The Department of Energy, the manager of its Los Alamos National Laboratory, and an on-site contractor all shoulder some blame for a May 2019 incident that contaminated a University of Washington building in Seattle with cesium-137, according to a recent report.
The “preventable” event during a radiological source recovery operation resulted from “weak and partially implemented processes within” the Energy Department, lab prime Triad National Security, and International Isotopes, according to the March 30 report from a joint investigation team [JIT] of personnel from DOE’s semiautonomous National Nuclear Security Administration (NNSA) and Triad. “These weaknesses established conditions where the event was likely to happen. The JIT views this event as a near miss to a significant event in that only a small amount of the 2900 curies of cesium was released.”
NBC affiliate KING 5 first reported the investigation’s findings on Tuesday.
“The cesium contamination at the University of Washington’s Harborview Research & Training facility was an unprecedented incident that has posed unique challenges during the response, recovery, and cleanup,” the NNSA said in a statement Friday. “Since 2009, NNSA has removed 350 cesium irradiators and this was the first and only incident of contamination as part of this important national security mission. In this joint investigation, NNSA has taken an unflinching look at the incident to determine the direct, contributing, and root causes of the breach of the cesium source.”
The agency said it is taking a number of corrective steps to address the failure, including a temporary suspension of recovery operations that invovle removing the source and transferring it within a shielding cask, along with a safety review to identify and address any vulnerabilities in its source-recovery operations.
International Isotopes, an Idaho-based radiological source recovery specialist, was removing a blood irradiator with a 2,900-curie cesium-137 source from the Harborview Training and Research Facility on May 2 ,2019, under contract to Triad. The irradiator did not fit exactly right into the mobile hot cell the company brought along to safely remove the device’s cesium source, and when International Isotopes personnel decided to go ahead with the job, anyway — cutting into the source with a saw to unseal it — the device leaked radiation.
The subsequent release of gamma radiation-emitting cesium-137 contaminated 13 workers and observers at the job site, and seven floors of the building. The running total for the ongoing cleanup is $30 million and counting. The incident prompted International Isotopes to exit the radiological source removal business after DOE canceled or suspended all of the company’s contracts for such services.
The irradiator’s cesium-137 was harder to access in part because of the NNSA’s in-device delay program, the report says.
After the Sept. 11, 2001, terrorist attacks on the World Trade Center in New York and the Pentagon near Washington, D.C., the NNSA created the program to collaborate with irradiator manufacturers and, loosely speaking, armor up the devices. The idea was to make it harder for a bad actor to access a gamma-emitting source and use it as a radiological dispersal device — a so-called dirty bomb.
It also had the unintended effect of preventing the irradiator from sliding into International Isotopes’ mobile hot cell in the expected position during the incident, the report says. The remnants of the in-device delay kit “were interfering with the expected alignment,” according to the report.
With the irradiator cocked unexpectedly in the hot cell, International Isotopes personnel had to use the system’s remote-controlled arms to get at the cesium source from an odd angle. It also prevented operators from putting the hot cell’s “donut shield” in place. The shield is supposed to block radiation from escaping the cell, according to the report. Eventually, however, the device did fit into the hot cell, and International Isotopes personnel decided to proceed with the source removal.
Despite the unusual alignment of the irradiator in the hot cell, company personnel did not discuss “the potential for a contamination event,” according to the report.
If the remnants of the irradiator’s in-device delay kit had been removed, and the irradiator had been inserted into the cell “in the originally planned configuration, this would [have] allowed use of the donut shield [and] have prevented the subsequent radiation stream in the direction of INIS Employees and observers,” the investigators determined.
The report says the University of Washington lost confidence early in International Isotopes’ ability to deal with the aftermath of the spill. The university itself was ill-suited to oversee a cleanup of this scope, investigators stated.
The week of the contamination, the university “attempted to seek DOE assistance through several channels, including the Washington Governor’s office, Washington State Senate and House of Representative Offices, and colleagues in the University of California system.” On May 13, 2019, a week and a half after the incident, senior NNSA leadership and Los Alamos Director Thom Mason notified the university that they would step in and helm the response.
Steve Laflin, president and CEO of International Isotopes, did not reply to an email seeking comment on Thursday. The accident has so far cost the company about $2.5 million, much of which it has recouped through insurance. In its 10-Q filing with the Securities and Exchange Commission this week, International Isotopes said it should receive full indemnity for the accident from the Energy Department.
Triad National Security also took some flack in the report. The NNSA said the Los Alamos prime should have made sure that International Isotopes practiced the lab’s strict safety requirements in the subcontracted work. Triad was concerned about “directing subcontractor work and incurring corporate responsibility” for International Isotopes’ actions, the report says.
“The Triad contracting process does not implement Integrated Safety Management (ISM) for offsite work (i.e., outside LANL),” the report says. “The environmental, safety, and health hazards for this activity were not reviewed or understood by Triad safety and operations personnel.”
In addition to telling Triad that it needed to flow its own safety standards into off-site contract work, the report says NNSA headquarters, through the Global Threat Reduction Initiative in the Defense Nuclear Nonproliferation office, should evaluate how all agency management and operations contractors are overseeing their off-site subcontractors.
The NNSA beat up Triad a little over the mishap in the company’s first performance evaluation, docking the consortium some of its annual fee for fiscal 2019 over the mishap.