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in the Tables within the Annual Hydrology Reports indicates that no samples were measured at <br /> or above the detection limit. <br /> E.) Impacts to Alluvial Valley Floors (AVFs) <br /> Two alluvial valley floor(AVF) studies were performed on Sage Creek and Grassy Creek along <br /> with their associated tributaries. The first study conducted in 1990 focused on Dry Creek, Sage <br /> Creek, and the upper portion of Grassy Creek in 1990. The second study conducted in 1992 and <br /> 1993 included lower Grassy Creek, Scotchmans Gulch,Annand Draw, and an unnamed drainage <br /> lying east of Annand Draw. As described in Tab 16, Protection of the Hydrologic Balance, of <br /> permit C-1994-082 both studies found that there is insufficient flow to support flood irrigated <br /> crops and neither drainage contains alluvial valley floors. Additional information concerning <br /> these determination as well as copies of the two studies are provided in Tab 16 and Attachment <br /> 16-3 of the mine permit. <br /> F.) Agreement of Observed Hydrologic Impacts with the "Probable Hydrologic Consequences" <br /> (PHQ Projected in the Mining Permit <br /> The Observed Hydrologic Impacts are generally in good agreement with the Probable <br /> Hydrologic Consequences projected in the mine permit. The pre-mine groundwater use was <br /> marginal for livestock and irrigation and unsuitable for domestic supply. No residential domestic <br /> supply wells are present within or downgradient of the mine area. Water quality at downgradient <br /> compliance wells SGAL-70 and YSAL3 meet all applicable water quality standards. Due to the <br /> limited potential for the mine to negatively impact the quality of bedrock groundwater <br /> compliance bedrock wells were deemed unnecessary(see Appendix 15-1 TR 39). Therefore, as <br /> predicted in the PHC no groundwater users have been impacted. <br /> Impacts to groundwater and surface water quality were addressed in the Probable Hydrologic <br /> Consequences section of the permit(Tab 17,Attachment 17-5). Projected TDS concentrations in <br /> the receiving stream alluvium were estimated from geochemical models that evaluated potential <br /> salt loads from spoil/groundwater interactions. The impact analysis projected a final TDS value <br /> of 798 mg/L at Sage Creek alluvial well YSAL3, a final TDS value of 1296 mg/L at Grassy <br /> Creek alluvial well YGAL16, and a final TDS value of 2036 mg/L at Annand Draw alluvial well <br /> SL-7 - 44 <br />