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c. Background salinity levels in the lower segment of Dry Creek from the Yampa River upstream to Section 28, Township 6 North, Range 88 West are high enough that no degradation of water quality is anticipated due to mining. Agricultural areas potentially impacted by increased salinity levels include two small subirrigated grass hayfields in Section 9, TSN, R88W and flood irrigated grass and alfalfa haylands in Section 28, T6N, R88W. With respect to the flood irrigated fields in Section 28, the application indicates and includes detailed mapping and aerial photographs which show that the subject fields are irrigated by water from J.C. Temple Reservoir #1, not from Dry Creek. Thus, water supplying the irrigated fields would not be affected by the mining operation. With respect to the subirrigated fields in Section 9, the applicant conducted a detailed evaluation of the potential reduction in crop production resulting from the projected increase in salinity of the alluvial water. The material damage evaluation is presented on pages 47 and 48 of Tab 17. The evaluation projects a potential production decline of 1.9%, which is considered to be a negligible impact, pursuant to the Division's material damage guidelines. There is no projected diminution of water quantity supplied to the Dry Creek AVF. 3) Surface coal mining and reclamation operations will be conducted to preserve the essential hydrologic functions of alluvial valley floors outside the permit area and to reestablish the essential hydrologic functions of alluvial valley floors within the affected area throughout the mining and reclamation process (4.24.2). An environmental monitoring system as described in Tab 15 of the permit application has been installed, maintained, and operated by the permittee on all alluvial valley floors during surface coal mining and reclamation operations and continued until all bonds are released in accordance with Rule 3 (4.24.4). Plans and commitments contained in Tabs 15 through 18, and Tab 22, adequately address those measures which will be taken to monitor potential impacts and insure that the essential hydrologic functions of alluvial valley floors within the permit area are reestablished after mining and that the essential hydrologic functions of alluvial valley floors outside the permit area are preserved during and after mining. if future monitoring of affected surface and ground waters indicates trends which necessitate alteration of the projections upon which these AVF findings are based, the findings will be reevaluated and modified as appropriate. 41