&EPA
United States
Environmental Protection
Agency
Office of Research and
Development
Washington DC 20460
EPA/600-R-95/528
August 1995
Innovative Technology
Verification Report
Field Analytical Screening
Program: PCP Method
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UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
Office of Research and Development
Washington, DC 20460
Field Analytical Screening Program: PCP Method
Executive Summary
This innovative technology evaluation report (ITER) presents information on the demonstration of the
U. S . Environmental Protection Agency (EPA) Region 7 Superftmd Field Analytical Screening Program (FASP)
method for determining pentachlorophenol (PCP) contamination in soil and water. This method was
demonstrated in Morrisville, North Carolina, in August 1993. The demonstration was conducted by PRC
Environmental Management, Inc. (PRC), under contract to the EPA Environmental Monitoring Systems
Laboratory-Las Vegas (EMSL-LV). The demonstration was developed under the Monitoring and Measurement
Technologies Program (MMTP) of the Superfund innovative Technologies Evaluation (SITE) Program.
The FASP PCP Method was demonstrated in conjunction with the demonstrations of four other field
screening technologies: (1) the EINU-Hanby Test Kit developed by HNU Systems, (2) the Penta RISc Test
Systems developed by EnSys Incorporated, (3) the EnviroGard PCP Test Kit developed by Millipore
Corporation, and (4) the Penta RaPID Assays developed by Ohmicron Corporation. The results of these
demonstrations are presented in separate reports similar to this one.
The first objective of this demonstration was to evaluate the FASP PCP Method for accuracy and
precision in detecting high and low levels of PCP by comparing its results to those from a confirmatory
laboratory that used standard EPA-approved analytical methods. These EPA-approved methods are used to
provide legally defensible analytical data to monitor or enforce environmental regulations. Because these
EPAapproved methods are used by the regulatory community, this demonstration also used these methods. While
these methods may include inherent tendencies that may bias data or may include procedures that developers disagree
with, they are the best methods for providing legally defensible data as defined by the regulatory community.
To remove as much of these inherent tendencies as possible, PRC used post hoc residual analysis to remove
data outliers. The FASP PCP technology was also qualitatively evaluated for the length of time required for
analysis, ease of use, portability, and operating cost.
The second objective of the demonstration was to evaluate the specificity of the technology. The specificity
was evaluated by examining the effects of naturally-occurring matrix effects, site-specific matrix
effects, and chemical cross-reactivity. Information on the technology's specificity was gathered from literature, the
analysis of demonstration samples, and through a specificity study.
The site selected for demonstrating the technology was the former Koppers Company (Koppers) site in
Morrisville, North Carolina. This site was selected because a National Risk Management Research Laboratory
(NRMRL) SITE demonstration was planned for this site, allowing a conjunction of logistical and support efforts
between NRMRL and EMSL-LV. Another reason for selecting the former Koppers site was that historical
documentation indicated that PCP contamination ranged from none detected to 3,200 parts per million @pm) in soil
and from none detected to 1,490 parts per billion (ppb) in groundwater. The PCP carrier used at this site was a
mixture of isopropyl ether and butane. Soil and water samples also were collected from the Winona Post site in
Winona, Missouri. Samples from the Winona Post site were shipped to the former Koppers site for inclusion as
demonstration samples. Winona Post samples were included to broaden the scope of the demonstration by
introducing a different sample matrix and a different PCP carrier, diesel fuel.
The FASP PCP Method is designed to provide quick, accurate results for PCP concentrations in soil and water
samples. This method also can detect and quantify other phenols. PCP concentrations are reported in either parts
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per billion or parts per million for soils and parts per billion for waters. This method was developed by the
EPA Superfund Branch for use at Superfund sites.
The FASP PCP Method uses a gas chromatograph (GC) equipped with a megabore capillary column and
either a flame ionization detector (FID) or an electron capture detector (BCD) to identify and quantify PCP.
Gas chromatography is an EPA-approved method for determining PCP concentrations in soil, water, and
waste samples. The FASP PCP Method is an abbreviated, modified version of these methods.
Soil and water samples require extraction before GC analysis. To remove interferences caused by petroleum
hydrocarbons, including PCP carriers such as mineral spirits, kerosene, diesel fuel, and fuel oil, an acid-base
partition cleanup step. In this step, the method includes petroleum hydrocarbons are removed from the reagent
water, while potassium phenates remain in the reagent water. Sample extracts are injected onto a GC,
separated with a DB-5 megabore capillary column, and the PCP is identified and quantified using an FID. The
sample extracts are then compared to standards to determine whether PCP is present in the sample and, if
so, at what concentration. The FASP PCP Method will only provide high parts per billion detection levels of
PCP in water when an FID is used. To achieve a lower detection limit, the sample extracts are reanalyzed using
an BCD.
The FASP PCP method is field-portable only in a mobile laboratory. It should be used indoors in a
temperature-controlled environment. Reagents required for soil and water sample analysis require refrigeration
and the GC and extraction fume hood require electricity. The FASP PCP Method requires experienced GC
operators to produce reliable results. The average number of demonstration samples extracted,
concentrated, and analyzed in one lo-hour day during the demonstration was 14. The detection limit reported
by this method for soil samples is 0.8 ppm and 1 .O ppb for water samples.
The FASP PCP Method can be affected by naturally occurring matrix effects such as humic acids, pH, or
salinity. Other matrix effects include PCP carriers such as petroleum hydrocarbons or solvents. Due to the
nature of chromatography, this method is not greatly influenced by chemical cross-reactivity. The FASP PCP
Method was found to be most affected by the diesel fuel used as a PCP carrier solvent. A specificity study
performed during the demonstration showed that diesel fuel would provide a positive response when present at
a concentration of 10 ppm. Petroleum hydrocarbon interferences were found to affect results for the Winona
Post samples.
PRC used linear regression and inferential statistics to compare the technology's data to that from the
confirmatory laboratory. When the data sets were evaluated as a whole, a less accurate performance on the
Winona Post samples was observed due to the diesel fuel PCP carrier solvent. Both the entire data set and the
Winona Post data alone showed that the method produced Level 1 data. However, the method performed
well when the samples from the former Koppers site were examined separately. Within this data grouping,
the technology produced Level 2 data, which was statistically similar to that from the confirmatory
laboratory or that could be mathematically corrected to become similar to that from the confirmatory laboratory.
Generally, if 10 to 20 percent of the soil samples (not contaminated with petroleum) are sent to a confirmatory
laboratory, then the results from the other 80 to 90 percent can be corrected. This could result in a
significant savings in analytical costs. The water analysis portion of this demonstration produced similar
results. The FASP PCP Method produced Level 2 data for the samples collected from the former Koppers site.
The regression analysis and the Wilcoxon Signed Ranks Test indicated that the technology's data is strongly
correlated to the confirmatory data, but is statistically different. This means that the FASP PCP Method's data
must be mathematically corrected by having 10 to 20 percent of its samples slated for confirmatory
analysis. The Winona Post data showed that even when using sample cleanup, the method produces Level 1 data
that is both dissimilar to the confirmatory data and that cannot be mathematically corrected.
PRC evaluated field duplicate samples to determine the technology's precision relative to the confirmatory
laboratory's. PRC found no significant difference between the precision of the FASP PCP Method and that
of the confirmatory laboratory's for soil and water analysis. In addition, no PCP carrier effect on precision
was observed.
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