&EPA
United States
Environmental Protection
Agency
Office of Research and
Development
Washington DC 20460
EPA/540/R-95/528
August 1995
Field Analytical Screening
Program: POP Method
Innovative Technology
Evaluation Report
SUPERFUND INNOVATIVE
TECHNOLOGY EVALUATION
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EPA/540/R-95/528
August 1995
FIELD ANALYTICAL SCREENING PROGRAM: PCP
METHOD
INNOVATIVE TECHNOLOGY EVALUATION REPORT
NATIONAL RISK MANAGEMENT RESEARCH LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
CINCINNATI, OHIO 45268
NATIONAL EXPOSURE RESEARCH LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
LAS VEGAS, NEVADA 89193
Printed on Recycled Paper
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Notice
The information in this document has been funded wholly or in part by the U.S. Environmental
Protection Agency (EPA) in partial fulfillment of Contract No. 68-CO-0047, Work Assignment
No. 0-40, to PRC Environmental Management, Inc. It has been subject to the Agency's peer and
administrative review, and it has been approved for publication as an EPA document. The
opinions, findings, and conclusions expressed herein are those of the contractor and not
necessarily those of the EPA or other cooperating agencies. Mention of company or product
names is not to be construed as an endorsement by the agency.
11
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Foreword
The U.S. Environmental Protection Agency is charged by Congress with protecting the Nation's land,
air, and water resources. Under a mandate of national environmental laws, the Agency strives to formulate and
implement actions leading to a compatible balance between human activities and the ability of natural systems
to support and nurture life. To meet this mandate, EPA's research program is providing data and technical
support for solving environmental problems today and building a science knowledge base necessary to manage
our ecological resources wisely, understand how pollutants affect our health, and prevent or reduce environmental
risks in the future.
The National Risk Management Research Laboratory is the Agency's center for investigation of
technological and management approaches for reducing risks from threats to human health and the environment.
The focus of the Laboratory's research program is on methods for the prevention and control of pollution to air,
land, water and subsurface resources; protection of water quality in public water systems ; remediation of
contaminated sites and ground water; and prevention and control of indoor air pollution. The goal of this research
effort is to catalyze development and implementation of innovative, cost-effective environmental technologies;
develop scientific and engineering information needed by EPA to support regulatory and policy decisions; and
provide technical support and information transfer to ensure effective implementation of environmental
regulations and strategies.
This publication has been produced as part of the Laboratory's strategic long-term research plan. It is
published and made available by EPA's Office of Research and Development to assist the user community and
to link researchers with their clients.
E. Timothy Oppelt, Director
National Risk Management Research Laboratory
111
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Abstract
This innovative technology evaluation report (ITER) presents information on the demonstration of the U.S.
Environmental Protection Agency (EPA) Region 7 Superfund 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 FASP PCP Method was developed by the EPA Superfund Branch for use at Superfund sites. The method uses
a gas chromatograph (GC) equipped with a megabore capillary column and either a flame ionization detector (FID)
or an electron capture detector (ECD). 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
approved methods. Soil and water samples require extraction before GC analysis. To remove interferences caused
by petroleum hydrocarbons, an acid-base partition cleanup step is used during the FASP PCP Method.
The FASP PCP Method was found to be field-portable only in a mobile laboratory, must be done in a temperature-
controlled environment, and requires a skilled chemist for operation. The detection limit reported by this method for
is 0.8 part per million for soil samples and 1.0 part per billion for water samples. PRC used linear regression and
inferential statistics to compare the method's data to that from the confirmatory laboratory. When the data sets were
evaluated as a whole, the FASP PCP Method did not perform well. However, the demonstration's samples were
collected from two different sites, and the method was found to have performed well on samples from the site where
petroleum hydrocarbons had not been used as a carrier solvent. This indicates that the problems with the method may
have been due to the petroleum hydrocarbons in the soil. The water analysis portion of this demonstration produced
similar results.
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.
This report was submitted in partial fulfilment of contract 68-CO-0047 by PRC Environmental Management, Inc.,
under the sponsorship of the U.S. Environmental Protection Agency. This report covers a period from July 1, 1993,
to August 31, 1993, and work was completed as of February 1, 1994.
IV
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Table of Contents
Section Page
Notice ii
Foreword iii
Abstract iv
List of Figures vii
List of Tables : vii
List of Abbreviations and Acronyms viii
Acknowledgments ix
1 Executive Summary '. 1
2 Introduction 3
EPA's Site Program and MMTP: an Overview 3
The Role of Monitoring and Measurement Technologies 3
Defining the Process 4
Components of a Demonstration 4
Rationale for this Demonstration 4
Demonstration Purpose, Goals, and Objectives 5
3 Predemonstration Activities 6
Identifying Developers 6
The Sites and Their Principal Contaminants 6
Selecting the Confirmatory Laboratory and Analytical Methods 7
Training Technology Operators 7
Predemonstration Sampling and Analysis 7
4 Demonstration Design and Description 8
Demonstration Design 8
Implementation of the Demonstration Plan 8
Field Modifications to the Demonstration Plan 9
Data Collection 9
Statistical Analysis of Results 10
5 Confirmatory Analysis Results 12
Confirmatory Laboratory Procedures 12
Sample Holding Times 12
Sample Extraction 12
Detection Limits and Initial and Continuing Calibrations 13
Sample Analysis 13
Quality Control Procedures 13
Data Reporting 14
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Table of Contents (Continued)
Section Page
Data Quality Assessment 15
Confirmatory Laboratory Costs and Turnaround Times 16
6 EPA Region 7 Superfund Program: FASP PCP Method 17
Operational Characteristics 17
Performance Factors 20
Specificity 21
Intramethod Assessment 22
Comparison of Results to Confirmatory Laboratory Results 26
Soil Samples: Intermethod Accuracy 26
Soil Samples: Intermethod Precision 31
Water Samples: Intermethod Accuracy 31
Water Samples: Intermethod Precision 32
7 Applications Assessment 33
8 References 35
VI
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List of Figures
Figure Page
6-1 FASP PCP Method vs. Confirmatory Analysis: Total Soil Data Set 26
6-2 FASP PCP Method vs. Confirmatory Analysis: Former Koppers Site Soil Samples 27
6-3 FASP PCP Method vs. Confirmatory Analysis: Winona Post Soil Samples 27
6-4 FASP PCP Method vs. Confirmatory Analysis: Total Water Data Set 31
6-5 FASP PCP Method vs. Confirmatory Analysis: Former Koppers Site Water Samples 32
6-6 FASP PCP Method vs. Confirmatory Analysis: Winona Post Water Samples 32
List of Tables
Table Page
5-1 Soil Matrix Spike Sample Results for EPA Methods 8270A and 8151A 15
5-2 Water Matrix Spike Sample Results for EPA Methods 8270A and 515.1 15
6-1 Soil Matrix Spike Sample Results for the FASP PCP Method 24
6-2 Water Matrix Spike Sample Results for the FASP PCP Method 24
6-3 Soil Laboratory Duplicate Sample Results for the FASP PCP Method 25
6-4 Water Laboratory Duplicate Sample Results for the FASP PCP Method 25
6-5 Soil Field Duplicate Sample Results for the FASP PCP Method 25
6-6 Water Field Duplicate Sample Results for the FASP PCP Method 25
6-7 Summary of Demonstration Data: Former Koppers Site Soil Samples 28
6-8 Summary of Demonstration Data: Winona Post Soil Samples 29
6-9 Summary of Demonstration Water Data 30
6-10 Summary of Regression and Residual Statistics Soil Accuracy 30
VII
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List of Abbreviations and Acronyms
Beazer Beazer East, Inc.
CCAL continuing calibration
DCAA 2,4-dichlorophenylacetic acid
ECD electron capture detector
EMSL-LV Environmental Monitoring Systems Laboratory-Las Vegas
EPA Environmental Protection Agency
ERA Environmental Resource Associates
ESAT Environmental Services Assistance Team
FASP Field Analytical Screening Program
FID flame ionization detector
GC gas chromatograph
ICAL initial calibration
IDW investigation-derived waste
ITER Innovative Technology Evaluation Report
Koppers Koppers Company
,wg/kg micrograms per kilogram
,ug/L microgram per liter
mg/kg milligram per kilogram
MMTP Monitoring and Measurement Technologies Program
MtBE methyl tert-butyl ether
NRMRL National Risk Management Research Laboratory
ORD Office of Research and Development
OSWER Office of Solid Waste and Emergency Response
PCP pentachlorophenol
PE performance evaluation
ppb parts per billion
ppm parts per million
PRC PRC Environmental Management, Inc.
QA quality assurance
QADE quality assurance and data evaluation
QAPP Quality Assurance Project Plan
QC quality control
RCRA Resource Conservation and Recovery Act
RECAP Region 7 Environmental Collection and Analysis Program
RPD relative percent difference
RSD relative standard deviation
SARA Superfund Amendments and Reauthorization Act of 1986
SITE Superfund Innovative Technology Evaluation
SMO Sample Management Office
SVOC semivolatile organic compounds
USI Unit Structures, Inc.
VIII
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Acknowledgments
This demonstration and the subsequent preparation of this report required the services and support of numerous
personnel from the EPA Environmental Monitoring Systems Laboratory (Las Vegas, Nevada); EPA Region 7 (Kansas
City, Kansas); Beazer East, Inc. (Pittsburgh, Pennsylvania); Winona Post, Inc. (Winona, Missouri); and PRC
Environmental Management, Inc. (Kansas City, Kansas; Cincinnati, Ohio; and Chicago, Illinois). The cooperation
and efforts of these organizations and personnel are gratefully acknowledged.
Additional information concerning the demonstration and technology described in this report can be obtained by
contacting Mr. Lary Jack, EPA Environmental Monitoring Systems Laboratory, technical project manager, at (702)
798-2373, or Mr. Eric Hess, PRC Environmental Management, Inc., project manager, at (913) 573-1822.
IX
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Section 1
Executive Summary
This innovative technology evaluation report (ITER)
presents information on the demonstration of the
U.S. Environmental Protection Agency (EPA) Region 7
Superfund 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
LaboratoryLas Vegas (EMSL-LV). The demon-stration
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 HNU-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 EPA-
approved 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 (ppm) 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
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.
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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-S 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
anECD.
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 10-hour day during
the demonstration was 14. The detection limit reported
by this method for soil samples is 0.8 ppm and 1.0 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 die results from die oflier 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 die 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 bom dissimilar to the confirmatory data and that
cannot be mathematically corrected.
PRC evaluated field duplicate samples to determine
the technology's precision relative to me 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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Section 2
Introduction
This ITER presents information on the demonstration
of the FASP method designed to detect PCP in soil and
water. PRC conducted the demonstration under the EPA
SITE Program. The FASP technology was demonstrated
in conjunction with the demonstrations of four other
technologies: (1) the Penta RISc Test System developed by
EnSys Incorporated, (2) the EnviroGard PCP Test Kit
developed by Millipore Corporation, (3) the Penta RaPID
Assay developed by Ohmicron Corporation, and (4) the
HNU-Hanby Test Kit developed by HNU Systems. The
results of these other technologies are presented in
separate reports similar to this one. All tables and figures
referenced in this document are presented at the end of
their respective sections.
