SAN ONOFRE, Calif. - A large trailer was set Tuesday to carry the first of four old steam generators from the San Onofre Nuclear Generating Station to a disposal site in Clive, Utah.

The 399 foot long, 20 foot wide, trailer with 192 tires is only expected to go about 15 miles per hour on the road. With the destination 830 miles away, the trip is expected to take about three weeks.

"It is unusual in its size," said Craig Harberts, Edison's Project Manager. "In the heavily populated areas, we will be travelling at night with CHP escort."

It was specially designed about a year ago in Minnesota by Perkins Logistics and Specialized Transportation, according to Edison.

There will also be a security detachment, as well as officials with Edison travelling with the generators.

The generator itself weighs about 380 tons. Edison officials said the generators are classified as low-level nuclear waste, and well within safe levels.

"If you were to stand approximately six feet away from the lower assembly itself for an hour, you would pick up approximately what you would receive in a dental x-ray," said Harberts.

Officials with Edison only gave a few details on the route because of security reasons, but said the trip will begin heading south toward Oceanside.

"It will then transit across to Interstate 15, and that's when we will begin the trip north," said Harberts.

The route also includes heading toward Temecula, taking back roads to Highway 395 until they reach Nevada, then onto Highway 6 until they reach Interstate 80 on the way to Utah, said officials.

"We have designated areas where we can safely pull off to the side of the road, people can get around us, and traffic can flow normally," said Harberts

Workers at Edison had to separate the generator's lower assembly from its steam dome in order to carry it to Utah. According to Edison, the "steam domes" will be disposed of as scrap metal, or if they contain very low levels of radioactivity, will be sent to the same facility in Utah.