SITE INFORMATION AND CORRESPONDENCE_2

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L v Ron Rowe Registered Environmental Specialist February 2, 2000 Page 5 stockpiled soils. These two sample points yielded contamination levels of 183 and 20 mg/kg. Neither their location nor methodology is revealed. We do not believe that two samples could be used to accurately measure the stockpiled soil, which is estimated to have been approximately 11,000 cubic feet (or 400 cubic yards) based on a written description of the work by Exeltech. This stockpiled material was placed back into the excavation. The cleanup level of up to 999 mg/kg was inappropriate as it represents a high concentration of gasoline in soil and a significant source of potential contamination to groundwater. The volume of gasoline still present in the contaminated soils that were back-filled into the excavation could have been significant and could very well account for most of the gasoline present in soil and groundwater in 1991,prior to the onset of air sparging and vapor extraction. Therefore, it is possible that the primary source of gasoline to soil and groundwater at the site was the backfilled soil that still contained high concentrations of gasoline. It appears from the work proposal from Exceltech that a concrete pad had been in place above the USTs before demolition. This would have limited surface water intrusion. The removal of the concrete pad would have exacerbated the downward migration of the gasoline due to surface water infiltration over the six-year period between 1985 and thereafter. SITE REMEDIATIONAND COUNTYREGULATORYINTERACTION In the late 1980's, the County notified Del Monte about the potential for contamination under its Property 5, and in 1990, the County named Del Monte a responsible party for the Property. In 1991, Del Monte removed the product lines and in the process identified an oil/water separator. Del Monte hired a consultant in or about 1990 (CH2M Hill), and from 1990-1994, the consultant conducted an environmental investigation and proposed various remediation strategies. In 1994, Del Monte insisted that the County name Parmaceast as a responsible party. In December 1994, the County named Parmaceast as a responsible party, ostensibly based on Del Monte's representation that Parmaceast "owned and operated the underground storage tanks prior to discontinuation of their use." Apart from the fact that Parmaceast did not own or operate the USTs, and the USTs were maintained in operating condition and were not "discontinued" prior to the 1976 sale or the Property, there is evidence that the gasoline found on the Property was refined some time after 1979 since tertiary-butyl alcohol ("TBA") is affecting the groundwater at concentrations that can only be reconciled with a release occurring after 1976. This new information further calls into question Del Monte's assertions that it never used the USTs. 5 At this time, Del Monte had a number of other tanks on the Property as well. Documentation reveals that many of those tanks leaked. 761778.3