a. AquaBlok applied to Racine Island.
b. Geotextile barrier concept.
Figure 3. Physical barrier technologies tested at ERF.
Figure 4. Remote dredge operation in Pond 146.
any remaining contaminated sediments below
upland retention basin were successful in remov-
the depth that dabbling waterfowl can reach. The
ing white-phosphorus-contaminated sediments.
presence of unexploded ordnance dictated the use
However, dredging was slow and expensive. The
of a remote-controlled dredge to reduce the danger
associated placement of anchors and cabling sys-
to the dredge operator. A system was tested by
tems also exposed workers to potential dangers
CRREL in 1994 and 1995 and operated by a con-
from unexploded ordnance. Dredging was discon-
tractor in 1996 (Walsh, M.R., et al. 1996, Walsh
tinued after the 1996 season, with less than 0.5 ha
and Collins 1998). The dredge and associated
treated.
6