EPA Site Program and MMTP: An Overview
At the time of the Superfund Amendments and
Reauthorization Act of 1986 (SARA), it was well
recognized that the environmental cleanup problem needed
new and better methods. As a result, the SITE Program
was created to fulfill a requirement of SARA that EPA
address the potential of alternative or innovative
technologies. EPA made this program a joint effort
between the Office of Solid Waste and Emergency
Response (OSWER) and the Office of Research and
Development (ORD). The SITE Program includes four
parts:
The Demonstration Program (for remediation
technologies)
The Emerging Technology Program
The Monitoring and Measurement Technologies
Program (MMTP)
The Technology Transfer Program
The largest part of the SITE Program is concerned
with treatment technologies and is administered by ORD's
NRMRL in Cincinnati, Ohio. However, the MMTP
component is administered by EMSL-LV. The
MMTP is concerned with monitoring and measurement
technologies that identify, quantify, or monitor changes in
contaminants occurring at hazardous waste sites or that are
used to characterize a site.
The MMTP seeks to identify and demonstrate
innovative technologies that may provide less expensive,
better, faster, or safer means of completing this monitoring
or characterization. Managers of hazardous waste sites
are often reluctant to use any method, other than
conventional ones, to generate critical data on the nature
and extent of contamination. In addition, the courts
generally recognize data generated by conventional
laboratory methods; nevertheless, there is a tremendous
need to generate data more cost- effectively. Therefore,
me EPA must identify innovative approaches, and through
verifiable testing of the technologies under the SITE
Program, insure that the innovative technologies are
equivalent to or better than conventional technologies.
The Role of Monitoring and Measurement
Technologies
Measurement and monitoring technologies are needed
to assess the degree of contamination, to determine the
effects of contamination on public health and the
environment, to supply data for selection of appropriate
remedial action, and to monitor the success or failure of
selected remedies. Thus, the MMTP is concerned with
evaluating screening technologies, including remote
sensing, monitoring, and analytical technologies.
Candidate technologies may come from within the
federal government or from the private sector. Through
the program, developers are allowed to rigorously evaluate
the performance of their technologies. By distributing the
results and recommendations of those evaluations, the
market for the technologies is enhanced.
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Defining the Process
The demonstration process begins by canvasing the
EPA 10 regional offices (with input by OSWER and
ORD) to determine their needs. Concurrently, classes
of technologies are identified. An ideal match is made
when there is a clear need by EPA regions and a number
of technologies that can address that need.
Demonstrations are designed to judge each technology
against existing standards and not "one against the
other."
A demonstration is designed to provide for detailed
quality assurance and quality control (QA/QC) to insure
that a potential user can evaluate the accuracy, precision,
representativeness, completeness, and comparability of
data derived from the innovative technology. In
addition, a description of the necessary steps and
activities associated with operating the innovative
technology is prepared. Cost data, critical to any
environmental activity, are generated during the
demonstration to allow a potential user to make
economic comparisons. Finally, information on
practical matters such as operator training requirements,
detection levels, and ease of operation are reported.
Thus, the demonstration report and other informational
materials produced by the MMTP provide a real-world
comparison of the demonstrated technology to
conventional technologies. With cost and performance
data, as well as "how to" information, users can
determine whether a new technology better meets their
needs.
Components of a Demonstration
Once a decision has been made to demonstrate
technologies to meet a particular EPA need, the MMTP
performs a number of activities. First, MMTP identifies
potential participants and determines whether they are
interested in participating. Each developer is advised of
the general nature of the demonstration and is provided
with information common to all MMTP demonstrations.
Information is sought from each developer about its
technology to insure that the technology meets the
parameters of the demonstration. After evaluating the
information, MMTP informs all respondents whether or
not they have been accepted into the demonstration.
While participants are being identified, potential sites
also are identified, and basic site information is obtained.
The next component, probably the most important,
is the development of plans that describe how the
demonstration will be conducted. A major part of the
EPA's responsibility is to develop a demonstration plan,
a quality assurance project plan (QAPP), and a health
and safety plan. While the EPA pays for and has the
primary responsibility for these plans, each is developed
with input from all of the demonstration's participants.
The plans define how activities will be conducted and
how the technologies will be evaluated. MMTP also
provides each developer with site information and often
provides predemonstration samples so the developer can
maximize the field performance of its innovative
technology. Generally, the developers tram EPA-
designated personnel to operate the technologies so that
performance is not based on the special expertise of the
developers. This approach also insures that potential
users have valid information on training requirements
and the types of operators who typically use a technology
successfully.
The field demonstration itself is the shortest part of
the process. During the field demonstration, data is
obtained on cost, technical effectiveness (compared to
standard methods), and limiting factors. In addition,
standardized field methods are developed, and daily logs
of activities and observations (including photographs or
videotapes) are produced. EPA is also responsible for
the comparative, conventional method analytical costs
and the disposal of any wastes generated by the field
demonstration.
The final component of an MMTP demonstration
consists of reporting the results and insuring distribution
of demonstration information. The primary product of
the demonstration is an ITER, like this one, which is
peer-reviewed and distributed as part of the technology
transfer responsibility of the MMTP. The ITER fully
documents the procedures used during the field
demonstration, QA/QC results, the field demonstration's
results, and its conclusions. A separate QA/QC data
package is also made available for those interested hi
evaluating the demonstration hi greater depth. Two-page
"Technical Briefs" are prepared to summarize the
demonstration results and to insure rapid and wide
distribution of the information.
Each developer is responsible for providing the
equipment or technology product to be demonstrated, its
own mobilization costs, and the training of EPA-
designated operators. The MMTP does not provide any
funds to developers for costs associated with preparation
of equipment for demonstration or for development, and
it does not cover the costs developers incur to
demonstrate their products.
Rationale for this Demonstration
PCP is a regulated chemical, is included hi the EPA
Extremely Hazardous Substances List, and is reported hi
the EPA Toxic Substances Control Act. Recently, PCP
regulations under the Resource Conservation and
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Recovery Act (RCRA) have been created specifically for
wood treatment facilities. PCP is included as a target
compound of many EPA-approved analytical methods
including: EPA 500 Series Methods 515.1 and 525,
EPA 600 Series Methods 604 and 625, and
EPA SW-846 Manual Methods 8040, 8151, 8250, and
8270. All these methods use solvent extraction and gas
chromatography. Detection and quantitation is
performed with FIDs, ECPs, or mass spectrometer
detectors. Analyzing samples for PCP using these
methods is typically costly and time consuming.
EMSL-LV identified the need for effective, accurate,
low cost screening technologies that could provide near
real-time analytical data for PCP to Superfund and
RCRA decisionmakers.
Demonstration Purpose, Goals,
and Objectives
The FASP PCP Method was evaluated on its
accuracy and precision in detecting high and low levels
of PCP in environmental samples, and on the effects, if
any, of both PCP carrier and natural matrix
interferences. The accuracy and precision of the method
was statistically compared to the accuracy and precision
of a conventional confirmatory laboratory that used
EPA-approved analytical methods. This comparison was
also used to determine the highest data quality level that
the technology could attain in field applications. For the
purpose of this demonstration, three primary data quality
levels were defined as follows (EPA 1990):
Level 1: Level 1 data is not necessarily analyte-
specific. Technologies that generate
Level 1 data provide only an
indication of contamination. General-
ly, the use of these technologies
requires sample documentation, instru-
ment calibration, and performance
checks of equipment.
Level 2: Level 2 data is analyte-specific. To
provide an accuracy check, verifi-
cation analysis by an EPA-approved
method is necessary for at least
10 percent of the samples. The
method's analytical error is also
quantified. Use of QC procedures such
as sample documentation, chain-of-
custody procedures, sample holding
time criteria, initial and continuing
instrument calibration, method blank
analysis, rinsate blank analysis, and
trip blank analysis is recommended.
Level 3: Level 3 data is considered formal or
confirmatory analysis. These data are
analyte-specific and generally involve
second-method confirmation on
100 percent of critical samples.
Analytical error is quantified (in-
cluding precision, accuracy, and
coefficient of variation) and moni-
tored. The following QC measures are
used: sample documentation, chain of
custody, sample holding time criteria,
initial and continuing instrument
calibration, rinsate blank analysis, trip
blank analysis, and performance
evaluation samples. Detection limits
are determined and monitored.
Inherent in this concept of data quality levels is
accuracy. Although PRC could not find a reference that
defined the expected and quantified accuracy of each
data quality level, it imposed common accuracy criteria
in defining these data quality levels. Data quality Level
3 is considered the most accurate and is based on a
formal analysis by approved methods. Data quality
Level 2 is less accurate, but it still does quantify
compound concentrations. Data quality Level 1 is the
least accurate and is often considered survey data, useful
only in identifying the presence or absence of a
compound or class of compounds. Because no existing
quantification of the criteria defining these data quality
levels was found, PRC set the criteria used in this ITER
based on the experience of the EPA and PRC personnel
involved and on a general survey of environmental
consultants who use data.
The FASP PCP Method was also qualitatively
evaluated for specificity, the length of time required for
its analysis, ease of use, portability, and operating cost.
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Section 3
Predemonstration Activities
Several activities were conducted by EMSL-LV,
PRC, and other demonstration participants before the
demonstration began. These activities included identifying
developers, selecting demonstration sites, selecting the
confirmatory laboratory and analytical methods,
conducting predemonstration sampling, and training
technology operators. Predemonstration sampling and
analysis are normally used to allow developers to refine
their technologies and revise their operating instructions,
if necessary, prior to the demonstration.
Identifying Developers
EMSL-LV asked that PRC search for technologies
that could be included in this demonstration. Based on
PRC's search, the FASP method was included.
The Sites and Their Principal Contaminants
To evaluate the field screening technology under field
conditions, hazardous waste sites suitable for the
demonstration were needed. The following criteria were
used to select appropriate sites:
The technology needed to be demonstrated at
sites with a wide range of PCP contamination.
PCP concentrations at the sites had to be well
characterized and documented.
The sites had to be accessible for conducting
demonstration activities without interfering with
other activities being conducted on site.
Because various carriers have been used with
PCP and because those carriers may influence
the technology, it was determined that the sites
used should offer two different carriers.
The former Koppers wood treatment site was selected
as one of the two sites for this demonstration based on
these criteria. This site also was selected because EPA's
NRMRL was planning a SITE demonstration of the ETG
Environmental, Inc., Base-Catalyzed Decomposition
technology at the site, and choosing the former Koppers
site would allow for a conjunction of logistical and support
efforts between NRMRL and EMSL-LV. The second
demonstration site selected was the Winona Post site wood
treatment facility. The Winona Post site is contaminated
with PCP in a diesel fuel carrier solvent. The former
Koppers site is contaminated with PCP in butane and
isopropyl ether carrier solvents.
The former Koppers site is located in Morrisville,
North Carolina, at the intersection of Highway 54 and
Koppers Road. The site is currently owned by two
companies: Beazer East, Inc. (Beazer), and Unit
Structures, Inc. (USI). The portion of the site owned by
Beazer is inactive. The portion of the site owned by USI
is currently used as a wood laminating facility. The site
occupies about 52 acres and includes the wood laminating
building, an office, and several warehouses. Surrounding
land use is a mixture of commercial, light industrial, and
rural residential. During previous investigations at the
former Koppers facility, samples were collected from the
following media: soil, groundwater, surface water,
sediment, and fish. Sampling revealed PCP concentrations
ranging from not detected to 3,200 ppm in soils and from
not detected to 1,490 ppb in water.
The Winona Post site is located in Winona, Missouri,
on Old Highway 60 West. It has operated as a sawmilling
and wood preserving facility since at least the early 1950s.
