A pair of contractors have started cleaning up a University of Washington building contaminated weeks ago by cesium-137, but there is no timetable for finishing the job or reoccupying the Seattle facility.
The contractors are International Isotopes, of Idaho Falls, Idaho, and Chase Environmental, of Louisville, Ky. They are assisting the Washington state Department of Health, the University of Washington, and the Department of Energy’s National Nuclear Security Administration (NNSA) in developing an assessment plan “to ensure effective management of this incident and return the building to full operations as quickly as possible,” a state Health Department spokesperson said by email late last week.
That said, “there is currently no timeline for complete decontamination and reoccupation of the building,” the spokesperson told RadWaste Monitor. The NNSA confirmed that situation this week.
The state agency regulates radiation sources in Washington and had, as of last week, “approved survey and decontamination work on certain floors of the building, which is now underway by the contractors,” the spokesperson wrote.
The state Health Department and the university, along with the NNSA, have formed a unified command to respond to the May 2 contamination incident, in which International Isotopes personnel accidentally broke open a blood irradiator machine containing the highly penetrative gamma emitter.
The first of three phases of work is underway now, the NNSA said Thursday. “During the current phase, Chase Environmental is assessing and cleaning the basement, sub-basement, floors one and three through seven,” the agency said in an update. “Extensive surveys of the surrounding area have also been conducted and no levels that exceed naturally occurring background radiation have been detected. There is no risk to public health.
The second and third phases will involve contracted remediation of the facility’s second floor and loading dock area. The radiation source will be removed and transported to a DOE facility for assessment, the NNSA said.
The Health Department told the Seattle Times that about 200 people will have to be relocated from the University of Washington’s Research and Training Building to other facilities on campus. The relocation will take about a week, and the investigation of the incident could take months, the state agency told the Times.
International Isotopes was removing the machine from under the NNSA-funded Cesium Irradiator Replacement Project, which aims to replace potentially dangerous cesium blood irradiators with X-ray irradiators that serve the same function: sterilizing blood for transfusions.
The accident contaminated 13 people, 10 of whom went to the university’s Harborview Medical Center for treatment and were later released. It also spread contamination throughout all seven floors of the Research and Training Building, the Department of Health has said.
