Process Devised For Monitoring Leak Threats Using GIS

Distribution Integrity Management Rule
By James Stout, UGI Utilities, Inc., and Tony Sileo, Opvantek, Inc. | February 2009 Vol. 236 No. 2

This article shares experiences we have gained working with several customers to geo-code leak and pipe inspection reports and associate them with the pipe segment in the GIS that best matches the address location and other attributes of the report.

It also discusses GIS data-modeling considerations to facilitate data capture and presentation on the map. Finally, we suggest several on-going business process improvements to ensure threats are captured with sufficient quality and timeliness to support the DIMP regulations.

Over the past several years, Pipeline Integrity Management regulations have been implemented for pipelines transporting hazardous liquids (Title 49 CFR Part 192) and natural gas (Title 49 CFR –Subpart O). In June 2004, the DOT Inspector General, in testimony before Congress, recommended that the Office of Public Safety within DOT’s Pipeline and Hazardous Materials Safety Administration (PHMSA/OPS) require operators of natural gas distribution pipelines to implement an enhanced safety program similar to those used on hazardous liquids and natural gas transmission. As a result, a multi-phase action plan was initiated to proactively gather industry and stakeholder input about any potential safety programs.

The first phase of the action plan was completed in 2005 by four multi-stakeholder work/study groups, and resulted in a report on distribution integrity for Gas Distribution Pipelines (PHMSA, December 2005). The report concludes that it would be appropriate to modify existing pipeline safety regulations to convey the concept of a risk-based distribution integrity management process (PHMSA, December 2005). It recommends a “high-level, flexible federal regulation, in conjunction with implementation guidance, a nationwide education program, and continuing research and development.”

The report concludes that significant differences between transmission and distribution pipeline systems, as well as diversity among gas distribution pipeline operators, make it impractical to establish prescriptive requirements. Rather, operators may be required to maintain their own tailored integrity management programs that address seven key elements:

  1. Establish a Written Integrity Management Plan.
  2. Pipe Infrastructure Knowledge.
  3. Threat Identification.
  4. Risk Assessment and Prioritization.
  5. Risk Mitigation.
  6. Performance Measurement and Adjustment.
  7. Regulatory Reporting.

The second phase began in January 2006 and involved development of draft regulations by PHMSA in parallel with preparation of guidance materials and standards by industry and government organizations, including the Gas Piping Technology Committee (GPTC).

As part of the Pipeline Inspection, Protection, Enforcement, and Safety (PIPES) Act signed in December 2006, congress mandated a federal rule on distribution integrity management by the end of 2007. In a departure from the usual approach aimed at maintaining closer alignment between various stakeholders and the final regulations, the GPTC guidance materials were drafted prior to publishing the final regulatory language, and were essentially ready for initial release by fall 2007.