2010-06-15_REVISION - C1981038 (5)

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2.05 APPLICATION FOR PERMIT FOR SURFACE OR UNDERGROUND ACTIVITIES -- MINIMUM REQUIREMENTS FOR OPERATION AND RECLAMATION PLANS. 2.05.6 Mitigation of Surface Coal Mining Operation Impacts. (Cont'd.) (3) (b) (iii) (Cont'd.) of monthly water level measurements in drill holes 58, 60, 65, 69, 70, and GR-77. Water quality samples were monitored for field parameters monthly and lab analysis quarterly. The data obtained and conclusions from the interpretation were submitted to the Division in the "Annual Hydrology and Subsidence Reports". One federally-owned drill hole, GR-77, was included in the groundwater monitoring network. This drill hole was completed by the U.S.G.S. in 1977 in the central part of the East Roatcap Creek drainage. This well monitors the perched aquifer in the sandstone strata above the mine coal seam. The possibility of communication between this perched aquifer and the shallower alluvial/colluvial deposits overlying it exists. Water level in this well fluctuates between 123 and 133 feet from the ground surface and water quality is typical for shallow aquifers. This hole was monitored for depth and samples. DH-58, located in the SE/4 NW/4 Sec. 18, T13S, R91 W, of the 6th P.M., was drilled to a total depth of 1963 feet. This monitoring well, which has remained dry, was also monitored as part of the subsidence monitoring network. DH-60 was drilled to a total depth of 1350 feet. This monitoring well is located in the NE/4NE/4 Sec. 14, T13S, R92W, of the 6th P.M.. DH-65 is located in the NW/4NE/4 Sec. 15, T1 3S, R92W, of the 6th P.M. The total depth of this well is 1655 feet. DH-69 is located in the NE/4NW/4 Sec. 7, T13S., R91W, of the 6th P.M. This monitoring well is drilled to a total depth of 1975 feet. DH-70, located in the NW/4 SW/4 Sec. 17, T1 3S, R91 W, of the 6th P.M., was drilled to a total depth of 692 feet. The initial water level was measured at 534 ft. DH-70 was also monitored as part of the subsidence monitoring network. DH-70 was monitored for quality and depth. Responsibility for DH-58 and DH-69 will be transferred to the Bowie No. 2 Mine by PR-04 since the wells will reside within the new Bowie No. 2 Mine permit boundary. See Volume 4, Map No. 4-1 for the locations of all deep bedrock groundwater monitoring wells, Tables 4-A and 4-B for well completion summaries, and Tables 7 and 10 in Volume 10 for lithologies. Water quality data was obtained during the drilling of these drill holes from some random sampling. Enough data was gathered to characterize to deep bedrock water. CWI identified a number of alluvial/colluvial deposits as described in 2.04.7 (1). Only a few of the smallest deposits were scheduled to be undermined during the initial permit term. To gatherfurther information on the deposits, CWI constructed additional shallow PR-04 - 121 - 06/10