Bitter Springs landslide "deep-seated, quarter-mile wide"

 ADOT has just posted a video showing their test coring and geotechnical assessment of the slide block on Echo Cliffs that took out a section of US 89.    Steve Boschen, Deputy State Engineer describes it as a "deep-seated, bedrock" slide, with no evidence of movement of the toe of the slide downslope. That sounds like it may a Toreva block slide, so common in this region, but it's not immediately clear why there is no evidence of movement of the toe.    It appears the top of the slide is along the highway and Boschen said the "base of the slip is a quarter-mile wide."   Geotechnical engineers are monitoring the slide for continued movement.