the work was performed in the following manner: 1. All construction debris and weeds were removed from each parcel and lot. The existing pad surfaces on each lot were scarified to depths of 4 to 6 inches, watered as necessary to achieve near optimum moisture conditions, and then recompacted in place to a minimum relative compaction of 90 percent by wheel-rolling with a skip loader and a water truck filled to capacity. Field density tests were performed using Nuclear Test Method ASTM D 6938-08a. Test results are presented in Table I and approximate locations of the field density tests are shown on Plate 1. Field density tests were taken at regular intervals to verify adequate compaction. Maximum dry density and optimum moisture content of representative samples of the on-site soils were WARMINGTON RESIDENTIAL CALIFORNIA Lots 11, 12, 13 and 14 of Tract 04-01 December 9, 2010 J.N. 155-10 Page 2 determined in our laboratory in accordance with Test Method ASTM D 1557-07. The results of these laboratory tests are summarized in Table II. 6. Visual classification of earth materials in the field was the basis for determining which of the maximum density values was applicable for a given density test. One-point checks were performed to supplement visual classifications. CONCLUSIONS Based on the results of our observations, on our field and laboratory tests, and on our experience and judgment, it is our opinion that the completed earthwork discussed herein has been performed in general accordance with our recommendations for processing of existing grades within the subject lots. Recompaction of the pad surfaces under the purview of this report has been completed under the observation of and with selective testing by Petra Geotechnical, Inc., and is found to be in compliance with the Grading Code of the City of Carlsbad, California. The completed work has been reviewed and is considered adequate for the construction now planned. Foundation design recommendations provided in Reference Nos. 3 and 4 remain applicable and no further recommendations are needed at this time. REPORT LIMITATIONS A representative of Petra Geotechnical, Inc. (Petra) was present on-site on an on-call basis during post-grading operations for the purpose of providing the owner's representative with professional opinions and recommendations. These opinions and recommendations were developed based on field observation and selective testing of the contractor's work. Our scope of services during this project did not include supervision or direction of the contractor, his personnel or his subcontractors. As documented in this report, our observations and testing did not reveal any obvious deviations from the recommendations provided in the referenced geotechnical reports by our firm; however, Petra does not in any way guarantee the contractor's work, nor do our services relieve the contractor (or any subcontractors) of their liability should any defects subsequently be discovered in their work product. Based on our findings, this report was prepared in conformance with generally accepted professional engineering practices, and no further warranty is implied nor made. S • •• 34 WARMINGTON RESIDENTIAL CALIFORNIA December 9, 2010 Lots 11, 12, 13 and 14 of Tract 04-01 J.N. 155-10 Page 3 This report is subject to review by the controlling authorities for the project. Should you have any questions, please do not hesitate to call. Respectfully submitted, 4o PETRA GEOTECHNICAL, INC. rn Siamak Jafroudi,, GE 2024 Senior Principal gngineer /t/q/ SM/Si/kg W:\2010\100\155-10 Warmington Residential California (Black Rail)\300\Recertflcation Letter (Lots 1,2,7,8 of Tr 04-0 ).doc WARMINGTON RESIDENTIAL CALIFORNIA December 8, 2010 Lots 11, 12, 13, and 14 of Tract 04-01 J.N. 155-10 Page 4 REFERENCES Christian Wheeler Engineering, Report of Field Observation and Relative Compaction Testing, Grading and Site Improvements, Black Rail 16-Lot Development, Black Rail Road and Songbird Ave., Carlsbad, California: prepared for Watkins Landmark Construction, dated January 4, 2007 (CWE 2050489.05). Geotechnical Commentary on Design and Construction of Post-Tensioned Slabs On-grade for Lots 1 through 16 Carlsbad Tract No. 04-01, The Poinsettia Ridge Project, Southeast Corner of Black Rail Road and Songbird Avenue, City of Carlsbad, San Diego County, California, letter by Petra Geotechnical, Inc., dated April 1, 2010. Geotechnical Review of Precise Grading Plans and Updated Foundation Design Recommendations, Lots 1 through 16 Carlsbad Tract No. 04-01, The Poinsettia Ridge Project, Southeast Corner of Black Rail Road and Songbird Avenue, City of Carlsbad, San Diego County, California, letter by Petra Geotechnical, Inc., dated April 13, 2010. Response to City of Carlsbad Review Sheet and Review of Precise Grading and Foundation Plans, Lots I through 16, Carsbad Tract No. 04-01, The Pointsettia Ridge Project, Southeast Corner of Black Rail Road and Songbird Avenue, City of Carlsbad, San Diego County, California, letter by Petra Geotechnical, Inc., dated July 14, 2010. 5: S WARMINGTON RESIDENTIAL CALIFORNIA Lots 11, 12, 13, and 14 of Tract 04-01 - TABLE I FIELD DENSITY TEST SUMMARY December 8, 2010 J.N. 155-10 Page 5 Date of Test Test No. Parcel Number Depth * (ft.) Moist. (%) Unit Wt. lbs./cu.ft. % Rel. Comp. Soil Type 12/8/2010 1 Lot# 11 FG 12.2 116.6 93 A 12/8/2010 2 Lot #12 FG 12.7 116.3 92 A 12/8/2010 3 Lot# 13 FG 13.1 116.7 93 A 12/8/2010 4 Lot #14 FG 12.8 117.0 93 A FU - Finish Urade * - Depth Below Finish Grade TABLE II Soil Type Optimum Moisture (%) Maximum Dry Density (pc A - Silty Sand (SM) 10.0 126.0 '