NRC: Tritium response is to emotion, not risk

LISLE – The tritium issue that first saw light at Braidwood Generating Station five years ago is fueling headlines today at Yankee Nuclear Power Station in Vermont.

"The focus of tritium leaks in the nuclear power industry started at Braidwood," noted Viktoria Mitlyng, spokesman for Nuclear Regulatory Commission Region 3 at Lisle.

"The attention right now is on the East Coast, where there are dozens and dozens of articles written on it, all negative, and thousands of entries on the Internet."

In early January, Vermont Yankee reported to the Vermont Department of Health tritiated water samples taken from some of its piping. This prompted NRC Chairman Gregory Jaczko to note, on Feb. 17, that leaking pipes and tritium is an issue "that has drawn a good bit of attention lately."

Tritium is a naturally occurring isotope of hydrogen that emits a very low level of radiation. It is found in more-concentrated levels in water used in nuclear generating stations.

The NRC went on record in the Braidwood incident to say public health and safety were not jeopardized by the releases.

Vermont Yankee officials verified a leak Saturday in an underground pipe, which likely contaminated the soil nearby with radioactive solids and with tritium east to the Connecticut River.

The officials noted Sunday the only radioactive contaminant detected in any monitoring wells is tritium.

Braidwood Station make public in late 2005 a series of tritiated water leaks that began in 1996, and released six million gallons of tritiated water into the ground at and near the utility.

The underground tritiated water plume spread 400 feet off-site into a drainage ditch. Braidwood Station has since put a plan in place to draw the plume back within the plant's boundaries.

Jaczko said he asked the NRC staff last fall to begin checking the agency's general approach for inspecting and dealing with aging pipes.

He noted a similar episode last year in New Jersey told scientists a great deal "about how buried pipe behaves over the years, and the importance of ensuring the right piping is installed in the first place."

As a scientist, Jaczko said he knows the relative risk of exposure to tritium.

"In the grand scheme of radiation, it is well down the scale, but in the area of public perception, it takes on greater significance," he said.

Mitlyng noted Jaczko is saying tritium is not a public health concern.

"But in the eye of the public, it's a large issue," she said.

"They want to know what's being done. The public's response is, 'Your federal agencies say there's no health concern. But, we don't want to see these leaks.'"

Public outrage about Braidwood developed because tritiated water moved off-site – the only instance nationwide where it was found beyond a generating station, Mitlyng said.

"When they say tritium won't harm anyone because the concentrations are so low, people have difficulty believing a small amount won't hurt them," she said. "They say, 'We don't know what amounts of radiation do to human health, so we assume any amount will be harmful.'"

However, no scientific or medical evidence shows any kind of response by human organisms to low levels of radiation, Mitlyng added.

"We can only regulate to existing scientific knowledge – internationally accepted radiation standards," she said.

Prior to Braidwood, if a tritiated water leak occurred on a generating station's property, it wasn't a safety concern.

"When Braidwood happened, we took the first step to say it's not the NRC's concern, but a public concern, and we have to respond," Mitlyng said.

"People really didn't understand there wasn't a problem. Our concern is to protect the health and safety of the public, not the emotions."