The Department of Transportation’s Office of Pipeline Safety (OPS) said it will propose that natural gas pipelines operating in high-consequence areas be initially tested within 10 years of the effective date of its final rule, and re-tested once every 10 years afterward, or less if the inspection is conducted using the lesser-proven direct assessment method.

In a draft final regulatory evaluation issued on June 21, which reviewed the costs and benefits of the OPS proposal, the OPS unveiled its proposed 10-year timetable for testing and re-testing of high-consequence area gas pipes, and signaled it will “significantly increase the demand for internal pipeline inspection services” in the wake of the deadly explosion on El Paso Natural Gas in August 2000, the cause of which has been tentatively cited as internal corrosion. Half of the testing would be required to be completed within the first five years, the OPS said.

The agency proposed a few exceptions to the 10-year testing and re-testing intervals. Initial testing could be extended — to 13 years, for example — in high-consequence areas that aren’t densely populated, and re-testing could be extended to 15 years for high-consequence pipelines operating at less than 50% of the specified minimum yield strength, it said. Pipelines using the direct-assessment method of inspection, however, would be required to do initial testing within seven years, and re-testing at five-year intervals.

The proposed rule will require that gas pipeline operators identify pipeline segments that could affect high-consequence areas within nine months after the effective date of the OPS rule and, within one year to 1) prepare a written plan for initial inspection of all pipelines that could affect a high-consequence area; and 2) prepare a framework addressing each element of an integrity management plan for their pipelines.

An integrity plan would identify the inspection methods to be used (pressure testing, internal inspection, direct assessment or equivalent alternatives), risk factors to be considered in the selection of the appropriate testing methods for particular high-consequence areas, and the schedule of testing and inspection, according to the OPS.

The OPS defined high-consequence areas as those locations where there are at least 46 buildings intended for human occupancy or any buildings with four or more stories above ground within 600 feet of a pipeline. Also included are hospitals, schools or other facilities having persons who are confined or of limited mobility located within 600 feet of a pipeline, as well as nearby locations where 20 or more persons congregate at least 50 days in any 12-month period. In the case of large-diameter, high-pressure pipelines, the OPS proposes that the potential “impact zone” be extended to 1,000 feet or more.

The OPS plans to submit its proposed final rule for high-consequence gas lines to the Technical Pipeline Standards Committee, an advisory panel to the agency, for a vote on July 18. If approved, the OPS is expected to issue a draft of the final rule between late July and September, to be followed by a 60- to 90-day public comment period, said Terry Boss, senior vice president of environment and safety at the Interstate Natural Gas Association of America (INGAA).

The OPS rule “definitely looks like it’s headed in the correct direction,” he told NGI.

The proposed rule, OPS says, would reduce costs associated with gas pipeline-related deaths and serious injuries ($17.65 million a year), lower property damages arising from explosions and/or ruptures ($35.6 million a year), cut the amount of damages stemming from interrupted gas service, restore public confidence in pipeline safety, improve the ability of companies to site and construct new pipelines, and might result in higher operating pressures for pipelines.

©Copyright 2002 Intelligence Press Inc. Allrights reserved. The preceding news report may not be republishedor redistributed, in whole or in part, in any form, without priorwritten consent of Intelligence Press, Inc.