Entergy seeks 2nd pad to store spent fuel after closure of Vermont Yankee nuclear plant

Entergy Corp., which owns the Vermont Yankee nuclear plant, has asked for permission to build a second concrete pad on which to store spent-fuel casks after the plant closes at the end of the year.

New Orleans-based Entergy announced in August it would shutter the nuclear plant after 41 years. On Monday, Entergy submitted a petition to the Vermont Public Service Board for a certificate of public good, the state utility regulator's final approval.

For the first five years after closure, the spent fuel will be kept in a fuel pool until it cools enough to be moved to dry casks, which are stored on concrete pads on the site. The plant has one pad, and the second could be completed by 2017.

Over the years, radioactivity decreases, meaning there is less exposure to workers and less low-level waste to transport and ultimately bury at an approved site.

A long-debated federal proposal to bury high-level waste at a Yucca Mountain facility in Nevada has gone nowhere, leaving no place to safely dispose of the guts of nuclear power: spent uranium fuel and its byproducts. So, massive dry casks will hold the fuel on the site, secured by guards, for up to 60 years.

When Entergy announced the closure in August, it said there were 13 air-cooled storage casks on the site, containing about 900 spent-fuel assemblies. There are another 3,000 spent-fuel assemblies being held in a water-filled pool that would have to be packed away. The final number that would have to be stored on the site depends on when the Department of Energy begins taking spent fuel.

As proposed, the new pad will be smaller than the existing one, and between the two the plant will be able to store 58 casks, each with 68 spent-fuel assemblies.