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New Horizon Mine TR-57 <br />4th Adequacy Review <br />25-Nov-2008 <br />Page 2 of 3 <br />Topsoil (Redistribution) sections of the application that were not in response to <br />Division adequacy review requests. <br />The operator did provide such response in the cover letter to the November 19, 2008 <br />submittal. The most substantive change described is that Table 2.05.4(2)(d)-1 <br />threshold suitability level for conductivity was changed from 4.0 mmhos/cm to 6.0 <br />mmhos/cm for Prime Farmland Lift B, and single lift soils. Based on further review <br />and consideration of this proposed change, we have the following concerns and <br />requests. <br />a) There are now two threshold suitability level tables proposed, with <br />differing criteria for conductivity. Table 2.04.9-2 lists a suitability <br />level of 4.0 for both "Prime Farmland Lift A" and "Prime Farmland <br />Lift B and Single Lift Soils", whereas amended Table 2.05.4(2)(d)-1 <br />lists a conductivity suitability level of 4.0 for "Prime Farmland Lift <br />A", but a suitability level of 6.0 for "Prime Farmland Lift B and Single <br />Lift Soils". There should be only one table, or if two tables, the <br />threshold suitability levels should be identical. Please amend the <br />permit sections as warranted. <br />b) NRCS had previously reviewed and indicated acceptance of the 4.0 <br />mmhos/cm criteria. Amended Table 2.05.4(2)(d)-1 lists a conductivity <br />suitability level of 4.0 for "Prime Farmland Lift A", but a conductivity <br />suitability level of 6.0 for "Prime Farmland Lift B and Single Lift <br />Soils". WFC justification for the change relates to the relative salinity <br />tolerance of forage crops grown, and the fact that since the higher <br />threshold of 6.0 would be applied to subsoil rather than topsoil, <br />seedling plants (which are more sensitive than established plants) <br />would not be affected by the relaxed criteria (since their roots would <br />not extend into the subsoil). Apparently, Dan Dearstyne of NRCS was <br />consulted and the operator indicates that Mr. Dearstyne stated that a <br />conductivity level of 6.0 in the subsoil would be acceptable for the <br />typical forage crops grown. <br />The Division is concerned with the proposed threshold level of 6.0, <br />because it would not apply solely to subsoil, but also to "single lift <br />soils" placed at the surface of non-prime farmland areas. As such, <br />seedling crops would be directly exposed to the higher conductivity <br />soils. <br />Please address these concerns by selecting one of the following <br />approaches: <br />(1) Revert to the original 4.0 mmhos/cm criteria for Lift A, Lift B, <br />and Mixed Lift topsoils.