BRATTLEBORO — State regulators and anti-nuclear activists are taking a stand against a proposal to reuse large amounts of Vermont Yankee's concrete as fill when the plant is decommissioned.
The latest objections to the so-called “rubblization” plan come from the Vermont Agency of Natural Resources and the state Public Service Department. Officials wonder whether the former nuclear plant's concrete is safe and suitable for burial at the Vernon property.
“We want to feel comfortable ... that the material is truly clean,” said Chuck Schwer, director of the agency's Waste Management and Prevention Division.
But the plant's proposed buyer, NorthStar Group Services, says rubblization is common and offers environmental and safety benefits. At a Sept. 28 meeting in Brattleboro, NorthStar CEO Scott State promoted and defended his Vermont Yankee cleanup plans.
“Our objective here is pretty simple,” State said. “We expect to clean the site up. We expect to do it in a safe and compliant manner and deliver a site that's not impaired, that's not a brownfield site. It's a site that can be redeveloped and used for other purposes.”
Entergy stopped power production at Vermont Yankee at the end of 2014 and wants to sell the plant to New York-based NorthStar by the end of next year. NorthStar says it can restore most of the site as early as 2026, decades faster than Entergy had proposed.
The change of ownership is under review by the federal Nuclear Regulatory Commission and the Vermont Public Utility Commission.
Point of contention
In the state's review, Vermont Yankee's site restoration standards may be the biggest point of contention. At issue is how much NorthStar, after satisfying the NRC's radiological cleanup requirements, will restore the site for future reuse.
At the Sept. 28 meeting of the Vermont Nuclear Decommissioning Citizens Advisory Panel, State addressed both radiological and nonradiological issues.
First, he reiterated the company's pledge to pursue a residual radioactivity exposure level of 15 millirem per year at the decommissioned Yankee site. That is below the NRC's 25 millirem requirement for what the federal agency calls “unrestricted” release of a nuclear plant site.
Also, State outlined NorthStar's plan to remove underground structures such as foundations and piping down to a depth of 4 feet. The proposal also allows for “removal of structures below that level if those structures are contaminated,” State said.
That standard is up for debate. Schwer, in testimony filed with the Public Utility Commission, said he is concerned about how those structures that will be left in place will be sampled for contamination.
Furthermore, Schwer wrote that “allowing underground structures to remain in place may limit future uses of the site.”
Future use was a topic at the Brattleboro meeting, with State saying NorthStar is tailoring its remediation work for industrial redevelopment. When pressed, State said it is possible the property could be available for residential use, but he isn't sure it would be a marketable spot for homes.
That is in part because, even after decommissioning, Vermont Yankee's spent fuel will remain on site under 24-hour guard until the federal government develops a central repository for such material.
“I wouldn't say you wouldn't be able to live there. I'm just not sure people would want to,” State said.
Intense scrutiny
Whatever the property's future, NorthStar's plan to bury rubble there is coming under intense scrutiny.
Testimony from NorthStar and Entergy has shown that as much as 1.1 million cubic feet of crushed concrete could be reused as fill at Vermont Yankee. State sought to reassure officials that only “clean aggregate” will be used.
State said he has heard concerns that NorthStar would mix clean rubble with contaminated rubble. “That's not our intention,” he said. “That's never been our proposal.”
He also said the rubblization plan isn't a guaranteed money-saver.
Entergy testimony has indicated that NorthStar “could save millions of dollars” by reusing concrete at Vermont Yankee. But State said the work involved in testing, decontaminating, and crushing concrete could cancel out savings associated with transportation and landfill disposal.
“On any given project, you can't really figure out what [the potential cost benefit] is until you get into it,” State said.
There are other advantages, though. Doug Larson of Geosyntec Consultants, a firm not connected to the Vermont Yankee project, told the nuclear advisory panel that rubblization is “pretty widely used” in construction and is accepted by the NRC in nuclear decommissioning projects.
Clean concrete “can be used as an environmentally safe fill” without long-term concerns about water contamination, Larson said.
He also noted potential environmental benefits such as decreased landfill use and decreased use of disposal trucks, which can reduce a project's carbon footprint.
More trucks also would mean more heavy traffic on local roads, and that could be a safety concern. If NorthStar can't reuse concrete, it will have to bring in large amounts of fill from other places, State said.
Due to the railroad infrastructure at Vermont Yankee, “we can move [concrete] material off by rail, but we have to move material back in with trucks,” State said. “We're looking at some 3,000-5,000 loads of material that would have to come to the site.”
Persistent concerns
The purported advantages of rubblization aren't sufficient to override some observers' concerns.
Schwer told the advisory panel that, contrary to Entergy's claims, the true extent of contamination at Vermont Yankee remains a mystery. And officials say it isn't yet clear how NorthStar will address such contamination before crushing and burying concrete.
If tainted concrete is buried, Schwer wrote in testimony filed with the utility commission, “there is the potential that residual contamination could remain undetected below the surface, spread over time, and pose a risk to public health and the environment.”
Another problem is that Entergy, in previous dealings with Vermont officials, committed to not rubblizing concrete at Vermont Yankee. A 2013 settlement agreement with the state says Entergy “shall not employ rubblization at the VY Station site (i.e., demolition of an above-grade decontaminated concrete structure into rubble that is buried on site).”
The Brattleboro-based anti-nuclear group New England Coalition, which has consistently criticized NorthStar's decommissioning plans, claims that NorthStar's rubblization proposal should require the Public Utility Commission to reopen past dockets involving Entergy.
It will be up to the utility commission to decide whether rubblization is acceptable. NorthStar is lobbying hard to preserve the option, but rejection of the concrete-reuse proposal may not be enough to scuttle the Vermont Yankee sale.
“It's an element of our overall proposed approach,” State said in an interview. “In and of itself, as an individual item, it might not be a deal-breaker. [But] it kind of goes hand-in-hand with other considerations.”