SITE INFORMATION AND CORRESPONDENCE

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r Mr. Ken Price • - 2 - • 7 March 2002 corresponding monitoring data from the network of permanent monitoring wells at 1904 Charter Way and on the Bridgeport property. Monitoring Well Network On the Bridgeport property, there are five permanent and seven temporary monitoring wells in the shallow zone and two permanent wells in the intermediate zone. Oxychem proposes to abandon three of the permanent shallow wells and four of the temporary shallow wells, and convert three temporary wells into permanent wells by adding well head protection. These changes to the monitoring well network will allow the Bridgeport development to proceed with grading and building activities. The Well Work Plan is approved as proposed. Accordingly, the following wells are to be abandoned: MW-12,MW-13, MW-14, TW-A, TW-C, TW-E, and TW-G. Wells to be converted to permanent monitoring wells are: TW-B, TW-D, and TW-F. In our 1 March 2002 telephone conversation, Mr. Tim Souther of Geomatrix stated that the MW-22 well head was damaged and inspection and repair is scheduled for the first week of March. In our 5 March telephone conversation,Mr. Souther and I discussed revising the MRP and removing some of the intermediate zone wells. The damaged intermediate zone well, MW-22, is one of the wells considered to be removed. Therefore, Oxychem may either repair or abandon MW-22 at this time. Mr. Souther anticipated completing the well closure,repair and conversion work by the end of March and proposed to submit a summary of the implemented Well Work Plan and provide an updated map including the Brideport street layout in relation to the Oxychem facility in the First Trimester 2002 Monitoring Report which is due 10 June 2002. This is acceptable. Concentrations of 1,2-DCP range from 100 to 230 ug/1 on the Oxychem site near the downgradient boundary contiguous with the Bridgeport property. On the Bridgeport property within 200 feet of this boundary, nine of the ten wells contain 1,2-DCP in concentration less than 30 ug/l, or do not contain it at all,whereas TW-E, also on the Bridgeport property, contains 100 ug/l of 1,2-DCP. Mr. Souther pointed out that an underground fuel tank was removed from the norteastern portion of the Oxychem property, and that the petroleum may have contributed to degradation of 1,2-DCP, possibly explaining the lower concentrations found in many of these downgradient wells. The presence of 1,2-DCP at 100 ug/l in TW-E suggests that 1,2-DCP may extend beyond the existing monitoring well network in the southeastern direction. By 15 April 2002, Oxychem needs to provide a work plan to define the limits of 1,2-DCP between TW-G and MW-25. Groundwater Gradient The annual groundwater monitoring reports show an overall groundwater gradient towards the east,with a pattern of localized groundwater mounding beneath the facility