Emergency cleanup operations following an oil spill in Michigan wrapped up last week, but some are still voicing concerns about the adequacy of the nation’s pipeline regulators—an issue that, unlike the regulation of offshore drilling before the Gulf disaster, has largely escaped national attention.

The Washington Independent notes that the Pipeline and Hazardous Materials Safety Administration, which regulates 2.3 million miles of oil and natural gas pipelines, has adopted “all or parts of at least 29 standards written by the oil and gas industry.” Specifically, the rules were written by two trade groups—the American Petroleum Institute and the American Gas Association. And perhaps more troubling is the lack of transparency about those standards.

From the Independent:

The industry standards touch on a number of issues key to ensuring pipeline safety, including pipeline welding, monitoring for liquid pipelines, evaluating the strength of corroded pipelines and testing pipeline pressure.

But even though these standards have been adopted as federal regulations, they continue to be the property of the oil and gas industry. As a result, public access to these standards is severely restricted. If a member of the public wants to see one of the standards, they must travel to the PHMSA headquarters in Washington or purchase the standard from API or AGA. Industry groups see the standards as proprietary information and therefore will not allow PHMSA to publish them on its web site.

The pipeline regulatory agency is plagued with some of the same problems faced by the agency formerly known as the Minerals Management Service—now the Bureau of Ocean Energy—which oversees offshore drilling.

Inspectors are lacking. (By the Independent’s count, the agency has 94 pipeline inspectors; by the Houston Chronicle’s count, it has 135.) The agency’s head, prior to her appointment as administrator of the agency, worked for Enbridge Energy Partners, the same Canadian pipeline company responsible for the Michigan spill.

But unlike its offshore drilling counterparts, it seems that by law, the Pipeline and Hazardous Materials Safety Administration also has a more limited mandate. Here’s the Independent:

Federal law mandates that PHMSA require only seven percent of the country’s natural gas pipelines and just 44 percent of the country’s liquid pipelines to be inspected.

A 2002 law mandates the inspection of pipes in “high consequence areas” — regions near natural resources like rivers, or populated areas like towns or cities. But because only portions of pipeline in the high consequence areas must undergo safety inspections, companies are under no federal regulatory obligation to adequately or consistently inspect thousands of miles of pipeline outside of those areas.

The agency told the Independent that “every U.S. government technical regulatory agency” uses standards written by other organizations, and that it encourages the rule-writers to “provide better access to standards they have authored." The American Petroleum Institute said the standards it writes are “an appropriate set of guidelines for the industry to follow,” and defended regulators for adopting them.