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Joe Dudash <br />September 22, 2008 <br />Page 2 <br />conclusion is that there are probably no permitted wells utilizing bedrock groundwater down <br />gradient from the mining operation. Although the groundwater is probably not used for <br />domestic or agriculture uses at this time, it is still considered potentially useable since TDS <br />levels are less than 10,000 mg/l. For unclassified groundwater areas, the applicable standards <br />are the Interim Narrative Standards from Reg. 41. <br />My position on this matter has not changed since my memorandums of July 25 and July 28 to <br />you regarding groundwater issues and Permit Revision No. 10 at the Bowie No. 2 Mine. I do <br />not believe that the information provided is adequate to satisfy our minimum requirements <br />for Ground Water Information per Rule 2.04.7 Hydrology Description. In accordance with <br />2.04.7, the operator shall provide the seasonal quantity and quality of the water in each <br />aquifer for the permit and adjacent area. There is a general lack of data to satisfy our <br />minimum baseline data requirements and given the proposed plan there would be disturbance <br />beyond the limit of the current down gradient monitoring locations. My recommendation is <br />that we require BRL to provide better characterization of the upper and lower perched <br />aquifers that are described in the permit. As discussed below under Item 2C, the question <br />regarding the Rollins Sandstone has been successfully resolved. <br />Additional down gradient monitoring wells should be required for the perched water zones <br />and the B coal seam at or beyond the limit of proposed disturbance associated with PR-10 <br />(and will also be necessary for the PR-11 extension). Ideally these wells should be installed <br />and monitored ahead of time so that we can establish seasonal baseline characterization of <br />the perched water zones at the northern end of the permit boundary before they are <br />potentially disturbed. The perched water zones are described by BRL as (above the D- <br />Seam), and (below the D-Seam and above the B-Seam). The Upper and Lower Perched <br />Water Zones should be shown in cross-section and BRL should provide the Division with a <br />plan for our approval to install additional monitoring wells that will adequately characterize <br />and provide monitoring for these zones and the B-Seam coal at or beyond the limit of <br />disturbance proposed with PR-10 (and will also be necessary for the PR-11 extension). <br />2B. No response required. Please note that BRL has not proposed a plan for determining the <br />need or location for a point of compliance well in the alluvial aquifer. <br />2C. Response accepted. BRL updated the Geologic Cross-Section as requested and has <br />demonstrated that the Rollins Sandstone should not be impacted by the mining operation. <br />2D. Response accepted. <br />c: Sandy Brown <br />Denver File