VERNON — Several times a week, a tanker truck leaves Vermont Yankee carrying 5,000 gallons of tritium-tainted groundwater.
But there may be a more convenient - and likely, more controversial - disposal option in the works: Entergy administrators and state officials have begun discussing the idea of discharging the contaminated liquid into the nearby Connecticut River.
Those discussions came to light during a June 23 meeting of the Vermont Nuclear Decommissioning Citizens Advisory Committee (VNDCAP).
Officials on both sides of the talks were quick to characterize them as preliminary, and they said further analysis of the plant's groundwater is necessary to determine whether the discharge idea is feasible.
“We're looking at it to see if, in fact, it's a viable option,” Vermont Yankee spokesman Marty Cohn said. “There's no plan for [discharges] now. There's no proposal for that. It's an option that we are exploring.”
State regulators struck a similar chord.
“We will work with Entergy on this proposal like we would any manufacturer who is proposing a discharge, ensuring that the proposal is lawful as well as protective of public health and the environment before authorizing the discharge,” said George Desch, the state Department of Environmental Conservation's deputy commissioner.
The proposal is sure to attract scrutiny beyond Desch's department. State Rep. David Deen, a Westminster Democrat known for his attention to water-quality issues statewide, is calling for a “full public review” of any Vermont Yankee discharge plan.
“Any untreated discharge is a problem, and of course in this case the possible discharge of radioactive wastewater is an added complication,” Deen said.
Unexpected amounts of groundwater have been creating complications at Vermont Yankee, which stopped power production at the end of 2014. While Entergy administrators had expected some water to seep into the lower level of the plant's turbine building after shutdown, they hadn't anticipated flows that reached thousands of gallons daily earlier this year.
The issue first was disclosed in the federal Nuclear Regulatory Commission's January inspection report. The scale of the problem became apparent the following month, when photos submitted to VTDigger.org showed that administrators had resorted to using swimming pools to store some of the so-called “intrusion water,” which is contaminated with low levels of radioactivity due to contact with the turbine building.
The swimming pools are now gone, replaced by industrial bladders and steel tanks. And Entergy has contracted with a Utah-based company, EnergySolutions, to haul away the water for out-of-state landfill disposal.
As of June 23, Vermont Yankee Government Affairs Manager Joe Lynch reported that almost 200,000 gallons of intrusion water had left the plant. “Currently, we're shipping about 20,000 gallons per week, and that is our plan going forward,” Lynch told VNDCAP members.
Plant administrators also are trying, through a “comprehensive water management plan,” to reduce the amount of groundwater entering the turbine building. They have had some success, and the current flow averages 900 gallons per day, Lynch said.
“We continue to look for ways to seal up any areas where water's coming in, and we're also utilizing a number of industry consultants who are experts in this area,” Lynch said.
He acknowledged, though, that there is no time frame for eliminating water intrusion. That means the problem represents an ongoing, additional expense for Entergy: While the company hasn't released a total figure for water management, plant administrators say each truck shipment costs about $20,000.
So Entergy is examining other ways to get rid of the liquid. Cohn said one possibility is diverting groundwater before it enters the turbine building, thereby preventing contamination and allowing for discharge via the plant's stormwater system.
So far, that hasn't panned out. “We've drilled in a number of places, and we haven't yet identified a good place for a diversion well,” Cohn said.
Another option, which surfaced during a regulatory presentation by Desch at the June 23 meeting, involves discharging contaminated water that has reached the turbine building. But there are a host of issues to work through, and the state must approve any such discharge into the river.
Cohn said the intrusion water is tested before being shipped off site. But, “if you're going to discharge into a body of water ... what other protocols do you have to put in place?” he asked. “What other tests do you need to look at?”
Desch said the answers to those questions are “a work in progress,” and the state has asked Entergy for analytical data and a water-monitoring plan.
“We have not had a chance to review the data submitted,” Desch said. “They handed me the data [June 23] at the meeting, but they have yet to submit a monitoring plan. These go hand-in-hand, so I don't want to prejudge the outcome of the evaluation.”
The Department of Environmental Conservation will focus on nonradiological contaminants, Desch said. But he also said his department will be continuing to discuss radioactive contamination issues with the state Department of Health.
Bill Irwin, the Health Department's radiological and toxicological sciences chief, said he is “concerned that the water inside the turbine building has been contaminated by intrusion through soils on site and the building walls, sumps, and other sources.”
Tritium contamination doesn't necessarily preclude discharge. The U.S. Environmental Protection Agency notes that “tritium occurs naturally in the environment in very low concentrations,” and officials say discharge discussions at Vermont Yankee will hinge on the amount of radioactive contamination present in the plant's intrusion water.
“I am aware that the water is contaminated with tritium from this intrusion, and we are verifying that the tritium is at concentrations unlikely to exceed our dose limits for radiological liquid effluents,” Irwin said.
Deen, a VNDCAP member who is chairman of the House Fish, Wildlife and Water Resources Committee and also works for the Connecticut River Watershed Council, said he hadn't known that Entergy and the state were discussing possible discharge of Vermont Yankee intrusion water.
He is inquiring about public-notice and comment periods for any permit changes that may be needed at the plant. Additionally, Deen said he wants to ensure that “the proposed changes in the permit come before the VNDCAP before [the state] approves the permit.”