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STATE OF COLORADO DIVISION OF RECLAMATION, MINING AND SAFETY Department of Natural Resources 1313 Sherman St., Room 215 Denver, Colorado 80203 Phone: (303) 8663567 FAX: (303) 832-8106 March 3, 2007 To: Deb Gonima C~ b `.~°zfvFiwl a~w~e~ " ~ Y"I~ ~1~ry/~ f1~!'U7 G ~"°"~ COLORADO DIVISION OF RECLAMATION MINING SAFETY Bill Ritter, Jr. Governor Hanis D. Sherman Executive Director From: Berhan Keffelew~ Ronald w. cottony Division DlreCtor Re: Review of Aci Base Accounting reaulta from Permi # M-2006-03 Natural Resource Trustee Ae you requested I have reviewed the supplemental materials submitted by the operator to justify why, the material proposed to be extracted (ore and over burden} when exposed to the elements, would not be an acid generator. The Division had requested the operator to provide a simple acid/ base accounting results of the ore and overburden that will be mined under the proposed 110(2) permit. If a simple acid / base accounting would not be available, to provide the results of the assay of the ore and overburden, so the Division can calculate the total sulfur content of each. Based on the results, the Division was to determine if the operation would meet the requirements of CRS 34- 32-112.5. No toxic chemicals are being proposed to process the ore under the proposed permit. operator provided paste PH and acid base accounting results, 3 from the ore, 2 from the overburden and a sample of pyrite ore. The operator included in its submittal, a report from the Colorado School of mines on "Acid Producing Potential of Mine overburden'•. The article explains the testing procedures for paste PH in determining the acid producing potential of the mine overburden. The last two pages of the report listed the actual test results from the ore and overburden, in mole H+/100 Kg for neutralization Potential and CaC03/1000tons, for Acid Producing Potential. According to the reaulta submitted, no acid producing materials were detected on the samples tested, As a foot note the operator also stated that to date, "NO Acid producing materials (i.e. sulfides) have been found at The Steel Rose Mine". Since the testing and results were not conducted in an independent lab, the Division contacted Mr. John O'Neill, who stated that he ie a professional Chemist and that he supervised the testing procedure. The Division requested a written statement saying, Mr. O'Neil as a professional Chemist supervised the testing procedure and it was as described in the supplemental material provided with the teat results. Mr. O'Neil agreed to provide the letter as soon as possible, so it will be part of the record. The operator has agreed to conduct paste PH teats on all ore and overburden exposed to the air, and if the PH of the paste teat is less than 7, operator has also agreed to further investigate using acid base accounting (ABA), and provide the Division with the reaulta. For now, the submitted reaulta for the ore and overburden will be accepted given the size of the ore and overburden that is expected to be exposed at any given time to the elements during the life of the operation as submitted. In the future, however, since Past PH analysis provides no indication of long-term/neutralizing potential of soils/rocks, the Division will require the operator to describe in detail the methods of the test i.e. the size of the air dried material TESTED in grams, the quantity of DI water used to get the 1:1 ratio and the elapsed time before the PH was measured. The same detail information will be needed for the Acid/Ease Static testing method. All future teat results have to also be signed, verifying the results by the professional Chemist who supervised or conducted the tests. if future test results show the potential of the ore or the overburden to generate Acid, the Division will implement CRS 34-32-122.5, and notify the operator of any changes to the mine Office of Office of Mined Land Reclamation Denver Grand junction Durango Active and Inactive Mines