2011-01-24_PERMIT FILE - M2011007 (7)

Home Browse Search

3. Site Mans See the attached oversized plats for site maps and other detail drawings. These drawings correspond to DRMS permit drawings. Not all DRMS drawings are included; only the drawing pertinent for this SWMP. • Al - Site Vicinity Map • A2 - Ownership Boundary Survey • E2 - Pre-Existing Abandoned Waste Rock Dump and Stormwater Control Elements 4. Stormwater Management Controls a. SWMP Administrator Venture Resources has selected Ryan J. McHale, PE as their SWMP Administrator. McHale is a registered CO Professional Engineer and the Company's Vice President overseeing operations. McHale can be contacted at 303-619-6323 or ventureresources a).att.net. b. Identification of Potential Pollutant Sources and Best Management Practices (BMP) Potential Pollutant Sources It should be carefully understood that this project involves cleaning up historic, abandoned mine waste rock that has been in place for well over 100 years. This project (at an offsite location already described above in Item #1) extracts nearly all of the acid-forming minerals in waste rock that are the source of acid- runoff that plague this historic mining district. By doing nothing, these piles of pre-existing waste rock will continue to leach acid and heavy metals for a very, very long time. But, by designing a carefully regulated and engineered program a solution can be achieved. Along with the environmental benefits of this cleanup, new employment opportunities and increased business within the local economy will develop. The pre-existing abandoned mine waste rock to be processed consists predominately of silica & alumino silicate minerals. The sand portion is composed of vein type material such as quartz gangue and quartz monzonite porphyries with some of the surrounding wall rock composed of metamorphic gnei.sses. The clays are formed from altered wall rock and feldspars. The acid formation occurs through a natural weathering phenomenon of the sulfide minerals, in this case pyrites, with air and rainwater. This process occurs naturally underground as a natural geologic event. The problem in this mining district is that the weathering process has been accelerated because the rock containing these minerals has been brought to the surface and deposited in concentrated piles. With increased air transfer and increased contact with rainwater, the accelerated oxidation creates an acidic ru - off more quickly that harms the environment. The potential for acid formation exist because of the weathering of sulfide minerals present, consisting primarily of iron sulfide (FeS2 or pyrite) and copper iron sulfide (CuFeS2 or chalcopyrite). These are the minerals to be removed, along with the trace associations of precious metals and heavy metals that occur. This is the material collected in the table and flotation concentrate for sale to a third party for further treatment and refining. A laboratory analysis (Synthetic Precipitation Leaching Procedure, SPLI? Method 1312) of the in-situ waste rock (solid constituents) is attached as an appendix to this SWMP application. This demonstrates the "before" state, prior to offsite processing and reclamation. • Loading and Unloading Operations: A rubber-tired loader and track excavator will be employed during daylight hours to load waste rock into dump trucks. At this location, there is the potential of stonnwater nun-off containing Page 2 of 9