(CRREL) for Method 8330 and 8095 sample prepara-
ing the preliminary investigations, which had used
tion and analysis. All of the samples were taken near
Method 8330 for sample preparation and analysis. How-
buried mines after their exact location and orientation
ever, other explosives residues were believed to be
were established using a differential global positioning
present as well. At this site the GC-TID was set up in
system, a template, and four metal tent stakes. The
the command post trailer on a folding table and nitro-
majority of samples was obtained by removing the first
gen was used as the carrier gas. The calibration stan-
couple of millimeters of the ground's surface with a
dard prepared for this site contained 2,6-DNT, 2,4-DNT,
paint scraper after cutting away the vegetation with
TNB, TNT, RDX, 4AmDNT, 2AmDNT, tetryl, and
scissors. Because of the presence of vegetation (grass
HMX. The calibration standards used ranged from 5.0
and weed roots, etc.) these samples often contained a
to 40 mg/L for HMX, 0.5 to 40 mg/L for 2,6-DNT and
large amount of organic matter. In some cases the mine
RDX, and 0.25 to 20 mg/L for the other six analytes.
was removed (unearthed). The soil samples that were
The sampling plan for the OB/OD characterization
obtained during a mine excavation were collected just
activity called for a representative surface soil sample
to be taken from each 20- 20-ft subgrid in the region
above, below, and around the sides of the mine casing,
and consisted mainly of mineral soil and small pebbles.
of concern. To accomplish this task the subgrid was
For on-site analysis, 0.5 to 3 g of soil/organic matter
divided into quadrants, and surface soil samples ob-
was transferred to a pre-weighed 20-mL glass scintilla-
tained from each quadrant were composited. After thor-
tion vial, then returned to the on-site lab. After the vial
ough mixing, a sample was taken by filling a 4-oz glass
was re-weighed to obtain the sample's moist weight an
jar for subsequent on- or off-site (or both) analysis. All
equal or two-times-greater volume of hardware-
of the samples were stored in a refrigerator until pro-
store-grade acetone was added using either a 0.500-mL
cessed on site for analysis by Methods 8515 and 8510.
syringe or 5-mL graduated cylinder. The low-sample-
The first step for both of these on-site methods was to
weight-to-extraction-solvent volume and short extrac-
extract 20 g of soil with 100 mL of acetone in a plastic
tion period were used to optimize sensitivity and analy-
bottle. Following extraction an aliquot of the solvent
sis speed. A greater than 1:1 ratio of acetone to sample
was filtered. In addition to the filtered aliquot taken for
weight, however, was needed when a large amount of
Method 8510, a separate aliquot was transferred to a 2-
organic matter was present. Once the acetone was
mL amber deactivated glass vial and stored in a freezer
added, the vial was capped, manually shaken at least
for on-site GC-TID analysis. This additional aliquot of
twice for about 15 seconds, and then allowed to sit for
sample extract was obtained from about one quarter of
5 to 10 minutes. If organic matter was present, first a 3-
the 437 samples scheduled to be processed. The ana-
mL Luer-Lok syringe (Becton Dickinson & Co.) with
lytical team from Dames and Moore, on contract to the
its guard cap in place was used to depress this debris
Seattle District, Corps of Engineers, performed these
below the solvent layer. Then, to collect at least 0.5 mL
sample preparation steps. In addition to these samples,
of the supernatant, the cap on the tip of the syringe was
soil and sediment samples that have been archived on
removed and the syringe was pressed into the organic
site during other site characterization activities were
matter slurry. When only soil was present in the sample
made available for analysis, as were a couple of water
vial a clear solvent layer often formed, from which a
sample extracts (solid phase extraction [Walsh and
0.5-mL or larger aliquot was withdrawn. The filtered
Ranney 1998]) from a groundwater treatment plant.
sample extracts ranged in volume from 0.2 to 0.8 mL.
After analysis, all of the sample extracts were stored in
Following on-site analysis, the sample extracts (about
a freezer prior to shipment to CRREL. A subset of the
70) were stored on ice and returned to CRREL, where
sample extracts was re-analyzed by GC-ECD (Method
a subset of the extracts was re-analyzed by GC-ECD
8095) at CRREL within two weeks of sample collec-
(Method 8095) within two weeks of collection to evalu-
tion, to evaluate the on-site results.
ate the on-site results.
Environmental Technology Verification
Umatilla Chemical Depot
Program (ETV)
The Umatilla Chemical Depot in Hermiston, Oregon,
The Environmental Technology Verification Pro-
was visited on May 2426, 2000. One of the character-
gram (ETV) was established by the U.S. Environmen-
ization activities under way at this site was to identify
tal Protection Agency to provide a third-party perfor-
where high concentrations (mg/kg) of TNT and RDX
mance evaluation process for innovative or improved
remained near the surface in an area that had been used
environmental technologies (www.epa.gov/etv). The ul-
for the open burning and open detonation (OB/OD) of
timate objective of the ETV program is to expedite and
obsolete munitions. These two explosives had been
facilitate the recognition of cost-effective technologies
identified as principal contaminants of concern follow-
for use with environmental problems. This particular
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