HOUSTON – The company whose drilling triggered the Gulf of Mexico oil spill also owns a rig that operated with incomplete and inaccurate engineering documents, which one official warned could “lead to catastrophic operator error,” records and interviews show.

In February, two months before the Deepwater Horizon spill, 19 members of Congress called on the agency that oversees offshore oil drilling to investigate a whistle-blower’s complaints about the BP-owned Atlantis, which is stationed more than 150 miles south of New Orleans.

The Associated Press has learned that an independent firm hired by BP substantiated the complaints in 2009 and found that the petroleum giant was violating its own policies by not having completed engineering documents on board the Atlantis when it began operating in 2007.

‘SLOPPINESS … LEADS TO DISASTERS’

Stanley Sporkin, a former federal judge whose Washington, D.C., firm served as BP’s ombudsman, said that the allegation “was substantiated, and that’s it.” The firm was hired by BP in 2006 to act as an independent office to receive and investigate employee complaints.

Engineering documents — covering everything from safety shutdown systems to blowout preventers — are meant to be roadmaps for safely starting and halting production on the huge offshore platform.

Running a rig with flawed and missing documentation is like cooking a dinner without a complete recipe, said University of California, Berkeley engineering professor Robert Bea, an oil pipeline expert who has reviewed the whistle-blower allegations and studied the Gulf blowout.

“This kind of sloppiness is what leads to disasters — the sloppiness on the industry side and on the government side,” he said.

BP and the Minerals and Management Service, which regulates oil drilling, did not respond to calls from the AP seeking comment on the whistle-blower allegations. But in January, an attorney for BP wrote a letter to Congress saying the company is compliant with all federal requirements and the Atlantis has been operating so safely that it received an MMS award.

“BP has reviewed the allegations and found them to be unsubstantiated,” said Karen K. Westall, managing attorney for BP.

The MMS is expected to complete its probe later this month.

Last month, the Deepwater Horizon exploded and sank 5,000 feet to the ocean floor. Since then at least 210,000 gallons of oil a day have been leaking into the Gulf, endangering wildlife, shutting down large areas to commercial fishing and threatening coastal tourism.

Government officials and critics of the oil industry say the alleged problems with the Atlantis are further evidence of systemic safety problems and lax federal regulation of offshore drilling.

“I think it’s a legitimate area of concern to ask serious questions about any rig that bears any similarity whatsoever to the Deepwater Horizon,” said Richard Charter, a senior policy adviser with Defenders of Wildlife. “If we’ve got another Deepwater Horizon waiting to happen, we’d better know about it soon.”

CONCERNS ABOUT BP

BP operates and holds 56 percent ownership in the Atlantis. It leased the Deepwater Horizon from Transocean Ltd.

The Atlantis subcontractor who lodged the complaint, Kenneth Abbott, was laid off in February 2009 and said in a written statement a few months later that he feels it was partly in retaliation, which the company denied.

When reached by the AP, Abbott said, “I had complained about BP’s problem,” but he declined to elaborate.

In a statement read during an Oct. 8, 2009, conference call, he said he has 20 years experience as a project control supervisor on various engineering projects.

“I have never been against offshore production because I believe it can be done safely but I am very concerned that BP is acting unsafely and that it may lead to a disastrous spill in the Gulf ,” he said, according to a copy of the statement.

Sporkin, who heads the ombudsman office hired by BP, said his office found in August 2009 that BP’s execution plan for the Atlantis called for all documents to be finalized and onboard before production started.

“That did not happen,” he said.

Last month, his deputy, Billie Pirner Garde, indicated in an e-mail to Abbott that BP had long known there was a document problem aboard the Atlantis.

“It was of concern to others who raised the concern before you worked there, while you were there and after you left,” she wrote.

BP production member Barry C. Duff said in an August 2008 e-mail to two colleagues that “hundreds if not thousands” of subsea documents had not been finalized, and he warned that having the wrong documents on board the Atlantis “could lead to catastrophic operator errors.”

Abbott provided e-mails, a BP database and other documents to the Washington environmental group Food & Water Watch.

DOCUMENTATION SEEMS INCOMPLETE

Members of Congress were provided the documents and a report by Mike Sawyer, a safety engineering consultant who previously aided the plaintiffs in a suit aginst BP after the 2005 explosion at its Texas City, Texas, refinery that killed 15 workers.

Sawyer reviewed a database detailing the status of thousands of Atlantis safety-related engineering documents provided by Abbott. He concluded in May 2009 that most were incomplete, introducing “substantial risk of large-scale damage to the deep water Gulf of Mexico environment and harm to workers.”

Sporkin said BP recently told his office it had fixed the problem, yet provided no written documentation.

Kenneth Arnold, a consultant to the offshore oil and gas industry for safety and project management, read the whistleblower’s allegations.

Without knowing which documents were incomplete, Arnold said it would be difficult to draw any conclusions as to how much of a threat the omissions might be. When his company worked on BP projects, Arnold said they were sticklers.

“They require more engineering and man hours than I think might be necessary,” said Arnold, who recently retired after 45 years in the industry. “If I had a complaint about BP, it is they were too detailed. People are piling on.”