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Statements that an independent factor "influences" a dependent variable are unfounded and should be abandoned fora phrase such as "a mathematical relationship exists between..." What weakens the argument of "influence" more is that soil depth is the only environmental factor used in the regressions. Other environmental (rainfall, average temperature, etc.) and microenvironmental factors, (soil moisture, soil Chemical parameters, etc.) which could act as underlying environmental gradients were not examined. The authors seem to assume that negative patterns in woody plant density are almost completely the result of the competitive exclusion of one or more particular herb species and do not address the potential effect of environmental influences. II. Review of Kerr Recommendations to the Reclamation Plan Pages 46 through 48 of Appendix A contain a list of ten recommendations, here numbered in the order that they appear in the memo. 1. Topsoil Depth Y.err Recommendation: The present permit commitment to salvage and replace up to 30 inches of topsoil to all reclaimed areas is unnecessary to achieve the necessary levels of revegetation success and is contrary to the mandated goals involving shrub reestablishment goals. Due to the negative influence of thick topsoils on the required reclamation goals, particularly relating to shrub densities and species diversity, a limited thickness of respread topsoil should be applied to areas where reclamation goals are important. The basis of this recommendation is the regression analysis of topsoil depth versus the (unspecified) 108 parameters. Any relationship between depth and woody Dlant density is flawed as noted above because extensive data was not collected. Furthermore, r values, and thus also r2 values, are too low on which to base any judgments. Finally, a direct relationship between soil depth and woody plant density has not been shown through direct experimentation or through the elimination of other environmental parameters that may be important. Typically; operators set up experimental plots with different soil depths to prove that less topsoil is necessary than what their permit requires. To prove that they need less topsoil than required presently by the permit, they must comply with Rule 4.06.2(4). Tne authors should have included the raw topsoil depth data in the report. At the very least, the Division would have been interested ire the average depth for each area. _S_