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The applicant has indicated that the agricultural practices along the two valleys are predominantly native pasture and hay for stock. There are also some apple orchards in the area, and some fields in small grains (e.g. wheat, oats, and barley). The applicant has provided no specific information concerning the agricultural significance of the alluvial valley floor to farming. Therefore, the areas designated as alluvial valley floor are assumed to be agriculturally significant, and the Division will make all three alluvial valley floor findings for the Ward Creek - Williams Creek alluvial valley floor. Based on the information provided by the applicant, the areas designated as Qaf, Qtl, Qt2 and Qt3 along the Ward Creek and Williams Creek Valleys are designated as alluvial valley floors because of flood irrigation capability. Alluvial Vallev Floor Findings Pursuant to Rule 2.06.8, the Division is required to make specific written findings on the effect of mining on all AVF's within the permit and adjacent area. The required findings are presented below. The mining operations did not interrupt, discontinue, or preclude farming on the alluvial valley floor. The surface facilities associated with the mine are located outside of the area designated as alluvial valley floor. The operation did undermine portions of the area designated as alluvial valley floor but it did not affect farming activities. The applicant performed limited mining (the extraction ratio will be between 50 and 55 percent), and, therefore, no significant surface effects from subsidence were expected. In addition, the applicant has a subsidence monitoring plan (Section 2.05.6(6)(f)(ii)(c) of the permit application). The mining operations would not materially damage the quantity or quality of surface and ground water which supply the alluvial valley floor. During mining operations, the underground mine slightly deplete flows in the stream/alluvial aquifer system, and the discharge of water from the underground workings affected water quality in the Carbon Ditch and in Ward Creek. After mining operations, when the natural ground water flow pattern is restored, water passing through the underground workings would affect water quality in the Williams Creek and Ward Creek stream/alluvial aquifer system. A quantitative assessment of these effects is provided in the discussion of probable hydrologic consequences contained in this findings document. That assessment predicts the stream flow depletion to be less than 2 percent of the average stream flow in Ward Creek, and less than 7 percent of the lowest stream flow observed in Ward Creek. The predicted water quality resulting from the mining activities would not prevent the use of surface water for flood irrigation. -22-