With champagne and caviar in hand, more than 100 developers, government officials and professional golfers yesterday toasted the rolling hills of Avendel Farm to celebrate the ground-breaking of what will become the permanent home of the Kemper Open Golf Tournament.

Officials of the Kemper Open, which has been held at Congressional Country Club since 1980, expect the tournament to be held on the new course by 1986.

The 18-hole stadium golf course, which has been developed by the PGA Tour, will be called the Tournament Players Club at Avenel and will be built with movable tees to accommodate professional and amateur play and with a sloping, stadium-like effect at almost every green so spectators can view play.

The course is expected to cost $8 million -- about $6 million more than the average course, contractors at the ground-breaking said -- and cover 225 acres near the center of a high-priced residential development proposed by Potomac Investment Associates.

"We'll be able to have natural amphitheatres at practically every green," said PGA Tour Commissioner Deane Beman. "And the holes just fit in there as if they were meant to be."

"It's something that hasn't been done much," said Brit Stenson, construction manager for the project. "But this area -- with its terrain, its hills and its water supply -- has provided some very natural ways for people to view the game."

The golf course is part of what, at times, had been a controversial plan by Potomac Investment Associates to build 850 houses and townhouses, which will cost $70,000 to $600,000, in the rural area about 10 miles from Washington.

County officials who had questioned the project in its early stages said the golf course, proposed late last year, had been the selling point to neighboring residents who were concerned about a waste water treatment plant scheduled to be built in the development.

"It had a lot to do with mollifying concerns over the treatment plant," said Charles Gilchrist, Montgomery County executive.

In addition to the golf course, a practice green, public park and equestrian center will be included on the property. Construction on the golf course has begun and is expected to be finished by next summer, developers said.