SITE INFORMATION AND CORRESPONDENCE

Home Browse Search

TA13tt 1 - CHECKLIST OF REQUIRED tPATA FOR NO FURTHER ACTION REQUESTS AT UNDERGROUND TANK SITES Site Name and Location: Frank's Tire Shop, 5023 North Market Street, Linden, San Joaquin County 1. Distance to production wells for municipal, domestic, agriculture, The County reported two municipal wells at 1500 feet. industry and other uses within 2000 feet of the site; Both well have deep seals,.and deep perforated intervals. 2. Site maps, to scale, of area impacted showing locations of former and existing tank systems, excavation contours and sample locations, boring and monitoring well elevation contours, Site maps provided. gradients, and nearby surface waters, buildings, streets, and subsurface utilities, YE 3. Figures depicting lithology(cross section), treatment system diagrams; Boring logs show predominantly silts to sand. ETI 4. Stockpiled soil remaining on-site or off-site disposal(quantity); Disposition of excavated soil was not presented. ENJ 5. Monitoring wells remaining an-site, fate; Monitoring wells were not installed. N 6. Tabulated.results of all.groundwater elevations and depths to water, Depth to water is reported at 128 feet bgs(Linden Water). Groundwater samples were not collected. �y 7. Tabulated results of all sampling and analyses: Maximum results in soil show TPHg at 3,000 mg/kg at 10 feet bgs,and 92 mg/kg at 25 feet bgs. Maximum benzene at 3.2 mglkg at 10 feet,and Detection limits for confirmation sampling <0.05 mg/kg at 15 feet. Maximum TEX at 43 mg/kg,32 mg/kg, and 240 Lead analyses mg/kg,respectively. Maximum MtBE at 0.035 mg/kg in tank pit at 9 feet. Maximum lead was 17 mg/kg in tank pit at 9.5 feet 8. Concentration contours of contaminants found and those remaining in soil Lateral extent of contaminated soil is jand groundwater, and both on-site and off-site: defined. Vertical extent dehned down to 25 Lateral andN❑ Vertical extent of soil contamination feet bgs. Groundwater was not F1 Lateral and a Vertical extent of groundwater contamination encountered at a maximum depth of 31 feet. 0 9. Zone of influence calculated and assumptions used for subsurface A remediation system was not operated at remediation system and the zone of capture attained for the soil and this site. groundwater remediation system; 10.Reports/informationUnauthorized Release Form QMRs Y❑ Boring logs PAR E] FRP N❑ OtherN❑ 0 11.Best Available Technology(BAT) used or an explanation for not using BAT,. Remove USTs and contaminated soils. 12.Reasons why background was/is unattainable using BAT, Concentrations of TPHg and BTEX exist in site soils. 13.Mass balance calculation of substance PTI treated versus that remaining; Based on tank pit and boring sampling results, approximately 23 pounds of TPHg,and 0.015 pounds of benzene remain in site soils. 14.Assumptions,parameters,calculations and model used in risk A risk assessment was not completed. 0 assessments, and fate and transport modeling; 15. Rationale why conditions remaining at site will not adversely TPHg and BTEX constituents in soil show attenuation J mpact water quality, health, or other beneficial uses;and with depth. Depth to rirst water is reported at 128 feet. By: Comments: One waste oil, and two 1,000-gallon gasoline USTs were removed in 1998 to 1999. TPHg,BTEX, and low concentrations of MtBE were identified in the tank pit excavations. Four soil borings were completed. TPHg in SB3 was identified at 3,000 mg/kg at 10 feet, and decreased to 92 mg/kg at 25 feet. The vertical extent of soil contamination below 25 feet has not been defined. MtBE was detected in initial tank pit samples;however, soil boring samples were Date: non detect for all fuel oxygenates using 8260 analysis. The County reported two Linden Water District wells within 1500 feet of the site. Linden Well 6 is sealed to 160 feet, and the first perforations start at 748 feet. Linden Well 7 is sealed to -//00 300 feet, and the first perforations start at 460 feet. Linden Water District reports the depth to water is currently 128 feet bgs. Based on information provided, Board staff concur with San Joaquin County's Closure Recommendation.