A wide array of state officials and environmentalists reacted with alarm following the admission today by Enbridge Inc. that the protective coating on its 64-year-old Mackinac Straits oil pipeline is gone in some places and human error by the company is likely at fault.

State Department of Natural Resources Director Keith Creagh bluntly stated that the revelation “raises concerns about the actions Enbridge is taking to protect the waters of the Great Lakes.”

The news prompted apprehension from Gov. Rick Snyder, Attorney General Bill Schuette, the Michigan Agency for Energy, the Departments of Environmental Quality and Natural Resources, and the Michigan State Police. The Canadian company’s Line 5 has been the subject of considerable anxiety in the Snyder administration and in the Legislature due to its potential for creating a catastrophic oil spill in the Great Lakes.

“Protection of Michigan’s natural resources is of utmost importance, and I am greatly concerned by the new information regarding Line 5,” Snyder said in a statement. “I have directed our departments to accelerate an aggressive review of Enbridge operations and maintenance procedures throughout the state.”

State officials are demanding an immediate investigation and repairs of the underwater line in key areas where the enamel coating is missing or at risk of deteriorating. Without the coating, the bare metal of the dual pipeline known as Line 5 is exposed and susceptible to corrosion.

Enbridge admitted today that two, possibly three, sections of the pipeline are missing the protective coating in areas where support anchors for the pipes were previously upgraded by the company.

“Human error was a major factor in Enbridge’s (2010) spill into the Kalamazoo River. These coating gaps point to other areas where human error, not the environment, are creating problems,” said Valerie Brader, executive director of the Michigan Agency for Energy. Heidi Grether, director of the Department of Environmental Quality, added that it was “completely unacceptable” that the coating apparently was damaged during the anchoring process and not immediately reported by the company.

Built in 1953, Line 5 is a 645-mile pipeline that runs from Superior, Wisconsin, to Sarnia, Canada and transports up to 540,000 barrels a day of light crude oil and natural gas liquids.

Schuette said that once inspections and repairs are completed, “We need to focus on a timeline to close Line 5, with a defined plan to ensure that Michigan residents in the U.P. have reliable access to propane, and protect our lakes with sound science and modern regulatory policy.”

That stance nearly matches the demand by the environmental group For Love of Water (FLOW), which said in a statement that the coating problems “add to the long list of unacceptable risks” that should cause the state to quickly shut down Line 5.

The coatings issue surfaced just two days after FLOW raised allegations that Enbridge or its associates may be manipulating the state’s ongoing review process of the pipeline. The Michigan Pipeline Safety Advisory Board (PSAB) is seeking public comments on what actions the state should take regarding Line 5 and the claim is that several pro-Enbridge comments submitted are fake. A Michigan woman recently came forward to say that comments attributed to her on the PSAB website were fraudulent, and FLOW asserts that “a significant number of other comments” were nearly identical. The environmental group and the Straits Area Concerned Citizens for Peace, Justice and the Environment are calling on Schuette to investigate the matter.