The sawmilling, wood preserving, and storage areas of the
facility cover about 4 acres. The remaining portion of the
40-acre facility is wooded and largely undeveloped. The
main features of the facility include a sawmill, office,
treatment building, debarker, storage building, and pond.
Currently, the company uses a premixed solution of
5 percent PCP hi diesel fuel. The solution is stored in a
20,000-gallon aboveground storage tank located adjacent
to the treatment building. In the past, the Winona Post
Company mixed its own solution from concentrated PCP.
Prior to the mid-1950s, the Winona Post Company treated
wood with cresol. In 1992, six samples collected at the
Winona Post site revealed PCP concentrations ranging
from 886 to 24,000 ppm hi soil and sediment samples and
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from 10 to 528 ppm in surface water samples.
PCP is an organic chemical with an empirical formula
of C6C15OH and a molecular weight of
266 grams per mole. PCP has a melting point of 191 °C
and a boiling point of 310 °C. The specific gravity of
PCP is 1.978 grams per cubic centimeter. PCP is
described as almost insoluble in water, with 8 milligrams
able to dissolve into 100 milliliters of water. The octanol
ratio coefficient of PCP is 6,400, which indicates that PCP
is tightly bound to the soil matrix when it is released into
the environment. PCP is used as a wood preservative, an
insecticide, a preharvest defoliant, a slimicide, and a
defoaming agent. The largest user of PCP is the wood
treating industry. For treating wood, PCP is usually
diluted to a 5 percent solution with solvents such as
mineral spirits, kerosene, diesel fuel, or fuel oil. PCP
also has been applied to wood with methylene chloride and
liquified petroleum gas, such as butane. It has been
manufactured under numerous trade names.
Selecting the Confirmatory Laboratory and
Analytical Methods
Before this demonstration, the EPA Region 7
Laboratory arranged for all soil samples to be analyzed
under the Region 7 Environmental Collection and Analysis
Program (RECAP) Contract and all water samples to be
analyzed under its Environmental Services Assistance
Team (ESAT) Contract. SW-846 protocols for Level 3
data were to be used to analyze soil and water samples
during this demonstration. All samples were to be
extracted by EPA Method 3540A and analyzed by EPA
Method 8270A. Any soil samples in which PCP was not
detected using Method 8270A were to be reanalyzed by
Method 8151A calibrated to PCP. Any groundwater
samples in which PCP was not detected using
Method 8270A were to be reanalyzed using
Method 515.1. All of these analytical methods are well
established and approved by EPA. QA procedures,
reporting requirements, and data quality objectives of
these methods are consistent with the goals of the SITE
Program.
Training Technology Operators
Analysis with the FASP PCP Method was conducted
by a PRC operator. Before the demonstration began, this
individual was trained in how to use the method. The
training involved a review of operating procedures and
instruction provided by the lead chemist.
Predemonstration Sampling and Analysis
hi July 1993, PRC prepared a predemonstration
sampling plan (PRC 1993a), and on July 12, 1993, PRC
collected predemonstration soil samples from areas at the
former Koppers facility previously identified as containing
high, medium, low, and not detected concentrations of
PCP. PRC analyzed one replicate of each sample using
the FASP PCP Method. Predemonstration samples did
not exhibit their expected PCP concentrations. These
samples were not analyzed by a confirmatory laboratory
because the contracts for the confirmatory analyses were
not yet finalized. No predemonstration samples were
collected from Winona Post because this site had not been
added to the demonstration plan at the time of the
predemonstration sampling.
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Section 4
Demonstration Design and Description
This section describes the organization of the
demonstration, presents an overview of the
demonstration's design, and details all deviations from
the developer- and EPA-approved demonstration plan.
Among the key portions of the demonstration plan
presented here are the types of data collected and the
statistical methods used to determine the accuracy and
precision of the technology. A detailed description of
the demonstration is presented in the demonstration plan
(PRO 1993b).
Demonstration Design
The primary objective of the demonstration was to
evaluate the FASP PCP Method for its effectiveness in
detecting PCP in soil and water when operated in field
conditions. This objective included defining the
precision, accuracy, cost, and range of usefulness for the
technology. A secondary objective was to define data
quality objectives that the technology can be used to
address. The evaluation was designed so that results
from the technology could be compared to those of a
confirmatory laboratory that analyzed each sample using
standard EPA-approved methods. The design limited, as
much as possible, those elements of sample collection
and analysis that would interfere with direct comparison
of the results. These elements included heterogeneity of
the samples and interference from other chemicals or
other controllable sources.
The design also insured that the data was collected
in a normal field environment. To achieve this, the
method was used in a trailer located at the former
Koppers site. The operator was trained by the PRC lead
chemist. However, the operator obtained all results on
his own and reported the results once he believed the
results were accurate and precise. Standard QC samples
were analyzed with each batch of environmental
samples. Numerous laboratory and field duplicate
samples were included among those analyzed to insure
a proper measure of precision. The technology was also
tested for common interferants. Qualitative measures,
such as portability and ease of operation, were noted by
the operator.
Overall, the demonstration was executed as
described in the demonstration plan (PRC 1993b), which
included the QAPP. The final version of the plan was
approved by all participants and developers before the
demonstration began.
Implementation of the Demonstration Plan
For the demonstration, PRC collected 98 soil
samples, 14 soil sample field duplicates, 10 water
samples, and 6 water sample field duplicates. Each soil
sample was thoroughly homogenized and then split into
replicate samples. One replicate from each sample was
submitted to the confirmatory laboratory; another
replicates was analyzed in a trailer at the former
Koppers site using the FASP PCP Method. In addition
to these samples, two soil performance evaluation (PE)
samples and three water PE samples were analyzed.
The final demonstration plan called for the
collection of 90 soil samples with the following
distribution: (1) 40 samples containing 0 to 100 ppm
PCP; (2) 25 samples containing 100 to 1,000 ppm PCP;
and (3) 25 samples containing greater than 1,000 ppm
PCP. During this demonstration, 98 soil samples were
collected. The actual distribution of these samples,
when the demonstration was complete, was as follows:
(1) 60 samples contained 0 to 100 ppm PCP;
(2) 16 samples contained 100 to 1,000 ppm PCP; and
(3) 22 samples contained greater than 1,000 ppm PCP.
This skewing of the sample set to the 0 to 100 ppm range
should not affect the usability of this report, because the
majority of EPA PCP soil action levels occur in the
20 to 100 ppm range.
Of the samples collected for the demonstration,
53 soil samples, 9 soil field duplicates, 5 water samples,
and 5 water field duplicate samples were collected at the
former Koppers site. Soil samples were collected from
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areas known to exhibit a wide range of PCP
concentrations. The areas sampled ranged in PCP
concentration from not detected to 3,220 ppm. Most of
the samples were collected from areas characterized
during the remedial investigation. Water samples were
collected from five existing groundwater monitoring
wells located on the former Koppers site. The PCP
concentrations in these wells were well documented from
past sampling. The PCP concentrations sampled ranged
from not detected to nearly 1,500 ppb.
Of the samples collected for the demonstration,
45 soil samples, 5 soil field duplicates, 5 water samples,
and 1 water duplicate sample were collected at the
Winona Post site. Soil samples were collected in areas
believed to be contaminated with high (greater than
1,000 ppm), medium (100 to 999 ppm), and low (less
than 99 ppm) concentrations of PCP. The identification
of these areas was based on past sampling data and
visual signs of waste disposal. Water samples were
collected from the only surface water located on or near
the site. All of the Winona Post samples were collected,
packaged, and shipped to the former Koppers site using
methods detailed hi the demonstration plan (PRC
1993b).
Field Modifications to the Demonstration
Plan
Two field modifications were made to the approved
demonstration plan. First, fluorescein was not added to
soil samples from the former Koppers site. The nature
of the soil samples at both the former Koppers site and
the Winona Post site allowed easy and thorough
homogenization. The saturated stiff clay matrix for
which the fluorescein additions were designed was not
encountered at the former Koppers site and thus, for
consistency, this technique was eliminated at both sites.
PRC believes that die elimination of the fluorescein from
the homogenization process was offset by the long
homogenization times used during this demonstration.
To further examine mis approach, PRC conducted a
side-by-side comparison of homogenization with and
without fluorescein. Samples from the former Koppers
site were used for this comparison. The dry nature of
the soil required that it be hydrated with water to allow
visible distribution of the fluorescein. The addition of
water and fluorescein caused a two-unit increase hi the
soil sample pH. This alteration of the sample chemistry
coupled with the reactive nature of PCP invalidated the
fluorescein homogenization approach for environmental
applications. PRC used an EPA-approved homo-
genization method and applied it to each sample for 10
to 15 minutes. This method involved vigorous kneading
of the sample in a clear plastic bag.
The second modification to the approved
demonstration plan involved sampling die water matrix.
This change was made because me EPA Region 7
project sponsor altered the design of the demonstration
with regard to die evaluation of the water assays. The
EPA sponsor required that the number of water samples
collected and analyzed for the demonstration be reduced
to a total of 5 to 10 samples. The approved demon-
stration plan called for the collection of 50 groundwater
samples. To maximize the usefulness of the reduced
number of water samples, PRC and EMSL-LV agreed to
combine data from both sites if they could be shown
statistically to come from the same distribution, thereby
increasing the sample set size. Also, the EPA Region 7
sponsor agreed to allow the following: (1) die Region 7
Laboratory would split and analyze samples from
Winona Post hi sample-plus duplicate (split) pairs;
(2) excess water from the original Winona Post water
sample that was duplicated would be used for laboratory
QA/QC; and (3) only five monitoring wells would be
sampled at the former Koppers site, and each sample
would be duplicated. This approach would have resulted
in five paired samples (the sample plus its duplicate)
from each site. This in turn would have provided five
samples from each site for an accuracy assessment, and
five paired samples from each site for a precision
assessment. Although these are minimal sample sizes,
diis design was believed to provide the most useful data
given the reduction hi analytical resources mat the EPA
Region 7 sponsor required. However, when PRC
delivered the soil and water samples from the former
Koppers site, it learned that die Winona Post water
samples had been extracted and analyzed as they were
delivered, that is, as five environmental samples with
one duplicate. This failure to follow the modified
experimental design resulted hi only four single sample
results and one duplicate result for precision analysis for
this data set. The Koppers data set consisted of five
duplicate pairs.
Data Collection
The technology operator prepared a subjective
evaluation of how difficult me technology was to use.
Other qualitative measures assessed included portability,
ruggedness, instrument reliability, and health and safety
considerations. Information on these qualitative factors
was collected both by the operator of the technology and
by the lead chemist. To evaluate accuracy and
precision, all samples collected for analysis were split
between the technology and the confirmatory laboratory.
Statistical methods used to compare the results of die
two methods are detailed below. The cost of using mis
technology was also assessed. Cost, for the purposes of
this demonstration, included expendable supplies,
nonexpendable equipment, labor, and investigation-
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derived waste (IDW) disposal. These costs were tracked
during the demonstration.
Statistical Analysis of Results
For both the innovative technology and the
confmnatory laboratory, two data sets were created: one
for soil samples and the other for water samples. In
addition, each water and soil data set was composed of
two subsets, one for the samples taken from the former
Koppers site and one for those collected at the Winona
Post site. This grouping was intended to assess potential
PCP carrier effects. A third data separation involved
grouping the site-specific data sets into results greater
than 100 ppm PCP and less than 100 ppm PCP. This
grouping was intended to assess potential concentration
effects on the data analysis.
