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OPR-21.-1995 15: 13 MONTGOMERY WATSON 510 975 3412 P.02iO4 Revised Access Recommtienc During the resulting site visit with Layne-Western, we determined that the column pipe appears to be sand-locked in place at approximately 120 feet below grade. Additional fishing for the pipe and bowls would therefore be not be effective; based on previous experience at this well,the friction resulting from 60 feet of sand-locked column pipe against the well casing is too great to overcome. Therefore,we recommend the following modifications to the previously recommended procedures. The depth of the top of the bowls is approximately 160 feet bgs. The central shaft broke off at the top of the bowls during previous efforts and has been removed from the well. The following activities will therefore be performed at well AG-3: I, Cut the column pipe at approximately 160 feet bgs. If the bowls are not sand-looked in place,they may fall to the bottom of the well and save considerable drilling time and costs. 2. If the bowls do not drop,cut the column pipe at approximately 125 feet bgs and remove the upper portion of the column pipe from the well. The column pipe is currently broken off at 40 feet bgs. 3. Using a bit smaller than the column pipe,mill out the bowls. This will break up the bowls sufficiently so that the pieces will drop down in the well if it is clear. The portion of the sand-locked column pipe(35 feet) will remain in place and will be grouted in that location during final abandonment operations, 4. Perform a total depth measurement. Based on the results of the measurement,we will either assess the condition of the well as described in the work plan if the well is open below the bowls or proceed with the contingency recon:uneridations described below if it is not. Contingericy Recommendations The following recommendations were discussed in the November 1994 RPM meeting in the event that the well casing is not cleared by milling out the bowls of the pump. 1. If further obstructions are determined to be present, the 'ulterior of the well casing will continue to be drilled out to a depth of 300 feet bgs. If the well retrains open and stable, the interior of the casing will be investigated using a video camera and geophysical logs as described in the work plan. 2. The casing will then be perforated across an interval corresponding to the approximate depth of the Corcoran Clay,based upon the existing well driller's log. As discussed with the regulatory agencies, this interval will be between 225 and 300 feet bgs, unless otherwise indicated by the well investigation. The well will then be pressure grouted in one lift using Postnix®cement as described in the work plan. 3. If no obstructions are present and the well is open to it's total depth of about 608 feet,the well construction will be investigated using video camera and geophysical logs as described in the work plan. The well will be grouted in two lifts between 460 and 608 feet bgs and 0 and 460 feet bgs,unless otherwise indicated by the well investigation., We are currently planning on moving ahead with the demolition of AG-3 beggb ping on Wednesday, April 26, 1995, "Therefore, if you have any additions or alterations to our recommended procedures,please notify me or Jamie Atwood by Tuesday,April 25, 1995. Current operations are anticipated to require one to two weeks.