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-30- calculated inflow rate per acre of mined-out workings at the Allen Mine is 0.03 9pm/acre. This value indicates a very low inflow per unit area, and represents inflows from sources other than subsided areas. Therefore, subsidence is not presently a significant source of mine inflows at the Allen Mine. Since the Maxwell and Allen Mines have similar geology and mining operations, subsidence inflows are not expected to be significant in the. Maxwell Mine. Also, mining in the immediate future will be restricted to partial extraction and development mining at the Maxwell Mine. Therefore, subsidence-related inflows will not occur at this mine. Future mining plans include the use of longwall mining and pillaring in areas to the north and south of the Picketwire Valley, and partial extraction mining under the Picketwire Valley. Subsidence-induced mine inflows, therefore, would be limited to areas outside of the Picketwire Valley. The applicant has not adequately determined the probable hydrologic consequences of the proposed underground mining operations upon springs and seeps in or adfacent to the permit area, or the consequences upon the stream/alluvial aquifer systems of Apache, Santistevan and Ciruela Canyons. This is due to a deficient inventory of ground water resources. Until the surface and ground water resources are fully inventoried and the probable hydrologic consequences of mining upon these resources is assessed, secondary and retreat mining south of the Purgatoire River and beneath the alluvium of. Santistevan Canyon cannot be approved by the Division (See Stipulation Nos. 7, 8 and 9 in Section VI, Hydrologic Balance; Ground Water of this findings document). The applicant has provided a discussion of the water quality effects of mine discharge from the Maxwell Mine upon the Purgatoire River stream-alluvial aquifer system. The water discharged from the mine is a sodium-bicarbonate type water with an average pH of 7.9, and an average total dissolved solids level of 1,112 mg/1 (see Exhibit b, Table 6 of the Maxwell permit document). Under low flow conditions, this discharge would increase the total dissolved solids level in the river by 47 mg/1; under average flow conditions the predicted increase is only 13 mg/1 (Exhibit 6, Table 8). The applicant proposes to construct a 6 acre coal refuse pile, West I refuse disposal site, at the mouth of Ciruela Canyon, Observations of the disposal site have found a spring which could come into contact with the pile resulting in a leachate that may degrade water quality. The alluvial ground water quality in Ciruela Canyon may be impacted by the proposed placement of the disposal pile. The applicant has not. provided an analysis of the impacts upon the hydrology that would occur by disposing of the refuse at this site. Also, the significance of alluvial ground water flows from Ciruela Canyon to agricultural areas in Picketwire Valley has not been defined. Therefore, an assessment cannot be made at this time about the consequences of disposing the refuse material.