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Information has not b?en provided concerning th? significance of the alluvial Vdiiey fluor t0 farming. COn;cuU2 ntiV, the DlVi;iCn dI L'St 355E""e :hat ti'e .: Creek alluvial valley floor is significant to farming and make the three required alluvial valley fluor findings. 1. The proposed mining operations would not interrupt, discontinue or preclude farming on the alluvial valley floor. The only mining activity proposed within the boundaries of the AVF is limited underground development associated with Twentymile Coal Company's Foidel Creek Mine. Impacts are not projected for reasons discussed in the Division's November, 1986, Findings of Compliance for the Foidel Creek Mine. The reclaimed slopes of CYCC's Mine No. 2 drain to Fish Creek but no mining or reclamation operations were conducted within the boundaries of the AVF and CYCC does not propose any future operations which would interrupt discontinue or preclude farming of the AVF. 2. The proposed mining operations would not cause material damage to the quantity and quality of surface and ground water that supply the alluvial valley floor. Water quality impacts to the stream/alluvial aquifer system of Fish Creek could result from a combination of effects associated with the Foidel Creek Underground 'ai~e (see the Division's November, 1986, Findings) and discharge from the spoil aquifer at Mine 2. The impact to the Fish Creek system would be most pronounced during the active mining phase of the Foidel Creek Mine, as a result of discharge of underground mine water to r'ish Creek in addition to Mine 2 spoil aquifer discharge. The combination of underground mine water discharge and spoil aquifer discharge would cause a measurable increase in salinity downstream on Fish Creek, but the increased stream salinity would not materially damage crop production when based on irrigation season average flow during low water years. As was the case on Trout Creek, the majority of the plant species identified in surveys conducted by TCC and summarized in Foidel Creek Life-of-Mine Exhibit 43 are rated moderately tolerant to salinity. Only 3.7% of the relative vegetative cover on Fish Creek was made up of moderately sensitive species. No production sampling was conducted on Fish Creek, and so a ratio of 4.5 obtained from sampled fields at the Foidel Creek/Middle Creek confluence was used to convert relative cover of 3,7% to assumed relative production of 16.6% for moderately sensitive species. As shown in Table 17, projected Fish Creek water quality for flood irrigation is approximately ,9 mmhos/cm. Projected root zone soil salinity would be less than 1.5 mmhos/cm and therefore no decrease in crop production would occur. toderately sensitive species would be expected to exhibit some decline in productivity if irrigation water conductivity were to exceed 1,0 mmhos/cm. Due to the relatively small component of moderately sensitive species, material damage would not occur unless flood irrigation water quality were to exceed 2.0 mmhos/cm (which is assumed to correspond to a root zone conductivity of 3.0 mmhos/cm). ~?