As the nuclear crisis in Japan worsened, the job of averting a catastrophic release of radiation has fallen to 50 emergency workers at the Fukushima Daiichi nuclear facility.
At least 15 workers have been injured in explosions at the facility.
As the explosions have continued, and radiation levels have spiked, roughly 800 employees have been evacuated. Among the tasks for those who remain: pumping seawater into the three failing reactors to keep the nuclear fuel from melting down. A fire at a fourth reactor provided them with another challenge.
“If they exceed a certain amount, they can’t go back in for a day or a week or longer,” Dr. Lew Pepper, a professor at the Boston University School of Public Health, told the New York Times. Pepper, who has studied the effects of radiation on nuclear weapons workers, said the pool of available replacement workers is finite.
The nuclear plants’ operator, Tokyo Electric Power, has declined to provide details about the workers.
Arnold Gundersen, a consultant who worked in American plants nearly identical to the stricken Japanese ones, told the Times it was likely that the company was calling in retirees and workers from unaffected plants for help. And perhaps for sacrifice, as well. “They may also be asking for people to volunteer to receive additional exposure,” he said.
Japan’s Ministry of Health, Labor, and Welfare has raised the exposure limits for workers battling the disaster, according to Japanese sources quoted by the Monthly Review. The new limit of 250 millisieverts is 2.5 times the previous limit.
Gamma rays and other penetrating radiation can cause cancers and other illnesses and death.
While regulations may differ somewhat in Japan, in the United States the usual radiation exposure limit for nuclear power plant workers is 50 millisieverts, or 5 rem, per year (compared with the 0.3 rem that the Environmental Protection Agency says most people get from normal background radiation).
The explosion at Fukushima’s Reactor No. 2 on the morning of March 15 sent radiation levels spiking, to 8,217 microsieverts an hour from 1,941 about 40 minutes earlier. Later in the day, Japanese nuclear officials announced much higher levels and evacuated most of the emergency workers, according to the Times.
Those workers who remain are doing so at great personal risk in an effort to shield the rest of the population from a potentially catastrophic radioactive release.
Japan’s Fukushima Daiichi Unit 1 reactor, one of those that exploded, is a General Electric Mark 1 boiling water reactor type. There are 23 GE Mark 1 reactors operating at U.S. nuclear power plants. All but one of these 23 reactors has received a 20-year license extension from the Nuclear Regulatory Commission, or has such an extension under review by the Nuclear Regulatory Commission. None of the 23 is located in California.