SITE INFORMATION AND CORRESPONDENCE FILE 1

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4491 Durham Ferry Page 2 Correspondence dated May 1, 1995 This correspondence was included as cover to the "Quarterly Monitoring Report" and included reference to two Limited preleminary xtraction swells and ats. The �teptdrawdoincluded test of tmeasurhe nt of oxygen concentration in the vapor performance of the groundwater extraction well. PHS/EHD has requested on many occasions to be notified 48 hours prior to any site activity. Please be informed that PHS/EHD was notified on April 24, 1995 that a site visit was to be made that day to do some pre-pump test planning. It was further indicated that within the next 10 days that the pilot testing would be scheduled. Correspondence dated May 9, 1995 The correspondence was faxed under cover which indicated that review was not imperative. The correspondence was prepared to support the request to alter the scope of work for the feasibility testing. The correspondence indicated that Clearwater had mobilized for a site visit, several weeks prior, to complete a well yield test. Well yield studies are generally part of a two phase pump test. it was stated that it was not possible to use a submersible pump due to the low water recharge. It was suggested that the low recharge observed was a result of a poor formation transmissivity and a marginal filter pack. The marginal filter pack was stated to be due to the flowing sands encountered during well installation that prevented the placement of the most appropriate amount of "gravel". The PHS/EHD inspector on site did not note heaving sands during RW1Is installation nor was the volume of sand installed reflective of a well pack deficiency. The correspondence also indicated that low levels of oxygen existed. This statement was not supported with quantitative values nor was the testing methodology explained. Recommendations included: well development and an alteration of the groundwater treatment and vapor extraction feasibility testing which was included in the pre-approved work plan. PHS/EHD approved the proposed well development, although it should be noted that PHS/EHD recommended development prior to the placement of the bentonite plug at the time of well installation. The effects of well development must be evaluated before an alteration of the proposed feasibility may be approved. Should the recovery well achieve improved production performance, as a result of the well development, the proposed dual phase test would likely not be possible, since it will depend on a low flow pump to dewater the recovery well. A proposal to extend the testing for five days, and to perform slug tests on the monitoring and domestic well was also included. The correspondence also stated that modifications would be submitted to George Lockwood for pre-approval and then the proposed recommendations would be initiated.