application on the HM 2000 system, allowing for the
15 analyses) would have to be purchased for a visual
direct readout of the TPH concentration in a sample.
analysis, one Hanby Test Kit and one reagent supply
During this field exercise, the HM 2010 was only
kit (approximately 00, 30 analyses) would be nec-
capable of producing voltage responses, which had to
essary for analysis with the HM 2010, and one Hanby
be manually interpreted to generate sample TPH con-
Test Kit and six reagent supply kits (,000, 105 analy-
centrations. Samples were measured with the HM 2010
ses) would be necessary for analysis with the HM 2000.
about 5 minutes after the catalyst was added, and about
3 minutes later, the same cuvette was placed in the HM
EXPERIMENTAL DESIGN
2000. Samples can be prepared and analyzed by all three
methods within 15 minutes.
The reported detection limits for TPH in environ-
As mentioned earlier, these three methods of esti-
mental matrices for all three methods of analysis are
mating TPH concentrations on-site were evaluated with
about 10 mg/kg for soil samples and 0.1 mg/L for wa-
samples contaminated by petroleum products. Both soil
ter samples. With all of these measurement systems,
and groundwater matrices were evaluated for GRO and
the upper end of the calibration range is 1000 mg TPH/
DRO/bunker C, while RRO was only assessed in soil
kg for soil and 50 mg TPH/L for water. Samples that
samples (Table 1). All of the participants helped
exceeded these ranges were reanalyzed by diluting a
develop the sampling plan for this field exercise. This
small quantity of the sample extract. The technology
was necessary to ensure that the number and type of
developer claims that, by following the recommended
samples anticipated could be processed in the time
sample preparation and analytical procedures, TPH
allotted, and so that the sample integrity would not be
concentration estimated with these three methods are
compromised. This second requirement means that the
within 25% or better of the values established by stan-
samples are representative of the in-situ conditions.
dard laboratory methods (Hanby 1998).
More importantly, it attempts to eliminate potential
Independent of which method of analysis is used,
sources of determinant error, with respect to the han-
the cost of purchasing the matrix-appropriate Hanby
dling and distribution of samples, so that the different
Test Kit, for performing the Friedel-Crafts alkylation
methods of preparing and estimating TPH concentra-
reaction, is approximately 00. It comes with enough
tions can be validly compared.
reagents for 15 samples, and includes photographic
The protocol developed used a single and double
charts for a visual analysis. Reagent supply kits for an
blind format for both the technology developer and the
additional 15 samples can be purchased for 0. The
reference laboratory. Therefore, aside from knowing the
HM 2010 and HM 2000 are currently projected to sell
range of hydrocarbons representative of contamination
for about 0 and approximately 00 (laptop com-
present in a given sample (i.e., GRO range) and matrix
puter included), respectively. To bring the cost per
(i.e., soil or groundwater) it was often impossible to
sample analyzed below 0, the approximate cost of
distinguish a field sample from a matrix spike, matrix
a TPH laboratory analysis, one Hanby Test Kit (00,
blank, or a PE sample. This was accomplished on-site
Table 1. Samples collected and prepared for on-site analysis.
Field
Matrix
Samples
Duplicate
Blank
Spike duplicate
PE*
Total
Gasoline range organics (GRO; b.p. 60170C)
Soil
9
2
1
2 (4)†
4
20
Water
6
1
1
2 (4)
4
16
Diesel range organics (DRO; b.p. 160400C)
Soil
12
2
1
2 (4)
8
27
Water
12
1
1
2 (4)
--
18
Residual (motor oil) range organics (RRO; b.p. 315540C)
Soil
6
1
--
1 (2)
--
9
*Performance evaluation samples.
†Number in parenthesis are the total number of matrix spike samples.
3
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