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i~- The permit area lies on the drainage divide between Trout Creek and Middle Creek as shown on Map 2 of this document. These are both perennial streams which flow in a northeasterly direction into the Yampa River. Trout Creek receives the drainage from the facilities area and forms the southwest boundary of the disturbed area. The drainage basin for Trout Creek above the mine includes an area of approximately 32.95 54uare miles. The runoff from the disturbed area of 5.6 acres constitutes less than 0.027% of the total flow of the stream. The runoff from the disturbed area is, therefore, insignificant to the flow of the stream. Surface water monitoring sites have been established both upstream and downstream of the mine on Trout Creek. Because of problems encountered with right-to-enter immediately downstream of the mine, Sunland Mining Corporation obtained permission to use monitoring information collected by the P8~1, Edna Mine, approximately one mile downstream. Comparisons of the nee year's worth of baseline for the two stations shows virtually no change in water quality or quantity between the two sites. Sufficient information was provided in the form of the P&14 monitoring and the monthly monitoring reports by Apex for the Division to make it's findings. During the review of the application, concerns were voiced about the facilities area being so. close to the stream. Sunland Mining Corporation hired Ginyery and Associates, a consulting firm, to provide an analysis of the flood potential for the disturbed area. The consultant's design confirmed that the facilities area was designed to minimize effects to the hydrologic balance. Even during a 100-year event, the facilities area will not be flooded. The area was elevated slightly to prevent potential flooding and the associated off-site affects of a flood. The narrowing of the flood plain resulting from the elevated facilities area will result in depth and velocity increases through the constriction during flood events. While the velocities will show increases of .up to 4 feet per second during flood stage through the constriction, these velocities are not unusually high for the stream in its natural highflow state. Erosion of the streambed will not be excessive because the stream flows through bedrock. In comparison, the constriction could possibly cause unusual erosion in two areas: the raised bench area and the streambank. The upstream end of the bench area has the greatest velocities in the constriction. The consultant's design called for rip-rap of a median size of 12-18 inches and a maximum slope of 2:1 alony the bank to protect against erosion. On-site inspections by both the consultant and the Division confine that the bench has been constructed in this manner. The effects of the constriction on land downstream are minimal. The depths and velocities ~aill be roughly the same as they would be without the constriction.The facilities area has been designed and constructed to minimize impacts to the hydrologic balance.