Colorado regulators this week approved comprehensive rules addressing oil and natural gas flowlines, a response to a fatal explosion last year in a Denver area neighborhood.

The nine-member Colorado Oil and Gas Conservation Commission (COGCC) unanimously approved the updated regulations late Tuesday, which include new and amended rules. The approval followed three days of testimony from the public, local governments, homebuilders, citizen groups, trade associations and members of the energy industry on more than 20 pages of regulations.

“We believe these new rules are another important step in the aftermath of the Firestone tragedy,” said Gov. John Hickenlooper. Last summer he had proposed an overhaul in reaction to an April 2017 flowline explosion at a residence in Firestone.

A flowline from an Anadarko Petroleum Corp. well in Firestone ruptured, leveling a residence and killing two men and severely injuring one man’s wife.

“State government and local municipalities depend on the commitment that industry is doing everything to keep our communities safe,” said the governor.

The flowline rules take several steps to strengthen requirements for design, installation, maintenance, testing, tracking and abandoning flowlines. Flowlines are pipelines that most typically move fluids around specific oil and gas development locations from wells to separators to storage tanks or to larger pipelines.

The new rules include dozens of changes and improvements to flowline oversight.

COGCC approved requirements for more detailed tracking, location data and recordkeeping for flowlines that carry fluids away from a specific oil and gas location. These include lines that may travel from a well to a storage tank not co-located on the same well pad, or to a gathering line.

COGCC would be permitted to share resulting, more specific geospatial information on these flowlines with local governments through a confidentiality agreement.

Regulators also approved rules covering flowlines not in use — but not yet abandoned. They now must be locked and marked.

All of the lines not in use must continue to undergo integrity testing “under the same standards as active lines until abandonment,” under the revamped rules. Any risers associated with abandoned flowlines also must be cut below grade.

“This rule change makes permanent the post-Firestone order to eliminate above-ground risers connected to abandoned flowlines,” COGCC noted.

More detailed requirements also were approved for operators to demonstrate flowline integrity, including updated standards for integrity-testing lines, more testing options that align with newer technology and eliminating pressure testing exemptions for low pressure lines.

In addition, COGCC approved requirements for full operator participation in the Utility Notification Center of Colorado’s “one-call” program to ensure a centralized home for all data on flowline locations and access to the information through the established 811 “call-before-you-dig” system.

The new flowline rules and enhanced participation by operators in 811 include three key components of state actions outlined by Hickenlooper following a three-month review of oil and gas operations last year.

“Our work with operators last spring and summer to identify, quantify and test all flowlines near residential areas was a significant start,” said COGCC director Matt Lepore. “These rules — and additional actions ordered by the governor that are still unfolding — continue to keep our focus on this work.”

The final draft of the proposed rules and an overview of the COGCC’s basis and purpose for the rules were discussed during the public hearing. COGCC also provided all of the documents associated with the rulemaking, including formal statements from parties to the hearing.

COGCC has directed staff to empanel a stakeholder group “representing a cross-section of interests to review current and developing instrument-based technologies and methods for preventing or detecting leaks and spills from flowlines.”

Staff is to issue a final presentation of the results and associated recommendations for changes to COGCC’s policies or rules within a year.

The flowline rulemaking is the latest “in a consistent and long-running effort to strengthen the regulatory oversight of the COGCC, dating to 2008,” the commission noted.

The state has experienced a huge uptick in oil and gas development over the past decade.

In response, the COGCC under the Hickenlooper administration noted that it has crafted rules to increase distances between drilling and neighborhoods; reduce the effects of light, noise and odors; protect groundwater; and reduce air emissions in partnership with the Colorado Department of Public Health and Environment.

The commission also noted that it has implemented rules to disclose hydraulic fracturing chemicals; tighten requirements for spill reporting; increase penalties for operators violating rules; toughen requirements for operating in floodplains; and amplify the role of local governments in siting large operations near communities.

In addition, the COGCC said it had “significantly expanded inspection, engineering, reclamation, and environmental staff; increased ease of access and the volume of data available to the public; intensified collaboration with local governments; sponsored ongoing studies to increase understanding of impacts to air and water; and adopted several formal policies to address health, safety, and environmental issues brought about by new technologies…”