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Ripon Farm Service IncorpWated Page 5 932 South Highway 99 East Frontage RoadOctober 18, 2011 Ripon, California 95366 . . TO-3 in soil-gas samples VP-1 through VP-3, respectively; TPH-d results were reported as non-detect by method TO-3, and ithe calculated cancer risk was zero using the Johnson and Ettinger model. The report is available on GeoTracker. 09/23/09 Date of letter from the EHD directing the submittal of a comprehensive site closure summary that included addressing the omission of the concentration of TPH-d [9,000 milligrams per kilogram (mg/kg)] detected in soil sample B-8 when comparing soil concentrations to Environmental Screening Levels (ESLs) established by the San Francisco Bay Regional Water Quality Control Board; the analytical methods TO-3 and TO-15 used to report the results for the soil gas samples when it appeared that water-phase calibration standards were used instead of vapor-phase calibration standards; and the rational for not following the work plan approved by the EHD to collect and analyze the soil gas samples for TPH-d by method TO-17. The letter.is available on GeoTracker. 11/10/09 Date of No Further Action Request (NFAR) submitted by Advanced GeoEnvironmental, Inc. The NFAR is available on GeoTracker. 03/03/10 Date of letter from the EHD directing a technical justification, supported by authoritative guidance, for the methodology used. to enter soil gas data into the Johnson and Ettinger Model to determine the potential risk posed by soil gas intrusion into buildings at the site; the laboratory report for the soil gas samples be revised.and resubmitted to reflect the app'r'opriatemethod used to analyze the I soil gas samples if water-phase calibration standards were used. instead. of vapor-phase calibration standards; and a rational for deviating from the approved work plan and not analyzing soil gas samples'for TPH-d by method TO-17, and a demonstration that the reported TPH-d results. were equivalent to those that would have been provided by method TO-17 and could be relied upon for making decisions. The letter is available on GeoTracker. 03/30/10 Date of Revised Vapor Intrusion Investigation Report submitted by Advanced GeoEnvironmental, Inc. that included revisions for the analytical methods used to report the soil gas results. The report is available on GeoTracker. 07/02/10 Date of letter from the EHD directing the submittal of the gas chromatography- mass spectrometry (GC-MS) chromatograms for�the TPH-d initial calibration curve, continuing calibration standards, method blanks, laboratory control sample and matrix spike that were associated with the three soil gas samples. The letter 3 is available on GeoTracker. i 07/31/10 Date of an email from Advanced GeoEnvironmental, Inc. stating that "Additional chromatograms for,TPH-d QA/QC for EPA method.8260 are not available, as the GCMS method did not use a TPH-d standard for evaluation." The email is available in the Unit IV files. 12/13/10 Date of letter from the EHD denying the results previously submitted for TPH-d and directing that the three soil gas samples:$e resampled by collecting the soil gas samples on solid adsorbent TO-17 tubes for analysis of TPH-d by method j TO-17, and directing a technical justification, , supported by authoritative guidance, for the methodology used to enter the soil gas data for TPH-g into the Johnson and Ettinger Model. The letter is available'on GeoTracker. 1