CONCLUSIONS
residues with approximate surface concentrations about
20% of RDX.
This study demonstrates the utility of using snow
While we detonated only three 81-mm mortar rounds
surfaces to determine the amounts of explosives resi-
using C4, and two 60-mm mortar rounds without C4, it
dues left behind after military munitions detonate. The
appears that more RDX is deposited when C4 is used.
pristine snow surfaces provided a matrix free from resi-
This very preliminary result should be verified by deton-
dues of previous detonations and free of soil compo-
ations of the same munition with and without C4.
nents. The soot produced from the detonation of TNT
gave us a visual pattern of deposition on the white sur-
face. We easily collected residues from contaminated
LITERATURE CITED
snow surfaces using an unpainted aluminum snow shov-
el. The ability to efficiently collect a thin layer of snow
Collins, C.M., and D.J. Calkins (1995) Winter tests of
allows sampling of a large percentage of the contami-
artillery firing into Eagle River Flats, Fort Richardson,
nated surface while minimizing the volume of snow-
Alaska. USA Cold Regions Research and Engineering
melt produced. Because the pattern of deposition is quite
Laboratory, Special Report 95-2.
heterogeneous, collection of a large portion of the
Fine, D.H., W.C. Yu, E.U. Goff, E.C. Bender, and D.J.
affected surface area is necessary to ensure that sam-
Reutter (1984) Picogram analyses of explosive residues
ples are representative.
using the thermal energy analyzer (TEA). Journal of
The results of mortar round detonations at Camp
Forensic Sciences, 29(3): 732746.
Ethan Allen demonstrated that very little soil is thrown
Jenkins, T.F., M.E. Walsh, P.G. Thorne, S. Thibou-
out if the detonations are conducted where the snow
tot, G. Ampleman, T.A. Ranney, and C.L. Grant
covers a frozen surface. On the other hand, the experi-
(1997) Assessment of sampling error associated with
ment at Fort Drum showed that if the study was con-
the collection and analysis of soil samples at a firing range
ducted late in the season, when the soil surface has
contaminated with HMX. USA Cold Regions Research
thawed, soil particles were deposited on the snow along
and Engineering Laboratory, Special Report 97-22.
with residues of the detonation. This complicated the
Jenkins, T.F., M.E. Walsh, P.G. Thorne, P.H. Miyares,
analytical chemistry and resulted in an increase in the
T.A. Ranney, C.L. Grant, and J. Esparza (1998) Site
uncertainty associated with determinations. Therefore,
characterization at the Inland Firing Range Impact Area
we recommend that such tests be conducted during mid-
at Fort Ord. USA Cold Regions Research and Engi-
winter, when the surface soils are frozen and frost pene-
neering Laboratory, Special Report 98-9.
tration is at its maximum. Because TNT and other resi-
Miyares, P.H., and T.F. Jenkins (1991) Improved salting-
dues are susceptible to phototransformation, and the
out extraction/preconcentration method for determina-
presence of black soot on the surface enhances melt-
tion of nitroaromatics and nitramines in water. USA Cold
ing, these studies should be conducted on overcast days
Regions Research and Engineering Laboratory, Special
and samples should be collected as quickly as possible
Report 91-18.
to ensure that residues do not penetrate deeper into the
Phelan, J.M., P.J. Rodacy, and J.L. Barnett (in prep.)
snow pack, thereby minimizing the depth of snow that
Explosive chemical signatures from military ordnance.
must be sampled.
Sandia National Laboratories Report.
Because we only collected samples from five deton-
U.S. Army Materiel Command (1972) Engineering
ations in this study, the masses of residues that we report
design handbook: Principles of explosive behavior. AMC
should be considered preliminary. In fact, the surface
Pamphlet 706-180. Washington, D.C.
concentrations and estimates of percent residuals dif-
U.S. Environmental Protection Agency (1994) Nitro-
fered substantially from test to test, particularly for the
aromatics and nitramines by HPLC. Second Update
C4 initiated detonations at Camp Ethan Allen. Never-
SW846 Method 8330, September.
theless, the following generalizations can be made. First,
U.S. Environmental Protection Agency (1999) Nitro-
it appears that a higher percentage of TNT is consumed
aromatics and nitramines by GC-ECD. Fourth Update
in detonations than RDX when the main charge is Com-
SW846 Method 8095.
position B. This appears to be true whether C4 was used
Walsh, M.E., and T.A. Ranney (1998) Determination
to detonate the mortar rounds or not. Thus, residues of
of nitroaromatic, nitramine, and nitrate ester explosives
RDX are present at much higher surface concentrations
in water using solid-phase extraction and GC-ECD:
than TNT. The presence of NG in range residues was
Comparison with HPLC. Journal of Chromatographic
unexpected and appears to be a general phenomenon
Science, 36: 406416.
based on analysis of these samples and samples
Yinon, J., and S. Zitrin (1993) Modern Methods and
collected at Canadian Force Base Valcartier, and to a
Applications in Analysis of Explosives. West Sussex,
lesser extent, at Fort Ord. HMX was also observed in
England: John Wiley and Sons.
12
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