SITE INFORMATION AND CORRESPONDENCE

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Mr. Sheldon Heckman - ? - 10/02/01 Mr. Richard Calone, Esq., Richard Calone, Inc. Tetrachloroethene (PCE, 68 µg/kg) was detected in soil during a previous investigation. PCE was not detected in groundwater, although analyses revealed daughter product 1,2-dichloroethane (1,2-DCA, 25 4g/L) Comments: 1. The groundwater monitoring well logs are incomplete. MW-2 and MW-5 are missing litholoQy; others have gaps in the soil classification. The logs show that one well (MW-1) was completed with screened intervals almost entirely in the clay formation, below saturated sand and gravel layers. Another well, MW-6, was screened entirely in twenty feet of clay, below saturated sand and gravel layers. Additional new monitoring wells screened across higher permeability soils are needed. If free phase product (separate phase petroleum product, or SPP) occurs at the water table in monitoring wells, then skimming of SPP from an extraction well(s) and groundwater treatment will be required. 2. We agree that an additional investigation is needed to characterize the lateral extent of petroleum hydrocarbon and chlorinated solvent contamination in soil and groundwater. The additional investigation(s) should also determine whether bioremediation of petroleum hydrocarbon and chlorinated solvents is occurring in soil and groundwater. 3. The text does not summarize the previous site investigation results, but uses results of that earlier investigation to conclude that most contamination occurs between 10 feet and 80 feet below ground surface. This investigation analyzed samples between 45 and 100 feet. Future reports should summarize all previous investigations. 4. Section 5.0 Conclusions: The text focuses on the hydrocarbon contaminants, and does not discuss the chlorinated solvents detected in soil and groundwater. Future reports should provide a detailed discussion of all constituents and their potential source(s). 5. Figure 4 shows nine monitoring wells using the symbol "UST Investigation Monitoring Well Location", but does not identify these wells with names. The wells have not been used to construct the groundwater gradient map. Please label the UST wells, take water levels if possible, and provide well construction logs in future reports. Please ensure that future reports address the comments above. In addition, by 15 November 2001, provide a detailed interim remedial action work plan, prepared in general accordance with Attachment A (Items To Be Included In A Site Assessment Work Plan), which includes, at a minimum, a. the installation of additional groundwater monitoring wells, b. the characterization of the vertical and horizontal extent of both petroleum hydrocarbons and volatile organic compounds in soil and groundwater c. analyses of additional water quality parameters, to aid in assessment of the degree of bioremediation occurring at the site.