2012-10-01_REVISION - M1979094HR

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G.1 Introduction Exhibit G Water Information JD -7 Mine Permit Amendment M- 1979 -094HR The JD -7 open pit mine is not expected to affect surface water systems in the project area. The JD -7 open pit mine and the underground mine are expected to have an affect on the ground water systems in the project area. A brief description of the water issues associated with the mine is included in this Exhibit G. A more complete review of the water issues associated with the mine is included in Exhibit U — EPP. G.2 Principle Aquifer The Entrada Formation is the principal aquifer in the project area. This formation will not be affected by Cotter's mining operations. Lenticular sandstones in the Brushy Basin and Salt wash members of the Morrison Formation sometimes contain isolated lense- shaped or perched water bodies. These portions of the Morrison Formations are extensively faulted which make any seepage through the pit wall highly viable. Due to the nature of the intervening layers separating the Entrada and the overlying mined formation (Morrison), no hydrologic connection has been observed. G.3 Methods of Water Handling and Treatment During the operation of the C -JD -7 open pit mine, water bars will be constructed to direct surface runoff away from areas of the pit being actively mined. Runoff from ore storage will be collected by a ditch and dike system and directed to a sump. Sumps located in the pit bottom will also collect water from the perched water bodies which may be encountered. The location of the sumps will be alternated during the project to allow extractive equipment to operate under essentially dry conditions. In terms of water treatment, the sumps will constitute the first stage in the process by settling heavier particulates. Retention time and consequently the particle deposition rate will be increased by a curtain which will impede the flow stream if required. Periodic movement of the sump will allow the removal of these settled materials, primarily soil fractions, along with the rest of the overburden. Water from the pit sumps will then be pumped through a portable 2" line to a treatment facility. Water treatment will be accomplished by a barium chloride /flocculant process, manganese dioxide filters or other suitable method for removal of Radium 226. Treatment for other constituents will be done as necessary to satisfy the discharge requirements of the existing National Pollutant Discharge Elimination System (NPDES) permit. Water will then flow to a settling pond where it will be evaporated or if necessary discharged in accordance with the conditions of the existing NPDES permit. G -1