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AVF Findint?s The Division has determined that an alluvial valley floor exists within the affected or adjacent area. Therefore, the following findings are in order for the alluvial valley floors known as Sage Creek, Hubberson Gulch, and Dry Creek located east, west, and northwest, respectively, of the permit boundary. 1. With regard to Dry Creek, the Division finds that activities proposed by the applicant will not interrupt, discontinue, or preclude farming on the alluvial valley floors that are irrigated or naturally subirrigated except for small areas which may provide negligible support for the farm's agricultural production (4.24.3(1)) and 2.06.8(5}(a}(i)). The only mining related activity which would interrupt farming on an alluvial valley floor is the tie across haul road which has already been completed. The Division previously determined that the 2.3 acres of hayland on the Dry Creek AVF which would be taken out of production represented only 0.2 % of the farm unit and was therefore of negligible impact. Actual mining operations will be conducted a half mile or more from the alluvial deposits of Hubberson Gulch, Dry Creek, and Sage Creek. 2. With regard to Hubberson Gulch, Sage Creek and Dry Creek, the activities will not materially damage the quantity or quality of water in the surface or ground water system (4.24.3(3) and 2.06.8(5)(a)(ii)), and the proposed activities will comply with the requirements of the Act and the Regulations with respect to alluvial valley floors (2.06.8(5)(a)(iii). a. On Hubberson Gulch, a 26 acre subirrigated and flood irrigated hayfield, and a point of diversion are located in portions of Sections 16 and 21, TSN, R88W. The fields are downstream from Pond 016 and 017 discharge points and upstream from the 006 Gulch confluence. This field is a small part of a much larger ranching operation. Hay production from this field contributes approximately 6 percent of the total ranching operations production. Mining in the Seneca II-W South Extension Area is projected to increase the salinity levels in Hubberson Gulch. TDS concentration of the irrigation water used on this field is estimated to be 1787 mg/I which equates to a specific conductance of approximately 2.4 millimhos/cm. In Tab 17, SCC presents an estimate of potential crop reductions based on the increased salinity level of irrigation water in Hubberson Gulch. SCC projects an estimated annual yield reduction of approximately 4.5 tons from the subject AVF fields, which corresponds to 0.6% of the total annual hay production for the ranching operation. This is considered to be a negligible impact pursuant to the Division's material damage guideline. Seneca II-W Findings Document 64 June 12, 2006 Permit Renewal No. 5