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Section 780.18(b) Continued. Firefighting equipment will be available throughout the permit area where men and equipment are working and where combustible materials are stored. The areas will be posted with the proper warning signs for the type of material stored. Sealino of Exploration and Mine Holes There are currently no abandoned or existing underground mine openings within the proposed permit area which would require closure in conjunction with final reclamation. Kerr, in conjunction with ongoing mining operations has completed a number of exploration drillholes and water supply and monitoring wells. Generally all exploration drillholes which have not been completed for water supply or monitoring purposes have been sealed upon completion of sampling and geophysical logging. Those drillholes or wells that have been completed for water supply or monitoring purposes have been completed by placing, backfilling, and cementing casing materials in the borehole, as illustrated by Figure 20, Kerr Monitor Well Design. While detailed completion information was not recorded for each monitoring well, typical completion practices involved placement in the borehole of 3- or 4-inch slotted PVC casing fitted with a basket strainer cap. Within the designated completion intervals, the borehole annulus was backfilled with clean gravel. In the remainder of the borehole, the annulus was backfilled with drill cuttings to within approximately 4 feet of the collar and the remainder of the borehole was cemented to stabilize the casing at the surface. Well casings were cut off approximately 3 to 4 feet above the ground surface and fitted with a cap to limit access. In some cases, a steel surface casing and locking cap were cemented into the borehole. All monitoring wells except 77-14, 79-1, 79-2, 79-3, and the alluvial wells were completed in the coal seam as illustrated by well logs presented in Exhibit 11, Drillhole Logs. Well 77-14 was completed in a sandstone unit underlying the Sudduth Coal Seam, Wells 79-1, 79-2, and 79-3 were completed in the overburden immediately above the coal seam, and the alluvial wells were completed in the shallow alluvial/colluvial deposits lining several of the minor tributary drainages as shown on Map 20, Stream Channel Cross-Sections. In the Kerr North Area, slotted PVC was placed in a number of exploration boreholes to allow monitoring of ground water levels as mining operations progressed to the north. Given that these boreholes were within the area to be mined and would be mined through, they were not completed as conventional monitoring wells (i.e.: gravel pack, cement collar, etc.). MR-37 780-88 Revised -September 2002