These data sets were prepared for the statistical
analysis following methods detailed in the approved
demonstration plan. When comparing duplicate samples
or when comparing the results of a technology to those
from the confirmatory laboratory, sample pairs that
contained a nondetect were removed from the data sets.
While other statistical methods can be used when
nondetects are encountered, PRC believed that the
variance introduced by eliminating these data pairs
would be less than, or no more than equal to, the
variance produced by giving not detected results an
arbitrary value.
Intramethod Comparisons
Sample results from the technology were compared
to their duplicate sample results and to other QA/QC
sample results. These comparisons are called
intramethod comparisons. Intramethod accuracy was
measured by assessing each technology's performance in
analyzing PE samples. If the method produced a result
considered accurate by the company that produced the
PE samples, the technology was considered to have
acceptable intramethod accuracy for this demonstration.
Intramethod precision was assessed through the statistical
analysis of relative percent differences (RPD). First,
RPDs of the results for each sample pair, in which both
the sample and its duplicate were found to contain PCP,
were determined. RPDs then were compared to upper
and lower control limits. When using conventional
technologies, such data is often available from analysis
of samples collected during previous investigations.
Because the technology being demonstrated was itself
being assessed, the control limits used were calculated
from data provided during this investigation. To
determine these control limits, the standard deviation of
the RPDs was calculated for each technology. This
standard deviation was then multiplied by two and added
to its respective mean RPDs. This established the upper
control limit for the technology. Because an RPD of
zero would mean that the duplicate samples matched
their respective samples perfectly, zero was used as the
lower control limit. This resulted in a large range of
acceptable values. Because duplicate analyses seldom
match perfectly, even for established technologies, all
samples that fell within the control limits were
considered acceptable. PRC determined that if at least
90 percent of the duplicate samples fell within these
control limits, the technology had acceptable intramethod
precision.
Intermethod Comparisons
Data sets from the FASP PCP Method also were
statistically compared to results from the confirmatory
laboratory, and the precision of the method was
statistically compared to the precision of the
confirmatory laboratory. These comparisons are called
intermethod comparisons. In both cases, results from
the confirmatory laboratory were considered to be as
accurate and precise as analytically possible. Statistical
methods used to determine intermethod accuracy
included linear regression analysis and the Wilcoxon
Signed Ranks Test. Before undertaking the regression
analysis, PRC further prepared the data sets by
averaging the field duplicate results. This approach
ensured that samples were not unduly weighted. PRC
calculated linear regression by the method of least
squares. Calculating linear regression in this way makes
it possible to determine whether two sets of data are
reasonably related, and if so, how closely. Calculating
linear regression produces an equation that can be
visually expressed as a line. Three factors are
determined during calculations of linear regression: (1)
the y-intercept, (2) the slope of the line, and (3) the
correlation coefficient, also called an r2. All three of
these factors must have acceptable values before a
technology's accuracy was considered to meet Level 3
data quality requirements.
The r2 expresses the mathematical relationship
between two data sets. If the r2 is one, then the two data
sets are directly related. Lower r2 values indicate less of
a relationship. Because of the heterogeneous nature of
environmental samples, r2 values between 0.85 and
1 were considered to meet data quality Level 3 accuracy
requirements; r2 values between 0.75 and 0.85 were
considered to meet data quality Level 2 accuracy
requirements; and r2 values below 0.75 were considered
not accurate, meeting only Level 1 accuracy
requirements at best.
If the regression analysis resulted hi an r2 between
0.85 and 1, then the regression line's y-intercept and
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slope were examined to determine how closely the two
data sets matched. A slope of one and a y-intercept of
zero would mean that the results of the technology
matched those of the confirmatory laboratory perfectly.
Theoretically, the farther the slope and y-intercept differ
from these expected values, the less accurate the
technology. Nevertheless, a slope or y-intercept can
differ slightly from their expected values without that
difference being statistically significant. To determine
whether such differences were statistically significant,
PRC used the normal deviate test statistic. This test
statistic results hi a value that is compared to a table.
The value at the 90 percent confidence level was used
for the comparison. To meet data quality Level 3
requirements, both the slope and y-intercept had to be
statistically the same as their ideal values.
If the r2 was between 0.75 and 0.85, and one or
both of the other two regression parameters were not
equal to their ideal, the technology was considered to be
inaccurate but producing Level 2 quality data. Results
in this case could be mathematically corrected if 10 to 20
percent of the samples were sent to a confirmatory
laboratory. Analysis of a percentage of the samples by
a confirmatory laboratory would provide a basis for
determining a correction factor. Only in cases where the
r2, the y-intercept, and the slope were all found to be
acceptable did PRC determine that the technology was
accurate, meeting Level 3 data quality requirements.
Data placed hi the Level 1 category had r2 values
less than 0.75, the data was not statistically similar to the
confirmatory data, based on parametric testing, or the
results did not meet the manufacturer's performance
specifications.
A second statistical method used to assess the
intermethod accuracy of the data from each technology
was the Wilcoxon Signed Ranks Test. This test is a
nonparametric method used to compare matched pairs of
data. It can be used to evaluate whether two sets of data
are significantly different. The test requires no
assumption regarding the population distribution of the
two sets of data being evaluated other than that the
distributions will occur identically. In other words,
when one data point deviates, its respective point hi the
other set of data will deviate similarly. Because the only
deviation expected during the demonstration was a
difference hi the concentrations reported by each
technology, the two sets of data were expected to deviate
in the same way. The Wilcoxon Signed Ranks Test
calculation uses the number of samples analyzed and a
ranking of the difference between the result obtained
from the demonstrated technology and the corresponding
result from the confirmatory laboratory. The rankings
can be compared to predetermined values on a standard
Wilcoxon distribution table, which indicates whether,
overall, the two methods have produced similar results.
Finally, the precision of the technology was
statistically compared to the precision of the
confirmatory laboratory using Dunnett's Test. This test
was used to assess whether the precision of the
technology and that of the confirmatory laboratory were
statistically equivalent. First, PRC determined the mean
RPD for all samples and their respective duplicates
analyzed by the confirmatory laboratory. The RPD of
each duplicate pair analyzed by each of the technologies
was then statistically compared to this mean. It should
be noted that a Dunnett's result showing the precisions
are not similar does not mean that the precision of the
technology was not acceptable, only that it was different
from the precision of the confirmatory laboratory. In
particular, the Dunnett's Test has no way of determining
whether or not any difference between the two data sets
actually resulted because a technology's data was more
precise than the confirmatory laboratory's. The
Dunnett's results were verified by the Wilcoxon Signed
Ranks Test.
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Section 5
Confirmatory Analysis Results
All samples collected during this demonstration
were submitted to the EPA Region 7 Laboratory for
confirmatory analysis. Water samples were analyzed by
the EPA Region 7 Laboratory under the ESAT Contract,
and soil samples were analyzed under the RECAP
contract. The ESAT Contract analysis was conducted at
the EPA Region 7 Laboratory. The EPA Region
7 Laboratory forwarded all soil samples to the RECAP
Laboratory. Discussion of the analyses at both
laboratories is presented below. Analytical data
provided by the confirmatory laboratories is shown in
Section 6 with that of the FASP PCP Method.
Confirmatory Laboratory Procedures
EPA Region 7 Laboratory Quality Assurance and
Data Evaluation (QADE) Branch personnel conducted a
Level 2 data review on results provided by the
confirmatory laboratories. A Level 2 data review does
not evaluate raw data or check calculated sample values.
A review of the raw data and a check of the calculations
was performed by QC personnel from each of the
confirmatory laboratories before submitting the data
package to the EPA Region 7 Laboratory QADE
Branch. PRC was not able to review all of the raw data
generated from the analysis of samples. However, PRC
did review the laboratory case narratives and the EPA
Region 7 Laboratory QADE Branch comments generated
by the Level 2 data review.
The following sections discuss specific procedures
used to identify and quantitate semivolatile organic
compounds (SVOC), and specifically PCP, using the
following methods: SW-846 Method 8270A (soil and
water), SW-846 Method 8151A (soil), and EPA Method
515.1 (water).
Sample Holding Times
All of the analytical methods used for confirmatory
analysis require that all sample extractions be completed
within 7 days from the time a sample is collected. Due
to the stability of PCP, EPA's ORD Methods Validation
Section extended these holding time requirements by
4 days for this demonstration. All sample extracts must
be analyzed within 40 days of validated sample receipt.
All holding time requirements were met for samples
collected during this demonstration.
Sample Extraction
EPA Method 3550 was used to extract soil samples
prior to analysis by EPA Method 8270A. This method
involves sonication extraction of the soil using methylene
chloride. The confirmatory laboratory used both the low
concentration extraction method and the high
concentration extraction method discussed in EPA
Method 3550. To determine the appropriate extraction
method to use for die analysis of individual soil samples,
the confirmatory laboratory screened each sample using
the screening techniques recommended in EPA Method
8270A. EPA Method 3510A was used to extract water
samples and involves a separatory extraction of the water
with methylene chloride. To ensure that phenolic
compounds, such as PCP, were adequately extracted
from the water samples, two extractions of each water
sample were performed. The pH of the water was
adjusted to greater than 12 and extracted, then the pH of
the water sample was adjusted to below 2 and extracted.
The two sample extracts were then combined for sample
analysis.
Low-level detection analytical methods for PCP
included different procedures for sample extraction. The
method used for the soil samples, EPA Method 8151A,
involves an acidification of the soil sample, followed by
an ultrasonic extraction with methylene chloride. This
extraction is similar to the EPA Method 3550 sonication
extraction. The soil sample extract was then taken
through an acid-base partition to remove potentially
interfering compounds from the sample extract. The
sample extract was then concentrated and taken through
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a diazomethane derivatization. This procedure replaces
the hydrogen atom of the alcohol group with a methyl
anion. This derivatization removes the polarity
associated with PCP and enables improved
chromatographic behavior. PCP standards used for
sample identification and quantitation were taken through
the same derivatization steps as samples to allow a direct
comparison of concentration. That is, no correction
factor needs to be used for the molecular weight of the
derivatization product.
The low level detection analytical method used for
water samples, EPA Method 515.1, involves a separa-
tory extraction of the water sample with methylene
chloride. The pH of the water samples was adjusted in
a similar manner to the pH adjustment used for the water
samples extracted with EPA Method 3510A. In EPA
Method 515.1, the solvent extract from the basic
extraction is discarded because it contains no PCP. This
step also removes potential interferences. The water
sample extract is then concentrated and derivatized in the
same manner as the soil sample extracts. Again, this
derivatization removes the polarity associated with PCP
and provides improved chromatographic behavior. PCP
standards used for sample identification and quantitation
were taken through the same derivatization steps as the
samples to allow a direct comparison of concentration.
Detection Limits and Initial and Continuing
Calibrations
The detection limit for soil samples analyzed by
EPA Method 8270A was reported as 0.330 ppm. The
detection limit for soil samples analyzed by EPA Method
8151A was reported as 0.076 ppm. The reported
detection limit for water samples analyzed by EPA
Method 8270A was 50 ppb. The detection limit for
water samples analyzed by EPA Method 515.1 was
reported as 0.076 ppm. Method-required initial and
continuing calibration procedures were appropriately
conducted, and all method-required criteria for these
calibrations were met.
