dards using peak heights. Detection limits for 4A2NT,
At the contract laboratory, the samples were also ana-
2A4NT, and 3,5-DNA were about 250 g/kg.
lyzed by RP-HPLC according to SW-846 Method 8330
(EPA 1994).
Analysis of fragments from low-order
Laboratory analyses for geochemical parameters
hand grenade detonation
included total iron, calcium, magnesium, and manga-
A hand grenade casing that had undergone a low-
nese (Method 6010, U.S. EPA 1988), total organic car-
order detonation was discovered at the Fort Lewis hand
bon (Method 505C, American Public Health Associa-
grenade range and was sent back to CRREL for analy-
tion 1985), nitrate/nitrite nitrogen (Method 353.2, U.S.
sis. Visually it appeared that residual Composition B,
EPA 1982), sulfate (Method 375.2, U.S. EPA 1982),
the main charge for M67 grenades, was still present on
and chloride (Method 325.2, U.S. EPA 1979). Samples
the surface of this metal casing. Small portions of the
for total iron, calcium, magnesium, and manganese,
hand grenade casing were placed in 5.0 mL of acetone
total organic carbon, and nitrate/nitrite nitrogen were
and allowed to dissolve for five minutes, at which time
preserved with 0.4 g NaHSO4 to 250 mL of water. Sam-
an aliquot of the acetone extract was removed for analy-
ples for sulfate and chloride were not preserved. Iron
sis. After an additional 15 minutes of soaking, a second
speciation was achieved by ion chromatographic sepa-
aliquot was removed for analysis. Both acetone extracts
ration (Dionex Corp., Sunnyvale, California) of sam-
were diluted 1:100 with acetone and the diluted extract
ples preserved with 1 percent HCl followed by analy-
was further diluted 1 to 3 parts water. The resulting
sis according to Method 6020, (U.S. EPA 1988) on a
solutions were analyzed using the separations described
Perkin Elmer (Norwalk, Connecticut) inductively cou-
in SW-846 Method 8330 (EPA 1994).
pled plasma mass spectrometer.
Analysis of water samples from
Historical firing records
monitoring wells and seeps at Fort Lewis
Historical firing records contained in an electronic
At CRREL, the water samples were extracted using
database at Fort Lewis were reviewed to understand
solid-phase extraction as described in SW-846 Method
the major components potentially contributing to an
3535A (draft) (EPA 2000c). Specifically, 500 mL of
explosives contamination source term on the heavy artil-
each sample was passed through a 500-mg Sep-Pak
lery impact range. These records were available from
Porapak RDX cartridge (Waters) and the retained ana-
1997 through the time of sampling, July 2000. Only
lytes were eluted using 5.0 mL of acetonitrile. The
munitions items identified by the Fort Lewis Range
extracts were analyzed by GC-ECD as described above
Operations Office as "high use" were included. These
for soil extract analysis.
were 81-, 120-, and 107-mm mortars and 105-and 155-
At ERDC-EL, the water samples were also extract-
mm howitzers. The database provided the number of
ed using solid-phase extraction as described above.
rounds by Department of Defense Identification Code
Analyses were conducted by RP-HLPC-UV according
(DODIC) number, date, and location where firing was
to SW-846 Method 8330 (EPA 1994) on a Waters sys-
scheduled to occur. Composition of these rounds was
tem composed of a Waters 610 Fluid Unit pump, a
determined by consulting the Munitions Items Dispo-
Waters 717 plus autosampler with a 200-l loop injec-
sition Action System (MIDAS) and Mark Serben, Office
tor, a Waters 486 Tunable UV Absorbance detector
of the Product Manager for Mortar Systems, TACOM,
monitored at 245 nm, and Millennium 2.1 Chromatog-
Picatinny Arsenal, New Jersey. The dud and low-order
raphy Software (Waters Chromatography Division,
detonation rates for these munitions were extracted from
Milford, Massachusetts). Separations were obtained on
the data generated by the U.S. Army Defense Ammu-
Supelco LC-18 reverse-phase HPLC column 25 cm
nition Center, McAlester, Oklahoma (Dauphin and
4.6 mm (5 m) with second column confirmation on a
Doyle 2000).
Supelco LC-CN reverse phase column (25 cm 4.6
mm, 5 m). Additional transformation products of TNT
RESULTS AND DISCUSSION
and TNB assayed by the ERDC-EL laboratory includ-
Hand grenade ranges, Fort Lewis and
ed 3,5-dinitroaniline (DNA), 2,4-diamino-6-nitrotolu-
Fort Richardson
ene (2,4DANT), and 2,6-diamino-4-nitrotoluene
(2,6DANT) and 2,2,6,6-tetranitro-4,4-azoxytoluene
The results from the analysis of the soil samples
(44AZOXY). Additional transformation products of
collected from the Fort Lewis hand grenade range are
RDX assayed by the ERDC-EL laboratory included
presented in Table 4. Of the 19 target analytes of the
hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine (MNX),
method, RDX, TNT, HMX, 2,4-DNT, 2-ADNT, 4-
hexahydro, 1,3,5-trinitroso-1,3,5-triazine (TNX), and
ADNT, 1,3,5-TNB, 2,6-DNT, and 3,5-DNA were found
at concentrations exceeding 10 g/kg (10 parts per bil-
hexahydo-1,3-dinitroso-5-nitro-1,3,5-triazine (DNX).
10
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