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Grassy Creek Basin Dischazges in the Grassy Creek basin aze seasonal, with the higher streamflows resulting from snowmelt runoff. Seneca Coal Company currently monitors three surface water sites in the Grassy Creek basin and two sites in the Little Grassy Creek drainage. Surface water site S W-S2-5, located in the southwest portion of the permit area and the Wadge Impoundment (NPDES Dischazge Point 002) are within the Little Grassy Creek Basin. Surface Water Site SW-S2-l, upstream on Grassy Creek, NPDES Discharge Point 003 and Surface Water Site SW-S2-2 aze within the Grassy Creek basin. Surface Water Site SW-S2-2 is the furthest downstream surface site in the Little Grassy and Grassy Creek drainages prior to exiting the permit azea, therefore, it is the most significant monitoring site with respect to showing the cumulative effects of mining in this azea. Fish Creek Basin Seneca Coal Company currently monitors seven surface water sites in the Fish Creek basin. NPDES 004 and Sites 6 and 10 aze located on Cow Camp Creek. NPDES 008 and site 12 aze located on Bond Creek. Sites 11 and 13 exist on Fish Creek. Stream site 6 was originally established to determine the premining characteristics of Cow Camp Creek. During this permit renewal, monitoring site 6 has been discontinued to eliminate redundancy with stream site 10 further downstream at its confluence with Fish Creek. Instantaneous flow measurements aze collected at all three creeks. Like the Grassy Creek drainage, streamflows in the Fish Creek basin aze seasonally vaziable with peak flows occurring in the spring in response to snowmelt runoff. F. Probable Hydrologic Consequences A determination of the probable hydrologic consequences of the mining and reclamation activities at the Seneca II Mine site has been made by the applicant and is found in Volume 4, Tab 7, Section VII.B of the permit application. This section includes an evaluation of quantity and quality effects on ground and surface water systems and mitigative measures to be taken both during and after mining. The Probable Hydrologic Consequences section of this document is divided into two main subsections; Surface Water Effects and Ground Water Effects. Surface Water Effects 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. 21