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seam and overlying Barren Member in areas of shallow overburden. <br /> This is secondary permeability and is the result of groundwater flow <br /> through the fractured and weathered portions of these strata. The <br /> fractured rock acts as a conduit to the surface colluvial aquifers. The <br /> third type of inflow is also due to secondary permeability and it is the <br /> result of groundwater flow along fault zones. These fault zones may be <br /> in contact with surface aquifers with water bearing zones in the <br /> overburden, or with deep-seated sources of groundwater. The streams <br /> in the North Fork area are generally fault controlled and may be a <br /> source of recharge for fault related inflows. Prior to the construction of <br /> the mine entries, piezometers were installed in the colluvial/landslide <br /> strata immediately upslope of the entries. All piezometers but one were <br /> destroyed during construction of the entries. <br /> The operator at the West Elk Mine expects that mine inflows will <br /> increase at a rate slower than the McWhorter model predicted for <br /> advancing mine workings. Most of the inflow has occurred along the <br /> subcrop in the same location each year. The inflow is seasonal and <br /> varies with the magnitude of seasonal precipitation. The experience <br /> near the F Seam subcrop and in the Mayo report indicates that the <br /> colluvium, coal and bedrock are recharged locally. In prior years, <br /> inflow to the advancing mine workings has been minimal and <br /> unmeasurable. However, In March 1996, MCC experienced a large <br /> inflow of water in the B East Mains while mining through a <br /> fault/fracture system. In April 1996, MCC encountered the same fault <br /> in a subsequent entry, the inflow was estimated to be a maximum of <br /> 2,500 gpm. The flows have since receded. In May 1996, the flow was <br /> measured at approximately 240 gpm and had diminished to less than <br /> 100 gpm by December 1998. <br /> Three of the five entries experienced inflows during construction, <br /> which began in September of 1981. Adit entry No. 4 experienced the <br /> greatest inflow, about 5 gpm, which decreased to less than 1 gpm and <br /> dried up within a week. The No. 1 entry produced a small quantity of <br /> water from the bottom of the coal at a rate of less than 1 gpm and dried <br /> up within two weeks. However, the sandstone roof at entry No. 1 was <br /> dry. Entry No. 5 produced drips, approximately 0.1 gpm, for about <br /> one week. The other two entries were dry. During the period from <br /> August to December 1981 water levels dropped in some of the <br /> piezometers located above the portals. In all cases the drop was not <br /> greater than two feet. Water levels have changed very little since <br /> January 1982. <br /> MCC has submitted two plans for the sealing of the portals upon <br /> closure of the mine. The first plan calls for sealing the portals to allow <br /> gravity discharge of mine inflows. MCC anticipated, from water <br /> 37 <br />