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Page 3 <br />Adequacy Response Letter <br />Pueblo East Pit <br />June 19, 2007 <br />10. Item III B - Included with Amendment 1 was a report prepared by Bishop-Brogden Associates, Inc. that <br />included the pump test results along with all the modeling of the aquifer in this area. Included here are copies of <br />Tables 2 and 3 from Appendix 1 of that report. However, you might want to refer to that report to see how this <br />was used in detexxnining the impact of the mining on the aquifer. The report title was "An Analysis of possible <br />Ground Water Impacts from the Pueblo East Pit." <br />11. Item III C - Youx understanding is correct and agreements have been acquired with all well owners within this <br />zone. The agreements are included in this response. Also included aze two lists. One list shows the current <br />property owner and where the registered well owner name is different the well owner's name is also shown. The <br />second list shows the wells that have been redrilled to date. <br />12. Item III D - The streambank stabilization work that will be constructed along the river bank will be done with <br />full approval by the Corps. These will be permanent and therefore they will have no impact on reclamation <br />costs. Although the unfortunate events of 2006 that resulted in a breaching of Phase 1 are of concern to Phase <br />2, in fact a repeat of that event in Phase 2 is not very likely. The Phase 1 breach was a result of the configuration <br />of the river as it flows around the large meander and the way sand bars become naturally established in meander <br />patterns. The river adjacent to Phase 2 does not exhibit those kinds of patterns due to the lack of a large <br />meander. However, the "mini-meander" nevertheless produces a very small version of the same kind of pattern <br />that developed in Phase 1. The streambank stabilization should reduce the small amount of threat to Phase 2 to <br />essentially zero because any weak zones as a result of the flow around the "mini-meander" will be strengthened. <br />13. Item V A - As explained previously, at this time there is no intention of installing the steel wall. That is simply <br />presented as an option to a slurry wall. If the cost of installing a steel wall declines below the cost of slurry wall <br />and the necessary approvals can be acquired and this can be done prior to installing a slurry wall, then a change <br />in the reclamation costs and the plan would be sought to provide for implementing this option. If you still desire <br />the wording to be revised so as to remove the steel wall option, that can be done, but it is our belief that is not <br />actually necessary given the explanations provided here. <br />14. Item V B - Regarding the issue of whether there is a deficiency in the fill requirements, as stated in the plan <br />this is not anticipated to occur. When all sources axe considered it appears at this time there will be enough. <br />Also, the way it was stated in the reclamation cost calculations was not quite clear and resulted in your thought <br />that there was a 3/4 million cubic yard deficit. What this was supposed to represent was the expected volume to <br />be available from other onsite sources such as various berms, miscellaneous waste piles, and other materials <br />including unsalable product that should become available. Most of this volume is in berms that will remain in <br />place until neaz the end of the operation. This cannot be moved into the pits for backfill until it is no longer <br />needed. Thus, there is a distinction between this fill material and fill material that will be placed as backfdl as it is <br />produced. Of course, fill that is placed as it is produced does not carry a cost, but fill that will be used for other <br />purposes until late in the operation does carry a cost for bonding purposes. That is what is expected to include <br />the 762,059 cubic yards that is included in the backfilling costs. This estimate is probably on the high side, but <br />due to some uncertainty in the volume calculations produced by the complexity of the sources, it is probably <br />better to error on the high side. <br />15. Item V C - At the end of the reclamation cost calculations an estimate is provided that was prepared in January <br />2007. The information provided there was actually extracted from the quote from Hall-Irwin. The full quote <br />document is provided in this response. It is recognized that the prices quoted are much lower than the EPA <br />