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permanent features. <br /> III Hydrologic Balance - Rule 4.05 <br /> A. Water Quality Standards and Effluent Limitations <br /> All discharges of water from the Yoast mine site from storm runoff and spoil springs will <br /> pass through a sediment pond designed to ensure that all discharges meet effluent limits <br /> in Seneca Coal Company's NPDES permit for the Yoast Mine. A storm water permit and <br /> Spill Prevention, Control and Countermeasure (SPCC) plan associated with the NPDES <br /> permit also dictate preventative and mitigation measures for ensuring that all water <br /> leaving the mine site meets applicable effluent limits. <br /> B. Diversions and Conveyance of Overland Flow <br /> Various collection ditches routed disturbed area runoff to treatment ponds during active <br /> mining. With the exception of road ditches collection ditches have been reclaimed. <br /> Permanent drainages have been reconstructed in mined areas to approximate the original <br /> drainage density. Reconstructed drainages are designed to safely pass runoff from the <br /> predicted 10-year, 24-hour precipitation event. Details of permanent drainage designs <br /> are located in Tab 13 and 20 of the permit application package. <br /> C. Sedimentation Ponds <br /> Sediment ponds to treat disturbed area runoff include Ponds 010, 011, 011A, 012, <br /> 013, and 014. Ponds 10, 13, 14, 11A have been designated permanent ponds. Ponds 11, and <br /> 12 are awaiting permanent designation from the State Engineers Office. <br /> D. Acid Forming and Toxic Forming Spoil <br /> A minor portion of the spoil (overburden, interburden) generated by the mining operation <br /> had the potential to be acid forming or toxic-forming. Seneca Property, LLC sampled <br /> regraded spoil material in areas of potential concern prior to replacement of topsoil to <br /> determine the presence of acid or toxic forming spoil material at the surface of regraded <br /> pits. Any areas with characteristics unsuitable for plant growth were treated chemically or <br /> buried with at least four feet of topsoil. The regraded areas were sampled as required, and <br /> no acid-forming or toxic-forming spoil was encountered on site. <br /> E. Surface and Ground Water Monitoring <br /> Seneca Property, LLC implemented a water monitoring plan to determine what, if any, <br /> impacts the operation would have on the prevailing hydrologic balance. The plan is <br /> described in Tab 15 of the permit application. <br /> 1. The applicant conducts monitoring of ground water and surface water as per DRMS <br /> regulations. The ground water monitoring plan is listed in Tables 15-3 and 15-4 <br /> and 15-4a of the permit document. (4.05.13(1)). The surface water monitoring <br /> plan was submitted under 2.05.6(3)(b)(iv) and is listed in Tables 15-2, 15-5 and <br /> 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 /> 11 <br />