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respect to water rights. The scope of the review of water rights information for the first 5-year permit encompassed all areas to be affected during the second permit term, therefore, no additional review of water rights information will be required as part of the permit renewal process. The operation is in compliance with the requirements of this section. IX. Assessment of Probable Hydrological Consequences of Mining and Hydrologic Impacts - Rules 2.05.6(3) and 2.07.6(2)(c). A. Probable Hydrologic Consequences A discussion of the probable hydrologic consequences of mining has been provided in Volume I, Tab 7, Section VII.B of the permit renewal application. Surface Water The Seneca II Mine is located in the upper Yampa River basin on the north flank of the Williams Fork mountains. The mine is located on a watershed divide between the Fish Creek drainage basin to the east and the Grassy Creek drainage basin to the west. Most of the previous mining at the site has occurred in the Little Grassy Creek basin which is tributary to Grassy Creek, a perennial tributary to the Yampa River. Mining in the Fish Creek basin began in 1982 in the Cow Camp Creek tributary basin. As mining in this drainage approaches completion, an area in another tributary basin of Fish Creek, Bond Creek, will be disturbed. Mining activity will occur throughout the life-of-mine in this basin. The effects of mining on the water quality and quantity in each of these surface water basins is discussed below. Grassy Creek Drainage Basin Grassy Creek is a northerly flowing minor tributary of the Yampa River east of Hayden, Colorado. The Seneca II Mine is located about one mile upstream of the confluence with the Yampa River, and includes about 860 acres of disturbed lands within this drainage basin. Surface water monitoring sites are located above and below the mine to quantify mine-related impacts. Two ponds, NPDES 002 and 003, discharge between these two stations to Little Grassy Creek. The operator has conducted monitoring of discharge and water quality at the two surface sites in the Little Grassy Creek drainage since 1981. At the station above the mine (SW-S2-1) a mean discharge of 0.9 cubic feet per second (cfs) is characteristic of stream flow during the period June through September, the historic irrigation period in this portion of Routt County. A minimum flow of zero and maximum flow of 8 cfs has occurred during the period of record. A fairly constant TDS concentration of 570 mg/1 is observed during both high and low flows. Outflow from the Wadge Impoundment (NPDES 002) which, along with the Northwest Impoundment (NPDES 003), is located downstream of site SW-S2-1, is governed by three sources: 1, snowmelt runoff; 2. rainfall runoff; and, 3. -18-