A report has been released by the NYSDOT on the Scoby Hill Landslide which has impacted a 4.2-mi improvement project of Route 219. The report, dated May 20, 2008 was headed to an FHWA peer review panel.
The Feds were call in to help because of the unusual nature of the landslide. The slip surface is very deep, approximately 30-m (100-ft) below the surface and below all of the design phase investigations. And the remolded shear strength of the silty clay forming the slip surface was only 12-14 degrees.
Read on for more details of the slide. (Photo by NYSDOT)
Since I last posted about this landslide, ADOT has added several videos to their YouTube channel. It’s clear that this highway is going to be closed for the long term. ADOT and their on-call geotechnical consultant tasked with this project, Kleinfelder, are currently drilling boreholes to attempt to characterize the failure surface and determine what the geometry of the failure surface is. They are installing at least 10 inclinometers to try to determine the location of the slip plane or planes at depth and they have two extensometers to measure if any additional movement occurs. They are also performing LIDAR surveys as well. Check out the videos below.