The Washington Redskins will make a qualifying offer to running back John Riggins to protect their rights to him, but they still are undecided if they will bring him back for another season.

It also was learned today that veteran strong safety Tony Peters, who lost his starting job during the season, will not return to the team.

Kicker Mark Moseley, who finished the season by missing eight of his last 15 field goal attempts, might return, but if he does, it will be with lots of competition.

Quarterback Joe Theismann, whose status for 1986 is unclear, had the cast on his broken lower right leg removed Tuesday. It was replaced with a special brace that allows him to move his ankle, team doctor Charles Jackson said today.

This week, Redskins coaches and others in the organization have held preliminary personnel meetings. Although few decisions are final, it is clear that some changes will be made after the Redskins' 10-6 season. It was the first time in four seasons that they did not make the playoffs.

General Manager Bobby Beathard said this afternoon that the Redskins will send a qualifying offer to Riggins, their 36-year-old veteran who lost his starting job to George Rogers near the end of the season. The deadline for the offer is Feb. 1.

Riggins played the 1985 season with a one-year contract worth a reported $825,000 and is a free agent. The Redskins' qualifying offer is worth about $205,000, the minimum amount required on a qualifying offer for a 13-year veteran, Beathard said.

The offer is a "formality," Beathard said. It allows the Redskins to continue to negotiate with Riggins, allows them to match any offer he receives from another team through April 15 and allows them to sign him as late as June 1.

Riggins, who has made no public comments since the end of the season on his plans for 1986, has not spoken to the Redskins, Beathard said.

The Redskins apparently have not decided yet if they plan to ask him back. By sending him a qualifying offer, they buy more time to make a decision without making a firm commitment.

The Redskins have decided that Peters, 32, will not return for his 11th NFL season, sources said today.

A member of the Redskins since 1979, he never returned to his Pro Bowl form after he missed the 1983 season because of cocaine-related charges. In December, he said he thought his career might be over after he lost his job to rookie Raphel Cherry.

The Redskins plan to bring in several kickers, "probably six or seven or eight guys," for tryouts as competition for Moseley this spring, Beathard said.

Moseley, 37, who "disappointed" Coach Joe Gibbs with his performance late in the season, is likely to return, as things stand now, Beathard said.

Last month, Moseley acknowledged there were some within the Redskins organization who would rather not see him return. But that's nothing new; in 1982, he beat back strong competition from Danny Miller to keep his job, and, in 1985, he beat out Tony Zendejas.

It's uncertain whether that kind of competition will occur at quarterback this summer. Theismann, injured in November, apparently has lost the No. 1 job to Jay Schroeder, who led the team to a 5-1 record.

In an interview last week, Theismann did not mention a prospective return to the team.

However, his rehabilitation from his compound fracture continues to go well, Jackson said. Theismann is wearing a knee-to-foot brace that allows him to wear a normal shoe and move his ankle, Jackson said.

"It's basically like a cast," he said. "It still immobilizes the fracture, but it allows him to bend, to stretch his ankle. It's an improvement for him." At Theismann's request, Jackson said he would not discuss specifics of Theismann's rehabilitation. Originally, Jackson had expected Theismann to wear a cast until mid-February.