Ed Appling pulls his National Park Service pickup to the side of the road a few hundred yards east of Olmsted Point. Solemnly, he points to a small brass plate fastened to the granite wall on the opposite side of the road.

The memorial marks the place where Barry Hance was crushed by an avalanche while clearing snow on June 13, 1995. It's too small to be noticed by passing motorists but, for Appling, it's a reminder of winter's powerful grip on Tioga Road.

Cars fill the Olmsted Point turnout every summer as people stop to marvel at how ancient glaciers carved out the walls of Tenaya Canyon, which leads the eye west to the rear side of Half Dome. But as the sun's heat radiates from surrounding granite, few think of how the snow and ice, which created the stunning vista, also create danger for snow- removal workers who labor for weeks and sometimes months to clear the road each spring.

Olmsted Point is the most dangerous of 23 avalanche chutes in the park, says Appling, 53, a roads supervisor for Yosemite National Park. To reach the viewing area, engineers carved the road into the side of a granite dome.

Heavy, wet snow clings to the dome in winter like cookie dough, often reaching a depth of 12 feet. During the spring melt, water collects under the snow and forms ice on the granite. Cutting through the snow at road level, which starts in April, removes support for the snowpack on the dome and tons of snow can slide down without warning.

Workers follow strict safety guidelines. Spotters watch the snow for signs of danger. Crews may use explosives to loosen unstable chunks of snow or melt it with applications of charcoal dust or water.

Appling takes pride in clearing the road, just as his father, Aldon, took pride in building it. The 21-mile middle section, from the White Wolf turnoff to a point about 3 miles east of Tenaya Lake, was a dirt road until it was rebuilt in 1957-61 on a new alignment. The old route passed north around Olmsted Point, where there is no avalanche danger. The new alignment follows a southerly path across solid granite to reach Tenaya Canyon.

"My dad was a driller for the blasting," Appling says. "The workers lived in Tuolumne Meadows all summer, and we'd drop my dad off at the work site every morning."

While playing with the children of other workers, Appling often was reminded of work on the road.

"The explosions," he says, "sounded like sonic booms."