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increase as a result of Yoast Mine operations. <br /> Using Seneca Property LLC's assumptions about spoil spring development at the Yoast <br /> mine, and the existing baseline water quality data for lower Grassy Creek, the Division <br /> estimated the TDS of lower Grassy Creek after establishment of Yoast spoil springs will <br /> increase by approximately five percent. Because the quantity and quality of Grassy Creek <br /> water is marginal or unsuitable for use as domestic or irrigation water, this projected <br /> increase in salinity will not affect any uses of Grassy Creek water. The only current use of <br /> Grassy Creek water (livestock watering) will not be impaired by the projected increase in <br /> salinity. <br /> Sage Creek <br /> Life-of-mine plans for the Yoast Mine anticipated coal extraction within the Sage Creek <br /> watershed during the second and third permit terms. Preliminary estimates by Seneca <br /> Property indicated that TDS concentrations in Sage Creek downstream from Yoast spoil <br /> springs could increase from 641 to 2118 mg/1. <br /> With the submittal of PR1 in 1999, Seneca Property, LLC further evaluated the probable <br /> hydrologic consequences of Yoast mining operations in the Sage Creek watershed. This <br /> evaluation occurred prior to any mine-related disturbance in that watershed. <br /> Based on Seneca Property, LLC's evaluation, the Division finds that although the company <br /> has predicted that salinity levels in Sage Creek may exceed the Division's conductivity <br /> threshold of 1.0 mmho/cm, the effects to ranching/agricultural operations along Sage <br /> Creek are deemed to be insignificant. The Division finds that the coal mining operation <br /> would not interrupt, discontinue, or preclude farming on the potential alluvial valley floors <br /> that have been identified along Sage Creek, downstream from the mining operation. The <br /> Division's findings in regard to impacts to alluvial valley floors are presented in Section B <br /> X of this document. <br /> The projected electrical conductivity values for Sage Creek were in excess of the <br /> suspected level for material damage in the original Yoast Mine application. As such, <br /> Seneca Property, LLC presented analyses of impacts of elevated conductivity levels in <br /> terms of material damage in PR1. The Division agreed with Seneca Property, LLC's <br /> analyses and found that the Yoast permit application package complied with Rule <br /> 2.07.6(2)(c) & (k), which was the subject of Stipulation No.7. The Division also found that <br /> the permit application package complied with Rule 2.06.8(4), which was the subject of <br /> Stipulation No.9. Therefore, Stipulation Numbers? and 9 were found complied with and <br /> removed prior to the submittal of the application for RN4. <br /> IV. Topsoil <br /> Baseline soils information is found in Tab 9 of the permit application package. Mine soil <br /> reconstruction is discussed in Tab 21. <br /> All available, suitable topsoil was for the most part salvaged from areas disturbed by <br /> mining and either stored in a stockpile or immediately redistributed on regraded areas. The <br /> locations of the sixteen topsoil stockpiles used during mining operations are shown on <br /> 20 <br />