Glacier National Park road crews are chipping away at the infamous Big Drift - the only remaining obstacle to opening Going-to-the-Sun Road for the summer season.

Plowing equipment reached the 45-foot deep drift, located just east of Logan Pass, on Thursday and spent much of Friday cutting a swath through the drift, according to Amy Vanderbilt, the park's public affairs officer.

Park officials had been concerned about a large cornice that was hanging over the western edge of the drift, but it was knocked down with an excavator. No explosives were required to remove the cornice, as some had predicted would be necessary.

Sun Road is basically clear of snow all the way up to the drift from both the east and the west.

There will be a concerted effort this weekend to clear the parking lot at Logan Pass and to start preparing the Logan Pass Visitor Center for opening. Road crews also will clear rocks and other debris throughout the alpine portion of Sun Road over the weekend.

Lou Summerfield, Glacier's facilities chief, has said the road won't be open to vehicles over Logan Pass by May 16, the earliest date on record for opening the road, set in 1987.

But "there is potential" to have one of the earliest openings on record for the road, barring severe weather, avalanches or other unexpected problems on the road, Vanderbilt said.

This weekend, hikers and bikers can travel from the Avalanche Campground area all the way to Oberlin Bend on the west side of Logan Pass, and from Rising Sun to the East Side Tunnel east of Logan Pass.

All other park roads are open, Vanderbilt said.

Reporter Jim Mann may be reached at 758-4407 or by e-mail at jmann@dailyinterlake.com