ARCHIVED REPORTS_FOURTH QUARTER AND ANNUAL 2010 SITE STATUS, REMEDIAL SUMMARY, AND GROUNDWATER MONITORING REPORT

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Table 11 Dual Phase Extraction System -Groundwater Analytical Data Parcel 2A-L&M OU 666 West Weber Avenue, Stockton, CA HEM Ethyl- Total Date TRPH w/SGT TPHg TPHd TPHo Benzene Toluene benzene Xylenes MtBE DIPE ETBE TAME TBA Sampled Sample ID Notes pH (mg/L) (mg/L) (Ng/L) (Ng/L) (Ng/L) (Ng/L) (pg/L) (pg/L) (pg/L) (pg/L) (pg/L) (pg/L) (Ng/L) (Ng/L) Definitions(continued): MtBE =Methyl tert-butyl ether -- =Not analyzed or not applicable < =Value is less than laboratory reporting limit pH =Concentration of hydrogen ions TAME =Tertiary-amyl methyl ether TBA =Tertiary-butyl alcohol TPHd =Total petroleum hydrocarbons as diesel(diesel range organics) TPHg =Total petroleum hydrocarbons as gasoline(gasoline range organics) TPHo =Total petroeum hydrocarbons as motor oil(motor oil range organics) TRPH =Total recoverable petroleum hydrocarbons HEM w/SGT =Hexane extractable material with silica gel treatment POTW =Publically Owned Treatment Works Notes: 1 =System permitted under ATC No. N-4878-1-1. Source test for air board. Extracted groundwater being held in onsite holding tank. System shut down following source test. 2 =Source test for air board. System shut down following source test due to on-site excavation activities. 3 =Wastewater not discharge to sanitary sewer,stored in onsite holding tank. 4 =Repeat analysis for TPHg yielded inconsistent results,the highest value detected is reported as an estimate. 5 = System shut down following completion of vapor PAH sample collection. 6 =Hydrocarbons reported as TPHo do not exhibit a typical Motor Oil chromatographic pattern. 7 =No sampling due to system not operating. No discharge past 6/3/2005 until 7/6/2005. 8 =pH sample collected on 10/20/2005 due to exceedance of holding time on pH sample collected on 10/18/2005. 9 =System offline from 12/7/06 to 5/30/07 for construction.System restarted on 5/21/07and sampled on 5/31/07. 10 =pH sample tested using standard method SM-4500-HB out of 15 minute holding time. 11 =Sample analyzed using a bottle that contained a headspace bubble greater than 1/4 inch in diameter. 12 =Matrix/Spike Duplicate results for the analyte toluene were affected by the analyte concentrations already present in the un-spiked sample. 13 =Repeated analysis yielded inconsistent results for the analyte ethylbenzene. The concentrations appear to vary between bottles. The highest valid results are reported. 14 =Matrix/Spike Duplicate results for the analyte benzene were affected by the analyte concentrations already present in the un-spiked sample. 15 =Surrogate Recovery for method Mod. EPA 8015 was outside of control limits. This may indicate a bias in the analysis due to the sample's matrix or an interference from compounds present in the sample. 16 =Matrix Sike/Matrix Spike Duplicate Results for the analyte Tert-Butanol were affected by the analyte concentrations already present in the un-spiked sample. 17 =Hydrocarbons reported as TPHd are higher boiling than typical diesel fuel. 18 =Hydrocarbons reported as TPHg are primarily compounds not found in typical gasoline. 19 =Hydrocarbons reported as TPHo are lower boiling than typical motor oil. 20 =TRPH by EPA Method 418.1 is being phased out due to the use of chlorinated fluorocarbons(CFCs)as the extractable agent.An acceptable replacement method has been EPA 1664 in which hexane is used as the extractable agent in lieu of CFCs. Hexane extractable materials coupled with silica gel treatment(HEM w/SGT by EPA 1664)is an accepted replacement analysis for TRPH by EPA 418.1 with the exception that two compounds are only extractable with CFCs that are not extractable with HEM w/SGT. In addition,according to the City of Stockton MUD discharge permit, received by Stantec on October 28,2008 HEM w/SGT is acceptable. 21 =EPA Method 524.2 requires the inclusion of a field blank with each set of drinking water samples submitted to the laboratory. No field blank was identified in this sample set. \\Us1345-f01\secor\projects-077\Tidewater\TW Stockton(Parcel 2A-0415)\Engineering\O&M\Tables\O&M Tables 2010\4Q10\Parcel 2A OM Tables 4Q10.xlsx Page 13 of 14