SITE INFORMATION AND CORRESPONDENCE

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Mr. Jerry Lile July 17, 2000 Page 2 USTs have also been removed from Area 16. Area 20 was used as a switching yard. A portion of Area 21 is used as a dairy distribution center. A UST was removed from Area 21 and floating product has been historically observed. Comments and Recommendations AREA 10 1) Page 25, third paragraph: It is indicated for Area 10 that elevated concentrations of contaminants other than lead or petroleum hydrocarbons, such as arsenic, were detected at concentrations far below the California hazardous waste criteria or preliminary remediation goal (PRG) for industrial sites established by the United States Environmental Protection Agency. The PRG value for arsenic screening was the non- carcinogenic value. The 10' risk value PRG for arsenic is 2.7 mg/kg. Table 3 of the report indicates that the sample collected from a depth of 3 feet below ground surface from boring 1 OB-24 contained arsenic at a concentration of 88 mg/kg. This arsenic concentration could be of potential concern. Recommendation Consideration should be given to the appropriateness of using the carcinogenic PRG for arsenic. 2) Arsenic was detected in one groundwater sample collected from boring 10B-3 at 5.3 mg/L. This concentration exceeds the Maximum Contaminant Level (MCL) of 0.05 mg/L. Recommendation Potential risks associated with arsenic in groundwater should be evaluated in the risk assessment. 3) Page 26, fourth paragraph: It is indicated that one polycyclic aromatic hydrocarbon (PAH) was detected in four samples at concentrations that exceed the residential PRG. It is unclear which PAH exceeded the PRG four times and from which borings these samples were collected. A review of Table 2 indicates that benzo(a)pyrene (B(a)P) exceeded the industrial soil PRG value three times for recent investigation soil samples collected from Area 10. One soil sample from Area 11 exceeded the industrial soil PRG for B(a)P. C:\OFFICE\WPWIN\WP000S\VJPSUITEW ORSHRI.WPD