Colorado regulators have published draft rules for oil and natural gas flowlines that would no longer exempt operators from pressure testing and monitoring low-pressure pipelines, as is currently required for larger diameter systems.

The draft rules are intended to strengthen oversight specifically for flowlines that carry oil, gas and wastewater from wells to tanks and other gathering equipment. The Colorado Oil and Gas Conservation Commission (COGCC), which oversees the industry and issued the draft rules, also would be required to track and alert local governments when the flowlines are abandoned.

However, a rule pushed by neighborhood groups to require statewide pipeline mapping is not in the draft, as requested by the energy industry and Gov. John Hickenlooper.

The proposed rulemaking follows an explosion in Firestone last April that leveled a home, killing two men and critically injuring the wife of one man. The explosion was traced to a severed, abandoned gas flowline from an Anadarko Petroleum Corp. well that was about 170 feet from the home.

Investigators determined fugitive gas penetrated the ground near the home’s foundation and entered the French drain, where it found its way through the sump pump and inside the home. The mix of gas and air then found an ignition source and exploded on April 17.

Hickenlooper ordered a statewide review of oil and gas operations following the preliminary investigation, and as regulators moved to determine whether other flowlines also had issues, producers voluntarily began testing systems across the state.

Anadarko, the state’s largest producer, shut in more than 3,000 wells at one point and other operators followed suit.

Following a three-month review, Hickenlooper in August called for a seven-point rules overhaul, to include more stringent flowline regulations, steps to address orphan wells and enhanced methane leak detection.

The 14-page draft issued by COGCC requires operators to purge drain lines when they are permanently taken out of service. The proposed rules would require lines to be disconnected and sealed at both ends, and any above-ground portion would have to be removed. Operators would have the option to remove the line. Lines remaining in service must be pressure-tested every year or be subject to a monitoring program.

After the draft rules were issued, Colorado Oil and Gas Association President Dan Haley said the industry group “remains committed to participating in the discussion. We hope our local government partners also contribute to the dialogue, as robust regulatory oversight of the oil and gas industry is most appropriate at the state level.

“We hope this rulemaking clarifies the processes around flowline integrity, while accounting for the diversity of our members’ operations across the state of Colorado.”

A coalition of neighborhood groups formed earlier this year, the League of Oil and Gas Impacted Coloradans, is pushing for a more stringent package of rules.

“If the governor really wanted to protect public health and safety, we need to broaden the scope of this rulemaking or we need to put together additional rulemaking,” said executive director Sara Loflin.

The coalition has pushed for a map of oil and gas pipelines accessible to the public. However, Gov. John Hickenlooper and industry have said mapping pipelines could make them vulnerable, to, for example, anyone trying to siphon off supply. A proposal to create pipeline maps failed to make it out of the state legislature earlier this year.

Boulder County officials have asked the COGCC to go further in its rulemaking. Chief planner Kimberly Sanchez and Kate Burke, assistant county attorney, sent a letter to the commission urging a map of flowlines be maintained. Mapping is “glaringly absent from the proposed scope” of the rules, they wrote.

Public hearings on the proposed rules package are scheduled for Dec. 11-12 at COGCC headquarters in Denver. Under the tentative timeline, COGCC expects to have a rulemaking in place sometime in 2018.