[Docket No. PHMSA-2021-0046]
On September 7th, PHMSA’s Notice of Proposed Rulemaking (NPRM), Safety of Gas Distribution Pipelines and Other Pipeline Safety Initiatives, was published in the Federal Register. This NPRM would require gas distribution operators to update their distribution integrity management programs (DIMP), emergency response plans, operations and maintenance manuals, and other safety practices. This NPRM implements congressional mandates from the Leonel Rondon Pipeline Safety Act and an NTSB recommendation directed toward preventing catastrophic incidents resulting from over pressurization of low-pressure gas distribution systems, similar to what occurred on a gas distribution system in Merrimack Valley, MA on September 13, 2018. The 59-page rulemaking is quite extensive, and includes (among other requirements):
- Improving construction procedures designed to minimize the risk of incidents caused by system over-pressurizations.
- Updating Operator’s DIMP plans to consider and prepare for the threat of over-pressurization, specifically over-pressurization on low pressure systems.
- Requiring new regulator stations to be designed with secondary pressure relief valves and remote gas monitoring, to better prepare gas distribution systems to avoid over pressurizations, and limit damage during incidents.
- Strengthening emergency response plans for gas pipeline emergencies, including requirements for operators to contact local emergency first responders / public officials for incidents involving fire/explosion/fatality/significant interruption and keep customers and the affected public informed of what to do in the event of an emergency and post incident.
- DIMP plans to be required to assess risk of cast iron, bare steel, unprotected steel, wrought iron, and historic plastics with known issues and low-pressure distribution systems, as well as the possibility of future accidents, to better account for high-consequence but low-probability events.
- DIMP plans to consider factors that increase the likelihood of failure such as age, increase the overall risk (including factors that simultaneously increase the likelihood and consequence of failure), and limit the effectiveness of leak management programs.
- Operators to consider and take appropriate action to address the impacts of extreme weather as a threat, regardless of whether they had experienced such events in their pipelines’ history, while still recognizing regional differences.
- DIMP plans to assess risk to low-pressure gas burning equipment.
- Revise O&M manual / Emergency plans to include procedures for responding to overpressure indications.
- MOC procedure to account for significant changes to distribution system, and to ensure SME review/approval of relevant construction plans.
- Traceable/Verifiable/Complete records for gas distribution facilities “critical to ensure proper pressure controls.”
- Monitoring for overpressure by OQ-qualified person during certain construction projects.
- Assess risk of (and eliminate) common mode of failure at district regulator stations.
- Construction inspection requirement for inspections to be performed using different personnel to conduct the inspection than had performed the construction activity.
PHMSA also proposes to codify use of its State Inspection Calculation Tool, which is used to help states determine the base-level amount of time needed for inspections to maintain an adequate pipeline safety program. PHMSA proposes other pipeline safety initiatives for all part 192-regulated pipelines, including gas transmission and gathering pipelines. This includes updating emergency response plans and inspection requirements. Finally, PHMSA proposes to apply annual reporting requirements to small, liquefied petroleum gas (LPG) operators in lieu of DIMP requirements.
For a copy of the NPRM, click here.