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<br />The mine is presently incurring water sources in both the north and south <br />sections of the mine, quantification of total depletions to Newlin Creek <br />are nearly impossible to make, since mining adjacent to this creek was <br />primarily done from 1900 through the 1970'5. Most of these areas have <br />been sealed off and, therefore, could not indicate reliable inflows. <br />However, the mine inflow study being conducted by the operator will <br />provide valuable data on impacts from the Southfield operation. The <br />primary source of water entering the mine appears to be abandoned <br />workings nearby and above the mine. Quantities of mine inflows have <br />decreased by nearly 50% over the past four years. <br />B. Surface Water Description <br />The permit area and proposed expansion are dissected by three major <br />drainages: Newlin Creek (a perennial stream), Magpie Creek and <br />Second Alkali Creek (both of which are ephemeral streams) The streams <br />flow to the northeast of the permit area where they empty into <br />Hardscrabble and Coal Creeks. Hardscrabble Creek is an ephemeral stream <br />while Coal Creek is perennial. These two drainages discharge into the <br />Arkansas River which is the major perennial drainage in the area. <br />The base flow of Newlin Creek is diverted by the City of Florence <br />upstream from the Southfield permit area. This water is carried across <br />the permit area by a 12" pipeline. EFCI has monitored both the <br />Newlin Creek streambed and the Florence pipeline for subsidence since <br />1984. During the following four years of monitoring, maximum vertical <br />changes for the Newlin Creek streambed and the Florence pipeline were <br />0.6 feet and less than 0.1 feet, respectively. <br />The Magpie Creek drainage was diverted around the mine facilities area by <br />Dorchester in 1982. The drainage and diversion are discussed in <br />Section XVI of this document. Upon completion of mining, the <br />Magpie Creek drainage will be re-established in its approximate original <br />configuration. <br />Monitoring of Magpie Creek to date has consisted of flow measurements on <br />sampling days once each quarter. Peak flows in Magpie Creek need to be <br />measured to provide data for reconstruction of the channel after mining. <br />Therefore, the following stipulation is included here. <br />Stipulation No. 14 <br />ALL PEAK FLOWS SHALL BE MEASURED IN MAGPIE CREEK AT THE CURRENT <br />MONITORING STATION. DATA ACQUIRED FROM THIS MONITORING SHALL BE <br />SUBMITTED QUARTERLY AND INCLUDED IN THE ANNUAL HYDROLOGY REPORTS FOR THE <br />MINE. <br />Second Alkali Creek is an ephemeral drainage which crosses the northern <br />end of the proposed permit area expansion. Since there will be no <br />surface disturbance in this area other than possible subsidence, the mine <br />is not expected to affect Second Alkali Creek. <br />-15- <br />