One of the biggest, most lavish international arts festivals ever to be held in the United States is being organized as an official adjunct to the 1984 Olympic Games in Los Angeles.

The $10 million, 10-week exhibition of 100 events in dance, music, theater, painting, sculpture, films and other disciplines will include a $1.5 million exhibition of 75 Impressionist masterworks from the Louvre; the Royal Opera of London performing Benjamin Britten's "Peter Grimes" and other works; and what an organizer called avant-garde "high-risk stuff," including naked Japanese dancers performing while hanging by their heels from wires.

"This will be the most important arts festival in the world in 1984," said Robert J. Fitzpatrick, director of the festival. "It will be an intelligent and happy preface to the Games . . . We're not trying to compete with the sports events."

The festival will be held at locations throughout the Los Angeles area beginning June 1, 1984, with performances of choreographer Pina Bausch's Wuppertaler Tanz Theater of Germany on a stage completely sodded with live grass, and including a gala performance by the Los Angeles Philharmonic Orchestra and concert artists from around the world at the 18,000-seat Hollywood Bowl just before the Games open July 28.

Both the Games and arts festival finish Aug. 4. Art competitions and exhibitions have been part of the Olympics since 1912, but seldom on the scale being planned in Los Angeles. The charter of the International Olympics Committee calls for art exhibitions of "an equal standard to that of the sports events."

When he began organizing the arts festival several years ago, Fitzpatrick received a call from Paul Guimard, a cultural counselor to French President Franc,ois Mitterrand, asking if he was free for lunch on Thursday.

"I thought he was going to be in L.A., so I said yes. He said, 'Fine, be at the Elyse'e at 11:30,' " said Fitzpatrick. That lunch led to an agreement to bring the works from the Louvre for a special exhibition, which Fitzpatrick said the French government is subsidizing "substantially."

"The foreign governments take an unbelievably intense interest in how they're going to be culturally represented," said Fitzpatrick, a former Baltimore city councilman and Johns Hopkins dean who now, as arts festival director, has his business card printed in dozens of languages and keeps a chauffeured limousine on 24-hour call. He is president of California Institute of the Arts, a private arts college in Valencia.

In traveling the world for the Olympics, he said, "I was a little unnerved and surprised that the attention being paid went all the way to the top levels of government." When in Guinea signing up Les Ballets Africains, President Ahmed Se'kou Toure' invited him to lunch--"not just a courtesy; he wanted to be assured how African culture would be represented. I told him we've given a prime period of time to them."

Fitzpatrick is signing his biggest contracts with major countries that have hosted the Olympics--England, France, Italy, Canada, Mexico, the Soviet Union, Japan, Germany, Australia, Greece and others. All 150 countries represented in the Games will participate in an International Festival of Masks in the L.A. Craft and Folk Art Museum.

Fitzpatrick's biggest coup so far is the $3.5 million contract with the Royal Opera of London, which will also perform Puccini's "Turandot" and Mozart's "Die Zauberflote." He attended music festivals all over the world to select winning chamber music groups and opera companies.

Fitzpatrick wants unconventional events, too: "The chemical balance of putting a festival together is important. You need risk and excitement, you've got to catch people off guard, seduce them."

Thus Fitzpatrick signed up Japan's Sankai Juku dance company after he saw them last summer performing a work in Scotland in which one member of the company lay on the ground blowing a horn in front of the Edinburgh city hall while four others--naked, covered in white powder and hanging upside-down by their heels from wires--were winched down the fac,ade of the building.

"It was stunning--seeing the looks of stunned disbelief on the faces of the city council as they looked out the windows," Fitzpatrick said. In Los Angeles, he plans to have the dancers winched down the outside of the Dorothy Chandler Pavilion of the Los Angeles Music Center, site of the annual Oscar ceremonies.

Shakespeare will be performed in foreign languages--with no English translation. Fitzpatrick theorizes translations would be distracting, but admits there are "a lot of risks" in this plan. He thinks it will work with plays "somewhat known to the audience."

Russia's Rustaveli Theater will perform "Richard the Third" in Russian and Georgian; France's Ariane Mnouchkine and her Theatre du Soleil will perform "Richard the Second" in French and in the Japanese samurai style, and "Twelfth Night" in French in the Indian Kathkali style. Fitzpatrick is negotiating with the Piccolo Theatro of Milan to do "The Tempest" in Italian.

He hopes to have Greek tragedy, too, and is negotiating with the British National Theatre to do the "Oresteia."

Eighteen dance companies from around the world have been signed up, including the Royal Winnipeg Ballet of Canada.

The festival will include dozens of "mini-festivals" of chamber, contemporary, jazz and country-western music.

American artists will be strongly represented. Ten murals were commissioned for various spots in the city and 15 American artists have produced Olympic posters on commissions. Los Angeles sculptor Robert Graham will create a $250,000, 25-foot bronze gateway to be placed in front of the Los Angeles Memorial Coliseum, where the field events will be held. The Museum of Contemporary Art in Los Angeles will present an exhibition on "The Automobile and Culture."

The annual Los Angeles International Film Exposition will become part of the festival with a marathon showing of 30 films using sports as a metaphor for the human condition.

The festival is sponsored by the Times Mirror Company, which donated $5 million. Other major companies and foreign governments made substantial contributions, Fitzpatrick said. CAPTION: Picture, Sketch of Robert Graham's $250,000 bronze gateway, with the female and male torsos, to be placed at the Los Angeles Coliseum for the 1984 Olympics.