BRATTLEBORO — Vermont Yankee administrators waited two years for the state's permission to build a new storage facility for nuclear waste at the defunct Vernon plant.
When they finally received that permit in late June, they didn't waste any time getting started.
Entergy administrators last week said the construction of a spent fuel storage facility is well under way, with a few dozen contracted workers having recently installed a massive generator that will provide emergency power to the complex.
Construction will continue into 2017. But officials say getting the generator in place was a “major milestone” as crews begin a $143 million effort to transfer all of the plant's radioactive spent fuel into sealed casks.
“The work currently is on schedule and on budget,” said Joe Lynch, Entergy Vermont Yankee's government affairs manager.
Vermont Yankee stopped power production in December 2014, and all fuel was removed from the plant's reactor the following month. But the majority of those fuel assemblies - 2,996 of the 3,880 on site - remain in a cooling pool inside the reactor building.
The other assemblies have been stashed in 13 “dry casks” on a concrete pad near the reactor. The state Public Service Board approved construction of that storage area in 2006.
A second storage pad
Entergy administrators say they will need a total of 58 casks to hold all of the plant's spent fuel. So they applied in June 2014 for a state certificate of public good to build a second storage pad adjacent to the existing pad.
A lengthy and sometimes contentious permitting process followed. Part of the delay was at Entergy's request, as the company needed more time for engineering work.
But there also were numerous objections to Entergy's plans. Some wondered whether the fuel pad's location could negatively impact the cost and schedule for Vermont Yankee decommissioning, while others questioned the safety and visibility of the proposed storage facility.
Entergy vigorously defended its proposal, saying any attempt to relocate or redesign the spent fuel pad would take years and cost hundreds of millions of dollars.
On June 17 - nearly two years after Entergy filed its petition - the state Public Service Board approved Entergy's plans.
Work on the fuel storage project began the following month. While Entergy is supervising, Florida-based Holtec International has been contracted to handle all aspects of the job including construction of the pad, fabrication of storage casks and loading those casks on site.
This month, crews installed a 200 kilowatt diesel generator that will supply backup power to the fuel-storage facility and other Vermont Yankee facilities. The generator - which sports a 1,200-gallon fuel tank, according to state documents - is expected to be operational in October.
In a presentation to the Vermont Nuclear Decommissioning Citizens Advisory Panel Sept. 22 in Brattleboro, Lynch said Holtec also has begun fabricating fuel storage casks for Vermont Yankee.
“Twelve of them have been completed out of the 45 additional casks that we need,” Lynch said. “Those cask systems will be delivered in the fourth quarter of this year.”
Preparing the site
The concrete fuel pad - which will be 3 feet thick and will measure 93 feet by 76 feet - can't be poured until crews remove an old storage building called the North Warehouse. Given the potential for asbestos and other nonradiological waste, the warehouse work will be overseen by the state Department of Health and the state Agency of Natural Resources.
Also, state Nuclear Engineer Tony Leshinskie said he is frequently on site.
The fuel pad work will continue into 2017, when Entergy expects to begin moving spent fuel from the cooling pool to dry casks. Lynch reiterated at the Sept. 22 meeting that all fuel will be in dry cask storage by the end of 2020.
All told, the project is expected to cost $143 million. Entergy has taken out lines of credit to cover that project, and the company expects to take legal action against the federal government to try and recoup that cost.
That's because federal officials haven't met their legal obligation to create a central repository for the nation's nuclear waste. While the U.S. Department of Energy has begun planning for the eventual removal of Vermont Yankee's spent fuel, there isn't yet any a place to take it.
The fuel pad project is the biggest thing happening at Vermont Yankee at the moment. By the end of June, Entergy had finished draining and “laying up” plant systems that are no longer needed, Lynch told the advisory panel.
Administrators are still shutting down buildings at the plant site. “We've been consolidating our staffing and use of those buildings so that we can remove services and power,” Lynch said. “The obvious reason is to minimize the cost impacts on the [plant] as we head into the next winter season.”
Water intrusion continues
Entergy also is still wrangling with a water-intrusion issue, as groundwater continues to leach into the plant's turbine building. That water must be trucked off site for out-of-state disposal because it is contaminated with low levels of tritium.
Last month, a plant spokesman said the problem had been curtailed enough that administrators no longer were pursuing a proposal to discharge tainted water into the Connecticut River.
Mike McKenney, who serves as technical coordinator for Vermont Yankee decommissioning, said the company is working to restore an underground barrier between the turbine and reactor buildings.
Administrators expect to see “a significant reduction” in water leakage due to that effort, McKenney said. “Based on the results of that, we'll determine what our next steps are and what our options are,” he said.
Leshinskie, the state nuclear engineer, said he recently participated in a federal Nuclear Regulatory Commission meeting regarding lessons learned from the Japan's Fukushima nuclear plant, which was disabled in 2011 by a powerful earthquake and tsunami.
Leshinskie said he was struck by the similarity between the water-control measures that have been implemented at Vermont Yankee and at Fukushima since the disaster. The key difference, he said, is that Entergy has been able to reduce the water-incursion rate at Yankee, while Fukushima is still dealing with the incursion of 5,000 to 10,000 gallons of water daily.
“In a few more months, we'll know whether the current efforts [at Vermont Yankee] have been successful,” Leshinskie said.