Racine, C.H., and M.E. Walsh (1994) WP in sedi-
1994, and 1995), waterfowl population aerial and
ground censuses (1994 and 1995), and radio-
ment. In Interagency expanded site investigation:
telemetry locational data for 127 radio-collared
Evaluation of white phosphorus contamination and
ducks, 14 eagles, and 20 shorebirds (1993, 1994,
potential treatability at Eagle River Flats, Alaska
and 1995). About 39 primary coverages compose
(C.H. Racine and D. Cate, Ed.). CRREL Contract
the master ERF GIS database.
Report to U.S. Army Garrison, Alaska, Director-
Secondary coverages are also listed and may be
ate of Public Works, FY93 Final Report, p. 153
important for future decisions at ERF. These
184.
include sedimentationerosion studies, remedia-
To characterize the distribution and concentra-
tion tests, water quality and weather monitoring
tions of WP in Eagle River Flats, over 2000 sedi-
sites, and GPS ground-truth data. To help accom-
ment samples have been collected and analyzed
plish the selection of appropriate cleanup method
from a range of habitats, including ponds and
technologies, researchers will need to supply cri-
marshes, mudflats, and distributary channels,
teria for determining where their technologies
over the past 3 years. Surface sediments (the top 5
would and would not work. The third decision
cm) were hand-scooped from the bottoms of
concerning evaluation of cleanup success involves
ponds for analysis. In 1993 a composite pond
the design of endpoint criteria to be entered into the
sampling technique and field screening method
were successfully tested. Concentrations of WP in
database.
sediments ranged from less than the detection
limit of 0.00088 g/g to over 3000 g/g. The con-
Racine, C.H., B. Tracy, and P. Berger (1998) Map-
centration frequency distribution for surface sed-
ping and classification of intermittent and perma-
iment samples follows a log-normal distribution.
nent ponds on Eagle River Flats. In Interagency
Most sample concentrations are in the range of
expanded site investigation: Evaluation of white phos-
0.0010.01 g/g, a relatively low level given that
phorus contamination and potential treatability at
Eagle River Flats, Alaska (C.M. Collins and D. Cate,
the lethal dose to a mallard is in the range of 6000
g.
Ed.). CRREL Contract Report to U.S. Army,
Alaska, Directorate of Public Works, FY97 Final
Initial screening for WP in the sediments of
Report, p. 101114.
seven pond areas was conducted in 1991 at 25-m
If ponds with sediments that become desatu-
intervals along transects through each pond area;
rated in some years can be identified, it is cost
two of the seven pond areas (Area C and the
effective to allow natural attenuation of white
Bread Truck Pond) were identified as being high-
phosphorus to occur in these ponds, rather than
ly contaminated with WP (over 50% of the sam-
actively dredge, pump, or drain. In 1993, about
ples were positive, and the concentration of at
least one sample was over 1 g/g). Another pond
350 ponds covering 125 ha were photointerpreted
from orthophotos and digitized into a GIS data-
area (Area A) was only lightly contaminated.
base (ARC/INFO). Each pond was classified as
Indicator conditions of WP presence (crater cover,
permanent (ponds that do not dry out in any year)
carcass density, and water depth) were mapped
or intermittent (ponds that dry up in some years
and used as an aid in selecting new areas for
and where white phosphorus could potentially
additional sampling. During 1992 and 1993, addi-
tional sampling of Area A failed to show WP hot
sublime). In mid-July 1997, we conducted a field
spots, despite the presence of carcasses. A new,
accuracy assessment of this classification by visit-
highly contaminated pond area on Racine Island
ing 35 mapped ponds during a "dry period" (i.e.
was identified in 1993 on the basis of the large
60+ days without a flooding tide) and determined
numbers of duck carcasses found there.
how much of the surface was flooded, as well as
About 100 sediment samples from mudflats
other pond characteristics. The results showed an
(without standing water but with high crater
86% accuracy in the original classification, well
within the Federal Geographic Data Center's level
cover) were collected and showed less than 10%
of acceptance. In addition, we tested the use of
positives and low concentrations. To see if WP is
digital multispectral video (DMSV) images for au-
being transported out of the two contaminated
tomated mapping of permanent and intermittent
ponds, 87 sediment samples were collected along
ponds and for monitoring pond drying and other
the lengths of four distributary channels; only
conditions. Classified DMSV imagery was also
two tested positive for WP (in pools at the head of
used successfully to monitor both headward and
these channels).
lateral gully erosion between 1993 and 1997.
55
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