Anadarko Petroleum Corp., the state’s largest oil and gas producer, plans to shut down 3,000 vertical wells in northeastern Colorado after a fatal home explosion in Firestone near one of its wells.

State regulators announced they are investigating the cause of the April 17 explosion that killed two men in a recently built home located within 170 feet of a well that was drilled in 1993 and later acquired by Anadarko.

Frederick-Firestone Fire Protection District Chief Theodore Poszywak said his department also will continue to gather and analyze evidence to determine the cause of the explosion.

“While the well in the vicinity is one aspect of the investigation, this is a complex investigation and the origin and cause of the fire have not been determined,” Poszywak said.

He added that “there is no threat to surrounding homes” and said fire investigators have been in contact with surrounding residents.

Dennis Herrera, Special to The Denver Post A home explosion in Firestone Monday, April 17, 2017 killed two and sent two people to the hospital.

John Leyba, The Denver Post A couple watch the house next door to them get extinguished by Frederick-Firestone FD after a report of a house explosion on Twilight Ave on April 17, 2017 in Firestone. There was some damage to their home during the incident. There was a report of on person taken to the hospital.

Dennis Herrera, Special to The Denver Post A home explosion in Firestone Monday, April 17, 2017 killed two and sent two people to the hospital.



Dennis Herrera, Special to The Denver Post A home explosion in Firestone Monday, April 17, 2017 killed two and sent two people to the hospital.

Dennis Herrera, Special to The Denver Post A home explosion in Firestone on April 17, 2017 killed two men. On Monday, the COGCC levied an $18.25 million on Kerr McGee, a subsidiary of Occidental Petroleum, for its role in the incident.

John Leyba, The Denver Post Frederick-Firestone FD respond to a report of a house explosion on Twilight Ave on April 17, 2017 in Firestone. There was a report of on person taken to the hospital.



John Leyba, The Denver Post Flames burn inside a car as fireman takes in a fan to the house next door. Frederick-Firestone FD respond to a report of a house explosion on Twilight Ave on April 17, 2017 in Firestone. There was a report of on person taken to the hospital.

John Leyba, The Denver Post Frederick-Firestone FD extinguish whats left of a house after a report of a house explosion on Twilight Ave on April 17, 2017 in Firestone. There was a report of on person taken to the hospital.

John Leyba, The Denver Post A burned out car sits in the driveway as Frederick-Firestone FD respond to a report of a house explosion on Twilight Ave on April 17, 2017 in Firestone. There was a report of on person taken to the hospital.



John Leyba, The Denver Post Frederick-Firestone firemen extinguish some hot spots after a report of a house explosion on Twilight Ave on April 17, 2017 in Firestone. There was a report of on person taken to the hospital.

John Leyba, The Denver Post Frederick-Firestone FD extinguish whats left of a house after ar report of a house explosion on Twilight Ave on April 17, 2017 in Firestone. There was a report of on person taken to the hospital.

John Leyba, The Denver Post Frederick-Firestone FD extinguish whats left of a house after a report of a house explosion on Twilight Ave on April 17, 2017 in Firestone. There was a report of on person taken to the hospital.



John Leyba, The Denver Post Frederick-Firestone FD extinguish whats left of a house after a report of a house explosion on Twilight Ave on April 17, 2017 in Firestone. There was a report of on person taken to the hospital.

John Leyba, The Denver Post Frederick-Firestone FD extinguish whats left of a house after a report of a house explosion on Twilight Ave on April 17, 2017 in Firestone. There was a report of on person taken to the hospital.

Dennis Herrera, Special to The Denver Post A home explosion in Firestone Monday, April 17, 2017 killed two and sent two people to the hospital. Dennis Herrera/ Special to The Denver Post



Anadarko said while a lot of unknowns remain about the explosion, it would shut in all vertical wells of that same vintage out of an “abundance of caution.”

“Colorado residents must feel safe in their own homes, and I want to be clear that we are committed to understanding all that we can about this tragedy as we work with each investigating agency until causes can be determined,” Brad Holly, Anadarko’s senior vice president of U.S. Onshore Exploration and Production, said in a statement.

The wells, which produced about 13,000 barrels of oil a day, will stop operating until the company can conduct additional inspections and test associated equipment, including underground lines at each location.

The inspections should take between two and four weeks with priority given to wells closest to residential and commercial developments, the company said.

State officials issued a statement Wednesday saying that the Colorado Oil and Gas Conservation Commission has been investigating the explosion since April 18.

“It is an ongoing investigation. We are trying to assist Firestone as best as we can,” COGCC spokesman Todd Hartman said.

The commission said staffers are “evaluating additional steps to review activities in the region.”

The COGCC said it is directing environmental sampling and inspecting oil and gas wells in the area, including the Anadarko facility, located southeast of the home at 6312 Twilight Ave. Anadarko said it was assisting the investigation.

According to family members, Mark Martinez and his brother-in-law, Joey Irwin, were working on a hot-water heater in the basement of the Martinez’s home in Firestone when the house exploded. They were killed, and Martinez’s wife, Erin, was seriously injured.

Property records show the Martinez’s home was built in 2015, two years after the COGCC passed rules that required oil and gas drilling be at least 500 feet away from existing homes.