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Regraded Saoil Monitoring Program. In order to provide a feedback system to check the reliability of the overburden sampling and analysis program, a regraded spoil sampling program will be initiated. The upper four feet of regraded spoil was sampled prior to topsoil replacement with a hydraulic soil sampler, a bucket auger, or other suitable equipment to ensure that a suitable root growth medium was provided. Two representative samples, each representing atwo-foot depth increment, were collected from a slanted grid system with 300-foot centers. Although the permit required a less dense grid of 500 feet by 500 feet, WFC elected to use the more closely spaced grid. The vertical sampling increments were 0.0 to 2.0 feet and 2.0 to 4.0 feet. Trained personnel inspected the surface spoil between grid points. If a significant change in spoil characteristics was observed between grid points, additional sample sites would be located. Regraded spoil was also visually inspected for compaction, possible root growth problems, and the potential for slippage at the topsoil/spoil interface. The lateral and vertical sampling intensities were closely evaluated once sufficient samples were collected to determine the degree of sample variability. This sampling program ensured that the top four feet of regarded spoil is non-toxic and chemically/physically suitable to enhance plant growth. • Originally, the regraded spoil samples were analyzed for the following parameters to determine spoil suitability: PH, acid base potential, particle size (texture), saturation percent, EC, and SAR. The parameter list is based upon the baseline information acquired during the premine overburden sampling program (Section 2.04.6). However, based on the results of the extensive overburden suitable sampling program stated above, both the soil sample locations and analytical parameters changed in July of 1999. The slant grid is now oriented north-south and east-west to better reflect the current mining pattern, the sample grid is 600 feet by 600 feet, and the soil samples are analyzed for boron, pH and EC. In the event that the sample results indicate the need, WFC will implement the Unsuitable Spoil Mitigation Plan listed below. Unsuitable Spoil Mitigation Plan If one or more parameters fall within the unsuitable range at a given grid point, athree-part mitigation plan will be implemented. (Revised za nuG os> 2.05.4(2)(d)-6