The Next Step

CP&L already has two fuel rod storage pools in use at its nuclear power plant in Wake County and has applied to the Nuclear Regulatory Commission to activate two more.

Plant officials say they have added safety measures to reduce the risk of an accident.

But the highly radioactive nature of the rods has some residents up in arms about CP&L's proposal, said Gordon Thompson, executive director of the Institute for Resource and Security Studies and an adviser to Orange County.

"Essentially, Orange County is saying the pools are a dangerous way to store spent fuels."

This is where dry storage comes in. Officials say using dry storage casks is preferable to wet pools because they would eliminate the need to bring reactor waste to Shearon Harris.

"We're very much in favor of dry storage at each generating reactor instead of bringing it to Harris," said Jim Warren, director of the N.C. Waste Awareness and Reduction Network.

"The waste is coming from CP&L's other reactors in North and South Carolina. If (CP&L) chooses to do dry storage, they'd drop the plans to import the stuff here."

Dry casks allow each reactor to dispose of its own waste safely. A cask is put into the pool so that water can drain in. Fuel is then moved into the cask. Once the cask has been filled, it can be removed and stored elsewhere.

David Lochbaum, nuclear safety engineer for the Union of Concerned Scientists, said casks not only provide all of the safety measures of pools, but have added benefits, such as the ability to be moved, even while their contents are radioactive.

"In a wet pool, the fuel is stored in water, which absorbs the heat and shields the workers," he said. "In dry storage, the convection of air is used to remove the heat. For shielding, the cask is made of lead and concrete, so you can touch the outside of the cask and not risk radiation. The casks can then be shipped to wherever the United States decides to store them ultimately."

Using the wet pool method, the spent fuel would have to cool for 10 years before it could be stored above ground, and then by using the same steel and concrete protection as a dry cask. The rods could not be moved immediately to a permanent repository.

Warren said the potential risks of dry storage are minimal compared to the possibility of an accident with wet pools. He compared the degree of severity between the two methods to the difference between a hand grenade and an atomic bomb.

"An accident with dry storage would be bad, but the greatest potential threat would be far less than the greatest potential accident by a wet pool," he said.

Lochbaum said a wet pool accident might set off a dangerous chain reaction.

"In dry cask storage, if something was to happen, the consequences would be contained in one dry cask. There is no domino effect," he said. "In a spent-fuel pool, if the water drained out and a fuel rod overheats and starts melting, the temperature would be enough to catch the pool on fire, which would cause other fuel rods to undergo the same effect."

Lochbaum said Shearon Harris is in better condition than older plants because it had been built with spent fuel storage in mind, but problems with pools could still arise.

"The biggest advantage (of dry casks) is that there are no moving parts - not much can go wrong," he said.

"In the pool, there is a number of systems that have to be operating in order for the public and workers to be protected."

Lochbaum said the two main problems with pools are that they can crack and water can drain out and that the cooling system could stop working and the water would boil off, leaving no water to protect the fuel rods.

But Jeanne Bonds, corporate communications manager for CP&L, said dry casks are not safer than wet pools.

"CP&L believes that both options are equally safe," she said. "We have additional pool storage, and our employees have been trained and are knowledgeable with it."

Shearon Harris also already has installed safety precautions to ensure against the kind of accidents that worry Lochbaum, said Ed Willis, manager environmental and radiation control.

"The pool is 40 feet of water with walls of reinforced concrete six to 10 feet deep, lined with stainless steel and has a seismically designed roof," he said. "It's designed to stand up against earthquakes, tornadoes and hurricanes.

"We have two independent safety-related cooling systems. If one goes down, there's a backup. They're hooked up to separate power sources and there are no drains, no way for the water to get out."

The City Editor can be reached

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