2014-05-28_REVISION - C1996083 - Laserfiche WebLink

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William A. Bear Page 2 of 8 May 28, 2014 With the approval of PR -11 the Division accepted the demonstration of the hydrologic separation of the Rollins Sandstone from the effects of mining operations and, as a result, concluded that BRL would not be obliged to install deep down - gradient wells to monitor this member. With the approval of PR -12, up- gradient (CWI -DH -58 and -60) and down - gradient (2010 -113 and -1SS) monitoring wells were incorporated into the PAP and the monitoring plan to monitor the B -Seam and the sandstone above the B -Seam in the western mine plan area. A recommendation was made by the Division to incorporate mine inflow monitoring and sampling to substantiate the observations made at the up- gradient wells. With PR -13, BRL demonstrated the continued separation of the Rollins Sandstone from the area to be mined in the western mine plan area, preventing the need for a down - gradient point of compliance in the Rollins. The Division also approved BRL to mine through 2010 -1B and -1SS, in 2015. Furthermore, the Division found that BRL would not be required to replace the down - gradient monitoring wells, accepting the reasons (expense and technical difficulty) and the justifications (that down - gradient groundwater is not likely to be put to beneficial use because of: poor ambient water quality, the prohibitive cost of installing a well to sufficient depth, and the difficulty in obtaining USFS approval for the installation of a deep bedrock well; and that the distance to the nearest private landowner ( -4 miles) is sufficient to attenuate the effects of BRL's activity on groundwater quality). Wasatch formation, up to 1600' thick (Eocene) Ohio Creek formation, 0 -200' thick (Paleocene) Barren Sandstone member Mesaverde formation, 2300' thick (Cretaceous) F -seam Upper and Lower Coal members B, C, D, E -seams A -seam Rollins Sandstone member Mancos Shale Figure 1: Generalized stratigraphy at the Bowie 2 mine With PR -14, BRL proposes to expand the western extremity of its mine plan to the north, so that eight additional longwall panels of B -seam coal may be mined. BRL does not propose to replace 2010 -1B and 2010 -1SS with new wells further to the north. The assumption underlying the argument made by BRL with PR -13 is that the scope of the monitoring program need only encompass groundwater that is likely to be put to beneficial use, however the rules do not make such a distinction. If PR -14 were to be approved as proposed, the subsequent scope of the groundwater monitoring program would be extremely limited. Figure 2 is an image showing the position of active groundwater monitoring points, overlaid on the western part of the proposed mine plan, (the hydraulic gradient is approximately from south to north). Six points are shown and are relevant to this discussion. They are listed in Table 1 from south to north.