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~,.ater is encountered in the operation, the applicant should specify the monitoring methods, frequency, and parameters to be analyzed for. Para- meters should be determined in consultation with the Division. Also, water quality analyses for the alluvial wells should include all those parameters as required by the Division (See Appendix A). 3. The applicant should identify the potentiometric surface of any known aquifers in the area, along with known uses of water in the aquifers (including discharge/pumping rates). The potentiometric surface of each aquifer should be clearly depicted on an appropriate map. This includes the Cameo Coal Seam, which is unclearly depicted on Figure 4.9-1. If any aquifers are noted to occur above the coal seam to be mined, provisions must be made for monitoring them. 9. According to Figure 2.3-5, there is only one ground water monitoring station (G-1) depicted on Salt Creek. On page 4-16 of the text, it is stated that "...a total of six monitoring wells were installed (Figure 4.2-2)." Figure 9.2-2 has no legend and it is difficult to determine which of the holes listed are the monitoring stations. Therefore, the applicant should clearly show, on an updated map, where the ground water monitoring stations on Salt Creek are located. 5. A11 drill logs submitted in the application are for drillholes that were dry. The Division requests all additional drill logs, particularly for holes where ground water was encountered. 6. Figure 9.4-1 depicts the ,potentfematsic surface for the Cameo Coal Seam; however, all data concerning water levels are obtained from exploration boreholes. Boreholes are open the entire length of the drillhole to receive inflow of ground waters from all ground water producing zones. Therefore, water levels monitored in the drill holes may not be representative of the potentiometric surface for the Cameo ground water system. Rather, the water levels observed are more likely influenced by water producing zones above the Cameo seam. Sheridan Enterprises must discuss the adequacy of water level information submitted thus far. If sufficient rationale is not provided, the applicant will likely have to case the boreholes so specific zones can be monitored (such as the Cameo Coal Seam) in order to adequately define the ground water system. 7. Several perched water zones were also identified by the applicant. All geophysical logs submitted thus Far indicate that the boreholes extend down to the coal seam. It is our understanding that during drilling the first water producing zone can be reasonably located (if drilling is done with air). Deeper water producing zones (where an upper saturated zone was encountered) can only be detected by the driller if significantly more water is encountered. Therefore, the Division requests an explanation of how the upper perched zones were located and how they distinguished from other saturated zones if more than one water producing zone was encountered in the same hole. The locations of the perched zones should be specified and a determination must be made if the "perched" zones can be correlated to determine their areal extent. 8. The Division also requests an explanation of how boreholes were determined to be dry, particularly when the resistivity logs were measured for the hole. (3)