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State Reg. • included as Exhibits 12-4, 12-5, 12-6, 12-7 and 12-8. Ttie technique utilized was to plot the cross-sections to the bottom of the coal seam and compare pre- and postmining overburden areas. The area measured from the original land surface to the top-of-coal surface is the in-place cross-sectional area. The area measured from the reclaimed surface to the bottom-of-coal surface is the reclaimed cross-sectional area. The difference between these two areas is considered to be the amount of swell area. The amount of swell area divided by the in-place area is the swell factor. Five sections were chosen as a representative sampling of the pre- and postmine configurations. The total in-place area for the five cross-sections is 60.02 square inches. The total reclaimed area for the five cross-sections is 69.22 square inches. The amount of swell, expressed as area, is 9.20 square inches, or 15.3 percent of the in-place volume. • To determine the swell factor at the Wolf Creek area, pre- and postmine volumes were determined using a computer program called STOCK. The program was originally developed by Peabody Coal Company to determine the volume in stockpiles and adapted to determine swell factors. Volumetric measurements were made of all disturbed material within the area mined from January 1982 through August 1983. These measurements included box cut spoil, graded mining area, spoils adjacent to the pit and active pit as of September 1, 1983. Premining volumes of overburden were calculated by comparing premine contours to top of coal contours within the coal removal area, plus comparing premining contours with the graded-as-of-September 1 (1983) contour outside of the coal removal area. Postmining volumes of the replaced overburden • were measured by comparing graded-as-of-September 1 (1983) contours with top of coal contours within the mining area, plus 12-62 Revised 8/27/86