Laserfiche WebLink
Case Closure Summary Page 2 <br /> t eking Underground Fuel Storage Tank P rlyam <br /> III- Release and Site Characterization Information (continued) <br /> Maximum Documented Contaminant Concentrations - Before and After Cleanup (tank removal) <br /> Contaminant Soil Soil Water Water Contaminant Soil Soil Water Water <br /> Before After Before After Before After Before After <br /> (in ppm) (in ppm) (in,ppm) (in ppm) <br /> TPH (Diesel) 1680 61 40 0.085 MTBE _:__ _.._ <br /> Benzene <0.02 NA <0.3 <0.0005 EDB <br /> Toluene <0.02 NA 0.015 <0.0005 Lead --- <br /> Ethylbenzene 0.23 NA 0.013 <0.0005 <br /> Xylene 0.65 NA 0.080 <0.0005 <br /> Multiple investigations indicated minimal diesel contamination remaining in the soil and groundwater. Approximately a total <br /> of 36.34 liters of free product have been removed from the most contaminated well MW-4 (the only well with free product) <br /> between 1993 to 1999 using a bailer and a skimmer. No free product has been observed in MW-4 since 1998, and the <br /> concentration of TPH-d in MW-4 has been reduced to 85 ppb according to the last sampling results in August 2003. <br /> Beneficial uses of groundwater are protected, now and in the future. <br /> Soil Before results from S82 at 10' bsg on 10/17/89. Soil After results from SB17 at 15' bsg on 09117/99. Water Before <br /> results from MW4 on 10124/89, Water After results TPH-d from MW4 on 08/12/03, BTEX 10/18/00. <br /> IV. Closure <br /> Does completed corrective action protect existing beneficial useper the Regional Board Basin Plan? Yes <br /> Does completed corrective action protect potential beneficial uses per the Regional Board Basin Plan? Yes <br /> 1- Does corrective action protect public health for current land use? Yes <br /> I� Site management requirements: none <br />+ Should corrective action be reviewed if land use changes?Yes <br /> 1 Monitoring wells decommissioned: yes Number Decommissioned: 7 Number retained: 0 <br /> List enforcement actions taken: NOR sent <br /> List enforcement actions rescinded: None <br /> V. Local Agency Representative Data <br /> Name: Don Heron Title: Director of Environmental Health <br /> i Signature: .' _�- Date: O <br /> i <br /> VI. Central Valley Regional Water Quality Control Board (RB)Notification <br /> i <br /> Res se Date: 03/09/04 <br /> on <br /> Date Submitted to RB: 02/19/04 p <br /> j RB Staff: James L. Barton Response: Concurrence with No Further Action Status <br /> Title: Assoc Eng Geologist <br /> i <br /> VII. Additional Comments, Data, etc. <br /> j Monitoring wells were all destroyed under permit and inspection <br /> This document and the related CASE CLOSURE LETTER, Shall be retained by the lead agency as part of the <br /> official site file. (08/24193) Exhibit N Page 2 of 2 <br />