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The staff is concerned that there is no bedrock groundwater monitoring at <br />the Bear Mine. The Division is required to have baseline water quality <br />data to assess pre-mining conditions of aquifers at the site per <br />2.04.5(1) and 2.04.7(1). In addition the Division uses this information <br />in conjunction with the operator's assessment of probable hydrologic <br />consequences to prepare a cumulative hydrologic impact assessment. <br />Therefore the Division respectfully requests Bear Coal Company to do the <br />following: <br />a. Please compile sift-specific documentation on the permeability of <br />the overlying seams, the B seam and the underlying Rollins <br />Sandstone to demonstrate that there are no aquifers within the <br />permit area. If such information is not available please prepare a <br />schedule for running tests which will provide such information. <br />Describe the number of tests which will be run, the method of <br />testing, and the criteria which will be used to identify an aquifer. <br />b. If appropriate, based on the results acquired above, propose a <br />hydrologic monitoring plan which will provide information on <br />baseline water quality and quantity conditions in the aquifers of <br />interest and information which would identify potential impacts, <br />should they occur. <br />c. Prepare a quantitative probable hydrologic consequences section. <br />Include a discussion which addresses the impacts due to underground <br />mining or the quantity and quality of water in surface and ground <br />water systems under all seasonal conditions per 2.05.6(3)(bl(iv). <br />Include impacts associated with subsidence, a discussion of mine <br />water inflows and cones of depression if appropriate. <br />26. Bear Mine #3 Alluvial Well Salinities <br />The Division required Bear Coal Company to replace alluvial well AA-1 <br />because it appeared that the well had been contaminated following an <br />incident in which the well was purged with water from the sediment pond. <br />Conductivities of water in the pre-89 AA-1 had been recorded at levels <br />between 900 and 2250 umhos/cm following the 1986 purging incident and it <br />was a sodium sulfate water, Prior to that, conductivities ranged between <br />300 and 600 umhos/cm, and it was a sodium bicarbonate water. During the <br />September, 1989, inspection, Cathy Begej and Craig Springer checked the <br />conductivity in the newly installed well, and it also registered a <br />comparably high and potentially contaminated salinity level. <br />Data collected at alluvial sites along the south side of the North Fork <br />historically have had to tai dissolved solids levels less than 1000 mg/1. <br />ARCO has record of an alluvial sample obtained 6/19/78 at AL-1 of a <br />sodium bicarbonate water with a TDS of 520 mg/l. Bear acquired data from <br />the shop, east and west alluvial wells at Mines 1 and 2, Shop well TDS <br />levels ranged from 178 mg/1 to 562 mg/1 and the east well TOS levels <br />ranged from 190 mg/1 to 746 mg/l. On the other hand, the west well had <br />TOS levels ranging from 290 mg/1 to 3924 mg/1. Please account for the <br />higher salinities found in the alluvium on the western edges of the <br />disturbed sites. <br />-9- <br />