Ski-mounted rescue workers using dynamite and heavy snowplows yesterday cleared tons of unstable snow from a ski resort where the worst of a series of High Sierra avalanches killed eight people.

Two remained missing and were "presumed dead," according to Placer County Sheriff Donald Nunes.

Four avalanches, triggered by nearly 13 feet of new snow dropped since Sunday by the most powerful spring blizzard in a generation, rolled into the popular resorts of Alpine Meadows and Squaw Valley Wednesday.

At Alpine Meadows, walls of snow nearly a mile wide rolled through an area known as Beaver Bowl, uprooting an A-frame structure and pushing it into the main ski lodge. Three bodies were recovered Wednesday. Yesterday, five other bodies were recovered, two of them buried under 25 feet of snow.

County Sheriff's Sgt. Steve Reader said rescue teams had abandoned the search at Alpine Meadows Wednesday night because of the probability of more avalanches. But 75 people, with trained dogs and long probing poles, resumed the search at dawn yesterday.

Workers tossed sticks of dynamite from helicopters onto dangerous snow cornices on the ridges of 8,500-foot Ward and Scott peaks. Others attacked giant snow drifts blocking the only road into the area, clearing the way for heavy equipment.

Controlled avalanches are routine in the resorts, with dynamite and howitzers routinely fired during the spring to break loose dangerous masses of snow. In a 1976 accident, three skiers were killed at Alpine Meadows in the same Beaver Bowl area.