Are Oak Ridge deer radioactive? What is this stuff about “internal radiological contamination” of some deer on the Oak Ridge Reservation? How bad is it?
It is well known that after WWII some radioactive materials were improperly dumped or disposed of on the property of the three atomic plants of the ORR. Those sites have been isolated and cleanup operations have been underway for a few decades and will continue for years to come.
But in some cases wildlife are exposed to the vegetation and groundwater at these sites. Certain radioactive elements, two in particular, can accumulate in the body tissues of these animals to unhealthy levels: Strontium-90 concentrating in the bones and cesium-137 concentrating in the muscle tissue. Oak Ridge National Lab radiochemists and the Tennessee Wildlife Resources Agency biologists test every deer taken for both of these radionuclides.
Since the deer hunts began in 1985 and including data from 2014, more than 12,200 deer have been harvested, and 205 animals have been retained due to internal contamination, a 1.68 percentage historically; in the last decade the rate is well below one percent [For 2016 the figure was .554 percent]. The critical threshold is 1.5 times the background radiation level. All but two of the deer retained were due to high levels of strontium-90.
While most deer retained were only slightly above the cutoff, 30 to 40 counts per two minutes, the highest reading so far was an 86-pound doe, five-and-a-half years old, taken in 1999 near the old Tower Shielding reactor site. Her bone chip measured for strontium-90 at 853 cpm.
The quota deer hunts on the ORR are some of the most popular in the state, and the deer are typical specimens of the Tennessee herd. In 2009 a pair of bucks was taken with fatally locked antlers, unusual but not unheard of in nature.