LANL’s seismic safety questioned; lab says improvements are being made

By Mark Oswald / Journal Staff Writer
Wednesday, December 4th, 2019 at 10:00pm

SANTA FE – An independent oversight board says that efforts to improve safety at Los Alamos National Laboratory in case of an earthquake — the lab sits on a fault — have stagnated and remain incomplete, even as the lab’s mission is ramping up for production of plutonium cores for nuclear weapons.

The Defense Nuclear Facilities Safety Board’s report says that a number of concerns “call into question the overall adequacy of the current set of safety controls to protect the public and workers.”

A LANL spokesman provided a statement saying the lab has completed many seismic upgrades and is confident that current and future improvements to its plutonium facility “will fully support the Lab’s mission needs and meet the safety requirements related to any credible seismic event.”

Studies have shown Los Alamos has a probability of a major earthquake once every 10,000 years. [This is incorrect. It should be three earthquakes in the Holocene, i.e. the last 11,650 years.] In the worst case, a devastating quake would be followed by a fire that could spread contamination.

The DNFSB, created by Congress as a safety watchdog for nuclear weapons labs, said there has been agreement for more than a decade over necessary upgrades to seismic safety systems at LANL’s plutonium facility known as PF-4.

LANL has completed several projects, the report says. But completion dates for upgrades “to fire barriers, as well as the ventilation and fire suppression systems, have slipped well beyond LANL’s initial estimates,” says the Nov. 15 report to U.S. Department of Energy. “These systems are essential to LANL’s safety control strategy for post-seismic fires.”

LANL hasn’t taken into account the impact of falling equipment on spreading doses of radioactive materials, the report states. It says about 75 percent of the gloveboxes at LANL where plutonium work takes place “either do not meet seismic criteria or have not been analyzed to demonstrate that they will not topple in a seismic event.”

Other findings in the DNFSB report include that LANL has underestimated the potential dose consequences to the public and workers of “heat source plutonium oxides” and that the lab’s assumptions about how quickly exit doors can be closed to prevent hazardous materials leaks after a quake are overly optimistic.

The statement from the LANL spokesman says the lab has in fact completed many structural upgrades at PF-4 “including shield walls, glovebox stands, column supports, and ceiling beam enhancements.”

“Ongoing full scale tests of concrete columns show actual seismic performance of these columns exceeds previous assumptions,” the statement said. “Fire suppression system upgrades include suppression piping support, upgraded fire alarm panels and a future fire alarm system replacement, and additional diesel generators to support electric fire pumps. In addition, the Laboratory has installed reliable electrical power distribution to ventilation systems.”

The statement adds that LANL “has for several years continually worked to reduce Material At Risk (MAR) throughout the PF-4 facility to further meet seismic safety requirements.”