Heavy metals are turning up in wildlife of a unit of the National Park System that's so far removed from most Americans that it might as well be on the other side of the world. But that shouldn't be cause for ignoring the report.
The study on birds and small mammals at Cape Krusenstern National Monument was prepared by the U.S. Geological Survey in cooperation with the National Park Service. The two agencies issued the report, Assessment of Metals Exposure and Sub-Lethal Effects in Voles and Small Birds Captured Near the DeLong Mountain Regional Transportation System Road, Cape Krusenstern National Monument, Alaska, 2006, earlier this week.
For the study, biologists captured six voles and a dozen small birds during the summer of 2006 near the DeLong Mountain Regional Transportation System haul road that leads through Cape Krusenstern on its way to the Red Dog Mine. Similar numbers of animals were captured from a comparison site at the southern end of the monument.
Analysis of biological samples found "no clear evidence of serious sub-lethal biological effects such as lesions in internal organs or DNA damage in blood in any of the animals," the Park Service said. "Though blood and liver lead concentrations were elevated in animals captured near the haul road, they were generally less than concentrations associated with serious biological effects reported from other studies."
The biologists analyzed the organs for deformities and analyzed liver and blood samples for aluminum, barium, cadmium, lead, and zinc concentrations. Voles and small birds captured from near the haul road had about 20 times greater blood and liver lead concentrations and about three times greater cadmium concentrations when compared to those from the reference site, according to an NPS release.
Barium and zinc tissue concentrations of animals collected from different sites were not remarkably different, and aluminum concentrations were below the reporting limits in most samples, it added.
While the study indicates that voles and small birds living near the haul road are not suffering serious biological effects as a result of metals exposure, the biologists are recommending that continued monitoring of lead and other metals be performed because biological effects thresholds might be approached if exposure levels were to increase.
According to the Park Service, the Red Dog Mine is one of the world’s largest producers of lead and zinc concentrates. It lies about 30 miles northeast of the boundary of the national monument, and has been in operation since 1989.
The powdered ore is moved about 55 miles by truck to the coast, including about 20 road miles within the monument. Over the years, trucks have released quantities of finely powdered ore concentrate along the road. Beginning in 1999, NPS researchers sampled moss to document patterns of airborne heavy metal deposition on public lands and found elevated concentrations of cadmium and lead. This vole and bird study is among the follow-up work stemming from those earlier studies.
The report comes a year after National Parks Conservation Association officials came out in opposition to a proposed expansion of the Red Dog Mine. It was in January 2008 when Joan Frankevich, the group's program manager for Alaska, voiced concerns over the mine.
Cape Krusenstern National Monument was created in 1978, 11 years before the Red Dog Mine opened, to protect a series of archaeological sites depicting Alaska’s rich human history—including every known cultural period in arctic Alaska. Additionally, the monument was established to protect wildlife habitat and the viability of subsistence resources. In fact, Inupiat people today practice a subsistence lifestyle within the monument, including berry picking, caribou hunting, and salmon fishing. Yet, its establishment as a monument hasn’t afforded Cape Krusenstern adequate protection.
In 2004, national park scientists found astonishingly high levels of cadmium, lead, and zinc in moss growing several miles on either side of the mining haul road, which runs through Cape Krusenstern National Monument. The source of this contamination is “fugitive dust” – dust blown from trucks traveling 19 miles along the road between Red Dog Mine and the port on the Chukchi Sea.
The toxicity of at least two of the heavy metals found in the monument—lead and cadmium—is significant. The harmful effects of lead on humans in particular are well known, leading to its removal from water pipes, gasoline, and paint. Lead can affect almost every organ in the body and cause irreversible brain damage. Children and developing fetuses are especially vulnerable to even minute amounts of lead.
According to the Park Service, Teck Cominco, which operates the mine, has taken several steps over the years to reduce the amount of material released during mining operations and transportation. The results of this USGS research are consistent with findings of the 2007 DMTS Fugitive Dust Risk Assessment that was conducted by Teck to evaluate and manage potential environmental issues related to fugitive dust releases.
While Ms. Frankevich was glad to see the latest sampling data, she was concerned about the size of the sample.
"It's reassuring and lends credence to both this report and Teck's risk assessment that the results are similar, although it is disappointing that the sample size for this study is so small. However the fact that the results are sub-lethal doesn't mean there are no effects or no problems at all," she says. "I wonder what effect this will have on the offspring of the voles and birds? If a human had lead levels in their blood and liver 20 times greater than normal that would be cause for great concern.
"Continued monitoring is warranted. Most important is that Teck Cominco continues with their efforts to contain fugitive dust and eliminate heavy metal contamination of Cape Krusenstern and the surrounding area," she adds. "NPCA strongly advocates construction of a slurry pipeline or year-round truck washes as evaluated in the recent SEIS (supplemental environmental impact statement).