Laserfiche WebLink
A . • <br /> Closure Appeal, <br /> Flag City Chevron,6421 Capitol Avenue,Lodi,California <br /> Page 3 of 5 <br /> Boring No. Concentration (mg/kg) Depth Defined Trend <br /> PI 0.14 35 <br /> P1 ND 45 Yes Decreasing <br /> P19 ND 5 <br /> P19 0.042 15 No Increasin¢ <br /> P20 0.013 15 <br /> P20 0.21 20 No Increasin¢ <br /> P22 ND 10 <br /> P22 0.57 15 No Increasing <br /> P23 ND 15 <br /> P23 0.011 20 No Increasing <br /> P24 ND 15 <br /> P24 0.068 20 No Increasing <br /> P25 ND 10 <br /> P25 0.011 20 No Increasing <br /> P26 ND 10 <br /> P26 0.011 20 No Increasing <br /> P31 0.012 3 <br /> P31 0.270 10 No Increasing <br /> P32 0.028 10 No Only Sample <br /> P34 0.18 10 No Only Sample <br /> P40A 0.022 30 <br /> P40A 0.071 45 No Increasing <br /> P41 0.052 30 <br /> P41 ND 45 Yes Decreasing <br /> P43 0.39 30 <br /> P43 ND 45 Yes Decreasing <br /> MW-19 0.25 18 <br /> MW-19 0.14 30 No Decreasing <br /> The Closure Summary Report prepared by AGE dated August 31, 2005 calculates the thickness <br /> of the contaminated soil zone at 16 feet (b=8 feet where b is half the thickness of the soil <br /> contamination zone). As shown in the table above, the contaminated zone extends from 3 to 45 <br /> feet bgs and has not been adequately defined. The thickness is at a minimum of 30 feet thick and <br /> undefined vertically. In addition, the majority of the soil samples analyzed for MTBE were <br /> collected below the water table and away from the source. Therefore, the average value of <br /> detected MTBE, which was used to calculate the mass in soil, was statistically skewed very low. <br /> Apex recommends conducting a soil vapor survey at the Subject Property to assess current <br /> TPHG, benzene, and MTBE concentrations in soil in the vadose zone. <br />