Deer Run Heights Landslide

Students in the Environmental Science Program at JSC have initiated research projects on the Deer Run Heights Landslide in Jeffersonville, VT. This work is being conducted in association with the Vermont Geological Survey and George Springston of Norwich University. Some of the activities include:

Measuring the rate of erosion along the slip face.
Measuring the changing angles and distance between trees on an active part of the slide.
Measuring pore water pressure in four monitoring wells.
Measuring slip along layers using time domain reflectometry in four monitoring wells.
Monitoring local precipitation and discharge along the Brewster River.
Conduct seismic profiling along the southern part of the ridge.

JSC Student Papers:

Adam Banks, 2009: Unstable lake sediments of Deer Run Heights represent a potential landslide hazard to the Cambridge Elementary School in Jeffersonville, Vermont.

Jay Cairelli, 2008: Downslope movement of trees and unconsolidated sediment at the Deer Run Heights in Jeffersonville, Vermont.

Michaela Forsberg, 2007: Glacio-lacustrine Deposits Create Landslide Hazards at Deer Run Heights in Jeffersonville, Vermont.

Amanda Wells, 2011: Correlating Precipitation to Changes in Groundwater and Stream Depth to Evaluate Slope Instability at Deer Run Heights in Jeffersonville, Vermont, 2011.

Christine Languerand, 2012: Seismic Refraction: A Geologic Exploration of the Jeffersonville Landslide.

Nate Weiss, 2012: Analysis of Hydrologic Factors at the Deer Run Heights landslide in Jeffersonville, Vermont.

Pictures of fieldwork and installations (below):

November 2009: Seismic profiling of the Brewster Uplands Community Trust Field
July 2009: Installation of four monitoring wells, three sediment cores, and two time domain reflectometry wells in the Brewster Uplands Community Trust Field
April 2009: Topographic mapping and installation of stream gages
April 2008: Spring melt and small slide above the Cambridge Elementary School
May 2007: Installation of four monitoring and time domain reflectometry wells above the Farara Slide

Online resources:

Water Measurement Manual, US Bureau of Reclamation, 2001

USGS Landslide Handbook at http://pubs.usgs.gov/circ/1325/

Pictures related to seismic profiling of the Brewster Uplands Community Trust Field (November 2009)

Seismic Profiling (November 2009).

Energy source is a sledge hammer with an impact activated switch.

Geophones are regularly spaced and connected via coaxial cable.

Setting up for the swing...

...and mpact on an aluminum plate.

Reading the results (note battery in cooler).

Geophones 1 throuhg 4 were disconnected.

Pictures related to installation of four monitoring wells, three sediment cores, and two time domain reflectometry wells in the Brewster Uplands Community Trust Field (July 2009)

Brewster Uplands Community Trust Field

Installation of time domain reflectometry wells (July 2009).

Geoprobe hammering of 2-3/8" ID casing to 91'.
Video: hammering the casing

Casing is flushed as hammering continues.

Flushing fluids recirculated in settling tank.

Clean water flush when drilling complete.

Flushing of well.

Hand-bailing of well.
Video: bailing technique

RG6/U Coleman coaxial cable, and weight,
placed into well.

Portland cement pumped into casing
as casing is removed.

Cement pumping system.

Casing removed and slid off cable.

Coaxial cable installed in wells to be used for time domain reflectometry using a Megger CFL535F cable fault locator. Installation and drilling by Specialty Drilling & Investigation.

Continuous split-spoon sampling and installation of monitoring wells.

Auger drilling.
Video: description of augers

Hammering a two-foot split spoon.
Video: hammering the split spoon

Split-spoon tube.

Shelby tube sampling at 69-71 feet.

Winter layer in silty fine sand at 42-44 feet.
Video: opening a split-spoon

Jon, Marjie, Les, and George on site.

Five-foot slotted screen piezometer.

Six feet of sand poured around slotted screen and capped with two feet of clay.

Monitoring well capped.

Well head in place.

Four monitoring wells were installed; three wells were drilled using split-spoon sampling. Installation and drilling by Specialty Drilling & Investigation.

Pictures related to initial topographic mapping and installation of stream gages

George and Ed install two stream gages; one uses pressure sensors (HOBO data loggers) within a threaded steel rod, the other gage measures stream stage in meters.
17 April 2009

Ed Robbins uses time domain reflectometry in order to identify breaks, or kinks,
in RG-58u cable inserted in four monitoring wells.
17 April 2009

Chris Brookfield, Sam Hellman, and George Springston
initiate topographic mapping along the ridge.
Oct 2008

Pictures related to Spring melt 2008

Approximately 100 m³ sediment moved downslope; note school in background.
12 April 2008

Base of slide seems to be assisted my the removal of sediment above a significant silt
and clay horizon. The small cavernous pores were commonly observed.
12 April 2008

Water permeates the top four meters of sands and conglomerates, then reaches a silty-clay horizon. The water-rich fine-grained sediment (including the silty-clay) flows downhill allowing semi-consolidated slumping of the sediments above. Click here to see a short video.
12 April 2008

Rip-rap at the base of the Farara slide appears to be directing water
away from the base of the slope. Stream gages will be installed upstream from this location.
12 April 2008

Jay Cairelli
12 April 2008

Expedition Drilling, in association with Wilcox and Barton, graciously provided the expertise required to drill four monitoring wells at the site (May 2007)