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XVII. Operations on Alluvial Valley Floors (AVF) The Division has determined that there are three areas that deserve consideration as alluvial valley floors within the affected or adjacent area. Therefore, the following findings are in order for the areas identified as potential alluvial valley floors. The Division has identified these three potential areas based on information submitted in the original permit application. These three areas are along the Michigan River, the North Fork of Bolton Draw, and the main channel of Bolton Draw. The effects of mining on the three potential AVF"s were evaluated by the Division at the time of original permit approval. It was determined that no mining-related effects would occur on the Michigan River AVF because of the limited hydrologic relationship and distance between areas. Bolton Draw would receive drainage from the mine area, but water quality affects associated with leaching of spoils were determined to be insignificant. Additionally, no AVF areas would be physically disrupted by mining, and no change in the land use within the AVFs are proposed or anticipated. An area next to the Canadian River has been previously identified as an AVF by the Division. This area has been determined to lie outside the adjacent area for the Canadian Strip Mine and thus no written findings are required or presented in this document. Michigan River Areas of alluvium along this river have historically been flood irrigated. The river lies approximately 1.5 miles southwest of the mine, yet, no surface runoff from the permit area drains directly into the river. The Sudduth coal seam, the only water-bearing formation encountered at the mine site, dips steeply and exists at considerable depth beneath the alluvial aquifer of the Michigan River. The confining nature of the coal aquifer overburden and the low transmissivity of the coal aquifer makes the potential for adverse groundwater affects on the alluvia] valley floor of the Michigan River small if not non-existent. North Fork of Bolton Draw The North Fork of Bolton Draw is the tributary which drains the southern portion of the permit area. Although the area possesses some characteristics typical of an AVF, a close examination suggests a negative determination is appropriate. Within the permit area, two prerequisites for an AVF have been identified: a unit of alluvium and an area of subirrigation. Both areas are wider than 50 feet but only the 14.4 acre unnamed alluvial soil unit exceeds ]0 acres in areal extent. The subirrigated area comprises only 5.4 acres. In addition, this area has a perched water table, Canadian Strip Mine, C-81-026 26 July 31, 1992