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i • At or adjacent to the proposed mine site potential AVF's include alluvium associated with Watering Trough Gulch, Hubberson Gulch, and Dry Creek. The far east and west portions of the tie-across haulroad will cross alluvial deposits associated with Sage and Dry Creeks, respectively. Discussions in the text of the permit application, supported by data, indicate that Alluvial Valley Floors exist adjacent to, and, locally, within the permit area. All of the Gulches and drainages mentioned above contain creeks holding stream-laid deposits. There is potential for sub-irrigation, as documented by water level elevations from wells in Watering Trough and Hubberson Gulches. Depth to water measurements show that the water table in each drainage may vary from land surface to about seven feet below the surface. Flood irrigation is regionally practiced in areas similar to Hubberson Gulch, Watering Trough Gulch, Dry Creek and Sage Creek. Hubberson Gulch supplies enough water to flood irrigate approximately 188 acres during the growing season. Sage Creek supplies enough to support seven acres. Water quality samples indicate that, generally, these waters are marginal for irrigation. Analysis of water samples indicated high values of sulfate, magnesium, and total dissolved solids. The applicant states that the continued use of these waters during the growing season for flood irrigation could pose a long term salinity hazard to poorly drained soils. Portions of each of the above mentioned drainages meet the definition of an Alluvial Valley Floor as defined by the regulations. The Division finds that mining and mine related activities will not impair the prevailing hydrologic balance of and/or impart material damage to Alluvial Valley Floors in or adjacent to the permit area. Portions of the tie across haul road are located along areas of the Dry Creek Alluvial Valley Floor which are currently used for hayland. Approximately 2.3 acres of hayland will be taken out of production for the tie across haul road. This represents 0.2% of the landowner's farming unit. The Division finds that the amounts of land taken out of production by the tie across haul road to be an insignificant percentage of fanned land. The area will not be mined and will be reclaimed to re-establish pre-mining productivity. Actual mining activities will be conducted a half mile or more from the alluvial deposits of Hubberson Gulch and Dry Creek. The use of diversion and control structures will prevent damage to the prevailing hydrologic regime in each drainage. The Division finds that the applicant, through the use of culverts, drainage ditches, and sediment ponds, has designed the mine plan and tie-across haulroad to minimize impacts to the alluvial systems and prevailing hydrologic balance. The applicant is in compliance with the requirements of Section 2.06.8 -25-