Advertisement - Click to support our sponsors.
Johnston isle radiation
By Harold Morse
is called tolerable
Star-BulletinA Defense Threat Reduction Agency team has downplayed possible radiation dangers to people or wildlife on Johnston Atoll, site of two nuclear-armed missile mishaps that left some residual weapons-grade plutonium in the immediate environment.
It also minimized or ruled out danger of this radioactive material reaching Hawaii or other Pacific islands on winds or ocean currents.
Its low levels on Johnston Atoll itself would not pose a danger to any other populated areas, and since the material is three times as heavy as lead, ocean currents could never carry it, said John Esterl, senior health physicist, Defense Threat Reduction Agency, Albuquerque, N.M.
The team told an audience of about 45 at Farrington High School that the proposed final soil cleanup level, technically termed "40 picocuries per gram of transuranic alpha-emitting isotopes (plutonium)," poses no real danger to people or wildlife.
The agency provided this information and a justification to the U.S. Environmental Protection Agency; the U.S. Air Force, present custodians of Johnston Atoll; and the U.S. Fish and Wildlife Service, responsible for the Johnston Atoll National Wildlife Refuge. The U.S. Fish and Wildlife Service is scheduled to take over the atoll in 2005.
The next step is final disposition of the material, on which another public meeting will be held here at a time and place to be announced.
Harry Stumpf, Defense Threat Reduction Agency senior environmental engineer, said last night there are eight to 10 options for disposition, including leaving it where it is in the 24-acre radiological control area on the north side of Johnston Island, one of the four islands of Johnston Atoll. Other options would include the more expensive one of removing the contaminated soil and transporting it to a U.S. mainland dump.
Stumpf and others said there is little evidence low dosages or radiation at Johnston Atoll cause any health effects. The level or radiation dosage is about what an airline passenger would be exposed to on two round-trip flights coast to coast, the agency team said.
Radiological material was dispersed over the atoll from two aborted missile launches during high-altitude nuclear weapons testing in 1962. Cleanup efforts have been ongoing since then.
An "acceptable level of concentration" of weapons-grade plutonium remains, said Kathryn Higley, associate professor of radiation health physics, Oregon State University, under a research contract for Johnston Atoll assessment.
The atoll, located 825 miles southwest of Honolulu, became a national wildlife refuge in 1926 and came under Navy jurisdiction in 1941. More recently, it has been the site of chemical weapons incineration.
The Army's Johnston Atoll Chemical Agent Disposal System is scheduled to phase out with closing procedures beginning in January. Over the past 10 years, more than 3.8 million pounds of chemical weapons have been destroyed.
