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The alluvial body at the confluence of Foidel Creek and Middle Creek, extending from the County Road No. 33 crossing of Middle Creek upstream on both Foidel and Middle to the first Trout Creek irsigation diversion as depicted on Foidel Creek Life-of--Mine Application Map No. 15, does meet alluvial valley floor criteria based upon existing flood irrigation and a presumed capability to support sub-irrigated vegetation. The required findings for the identified alluvial valley floor at the confluence of Foidel Creek and Middle Creek are set forth below. Alluvial valley floor findings for areas further upstream on Middle Creek aze addressed separately, under "Upper Middle Creek." The proposed mining operations would not interrupt, discontinue or preclude farming on the alluvial valley floor. Proposed mining activity would not directly impact any portion of the confluence AVF, as it is outside of the proposed permit area and would not be undermined or disturbed by proposed surface facilities. A small portion of the AVF has been disturbed by office facilities associated with CYCC's Mine 3 (Permit No. C-84-062). 2. The proposed mining operations would not cause material damage to the quantity or quality of surface and ground water that supply the alluvial valley floor. Given the fact [hat Foidel Creek has been converted from an intermittent to a perennial stream as a result of underground mine water and spoil aquifer discharge, and the fact that Middle Creek would be neither undermined nor diverted by the proposed operations, there is no possibility of diminution of the quantity of water supplying the alluvial valley floor. Further, the entire alluvial valley floor is flood irrigated by water diverted from the unaffected segment of Trout Creek above its confluence with Middle Creek (See TCC Life-of--Mine Application Map No. l5). The primary function of the confluence AVF is [he support of flood irsigated hayland. As previously noted, the flood irrigation water is not diverted from affected segments of either Foidel Creek or Middle Creek, but is diverted from an unaffected segment of Trout Creek. Afield inspection conducted by the Division in late August of 1986 revealed vegetation on the flood irrigated AVF to be more productive than adjacent areas upstream on Foidel Creek above the Trout Creek irrigation diversion (assumed to be sub-irrigated). The flood irrigated pasture was dominated by pasture grasses while weedy species were visually dominant on the non-irrigated reach (see vegetation data in TCC Exhibit 43). From comparison of the adjacent flood irrigated and non-flood irsigated areas, it appears that sub-irrigation has little impact on the agricultural productivity of the confluence AVF, and that flood irrigation is the critical function. Significant increases in the salinity of alluvial ground water in the confluence area would not be anticipated since the majority of the recharge to the aquifer occurs during spring and early summer when Middle Creek and Foidel Creek flows are highest and 36