JEFFERSON COUNTY — Steve Keller digs some dirt out of the ground with a spade, pulls loose the rocks and roots in his gloved hands and places the soil in a shiny silver bowl. It is then packed into a lidded jar and carefully labeled.
Pretty mundane work except when you consider where it’s being done: Rocky Flats, a 6,200-acre national wildlife refuge northwest of Denver that was home to four decades of toxic nuclear weapons manufacturing workand still contains a 1,300-acre no-go zone right in the middle.
It’s the first time in 13 years that soil samples have been taken in and around Rocky Flats, a Cold War relic that has for years attracted vociferous criticism and lawsuits from those concerned that hikers and bikers could be exposed to plutonium and other industrial contaminants deposited by years of weapons production. Several metro area school groups have barred students from going to Rocky Flats on field trips.
The sampling is not limited to the two sites on the edge of the refuge where Keller, a technician with Fort Collins-based Engineering Analytics Inc., was digging Monday. Samples have also been collected inside the refuge where trails are planned and along its eastern edge, where transportation officials are hoping to build the controversial Jefferson Parkway.
In all, approximately 250 surface or subsurface samples have been gathered over the last two weeks and sent to the lab for analysis.
“It is local governments and U.S. Fish and Wildlife that are saying this kind of information is important, it’s valuable, and it speaks to community concerns,” said Dave Abelson, head of the Rocky Flats Stewardship Council. “There’s been a thorough sampling in the past and further sampling is of value.”
The last time soil sampling was done at Rocky Flats was 2006, just a year after a $7 billion cleanup of the highly polluted site was completed. Results from the current sampling efforts likely won’t be analyzed and released for several weeks.
“It’s great to have another dataset and see if there is any variability,” said Roy Laws, an environmental engineer with Jefferson County Public Health who was in the field with the two-person crew on Monday.
Engineering Analytics will specifically be measuring for plutonium, americium and uranium and seeing whether levels of the radionuclides are a hazard to human health. On Monday, it sampled at two future trailheads — one on Indiana Street and the other on State Highway 128 — where refuge officials hope to build a bridge and tunnel, respectively, to provide safe access points for cyclists and pedestrians entering or passing through the refuge.
Local communities, like Boulder, Broomfield, Arvada and Westminster, agreed to provide matching funds for a $2.9 million federal grant to build the bridge and underpass, but only if additional soil samples were taken.
Doubters of the safety of Rocky Flats National Wildlife Refuge, which opened to the public in September, wanted more assurance that the soil samples will be properly analyzed. The Rocky Mountain Peace and Justice Center, which has sued the U.S. Fish and Wildlife Service over the refuge’s opening, hired retired Northern Arizona University chemistry professor Michael Ketterer to help process the samples being collected this week.
Ketterer watched the sample collections Monday and said Engineering Analytics’ efforts were “reasonable to get a rough idea” of what is on the edge of the refuge. The firm is taking 25 samples across both sites, anywhere from 2 inches to 12 inches underground, including a pair of 20-foot-deep samples where the pedestrian bridge is planned over Indiana Street.
Daniel Brenner, Special to the Denver Post
Engineering Analytics environmental engineer Megan Carroll, left, records data while engineer technician Steve Keller collects environmental soil samples Monday, July 1, 2019 at Rocky Flats National Wildlife Refuge.
Ketterer said he will use mass spectrometry to determine the “fingerprint,” or source, of plutonium in the soil taken at both sites.
Dave Lucas, U.S. Fish and Wildlife manager of the Rocky Flats National Wildlife Refuge, said he doesn’t anticipate any of the new readings to show anything different than what was found in years before — that is, levels of contaminants that have fallen well within the parameters that health officials consider safe.
“One would assume these will be consistent to the thousands of soil samples already taken,” he said.