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located within different soil series components of the same map unit, however this information is not presented in the PR-2 application. Similarly contrasting sample data are listed on the table for Map Units V WD and JBC. Based on area weighted soil type composition for Map Units JBB, V WD, and JBC, the Walsh report indicated upper lift salvage thicknesses of 18", 1", and 17" for these units, and total salvage thicknesses of 57", 14", and 48", respectively. Table 2.04.9-6 of the PR- 2 application lists salvage thicknesses of 0", 0", and 12", respectively, for these same map units. These discrepancies warrant investigation and explanation. Projected salvage thicknesses listed on Table 2.04.9-6 for each map unit should reflect consideration of area weighted soil type composition of each map unit, but there is no indication that this was the case. Please address these concerns, specify the soil series within which each sample site listed on Tables 2.04.9-6 and 2.04.9-8 was located (if known}, and provide average map unit salvage thicknesses based on consideration of area weighted soil type composition (with clarification and justification for whether the thickness represents only the upper lift, or both upper and a portion or all of the lower lift as described in the Walsh report). Any salvage depth modifications made to Table 2.04.9-6 should be incorporated on Table 2.04.9-7, and in any narrative references to topsoil replacement thickness. Both the Division and Colowyo have responsibility with respect to assuring proper topsoil salvage and replacement. Collection and presentation of sufficiently detailed premining data to characterize the soil resource and allow reasonable assessment, interpretation, and projection of salvage volumes is an important component of the process. A plan that involves planned variation in replacement thickness does not make the accuracy of soil volume projections any less important than a plan that involves uniform replacement thickness. We do not understand the claim that more detailed soil inventory information would be rendered irrelevant due to approved procedures that are currently in place. The fact that Colowyo recently was obliged to reduce replacement thickness from the originally projected 18" to 8", does raise questions regarding the adequacy of past soil inventory and/or soil salvage and replacement control measures. The plan on page R2-99 indicates minimum replacement depth of 12 inches. Average uniform replacement depth should also be specified. Narrative includes brief reference to variable topsoil replacement depth, for selected areas where plants may require a shallow or deep soil wil- be established in accordance with the post-mining land use. We encourage this concept, but a more detailed plau will need to be developed and approved before the variable depth replacement plan can be implemented. Text on page R2-99 should be amended to acknowledge that revision approval will be obtained prior to implementation of variable replacement plan.