2008-08-01_REVISION - C1996083 (3)

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75ii is acceptable, but should be backed up with drill log information and cross-section(s) illustrating that subsurface conditions should prevent integration of water from either the D-Seam or B-Seam into the underlying Rollins Sandstone. The geologic log for drill hole G15 that is referenced in BRL's revised page 2.05-75ii should be incorporated into the PAP and correlated with and updated in appropriate cross-sections. D. With PR-10 and PR-11, BRL proposes to extend the permit boundary northwards. In accordance with 2.04.6, geologic maps and cross-sections should be updated for the entire permit area. Likewise in accordance with 2.04.7(4) (c), the location and extent of sub- surface water, if encountered, within the proposed permit and adjacent areas should also be updated if available. Please update Maps 7 and 8 Geology and Geologic Cross-Section and Maps 10 and 11 Upper and Lower Perched Water Zone Mesa Verde Formation, respectively. 3. Because future mining will be extending northward past the current upgradient stream monitoring locations on Hubbard Creek and Terror Creek, please propose new upgradient stream monitoring locations for these two streams. The new locations should be upgradient of all proposed mining. For these new upgradient water monitoring locations, baseline water monitoring, similar to that performed for the current stream stations, will be needed, per Rule 2.04.7. Also, please revise the permit text and maps where appropriate. The Division has no further concerns. BRL responded that surface water monitoring stations D34- 14 and D32-4 are up gradient of the proposed mine workings,. In an e-mail dated February 22, 2007, the Division requested that flow measurements be made during the winter and early spring months of 2007 at these two sites to complete baseline monitoring. In the submittal dated January 30, 2008, BRL stated that they asked the USGS to monitor flow at the two stations in the winter. March 2007 data has been recorded and is listed in the January 30, 2008 cover letter. The fall 2007 flow data is listed in the 2007 AHR. 4. Rule 2.04.7(3) requires alternate water supply information if contamination, diminution or interruption of a surface water source may result from the effects of mining. Since mining effects could damage the main and saddle dams of the Terror Creek Reservoir, as stated in Section 2.05.6(6)(b)(i)(C) of the revised permit text, please revise this section of the permit text to include an appropriate discussion concerning the Terror Creek Reservoir. The Division has no further concerns. BRL initially responded in the December 28, 2006 cover letter that, based on their subsidence and seismicity studies, they were revising the statement of the worst possible consequences in Section 2.05.6(6)(b)(i)(C) to state that the Bruce Park (Terror Creek) Reservoir and dam should not be affected by mining operations and, therefore, alternate water supply information under Rule 2.04.7(3) was not needed. However, based on information from the Division of Water Resources, the Division was concerned about the possibility that mine induced seismicity could cause the Bruce Park landslide to slide into the Terror Creek Reservoir. Therefore, the Division requested that BRL revise the permit text in Sections 2.05.6(6) and 2.04.7(3) to reflect this worst possible consequence. The submittal dated June 25, 2008 contained an appropriately revised subsidence information section