Lockheed Martin has publicly disclosed that a solid mass of industrial waste containing hexavalent chromium — a toxin known to cause cancer — was discovered at its Waterton Road facility last October.
The state health department confirmed that the waste was safely removed along with surrounding soil, and said the health of the public and company employees was never at risk. The department also said the waste “had no impact on surface or ground water.”
According to Matt Kramer, a spokesman for Lockheed Martin, the company discovered the buried industrial waste during routine maintenance of a parking lot at its facility at 12257 S. Wadsworth Blvd., near the Audubon Center at Chatfield State Park.
“The waste was analyzed and determined to be sodium nitrate, a kind of salt, which was likely used in manufacturing processes in a nearby building several decades ago," Kramer said. "Upon discovering the waste, we notified the Colorado Department of Public Health and Environment and took immediate action to confirm it posed no danger to the public or our employees on the site.”
The sodium nitrate waste salt had solidified into a mass that was approximately 1 to 2 feet thick, 20 feet wide and 50 feet long, according to the state health department; the mass was buried about 3 feet below asphalt near the facility's south factory loading dock.
Testing found a significant concentration of hexavalent chromium in both the waste salt and the soil around the mass after it was removed.
More than 100 times the acceptable level
Currently, the Environmental Protection Agency's recommended residential soil screening level for hexavalent chromium is 0.3 parts per million. Testing at Lockheed Martin's facility found a concentration of 37 parts per million in the waste salt itself — more than 100 times the EPA's acceptable amount. Testing after removal of the waste salt still showed a concentration of 14 parts per million in the floor of the excavation area, as well as a concentration of 2.9 parts per million in the walls around the mass after the excavation.
Jeannine Natterman, public involvement coordinator for the state health department, said Lockheed Martin notified the state of the discovery verbally and in a letter dated Nov. 4, 2015, before electing to remove the mass and all affected soil; initial discovery of the mass occurred Oct. 26, 2015.
The state health department said public disclosure of such discoveries is required only at specific milestones in the mitigation process; as a result, Lockheed Martin was under no legal obligation to publicly disclose the finding sooner.
Kramer said the company spent more than $200,000 to remove the waste and ultimately treated the area with calcium polysulfide, which is also known as lime sulfur and is regularly used to treat hexavalent chromium contamination. The mass and contaminated soil were later transported to an industrial waste facility for proper disposal.
No threat to public health, state says
While the mass itself was considered hazardous waste and contained a large concentration of hexavalent chromium, the state health department said it doesn't believe the waste posed a threat to public or worker health.
“The sodium nitrate salt was located under a parking lot, was very limited in size and was a solid, so it had no impact on surface or ground water. Because it was under a layer of asphalt, there was not potential for public or worker exposure,” Natterman said.
In large amounts, sodium nitrate meets the definition of characteristic hazardous waste for "ignitability" and requires prompt removal. Hexavalent chromium compounds are classified as genotoxic carcinogens, and repeatedly inhaling them has been scientifically shown to increase the risk of cancer. The toxin is perhaps best known for its role in the Hinkley, Calif., groundwater contamination lawsuit against Pacific Gas and Electric Co. spearheaded by legal clerk Erin Brockovich in 1993.
Public comment period open through mid-August
A public comment period regarding the cleanup actions opened June 29 and will run through Aug. 12. While the comment period is required by federal regulation, Natterman said the state will consider all feedback regarding the treatment of the waste at the facility; more specifically, if members of the public are unsatisfied with the actions taken to remove and treat the waste, the state will consider additional cleanup efforts.
Interested parties may submit written comments regarding the "Correction Action Plan Construction Completion Report"and the waste-mass removal to Colleen Brisnehan, Hazardous Materials and Waste Management Division, Colorado Department of Public Health and Environment, Mail Code HMWMD HWC B2, 4300 Cherry Creek Drive South, Denver, CO 80246-1530. Telephone: 303-692-3357 or toll free at 888-569-1831, ext. 3357; e-mail: email@example.com.
Any member of the public may request a public hearing on the report. The report is available for viewing at the Columbine Public Library or by appointment at the Colorado Department of Public Health and Environment from 8 a.m. to 5 p.m. Call Pearl Campos at 303-692-3331.
Contact reporter Sal Christ at firstname.lastname@example.org or at 303-350-1035.