Laserfiche WebLink
<br />^ BMR geologists familiar with the project have identified four <br /> separate and distinct rock types present on site. We have <br /> included a geologic cross section which we request that the <br /> Division hold confidential in accordance with C.R.S. 32-34- <br /> 112(9). This cross section shows the approximate extent of each <br /> rock type. <br /> <br /> BMR geologists selected several care holes representative of the <br /> project geology for use in the testing program. The core was <br /> selected as described in the response to Comment 7. The core was <br /> sent to SRK and SRK laboratory personnel in consultation with <br /> SRK's geochemical expert selected two distinctively different <br /> samples for each of the four rock types. The two different <br />1 samples were selected in an attempt to model both expected <br /> overall conditions and expected worst case conditions. In the <br /> Santa Fe Conglomerate, the pink gneiss and the mudst.one rock <br /> types, the different samples were selected based on color <br />' differences, indicating either a composition change or oxidation. <br /> In the case of the biotite/ biotite amphibole gneiss rock type, <br /> the different samples were selected based on a change in grain <br />size which indicated possible reworkin <br />of the material <br /> g <br />. <br />Exhibit D, Section D.3.3.2 revised to include this information 4/20/89. <br />' 9. The results from the humidity-cell test of the interburden indicate <br />sulfate concentrations to vary significantly from week to week. Please <br />t discuss why this occurs. Please describe why the cumulative sulfate <br />data reported does not appear to 6e additive throughout 'he test <br />period? <br />' Response: The humidity cell tests are designed in an attempt to model <br />actual field conditions. As shown, the sulfate data as well as <br />the other measured constituents (pH and conductivity) experience <br />' variation frcm week to week. Any water quality measurements taken <br />over 2 months time will vary from week to week as a result of <br />different levels of oxidation within the sample and the <br />' geochemical reactions that occur over time. The most important <br />information to note in the interburden humidity cell test is that <br />the sulfate is not continuously increasing, nor is the pH <br />decreasing, trends which together would be indicative of acid <br />' generation. Given the lack of these trends in the humidity cell <br />data, there is no potential for acid generation from the <br />interburden waste rock. <br />The cumulative sulfate data is additive throughout the test <br />period. The addition is not a matter of simply adding the sulfate <br />values to get cumulative sulfate since the sulfate values are <br />expressed in mg/1 and the cumulative sulfate values are expressed <br />in total mg. <br />' No application change necessary. <br />10. The individual tests performed on the interburden, overburden, and <br />' waste rock along the fault zone indicate that the interburden has a <br /> <br />