HARRISBURG, Pa. - Radioactive dust unexpectedly blew out of a pipe being cut by workers during weekend maintenance at the Three Mile Island nuclear power plant, and officials were trying yesterday to determine exactly how and why it happened.
The accident at the central Pennsylvania plant - the site of the nation’s worst nuclear power plant disaster - exposed a dozen employees to radiation, but the public was in no danger, plant officials and government regulators said.
Plant officials likened workers’ maximum exposure to the equivalent of two medical X-rays, while the US Nuclear Regulatory Commission said the workers were exposed to a small fraction of the annual federal regulatory limit.
“We are back to work and back to normal right now,’’ plant spokesman Ralph DeSantis said.
The accident happened at about 4:15 p.m. Saturday. A radiation monitor at an entrance to the reactor building “temporarily went up’’ slightly, but a later survey detected no contamination outside, DeSantis said.
About 150 workers in the reactor building were sent home, and plant officials contacted authorities a few hours later and decontaminated the building.
Any radiation on an external surface, such as a safety suit, can be cleaned off, while it takes two to three days for radiation to naturally leave the body of anyone who breathed it, DeSantis said.
The plant, which is on a Susquehanna River island near Harrisburg, has two reactors. One suffered a partial meltdown in 1979 and remains mothballed. The other, owned by Chicago-based
DeSantis said workers were cutting cooling system pipes when a change in the air flow stirred up radioactive dust.