Sample Analysis
The confirmatory laboratories performed sample
analysis by first analyzing samples using EPA
Method 8270A. Based upon the screening results, the
samples were extracted with either the low concentration
method or the high concentration method found hi EPA
Method 3550. Samples that did not provide a positive
response for PCP with EPA Method 8270A were
analyzed by one of two low-level detection methods:
EPA Method 8151A for soil samples and EPA Method
515.1 for water samples.
For EPA Method 8270A, compound identification
was required to meet two criteria: (1) the sample
component relative retention time was to fall within
± 0.06 relative retention time units of the standard
component, and (2) the mass spectrum of the sample
compound was to correspond with the standard
compound mass spectrum.
Soil and water samples found to contain no PCP
during the EPA Method 8270A analysis were analyzed
using EPA Methods 8151A and 515.1, respectively.
The presense of PCP was identified if a sample peak
eluted within the retention time window established
during the initial calibration.
Quality Control Procedures
Method blanks are used to monitor the presence of
laboratory-induced contamination. The EPA Region
7 Sample Management Office (SMO) provided blank soil
and blank water samples for use as method blank
samples during the analysis of demonstration samples.
An acceptable method blank must not provide a positive
response for the target compounds above the reported
detection limit. Method blank samples were stored,
extracted, and analyzed in exactly the same manner as
the demonstration samples. Results for all method blank
samples extracted and analyzed along with the
demonstration were found to be acceptable.
Internal standards were used to analyze
demonstration samples by EPA Method 8270A. Internal
standards were added to all standards, blanks, samples,
and QC samples prior to injection into the analytical
system. The internal standards were used to provide
response factors for each of the target compounds.
During the analysis of soil samples, seven samples
exhibited internal standard responses that were outside of
the QC limits of 50 to 150 percent recovery. All of the
affected samples provided internal standard responses
that were less than 50 percent. The soil samples affected
were samples 038, 060, 062, 068, 090, 091, and 095.
Three of these samples (090, 091, and 095) were found
to contain no detectable levels of PCP, and no corrective
action was taken. Instead, they were reanalyzed using
EPA Method 8151A. The remaining samples were
reanalyzed to verify that the internal standard response
was below 50 percent recovery. The reanalysis showed
that internal standard response was below 50 percent
recovery. No corrective action was taken by the
laboratory, which attributed the low recovery to matrix
effects inherent to the samples. In the Region
7 Laboratory QADE Branch review of the data, the
same conclusion was reached.
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Surrogate standards were used to evaluate the
efficiency of the extraction and analysis processes and to
evaluate matrix affects. Surrogate standards used for
EPA Method 8270A include deuterated standards that
provide a different mass spectrum when compared to the
nondeuterated compound. All surrogate standard
recoveries for soil samples fell within the acceptance
ranges. The data review performed by Region 7 QADE
indicated that surrogate recoveries for some of the water
samples were outside of the acceptance ranges, but no
information indicated which samples or how many
samples fell outside surrogate recovery acceptance
ranges. Corrective action was not taken because the
acceptance ranges listed in the method are for advisory
purposes only. The surrogate standard used for EPA
Methods 8151A and 515.1 was 2,4-dichlorophenylacetic
acid (DCAA). The acceptance range for DCAA was
determined by the RECAP and Region 7 Laboratories
through a statistical analysis of 30 or more standard
surrogate recoveries. The mean and standard deviation
were then calculated, and the acceptance range was
determined by applying a ± 3 standard deviations
around the mean. All samples analyzed by EPA
Methods 8151A and 515.1 provided surrogate recoveries
that fell within the laboratory-generated control limits.
Matrix spike samples consisted of aliquots of
original sample with a known concentration of the target
compounds added. The EPA Region 7 Laboratory SMO
designated the samples to be used as matrix spike
samples. Designated soil samples included samples
036, 048, 053, 073, 087, and 098, all analyzed using
EPA Method 8270A, and sample 089, analyzed using
EPA Method 8151 A. Designated water samples
included samples 101 and 111, analyzed using EPA
Method 515.1, and sample 104, analyzed using EPA
Method 8270A. Soil matrix spike samples analyzed
using EPA Method 8270A were spiked with all the target
compounds reported by the method. Water sample
matrix spike samples analyzed using EPA Method
8270A were spiked with nine of the target compounds
reported by the method. Matrix spike samples analyzed
with EPA Methods 8151A and 515.1 were spiked with
only PCP. Soil matrix spike data for PCP is shown in
Table 5-1, and water matrix spike data for PCP is shown
in Table 5-2.
Soil sample matrix spike recoveries were greatly
influenced by the high concentrations of PCP present in
the original sample relative to the amount spiked. Only
sample 098 resulted hi recoveries for both the matrix
spike and matrix spike duplicate sample that could be
considered acceptable. A clear evaluation of the effects
of matrix on PCP recovery is not possible due to the
high concentrations of PCP in the original sample and
the comparatively low levels of PCP added to the matrix
spike samples. The water sample matrix spike sample
analyzed by EPA Method 8270A resulted in high
recoveries. These recoveries are on the high end of the
QC acceptance criteria for PCP recoveries listed in EPA
Method 8270A (14 to 176 percent recovery). However,
the agreement between the matrix spike and matrix spike
duplicate was excellent as determined by the RPD of the
matrix spike recoveries. The water matrix spike samples
analyzed using EPA Method 515.1 were affected by the
concentration of PCP in the original sample. Although
the matrix spike recoveries for sample 101 were found
to be acceptable, the recoveries of PCP spiked into the
sample were affected by the much larger concentration
of PCP in the original sample. Sample 111 also was
affected by the concentration of PCP in the original
sample. Results of both the matrix spike sample and the
matrix spike duplicate sample were less than the result
for the original sample, which may indicate a
heterogeneity problem with the sample. The low levels
of PCP added to this sample were not enough to obtain
an accurate indication of matrix spike recovery.
The EPA Region 7 Laboratory SMO prepared blank
spike samples for water samples analyzed by EPA
Methods 8270A and 515.1. These samples were used to
evaluate the accuracy of the laboratory. Blank spike
samples were stored, extracted, and analyzed in the
same manner as all other samples. The percent
recoveries of the blank spike samples fell within the
14 to 176 percent QC acceptance criteria listed hi EPA
Method 8270A and the 67.6 to 192.4 percent acceptance
criteria listed hi EPA Method 515.1. The accuracy of
the analysis of water samples using EPA Methods 8270A
and 515.1 was found to be acceptable, based on the
blank spike sample results.
Data Reporting
The data report PRC received from the EPA Region
7 Laboratory included a standard EPA Region 7 Analysis
Request Report. Results were reported on a dry weight
basis, as required hi the methods. PRC obtained data on
the loss-on-drying determination for each of the samples.
The loss-on-drying values were used to convert the
confirmatory laboratory data from a dry weight basis to
a wet weight basis.
Results were reported by the confirmatory
laboratory hi micrograms per kilogram (/ig/kg) for soil
samples and micrograms per liter (/tg/L) for water
samples. Soil sample results were converted to
milligrams per kilogram (mg/kg) so they could be
compared to the results from the technology, which
reported results for soil samples in milligrams per
kilogram. The technology's results for water samples
14
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TABLE 5-1. SOIL MATRIX SPIKE SAMPLE RESULTS FOR EPA METHODS 8270A AND 8151A
Amount Found Amount Added to Amount Amount Found Duplicate Relative
in Original Matrix Spike and Found in Percent in Matrix Spike Percent Percent
Sample Sample Duplicate Matrix Spike Recovery Duplicate Recovery Difference
No. (ppm) (ppm) (ppm) (%) (ppm) (%) {%)
036
048
053
073
087
089
098
40.0
30,000
2.30
86.0
46.0
0.247
0.70
1.90
46.0
1.50
11.0
1.40
0.098
0.41
66.0
22,000
12.0
130
57.0
0.315
0.82
1,370
0
647
400
786
69
29
51.0
24,000
5.20
93.0
64.0
0.241
0.98
579
0
193
64
1,285
0
68
81
0
108
145
48
200
80
TABLE 5-2. WATER MATRIX SPIKE SAMPLE RESULTS FOR EPA METHODS 8270A AND 515.1
Amount Found Amount Added to
in Original Matrix Spike and
Sample Sample Duplicate
No. (ppb) (ppb)
Amount Amount Found Duplicate Relative
Found in Percent in Matrix Spike Percent Percent
Matrix Spike Recovery Duplicate Recovery Difference
(ppb) (%) (ppb) (%) (%)
101
104
111
4.14
50.0 U
1.85
0.446
200
0.398
4.46
348
1.55
72
174
0
4.24
353
1.64
22
177
0
106
2
0
were reported in micrograms per liter, so no conversion
of the confirmatory laboratory data was needed.
Data Quality Assessment
Accuracy refers to the difference between the
sample result and the true concentration of analyte in the
sample. Bias, a measure of the departure from complete
accuracy, can be caused by such processes as loss of
analyte during the extraction process, interferences, and
systematic contamination or carryover of an analyte from
one sample to the next. Accuracy for the confirmatory
laboratory was assessed by using PE samples. Four of
the PE samples used for this demonstration were
purchased from Environmental Resource Associates
(ERA). Two of these PE samples were soil and two
were water. These samples contained a known quantity
of PCP. ERA supplied data sheets for each PE sample
that included the true concentration and an acceptance
range for the sample. The acceptance range was based
on the 95 percent confidence interval taken from data
generated by ERA and EPA interlaboratory studies. A
third water PE sample was prepared by the PRC lead
chemist to widen the range covered by the PE samples.
These samples were extracted and analyzed in the
same manner as the other water and soil samples. The
confirmatory laboratory did not know which samples
were PE samples or the certified values and acceptance
ranges. The true value concentration of soil PE sample
099 (the low-level sample) was 7.44 ppm, with an
acceptance range of 1.1 to 13 ppm. The result reported
by the confirmatory laboratory for this sample was
4.02 ppm, which was within the acceptance range. The
percent recovery of this sample by the confirmatory
laboratory was 54 percent. The true concentration of soil
PE sample 100 (the high-level sample) was 101 ppm
with an acceptance range of 15 to 177 ppm. The result
reported for this sample by the confirmatory laboratory
was 52.4 ppm, which was within the acceptance range.
The percent recovery of this sample by the confirmatory
laboratory was 52 percent.
The true value concentration of water PE sample
106 (the low-level sample) was 68.4 ppb with an
acceptance range of 10 to 120 ppb. The result reported
by the confirmatory laboratory for this sample was
10.3 ppb, which was within the acceptance range. The
percent recovery of this sample by the confirmatory
laboratory was 15 percent. The true concentration of
15
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water PE sample 107 (the high-level sample) was
2,510 ppb with an acceptance range of 377 to 4,420 ppb.
The result reported for this sample by the confirmatory
laboratory was 2,050 ppb of PCP, which was within the
acceptance range. The percent recovery of this sample
by the confirmatory laboratory was 82 percent. The true
value concentration of water PE sample 113 (the PE
sample prepared by PRC) was 7.50 ppb. No acceptance
range was statistically determined for this PE sample.
Instead, PRC established a 30 to 170 percent window of
acceptable values around the true value result of the
low-level PE sample. This window is consistent with
both the acceptance ranges of the PE samples prepared
by ERA and the QC Acceptance Criteria for PCP
recovery stated in EPA Method 8270A. The
confirmatory laboratory result for this PE sample was
within the acceptance range. Based on results for all of
the PE samples, the accuracy of the confirmatory
laboratory was acceptable.
