Table 5. Concentration estimates (mg/L) of
Table 6. Average concentration estimates (mg/
total petroleum hydrocarbons (TPH) for per-
kg) and standard deviations of total petroleum
formance evaluation diesel in water stan-
hydrocarbons (TPH) for laboratory soil samples
dards analyzed during laboratory trials.
spiked with gasoline.
Catalog /
Certified
Soil type and
lot numbers
concentration
Visual
HM 2000
target value
CRREL
Visual
HM 2000
764/50022*
0.903
1.5
3.6
Silt
1005
782
764/50022
0.903
1.5
3.5
100 mg TPH/kg*
50
764/50022
0.903
1.5
3.6
(100%)†
(50%)
(78%)
764/50022
0.903
1.5
3.6
[5%]**
[2.6%]
3.60.05**
1.5
55013
44052
520 mg TPH/kg*
200
(170%)†
(400%)
(106%)
(38%)
(85%)
[1.4%]††
[2%]
[12%]
Clay
764/50022‡
0.360
1.0
2.2
1001
869
100 mg TPH/kg*
50
764/50022
0.360
1.0
2.1
(100%)
(50%)
(86%)
764/50022
0.360
0.5
0.6
[1%]
[10%]
764/50022
0.360
0.5
0.4
54015
48074
520 mg TPH/kg*
200
764/50022
0.360
1.0
1.8
(104%)
(38%)
(92%)
764/50022
0.360
1.0
2.1
[3%]
[15%]
764/50022
0.360
1.0
2.2
1.60.78
Silt/Clay/Sand
0.86
1901
16010
200 mg TPH/kg*
150
(240%)
(440%)
(95%)
(75%)
(80%)
[49%]
[1%]
[6%]
* Concentrated QA standard diluted 1.0 mL to 1.00 L.
1000 mg TPH/kg* 110050
>500
>1000
†
Percent recovery relative to the certified concen-
(110%)
tration.
[5%]
** Average and standard deviation.
Silt
†† Percent relative standard deviation.
2004
1309
200 mg TPH/kg*
150
‡ Concentrated QA standard diluted 1.0 mL to 2.50 L.
(100%)
(75%)
(65%)
[2%]
[7%]
110015
1000 mg TPH/kg*
>500
>1000
The results for the PE soil samples (Table 4) show
(110%)
that HM 2000 tended to overestimate the amount of
[1%]
TPH present (three out of four cases), and in only one
Silt/Clay/Sand
20 mg TPH/kg†† 210.5
195.8
case was it capable of yielding an average value that fell
110
(105%)
(95%)
within the performance acceptance limits (Table 1). The
[2%]
[31%]
HM 2000 had the same problems with the PE water
samples (Table 5). The visual method of analysis and a
* n = 3.
†
Percent recovery relative to target value.
reference method (for gasoline) consistently yielded
** Percent relative standard deviation.
TPH concentration estimates that were within the per-
†† n = 7.
formance acceptance limits for the PE soil samples
(Table 1). For the PE water samples, however, the visual
centrations for the soil and water matrices contaminat-
method also gave TPH values that were above of the
ed with gasoline (Tables 8 and 10) that were with 21%
acceptance limits, but they were not as aberrant as the
and, frequently (12 out of 16), within 10% of the tar-
HM 2000 estimates.
get value.
The results obtained with the HM 2000 for labora-
The percent relative standard deviations (%RSD) for
tory soils spiked with gasoline and diesel fuel were often
the HM 2000 measurements were below 25% for all
in good agreement with the target concentrations (Tables
but one of the PE soil and water samples (Tables 4 and
6 and 7). In 10 out of 13 cases, the estimates with the
HM 2000 were within 22% of the target concentra-
5). The PE sample that showed a %RSD greater than
25% had a concentration near the reported detection
tion, and often were closer to the target value than the
limit (Table 5). With two exceptions, the %RSDs for
visual method. The opposite trend was seen for the lab-
the HM 2000 values were below 35% for the triplicate
oratory spiked water samples (Table 8), where the HM
soil matrix spikes (Tables 6 and 7). The %RSDs estab-
2000 estimates ranged from a false negative to an over-
lished by the reference method for the PE and spiked
estimation of the target TPH concentration by factor of
three. The visual estimates were within 50% of the
soil and water samples were 10% or less. Because the
visual estimates arise from a discontinuous scale and
target values. The reference method provided TPH con-
6
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