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J ~ 7 sediment pond (Pond B) is designed to contain approximately 7 months accumulated sediment. The applicant has committed to semi-annual sediment cleanout of both sediment ponds, therefore the designs should be adequate. Sediment Ponds A and B are designed with emergency spillways capable of passing the peak flow from a 25-year 24-hour precipitation event. Neither sediment pond is equipped with a principal spillway. Instead, the applicant proposes to install a pumping system to dewater the sediment ponds and use the water in the hydraulic mining system. The sediment pond below the refuse embankment is not designed with a liner. Some type of lining is important since seepage from the refuse embankment will likely be highly saline. The Division finds that the following stipulation is necessary to ensure the minimization of impacts to the hydrologic balance: Stipulation No. 7 WITHIN 6 MONTHS OF PERMIT ISSUANCE, THE PERMITTEE MUST SUBMIT A PLAN TO THE DIVISION TO INSTALL OR CONSTRUCT A LINER IN THE SEDIMENT POND BELOW THE COAL PROCESSING WASTE EMBANKMENT THAT WILL MINIMIZE SEEPAGE LOSSES FROM THE SEDIMENT POND. THE PERMITTEE MUST OBTAIN DIVISION APPROVAL OF THIS PLAN WITHIN 9 MONTHS AFTER PERMIT ISSUANCE. Water Rights and Replacement The Storm King Mine is proposed as a hydraulic mining operation. As such, the operation requires large quantities of water for operations such as cutting of the coal use in slurry lines transporting fine refuse to the waste site. The operation has facilities designed to process and recirculate the majority of water required for the operation. The water circulation is designed as a closed-system with the major water loss occurring through evaporation, adhesion to coal and refuse, and by seepage underground during mining. The application projects that water loss through these processes will require a make-up of approximately 600 acre-feet of water annually to the system. The Storm King Mine has acquired water rights more than sufficient to augment their annual projected water loss. There is one drainage in the permit area which will be dammed by the refuse embankment. The refuse embankment is designed as a total containment structure for the probable maximum precipitation (PMP). The permittee has not submitted any application for water rights from this drainage. Therefore, the following stipulation is required. Stipulation No. 6 WITHIN 12 MONTHS OF PERMIT ISSUANCE, THE PERMITTEE WILL SUBMIT TO THE DIVISION A PLAN FOR REPLACEMENT OF WATER IF THERE IS A CALL ON THE DOWNSTREAM COLORADO RIVER SYSTEM, SUCH THAT ANY APPLICABLE WATER DERIVED FROM THE DRAINAGE IMPOUNDED BY THE REFUSE EMBANKMENT CAN BE RELEASED OR REPLACED. THE APPLICANT MUST ALSO ADDRESS IMPACTS TO THE HYDROLOGIC BALANCE IF SUCH AUGMENTATION IS NEEDED TO BE DERIVED FROM THE REFUSE IMPONDMENT.