this study, both the initial research as well as the
Our opinion from this feasibility study was that
literature search were quite limited. The literature
dredging is feasible at the Flats. To obtain reason-
search topic was amphibious dredges, as this was
able production rates, the job will require a larger
the initial thrust of the study. Unfortunately, very
machine (20- to 25-cm pump) than originally esti-
little relevant information could be found on this
mated. Rather than design a machine specifically
subject. Concurrently, several basic texts and con-
for the job, we felt we should try to use as stan-
ference proceedings on dredging were reviewed.
dard a machine as practical to keep down costs
Also, all the current pertinent reports on the phos-
and facilitate repairs and replacement parts. A
phorus contamination problem at the Flats were
modular design would be ideal. We moved more
reviewed. With this background information, we
towards the use of a cable/capstan-propelled and
investigated possible dredge manufacturer con-
guided floating dredge rather than an amphibi-
tacts through the Thomas Registers and person-
ous unit, as a floating unit would be more readily
nel at CRREL who had worked with small dredges
available, less expensive, easier to operate, and
in the past. The objective was to determine
could be delivered sooner. Overall, if sufficient lo-
whether a small dredge capable of the special re-
gistical and construction support from the Direc-
quirements of operating in the Flats was available
torate of Public Works at Fort Richardson would
or could be easily modified from existing equip-
be available and procurement of the equipment
ment.
would not be delayed, conducting a demonstra-
A set of preliminary specifications was as-
tion project to confirm the feasibility of dredging
sembled and a list of prospective contacts was
as a form of remediation in the summer of 1994
compiled and the companies contacted. A brief
would be achievable.
explanation of the situation and the preliminary
specifications were sent to each contact. We re-
quested information on their product lines and
DREDGE SPECIFICATIONS
asked about visiting their facilities in the future to
discuss the project in more detail and to get a bet-
There were many factors to take into account
ter feel for their capabilities and strengths. A short
when developing the specifications for the dredge
list of five manufacturers was assembled and ap-
to be used in the pilot study at the Flats. Among
pointments to visit them were made. An informa-
these were environmental impact, the presence of
tion packet (Appendix A) was then assembled to
ordnance, personnel safety, and equipment
be given to each manufacturer during the visit.
transportability. No single dredge that we had seen
Samples of the ERF sediments consisting of pond
was able to address all these factors as they relate
bottom and shore material were bottled for the
to the Flats, so a specific set of criteria was drawn
manufacturers to give them a better feel of the
up for this application. In an attempt to minimize
material to be dredged. We then visited with each
the cost of the system, the specifications were kept
of the five manufacturers to discuss the feasibility
as close to standard as possible. However, some
of the pilot project.
deviation from normal was necessary.
All the manufacturers visited felt the job was
feasible. Their major concern, of course, had to do
Environmental considerations
with the UXOs. There were many questions that
The first factor addressed was the dredge's im-
needed to be answered before any of the manu-
pact on the environment. Eagle River Flats is an
facturers would be able to design a complete sys-
important migration route stopover, and as little
tem for the pilot project and estimate both price
permanent damage as possible should be done in
and productivity. These questions needed to be
the process of remediation. A small dredge will
addressed to the extent possible in the dredge
enable us to conduct the dredging process in a
specifications if the Project Manager decided to
more controlled, limited manner. The dredgehead
pursue the dredging option. A write-up of the
is specified as a shrouded, center-feeding auger
study, including methodology and conclusions,
that minimizes the dispersal of resuspended sedi-
the information packet given to the manufactur-
ment, therefore reducing the risk of redeposition
ers, unresolved questions, contacts, notes on the
of WP particles on the surface of the pond bottom
meetings, background information on each com-
(Sherman 1984). The small size also makes it air-
pany, and impressions of the visits and the com-
transportable by helicopter, thereby negating the
panies' capabilities by the two interviewers, was
need to channelize the Flats to move the dredge
given to the Project Manager.
from one area to another. The strategy developed
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