SITE INFORMATION AND CORRESPONDENCE_FILE 2

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Mr. Ken Gillies Gillies Trucking 3931 Newton Road, Stockton Page 3 of Characterization of the pumping influences of the two wells on the plume of impacted groundwater, and the potential impact of the plume of impacted groundwater on the two wells; • Completion of the vertical and lateral delineation of impacted groundwater; Characterization of the hydraulic properties of pertinent units of the hydrogeological frame-work; An estimate of absorbed and adsorbed (sorbed) and dissolved masses of petroleum hydrocarbons on the site; Preparation of a fate and transport model of the petroleum hydrocarbons that demonstrates reduction of the hydrocarbon impact to acceptable levels that are protective of human health, sensitive receptors and groundwater resources, and that shows restoration of background conditions in a reasonable time-frame. At a meeting with you and your consultant on 15 August 2001 you had agreed to provide construction details or a video log of G-1 and to destroy G-1 and replace it with a well designed pursuant to current standards. This was directed by the EHD by letters dated 22 August 2001 and 26 October 2001. You agreed again to destroy the domestic well at the 13 November 2002 meeting, and your approved work plan dated 22 January 2003 included destruction and replacement of G-1. At your consultant's request, the EHD did grant a delay in the destruction of G-1 to evaluate the results of the CPT investigation, which has now been completed and reported. Rather than demonstrating that G-1 had no effect on the plume or was affected by the plume, the results of the investigation raised the EHD's concern with the well. The one sample collected and analyzed from CPT-2, located between the former UST pit and G1, contained total petroleum hydrocarbons quantified as diesel (TPH-d). This demonstrates that the plume of impacted groundwater is in the vicinity of G-1, but there is no additional CTP-2 data to aid in quantifying the plume. The 80-foot bsg grab water sample was lost (broken container) and no sample was collected at total depth of 100 feet below surface grade (bsg), thought by UEC to be the depth of G-1. A sand interval was detected and sampled at approximately 114 feet bsg in CPT- 1 that apparently correlates with a sand interval encountered in GT-11. A groundwater sample was not collected in that sand interval of GT-11. The CPT-1 sample had an increased dissolved TPH-d concentration compared to the 80-foot sample in that boring. Although UEC believes that G-1 is 100 feet deep, the EHD has a copy of a permit issued in 1997 to repair the pump in G-1 that gives an approximate depth of the well of 117 feet. This creates the potential that the Third Riverbank sand is impacted and may be supplying water to G-1. As the directive for destruction of G-1 has been long standing and you have agreed in the past to destroy and replace it, and as the recent investigation was inadequate to demonstrate that G-1 would neither impact nor be impacted by the plume of