LUSBY -- Each looks like an army's ultimate pillbox or a grossly overbuilt garage, surrounded by a double row of high fencing at the Calvert Cliffs nuclear power plant. The exterior walls, made of concrete and steel, are 3 feet thick. So are the roofs. The doors weigh 6 tons.
If all goes well, the new, shedlike buildings will sometime later this year become a storage place for used reactor fuel, by far the plant's most intensely radioactive wastes. Everything at the new depot is designed to endure indefinite amounts of radiation and time, because a truly permanent storage place does not yet exist.
The Baltimore Gas and Electric Co., Calvert Cliffs' owner, has so far spent $24 million on this temporary solution to disposing of wastes that remain deadly for thousands of years -- a problem that, sooner or later, will affect almost every utility with nuclear power plants.
BG&E;'s investment is a sign of the company's desperation: Without the new storage structures, the utility says, it would run out of space for used reactor fuel by mid-1995 and be forced to close the plant.
For $24 million, BG&E; has built the two bunkers and purchased the elaborate equipment required to move spent fuel, as it is called, from the reactor building to the storage site. BG&E; wants eventually to bill those costs to its customers.
It is unlikely to be the final bill.
Every customer of every utility with nuclear power plants is already paying for a federal repository for spent fuel, though the repository does not yet exist. Since 1983, federal law has required utilities to add a surcharge to their bills to help pay the repository's development costs. BG&E;'s customers have so far paid $153 million.
BG&E; offered the Calvert County commissioners a tour of the depot late last year, about the time construction was complete. The local officials noted, without pleasure, the lack of guarantees that the spent fuel will leave the county.
"Realistically," said Commissioner Mary Krug, "I have to accept the possibility that it will be here forever."
"We don't want that to happen," said Hagner Mister, chairman of the commissioners. "I'd like to see the federal government come up with a suitable location for this stuff to go."
BG&E; and its customers are paying the price of broken promises. When the first Calvert Cliffs reactor began generating electricity, in 1975, the federal government was promising to open a permanent disposal site for spent fuel by 1985.
Later, the forecast was changed to 1988. Then, 1998. Then, 2003.
The Department of Energy's current goal is to open a repository at Yucca Mountain, Nev., by 2010. The Nuclear Regulatory Commission (NRC), which must license the site, expresses greater caution; it forecasts only that a repository will become available sometime before 2025, at Yucca Mountain or elsewhere.
Room for expansion
With that history in mind, BG&E; has included room for expansion at the new storage area; unless the company adds still more bunkers, it will again run out of storage space in about 2003. Calvert Cliffs is licensed to operate until 2017, and that license may be extended.
BG&E; has permission to use the storage system for 20 years, but has built structures designed to last considerably longer. "There is no set date at which these things crumble," says Larry Noll, manager of the project. "Given the fact it is essentially reinforced concrete, it can last for an indeterminate amount of time."
What goes into the bunkers is almost certainly destined to outlast them.
Before insertion into a reactor, the long, thin rods that contain Calvert Cliffs' uranium fuel emit relatively small amounts of radioactivity. A person could have a new fuel assembly -- each assembly contains 176 fuel rods -- in his living room, and in a day receive a smaller radiation dose than he would get from a series of hospital X-rays of his chest. He could sit on the assembly for hours, if not days.
Spent fuel is altogether different. When atoms of uranium split during the fission process, more than 100 other radioactive elements are created. The longer the fuel remains in use, the greater the radioactivity. After two years in a reactor, a fuel assembly would be, in every sense, too hot to touch.
Fresh from months or years in a reactor, and exposed to the open air, a fuel assembly would emit a lethal radiation dose in about 10 minutes to a person standing about 10 yards away.
Over time, radiation levels decline. But experts resort to time scales suitable for geology when estimating when spent fuel would no longer pose a hazard. Some of the radioactive material decays into harmlessness in days; other material only after 10,000 years; still other material requires more than 100,000 years.
