CARSON CITY, Nev.–State regulations, enacted in 2006 that require mercury emissions controls to reduce the amount of mercury emitted into the air from precious metal mines, are producing some early positive results, according to the Nevada Division of Environmental Protection (NDEP).
In an update on recent activities, NDEP Administrator Leo Drozdoff today announced that the Mercury Air Emissions Control Program has resulted in recent proactive actions by two mining companies to reduce mercury emissions, as well as an enforcement action against one company.
He applauded two companies for their early installation of new and improved mercury emissions control equipment in accordance with the incentive portion of the regulations.
Goldcorp and Round Mountain Gold Corp. have installed deep-bed sulfur-impregnated carbon filters on mercury emitting units at their Marigold and Smokey Valley mines respectively.
Preliminary test results reported by Goldcorp show a dramatic reduction in annual mercury air emissions from those units at its Marigold Mine, from 893 pounds in 2006 to less than one pound in 2007. Round Mountain will report its results soon. By taking the risk of installing new technology before their Nevada Maximum Achievable Control Technology (NvMACT) requirements have been determined, the companies will each earn an Early Reduction Credit (ERC). An ERC gives a company two extra years to modify or replace its mercury emissions control equipment, should NDEP determine that the technology they’ve installed does not meet the yet-to-be-established NvMACT requirements.
Drozdoff also reported that an aggressive enforcement action was taken earlier this week against one company. In what Drozdoff called “the culmination of a year-long investigation,” NDEP has ordered the shutdown of the ore roasters at Queenstake Resources’ Jerritt Canyon Mine north of Elko. The shutdown is due to the company’s failure to fully comply with two previous orders.
As a result, the company now must install and operate new, more effective mercury emissions control equipment on the ore roasters, as specified by NDEP, by Dec. 31, 2008. If the company wants to restart the roasters prior to the end of the year using its existing pollution control equipment, it must install, calibrate and maintain new instrumentation necessary to properly operate the equipment. NDEP must approve the new measures before the start-up could occur.
“These events demonstrate not only that the incentives we’ve built into the program are producing early emissions reductions, but also that the regulations contain strong enforcement provisions,” said Drozdoff. “This is exactly how the program was intended to work.”
Michael Elges, chief of the Bureau of Air Quality Planning, explained that the phased implementation of the program is progressing well, although the workload is heavy. During Phase I, each mercury-emitting unit is required to be tested at the stack, and once a year thereafter.
The 2007 testing has been completed, and the last of the test results are expected to be submitted to NDEP by the end of March. He said the test results will provide the most detailed data collected so far, with which to determine annual mercury emissions from precious metal mines in Nevada. In addition, all the regulated companies have submitted their NvMACT applications to NDEP for determination of the type of equipment they will be required to install on each unit. Once their NvMACT is determined, the companies will, for the first time, have mercury emissions limits set forth in permits.
In addition, the permits will establish the specific procedures for the NvMACT controls the companies must follow for emissions reporting, monitoring, work practices, testing and recordkeeping. If the companies fail to comply with any of the permit requirements, they could face stiff monetary penalties and other enforcement actions, up to and including stopping operation of the violating unit.
Elges noted that NDEP field staff has been conducting, and will continue to conduct, regular unannounced inspections of the facilities to ensure compliance.
“In general, the industry has been very responsive to the program’s regulatory mandates,” said Colleen Cripps, Ph.D. and deputy administrator for NDEP in charge of air programs. “It appears that the industry is committed to reducing its mercury emissions as much as possible and a soon as possible.”
She noted that the NvMACT requirement will bring about continuous improvements in mercury emissions control across the state, because as new and better technology emerges, the mining industry will be required to continually upgrade the control equipment on its new or modified mercury emitting units.