By BETH QUINN

Rafters and kayakers who want to measure themselves against Southern Oregon's most remote and challenging whitewater river could soon need an advance permit.

Illinois River managers at the Siskiyou National Forest are laying the groundwork to limit entry as early as the year 2000 with a 10-page, 70-question survey mailed to 180 whitewater enthusiasts who've led trips on the remote river that cuts through Josephine County's Kalmiopsis Wilderness.

"We probably will by the end of next year hit the trigger to institute a limited permit system," said Don McLennan of the Siskiyou forest's Illinois Valley Ranger District. "The use has grown dramatically starting in the late 1980s."

The trigger specified in the river's 1985 management plan is two consecutive spring float seasons with three or more launches per day on 10 or more days. This year 13 days exceeded the three-party limit. On one day, 10 separate float trips launched, and the highest use came on two days when a combined 13 separate float parties saw 64 river runners on the Illinois.

Those numbers may seem low in comparison with the nearby Rogue River, which has a daily launch limit of 120 people on non-commercial trips during the summer permit season. But knowledgeable river runners consider the Illinois a very special river.

"It's one of the only rivers in the continental U.S. where you can still expect a pristine whitewater-type river experience," McLellan said. "We really want to maintain that opportunity because you just can't find it short of going to Alaska."

The Illinois is also one of the most challenging whitewater rivers, with a series of rapids ranked Class 5 on a scale where Class 6 means risking death. And the deaths last March of two Illinois boaters who ignored warnings of unsafe conditions has led some to wonder if the permit proposal may be more about safety than numbers.

But McLellan says the wilderness law that decrees no developed campsites along the 30-mile Illinois River corridor also requires letting people risk their lives, even foolishly.

"We feel some responsibility, but the bottom line is that wildernesses and these kind of areas are set aside for people to test themselves," he said. "They're there for people to challenge themselves."

The March drownings have drawn the academic interest of Southern Oregon University social psychologist Karen Salley, who helped the Siskiyou forest develop the river survey. "I've always wanted to do some research on how risky decisions are made in outdoor adventure," she said. "Because researchers aren't usually out there to study it, we don't have any empirical information to understand what's really happening at the time."

Commercial outfitter Steve Welch of California's American River Touring Association, which runs four trips a year on the Illinois, favors a permit system to make sure the river remains wild.

"It is the experienced, seasoned river trip person who finds the Illinois. Those people are looking for that really special, remote, inaccessible, difficult-type experience," he said. "They need to do it now before people get used to three or four trips launching every Friday."