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Environmental Mr.Michael J.Infurna Resources 16 December 1998 Management Page 3 On 28 August 1998, ERM went to the site to locate the wells,visually evaluate the condition of their surface features, and determine if any materials were present within the casing. We found that some of the locations had been impacted due to site grading activities. The following is a summary of current well conditions: • The christie box and casing were intact for wells MW-2 and MW-6, and there were no apparent obstructions within the wellbores. • Although the christie box was missing for wells MW-3, MW-4, and MW-5, the casing was intact in each, and there were no apparent obstructions within the wellbores. • The christie box for well MW-1 was missing and the casing was broken at the surface. There was approximately 5.5 feet of material at the bottom of the well (extrapolated from well construction details in the boring/well log). PROPOSED SCOPE OF WORK The proposed scope of work is to abandon the six existing monitoring wells,which are no longer utilized. As noted above, dissolved lead has not been detected in ground water samples from any of the six on-site monitoring wells during historical monitoring. Based on these results, ERM intends to abandon all six monitoring wells on behalf of UPRR. All proposed abandonment activities will be performed by a California licensed C-57 drilling subcontractor, under the direction of a California Registered Geologist (R.G.). Upon mobilizing to the field, ERM will sound each well to confirm findings from our earlier site visit and verify,based on information presented in the original well logs,if any additional silting, bridging or casing failure has not occurred. Wells with less than 3 feet of silt and with intact casing will be pressure grouted by pumping neat cement into the casing through a tremmie pipe extending to within 3 feet of the bottom of the casing. While filling the casing, an external pump will be used to create additional pressure at the wellhead. The external pump will be plumbed through fittings installed on a pressure resistant cap installed on the wellhead. Additional external pressure will be maintained until the well ceases to accept any additional grout. After the grout has hardened, the wellhead will be removed.