December 2018, Vol. 245, No. 12



Change of Class Location Draws Opposition

Citizen organizations and state regulators are opposing interstate pipeline efforts to convince federal regulators to provide an alternative to the class location system, which requires pipelines to take steps when there is population growth around a pipeline.  

The Interstate Natural Gas Association of America (INGAA) wants the Pipeline and Hazardous Materials Safety Administration (PHMSA) to, in effect, expand class location safety requirements, which it considers outdated, by allowing an integrity assessment option for managing class location changes for instances in which class locations change from Class 1 to Class 3 and Class 2 to Class 4.

PHMSA raised the possibility of either eliminating or altering class location requirements in August with an advanced notice of proposed rulemaking (ANPR). Pipelines have been pressing for changes to the class location requirements for decades because the cost of replacement in low-density is expensive and sometimes unnecessary.

Increases in population near a pipeline – that can be as few as 500 people – force a pipeline to confirm safety factors and recalculate the maximum allowable operating pressure (MAOP) of the pipeline

If the MAOP per the newly determined class location is not commensurate with the present class location, current regulations require that pipeline operators (1) reduce the pipe’s MAOP to reduce stress levels in the pipe, (2) replace it with pipe that has thicker walls or higher yield strength to yield a lower operating stress at the same MAOP, or (3) test at a higher pressure if the pipeline segment has not been tested at the higher pressure for a minimum of eight hours.

INGAA understands any action on the new ANPR awaits a final rule based on a 2016 proposal that would require interstate pipelines to expand integrity management to areas beyond high-consequence areas (HCA). The final rule, ostensibly modified by suggestions from a PHMSA advisory committee, is due to be published in March 2019. Because that final rule will expand integrity management (IM) requirements, INGAA believes that it is now time to provide the pipelines with an IM option for dealing with class location changes.

A number of citizens groups and the state pipeline safety oppose an IM option to the class location requirements. But C.J. Osman, director of Operations, Safety and Integrity at INGAA, said he hopes that as ANPR is discussed, including in the forum of the advisory committee meetings, that opponents can be convinced of the merits of the INGAA-sought option.

Pipelines can apply for special permits that allow the circumventing of class location requirements in certain situations. 

Lynda K Farrell, executive director, Pipeline Safety Coalition, a Pennsylvania group, refers to a National Transportation Safety Board (NTSB) study and a PHMSA advisory bulletin to underpin her statement that the “ANPRM is premature and that allowing a relaxation of class location strength requirements is ill-advised.”

Farrell also refers to comments from the National Association of Pipeline Safety Representatives to buttress her opposition to any changes in class location requirements. 

The NAPSR comments said: “Class locations are primarily a design safety measure. Replacing a design measure with an operation measure does not improve safety. Integrity management strategies have been critically important to pipeline safety success, but we feel that the reliability of these measures have not evolved to a level where their total dependency would be practicable. We have observed some recent accidents resulting from misapplication in managing ILI technologies, especially when managing cracks and interactive defects. There are too many accidents related to mismanagement of integrity management issues to justify eliminating class locations in lieu of integrity management.”   

Pipeline Safety Trust acknowledged the importance of upcoming IM changes in the finalization of the 2016 proposed rule and said any modifications to the class location requirements should wait until “the gas safety rule, now in the works for seven years, is complete and the integrity verification process (IVP) process for identifying and verifying operator system records is in place and shown to be working to improve operator assessments of their systems.” 

Osman agrees that some of the comments on the ANPR oppose INGAA’s position based on technical concerns. He acknowledged, “The onus is on us to prove this is the right change to make, to explain why the integrity management program offers not just equal protection but a safer alternative to the current class location method.”

NTSB Preliminary Report Points Finger at Cast Iron 

An NTSB preliminary report published Oct. 11 on the local gas pipeline explosion in Massachusetts in September is likely to spur renewed attention to the safety of cast-iron distribution lines. 

Columbia Gas of Massachusetts, a subsidiary of NiSource, is in the process of replacing the 48-mile, cast-iron and bare-steel distribution system in three communities with modern infrastructure and safety features, such as excess flow valves. The current system was installed in the early 1900s and had been partially improved with both steel and plastic pipe upgrades since the 1950s.

The explosion, caused by an over-pressurized system, damaged 131 structures Lawrence, Andover and North Andover. In addition to the one death, at least 21 people, including two firefighters, were transported to the hospital.

The safety of cast-iron pipe in gas distribution systems has been a major concern for some time. In 2012, President Obama signed the Pipeline Safety, Regulatory Certainty and Job Creation Act, requiring a survey by PHMSA of the nation’s progress in replacing cast iron gas pipelines. That provision was inspired in part by the death of five people in 2011 in a gas explosion in Allentown, Pa., where cast iron pipe was the culprit.

For the most part, the safety of distribution lines is a matter for state officials, not PHMSA, which issued a 2012 advisory bulletin to owners and operators urging a comprehensive review of cast-iron distribution pipelines and replacement programs, along with acceleration of pipeline repair, rehabilitation, and replacement of high-risk pipelines. 

According to statistics, PHMSA has assembled in compliance with the 2012 Pipeline Act, 20 states have completely eliminated cast-iron pipeline from distribution systems. About 97% of natural gas distribution pipelines in the U.S. were made of plastic or steel at the end of 2017. The remaining 3% is mostly iron pipe. Nationally, cast- and wrought-iron distribution main mileage has decreased by almost 38% from 2005 to 2017. The number of cast- or wrought-iron service lines has decreased by almost 77% over the same time period. P&GJ

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