Uranium mining report warns of unique risks for VA

Uranium Mining in Virginia, the report of a two-year study by the National Research Council, a branch of the National Academy of Sciences, was released December 19, 2011.

The report, which does not address any specific locations in the state, concludes that, for Virginia, “there are steep hurdles to be surmounted before [uranium] mining and processing could be established in a way that is appropriately protective of the health and safety of workers, the public and the environment.” The report was barred by the Va. legislature from stating a recommendation on whether the state should lift the moratorium on uranium mining in Virginia.

Airborne dispersion of radioactive dust

Besides some release of radon gas (which is radioactive), airborne radioactive dust from mine operations (blasting, loading, crushing and grinding) may be spread. The report notes that surface mining is more productive of dust than underground mining, but does not quantify the radiologic air pollution risk, mentioning only that dust control measures are specified for underground mining and for crushing and grinding operations.

Chemical extraction of uranium

The report describes how the crushed and ground rock is treated in stages with various chemical solutions (depending upon the composition of the uranium-bearing ore) to leach out and separate the uranium. The process involves multiple tank baths.

Contamination of surface and ground water from stored mine tailings (waste)

Besides the usual problems of acidic mine runoff and the dissolved heavy metals it typically carries, uranium mining presents the additional problem of radioactive contamination of surface and ground water. As the report explains, the radioactive material remaining in the tailings following the uranium extraction process includes 5% to 10% of the uranium mined plus the radioactive decay products of uranium, which are thorium-230, radium-226 and radon-222. Since these components remain radioactive for many thousands of years, containment of the tailings must be essentially perpetual. (Thorium-230, for example, has a half-life of 76,000 years, meaning it takes that long for a sample of it to emit half of its radioactivity.)

The report contrasts the Virginia climate and environment with the dry, typically sparsely populated western areas where most US uranium mining is done and questions the likelihood of preventing radioactive contamination of water if uranium is mined in Virginia, stating:

“[I]n a hydrologically active environment such as Virginia, with relatively frequent tropical and convective storms producing intense rainfall, it is questionable whether currently-engineered tailings repositories could be expected to prevent erosion and surface and groundwater contamination for 1,000 years (Hebel et al., 1978). There are many reports in the literature of releases from improperly disposed tailings . . . .”

Fire, flood and seismic disruption of extraction tanks or tailings containment structures are mentioned as hazards. The report notes that Virginia’s earthquakes are located in the Central Virginia Seismic Zone, where there was a 4.5 magnitude quake in 2003. (The Coles Hill site is located in that zone.)

Public burden of preparation, regulation and perpetual management

The report identifies a number of essential preparations state and local public officials, as protectors of public safety, would have to plan and enact for any uranium mining project, including “[carrying out] a thorough site characterization, supplemented by air quality and hydrological modeling, [to estimate] any potential environmental impacts and for designing facilities to mitigate potential impacts.” The report further states, regarding disaster response planning, that “until comprehensive site-specific risk assessments are conducted, including accident and failure analyses, the shortterm risks associated with natural disasters, accidents, and spills remain poorly defined.”

Following closure and a decommissioning procedure, both the responsibility for and ownership of the site of a uranium processing operation are transferred to the public, as the report notes:

“After mining and processing has stopped and the site reclaimed, a large volume of low activity tailings usually remains. In that case, long-term stewardship may include operation and maintenance of water treatment systems or other clean-up technologies. Signage and barriers to keep people from being exposed to remaining environmental hazards may be required. Uranium processing facility tailings impoundments require management in perpetuity, with ownership of the area of the impoundment transferred to the state or federal government.“