Yankee uprate effects at issue

June 17, 2003

By SUSAN SMALLHEER Southern Vermont Bureau

MONTPELIER — Increased power production at Vermont Yankee nuclear power plant will mean increased radiation and increased environmental impacts outside the plant, the state’s nuclear engineer said Tuesday.

William Sherman, the engineer with the Department of Public Service, admitted under questioning from the New England Coalition that any increase in radiological releases would have an environmental effect, and that there was no such thing as an increase with no effect.

The increased radioactivity, about 28 percent above current levels, would still be within state limits of 20 millirems per year, Sherman stressed.

Sherman said that when coupled with increased radiation coming from a new treatment process the plant was on the verge of re-employing, the state’s maximum would be all but reached.

Entergy Nuclear wants to increase power production at Vermont Yankee by 20 percent, or 110 megawatts of power at a plant that on average produces 510 megawatts of power.

The Public Service Board must grant Entergy Nuclear a certificate of public good for the construction project, which is estimated to cost at least $60 million. Federal regulators must also approve the project.

The board also heard Tuesday from an aesthetics consultant for Entergy Nuclear who said the steam plume rising from the plant’s 22 cooling towers would be significantly bigger and taller, 25 to 27 percent bigger, than current plumes that rise from the plant’s 22 cooling towers.

The proposed 20 percent increase in power will general more power — and heat — that has to be dissipated through a variety of ways. The internal core temperature of the reactor core will not change, despite the additional fuel.

The state has a higher standard, but lower dose, for radiological releases from the plant than the federal regulars have imposed. The federal standard is 25 millirems, while the state standard is 20 millirems, something that was negotiated when the plant was built more than 30 years ago.

Last winter, Entergy had considered asking the state to raise the standard, but it dropped the request quickly.

Sherman said the hydrogen gas and noble metals treatment was adopted initially at Vermont Yankee more than a year ago, but temporarily abandoned because it is suspected to have contributed to the leaking nuclear fuel in the reactor core last year, which caused the plant to shut down for repairs. That hydrogen process also means additional radioactivity released, he said.

Yesterday, Entergy Nuclear Vermont Yankee vice president Jay Thayer said the 20 percent power increase would result in up to a 28 percent increase in radiation.

But Raymond Shadis, staff member of the New England Coalition, a Brattleboro-based anti-nuclear group, pointed out inconsistencies in Thayer’s estimates.

Citing different testimony, Shadis noted that Thayer said 28 percent on Monday, but in written testimony in April had estimated the increase at less than 20 percent, and at one point he quoted 22 percent in internal office e-mails. The actual increase is estimated between 3.6 to 4 millirems.

“Entergy’s numbers are all over the place,” Shadis said.

Sherman said that according to his calculations, the additional 110 megawatts should cost about 2 cents per kilowatt hour, far below the previous owners’ costs per kilowatt at Vermont Yankee or 4.5 to 5 cents.

Sherman and three consultants hired by Entergy Nuclear to study the environmental effects of the plan testified Tuesday.

Consultant Eric Dodson said that the maximum plume would come in the spring and fall, with the plume reaching lengths of 500 meters and heights of 100 to 110 meters.

Dodson said he had to redo his earlier report because Entergy Nuclear had changed the size of the fans it would use to dispel the steam, from 200 horsepower to 125 horsepower.

Dodson downplayed the impact of the large white cloud that would rise from the plant’s cooling towers, comparing it at one point to Old Faithful , a steam geyser in Yellowstone National Park .

Under questioning from Chairman Michael Dworkin, Dodson admitted that Entergy had abandoned the most powerful mitigating factor — the larger fans — to keep the steam plume smaller. And Dodson admitted he hadn’t determined the full aesthetic impacts with the smaller fans.

Testimony in the case will resume Thursday.

Contact Susan Smallheer at susan.smallheer@rutlandherald.com.