Officials say weather is to blame for the slide.
It happened about 15 miles east of Briceburg.
Crews will finish up initial scaling of the slide area this week, but it could take another week to remove all the material.
Caltrans hopes to reopen the roadway to one-way traffic by next week.
In the meantime, drivers can take a detour at Foresta and El Portal Roads.
This runs parallel to the slide area.