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SCCC Response: A new map titled Map 2.04.13-M3, Permit and Regulatory Information Map <br />has been included in the revised PSCM PAP to address items a) through g) above. The map is <br />referenced in the Annual Reclamation Report section of the PAP text beginning on page 2.04- <br />174 (section 2.04.13). Text, exhibits and maps supporting responses to comments 16 and 25 <br />provide additional or more detailed information for several of the above requested items. All <br />new and revised materials are included in the PAP revision package. <br />9. Page 2.05-77 proposes to discontinue ground water monitoring in underburden, citing a <br />lack of hydraulic communication with mine workings. Please add a few statements <br />discussing the potential for ground water from the Trout Creek Sandstone to enter the <br />PSCM workings from an unexpected fault as it has been suspected of doing in the 2 West <br />Main of the #5 Mine of the Eagle Mines in Moffat County (permit page 2.05-37, Eagle <br />Mines, Permit C-81-044). <br />SCCC Response: A discussion of an unexpected fault's potential impact on the PSCM <br />workings has been incorporated in the subject text section, now located on page 2.05-78 of <br />section 2.05.6(3)(b)(iii). <br />10. Please either explain the rationale for grouping constant head data with the slug data in <br />Table 2.04.7-T2 and then calculating a geometric mean, or exclude constant head data <br />from the calculation of means in the table. The Division is concerned that grouping the <br />constant head data with the slug test data is not valid, based on the probable much greater <br />accuracy of constant head data compared to slug test data. <br />SCCC Response: Based on the slug test data falling within the regional data envelope (see <br />Comment 12. response below), SCCC believes the slug test data is representative of <br />hydrologic conditions at the mine. The use of slug test data together with constant head <br />data results in a tendency to overestimate rather than underestimate the probable <br />hydrologic consequences of the proposed mining. This is believed to offer a more <br />conservative and therefore appropriate approach to the analysis. <br />11. Please add to the text more detailed description of the aquifer test methods (for example: <br />isolation of test intervals in holes, hole/casing diameters in test intervals, slug volumes, <br />slug lengths compared to assumed saturated zone thicknesses, water level measurement <br />time periods, relative reliability of constant head data compared to slug test data). <br />SCCC Response: A detailed discussion of aquifer test methods is presented beginning on page <br />2.04-47 of section 2.04.7. The discussion includes field methods and the analytical <br />solution used to solve for aquifer parameters. <br />12. Please add a discussion of how the hydraulic conductivity and transmissivity values <br />obtained in SCCC's wells compare to the regional values reported by Robson and <br />Stewart (1990) for slug tests and pump tests in wells drilled to depths similar to SCCC's <br />wells. <br />SCCC Response: A discussion addressing the comment has been incorporated into the text <br />starting on page 2.04-49 of section 2.04.7. In addition, Figure 2.04.7-F7.1 and Figure <br />2.04.7-F7.2 present graphical representations of other researchers' aquifer parameters <br />3