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3. Narrative on permit pages 2.05.4(2)(d)-11 through the first half of page <br />2.05.4(2)(d)-13, regarding topsoil salvage procedures, appears to correspond to <br />the Findings Document. However, narrative on page 2.05.4(2)(d)-13 under <br />Topsoil Salvage Techniques-Year 2001 and Onward, diverges from the <br />procedures described in the Findings Document in many respects. This section <br />describes salvage of Lift "A" only, with this soil material to be spread on final <br />graded spoils, with a minimum goal of approximately one foot of laydown <br />thickness. Narrative later in this section states that topsoil redistribution will no <br />longer consist ofphased campaigns as in the past, but will be an integral, <br />ongoing portion of the mining operation. The Lift B material will consist of <br />suitable material selected from the upper bench and is essentially the same as the <br />uppermost four foot of regraded spoil as described in an earlier section. <br />Also, the version of Map 2.05.4-4 in the current permit document does not <br />indicate separate replacement thicknesses for the individual replacement blocks, <br />as described in the Findings Document. Rather, each of the blocks (A through D) <br />is designated to receive a 10 inch top lift and a 12 inch lower lift, for an average <br />soil replacement thickness of 22 inches for each block, regardless of the original <br />soil resource present in the block or the associated land management category. <br />For Block A, the proposed average replacement thickness would equate to <br />approximately %Z of the replacement thickness originally approved. The dominant <br />soil unit in this block is the 98E (Darvey-Bari complex), deep eolian/alluvial soils <br />that supported irrigated hayland prior to mining. Based on tables included on the <br />Soil Baseline Map (Map 2.04.9-1) as well as Table 2.05.4(2)(d)-3, on page <br />2.05.4(2)(d)-3 of the application, a total average salvage thickness of 4.4 feet was <br />projected for the 98E map unit (1.4 foot top lift and 3.0 foot lower lift). <br />Replacement of a minimum I foot thickness of topsoil over blasted overburden <br />would almost certainly not be sufficient to restore premining agricultural <br />productivity levels within the irrigated hayland and irrigated pasture blocks where <br />deep soils predominated prior to mining (Blocks "A" and "B"). In the RN-4 <br />Findings Document, the Division did determine that salvage of lower portions of <br />the "B" and "C" horizons, separate from the upper soil horizons, was necessary to <br />be replaced as subsoil in order to ensure soil productivity consistent with the <br />approved postmining land use, for those units occurring on irrigated hayland and <br />irrigated pastureland, pursuant to Rule 4.06.2(3). Current permit application <br />narrative on page 2.05.4(2)(d)-13, under Topsoil Salvage Techniques, indicates <br />that only upper lift soil would be salvaged, and replaced directly on regraded <br />spoils. This conflicts with the determination made by the Division in the RN4 <br />Findings, that two lift salvage and replacement was necessary. <br />Two lift salvage and replacement is warranted for these thick agricultural soils, to <br />avoid dilution of the chemical, physical, and biological characteristics of the <br />upper sub-horizons, which contribute to the productivity of the native soils. The <br />two lift, 22 inch average replacement thickness for Blocks "A" and "B", presented <br />on the current version of Map 2.05.44, would be an improvement over a single <br />6