Precision refers to the degree of mutual agreement
among individual measurements and provides an estimate
of random error. Precision for results obtained by
confirmatory laboratory was determined by using field
duplicate samples. Normally, laboratory duplicates are
used to determine precision. However, no laboratory
duplicates were analyzed by the confirmatory
laboratories. Field duplicates are two samples collected
together but delivered to the laboratory with separate
sample numbers. Typically, field duplicate samples are
used to measure both sampling and analysis error. PRC
established control limits for field duplicate RPDs.
These control limits are similar to those used to
determine matrix spike recovery acceptance control
limits. To establish the control limits, all sample pairs
that did not produce two positive results were removed
from the data set. Then the RPD for each pair was
calculated, and the mean RPD and standard deviation
were determined. The lower control limit was set at
zero because this would mean that the results from a
duplicate and its sample matched perfectly. The upper
control limit was set by multiplying the standard
deviation by two and adding it to the mean RPD. The
RPD of each sample pair was then compared to these
control limits. Each sample pair RPD was expected to
fall within the control limits.
Fourteen soil field duplicate samples were collected
and analyzed by the confirmatory laboratory during this
demonstration. Field duplicate samples represented
17 percent of all soil samples collected and analyzed.
The original results ranged from 0.10 to 26,100 ppm.
Duplicate sample results ranged from 0.09 to
30,260 ppm. RPD values for the soil field duplicate
pairs ranged from 1 to 168 RPD. The mean RPD value
of the soil field duplicate pairs was 33 percent, with a
standard deviation of 47 percent. For the soil field
duplicate pairs the control limits were found to be 0 to
128 RPD. Thirteen of the fourteen, or 93 percent, of
the field duplicate sample pairs fell within this range.
Six water field duplicate samples were collected and
analyzed by the confirmatory laboratory during this
demonstration. Field duplicate samples represented
32 percent of all water samples collected and analyzed.
The original results ranged from 0.175 to 1,810 ppb.
The field duplicate sample results ranged from 0.63 to
2,020 ppb. RPD values for the water field duplicate
pairs ranged from 0 to 113 RPD. The mean RPD value
of the water field duplicate pairs was 30 percent with a
standard deviation of 41 percent. For the water field
duplicate pairs, the control limits were found to be 0 to
112 RPD. Five of the six, or 83 percent of the field
duplicate sample pairs, fell within this range.
Completeness refers to the amount of data collected
from a measurement process compared to the amount
expected (Stanley and Verner 1983). For this
demonstration, completeness referred to the proportion
of valid, acceptable data generated by the confirmatory
laboratory. The completeness objective for this project
was 95 percent. This demonstration resulted in the
analysis of 98 soil samples, 14 soil sample duplicates,
2 soil PE samples, 10 water samples, 6 water sample
duplicates, and 3 water PE samples. Results were
obtained for all of these samples. Completeness for the
confirmatory laboratory was 100 percent.
Confirmatory Laboratory Costs
and Turnaround Times
The cost for performing PCP analysis by EPA-
approved analytical methods varies from laboratory to
laboratory. The cost of analysis depends on the number
of samples submitted for analysis, the matrix, and the
level of QC performed. The following costs are given
as general guidelines. EPA Method 8270A analysis
costs range from $250 to $400 per sample. EPA
Method 8151A analysis costs range from $150 to
$250 per sample. EPA Method 515.1 analysis costs
range from $125 to $200 per sample. Turnaround times
for samples submitted for analysis with EPA-approved
analytical methods range from 14 to 30 days. The
turnaround tune also depends on the number of samples
submitted for analysis, the matrix, and the level of QC
performed. Faster turnaround times may be available
for an additional cost.
16
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Section 6
EPA Region 7 Super-fund Program: FASP PCP Method
The FASP PCP Method was developed by the EPA
Region 7 Superfund Branch under the Field Investigation
Team Contract for use at Superfund sites. It was
designed to provide quick, accurate results to determine
PCP concentrations in soil and water samples. This
method can also detect and quantify other phenols. PCP
concentrations are reported in either ppb or ppm for soils
and hi ppb for water. The method uses a GC equipped
with a megabore capillary column and an FID and ECD
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 the EPA-approved methods.
Operational Characteristics
The instruments and equipment required for the
FASP PCP Method are not very portable because of
their large sizes. The equipment used includes the
following: (1) a Shimadzu GC-14A equipped with an
FID and ECD, (2) a Shimadzu AOC-14 autosampler,
(3) a Shimadzu CR-4AX data system, and (4) a
COMPAQ SLT/286 laptop computer. The GC weighs
100 pounds with its autosampler attached and measures
18 inches by 24 inches by 12 inches. The data system
weighs another 25 pounds and is the same size. In
addition to this equipment, the following laboratory
equipment is necessary: (1) Nitrogen carrier gas; (2) a
DB-5, 30-meter, 0.53-millimeter inside diameter, or
equivalent capillary column; (3) 10-, 50-, and
100-microliter micropipettes; (4) 10-, 25-, 50-, 100-,
and 500-microliter micro syringes; (5) 1-, 5-, and
10-milliliter glass volumetric pipets; (6) 2- to
10-milliliter repipetter with Teflon liners; (7) 10-, 50-,
and 100-milliliter glass volumetric flasks with ground-
glass stoppers; (8) 2-milliliter glass vials with Teflon-
lined cap for storing stock standards; (9) 2-milliliter
autosampler vials with Teflon-lined cap; (10) a bubble
flow meter used to check GC column flows; (11) 4-fluid-
ounce standard bottles with Teflon-lined screw cap for
calibration standard storage; (12) 5.75- and 9-inch
disposable glass Pasteur pipets; (13) 40-milliliter
extraction vials with Teflon-lined screw caps; (14)
13- by 100-millimeter test tubes with Teflon-lined screw
caps; (15) stainless-steel spatulas; (16) top loader balance
with 0.01-gram accuracy; (17) a high speed vortex
mixer; (18) a digital timer; (19) large and small pipet
bulbs to fit volumetric and Pasteur pipets; (20) labels;
(21) permanent markers; (22) paper towels; (23) surgical
gloves; (24) safety glasses; (25) laboratory coats or other
protective clothing; (26) refrigerator; (27) a fume hood;
and (28) floppy disks. The following reagents are
needed for sample extraction and analysis using the
FASP method: (1) pesticide-grade or equivalent methyl-
tert-butyl ether; (2) granular, pesticide-grade sodium
sulfate; (3) concentrated Fisher Scientific or equivalent
sulfuric acid; (4) powdered sodium bicarbonate for
neutralizing acid spills; (5) Fisher Scientific or
equivalent potassium hydroxide; and (6) 98 percent
purity or greater phenol standards.
The FASP PCP Method must be performed indoors
in a temperature-controlled environment to protect the
analytical equipment from moisture and temperature
extremes. Most of the other equipment and reagents
also require this protection. During this demonstration,
the FASP method was performed in an air conditioned
trailer.
Another logistical requirement of the technology is
electricity. Electricity was provided to the trailer
through a temporary power pole. An alternative source
of electricity may be used, such as a gasoline-powered
generator. The use of a generator allows the analytical
equipment to be operated even at the most remotely
located sites. Electricity is also required for various
support equipment. The method requires using a fume
hood to evacuate solvent and acid fumes from the work
area. The fume hood may be vented directly outdoors or
internally through a charcoal filter that traps harmful
fumes. A refrigerator is needed to store the PCP
standards. The refrigerator used for this demonstration
was 3.5 cubic feet hi size. Carrier, make-up, and FID
flame gases are required for gas chromatography.
17
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The work space required for the analytical
equipment is 12 square feet. Another 8 square feet is
needed to perform sample extraction and preparation
steps. Storage space for equipment, reagents, and
glassware also is needed. A solvent storage cabinet for
flammable solvents is recommended for safely storing
solvents. Soil and water samples should be cooled until
sample analysis. They also should not be stored with
PCP standards.
The operator chosen to analyze samples for this
demonstration was Mr. Ramarao Rayavarapu, an
employee of PRC. Mr. Rayavarapu earned a B.S.
degree in civil engineering in 1983 from Andhra
University in India. Mr. Rayavarapu also earned an
M.S. in environmental engineering in 1990 from the
University of Missouri. While at PRC, Mr. Rayavarapu
has conducted RCRA facility inspections, compliance
evaluation inspections, and field sampling and oversight
work. His experience also includes using several types
of wet chemical analytical methods. While attending the
University of Missouri, Mr. Rayavarapu worked as a
laboratory research assistant for 2 years, analyzing liquid
and soil samples using a GC and a high performance
liquid chromatograph. Mr. Rayavarapu was also the
operator for a similar demonstration of the FASP
Polychlorinated Biphenyl Method, also a GC method.
Mr. Rayavarapu was trained for this demonstration by
the lead chemist. Training included 1 week of hands-on
work using and maintaining the GC, as well as training
in specific procedures required for the extraction,
preparation, and analysis of samples.
The FASP PCP Method involves two steps: sample
preparation and sample analysis. Soil sample
preparation involved weighing a known amount of soil
into an extraction vial. A measured portion of sodium
sulfate was added to and mixed with the soil in the
extraction vial. A measured amount of methyl-tert-butyl
ether was added to the extraction vial. The vial was then
mixed with a vortex shaker for 2 minutes. The organic
sample extract was now ready to be analyzed for PCP.
In soil samples suspected of containing petroleum
hydrocarbons, an acid-base cleanup was used to separate
the petroleum hydrocarbons from PCP. The cleanup
was performed by transferring an aliquot of the organic
sample extract to a test tube. A small amount of a
37 percent solution of potassium hydroxide was added to
the test tube and mixed with the organic sample extract
for 1 minute. PCP in the organic sample extract was
converted to a potassium salt that is soluble hi the
aqueous solution. After this basic wash, the organic
solvent was removed from the test tube and the aqueous
phase, containing the PCP-potassium salts, was washed
twice with organic solvent. A small amount of a
1:1 solution of sulfuric acid was carefully added to the
test tube. The pH of the solution was lowered to less
than 2 with the sulfuric acid solution. This step
converted the PCP-potassium salts back to PCP, which
was soluble in the organic solvent. The acidic aqueous
extract was extracted three tunes with methyl-tert-butyl
ether. The organic sample extract was adjusted to a
known concentration and was ready for analysis.
Water extraction was performed by measuring a
volume of water into an extraction vial. The pH of the
sample was adjusted to greater than 10 with a 37 percent
solution of potassium hydroxide. The basic water
sample was extracted three times with methyl-tert-butyl
ether, and the organic solvent containing petroleum
hydrocarbons and other interferences was discarded.
The basic water sample's pH was first adjusted to less
than 2 with a 1:1 solution of sulfuric acid and then
extracted three times with methyl-tert-butyl ether. This
organic sample extract contained PCP. The organic
sample extract was concentrated to a known volume and
was ready for analysis.
Sample preparation, as noted by the operator, was
exhaustive and time-consuming and required an operator
experienced in laboratory procedures. The sample
preparation became more complicated when the sample
had to undergo additional cleanup steps to remove matrix
interferences. Sample analysis required that the operator
be familiar with GC techniques. A minimum of
6 months experience in using a GC and a minimum of
1 month experience hi analyzing PCP is recommended
to effectively use the FASP PCP Method. The operator
noted that operation of the GC was easier for those with
prior GC experience and with a basic knowledge of
analytical chemistry.
