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Home My WebLink AboutCDP 15-52; SCHMALTZ RESIDENCE; FINAL REPORT OF TESTING DURING RE-GRADING; 2016-11-15GEOCON INCORPORATED GEOTECHNICAL • ENVIRONMENTALu MATERIALS Project No. 05851-52-07 November 15, 2016 •'•' I Mr. Joseph Schmaltz - 6349 Alexandria Circle Carlsbad, California 92011 Subject: FINAL REPORT OF TESTING AND OBSERVATION SERVICES PERFORMED DURING SITE RE-GRADING OPERATIONS SCHMALTZ RESIDENCE , - LA COSTA DOWNS BLOCK 22, UNIT NO. 1— LOT NO. 4' 6468 FRANCISCAN ROAD CARLSBAD, CALIFORNIA - References: 1. Final Report of Testing and Observation Services, During Site Regrading, La Costa Downs Block 22, Unit No. 1 - Lot Nos. 1 through 11, prepared by Geocon Incorporated, dated January 24, 1997 (Project No. 05851-12-01). 2. Update Geotechnical Report, Schmaltz Residence, La Costa Downs Block 22, Unit No. 1 - Lot 4, 6468 Franciscan Road, Carlsbad, California, prepared by Geocon Incorporated, dated January 13, 2016 (Project No. 05851-52-07). Dear Mr. Schmaltz: In accordance with your request, we provided compaction testing for the subject lot. The upper two feet of the existing fill soil on the lot was processed, moisturized as necessary, and compacted. Our services took place on October 31, 2016. The scope of our services consisted of performing in-place density tests and collect a soil sample for laboratory testing. We performed in-place density tests using a nuclear gauge in accordance with ASTM D 6938. We performed laboratory tests on soil samples in accordance with ASTM D 1557, Maximum Dry Density and Optimum Moisture Content; ASTM D 4825, Expansion Index; and California Test No. 417, Water-Soluble Sulfate Content. The results of the in-place density tests are summarized in Table I and laboratory tests are summarized in Table II through IV. Results of in-place density tests indicate that the subgrade materials possess a dry density of at least 90 percent of the laboratory maximum dry density near to slightly above the optimum moisture content at the locations tested. Based on observations and test results, it is the opinion of Geocon Incorporated that the re-grading the pad, which is the subject of this report, has been performed in substantial conformance with the recommendations of the project geotechnical report. The test results of the finish grade soils indicated a lower than optimum moisture content. In place density tests, however exceeded the minimum requirements. The loss of moisture can be attributed to evaporation. The recommendations presented in our update report remain applicable for the design and construction of the planned residence. Additional improvement installation performed at the site should be 6960 Flanders Drive 6 San Diego California 92121-2974 • Telephone 858 558 6900 S Fax 858 558 6159 AS:SFW:dmc (2) Addressee : 44 cc No 1778 * CERTiFIED ENGINEERING GEOLOGIST . PPCAt accomplished in conjunction with our observation and testing services. This office should be notified at least 48 hours prior to commencing additional grading or backfill operations. If you have any questions regarding this letter, or if we may be of further service, please contact the undersigned at your convenience. Very truly yours, GEOCON INCORPORATED Au Sadr Shawn Foy Wee on CEG 1778 MAI GE 2714 Project No. 05851-52-07 -2- November 15, 2016 OD GEOCON Project Name: Schmaltz Residence TABLE I SUMMARY OF FIELD DENSITY TEST RESULTS Prolect No.: 05851-52-07 • Elev. Max. Opt. Field Field . Required Test No. or Curve > %" Dry Moist Dry Moisture Relative . Relative Date ... .. - Location .. Depth No. Rock Density Content Density Content Compaction Compaction 0 0/ o) - - Re. (feet) (pci) (%) (pci) (%) Pre. No. FG 1 - 10/03/16 E Side Bldg Pad . - 0.0 1 0 134.3 8.4 124.6 6.3 93 90 FG 2 - 10/03/16 W Side Bldg Pad 0.0 1 0 134.3 8.4 130.3 6,5 97 90 - 10/03/16 E Side Bldg Pad 0.0 1 0 134.3. 8.4 126.2 8.1 94 90 r 3 4 - 10/03/16 W Side Bldg Pad 0.0 1 0 134.3 8.4 127.6 8.8 95 90 I - - I - - - - —- .4 TABLE I EXPLANATION OF CODED TERMS TEST NO. PREFIX AC Asphalt Concrete IT Irrigation Trench SL Sewer Lateral AD Area Drain iT Joint Trench SM Sewer Main B Base M Moisture Test SR Slope Repair CG Curb/Gutter MSE Mechanically Stabilized Earth Wall ST Slope Test DW Driveway RG Regrade SW Sidewalk ET Electrical Trench RWL Reclaimed Water Lateral SZ Slope Zone ETB Exploratory Trench RWM Reclaimed Water Main UT Utility Trench FB Footing Backfill SBT Subdrain Trench WB Wall Backfill FG Finish Grade SD Storm Drain WI Water Lateral GT Gas Trench SG Subgrade WM Water Main TEST NO. RE. A, B, C, ... Retest of previous density test failure following additional moisture conditioning or recompaction R Fill in area of density test was removed during construction operations ELEVATION OR DEPTH Corresponds to the elevation or the depth, in feet, of the in-place density/moisture content test. The value has been rounded to the nearest whole foot CURVE NO. Corresponds to the curve numbers presented in the summary of the laboratory maximum dry density and optimum moisture content test results. The field representative selected the curve no. based on the laboratory test results and field observations >W' ROCK - ROCK CORRECTION The laboratory maximum dry density and optimum moisture content can be adjusted for in-place soil that possesses rock larger than 3/4 inch. The curve no. is adjusted for the percentage of 3/4 inch rock in accordance with ASTM D 4718 or Woodward Clyde guidelines. TABLE II SUMMARY OF LABORATORY MAXIMUM DRY DENSITY AND OPTIMUM MOISTURE CONTENT TEST RESULTS ASTMDI557 Maximum Optimum Sample No. Description Dry Density Moisture Content (pci) (% dry weight) 1 Dark reddish brown, Silty fine to medium SAND 134.3 8.4 '4 iO13CBC ixpansion assification n-Expansive mber 15, 2016