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Seneca II and Seneca II West coal mines. Only a minor portion of the spoil generated by <br /> the mining operation has the potential to be acid forming or toxic-forming. This is due to <br /> acid forming potential of a fraction of Wolf Creek overburden and low pH and high Boron <br /> found in and near the Lennox coal seam. Seneca Property, LLC previously committed to <br /> sampling regraded spoil material in areas of potential concern prior to replacement of <br /> topsoil to determine the presence of acid or toxic forming spoil material at the surface of <br /> regraded pits. Any areas with characteristics unsuitable for plant growth were to be treated <br /> chemically or buried with at least four feet of topsoil. The regraded areas were sampled as <br /> required, and no acid-forming or toxic-forming spoil was encountered on site. <br /> E. Surface and Ground Water Monitoring <br /> Seneca Property, LLC has devised a water monitoring plan that will enable the Division to <br /> determine what, if any, impacts the operation will have on the prevailing hydrologic <br /> balance. The plan is described in detail in Tab 15 of the permit application. <br /> 1. The applicant will conduct monitoring of ground water in a manner approved by <br /> the Division. The ground water monitoring plan is listed in Tables 15-3 and 15- <br /> 4 and 15-4a of the permit document. (4.05.13(1)). <br /> 2. The applicant will conduct monitoring of surface water in a manner approved by <br /> the Division. The monitoring plan was submitted under 2.05.6(3)(b)(iv) and is <br /> listed in Tables 15-2, 15-5 and 15-5a of the permit document. (4.05.13(2)). <br /> F. Probable Hydrologic Consequences <br /> Probable hydrologic consequences of the Yoast mining operations are discussed in Tab <br /> 17 of the permit application package. A summary of that discussion is presented below. <br /> Groundwater <br /> The probable hydrologic consequences to groundwater resulting from coal extraction at <br /> the Yoast Mine include drawdowns to aquifers from pit inflows, and subsequent pit <br /> dewatering and production well pumping as well as impacts to groundwater quality <br /> resulting from flow through mine spoil. As the Yoast Mine is now reclaimed, pit <br /> dewatering and production well pumping will not occur during the 2015-2020 permit <br /> term. Seneca's predictions of the magnitude of these impacts are discussed below. <br /> Groundwater Inflows to Pits and Associated Drawdowns <br /> The Yoast Mine intercepted the following hydrologic units: the Wadge Overburden, <br /> Wadge Coal, Wolf Creek Overburden, and Wolf Creek Coal. Seneca Property, LLC used <br /> two models to predict pit inflows as a result of mining activities. The models were the <br /> McWhorter (1982) method and the Theis equation, both of which are described in detail in <br /> Tab 17 of the PAP. The Theis equation, which was also used to predict drawdowns, <br /> consistently predicted higher discharges for each aquifer with the exception of the Wolf <br /> Creek Coal than did the McWhorter method. <br /> The more conservative estimates of pit inflows from each aquifer in cubic feet per day <br /> were 365 for the Wadge Overburden, 160 for the Wadge Coal, and 745 for the Wolf <br /> Creek Overburden, and 499 for the Wolf Creek Coal. Variability in aquifer characteristics <br /> 16 <br />