York, PA - A former Three Mile Island Unit 2 supervisor has projected that not one person will die as a result of radiation exposure from the damaged Fukushima Dai-ichi Nuclear Power Station in Japan.
The number of workers struggling to cool the plant's three crippled reactors and pool filled with spent fuel assemblies are limited, reducing the number of people exposed to the most harmful radiation, said Dick Dubiel, who now consults for the nuclear industry.
Also, most of the people in the area around the plant have either evacuated or died from either the earthquake or tsunami that struck Japan on March 11, he said.
"If there would still be people, that would mean that the tsunami didn't wipe out the whole area," Dubiel said. "That would mean they would have likely been able to get some kind of help in there such as generators to keep the pumps going."
At the time of the TMI Unit 2 partial meltdown on March 28, 1979, Dubiel supervised the plant's radiation, protection and chemistry program.
Joseph Mangano, executive of the New York-based Radiation and Public Health project, said he agrees radiation levels are highest near a reactor and that the threat of serious contamination does decrease the farther away a person stands from the plant.
"Radioactive gases do dissipate the farther they travel," Dubiel said.
However, that's where the two men stop agreeing.
"Without a doubt, I believe that people will become sick and die from radiation exposure because of this event," Mangano said. "All doses of radiation carry a risk. The workers at the plant are in considerable danger."
Workers at the Fukushima Dai-ichi plant are now limiting their radiation dose to an amount that would equal 25 rem per year, or a dosage that humans are typically subject to only in emergency situations, said Dubiel, co-owner of Atlanta-based Millennium Services Inc., a firm that provides radiation safety consulting services to the nuclear industry.
In United States, plant workers are usually subject to five rem a year, according to the U.S. Nuclear Regulatory Commission. A rem is a measure of radiation, and a single dose of 500 rem would kill a human.
Since the earthquake and tsunami, experts from around the world have offered different takes on the long-term effects of radiation dangers posed by the Fukushima Dai-ichi plant.
"At this point, there is still no evidence that there's been significant radiation spread beyond the immediate zone of the reactors themselves," stated Michael O'Leary, a representative of the World Health Organization, in a Reuters article Friday.
The International Atomic Energy Agency posted to its website Friday that "contrary to several news reports, the IAEA to date has not received any notification from the Japanese authorities of people sickened by radiation contamination."
No power
In the case of Fukushima Dai-ichi, the plant seemed to have survived the earthquake, Dubiel said.
However, the powerful tsunami that followed destroyed the plant's infrastructure that it used to pull in offsite power -- energy needed to run the coolant pumps that circulate water through the reactor, he said.
The plant's back-up diesel generators took on water and soon failed. The plant was able to run on battery back-up for roughly 10 hours.
"That should have been more than enough time" to get a generator to the site, Dubiel said. "However, the damage from the quake and tsunami prevented plant workers from getting any back-up generators. Now, you're starving cooling water to the core. You are doing that to three operating reactors."
During the 1979 accident at TMI Unit 2, when about half of the reactor's fuel liquefied, the plant never lost offsite power, Dubiel said.
"At TMI, we had all of our instrumentation to tell us what the pressure was inside the reactor vessel," he said. "We knew that we wouldn't over pressurize and lose integrity of the vessel."
At Fukushima Dai-ichi, the lack of power has prevented workers from monitoring pressure, Dubiel said.
"You walk into control room, and everything is dead," he said.
To relieve the pressure of the buildup of steam and gases in the reactor, workers at the plant in Japan vented the vessel -- an action that eventually caused hydrogen to mix with oxygen, resulting in at least of the site's recent explosions.
Lessons are 'months away'
Exactly how much energy companies, domestic and foreign, take away from the crisis in Japan is largely unknown.
"All of the lessons that are going to be learned are months away," Dubiel said. "There will be lessons learned on topics such as emergency equipment and design."
Mangano said it's possible that the nuclear emergency happening in Japan could befall a reactor in the United States.
"It's impossible to anticipate an unprecedented severity in acts of nature," he said. "There should be a thorough review of our plants' preparedness for extreme acts of nature and our ability to respond to them."
David Tillman, spokesman for the Peach Bottom Atomic Power Station, said his plant and all Exelon Nuclear plants, including TMI, are designed to American seismic and flood standards that reflect their local geography.
"The plants are equipped with numerous and redundant safety systems designed to protect the sites from earthquake, flooding and other natural disasters," he said.
More requests for KI pills
More people are calling the Pennsylvania Health Department to obtain a pill that could ward off thyroid cancer in the event of exposure to radiation, officials said.
The pill, potassium iodide, protects only the thyroid from radioactive iodine, said Dr. Glenda Cardillo, public health physician for the department.
The tablets serve no other purpose, she said.
The department usually hands them out to people who live within 10 miles of Peach Bottom Atomic Station and Three Mile Island. Residents there have to call 1-877-PA-HEALTH to receive their medication, said Jeff Blystone, acting director of community health studies.
Usually, the department gets about five to 10 calls a week requesting the pills. Since the tsunami damaged the Fukushima Daiichi power plant in Japan on March 11, the agency had received about 85 calls about potassium iodide as of Wednesday, Blystone said.
Many of the calls came from people who have discovered their supplies had expired, Blystone said.
Japan plant hits TMI level
An international agency rooted in nuclear safety standards and technology has ranked the crisis at the Fukushima Dai-ichi Nuclear Power Station in Japan to be on par with the 1979 partial meltdown at Three Mile Island in Dauphin County.
Japanese authorities have notified the International Atomic Energy Agency that core damage at Fukushima Dai-ichi's Unit 2 and Unit 3 reactors now ranks as a level 5 on the agency's international nuclear and radiological event scale.
A level 5 event means that an accident with wider consequences has occurred, according the agency's website, www.iaea.org.
In terms of the effect on the public, the plant in Japan is releasing a limited amount of radioactive material that is likely to require the country's emergency operations to take countermeasures. The agency ranks TMI Unit 2's partial meltdown as a level 5 based on the fact that the accident resulted in "severe" damage to the reactor's core.
Also of interest
· Three Mile Island emergency indelibly written into memories.
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