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• -13- • Sediment and Runoff Control Details of the sediment control plan for the operation are provided in Section 2.05.3(4) of the permit application. Basically, the components of the plan consist of a sedimentation pond, a permanent diversion ditch, sediment collection ditches to route flow from disturbed areas into the sedimentation pond, and diversion ditches to conduct undisturbed flow around the disturbed area. The sediment pond has been approved under a compliance plan which was required by the Division. This plan was required to mitigate the effects of the existing disturbance at the mine site, The approved pond provides: 3) adequate capacity for the storage of runoff from the IO-year, 29-hour event (3.25 acre-feet); 2) sufficient capacity for a three-year accumulation of sediment (1.014 acre-feet); 3) an automatic dewatering device which wi12 dewater the pond within 72 hours of a storm event while providing a theoretical detention time of 29 hours; and 4) a spillway configuration which will be stable under the required conditions. The applicant has stated that sediment will be cleaned from the pond when accumulations of sediment reach 60e of sediment storage capacity. However, no provisions have been made for monitoring sediment storage to detez-mine when the 60~ level will be attained. For this reason, the Division z•equires the following stipulation: Stipulation No. 1: WITHIN 30 DAYS OF PERMIT ISSUANCE, THE PERlfITTEE SHALL INSTALL A SEDIMENT MARKER IN THE SEDIMENTATION POND WNICN WILL CLEARLY INDICATE THE 60~ SEDIMENT STORAGE LEVEL. Sundance Coal Company has not yet provided the inspection and certification report for construction of the sedimentation pond, which is required by Rule 9.05.6(7). Also, Sundance Coal Company must commit to submitting a quarterly inspection report for the sedimentation pond to comply with Rule 9.05.9(I1)(c). The following stipulation is, therefore, required: Stipulation No. 2: WITHIN 30 DRYS OF PERMIT ISSUANCE, THE PERAfITTEE MUST PROVIDE THE DIVISION WITH RN INSPECTION AND CONSTRUCTION REPORT WHICH ZS CERTIFIED BY A QUALIFIED REGISTERED PROFESSIONAL ENGINEER (RULE 4.05.6(7)). THE PERMITTEE 14IJST ALSO PROVIDE THE DIVISION WITH QUARTERLY INSPECTION REPORTS FOR THE POND. The permanent diversion ditch has also been approved under the aforementioned compliance p1 an. The structure will divert flow from Starkville Gulch above the disturbance, route flow around the disturbance, and will dischaz~ge below the sediment pond into Starkville Gulch. It has been demonstrated bey the applicant that the diversion ditch will be stable under the conditions of the 100-year, 24-hour storm event.