1. Landslides and Ground Water Permeability with Respect to the Contact of Glacial Lake Vermont and the Champlain Sea Sediments at Town Line Brook, Winooski, VT Michala Peabody Lara Vowles

2. Location Map

3. Town Line Brook Timeline 13,000 years ago retreat of Laurentide Ice Sheet developed Glacial Lake Vermont 12,000-10,000 years ago continued retreat of Ice Sheet permitted formation of The Champlain Sea Land rebounded causing the formation of Lake Champlain Town Line Brook developed creating a v-shaped valley running into the Winooski River.

4. Objectives Determine the Exact contact between Lake VT and Champlain Sea Determine how different sediments affect groundwater permeability Determine how this affects landslides

5. Methods Dig out trenches to find contact Use pocket vane tester to determine shear strength of sediments Use level & rod to create a cross section of area Obtain a core sample of contact Cross Section

6. Results...starting @ top Champlain Sea sediments: alternating fine sand and silt layers Top Hole

7. Results...cont. Middle HoleBottom Hole

8. Results...Contact! Distinct layer of oozing slime consisting of fine silt and sand Situated above hard packed Glacial Lake VT sediments

9. The Core Check it Out!!

10. Results...below contact Hard packed Thin varved layers Alternating red / gray Creation of mini-landslide developing at contact

11. Mini-Landslide Created by Lara & Michala...oops

12. Aerial Photographs 1962

13. Aerial Photographs 1988

14. Aerial Photographs 1999

15. “In landslides, as in life. It’s the little things that count.” ~S.P. “Slump or Slide, Density Decides”

16. Much Thanks to Stephen Wright!!