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7Vfs. Erica Crosby March 3Q, 2007 Page 9 resulted in significant inflow developing along the north and/or eastern highwall. Further, ice has been observed along the highwall in this general area, suggesting that some flow could be coming out of the shale formation adjacent to C-Pit. The specific method of testing this line (e.g. air testing, etc.) will be developed in collaboration with CEMEX plant staff. The testing will be performed during the next scheduled plant shut down, presently estimated to be in July 2007. Task 6.0 Data Management, Analysis, and Reporting All field and laboratory analytical data from the program outlined ui the preceding tasks will be compiled and summarized in a report to be submitted to the Division. Data management and analysis activities will include such things as: 1) downloading, compiling, and converting pressure head data from the data loggers to mean sea level elevation data; 2) tabulation of chemistry data and comparison with the data from C-Pit and existing well CEM-001; 3) development of correlation plots of water level data with that from the C-Pit and well CEM-001 monitors, preparation of a map showing potentiometric data in the area; and 4) plotting of relevant chemical data (e.g. trilinear diagrams) to aid in understanding water chemistry relationships. The data from this Hrst phase of work will be used to xefine our current conceptual model fox the C-Pit area, which will be used as the basis for a proposed long-term monitoring program for C-Pit, The proposed monitoring plan will include the locations and frequency of water level monitoring, locations and frequency of sample collection for laboratory analysis, and the analytical parameter suite fox the various monitoring locations. -~ SCHEDULE Due to the approaching irrigation season, we recommend that the piezometers are in place by mid-April, in time to monitor any influence due to water flows in the Boulder Feeder Canal and the Swede Ditch, We are hopeful that the Division will be timely in your review of the proposed TR-8 plan outlined in this letter. Assuming that the field program can commence by mid-April and the ditches can be successfully gauged by mid-May, we anticipate that a report can be issued to DBMS no later than July 1, 2007. CONTINGENCY: C-PIT FILLING PROGRAM As DRMS is aware, CEMEX is presently filling in C-Pit with inert fill material from borrow sites on the Lyons [nine permit. The monitors installed in C-Pit and at well CEM-001 provide water level information and basic chemistry data that can be downloaded and reviewed as the ftlling progresses. As expected, the water level in C-Pit is rising as the water is displaced by the fill. Although we are confident that we have mobilized sufficient earth moving equipment to meet the May 17, 2007 deadline to have the water surface eliminated, CEMEX requests permission from DBMS to use bixdballs or netting as a temporary mitigation measure if it is determined that the water level rise is excessive. We think it is likely that any water level rise/mounding at C-Pit will be followed by a return to an -059468G.doc