FORT DUCHESNE, Uintah County — As a 17-year-old living and working in the Amazon basin, Stan Brock found himself in need of a doctor after he was thrown from a horse.

"I had a head-on collision with the side of a corral," Brock said. "I was told, 'The nearest doctor is a 26-day walk away.' "

That incident and others stuck with Brock, now 74. Through the intervening decades, he managed a 4,000-square-mile cattle ranch in South America, co-hosted NBC's "Wild Kingdom" and made what he calls "a few bad movies."

"That is what I call my 'Frivolous Era,' " Brock said.

But he never forgot the lesson he'd learned in the Amazon: People in remote areas of the world have little or no access to basic medical, dental or eye care.

So in 1985, Brock founded the Remote Area Medical Volunteer Corps, the self-proclaimed "pioneers of no-cost medical care."

"This is what's important," he said, looking around the Ute Indian Tribe gymnasium in Fort Duchesne on Tuesday at the makeshift but well-equipped dental and optometry stations staffed by volunteer medical professionals from around the United States.

Many of the stations were in use, with Remote Area Medical volunteers providing free care to Native American patients from a number of tribes. The clinic, which opened its four-day visit to the Uintah and Ouray Indian Reservation on Sunday, had already treated 285 registered patients by Monday night and performed $123,979 in services at no cost.

"Nobody does this on the scale we do in this country," said Brock, whose group now spends 64 percent of its time working in the United States because of the rising number of people who are uninsured or underinsured.

Florine Sam of Duchesne, a member of the Tohono O'odham Nation, and her husband brought their four children to the clinic on Monday. Delbert Sam was laid off from his job as a diesel mechanic in June, his wife said, which left the family without insurance.

"It wouldn't have been so bad," Florine Sam said, "but they took the last (premium) payment out of his last check, which was $500."

The Sam children — ages 13, 9, 6, and 4 — have been accepted into the state's Child Health Insurance Program, their mother said. The family also qualifies for medical, dental and eye care through the federal Indian Health Service. But being seen at the IHS clinic in Fort Duchesne can be a frustrating experience.

"It takes about a week to two weeks to get an appointment," Sam said. "If you're five minutes late, they cancel your appointment so you have to reschedule."

On Monday, the family of six received free eye and dental exams. The Sams learned that their son, though he has better than perfect vision now, will eventually need glasses. Their teenage daughter got new glasses made while she waited to replace a broken pair she'd lost.

"She really needed them for school. She can see again," Florine Sam said, noting that while IHS will provide school-age children with glasses, they only get one pair a year, and it can take more than a month to receive them.

Remote Area Medical's visit to the reservation was suggested by Dr. Larry Zubel, chief of optometry at the IHS clinic in Fort Duchesne. Zubel said the clinic's two dentists approached him in the spring and said they were being inundated with patients, many of them children.

"We had more work than what we could do in the time we wanted to get it done," Zubel said, taking a short break from conducting eye exams at his station in the gym. "Stuff like dental work doesn't sit still. It gets worse if you don't work on it."

Zubel was aware of Remote Area Medical and sought the approval of the Ute Tribe Health Board to bring the group to the reservation for a free dental clinic. As luck would have it, the vehicle the volunteer group would bring to provide dental care carried optometry equipment as well.

Zubel said Remote Area Medical also agreed, at the health board's request, to provide free women's health exams for two days, including cancer screenings.

Florine Sam estimated that her family — already struggling to repay more than $1,000 in medical debt from last year — would have paid thousands of dollars for the care they received Monday. Equally impressive, she said, was the manner in which the volunteers treated their patients.

"I've been to many different hospitals and they have probably been the nicest, most accepting," she said. "Because it's free, you almost feel like you're imposing, but there was none of that. They thanked us for coming, which was kind of unusual.

"To find out they were all here on their own dime was just amazing. I figured it was a federal grant that was paying for it."

Brock, whose group held an eight-day clinic in Los Angeles earlier this month where nearly 4,000 volunteers provided $2.8 million in free care to 6,344 registered patients, said he's never applied for — and will not accept — government money to run his program.

"Most of our support comes from John Q. Public with $10 or $15 tax deductible donations," he said. "That is what is the lifeblood of this organization."