DOT PUBLISHES GULF PIPELINE INSPECTION RULE

The Transportation Department has issued a rule requiring inspection of all shallow water pipelines in the Gulf of Mexico.

The rule, which takes effect Jan. 6 and was drawn up by DOT's research and special programs administration (RSPA), was published in the Dec. 5 Federal Register. Congress passed a law a year ago requiring the inspections, a reaction to accidents in 1987 and 1989 in which fishing vessels struck pipelines on the seabed in shallow waters.

RULE DETAILS

The rulemaking requires pipeline operators to inspect all their natural gas and hazardous liquids pipelines in the Gulf of Mexico and its inlets by May 16, 1992, and report to DOT if any sections are exposed or buried less than 1 ft below the seabed.

The requirement applies to pipelines between the high water mark and the point where the seabed is under 15 ft of water as measured from mean low water. The rule applies to inlets, but not coastal rivers, tidal marshes, lakes, and canals. The rule exempts hazardous liquids gathering lines-but not natural gas-of 4 in. or less, and RSPA can exempt any line inspected since Oct. 3, 1989, if certain criteria are met.

If an operating company discovers a pipeline is exposed or a hazard to navigation, it is required to mark the location with a marine buoy or marker and notify DOT. Those lines must be reburied within 6 months.

COSTS DISPUTED

RSPA estimated the inspection requirements will apply to less than 1,000 miles of offshore pipeline and will cost operators $8.7 million but would have benefits estimated at $17.6 million.

In its comments on the rule, Chevron disagreed. It said RSPA's estimate of $8,000/mile for inspections is too low by $4,000 and the total cost could be $50-100 million.

RSPA will issue another rule by May 16, 1993, also required by law, establishing requirements for periodic inspections of offshore lines. That rule may answer concerns Louisiana's Office of Conservation has raised about the inspection and possible reburial of 4,000 miles of abandoned pipelines off that state.

DOT declined industry suggestions that it exempt pipelines in less than 3 ft of water from the rulemaking.

OPERATORS' CONCESSIONS

But it said it would grant operators extensions if they were making progress, but still could not complete their pipeline inspections by the May 16, 1992, deadline.

If operators could not make repairs before winter, RSPA said it would allow them to defer repairs until the following summer.

And in another concession to operators, RSPA acknowledged that although the standard calls for burying pipe 36 in. below the seabed "it is technologically impractical to expect that the initial 36 in. of burial be continuously maintained in light of the shifting silty seabed. Requiring that the top of the pipeline be at least 12 in. below the seabed provides adequate protection while recognizing the unstable offshore environment in the Gulf of Mexico."

In their comments on the rule, pipeline companies urged the Coast Guard to halt fishing vessels' prevailing practice of operating in waters of marginal depth.