SAN ONOFRE -- When Southern California Edison finally hauls its retired nuclear reactor vessel around Cape Horn at the tip of South America to an underground disposal site in South Carolina -- perhaps as soon as this month -- it will be the longest ocean voyage ever for a piece of low-level nuclear waste.

The trip will take a container of radioactive concrete and steel through one of the world's roughest ocean passages and runs the risk of offending several South American countries.

"It would clearly be the longest … but they ship much, much, much larger packages than that around Cape Horn all the time," said John Vincent, senior project manager for the Nuclear Energy Institute in Washington, D.C.

For now, the radioactive reactor vessel, a kind of carbon steel kettle built to contain the furious heat of nuclear fission, sits quietly in a giant steel container that looks like the world's largest thermos.

Since 2001, Edison, the San Onofre Nuclear Generation Station's majority owner and operator, has sought to send the radioactive containment vessel to Barnwell, S.C., for burial in a graveyard for low-level nuclear waste. There are no such facilities that will accept the package on the West Coast.

In its current thermos bottle package, the vessel is designed to dampen radiation leakage to acceptable levels. Edison officials have said that a person sitting atop the tan containment vessel for one hour would receive a dose of radiation equal to half a chest X-ray.

Earlier this week, Edison received a permit from the U.S. Department of Transportation to ship the 770-ton capsule to Barnwell via South America. Edison's plan is to load the behemoth aboard a barge named the "Paul Bunyan" and use an ocean tug to haul it 13,000 miles around Cape Horn Chile through an international shipping lane known as Drake's Passage.

Thus far, Edison has been mum about exactly when the odyssey will begin.

Ray Golden, Edison's resident spokesman at San Onofre, said Friday that it's too early to say exactly when the equipment, personnel and environmental conditions will all be in perfect alignment.

"It could happen within the next few weeks or as late as March 2004," Golden said.

Skepticism remains

Some, such as Tom Clements of Greenpeace International, call Edison's impending voyage around Cape Horn no different than dumping trash in your neighbor's back yard.

"It's a typical 'dump it on somebody else and don't worry about it anymore' response," Clements said.

Greenpeace filed a formal complaint with the Department of Transportation, demanding that the agency force Edison to complete another round of environmental studies before moving the reactor vessel. He noted that, though Edison studied how the reactor core might affect natural habitat on land, it did not do so for the long stretch of ocean it will pass over.

"As far as I'm aware, there has been no environmental study done for international waters," Clements said. "The public has been given no chance to comment."

When the journey does finally commence, it will start with a 17-mile drive south from San Onofre to Oceanside Harbor.

A crane will load the 770-ton package aboard a special 16-axle transport trailer with 192 tires. The trailer is pulled by a "prime mover" semi-trailer. Together, the prime mover, transport trailer and reactor package top 900 tons.

On the day of departure, the transport vehicle will pull the heavy trailer south down a frontage road that parallels Interstate 5. Once the procession reaches Skull Canyon just south of the Las Pulgas Gate at Camp Pendleton Marine Corps Base, the journey must change paths, moving through the slow lane of I-5 for about a quarter of a mile.

"That part will probably happen at 4 or 5 in the morning," Golden explained.

He added that Edison has reinforced the frontage road and the freeway where necessary to make sure the reactor vessel's ponderous bulk does not leave a path of cracks and potholes in its wake.

Once past Skull Canyon, the reactor and its transport will veer off the freeway, slicing diagonally onto Red Beach at Camp Pendleton. There it will roll onto a custom-built, temporary roadway along the beach made of interlocking rubber mats. Crews will lay a mile of mats along the beach, continually removing those that have already served their purpose and laying them down again to extend the path south in a hopscotch fashion.

Golden said the transport vehicle should move at 2 to 3 miles per hour on paved ground and slower over the beach, meaning the entire trip to the harbor will take between five and seven days.

To receive permission to drive across the beach and through part of the San Onofre State Park, the California Coastal Commission required Edison to take pains to avoid damaging the environment. The trip is scheduled for the winter to avoid the nesting seasons of the western snowy plover and the California least tern. A biologist will travel with the package from start to finish, to make sure the path does not harm native plants or animals.

"The biologist can stop the whole thing at any time if he finds a problem," Golden said.

When the package arrives at Oceanside Harbor, it will be trucked to a dock in the Del Mar Boat Basin, which is operated by Camp Pendleton, where the barge will be pulled alongside a pier.

A crane will load the oversized canister aboard the barge, where it will be bolted and welded in place. The U.S. Coast Guard and the Nuclear Regulatory Commission must inspect the installation to make sure it's secure, then an ocean tug will tow the Paul Bunyan out to sea. A second companion tug will travel with the first tug, making three trips to shore to retrieve diesel fuel and supplies.

The trip from Oceanside to a dry dock in Charleston is expected to take 90 days and will travel through some of the most treacherous waters in the world. Though modern shipwrecks are rare, the passage has claimed hundreds of vessels over the centuries. Because fierce weather and monstrous waves are a reality in the seas near Cape Horn, it is conceivable that the voyage might require safe passage in one of the countries that border the route -- most likely Chile and Argentina.

Golden said Edison's shipping plans call for the barge to remain in international waters at all times, though an emergency could force captains to seek shelter in the territorial waters of a neighboring country such as Chile or Argentina. Those countries have a history of resisting any attempt to bring any kind of nuclear waste within their boundaries, so finding a safe harbor in a storm could be difficult.

Should the barge sink, Golden said Edison engineers estimate that the container could survive on the sea floor for 500 years without irradiating the surrounding marine environment. He said Edison also carries a $50 million insurance policy to salvage the canister if the barge sinks.

"There has been some question about whether we can salvage in deep water," Golden said. "We have examined the depth of the water all along the path and we are confident we can salvage that deep."

Once the voyage clears Cape Horn, it must chug north all the way to Charleston. Golden said that Edison's transit permit allows the company to unload the canister from a privately owned dry dock and onto a specially designed railroad car for a 120-mile trip inland to Barnwell. Golden said getting the reactor vessel from boat to train is the one area where the trip could still be delayed.

"We already have the permit to unload it, but we need the OK from the dry-dock owner. It's just a verbal type of approval, but if we didn't get it, it could be a problem," Golden said.

It will cost $10 million to transport the retired reactor to its final resting place. The expense is paid for by a surcharge added to electric bills for all of Edison's customers. All told, decommissioning the power plant will cost $600 million.

Edison tried to transport the reactor to Barnwell over the national rail network but was unable to reach agreement with the a freight company regarding legal liability if there was an accident. Likewise, the concrete-and-steel package was deemed too heavy to travel through the Panama Canal.

Contact staff writer Paul Sisson at (760) 901-4087 or psisson@nctimes.com