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The operator has submitted an analysis based on a mass-balance loading of TDS <br />in Fish Creek. Concentrations of TDS in mine effluent were the maximum values <br />from Spoils Spring Number 1 in the Cow Camp Creek drainage. Mean flow values <br />for June and July were used for Cow Camp Creek, Bond Creek, and an upstream <br />location on Fish Creek in the calculations. Results indicated significant <br />dilution would take place and maximum expected TDS concentrations of 607 mg/1 <br />were expected in Fish Creek below the mine. <br />The maximum TDS level projected would correspond to a conductivity of less <br />than 1 mmho/cm. A conservative estimate of the relationship between <br />irrigation water salinity and root zone soil salinity, as referenced in USDA <br />Handbook 60, is 1.5 to 1. Thus, root zone soil water applied with a specific <br />conductance of 1 mmho/cm would result from flood irrigation water applied with <br />a specific conductance of 1 mmho/cm. No decrease in production of any of the <br />species identified in data submitted by the operator would be expected unless <br />the conductivity of the irrigation water were to exceed 1 mmho/cm. <br />Significant decreases in productivity would not occur unless irrigation water <br />salinity were to exceed 1.5 mmho/cm. <br />Given the limited effect of Seneca II Mine discharge on Fish Creek surface <br />water quality, it is deduced that alluvial ground water quality should not be <br />significantly impaired. Recharge of the Fish Creek alluvium from the Cow Camp <br />and Bond Creek tributaries would be expected to be minimal compared to <br />upstream contributions. Sub-irrigation would be expected to be less affected <br />by mine discharge than irrigation using surface waters. A conservative <br />estimate of the expected effect of mining indicates that no material damage <br />would result. The Division makes the following finding with respect to the <br />Fish Creek AVF and the Seneca II Mine. The proposed surface coal mining and <br />reclamation operations will: <br />1. Not interrupt, discontinue, or preclude farming on alluvial valley floors; <br />Not cause material damage to the quality or quantity of water in surface <br />or ground water systems that supply alluvial valley floors; <br />3. Be conducted to preserve, throughout the mining and reclamation process, <br />the essential hydrologic functions of alluvial valley floors. <br />The operation is in compliance with the requirements of this section. <br />VIII. Water Rights and Replacement - Rules 2.04.7(3), 2.05.6(3)(a)(ii) <br />Information pertaining to water rights is presented in Volume III, Tab 7 of <br />the original permit application. Appendix 7-8 provides a list of specific <br />water rights held within and adjacent to the Seneca II Mine permit area. This <br />information was submitted to the State Engineer's Office during the permit <br />review process for the initial 5-year permit term. The State Engineer's <br />Office determined that there are no problems at the Seneca II Mine with <br />_17_ <br />