As did other utilities, BG&E; built its nuclear power plant on the assumption that by the 1990s spent fuel would be an asset instead of an expensive, hard-to-handle waste. With encouragement from the government, the nuclear industry assumed that technology for the recycling of spent fuel would make economic sense and become environmentally acceptable.
None of that has come to pass. The technology, known as reprocessing, is available on a limited commercial basis in other countries but not in the United States, and is beset by political and technical problems. Reprocessing makes plutonium, the key material for nuclear weapons, more readily available and generates still greater amounts of radioactive wastes.
Reprocessing still has its die-hard advocates at Calvert Cliffs.
"Storing these fuel assemblies at the plant, and burying them underground, is not the best way to handle things," says Penney File, principal engineer for fuel management. "No one said, 'Let's build these so they can be used in a reactor for three years and buried for 10,000.' "
Meanwhile, the waste accumulates.
Every 12 to 18 months at Calvert Cliffs, new fuel is loaded into one or the other of the reactors, and spent fuel is carefully maneuvered into a water-filled concrete pool, a standard feature of every nuclear power plant.
Here the pool is 41 feet deep. It contains 600,000 gallons of water, an excellent absorber of radiation. Because of a quirk of physics, the radiation makes the water glow a deep blue.
The pool was designed to hold up to 400 fuel assemblies, each containing about a half ton of uranium. Taken out of the reactor, the assemblies are placed in stainless steel racks submerged in the water. With permission from the NRC, the company on three occasions installed new racks to move the assemblies closer together, to increase the pool's capacity. So the pool can store 1,830 assemblies, instead of 400.
Virtually all that space has been filled. BG&E; says that as early as June, technicians plan to begin moving the oldest, least radioactive assemblies from the pool to the new storage buildings.
Compared to the reactors or even to an automobile, the new storage system is distinctly low technology. It depends on the large, the heavy and the passive. Once the fuel assemblies come to the storage area, the only active mechanism is supposed to be time.
Technicians must begin the transfer by using cranes and robots to maneuver the underwater fuel assemblies into a stainless steel canister, which will be submerged in the pool. Empty, the canister, which looks like a highly polished beer barrel, weighs 14 tons.
Surrounding the canister will be a 70-ton cask. With the fuel assemblies inside, a robot is to weld shut the canister's two-piece lid. It weighs 3 tons. Another 2 tons are added by a bolt-on lid for the cask.
A flatbed truck must carry the cask along about two miles of roadway within the Calvert Cliffs compound to the storage depot. A hydraulic ram will shove the canister out of the cask, off the truck bed and through the bunker doorway into the proper slot. The truck is to make a regular commute: reactor building to storage site, one canister each trip.
If all goes as planned, the storage area will then remain largely out of mind for the next several decades.
BG&E; calculates that, as long as the building and canisters remain intact, the radiation dose to a person living a mile away would be less than one-tenth of the regulatory maximum; at greater distances, the dose would be lower.
Steps are challenged
Not everyone is satisfied with the safety measures. An environmental group, the Maryland Safe Energy Coalition, has asked the NRC to suspend the license for the storage system until the commission considers the risk of a gas explosion from the Cove Point liquefied natural gas terminal four miles south of the power plant.
After keeping Cove Point closed for 14 years, Columbia LNG Corp, its principal owner, has announced plans to reopen the terminal in 1994. Ocean tankers would return to Calvert County, carrying natural gas cooled into liquid form, and transfer the material to the plant for conversion back into a gas.
The NRC has yet to respond to the environmental group's request. But the agency finds nothing wrong with BG&E;'s new bunkers. "Such storage," the commission says in a policy statement, "is feasible, safe and would not result in a significant impact on the environment."
The spent fuel will stay at Calvert Cliffs because, until the federal government develops a suitable waste-disposal site, there is no other practical place to put it. "Our assumption is the repository will be completed," says Mr. Noll, BG&E;'s project manager. "It's just a matter of when."