e. DD'. Located east of the landfill and includes data from GPR transect 94-85.
f. Westeast cross section EE'. Includes data from GPR transects 94-11 and 94-66 in
the northern portion of the site.
Figure 20 (cont'd). Six interpretive cross sections illustrating subsurface distribution of discon-
tinuous permafrost within the north-central cantonment area. GPR transect data used in each
cross section are indicated.
movement wherever they intercept the sub-
low and both the sediments and bedrock below
permafrost aquifer on the south. One of these ex-
them are frozen. Because of its lateral extent, the
tends from Finnegan's Pond on the northeast cor-
permanently frozen area forms a nearly impen-
ner of the landfill to the base of Birch Hill (Fig.
etrable barrier to ground water migration.
16). Two other smaller ponds lie within this thaw
Only in narrow, northsouth trending thaw
zone and appear to be where the ground water
zones does water move through this area; these
table comes to the surface. Hopkins et al. (1955)
thaw zones can strongly affect ground water