The Federal Communications Commission has paid $175,000 to consultants to help the agency lease office space in the Washington area -- work the General Services Administration would have done without charge, commission officials have acknowledged.

Most of the money -- $127,300 this year -- went to Computer Science Corp.

for "office landscaping" in buildings the agency currently leases in the District, but between $25,000 and $30,000 went for the design of office spaces in a controversial Arlington high-rise that the agency has not been authorized to rent.

The payments also included about $50,000 -- at $680 a day -- to the Washington real estate firm of Julien J Studley, which was asked to help the agency find additional office space.

Thomas Campbell, the FCC's associate executive director for operations, said that both firms were chosen without competitive bidding and at the suggestion of one of his assistants who used to work for Computer Science .

"This was no sweetheart deal," said Campbell. "They are reputable firms that have done business with the government before, are on government-approved lists and were hired at rates similar to those charged other federal agencies." l

Questions about the propriety of the contracts and the agency's controversial efforts to move its headquarters and 1,700 employes to Arlington from downtown Washington are expected to be raised in the Senate today when several senators plan to introduce amendments to the FCC's 1981 appropriations bill in an effort to block the move.

A two-sentence rider added to the bill by the House would permit the FCC to lease its own office space, bypassing normal federal leasing procedures and allowing the FCC to ignore its 1934 charter, which requires the communications agency to have its headquarters in the District.

Sen. Max Baucus (D-Mont.), chairman of a Senate Judiciary subcommittee, has been critical of the consulting contracts and has announced he will hold hearings on them Oct. 2. Baucus has questioned the cost of the contracts, the FCC's failure to seek competitive bids and whether the FCC should do its own leasing.

FCC documents already given to the senator's staff show that in the past three years the number of FCC contracts put out to competitive bid has declined drastically, from 69 percent in 1977 to 13 percent during the current fiscal year.

The FCC's Campbell said that while the number of FCC contracts that are awarded on a noncompetitive basis may appear high, their dollar amount is relatively small. "Only about 48 percent of the $1.8 million in contracts let so far this fiscal year have been sole source," Campbell said. Last year, about 60 percent of the FCC money spent on contracts was awarded without competitive bids, he said.

The 30-story Rosslyn building where the FCC would like to move was challenged unsuccessfully in court last fall by two federal agencies, the Department of Interior and the National Capital Planning Commission. They contended that the huge, twin-tower complex -- which will be the tallest in the Washington area -- would ruin the skyline of the nation's capital.

Their claims were rejected by the courts.

Campbell said the FCC knew of the federal suit when it made inquiries about leasing space in the building. "We carefully didn't begin actual negotiations until after the suit was settled," he said.

Like many federal agencies in Washington, the FCC has long wanted more space in one location because its employes are scattered in buildings around Washington. "I don't say our problems are greater than those of other agencies . . . but our chairman (Charles Ferrie) felt our mission was being impaired . . . and we needed to do something immediately," Campbell said.

The FCC began designing a new headquarters in Rosslyn, he said, even though it lacked congressional approval or funds for the move because "we couldn't afford to wait 90-120 days longer," the time he said competitive bidding would take.

The Arlington building where the Fcc wants to move is under construction and the FCC needed to act quickly to plan the layout of the floors it would occupy, Campbell said. "If we don't go into this building it (the money spent on office designs) will appear to have been for naught . . . we had to gamble a bit."

A spokesman for Computer Science said the firm "does not discuss client matters . . . but this is just a normal, above-board contract."

Barbara Pryor, broker for Studley, said "I don't think $680 a day is high. As a matter of fact it's low . . . and the Twin Towers (the Rosslyn high-rise project) which I knew was coming 11 years ago, is one of the best deals I've ever made in my life. If the FCC doesn't lease this, it will cost the taxpayers $15 million compared to the rental figures the FCC would pay . . . around Washington with the GSA looking for space for it."

She said she has only been paid by the FCC for finding office space in Gettysburg and downtown Washington, and will not be paid for a move to Rosslyn because the building's owner, Stanley Westreich, would pay her a normal broker's commission.

"I don't know what Congress is looking at. This has got to be the dullest scandall in town. I'm scrupulously honest and so is the Twin Towers owner." s