“Radioactive isotopes leaking at Indian Point and four other nuclear plants across the nation could signal a new wave of environmental troubles for an industry relying on plants built as far back as the late 1950s.
“There are likely two dozen (plants), maybe more,” said David Lochbaum, a nuclear safety engineer with the Union of Concerned Scientists. “The tritium leaks that were found were by happenstance. There’s no reason to believe that that’s an unabridged listing of plants that have had or are having leaks.”
About 20 anti-nuclear groups are petitioning federal regulators to ensure that the operators of the nation’s 103 working nuclear plants accurately assess the potential for tritium and other radioactive isotope leaks and come up with strategies to prevent them.
Indian Point joined the list of leaks in August, when workers found a hairline crack at the base of a spent-fuel pool that holds 400,000 gallons of radioactive water, some of which has since migrated 300 feet to the Hudson River.
Soon after, the more dangerous isotope strontium 90 showed up in groundwater under Indian Point in concentrations three times federal drinking water limits — also apparently reaching the Hudson.
Regulators and company health physicists say there is no danger to humans because the water isn’t reaching drinking water sources, and tritium can be released into the river at permitted levels.
Entergy officials have dug 23 wells to pinpoint the extent of the leak and are looking at the 10 other plants they operate for leaks.
Since the discovery at Indian Point, two more nuclear plants were found to be leaking tritium, the most recent just last month at Palo Verde, about 35 miles outside Phoenix.
Adrian Heymer, senior director of new plant deployment for the Nuclear Energy Institute, which decides policy for the industry, said “time will tell” if tritium leaks will develop elsewhere.
“Several plants have had a problem; it’s natural to expect others. How many, I don’t know,” he said.
Ralph Andersen, the group’s chief health physicist, said he did not believe there was a common cause behind the leaks.
“I’ve heard it said that it’s a function of aging plants, but when I look at the specific plants, it’s more a function of how the plant was operated,” he said. “There isn’t as much similarity as there may seem at first blush.”
Andersen also said he was skeptical of suggestions that tritium itself was to blame by making plant components more brittle and likely to fail. He said the amounts of tritium in the plants’ water were likely too small and the exposure too limited for it to have any significant effect.
A task force of safety experts is developing steps for plant operators to check for tritium leakage and correct any problems; the recommendations will likely be acted upon at an April 13 meeting of industry executives, Andersen said.
Heymer also said that anticipated changes in design and construction — such as reformulated concrete and plastic lining in pipes — would likely prevent tritium leaks at new plants.
The Nuclear Regulatory Commission launched its own task force last month after tritium leaks showed up at three locations within six months, adding to more extensive problems that had been discovered at Braidwood in Joliet, Ill. A report is due by the end of August.
Stuart Richards, the commission’s official leading the task force, said the agency continues to believe the health impacts of tritium are minimal, although regulators and industry leaders acknowledge that public perception is a legitimate concern.
“We’re going to take a look at this issue in a broad manner and identify gaps, additional actions that perhaps we should take,” Richards said. If the agency had more extensive monitoring programs, more leaks “would likely come to light,” he said.
Richards said the task force would look at tritium in the context of whether leaks contained within the borders of a nuclear plant would factor into the relicensing issue. Indian Point’s two operating licenses are due to expire in 2013 and 2015, and opponents have been critical of what they say is a process weighted in favor of the plants’ continued operation.
Industry watchdogs want a more rigorous accounting from the operators about potential sources of tritium, a detailing of the methods used to monitor possible leaks, and assurances that radioactive material hasn’t reached surrounding property. They also want better reporting to neighbors and local officials.
Lochbaum said there also has to be clearer proof that tritium isn’t a significant health risk.
The petitioners cited a recent letter from three physicians to Gov. Rod Blagojevich of Illinois, noting a 43 percent increase in leukemia rates in the 1990s within 15 miles of the state’s largest leak — at the Braidwood location.
“The authors didn’t tie this increase to the plants, nor do we,” Lochbaum told commission officials last week. “Our concern is with the uncertainty of what’s happening where; this kind of stuff can’t be taken off the table.”
Richards said the impact of tritium exposure is minimal, as far as the commission can determine. He said exposure calculations show that a person drinking 2 liters per day of water with allowable limits of tritium would need a year to be exposed to the radiation that cosmic rays provide on one flight from Los Angeles to New York.
Regardless of how the health questions will be answered, radioactive leaks raise concerns among the public.
In much of their discussion about the potential impacts of tritium on community, the watchdogs point to what happened at Braidwood.
In Illinois, tritium has been found in groundwater at three plants: Braidwood, Byron and Dresden, home to the nation’s first privately owned nuclear-power operation. All are owned by the Exelon Corp., which also owns seven other nuclear plants in Illinois, New Jersey and Pennsylvania, including Three Mile Island.
The widest contamination is at Braidwood, where millions of gallons of tritium-tainted water started leaking in 1996 but wasn’t disclosed publicly until late last year, after low levels were found in a nearby residential well. Exelon has blamed faulty valves on a 5-mile underground pipe that carries cooling water to the Kankakee River.
As recently as Thursday, a steam leak there left 500 gallons of tritiated water pooled on the grounds.
Braidwood village resident Paul Anderson, a former Merchant Marine officer who lives with his wife in a townhouse about two miles north of the plant, said he was very concerned about the leaks and was now using bottled water for drinking and cooking.
“We never thought or suspected that these plants would have a problem,” Anderson said. “Somebody should be doing time for this; that’s the way I look at it.”
The Illinois attorney general and the Wills County state’s attorney sued last month over the undisclosed Braidwood leaks.
Craig Nesbit, a spokesman for Exelon Corp., said the company planned a cleanup.
“We’re going to scour our plants and scrub them from top to bottom, determine every piece of equipment that handles tritium, and make sure that it’s in absolutely top shape,” Nesbit said.
Closer to home, Indian Point officials note that the strontium and tritium leaks there have made company officials evaluate their other facilities. Indian Point’s parent company, Entergy, which owns 10 reactors and operates another for the state of Nebraska, has begun looking at its other locations for potential tritium leaks.
“We have a specific, comprehensive, fleetwide plan for assessing current groundwater monitoring and surveillance programs at each site,” Entergy spokesman Jim Steets said. “That grew out of what has happened at Indian Point.”
What is tritium?
Tritium is a radioactive isotope, or atomic form, of hydrogen that is produced naturally in the upper atmosphere and can be found as a gas, but most commonly occurs in water, which is formed when tritium is exposed to oxygen. It also is produced during nuclear weapons’ explosions and in reactors.
What is strontium 90?
Strontium 90 is an artificially produced radioactive isotope of strontium, a naturally occurring, soft, silvery metal that rapidly turns yellowish in air. Strontium 90 is a byproduct of nuclear fission in weapons and reactors and has been linked to bone cancer and leukemia. Strontium 90 moves easily through the environment and takes more than 29 years to lose half its radioactivity.”