Toxicologists from Colorado State Health Department, United States Agency for Toxic Substance and Disease Registry, United States Environmental Protection Agency, Shell Oil Company, Tri-County Health, the Army's Surgeon General's Office, and Foster-Wheeler (or previously, Ebasco, the contractor for the project) identified the compounds and determined that there were no acute health effects. The odors ended with the completion of the excavation in December 1988.
Toxicologists from various organizations, including the Colorado State Health Department, the US Environmental Protection Agency, Shell Oil Company, Tri-County Health, the Army's Surgeon General's Office, and Foster-Wheeler (formerly Ebasco), identified the compounds present at the site and concluded that there were no immediate health risks. The odors ceased after the excavation was finished in December 1988.