An appellate court's decision disqualifying the state's legal team in its feud with 3M Co. over alleged damages from PFCs in the east-metro area will be reviewed by the ­Minnesota Supreme Court.

The state's high court granted the request from the state attorney general's office and the Washington, D.C.-based Covington & Burling law firm.

In its July 1 decision, the Court of Appeals upheld the disqualification of Covington & Burling for violating professional rules of conduct in failing to properly notify 3M that it was representing the state in a lawsuit over perfluorochemicals — PFCs — that were legally dumped in Washington County over several decades.

Covington & Burling previously had represented 3M on PFC-related matters before taking the state's case in 2010 on the opposing legal side, creating a conflict of interest, the appellate court had ruled.

In a separate case, 3M also is seeking unspecified monetary damages from Covington in Ramsey County District Court for switching sides, which in legal terms is breach of fiduciary duty and breach of ­contract.

In a ruling on that case this week, Judge Margaret Marrinan ordered that — given 3M's extraordinary damage claims against one of the nation's premier law firms — Covington must turn over all electronic and paper documents involving its relationship with the company going back more than two decades. A special master has been named to oversee the turning over of that ­information.

The ruling is significant because Covington has claimed in arguing against its disqualification that information it holds about PFCs gathered when 3M was its client is not "substantially related" to the issues in the case it represents on behalf of the state.

In the Ramsey County case, Covington was seeking to restrict 3M's access to the law firm's legal intelligence about PFCs; the judge ruled, though, that 3M was entitled to all of that information. "Common sense and fair play support an order requiring that all this information … be returned to 3M," Marrinan wrote.

The law firm took the state's case at no charge. Under Covington's deal with the state, aside from expenses like travel and meals, the firm at the top end was to collect 15 percent of any pretrial settlement with 3M exceeding $150 million, and 20 percent of settlement amounts more than $150 million after the trial has started, documents show. The percentage collected by the firm was to increase as the potential settlement amount declined.

Attorney General Lori Swanson filed the lawsuit against 3M in December 2010, seeking to recover alleged and future damages to the environment from PFCs. The family of chemical compounds was developed by 3M around 1950 for use in an array of consumer products until the company stopped producing and using them in 2002, but other firms continue to do so. They're still found in fast-food wrappers, and in products treated with Teflon, Stainmaster and Gore-Tex.

3M has said that PFCs, which are so pervasive that the most common types are found in more than 98 percent of the U.S. population, cause no harm to people. The company also has spent an estimated $100 million in cleanup efforts over the past several years at sites where the PFCs had been legally dumped at sites in Woodbury, Cottage Grove, Lake Elmo and Oakdale.

Lake Elmo had joined the state in its lawsuit, but opted to withdraw as a plaintiff last month.

Jim Anderson • 651-925-5039