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waters, the operator [Cotter Corporation] was encouraged to evaluate the rate of dilution that <br />could be expected by this process; <br />4. The Contaminant Transport Modeling was proposed and accepted by the <br />Division. The first modeling runs incorporated both the effects of dilution and sorption (to <br />minerals iu the stratigraphic columns); <br />5. The Division rejected the effects of sorption as being non-conservative. Modeling <br />of sorption presumes Chat contact between the contatinants is ideal, and the amount of adsorbing <br />materials through which the contaminants must travel downward were not well constrained; and <br />6. The Division noted that Cotter subsequently submitted a simple dilution model, <br />which dismissed the effects of sorption. Explanation of the model "raised questions that are the <br />subject of the remainder of this review." <br />The Division then concluded at page 4 of its Janrtary 17, 2006 review that <br />We agree that sorption should retard the movement of contaminants through this <br />stratigraphic column. The actual amount of sorption, however has not been quantified so <br />cannot be permitted in the models in an unconstrained fashion. If the ultra-conservative <br />approach of assuming zero sorption provides a simple way to reach the hoped-for <br />conservative answer, the skeptics should be satisfied. If if does not, then the Division <br />might ask for more measurement to constrain the degree of sorption within this <br />stratigraphic columm. As explained in the phone conversation [with Cotter Corporation] <br />it appears that the model does provide for sorption of multi-parameters, however the text <br />should better present input assumptions regarding the type and availability of the <br />absorbing materials. [Emphasis added.] <br />The ultra-conservative nature of Cotter's modeling effort is reinforced by the <br />acknowledgments in other agency licensing actions for activities in the same general location of <br />the mines. On or about June 15, 2007, Cotter submitted to the Division, along with its <br />additional water data related to the JD-9 Mine, a copy of the Decision Analysis issued by the <br />Colorado Department of Public Health and Environment on February 11, 2000 related to the <br />10 <br />