Nuclear Plant's Waste Problem Looms At Lakeside

January 25, 1993|By Stevenson Swanson, Environment writer.

COVERT, Mich. — On the eastern shore of Lake Michigan, next to the Palisades nuclear power plant, a row of 16-foot-tall concrete cylinders stands on a slab just 150 yards from the water.

Those cylinders are the key to the plant's future. If its owner, Consumers Power Co., is allowed to use them to temporarily store used radioactive fuel rods, the plant will be able to refuel and keep operating. If not, it will have to shut down in June, turning off almost a quarter of the utility's capacity to generate electricity.

But Michigan environmentalists fear that the storage would not be just temporary. And eventually, they say, the concrete casks might crack open and leak radioactive debris into the Great Lakes, the drinking water source for 23 million people.

Palisades, one of the nation's oldest nuclear reactors, is facing a problem that an increasing number of America's 110 nuclear plants will encounter in coming years.

It is almost out of space for its old radioactive fuel rods, which have been accumulating in a special pool of water inside the plant since it started generating electricity in 1971.

There is still no long-term solution to the storage of nuclear power plant waste, which will remain dangerously radioactive for thousands of years. And while the federal government searches for one, the rods are piling up.

Consumers Power says that without the cylinders, it will have no place to put the rods that are due to be removed from the reactor in June.

Utility spokesman Mark Savage said the utility no more wants the used fuel to stay at the plant site than the environmentalists do.

"It's a necessary evil to keep the plant running," Savage said. "We don't want the fuel here. We at Palisades are a symptom of the larger problem, and we are not alone."

The larger problem stems from the federal government's failure so far to find a permanent answer to the nation's nuclear fuel quandary.

At one time, the government intended to reprocess old fuel so it could be reused, but President Jimmy Carter canceled those plans because of concerns that terrorists would steal reprocessing by-products and manufacture nuclear weapons.

In 1982, the government promised to build a repository where all of the nation's spent fuel rods could be dumped safely, but the U.S. Department of Energy has run into stiff opposition and technical problems in its attempts to build such a facility at Yucca Mountain, Nev.

That has meant that each utility must fend for itself and find ways to hold more and more old fuel on site while waiting for the federal government.

At first, Consumers Power bought time the way that many other utilities have, including Commonwealth Edison, which has more nuclear reactors than any other utility in the country.

By rearranging the racks that hold old fuel-rod assemblies in the plant's spent-fuel pool, Palisades was able to increase its storage capacity to 892 assemblies from 272.

Each assembly is a bundle of fuel rods about 12 feet high and 8 inches square.

"Re-racking," as the process is called, will give Edison's 12 reactors breathing room until at least 1997, when one of two units at the Zion plant will run out of space.

At Palisades, only 24 empty slots remain. When it refuels in June, it will need space for 68 old fuel assemblies, or else it will have to shut down.

Last summer, a contractor built eight concrete cylinders, with 29-inch-thick walls, to hold old fuel rods. Similar systems, called "dry-cask storage," are in use at or planned for reactors in Virginia, South Carolina, Wisconsin and Colorado.

But the design of the Palisades casks, which cost $500,000 each, is different from those already in use, and so must be certified by the Nuclear Regulatory Commission as safe before any utility can use it.

If Consumers wins approval, it will remove 48 of the oldest, least radioactive fuel assemblies in its storage pool and place them in two casks. First, the fuel assemblies will be loaded into a metal basket, which will be placed inside a steel cylinder that will be welded shut. That steel cask will then be lowered into the concrete cyliner, which will be sealed shut.

Each concrete cask will weigh 130 tons when loaded and is said to be able to withstand earthquakes, tornadoes, and even an automobile traveling at 126 miles per hour.

Ventilation ducts in the outer concrete casing are designed to allow heat to escape and keep the rods from overheating and melting. But because of the thick casing, Savage said, a human who stood next to the cask for one hour would receive the same radiation as he would from a chest X-ray.

"One of the benefits of the dry casks is that there are no moving parts," Savage said. "It is absolutely the most uncomplicated thing we have in our business today. In the spent-fuel pool, you're relying on pumps and filters and heat exchangers, but this is a passive system."