Nuclear Regulatory Commission faults flood-prevention measures at Vermont Yankee

Last modified: Thursday, March 20, 2014
BRATTLEBORO, Vt. — An audit conducted by the Nuclear Regulatory Commission of Vermont Yankee’s post-Fukushima flood-prevention measures has found Entergy Nuclear’s effort lacking.

In a report released recently, the NRC found there were several instances of Entergy not following directions on the post-Fukushima requirements to conduct a visual reassessment of its flood-prevention measures. NRC also faulted missing information and improperly performed calculations.

While Vermont Yankee is built on the banks of the Connecticut River, its location above the river is estimated to be at the 500-year flood level. But flooding can come from more common sources. Just in the past year, Vermont Yankee has had problems with missing flood seals, which allowed standing water to seep into underground equipment.

“This was not an inspection, it’s an audit designed to find out whether the guidance was faithfully followed,” said Neil Sheehan, a spokesman for the NRC.

“As has been the case at other plants, our audit team developed several observations on areas where Vermont Yankee did not include certain necessary information in walkdown reports or failed to properly perform calculations,” he said last month.

Sheehan said that since it was not an inspection, there are no violations, but that the audit team found problems or areas of concern. He said the inspection was conducted in July 2013. Entergy Corp., announced in late August it was closing Vermont Yankee at the end of 2014, when the current load of nuclear fuel was exhausted.

Sheehan said that the NRC remained vigilant regarding any change in effort or emphasis at Yankee, pending its shutdown. But he said that some nuclear reactors that are not scheduled for shutdown had the same problems as Yankee.

The Fukushima nuclear disaster, which occurred almost three years ago, prompted the NRC to order many reviews or changes at nuclear power plants in the U.S. Those include some special requirements for reactors similar to those used at Fukushima which were designed by General Electric. Vermont Yankee, a boiling water reactor, is one of those 23 plants.

Entergy Nuclear spokesmen did not return a request for comment on the findings of the audit team.

Sheehan said that much of the post-Fukushima flooding hazard re-evaluation will be moot for Vermont Yankee which expects to be offline by the end of the year.

“In the case of Vermont, at the end of the year, a lot of these requirements become moot. In the interim, we expect the plant to protect against severe flooding,” Sheehan said.

According to the flooding hazard evaluation, the NRC six-member team, which included one of the NRC’s resident inspectors at Vermont Yankee, found “potentially imprecise or vague language” in Entergy’s own procedures regarding the placement of protective sandbags.

Entergy replied that the information the NRC was seeking was not contained in the procedure, but that the plant intended to barricade the equipment in the switch-gear rooms, and fuel-oil storage tank and enclosure.

The audit team found other missing information in Entergy’s flood hazard review procedures.