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Regraded Spoil Monitoring Program <br />In order to provide a feedback system to check the reliability of the overburden sampling and <br />analysis program, a regraded spoil sampling program will be initiated. The upper four feet of <br />regraded spoil will be sampled prior to topsoil replacement with a hydraulic soil sampler, a <br />bucket auger, or other suitable equipment to ensure that a suitable root growth medium was <br />provided. Two representative samples, each representing a two-foot depth increment, will be <br />collected on a 600ft x 600ft grid. The vertical sampling increments were 0.0 to 2.0 feet and 2.0 <br />to 4.0 feet. Personnel will inspect the surface spoil between grid points. If a significant change <br />in spoil characteristics is observed between grid points, additional sample sites would be <br />located. Regraded spoil will also be 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 will be closely evaluated once sufficient samples is collected to determine <br />the degree of sample variability. This sampling program will ensure 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 will be analyzed for the following parameters to determine <br />spoil suitability: PH, acid base potential, particle size (texture), saturation percent, EC, and <br />SAR. The parameter list is based upon the baseline information acquired during the pre-mine <br />overburden sampling program (Section 2.04.6). As part of the spoil monitoring program, <br />regraded spoil is analyzed for a list of parameters for suitability. One item in this list is boron. It <br />is believed that Peabody included this parameter in the test list for spoil as a precautionary item <br />since they used a dragline to move overburden at that time and they had no ability to segregate <br />the Bench 1 material and place it below the topsoil zones. A study of all the past years analyses <br />has shown that the Bench 1 material has always tested below 5 ppm, which is the normal <br />threshold limit for boron in the subsoil. Nevertheless, it will continue to be studied in the spoil <br />testing program but will not be part of the Lift B testing described in Table 2.05,4(2)(d)-1. <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 />sample grid is now oriented north-south and east-west to better reflect the current mining <br />pattern, the sample grid is 600 feet by 600 feet, and the soil samples are analyzed for boron, pH <br />(Revised Nov 2008) 2.05.4(2)(d)-8