State oil and gas regulators have started an enforcement action against Chevron Corp. for the massive, five-day Bishop well blowout in rural Weld County that spewed 25,000 barrels of water, fluids, sand and oil into the air in April.
The Colorado Energy and Carbon Management Commission staff on Thursday issued a notice of alleged violation to Chevron’s subsidiary Noble Energy for violating six of the state’s oil and gas rules.
“Our job is to hold operators accountable for noncompliance with our rules, and our team’s thorough investigation determined that the incident violated our rules,” ECMC director Julie Murphy said in a statement.
Noble has 28 days to respond, with the possibility of negotiations, before the case is adjudicated by the full commission.
Chevron said in a statement that it is reviewing the notice of alleged violation.
Greg Deranleau, ECMC deputy director of operations, told the commission at a hearing Thursday that in addition to the enforcement action his staff is closely monitoring Chevron’s remediation efforts.
“How likely is it that this could happen again?” ECMC Chairman Jeff Robbins asked.
Deranleau said that in his 15 years with the commission he could recall just one incident of a well blowout, which was not as serious as the Chevron Bishop well incident. “There have been 10,000 wells since that last well blowout … so it’s extremely rare.”
The Bishop well blowout near Galeton started on the evening of April 6 and wasn’t contained until the afternoon of April 10.
During those five days the well unleashed a soaring geyser composed of 20,000 barrels of produced water, sand and salts and 5,000 barrels of oil and condensates, according to Chevron.
Error before production began blamed for the blowout
In the accident report the oil company filed with the ECMC, it said the problem was an improperly installed production tree — an assembly of valves that sits atop the well to control the flow of oil and gas — as well as a poorly installed barrier suspended from the production tree that is designed to prevent the flow of liquids.
When a well is being completed it is capped with a blowout prevention device known as a BOP stack. When the well, which is under pressure, is ready for production the BOP stack is replaced with a production tree.
A barrier — a tube hanger — to control the pressure is put into place as the BOP stack is replaced. In the case of the Bishop well as the production tree was being put in place it released the tube hanger.
Fourteen households were evacuated and the Galeton Elementary School was temporarily closed. Area residents said there was a fine mist or droplets in the air.
Researchers at Colorado State University measured air emissions during the incident and found dangerous levels of toxic chemicals as far as 2 miles away.
Chevron has at the direction of local, state and federal authorities collected about 3,000 air quality measures and the Colorado Department of Public Health and Environment mobile air laboratory — a van with air monitoring equipment — also did tests in the area.
“Since the incident occurred, Chevron has maintained robust air monitoring. At no point in time did we observe levels of air pollutants that pose a threat to human health based on EPA standards,” the company said in a statement.
Soil and water samples, both surface water and groundwater, from the area have been collected and air monitoring will continue in the area.
The cleanup plan covers an area with a 1.5-mile radius from the well site, which is equal to a 7-square mile area, making it a major remediation project, Kyle Waggoner, the ECMC eastern environmental supervisor told the commission.
“How do you eat an elephant?” Waggoner asked. “One bit at a time.” The area has been divided into 300 individual parcels each with its own plan.
Homes have been steam-cleaned, barns repainted and so far 25,272 cubic yards of solids have been removed from the well site. Many of the parcels will be completed by the end of the year, Waggoner said.
“Remediation for the Bishop incident is a multistep, multifaceted process,” according to the ECMC. “The operator, Chevron, is responsible for all clean up activities.”
The ECMC said the cleanup work will be “regulated and enforced” by the agency, with the complete remediation by the spring of 2030.
In its notice of alleged violation, the ECMC staff said Chevron has violated rules governing well control, general safety requirements, oil and gas facilities, pollution and venting and flaring.
“We understand that rebuilding trust takes time and sustained effort,” Chevron said in a statement. “We remain committed to open, ongoing dialogue and to supporting the residents of Galeton as we move forward.”