The Department of Transportation’s Pipeline and Hazardous Material Safety Administration (PHMSA) has moved forward on improving and expanding the Integrity Management Program (IMP) for gas pipelines, first established in 2002 as 49 CFR Part 192 Subpart O.
The rule requires gas pipeline operators to develop an IMP for transmission pipelines that could affect high consequence areas in the event of pipeline failure. Pipeline operators must also conduct baseline assessments and continually monitor system conditions through periodic reassessments.
While the first IMP rule provided a solid framework for risk management of gas pipelines, recent pipeline failures indicate that the IMP regulation is not clear enough. As a result, PHMSA is working to expand the requirements for three of the IMP risk management criteria:
The proposed new IMP rule, called the Safety for Gas Transmission and Gas Gathering Rule, will likely include more prescriptive integrity management requirements for material documentation, MAOP verification, seam stability, leak detection, piggability, and so on, to improve operator awareness of system infrastructure.
To better identify and evaluate risks, PHMSA will also likely clarify the definition of an adequate risk model and data validation as well as the subsequent assessment and analysis and the treatment of interactive threats. As part of the review and improvement to the IMP, PHMSA has expressed support for the new Safety Management System Standard, API Standard 1173 that is being developed by the American Petroleum Institute, though support does not guarantee reference in the new IMP rule.
In addition, the new IMP rule will expand the definition of meaningful metrics and inspection protocols with emphasis on oversight and transparency. The new rule could also extend IMP requirements beyond pipelines in high consequence areas (HCA) due to recent incidents in non-HCA segments that had adverse consequences to HCAs. Jeff Wiese and Linda Gougherty of PHMSA* noted that currently the IMP rule affects approximately 7% of the 300,000 miles of regulated, on-shore, natural gas pipelines.
The proposed new rule is likely to affect a significantly larger amount of the regulated on-shore pipelines. These proposed requirements might include periodic integrity assessments and specific repair criteria to segments outside HCAs in a proposed moderate consequence area (MCA) which is defined as (ref Steve Nanny presentation at IPC 2014):
Although the title of the new rule implies that it will add criteria for managing the integrity of gas gathering lines the paper referenced does not specify what that may be nor have we seen anything else by PHMSA in writing that addresses proposed changes to gas gathering regulation.
PHMSA has stated that the Notice of Proposed Rulemaking (NPRM) for the new IMP rule is expected to be published in the federal record around the first quarter of 2015. Once the NPRM is published the public will have a year to provide comments. PHMSA will then take time to address the questions as it finalizes the rule. Once finalized, the new rule will be published in the federal register with a stated effective date. As yet, there has not been any documentation as to how long the pipeline operators will have to implement the new rule.