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farmlands) has reasonably strong potential for achieving success (i.e. restoring premine yield <br />capability). Considering that the B and C horizons are approved for salvage in a combined <br />(mixed) lift, and that the limited sample data available indicates the C horizon materials <br />don't appear to have reasonable potential for re- establishing the yield capability of the <br />Morgan's prime farmland, it appears there is significant risk that the reclamation plans <br />may be unsuccessful. Additionally, should the redistributed soil and substitute materials <br />be found to be unsuitable through the currently approved practice of sampling respread <br />materials instead of sampling prior to redistribution, mitigation of the resulting impacts <br />may be impractical due to the extensive mixing of A, B and C horizon and overburden <br />materials approved for use. The practice of after - the -fact sampling could lead to loss of a <br />significant portion of the prime soils (a protected natural resource), should use of the <br />substitute materials not meet suitability criteria and /or the agricultural yield standards, as <br />the respread materials may require burial, as discussed in the permit. Based on the lack of <br />a demonstration for affirming that the reclamation plan approved will reasonably conclude <br />with success, OSM's review fords that the after - the -fact soillspoil sampling practice <br />approved in the permit, is not in compliance with 2.04.9(1)(d) and 2.06.6(2)(a)(ii). <br />As mentioned in the previous two paragraphs, under the PR -6 approval the soil suitability criteria <br />established for redistributed soils is different from the suitability criteria established under the <br />2008 TR -57 revision approval. Notable among those differences is that the PR -6 criteria for the <br />Lift A no longer has an established criteria for a maximum percentage of rock fragments. In <br />addition, and the more concerning of the changes, is that the lift B subsoil (including the Bench 1 <br />overburden) now has an EC threshold requirement of 6 mmhos/cm at any one sampled location <br />or an average of 5 mmhos /cm among several sample locations. The original threshold <br />established for EC (2008 TR -57 approval) was 4 mmhos/cm for the B lift and for the Bench 1 <br />soil substitute material. The justification used for establishing an EC of 6 mmhos/cm can be <br />found on page 2.05(2)(d) -6 of the currently approved permit, which includes the following <br />statements: "The actual maximum acceptable salt level, measured by Electrical Conductivity, <br />will depend on the plant species proposed in the relegation plan and the potential for upward <br />salt movement. As pointed out in the report in Attachment 2.05.4(2) (d) -1, NRCS stated that a <br />level of 6.0 in the subsoil would not be detrimental to grasses or alfalfa. A study done by Curtis <br />Swift, PhD. of Colorado State University (Attachment 2.05.4(2) (d) -2), titled Salt Tolerance of <br />Various Temperate Zone Ornamental Plants, shows that alfalfa handles a soil conductivity of 4 -8 <br />mmho/cm. The specific species cited is Medicago Sativa which is the same as that prescribed in <br />the revegetation plan for Irrigated Cropland. Also this reference does not differentiate between <br />topsoil and subsoil. Based on this data and NRCS recommendations, the limits for Electrical <br />Conductivity are shown in Table 2.05.4(2) (d) -1A and IB for the various topsoil and subsoil <br />types. The averages will be reported for each landowner in the Soil Sampling Report." <br />The reference mentioned in the Attachment 2.05.4(2) (d) -2 and approved by DRMS for <br />establishing EC suitability does list alfalfa as being moderately tolerant to the salt content of the <br />15 <br />