Corps of Engineers, Alaska District, and U.S.
remotely controlled drill and sampler that
Army, Alaska. September.
may be used to assess vertical extent in the
This report presents the results of the Feasibili-
future.
Off-site migration of WP. This data gap will
ty Study (FS) for Operable Unit C (OUC) on Fort
not be addressed in 1995.
Richardson, Alaska. Operable Unit C represents
Waterfowl and predator use in several areas.
the Eagle River Flats (ERF) and the former open
Telemetry studies and aerial surveys will
burning/open detonation (OB/OD) Pad area at
performed again this year to track how fre-
Fort Richardson. The U.S. Army Corps of Engi-
quently the ducks and eagles use the areas of
neers (COE), Alaska District, on behalf of the U.S.
the ERF.
Army, Alaska (USARAlaska), contracted with
Lethal effects to waterfowl and predators in
CH2M Hill to prepare the FS under Delivery
several areas. Telemetry studies will be per-
Order 1, Modification 5, of Contract Number
formed this year to estimate the mortality
DAC8595-D0015.
rate across the ERF.
Off-site receptor exposure and effects. This
Site description and contamination
data gap will not be addressed in 1995.
Eagle River Flats is an 876-ha estuarine salt
Site characterization data needed to address
marsh at the mouth of Eagle River. Approximately
25 targets placed in ERF have been used for artil-
the applicability of remedial technologies are out-
lery training since 1949, creating thousands of
lined. Broad information categories include phys-
craters in the wetlands and associated mud flats
ical, chemical, biological, habitat, and replace-
and leaving an estimated 100,000 unexploded
ment site. These are charted against the potential
mortar and artillery shells buried in the shallow
remedial technologies: dredging, pond drainage
subsurface. Although ERF is an active impact
with natural attenuation, natural attenuation
area, it remains a productive wetland that serves
alone, AquaBlokTM, liners, hazing, methyl anthra-
as an important staging ground for migrating wa-
nilate, cap/fill, excavation, and land purchase at
terfowl during the spring and fall migrations.
a replacement site.
ERF also supports local populations of fish, birds,
The qualitative evaluation that was performed
mammals, and macroinvertebrates. A series of
to determine the importance of information in
ponds distributed throughout ERF provide excel-
deciding which technologies are applicable to
different areas of the ERF is summarized. For
lent habitat for dabbling waterfowl.
example, site access is an important issue in
Since the initial reports of elevated waterfowl
determining whether dredging can be performed
mortality in the early 1980s, a multidisciplinary
in an area. Because pilot tests for several remedial
investigation has been conducted to identify the
technologies are being performed during the
cause of the mortality (shown in 1990 to be white
1995 field season, the determination of critical
phosphorus [WP]), the extent of the WP contamina-
data should be reconsidered before significant
tion, and the potential effects of WP and other mu-
studies are initiated. More focus is needed on spe-
nitions on the biota in ERF. WP was released into
cific data needs for likely technologies and ERF
ERF by ordnance used to create smoke for marking.
remediation areas before a cost-effective study of
WP that does not fully oxidize can remain as parti-
the site characteristics can be prepared.
cles in the sediment. Ingestion of WP particles by
The qualitative analysis that was performed to
feeding waterfowl has created high levels of mor-
identify data needed to support a remedial action
tality. Birds have been observed to die within min-
decision is also summarized. The analysis used
utes to hours of ingesting WP in a number of ponds
criteria to address the feasibility of remedial action
in ERF.
that were based on nine evaluation criteria of the
The results of the investigations to characterize
USEPA for choosing a remedial action under
the nature and extent contamination and the
CERCLA. Particular aspects of the ERF--such as
baseline risk assessment for the site were presented
the importance of being able to operate a technolo-
in the OUC remedial investigation (RI) report.
gy remotely to reduce the potential safety hazards
The findings documented in the RI report are
of personnel operating in an area containing unex-
based primarily on data collected before imple-
ploded ordnance (UXO)--were emphasized.
menting the Comprehensive Environmental Response,
Compensation, and Liability Act (CERCLA) process at
CH2M Hill (1997) Operable Unit C. Final Feasi-
OUC. Compilation and review of all the data have
bility Study Report. Contract Report to U.S. Army
led to the following conclusions:
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