A gas line inside the home was intentionally tampered with, leaking gas for up to two hours before it ignited, leveling the structure at 13072 Monroe Drive and killing a man inside on June 19.
Thornton Police Chief Randy Nelson led a community meeting Wednesday, July 16, to update the neighbors of that home on the investigation into the cause, the cleanup process and to reduce concerns about asbestos exposure.
Investigators discovered a flexible gas line was disconnected and the valve on the main gas line was found open, Nelson told a crowd of more than 100 people gathered at Stargate Charter School.
It is not clear who intentionally tampered with the gas line or why. Officials would not release any more details at this point in the investigation, which Nelson said was in the final stages.
The cause of death for 59-year-old Gary Lee Pine was pending toxicology test results, the chief said.
Pine co-owned the home and lived in the basement. He lived with two roommates who were not at home during the explosion.
The blast leveled the home and damaged five neighboring homes, which are now uninhabitable.
Nelson explained that at about 12 hours into the investigation, crews started wearing hazardous material gear because of asbestos concerns. The home was built in the 1970s and had asbestos inside its popcorn ceilings.
“What you saw was an overabundance of caution,” he said. “We really did not know at that time what we were dealing with.”
Mike Van Dyke with the Colorado Department of Public Health and Environment told the neighbors in his professional opinion their risk of exposure to asbestos was extremely low.
He said while there is no way of knowing how much they were exposed to, the asbestos was limited to the ceiling and that the drywall pieces were found in large chunks.
“Much of the drywall was recovered intact still, as long as asbestos material is intact, there's no health concern,” he said.
Van Dyke added that for the pieces that may have been tiny and airborne, the rain and wind minimized exposure to those.
The debris went about a two-block radius and a lot of debris remains on the property a month later.
Deputy City Manager Jeff Coder addressed the cleanup concerns, saying that the co-owner of the home has been in contact with his insurance agent. He said it was the city's intention to make sure the homeowner gets the site cleaned up in a timely manner. If the city has to intercede, it could take up to six months to go through the legal channels, get the proper permits for asbestos abatement and to remove the debris, he said.
The city has set up a specific page on its website for all information involving the Monroe Drive incident at www.cityofthornton.net/monroedriveincident.
Residents with questions or concerns are asked to email the city at firstname.lastname@example.org.