Francis Rizzo, who resigned last February as artistic director of the Washington Opera, has signed a three-year contract to fill the new position of artistic consultant to the Wolf Trap Foundation.

Rizzo was Wolf Trap's artistic administrator, with responsibility for operatic productions, from 1972 to 1979, before taking a full-time position with the Washington Opera.

"I don't know if I should be welcoming Frank aboard or welcoming him back," said Alan Rubin, foundation president. Besides opera, the new position will give Rizzo a role in Wolf Trap's programming of dance, symphonic music and special projects.

"My main job is to give advice directly to Alan Rubin," Rizzo explained yesterday. "It's not as if I'm going to call the shots; it's going to be counsel. My main focus will be on the serious side of programming. About the pop nights, I'm not going to say much; I don't even know much."

He said he thinks an ideal mix for the park's programming would be one-third pop, one-third serious and one-third "crossover" -- attractions like "Porgy and Bess" that will appeal to both pop and serious audiences.

When Rubin was chosen to head the Wolf Trap Foundation, he had no background in performing arts. He was selected for managerial skills -- "his ability to get all kinds of people to work together and to get funding," Rizzo said. Now, Rizzo has been chosen to supply the artistic expertise that Rubin lacks.

Rubin "does pose a lot of direct, sometimes disarming questions about what we do and why we do it," Rizzo said. "We have already started some healthy soul-searching, and we will be asking more basic questions at a two-day task force meeting in November."

Rizzo has often said he was "seduced" into taking a job at Wolf Trap in 1972 by Catherine Shouse, founder of the performing arts park. "Now, she has lured me back," he said. "One is still astounded at the clarity of her vision and the vigor that she summons to pursue it. It's one thing to find people who throw money your way, but true patrons of the arts, people with a special quality like Kay Shouse, Alice Tully or Lincoln Kirstein, are very rare."

Asked about the kind of programming he expects to promote, Rizzo recalled some of the distinctive operatic productions he brought to Wolf Trap in the '70s: Sarah Caldwell's production of Prokofiev's "War and Peace," the American premiere of Busoni's "Doktor Faust" and the world premiere of Stephen Douglas Burton's "The Duchess of Malfi," among others.

"Ms. Shouse was wonderful in allowing me to do many things that were not box-office events," he said. "All the things the experts advised against. Today, I am less inclined to propose things like that. I tend more and more to think we should attract as wide an audience as possible with populist programming of the highest quality. There is only one reason for a theater to exist, and that is to be full of people enjoying themselves."

His ideas on what can be done range from the relatively inexpensive (concert performances of opera with singing of the highest quality) to the wildly lavish. For years, he has dreamed of Wolf Trap as the ideal site for "an immense, spectacular 'Aida' that would draw enormous crowds and still be high art." That dream may now be one step closer to reality.

Under the contract, Rizzo said, "I will not have to go to an office every day, and I can continue to do free-lance work, which I enjoy, elsewhere."

Although he is no longer on the payroll of the Washington Opera, he is still working on many projects there. He will stage-direct this year's "Madame Butterfly" and he is preparing surtitles for all six of the company's foreign-language productions.

He also has written a number of articles for the Metropolitan Opera's souvenir programs and is preparing the surtitles for the Chicago Lyric Opera's production of Alban Berg's "Lulu."