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mining operations in the Sage Creek <br />watershed. <br />2. Ground Water <br />TDS concentrations in the coal aquifers <br />could increase by 70 -300 %, as a result of <br />ground water migration from saturated <br />spoils. TDS concentrations in alluvial <br />aquifers could increase by 58 -100 %. <br />However, these increases in TDS <br />concentrations for both the coal and <br />alluvial aquifers would quickly diminish <br />to about one percent within about 304.8 m <br />(1,000 ft) of the resaturated spoils. In <br />addition, none of the increases in TDS <br />concentrations would exceed livestock <br />water criteria. <br />C. Wetland values <br />No wetland values would be impacted within the <br />proposed permit area. <br />d. Floodplain /unstable geology concerns <br />No alluvial valley floors would be impacted <br />within the proposed permit area. <br />Colorado DMG has determined that mining <br />activity within the proposed permit area could <br />impact the two downstream AVFs in Sage Creek. <br />Possible impacts could include disruption of <br />farming operations on the AVFs due to <br />reductions in the quality or quantity of <br />alluvial water supplying the AVFs. <br />Colorado DMG conditioned their permit to <br />require Seneca to secure a permit revision <br />prior to conducting any mining operations <br />which might affect alluvial valley floors in <br />the Sage Creek watershed. The permit revision <br />must document 1) the characteristics of the <br />alluvial valley floors which are essential <br />hydrologic functions, 2) whether mining <br />operations will interrupt, discontinue, of <br />preclude farming operations on the alluvial <br />valley floors, 3) whether mining operations <br />will result in material damage to the quality <br />of surface water supplying the alluvial valley <br />floors, and 4) a monitoring system to verify <br />these projections. <br />10 <br />