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9. In reviewing the 2004 Annual Reclamation Report sections relevant to the issue of topsoil replacement thickness, I noticed a narrative interpretation of a remedial measure that is incorrect, and needs to be amended. In Section 8-Regraded Overburden Sampling, under Rule Requirement, there is narrative indicating that there originally was a requirement that "suspect" overburden materials were to be covered with at least five feet of acceptable material, but that subsequently this requirement "was reduced to 18 inches of topsoil cover". A Colowyo letter of January 4, 1983 and a Division letter of January 24, 1983 were referenced for the original and subsequent requirement, respectively. The minor revision sampling plan was approved by the Division as submitted in the January 4, 1983 Colowyo letter. The requirements were not modified by the Division's January 24, 1983 approval letter. Apparently, the following sentence from the Division's letter resulted in some confusion. It should be recognized that the suspect lave/s which would trigger further analysis and/or selective handling are based on the fact that 18"ofnon-saline, non-sodic topsoil will be replaced over regraded spoils. This statement merely noted that the overburden suspect levels reflected the fact that the normal reclamation practice as set forth in the approved reclamation plan would include covering graded spoils with 18 inches of good quality topsoil. It did not alter any of the remediation requirements addressed in the plan submitted by Colowyo. The referenced page from the 2004 Annual Reclamation Report should be amended as appropriate, to eliminate reference to modification of the remedial requirement to cover suspect overburden material greater than one acre in extent with at least 5 feet of suitable material. 10. Given the significant reduction proposed with respect to average soil replacement thickness, it would appear to be prudent to re-assess the current regraded overburden parameter list and suspect levels. Suspect levels for several of the parameters appear to be relatively liberal, when compared to typical suspect levels referenced in current literature and guidelines developed by various western state regulatory agencies. For example, Wyoming guidelines list pH values of 5.0 to 5.5, EC levels of 8 to 12, SAR levels of 10 to 12, and selenium levels of 0.3 to 0.8 as marginal, and boron levels in excess of 5.0 ppm as unsuitable. We would suggest that similar suspect levels would be applicable for Colowyo, unless documentation supporting alternative suspect levels is provided. Please review the current parameter list suspect levels and amend as appropriate.