The ruggedness of field portable GC equipment has
been demonstrated through years of use. Maintenance
of the GC and other equipment is essential to ensure
quick and accurate PCP results in the laboratory or field.
Because of the rigors of working hi the field, the
equipment should be on site and operating correctly at
least 1 to 2 days before beginning sample collection.
This lead tune allows any travel-induced damage to be
corrected prior to sample collection. Routine
maintenance includes gas bottle changes, septum
changes, and column conditioning. Nonroutine
maintenance may include column changes or electronic
board replacement. Agreements with equipment
suppliers for overnight delivery of replacement parts and
in-the-field servicing by equipment service
representatives may be required to provide all needed
maintenance.
18
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Instrument reliability was evaluated by monitoring
the equipment's ability to maintain its calibration. An
initial calibration (ICAL) was performed at the start of
the demonstration. The instrument calibration was
monitored daily through continuing calibrations (CCAL)
using the mid-level concentration of the PCP standards.
During the CCAL the peak response obtained is
compared to the average peak response obtained during
the ICAL. These responses are compared by determin-
ing the RPD between responses. An RPD value of less
than or equal to 25 percent is required to continue sam-
ple analysis. If the RPD is higher than 25 percent,
another ICAL must be performed. Over the 13 days of
the demonstration, three ICALs and 13 CCALs were
performed. Out of three ICALs, two were performed
for soil analysis, and one was performed for water
analysis. Eleven CCALs were performed for the
analysis of soil samples, and two CCALs were
performed for the analysis of water samples. CCALs
were performed on each day of sample analysis. On the
eleventh day of the demonstration, the CCAL for soil
analysis was out of control as a result of analyzing soil
samples from the Winona Post site, which contained
large amounts of petroleum hydrocarbons. Due to the
heavy contamination with petroleum hydrocarbons in the
samples and extracts, the septa and the glass liner in the
injection port became contaminated, and the column
became saturated with hydrocarbons. After determining
the problem, the septa and the glass liner were replaced,
and the column was conditioned at elevated oven
temperature to desorb the petroleum hydrocarbons.
Another ICAL was performed after column
conditioning; although the relative standard deviation
(RSD) for PCP was 33 percent in the second ICAL, this
RSD was deemed acceptable, and the average calibration
factor was used for sample quantitation. The two
CCALS performed after the second ICAL were within
the new control limits.
A new ICAL was performed for the analysis of
water samples. The CCAL performed for water analysis
was within control limits; however, the CCAL
performed at the end of the analysis did not fall within
control limits. The retention tune of the specific PCP
peak also was monitored through the CCALs. The
retention tune of this peak shifted throughout the
demonstration. To maintain an accurate retention time
window for this peak, the window was adjusted.
Another reliability factor evaluated was the
consistency of the data system to properly draw a
baseline for standards and samples. Baselines were
drawn consistently for samples from the former Koppers
site. However, samples from Winona Post site were
highly contaminated with petroleum hydrocarbons,
causing the baseline to drift.
Operators of the method need to be aware of
hazards due to the chemicals used, particularly methyl
tert-butyl ether (MtBE), sodium sulfate, and sulfuric
acid. MtBE is used to extract PCP from samples and to
dilute standard solutions. MtBE is an explosive and
flammable solvent and should be handled only under a
flame hood. Care should be taken when using MtBE to
avoid inhalation and direct contact with the liquid and
fumes. Ignition sources such as open flames should also
be avoided, and a dry chemical fire extinguisher should
be available hi case of fire. Sodium sulfate is used to
chemically dewater soil samples. Sodium sulfate is a
fine granular powder and can be a skin and eye irritant.
Protective clothing and safety glasses should be worn
when using sodium sulfate. Sulfuric acid is used to
reduce the pH of the samples. Sulfuric acid can cause
chemical burns when spilled on the skin. Chemical-
resistant clothing, gloves, and safety glasses are required
for protection from sulfuric acid. An adequate source of
water should be available in case the acid comes in
contact with the skin. Eyewash solutions also should be
available.
This method uses various types of glassware to
analyze samples. Using glass always presents a
possibility of breakage and injury. Glassware should be
handled in a safe, careful manner. Broken glassware
should not be used and should be disposed of in a safe
manner. The ECD contains Nickel-63, a radioactive
material. The amount of radioactive material in the
ECD is minimal, and it is stored hi a sealed container.
Nevertheless, the container must be checked for possible
leakage twice a year. Leakage of the radioactive
material above federally regulated limits requires
immediate attention. The FID uses hydrogen gas, which
is explosive and stored under high pressure. Care must
be taken to secure the hydrogen gas cylinders to avoid
cylinder damage.
The total cost of the analytical equipment used
during this demonstration was $23,214. This cost
includes the GC equipped with an ECD and FID, the
autosampler, the data system, all equipment required to
set up the GC, and installation. Costs per component
are: $13,149 for the GC; $3,865 for the autosampler;
and $6,200 for the data system. Analytical equipment
can also be rented from a number of companies. A
general survey of current market costs for comparable
equipment indicates ranges from $1,500 to $2,500 per
month. Most rental companies require a minimum
rental tune period, but this may be negotiable. Rental
rates usually include delivery and setup but do not
include GC columns. Many companies also offer rent-
to-own or lease-to-own options for analytical equipment.
The cost of reagents and equipment needed to perform
the extraction, preparation, and analysis of soil samples
19
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using the FASP PCP Method is estimated to be $5,000.
This demonstration required about 370 sample
extractions and injections; these 370 sample extractions
include initial sample analysis, subsequent sample
dilutions, and QA/QC samples. At $5,000, this equates
to about $13.50 per sample.
Operator costs will vary depending on the technical
level of the operator. As discussed earlier, a minimum
of 6 months experience hi using a GC and a minimum of
1 month experience in analyzing samples for PCP is
recommended. Other costs associated with this method
include electricity, use of a refrigerator, use of an indoor
work area, and disposal costs. This demonstration
generated a 55-gallon drum of laboratory waste. The
appropriate way to dispose of this waste is through an
approved incinerator facility, with an estimated cost of
$2,000 per drum of waste.
Performance Factors
The sensitivity of the FASP PCP Method depends
on the detection limits of the FID and BCD. The
sensitivity of the detectors, especially the BCD, is such
that it always gives some background response; this
response is called "noise level." For most methods that
use gas chromatography, the detection limit is defined as
the minimum amount of a compound that will give a
response greater than three times the noise level of the
instrument. The response of the low PCP standard was
well above three times the noise level for the instrument.
The FASP PCP Method's detection limit depends on
the type of detector used with the instrument. The FID
has a lower sensitivity than the ECD and hence, the
detection limits for the FID are higher than those for the
ECD. The detection limit for soil samples from the
former Koppers site was 0.8 ppm; for soil samples from
the Winona Post site was 1.6 ppm. The detection limit
for water samples, if analyzed using the FID was
0.2 ppm. The ECD was used to analyze water samples
when the FID analysis produced a nondetect. The
detection limit for the ECD was 0.5 ppb PCP. Detection
limits were based on the low PCP calibration standard
used, and the dilution or concentration factors produced
during sample extraction and preparation.
The majority of the soil samples were silty clay to
silty sand. Sodium sulfate was added to all soil samples
to bind the moisture present. Some of the samples from
the Winona Post site contained wood chips. The wood
chips were not segregated before sample extraction. The
operator noted that these matrix characteristics did not
pose a physical problem with the extraction. Samples
from the Winona Post site showed large interferences
from petroleum hydrocarbons. The FASP PCP Method
includes a cleanup step to eliminate contamination from
petroleum hydrocarbons. However, even after extensive
cleanup of the sample extract, the interferences from
petroleum hydrocarbons were not totally eliminated.
The interference from these petroleum hydrocarbons
made the PCP quantitation very difficult. In addition, as
evidenced by the matrix spike recoveries, PCP appeared
to have been lost during these cleanup steps.
Some water samples from the Winona Post site
contained an oil sheen on top of the water layer. The
PCP carrier used at this site was diesel fuel. To reduce
any matrix effects from free-phase petroleum, the pH of
the water samples was increased to greater than 12. The
water sample was then washed one time with MtBE to
remove petroleum hydrocarbons. The MtBE wash was
discarded. The water sample was then acidified to a pH
less than 2.0. The acidified water sample was extracted
with MtBE, and the MtBE extract was analyzed. This
cleanup procedure worked well except for two samples.
Samples 102 and 103, and then* duplicates, showed large
interferences from petroleum hydrocarbons even after
the cleanup steps for petroleum hydrocarbons. These
interferences may be due to inadequate washing of the
water sample with MtBE prior to acidification and
extraction. Additional cleanup may have eliminated this
interference.
Another sample matrix effect was the high levels of
PCP found in many samples. If the initial extract was
analyzed and it produced a detect outside the method
calibration range, the extract was diluted. Of 134 soil
samples, 34 samples were diluted more than 10 fold.
Any tune dilution is attempted, measurement errors may
be introduced.
The FASP PCP Method can use an autosampler to
increase analysis efficiency. The autosampler allows
samples to be analyzed 24 hours a day. Once loaded
with samples, the autosampler can be operated without
the presence of an operator. The FASP PCP Method's
operator observed that up to 20 samples could be
analyzed in each 24-hour period. More than
181 samples were weighed, extracted, cleaned,
concentrated, and analyzed during the 13-day
demonstration period, for an average of 14 samples per
day. The sample throughput was reduced by the time-
consuming cleanup process required for the samples
from the Winona Post site.
The linear range of the analysis for PCP was
established during the ICAL by analyzing the three
different calibrators. The three concentrations used
during the ICAL ranged from 4 to 400 ppb for the FID.
These concentrations correspond to a PCP calibration
range of 0.8 to 80 ppm hi the soil samples. For water
20
-------
samples, the calibration range for the FID was 0.2 to
20 ppm. The PCP calibration range for the ECD was
1 to 50 ppb. Any soil sample that exceeded a PCP
concentration of 80 ppm, and any water sample that
exceeded 20 ppb of PCP was diluted to bring the
response within the calibration range. Forty-eight
samples collected during this demonstration required
dilution to obtain PCP peaks within the linear range of
the calibration. Twenty-three of the samples required a
1:10 dilution; 12 required a 1:100 dilution; 11 required
a 1:1,000 dilution; and two required a 1:10,000 dilution.
The linear range for the FASP PCP Method is
comparable to the linear ranges used hi formal
laboratory analysis.
Drift is a measurement of an instrument's variability
in quantitating a known amount of a standard. The drift
associated with the FASP PCP Method was evaluated
through daily CCALs. The responses exhibited during
the CCALs were compared to those exhibited during the
ICAL. During sample analysis, the retention tune of the
PCP peak was observed to be shifting. The shifts were
small, but they eventually exceeded the acceptable
retention time ranges calculated during the ICAL. The
corrective action for this drift involved establishing new
retention time ranges. The retention times of the PCP
peak for the CCALs were used to establish the new
ranges.
Specificity
Sample interferences may arise due to the presence
of soil organic matter, cocontaminants such as
phthalates, other chlorophenols, and PCP carrier
solvents. Interferences due to PCP carrier solvents are
especially important because they have a strong potential
to give false positive results.
