PHMSA has issued an Advisory Bulletin to alert hazardous liquid and gas transmission pipeline operators of the impacts associated with flow reversals, product changes, and conversions to service.  The Advisory, issued in conjunction with newly-published Agency Guidance on these issues, recommends that operators consult existing conversion of service requirements for flow reversals and product changes and undertake additional actions in order to ensure integrity and safety.

While acknowledging in the associated Guidance that the Agency’s recommended practices are not required, PHMSA nevertheless makes a number of suggestions, including that operators consider pressure testing the entire pipeline prior to flow reversals on gas and liquid pipelines and prior to significant product changes on liquid lines.  PHMSA also recommends that operators consider taking the following steps prior to reversing flow, product changes, and conversion of service:

  • Performance of ILI and hydrostatic pressure with a spike test, “especially if historical records have indications of previous in-service or hydrostatic pressure test failures, selective seam corrosion, stress corrosion cracking, other cracking threats, or other systemic concerns;”
  • Validation of material and strength test records, and preparation of plan to obtain any missing material documentation (and if mechanical and/or chemical properties are missing, require destructive tests to confirm material properties of the pipeline);
  • Review of the adequacy of sectionalizing valves and leak detection capability;
  • Enhancement of communications with stakeholders concerning changes; and
  • Submittal of a comprehensive written plan (in reliance on the Guidance) to the appropriate PHMSA regional office for review.

PHMSA identifies certain circumstances in which the Agency believes that it may not be advisable to perform flow reversals, product changes or conversions to service, however, including:  grandfathered pipelines; low-frequency ERW pipe, lap welded, unknown seam types and pipe with seam factors less than 1.0; pipelines with a history of failure and leaks related to stress corrosion cracking,  corrosion, or manufacturing defects; pipelines operating above Part 192 design factors; or, where the change involves a product change from unrefined products to highly volatile liquids.

The actions noted above are indeed advisory, but the Agency also notes several existing regulatory requirements that may be triggered by flow reversals, product changes and conversion to service projects, including:  (1) pre-construction notification provisions of 49 C.F.R. Parts 192 and 195; (2) integrity management notifications for changes on gas systems that “substantially affect” IMP implementation, among other things; and (3) other associated O&M or IMP regulations.  As a result of these requirements, the Advisory cautions that operators should be prepared to demonstrate how they have addressed impacts to “O&M, emergency plans, control room management, operator qualification training, emergency responder training, public awareness, spill response, maps and records, and IMP programs and plans.”

Despite the fact that the recommendations are not required by law, as acknowledged by the Agency, the Advisory suggests that operators should develop and document technical justifications for their chosen course of action, particularly if they depart from the Guidance.  As operators consider making system changes to accommodate shifts in the market and demand for transportation services, the Agency will likely expect to see that they have addressed these recommendations.