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TABLE 3:SOIL GAS SAMPLE DATA SUMMARY-VOCs 2461 North Wilson Way,Stockton,California 95205 Volatile Organic Compounds(VOCs)by U.S.EPA Method TO-15 Sample Sample Tetrachloro- Ethyl- 2-Butanone Carbon 4-Ethyl- tert- Location ID Date Depth e(hPyle a Benzene Toluene benzene o-Xylene p/m-Xylene Acetone (MEK) Disulfide 2-Propanol toluene Butanol (feet bgs) (pg/m') (pg/m3) (pg/m') (pg/m3) (pg/m') (pg/m3) (pg/m') (pg/m3) (pg/m') (pg/m3) (pg/m3) (pg/m3) SB-1 12/9/2024 5 ND<1.9 15 15 6.4 6.1 22 140 34 21 100 ND<0.71 ND<0.80 SB-2 12/9/2024 5 ND<1.7 24 79 96 150 400 240 86 49 32 17 ND<0.74 SB-3 12/9/2024 5 ND<3.5 31 56 170 240 680 380 84 27 58 17 ND<1.5 SB-4 12/9/2024 5 13 2.2 7.1 66 120 340 210 37 43 42 18 28 Comparison Values in pg/m3 ESLs, 67 14 44,000 160 5,000 10,000 4,500,000 730,000 -- -- -- -- Table SG-1,Commercial/Industrial Sites Petroleum Vapor Intrusion(PVI) 140 -- 1,600 -- -- -- Bioattenuation factor(BAF)of 0.1. -- -- -- VOCs by U.S.EPA Method TO-15 Helium by ASTM 1946-90 Methyl Iso- 1,2,4-Tri- 1,1,2- 1,3,5-Tri- Sample Sample Tetrahydro- 1 Helium Shroud Location ID Date Depth Hexane butyl Ketone Styrene furan methyl- Trichloro- methyl- Other VOCs Helium Concentration Maximum Helium Allowed' (MIBKI benzene ethane benzene (feet bgs) (pg/m') (pg/m3) (pg/m3) (pg/m3) (pq/m3) (pg/m3) (p9/m3) (pg/m3) % % SB-1 12/9/2024 5 16 13 ND<0.60 ND<0.58 ND<0.77 3.5 ND<0.39 ND<MDL ND<0.062 24.9 0.01245 SB-2 12/9/2024 5 18 50 ND<0.56 ND<0.54 15 ND<0.95 5.5 ND<MDL ND<0.068 24.6 0.0123 SB-3 12/9/2024 5 31 74 ND<1.1 ND<1.1 13 ND<0.95 ND<0.72 ND<MDL ND<0.14 27.2 0.0136 SB-4 12/9/2024 5 ND<0.56 41 6.7 14 16 ND<0.95 5.9 ND<MDL ND<0.078 30.8 0.0154 Comparison Values in pg/m3-ESLs, 440,000 130,000 -- -- 150,000 53 Varies -Z Table SG-1,Commercial/Industrial Sites Notes: Analysis performed by Torrent Laboratory,Milpitas,California pg/m3 Micrograms per cubic meter ND< Not detected at or above method detection limit(MDL)shown Helium reported as a percentage of total sample ' Helium used as a leak check compound,reported as a percentage(%)of total sample z Comparison value is 5%ppmv per California Department of Toxic Substances Control bgs Below ground surface -- Comparison value not established by the SFBRWQCB Bold Result exceeds a Comparison Value EPA Environmental Protection Agency Table SG-1 Subslab/Soil Gas Vapor Intrusion:Human Health Risk Levels Revision 2 Environmental Screening Levels(ESLs)established by the San Francisco Bay Regional Water Quality Control Board,July 2019 Supplemental Guidance:Screening and Evaluating Vapor Intrusion,Final Draft,February 2023 Project No.501222 1 of 1