Watchdog group says LANL data shows widespread plutonium migration

Apr. 25—Trace amounts of plutonium from decades of weapons work at Los Alamos National Laboratory have contaminated the Rio Grande at least as far as Cochiti Lake and could be in the regional aquifer that serves a large population of New Mexicans, a nuclear watchdog says.

"That's been long known," Nuclear Watch New Mexico Director Jay Coghlan said in a virtual briefing Thursday morning, when the organization unveiled a map of plutonium migration it said was created with LANL's own data.

"Nevertheless, it's not generally known by the New Mexican public," Coghlan said. "What is 'new news' is publicly calling that out."

Nuclear Watch used what it called the lab's publicly accessible but cumbersome environmental database, Intellus New Mexico, to map 58,100 spots where the lab collected samples between 1992 and 2023, including 17,483 labeled as plutonium "detects." The interactive map shows the date each sample was collected and the level of plutonium detected, with two "detects" cited in Cochiti Lake, dozens in the Rio Grande east of Los Alamos and thousands around the lab.

Thursday, LANL and U.S. Department of Energy leaders disputed in emails plutonium has been detected in surface water or groundwater off lab property.

Energy Department spokeswoman Stephanie Gallagher wrote "no groundwater or surface water samples have shown migration of plutonium contamination" off-site.

Lab spokesman Steven Horak rejected Nuclear Watch's interpretation of the Intellus data. Instead, he wrote in an email, the data "simply represent[s] where environmental sampling has been conducted."

"Based upon years of peer-reviewed sampling data, LANL disagrees with the notion there is a plutonium plume and that plutonium is migrating to the regional aquifer," Horak wrote.

"The safety of the public, the workforce and the environment is a priority for DOE and the Lab, which is why we have comprehensive sampling and monitoring programs and a dedicated legacy cleanup program that is addressing the WWII and Cold War-era legacy contamination across the Lab," he continued.

Coghlan and chemist Michael Ketterer acknowledged Nuclear Watch New Mexico cannot say with certainty plutonium has contaminated deep groundwater. That's because the lab's sampling method has been flawed, they said.

They question the lab's thresholds for plutonium detection, arguing samples could contain small amounts of the radioactive element that fall below the levels the lab reports as "detects."

Ketterer, a professor emeritus of chemistry at Northern Arizona University with extensive experience studying plutonium in the environment, collaborated with Nuclear Watch on the plutonium map pro bono, he said, adding he also has been independently scrutinizing LANL's monitoring.

The lab's methods for measuring and reporting plutonium concentrations in the environment do not follow accepted scientific practice, Ketterer wrote in a letter to the state Environment Department on Tuesday.

He said in Thursday's briefing the lab's detection limits for environmental samples are inconsistent, creating an unnecessary "gray area" obscuring "the truth of the matter: Is plutonium present [in samples] or is it not?"

The lab has the tools to detect very small levels of plutonium, he said; however, scientists' chosen methods of detecting the particles can increase the limits of detection, or the lowest concentrations of plutonium reliably detected. He wrote in his letter to the Environment Department LANL contractors have labeled plutonium as "non-detected" in many samples, despite an "extraordinarily high" level of reported plutonium activities.

"This raises the question as to whether LANL and/or its contractors and labs are actually making deliberate efforts to artificially elevate" limits of detection, he wrote.

Horak defended the lab's environmental sampling practices, which he said meet scientific standards. Samples are sent to "certified independent third-party laboratories" that use "rigorous and validated techniques." Those labs, rather than LANL or the Department of Energy, make the determination of whether plutonium is detected or not, he wrote.

"We have confidence in these results, have no overriding concerns about the data quality, and emphasize that research and data collection efforts have been done in an appropriate and scientifically valid manner," Horak wrote.

Ketterer said many samples of soil and water recorded in LANL's database raise concerns about the potential effects to public health.

The New Mexico Administrative Code sets an unenforceable guideline of 1.5 picocuries of plutonium per liter of water in the Rio Grande, and water samples from the early 2010s near the Buckman Direct Diversion — which supplies much of the water for the city and county of Santa Fe — showed concentrations above that, up to 3 picocuries per liter, Ketterer said.

By comparison, Colorado has a much lower, enforceable standard of 0.15 picocuries per liter, he noted.

Horak wrote in an email lab leaders are not concerned about plutonium contamination threatening the safety of drinking water in Northern New Mexico. Wells in Los Alamos County, Santa Fe County and the San Ildefonso Pueblo regularly test "well below [Department of Energy] screening levels for plutonium."

Horak and Coghlan agree Santa Fe's water is safe to drink.

But the extent of plutonium contamination originating from LANL "should be of great concern to Northern New Mexicans," Coghlan said.

He argued his group's plutonium migration map provides "compelling evidence of the need for a comprehensive cleanup" at the lab. The Department of Energy instead has proposed a plan to "cap and cover" 190,000 cubic yards of waste in unlined pits and trenches, at an estimated cost of $12 million.

Many local organizations and community leaders, including the Santa Fe County Commission, have opposed the plan, and the New Mexico Environment Department issued a draft order in September calling for a full cleanup — at a cost of about $800 million.

Environment Department spokesman Matthew Maez did not respond to a request for comment Thursday.

Ketterer's letter asked the agency to demand heightened transparency from LANL regarding plutonium monitoring.

"The Lab is not shy in reminding the public about hosting some of the country's brightest scientists," Ketterer wrote. "New Mexicans deserve to see some of the Lab's best scientific efforts being used to protect the public health of its neighbors and the quality of its own environment."