A group of prominent businessmen is expected to decide within a month whether to start the United States Football League, a professional league that would play its games in the spring and would include a franchise in Washington, D.C.

The league's first season would be in 1983, with each club playing a 20-game schedule. The local team would be owned by Marvin Warner, a Cincinnati businessman, former ambassador to Switzerland under Jimmy Carter and a member of the Democratic National Committee. The team expects to play its home games at RFK Stadium, although no lease has been signed with the Armory Board.

"Yes, I think there will be a United States Football League, to start in the spring of 1983," said Judge Peter Spivak, acting chairman of the proposed league and one of the proposed co-owners of the Detroit franchise.

"A decision will be made within the next three to five weeks," Spivak said yesterday. "This is no pie in the sky thing. We've proceeded at a very cautious rate and the owners are at a point where they know they have to have money to risk and that they need quality players and coaches and good relations with the stadiums."

Spivak said the league, created in large part to take advantage of the expected boom in cable television, now has 13 commited franchises and could have 16 before applications are cut off. Those 13 owners have been asked to put up a $1.5 million letter of credit to confirm their intentions, according to sources.

Founders of the USFL have guarded carefully names of potential owners in an attempt to reduce publicity about the league until it was ready to operate. But according to a league memo, USFL owners include:

Boston--George Matthews, Boston banker and shipper, and Randy Vataha, former New England Patriot and a partner in a racquetball club business; New York--Walter Duncan Jr., Oklahoma City oilman; Tampa Bay--John Bassett, Canadian businessman and owner of the Memphis franchise in the late World Football League; Detroit--Spivak and Alfred Taubman, shopping center developer; Houston--Herbert Kohl, Milwaukee businessman and former supermarket chain owner; Denver--Willard Harris, Newport Beach, Calif., real estate and land developer; San Francisco--Jim Joseph, San Mateo, Calif., heavy construction and real estate; Los Angeles--Alex Spanos, Stockton, Calif., apartment complex developer; San Diego--Bill Daniels, San Diego cable television developer.

Other teams would be in Philadelphia, Chicago and Cleveland, but the names of their owners were not available. The league now is considering ownership applications from St. Louis, Seattle and Atlanta, according to sources.

The World Football League was the last pro football association formed to compete against the National Football League. But the WFL collapsed after two seasons, plagued by severe money problems, lack of television exposure and locations in minor audience markets.

Spivak says his league is taking steps to avoid the WFL's mistakes. All owners must have substantial wealth. Franchises would be located in all major markets. And, the USFL would play in the spring instead of competing directly with the NFL.

Instead of raiding the NFL for players, the USFL would compete for draft choices. It would conduct its draft in January, three months ahead of the NFL. Teams would select players through a territorial draft concept that still is being refined. That concept could mean that all Penn State, University of Maryland and University of Virginia players automatically would be the property of the Washington franchise. The rest of the roster would be filled by free agents.

The league already has an "approved coaches list" from which teams would be required to make choices. The league is placing heavy emphasis on big-name coaches to give it immediate credibility. Among the 47 names on a list obtained by The Post are George Allen, John Ralston, Hank Stram, Lou Saban, Red Miller, Dan Devine, Ted Marchibroda, Jack Pardee, John Madden, Ara Parseghian, Joe Paterno, Jackie Sherrill, George Welsh and Danny Ford. The league is prepared to offer coaches six-figure contracts and part ownership.

Other probable features of the league: no franchise fee; no-cut, guaranteed contracts for the best players; league-wide maximum player salary budget to control huge salaries; no player scouting staffs; specially priced family tickets; instant replay on controversial plays, and two-point conversions. Discussions already have been held with the NFL Players Association regarding its "percentage of the gross" concept pay scale.

The USFL is the brainchild of David Dixon, a New Orleans businessman who helped bring pro football there and was instrumental in the building of the Superdome.

Warner, the Washington franchise owner, formerly was a minority owner of the New York Yankees and a 48 percent owner of the Tampa Bay Buccaneers. He also breeds horses and is part owner of Kentucky Derby contender Stalwart.

Warner referred all comment on the league to Jimmy Gould, vice-president of the Warner-owned Warner National Corporation in Cincinnati. Gould said "if there is a league. . . George Allen won't be our coach. We respect and like him but we want to start with a concept that is completely different . . ."

Representatives of Warner have talked to the Armory Board about renting RFK Stadium, according to Robert Sigholtz, the Armory Board general manager. "This is a public facility and we can't show preference to one team or another," he said.