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The Division's response to Cotter Corporation's Report and Previously Submitted Data: <br />On April 17, 2006 Cotter formally appealed the DMO designation to the Board. Cotter proposed an <br />extension of time to gather and submit additional ground water data to support its position that the site does not <br />constitute a DMO facility. In December of 2006, Cotter installed a lysimeter and monitoring well at the JD-8 <br />Mine. The location of the well was coordinated with DRMS staff to be adjacent to and down gradient from the <br />existing waste dump. On June 15, 2007 Cotter submitted a report to the Division indicating no water or leachate <br />had been recovered to date. <br />The Division staff reviewed the additional submitted information in conjunction with previously <br />submitted data and modeling. The review was conducted by David Bird, a DRMS Geo-Chemist: Kate Pickford, a <br />DRMS hydrology specialist, and Russ Means, the DBMS uranium permit specialist for this site. Although Cotter <br />reports that no water has yet shown up in the lysimeters, the data collection period of less than six months is <br />insufficient to argue that the lysimeters will never collect water. The Division is unable to adequately comment <br />on how the lysimeters would respond to an abnormally high snow or rain season. Although probably a razity in <br />that area, staff must nonetheless consider the implications of high precipitation events. <br />Cotter has provided insufficient data to determine the long-term effects of waste rock or ore stockpiling. <br />High precipitation events will likely result in a wetting front that moves through the stockpile and dumps, and the <br />potential for this event should be assessed through long-term sampling and monitoring. Cotter failed to submit <br />sufficient additional groundwater data as to depth and quality of underlying aquifers. The information provided <br />on June 15, 2007 does not in staff's opinion address the issue of mining impacts on groundwater aquifers <br />encountered during underground operations. Correlations between the quality of water at the monitor well and <br />underground water quality are not necessazily comparable. It is not possible with the data provided to asses the <br />impact of the intercepted aquifer from mining. The lack of such groundwater information is of primary concern <br />in the submitted hydro-geology modeling conclusions. <br />Despite these concerns, staff opinion is that contamination generated from these stockpiles will migrate, <br />albeit very slowly and only short distances from stockpiles (assuming normal precipitation) and will be naturally <br />attenuated in the soil and bedrock. The Division believes this migration amounts to a minimal threat of <br />environmental contamination; however, the operator has not adequately demonstrated through monitoring, <br />modeling, and other methods of characterization that migration of contaminates will not reach groundwater, and <br />has not, in staff opinion, supplied sufficient factual data [o overturn the DMO designation. Thus, under Rule 7.2.6 <br />(1), Cotter has not demonstrated to the Division that no toxic or acid forming materials will be disturbed in <br />quantities sufficient to adversely affect the human health, property or the environment. <br />In addition, the JD-9 Mine is unique from the other sites in that it has an active water treatment program <br />for to precipitate radium from mine dewatering. The precipitation is done through a barium chloride treatment. <br />The precipitate is collected in single lined primary and secondary settling ponds prior to discharge. Although the <br />discharge meets water standards, the treatment is for a toxic material and the precipitate is currently bonded for <br />hazazdous waste disposal. By Rule and definition the treatment of the water and its byproducts classify the JD-9 <br />Mine as a DMO in staff s opinion. <br />