High tritium level seen at Pilgrim
PLYMOUTH — Concentrations of a radioactive isotope called tritium found in late December during groundwater monitoring at Pilgrim Nuclear Power Station were the highest detected since testing began at the plant in 2007.
Tritium — a byproduct of the nuclear fission process — was found at 69,000 picocuries per liter in a sample taken from a well adjacent to a catch basin that collects and releases waste from the reactor into Cape Cod Bay.
Pilgrim now has whale-sighting protocol
PLYMOUTH — Entergy Nuclear Operations Inc. has added provisions to its environmental monitoring to include reporting any confirmed sightings of whales in the vicinity of the Pilgrim Nuclear Power Station, according to a statement from the Nuclear Regulatory Commission.
If a whale is spotted near the plant, a security officer will contact an expert and arrange for a "priority site visit," according to the company's newly written protocol.
If possible, the expert would determine whether the whale was on the endangered or threatened species list.
If it is on either list, plant operators must report its sighting to the NRC and National Marine Fisheries Service.
The new procedure was a requirement that stemmed from an incident in January 2012 when a North Atlantic right whale known as Wart and her calf were seen in the area of Pilgrim. While it's not unusual for right whales to be present in the area in January, it was unusual for a mother-calf pair, scientists said.
They usually remain in warmer southern waters since calves have less blubber on their bodies. Water temperatures near Pilgrim were considerably colder.
Earthrise Law Center, on behalf of the Kingston-based Jones River Watershed Association, sent a letter of concern to the fisheries service and the NRC's Division of License Renewal, questioning whether the journey could affect the mother's ability to nurse or the health of the calf if it swam through the surface plume of water discharged from the plant. The letter requested reconsideration of the Pilgrim plant's operating license.
Wart and her calf eventually left the area and were seen off the coast of Provincetown at the end of January.
In April, they were back in Cape Cod Bay, both in good condition, according to a letter sent to federal nuclear regulators by a specialist from the fisheries service's Northeast office last summer.
The requirement to establish a procedure for whale sightings was made by the fisheries service.
A picocurie is one trillionth of a curie, a measure of radioactivity.
Tritium levels at the 24 groundwater wells on the plant property generally range from undetectable to about 5,000 picocuries per liter, according to Joyce McMahon, spokeswoman for Entergy Corp., which owns and manages the plant. The drinking water maximum standard is 20,000 picocuries, according to the U.S. Environmental Protection Agency.
In 2011, a well spiked to 25,000 picocuries — the highest recorded level at Pilgrim until now — and triggered a massive effort by Entergy to trace the source of the leak. It was never found.
Levels have decreased since the December spike, based on testing in early January, according to officials with the Nuclear Regulatory Commission.
On Friday, the level was 2,470 picocuries per liter, said McMahon. That amount, she said, is considered the well's "baseline level"
One Pilgrim watchdog expressed frustration over this latest development at the 42-year-old plant.
"We're very concerned about a radioactive compound that has a half life of 12 years," said Pine duBois, executive director of the Jones River Watershed Association. "It's certainly not beneficial to marine organisms, which we all like to eat."
Tritium occurs naturally in the environment in very low concentrations, according to the EPA. It is used as the triggering mechanism in thermonuclear weapons and was widely dispersed in the 1950s and '60s during the above-ground testing of nuclear weapons, according to the EPA.
It has been decreasing in the environment since then, although nuclear facilities use large quantities of it. It is also used to create luminescent signs and dials, such as in wristwatches, according to the EPA.
The EPA says on its website that exposure to tritium increases the risk of developing cancer but because tritium emits very low energy radiation and leaves the body relatively quickly, it is one of the least dangerous radionuclides.
Under its license, Entergy can periodically release tritium and other radioactive substances that have been neutralized to low levels into Cape Cod Bay under monitored conditions.
After this latest spike in tritium, plant operators stopped using a line that runs from a holding tank for the radioactive waste to a catch basin adjacent to the reactor.
Tritium concentrations fell to 20,000 on Jan. 6 and 14,300 by Jan. 9, said Neil Sheehan, spokesman for the NRC.
In an email, Sheehan said the NRC will continue to inspect and report on the company's implementation of its groundwater monitoring and "any subsurface contamination will be reviewed to ensure the public health and safety are protected."
Meanwhile one of the state's top health officials is confident the public is safe.
"The bad news is the plant's catch basin has problems, but the great news is it didn't get into the surface water or the drinking water," said Suzanne Condon, associate health commissioner and director of the Bureau of Environmental Health for the Massachusetts Department of Public Health.
"No drinking water wells are down gradient of the test well, so we're not concerned about public exposure," Condon said.
State health officials also do their own tests on samples taken at the plant, Condon said. "We haven't seen anything in the surface water."
As part of its written statement, Entergy officials stressed the downward trend. All discharges through the line believed to be defective have been suspended, and the investigation will continue, they said.
"A team has been assembled to evaluate the results of the well samples and to develop modifications consistent with our commitment to minimize the environmental impact of our operations," the statement concluded.
The Pilgrim Nuclear Power Station likely will be in the news again soon. Once federal officials analyze the plant's performance for the final quarter of last year, those officials have said they expect to downgrade the Plymouth plant — based on its number of forced shutdowns — to among the eight worst performers in the country.
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