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COLORADL~ DEPARTMENT OF PUBLlC HEALTH & ENVIRONMENT -Water Quality Comrol Division <br />Rationale -Page 72 Permit No. CDR-040000 <br />VI/. CHANGES AFTER PUBL/C NOTICE (cont.) <br />research, the Division found clarification in the preamble io the federal stormwater rules. As published in the <br />Federal Register (Vol. SS,No. 222) on November Ili, 1990, page 48032, third column, the preamble states: <br />"Similar to the RQ (reportable quantity] test for oil and gas operations, EPA intends to lose the <br />'contact' test solely as a permit application trigger. The determination of whether a mining <br />operation's runoff is contaminated will be made in the context of the permit issuance proceedings. " <br />The Division believes that this should be iNetpreted to mean that continued permit coverage is no longer <br />needed if it can be shown by the permittee that runoff from the mining activity site is uncontaminated <br />(including sediment). Ir will be the Division's presumption that contact does cause contamination, and the <br />permittee will have the burden of proof to show to the Division's satisfaction that runofffrom d specific Site is <br />not contaminated. Since the Division has virtually no experience in this, we have little guidance to offer <br />permittees who wish to undertake this demonstration. This may be an opportunity for the Division to work <br />with the mining industry and other stakeholders to develop strategies for this demonstration. In the interim, <br />decisions by the Division will be made on a case-by-case basis. <br />Re¢ardine an exemnHon for a¢e or size of site: The regulations state that permits are required. for active <br />inactive and mining nctivities, regardtus of their age or size. There is no fieribility for the Division to <br />exempt sites on these bases. <br />4. The termination reauirement that eouioment and "significant materials" be removed from the site and that <br />mine waste 6e removed or oermanentiv isolated. ~ ' <br />Several commentors objected to the requirement that all equipment and significant materials must be removed <br />from the site before permit coverage rnn be terminated. They suggest that old equipment and buildings ha• <br />historic value and tourism interest and should be retained for those reasons. Further, in at least one <br />Colorado county, Zoning regulations protect many of these historic structures and tailings piles. Ano[her <br />commentor asserts that overburden and rock should nor be considered "significant materials" and that it is not <br />feasible to attain compliance with this criteria in a practical manner. A few commenters objeaed.to the <br />termination requirement that all mine waste be removed or permanently isolated as being impractical, <br />infeasible or too onerous. <br />Resoonse: The regulations which require starmwater permits for imtcrive mines use very broad, language. In <br />virtually all cases where the site is still recognizable as an inactive mine or mine working, a permit may still <br />be required. In at least one case, the Division has agreed to reclassify an historic mill site as a museum when <br />an Historical Society took title to the property and undertook interpretive signage and tours. However, this is <br />not possible in the majority of casts of permittees wishing to end their permit liability. The Division does not <br />require site remediatian unless the permittee is trying to terminate permit coverage. Continued permit <br />coverage is possible with no disturbance of the historic elements. <br />i <br />Reeardine the removal of eouipment and "sirrtiftcant materials": The Division has re-evaluated the <br />terminator criteria and eliminated the requirement to remove equipmem and significant materials. The <br />deciding factor regarding whether a permit is needed is exposure of the materials in the 'contact list" <br />(overburden, raw material, intermediate products, finished products, byproducts or waste products). Once a <br />permit is deemed necessary, equipment and significant materials must be managed in such a way as to reduce <br />their potential to impact stormwater quality. Amine or mill site, where the materials on the contact list are <br />not exposed to stormwater, yet which has equipment exposed to stormwater, would not be required to obtain <br />permit coverage. The Division has revised the termination criteria to reflect this situation. i <br />Re¢ardine "overburden ": This term is not spedfically included or excluded in the definition of significant <br />material, however, 'overburden" is one of the materials in the "contact list". Tltis is the list of materials <br />rriggtr the need for a stormwater permit if comacred by runoff. The termination criteria as modified, do nor <br />include 'overburden'. The two major polltaion concerns with overburden are potential acid generating <br />material and subsequent metals loading, and sediment delivery to state waters. The criteria have been <br />