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Regraded Spoil Monitoring Program. In order to provide a feedback system to check the <br />reliability of the overburden sampling and analysis program, a regraded spoil sampling program <br />wiN be initiated. The upper four feet of regraded spoil was sampled prior to topsoil replacement <br />with a hydraulic soil sampler, a bucket auger, or other suitable equipment to ensure that a <br />suitable root growth medium was provided. Two representative samples, each representing a <br />two-foot depth increment, were collected from a slanted grid system with 300-foot centers. <br />Although the permit required a less dense grid of 500 feet by 500 feet, WFC elected to use the <br />more closely spaced grid. The vertical sampling increments were 0.0 to 2.0 feet and 2.0 to 4.0 <br />feet. Trained personnel inspected the surface spoil between grid points. If a significant change <br />in spoil characteristics was observed between grid points, additional sample sites would be <br />located. Regraded spoil was also visually inspected for compaction, possible root growth <br />problems, and the potential for slippage at the topsoil/spoil interface. The lateral and vertical <br />sampling intensities were closely evaluated once sufficient samples were collected to determine <br />the degree of sample variability. This sampling program ensured that the top four feet of <br />regarded spoil is non-toxic and chemically/physically suitable to enhance plant growth. <br />~ ~ Originally, the regraded spoil samples were analyzed for the following parameters to determine <br />spoil suitability: PH, acid base potential, particle size (texture), saturation percent, EC, and SAR. <br />The parameter list is based upon the baseline information acquired during the premine <br />overburden sampling program (Section 2.04.6). <br />However, based on the results of the extensive overburden suitable sampling program stated <br />above, both the soil sample locations and analytical parameters changed in July of 1999. The <br />slant grid is now oriented north-south and east-west to better reflect the current mining pattern, <br />the sample grid is 600 feet by 600 feet, and the soil samples are analyzed for boron, pH and EC. <br />In the event that the sample results indicate the need, WFC will implement the Unsuitable Spoil <br />Mitigation Plan listed below. <br />Unsuitable Spoil Mitigation Plan <br />If one or more parameters fall within the unsuitable range at a given grid point, a three-part <br />mitigation plan will be implemented. <br />• (Revised s-ie-zoom 2.05.4(2)(d)- 4 <br />