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~~ <br />discharge, at some point, to groundwater, a groundwater compliance point will ultimately be <br />established. It was recommended that until a parameter list is established for groundwater, <br />CC&V should measure atl analytes that may be regulated under groundwater requirements. <br />3. It was noted that some of the analyzes were not measured to levels low enough to detect <br />regulatable quantities of the parameter of concern. It was recommended that these parameters <br />be remeasured, or that future modeling results demonstrate compliance at surface water and <br />groundwater compliance points using realistic methods. <br />4. With regard to the Ironclad tailings tests and modeling results, it was noted that CC&V's <br />modeling results were extremely conservative. In some cases, the modeling results failed to <br />demonstrate that waters leaving the controlled area would be m compliance with water quality <br />standards, and it was noted that these particular failures may have been due to the overly- <br />conservative assumptions. It was recommended that the model be re-run, that more realistic <br />assumptions be employed, and that the model consider the full list of gecehemical components <br />that might regulated by both surface water and groundwater. <br />5. It was agreed, as a working thought, that CC&V would construct a test cell into which compacted <br />tails from the Ironclad would be surface flooded with water and the leachates would be tested <br />following a fixed period of flooding. The purpose of that test was to provide a more realistic <br />synopsis of the actual field conditions that might be anticipated. The test was to simulate subfloor <br />flooding of that portion of the soil liner that will not be lined with a geomembrane. <br />Contrary to the the fast paragraph of CC&V's July 7 memo, the Division did not provide approval <br />to utilize the liner materials. To date, the Division has not received adequate information to make <br />such an approval. <br />Contrary to the memo, the Division did not agree to the assumption that " 25 percent" of the <br />concentrations measured for the MV/MP test actually would be found in the seepage. The Division <br />did agree that the modeling assumptions were conservative, but CC&V have not presented an <br />alternative model with appropriate justifying assumptions. <br />Although CC&V have re-run the fate and transport model for the Ironclad liner materials, the <br />assumptions presented in the July 7 memo are not supported or justified. <br />1. Assumption 1 is that ten percent of the geomembrarre is ineffective and therefore Ironclad <br />material may be contacted by underpad flows through that 10 percent of area. This appears to <br />be conservative for the geomembrane-lined ama, but it does not consider the area that is not lined <br />with geomembrane. <br />2. Assumption 2 is that measured metal concentrations will represent 25 percent of actual under field <br />conditions. This assumption, though intuitively reasonable and conservative to me, nonetheless <br />is arbitrary. It needs to be supported. <br />3. Assumption 3 is that Arequa Gulch flow is 7343 gpm. That figure does not sound arbitrary, but <br />where did it come from? <br />