identical manner as described for 1-44 (Fig. 5).
at each sampling location: 015 cm, 1530 cm, 30
From the condition of the target vehicle and the
45 cm, and 4560 cm. A fifth sample from a 105- to
concentration of surface debris, we thought that
120-cm depth interval was collected with a post
this area had much less use than did the corre-
hole digger, after the 45- to 60-cm-depth sample
sponding target in range 44.
had been removed. In all, 280 soil samples were
collected from 14 grids containing 56 sampling
Location 248
points by two CMS sampling teams in a period of
We established a second range 48 location, des-
a day and a half.
ignated 2-48, next to an abandoned target area.
We should note that Zip-Loc plastic bags were
A.R. Smith and personnel from CMS Corporation
used for sample collection, rather than glass bottles,
told us that a target vehicle had been located here,
for two reasons. First, our experience told us that
some time past, but it had subsequently been
rather large samples with substantial homogeniza-
removed. The large pieces of a target vehicle that
tion were necessary to produce representative
littered the immediate vicinity provided evidence
subsamples for discrete locations. This was much
for this conclusion. The ordnance debris was
easier to accomplish using plastic bags. Secondly,
largely from mortar rounds, which are typically
collecting samples in an area contaminated with
filled with Composition B. No debris from 66-mm
UXO was much easier to do using plastic bags. Re-
M72 LAW rockets was observed at this site, indi-
search conducted by Parker et al. (1990) has dem-
cating that it was an older target area, used before
onstrated that polynitroaromatics and nitramines do
the LAW rockets were introduced. Four sampling
not sorb strongly to plastics. In addition, we did not
grids were established adjacent to this location in
observe any tendency of fine particles to adhere to
an identical manner to those in 1-44 and 1-48.
the inner surfaces of the bags.
Location R48
Homogenization and subsampling
The third sampling location in range 48 was in
for discrete soil samples
an area that was free of target debris and had a
Surface (0- to 15-cm) samples were returned to
low concentration of munitions debris. This loca-
CRREL in their entirety. For other samples, we
tion was surrounded by target vehicles, the closest
homogenized the soil in the bags, in an area just
being about 30 m distant. Thus, soil samples from
off the firing range, by shaking and pouring the
this sampling location served to indicate the level
material within the bag. A subsample of several
of residual contaminants in the firing range at large,
hundred grams was then retained and shipped to
but at a distance from individual target vehicles. A
CRREL for analysis.
single 5- 5-m grid was established at this position,
Once at CRREL, the samples were further
with four sampling points located as described
homogenized by shaking and pouring within the
above. This location was designated as R-48.
bags, and a 35-g sample was removed and air-
dried overnight in weigh boats. Because there had
been little or no rainfall at Fort Ord for some time
Soil sample collection
All soil samples were collected by EOD person-
prior to sampling, and since the soil there is largely
nel from CMS Corporation. At all designated sam-
fairly coarse sand, the soils from the first four
pling points, soil was excavated by hand digging
depth intervals were quite dry. Soil from the 105-
in 15-cm-depth intervals. The soil for a given depth
to 120-cm depth had a higher moisture content,
interval was mixed in place with a small hand-
but even so, it was generally only about 3% on a
held shovel. This method worked well for the dry,
dry weight basis.
sandy soils at this location and it minimized the
After dry weights were obtained, air-dried soils
need for collecting very large portions in a sepa-
were further homogenized by thoroughly mixing
rate container. Approximately 1 kg of material was
the material in the weigh boats with a spatula. A
shoveled into a 1-gal. Zip-LocTM bag. The bag was
2.00-g portion was then placed in a 22-mL glass
closed and the remaining soil from that depth
scintillation vial for extraction and analysis by
interval was removed from the hole. The EOD in-
reversed-phase high-performance liquid chroma-
dividual then treated the soil from the next depth
tography using a UV detector at 254 nm (RP-
interval identically, being careful that material
HPLC-UV) (SW-846 Method 8330). Several dupli-
from the sides of the hole did not fall in from above.
cate samples were prepared, as well, for each batch
This kept soils collected at depth from being con-
of soils processed. The remaining material was
taminated by material from nearer the surface.
retained in 22-mL glass vials for additional char-
Samples were collected from the following depths
acterization.
7
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