Baltimore City Council President Walter S. Orlinsky, who built a political career as a reformer and who unsuccessfully sought the Democratic nomination for governor in 1978, was indicted by a U.S. grand jury yesterday on charges that he accepted $11,000 in bribes to help companies obtain city sludge-hauling contracts.

The 12-count indictment issued by a grand jury in Baltimore charged Orlinsky with mail fraud, wire fraud and extortion in seeking to secure contracts for Modern-Earthline, a Philadelphia firm that offered to haul sludge to Garrett County in far western Maryland, and two other companies.

The usually talkative Orlinsky, 43, left a City Council meeting without explanation early Monday night and declined yesterday, through an aide, to comment "at this time."

Baltimore Mayor William Donald Schaefer, who frequently has been at odds with Orlinsky in matters of policy and style, said he was "stunned by the indictment and very saddened for Mr. Orlinsky's family. In all my years of knowing Mr. Orlinsky, he never did or said anything I would consider improper."

The indictment charged that Orlinsky received four payments totalling $10,000 between Dec. 15, 1980, and June 4, 1981, with the promise of more to come, from Edward J. Russell, allegedly acting as an agent for Modern-Earthline Companies.

According to the indictment, the firm, with Orlinsky's help, obtained a two-phase contract in November 1980 to take sludge from the city's Back River waste water treatment plant to Garrett County, where it would be used to reclaim abandoned strip mines by covering the surface with sludge. Under the first demonstration phase, the company received nearly $300,000, but local opposition blocked the project and no sludge was hauled.

After the firm failed to find other suitable sludge disposal sites, the city canceled its contract in January. Jerome Richter, a company lawyer, said yesterday he had not yet seen the indictment, but noted that no criminal charges had been filed against the firm, its officers or employes.

Orlinsky also was charged with receiving $1,000 from Russell on Jan. 5, allegedly to help two other firms -- Environmental Synergistics and Stewart Environmental Systems -- obtain sludge removal contracts.

In that instance, according to the indictment, neither firm was aware of or participated in the "corrupt agreement" carried out by Russell, who was by then cooperating with the FBI. Other firms later obtained the award. They also have had problems finding disposal sites.

Orlinsky learned about Modern-Earthline through Frank A. De Filippo, whom the firm hired as a public relations consultant. De Filippo, who had been press secretary to convicted former Maryland Gov. Marvin Mandel, said yesterday "I called Wally and said, 'You gotta come see this' presentation because Wally was really into waste disposal."

According to the indictment, Orlinsky was to "introduce (Modern-Earthline) to representatives of the city, would vote for the contract (and) would take other steps to advance the interests" of the firm. With Orlinsky voting in the affirmative, the contract was approved in November 1980 by the board of estimates, over which he presides.

"There's no question I was a pivotal character, if you wish," Orlinsky told The Baltimore Sun in February for a story about the grand jury probe that culminated in yesterday's indictment. The contract was awarded without competitive bidding after the firm approached the city through Orlinsky with its proposal to solve the sludge disposal dilemma.

"From a sheer bribery standpoint, the whole thing doesn't make any sense; he couldn't deliver, anyhow," said Michael Silver, a lawyer friend of Orlinsky, who noted that "the mayor and his two appointees could outvote him anytime" on the board of estimates. "If I were trying to get something done in the City of Baltimore, he's the last person I'd try to bribe."

News of the indictment was greeted with disbelief by Council Vice President Clarence (Du) Burns. "Everybody's surprised," said Burns, who represents the central city district that includes Orlinsky's home in Bolton Hill, a fashionable restoration area. "I would say his integrity is beyond reproach," Burns added. "As far as I'm concerned, he's a good, clean-cut guy."

Orlinsky, a native New Yorker and the son of a Biblical scholar, graduated from Johns Hopkins University and the University of Maryland Law School. He served in the House of Delegates before being elected in 1971 to the council presidency, which now pays $39,500 a year.