Beware!! High Pressure Pipelines

Natural gas industry representatives presented tips on safety around pipelines for Monongahela National Forest employees.

They may look innocuous on the surface, but natural gas collection and transmission lines can present dangers to the unwary. The Monongahela National Forest has numerous pipelines, plus a 50,000 acre underground gas storage field located within the boundaries. Pressures in the lines and field range from a low of 150 psi (pounds per square inch) for a distribution line to 700 or 800 psi for 20-36 inch transmission lines and more than 1,900 psi in the storage field.

Although a rare occurrence, damages to lines in the Forest have resulted in dramatic explosions and fires. To help employees better understand the precautions needed to prevent such accidents and to better identify field conditions warranting concern, two Columbia Gas Transmission employees presented several safety sessions for Monongahela employees.

They explained the multiple methods used by Columbia to check the integrity of lines, including physically walking them twice a year; aerial detection flights done 6 times a year; use of electrical currents to detect weakening; and the periodic use of 'pigs.' In gas pipeline parlance, a pig is a sophisticated monitoring tool that is sent through a section of pipeline with the flow of gas. It can detect thin spots in the line to a high degree of accuracy. Sections identified as weak can then be repaired or replaced.

In addition to explaining how Columbia monitors their lines, the two reps provided Forest employees with information on how to identify conditions in the field that would warrant notification to the company. These included sighting dead or dying vegetation in an otherwise green area around a pipeline in summer or build-ups of ice in the winter. Both could signal a slow leak.

Water bubbling or being blown into the air at a pond, creek or other wet area, or dirt being blown into the air provide another clue that something could be amiss. Hissing sounds or a gas or petroluem odor are additional items to be aware of.

While the lines are located far enough underground that a forest fire should not be a major concern, any such fires should be reported to the company so that shut down precautions could be employed if deemed necessary.

Finally the industry reps asked Forest employees to help them by reporting any signs of construction activity within the 50 foot rights-of-way maintained by the company. While it is required standard practice for contractors and others working in the vicinity of a pipeline to notify utilities of planned work, that doesn't always happen.

While it is unlikely a Forest Service employee would run into a pipeline safety issue, being aware of one's surroundings in the vicinity of such lines can mean the difference between a pleasant day in the field and a major accident.