Radon emission rate increases as Cotter impoundments dry

Publish Date: 6/27/2009
Guest Column
Sharyn Cunningham/CCAT Co-Chair

The U.S. Environmental Protection Agency, in conjunction with Colorado Citizens Against ToxicWaste and Rocky Mountain Clean Air Action, will hold a public meeting Tuesday. A review of radon emission regulations for uranium mill tailings impoundments will be discussed. The meeting will be from 6-9 p.m. Tuesday at Quality Inn and Suites, U.S. 50 and Dozier Avenue.

Uranium milling produces large quantities of tailings placed in impoundments. ISL uranium mines utilize evaporation ponds, as well, and are being considered for compliance under these regulations. Tailings contain large amounts of radium, and therefore, they emit large quantities of radon. Radon is a dangerous radioactive gas, and it attaches to dust particles. The National Emission Standard for Hazardous Air Pollutants (NESHAP) Subpart W is the radon emission standard for operating uranium mill tailings. Over 20 years ago, the Nuclear Regulatory Commission was recommending that the limit or standard be set at 2 picocuries per square meter per second. Instead, EPA set the limit at 20.

The Clean Air Act Amendments of 1990 required EPA to review this standard and, if appropriate, revise it within 10 years. By 2001, EPA still had not performed this non-discretionary duty. Because of concerns over air emission violations at the Cotter Uranium Mill, CCAT and RMCAA began discussions in 2006 with the EPA. Failure to reach agreement on this issue led to the filing of a lawsuit. CCAT and RMCAA requested the radon standard review from EPA, and public participation during the review through public meetings, teleconferences, and an Internet Webinar. The lawsuit is nearing final settlement. In the meantime, EPA has begun the review of the standard. The Tuesday meeting in Cañon City is the first of three meetings to be conducted to allow participation from affected communities.

Why should you care? ISL uranium mining is moving forward in Colorado. In 2007, CDPHE confirmed leakage from the Cotter Uranium Mill tailings impoundment. Radon emissions from tailings in the impoundments have been stopped by water coverage, so we are facing a no-win situation. The weight of water covering the tailings threatens the liner and will increase leakage of contamination into groundwater, while drying the impoundments and exposing tailings to the air increases the rate of radon emissions. CDPHE has directed Cotter to dry the primary and secondary impoundments.

EPA regulations require once-a-year tests for radon at uranium mill tailings impoundments, but EPA can require more frequent testing when a facility nears the radon emissions rate limit. Between 2006 and 2008, as Cotter has been drying the Primary Impoundment, tests showed a 230 percent increase in the radon emissions rate.

In 2008, Cotter’s test results were just a fraction below the NESHAPS limit. CCAT believes the current unusual circumstances warrant more frequent tests. CCAT also has requested proof that alternative measures used to control radon emissions, such as sprinkling the tailings, are supported by scientific research and evidence.

If you care about the air you breathe, or the dust blowing in our winds, participate in this hard-won opportunity for our community to have a voice in decisions that are being made in far-away places, join us in voicing our concerns and offering our personal experience and knowledge for this review.

http://www.canoncitydailyrecord.com/Opinion-story.asp?ID=11005