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§2.05 APPLICATION FOR PERMIT FOR SURFACE OR UNDERGROUND MINING 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.) Enclosed coal handling facilities and the general cleanliness of the areas further prevent detrimental contact with groundwater sources. Groundwater is monitored at the Bowie No. 1 Mine area, the West Mine area, and at the coal stockpile/truck dump/train loadout area. Boreholes B-1 through B-7 were installed in the fall of 1981, and borehole B-B was installed in 1982 to ascertain the stability conditions of the fills and the proposed waste disposal sites at the Orchard Valley Mine. Refer to the Phase II and Phase III Geotechnical Studies in Volumes 6 and 6A for further discussion regarding the installation and initial data obtained from the boreholes. Though these boreholes were not drilled as part of the groundwater monitoring program, some hydrology data is obtained from the boreholes. Boreholes in the vicinity of the Bowie No. 1 Mine are currently monitored when accessible in accordance with the requirements of Volume 4, Table 9B. Boreholes B-1 and B-2 are located at the East mine fan level. These holes have been dry since they were installed. Borehole B-3 is located at the east end of the crushing and screening level. This borehole typically exhibited approximately 6 feet of water at the bottom of the hole thought to originate from colluvial seepage. The casing for borehole B-3 failed at depth in the spring of 1988 and no water has been detected since. B-3 was originally drilled to a total depth of 89 feet and now measures approximately 73 feet. Boreholes B-4 and B-5 are located below the crushing and screening fill and were installed to detect possible seepage in the original grade material. B-9 typically has 15 feet of water present at the bottom of the hole and B-5 is dry. Borehole B-6 is located upslope of the reclaimed waste disposal pile and is monitored for interface seepage in connection with slope and waste pile stability. Borehole B-6 is dry. Borehole B-7, also referred to as Node 22, is located below sedimentation pond #4 and is periodically monitored for water quality to ascertain potential groundwater contamination attributable to the East Mine facilities area. Parameters measured include alkalinity as CaC03, bicarbonate as CaC03, carbonate as CaC03, dissolved calcium, chloride, conductivity @ 25° C, pH, Hardness as CaC03, dissolved magnesium, dissolved sodium, sulfate, TDS ratio (gray./calc.) and total dissolved solids. Borehole B-8 is located below the West Ridge Waste Pile sedimentation pond and monitors subsurface groundwater flow fYOm the sedimentation pond. Borehole B-8 is dry. One piezometer (OVWM) is installed in the fill at the West Mine. This well is currently monitored when accessible for water levels to evaluate fill stability in accordance with the requirements of Volume 4, Table 9B. Revised 12/10/93 />12-I O $' Revised 9/21/01 /jpPRovE9 115 G/> 4 /0 y