Figure 4. Large excavators dug
the trench to a typical depth of 6 to 8 feet. The photo shows a
fresh opening in glacial till. This stony material was released directly
from melting glacial ice. Many large boulders had to be removed from the
trench, as seen in the background to the left of the excavator. The pool
of water in the foreground resulted from digging below the water table.
Last updated on October 6, 2005