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., l-" c> en \-" the mine pits mixes with ground water derived from flows from the Fruitland Formation, the coal bearing formation at the mine, La Plata Valley alluvial ground water also substantially contributes to flows in the Sundance Pit. ,;:- Estimates of annual pit flows are presented below in acre feet. Maximum Flow ac-ft/vr Fruitland Formation Ground Water La Plata Valley Alluvial Ground Water Surface Drainage 63 35 50 Total Mine Pit Flows 148 Alluvial and Fruitland Formation ground water at the La. Plata Mine, if not intercepted by mine pit excavation, normally and naturally would reach the San Juan River, a tributary to the Colorado River. Alluvial ground water moves along the La Plata River in aSQutherly direction (FIGURE 3). The salinity range of La Plata Valley Alluvium is 764 mg/l to 2410 mg/l, with an average salinity of 1327 mg/l. Fruitland Formation ground water naturally flows through the coal in an initially southeastwardly direction, turning south and southwestwardly toward the Fruitland Formation contact with the San Juan River alluvium, west of Farmington (FIGURE 3), The natural Fruitland ground water has a salinity ranging from 798 to 4306 mg/l, and averaging 1585 mg/l. The Colorado River Basin Salinity Control Forum has provided an "Intercepted Groundwater Policy for Implementation of the Colorado River Sa~inity Standards Through the NPDES Permit 6 A.,~'" F-,