Phthalates, which are common laboratory
contaminants, are found in many of the plastic materials
that can be used in the extraction process. Organic
solvents used to extract PCP will also extract phthalates
from the containers. To prevent such extraction of
phthalates along with PCP, use of plastic materials in
any stage of sample storage, extraction, or analysis is
discouraged. Interferences may also be introduced by
other means, such as carrier gas contamination and
carryover from highly contaminated samples. Potential
for carrier gas contamination is reduced by using ultra-
high purity grade gases. The use of carrier gas filters
also helps eliminate these problems. The extraction and
analysis of highly contaminated samples followed by the
extraction and analysis of less contaminated samples
frequently results in sample carryover contamination.
During this demonstration, sample carryover
contamination was reduced by using disposable
glassware. Glassware was replaced after the extraction
and analysis of each sample. To reduce contamination
of the GC and ECD, only those extracts that the FID
indicated contained no PCP or too little to be detected
were analyzed on the ECD. The use of solvent washes
added to the GC after the analysis of highly
contaminated samples also reduced sample carryover
contamination.
Sample matrix interferences are more difficult to
eliminate. Common manmade sample matrix
interferants include phthalates, halogenated solvents,
halogenated pesticides, polar halogenated compounds,
and chlorinated paraffins. In addition, natural organics
present in soil may affect PCP extraction. Research has
shown that PCP not only adsorbs to soil organic matter
but also forms complexes with humic material. The
FASP PCP Method is based on the belief that adding
acid to bring down the pH to less than or equal to
2.0 will free PCP from such complexes. A concern
raised by EPA Region 7 was that PCP and
pentachlorophenate elute at different times, resulting in
incorrect identification and quantitation. Both of these
compounds can be present at wood treatment facilities.
Acidification of the soil sample should convert all of the
pentachlorophenate ions into PCP.
Cross-reactivity from other phenols was not of
concern, because gas chromatography can identify
specific phenols. However, one problem associated with
high concentrations of other phenols is that such a
sample would require dilution, which would raise the
detection limits for PCP. None of the samples analyzed
during this demonstration contained large amounts of
other phenols.
The major problem associated with PCP quantitation
during this demonstration was interference caused by the
carrier solvent used for PCP application. At the former
Koppers site, PCP was applied to the wood by dissolving
it into isopropyl ether and butane. At the Winona Post
site, diesel fuel was the carrier solvent for PCP
application. The samples from the former Koppers site
did not show any carrier effect. PRC believes this was
due in part to the high volatility of isopropyl ether and
butane. Also, because these carriers elute well before
PCP, they do not cause interference. However, sample
quantitation was affected by the presence of petroleum
hydrocarbons in the Winona Post samples, because PCP
elutes within the petroleum hydrocarbon pattern.
Although the FASP method includes cleanup steps to
eliminate these interferences, interferences were not
removed completely.
21
-------
To evaluate the method for cross-reactivity, the lead
chemist prepared 21 spiked samples. SS-01 through SS-
17 were spiked soil samples, and SS-18 through SS-21
were spiked water samples. Samples SS-01 to SS-04
were spiked with 2,4,6-trichlorophenol; SS-05 to SS-08
were spiked with diesel fuel; SS-10 to SS-13 were spiked
with 2,4-dichlorophenol; SS-14 to SS-17 were spiked
with 2,3,4,6-tetrachlorophenol; and SS-09 was a blank
sample. Water samples SS-18 to SS-21 were spiked
with PCP and diesel fuel. All chlorophenols in soil
samples were spiked at the 5 ppm level; the diesel fuel
was spiked at a SO ppm level hi soil samples; and the
PCP and diesel fuel were spiked in water samples at
50 ppb and 125,000 ppb, respectively.
The FASP PCP Method operator did not identify
PCP hi any of the samples spiked with chlorophenols.
Samples spiked with diesel fuel did give false positive
results for PCP. The mean PCP concentration in these
samples was 2.85 ppm, which indicates that about six
percent of the diesel fuel cnromatograph was identified
as PCP. The mean percent recovery from the samples
spiked with 2,4,6-trichlorophenol was 75 percent.
Similarly, the mean percent recoveries for 2,4-dichloro-
phenol and 2,3,4,6-tetrachlorophenol were 76.8 and
68.8, respectively. This data shows that the method is
capable of separating the phenols. The resultant
recoveries are within control limits. The percent PCP
recoveries hi water samples ranged from 220 to
288 percent. The mean recovery of PCP was
245 percent, and the standard deviation was 30 percent.
The diesel fuel interference is not thought to be the
source of these high recoveries. These samples were
analyzed by BCD, which is specific to halogenated
compounds and should not detect petroleum hydro-
carbons. Currently PRC has not identified the cause of
these elevated recoveries.
Intramethod Assessment
Intramethod measures of the technology's
performance included its results on reagent blanks, the
completeness of its results, its intramethod accuracy, and
its intramethod precision. Reagent blank samples were
prepared by taking reagents through all extraction,
cleanup, and injection steps of the analysis. Reagent
blanks were prepared with each batch of 20 samples.
Ten reagent blanks were prepared and analyzed during
the demonstration: nine reagent blanks for soil analysis
and one reagent blank for water analysis. No PCP was
detected hi any of the blanks above method detection
limits. These results indicate that no laboratory-induced
PCP contamination was present.
None of the FASP PCP Method data was
invalidated, and results were reported for every sample
analyzed. Therefore, the completeness was 100 percent
for soil samples and 100 percent for water samples.
The surrogate standard used for the FASP PCP
Method is 2,4,6-tribromophenol, which like PCP, is a
polar compound. The partitioning of this compound
during the extraction and cleanup process is similar to
the partitioning of PCP. The surrogate was added to all
blanks, samples, their duplicates, matrix spikes, and
matrix spike duplicates at a level of 2 ppm. Surrogate
recoveries were calculated only from the concentrated
sample extract. Whenever the sample extract was not
concentrated or the sample extract was diluted, no
surrogate recoveries were reported. These samples were
coded DL to indicate that the sample was diluted.
In all, 76 surrogate recovery values were obtained
with an average surrogate recovery of 65.8 percent. The
standard deviation of the surrogate recovery was
29.2 percent. Control limits for surrogate standards
were defined as ± 3 standard deviations from the mean.
For the surrogate standards analyzed during this
demonstration, the calculated control limits were from
0 to 153 percent recovery. Two of the 76 surrogate
standard recoveries were outside of these control limits.
No corrective action was taken. These control limits are
advisory limits only. Water samples were also spiked
with 2,4,6-tribromophenol, at a concentration of 1 ppb.
The surrogate recoveries were calculated from data
generated by the FID. The surrogate recoveries from
those samples were diluted and are flagged as DL.
Surrogate recoveries were not calculated from the
ECD data because the surrogate showed a very high
response on the ECD. This response exceeded the
calibration limits of the instrument. In all, 15 surrogate
recovery values were obtained. The average surrogate
recovery was 30.8 percent and the standard deviation
was 13.1. The surrogate recoveries ranged from 0 to
70 percent. Surrogate recoveries of all samples fell
within the established control limits.
Intramethod accuracy was assessed for the FASP
PCP Method by using PE samples and matrix spike and
matrix spike duplicate samples. Five PE samples were
analyzed during the demonstration, two for the soil
matrix and three for the water matrix. Four of them
were purchased from ERA. Water PE sample 113 was
prepared by PRC. These samples were extracted and
analyzed in the same way as the other soil and water
samples. The operator did not know that the samples
were PE samples, nor did the operator know the true
concentrations and acceptance ranges.
The true concentration of soil PE sample 100 (the
high-level sample) was 101 ppm, with an acceptance
22
-------
range of 15 to 177 ppm. The result reported for this
sample by the FASP PCP Method was 94.2 ppm, which
was within the acceptance range. The true value
concentration of soil PE sample 099 (the low-level
sample) was 7.44 ppm, with an acceptance range of
1.1 to 13 ppm. The result reported by the FASP PCP
Method was 4.44 ppm, which also was within the
acceptance range. The true concentration of water PE
sample 107 (the high-level sample) was 2,510 ppb, with
an acceptance range of 377 to 4,420 ppb. The result
reported for this sample by the FASP PCP Method was
1,712 ppb of PCP, which was within the acceptance
range. The true value concentration of water PE sample
106 (the low-level sample) was 68.4 ppb, with an
acceptance range of 10 to 120 ppb. The result reported
by the FASP PCP Method was 78.2 ppb, which was
within the acceptance range. The true value
concentration of water PE sample 113 (the sample
prepared by PRC) was 7.5 ppb, with an acceptance
range of 3.75 to 11.3 ppb. The result reported by the
FASP PCP Method for this sample was 42 ppb, which
was outside the acceptance range. Accuracy of the
samples analyzed by the FASP PCP Method was found
to be 100 percent for soil analysis and 66 percent for
water analysis based on the results of the PE samples.
However, the accuracy for the water analysis could not
have been improved unless all three sample results fell
within the PE sample accuracy ranges.
Matrix spike samples were used to evaluate the
extraction and analysis efficiency of the technology.
They also were used to determine accuracy. Matrix
spike samples were prepared by adding a known quantity
of PCP to a sample. Matrix spike samples were spiked
with PCP at a level of 10.0 ppm in soil samples and
50 ppb in water samples. The spiked sample was also
duplicated to produce a matrix spike duplicate sample.
Recovery results of the matrix spike samples and then-
duplicates are listed in Tables 6-1 and 6-2. Six matrix
spike samples and matrix spike duplicate sample pairs
were extracted and analyzed using the FASP PCP
Method for soil analysis. The recoveries for these
samples ranged from 0 to 89 percent. Matrix spike and
matrix spike duplicate results for sample 058D indicated
0 percent recoveries. The original sample contained
about 3.0 ppm of PCP, which is not high enough to
affect any spike recoveries. These results were excluded
as outliers, and the remaining matrix spike and matrix
spike duplicate pair results were used to evaluate the
technology. The average recovery for these samples was
52 percent. The standard deviation was 39 percent.
Based on this data, control limits for matrix spike
recovery samples ranged from 0 to 130 percent
recovery. All matrix spike samples analyzed fell within
these control limits. One matrix spike and one matrix
spike duplicate sample were analyzed during the analysis
of water samples. These samples were spiked with PCP
at a level of 50 ppb. The sample had an original PCP
concentration of 45.5 ppb. The spike recoveries from
these two samples were 193 and 173 percent. No
statistical evaluation of the data was performed due to
the small size of the data set. The mean recovery
calculated from these two sample recoveries is
183 percent.
For this demonstration, three types of intramethod
precision data was generated: data from laboratory
duplicate samples, data from field duplicate samples, and
data from matrix spike duplicate samples. Laboratory
duplicate samples consist of two analyses performed on
a single sample delivered to a laboratory. Six laboratory
duplicate soil samples and one laboratory duplicate water
sample were analyzed using the FASP PCP Method.
Only samples with detectable levels of PCP were used
for laboratory duplicate analysis. The initial analyses of
the duplicate soil samples ranged from 107 to
9,777 ppm, and the single water sample result was
5,236 ppb. When the analysis was duplicated, the
results ranged from 107 to 4,323 ppm for soil analysis,
and the water sample result was 6,303 ppb. The results
for the soil and water laboratory duplicate samples are
presented in Table 6-3 and Table 6-4, respectively.
Field duplicate samples were also analyzed during this
demonstration. Field duplicates consist of two samples
collected together, but submitted to the laboratory with
separate sample numbers. PRC collected 14 field
duplicate soil samples and 10 field duplicate water
samples during this demonstration. The results for the
soil and water field duplicate samples are presented in
Table 6-5 and Table 6-6, respectively.
Typically, field and laboratory duplicate samples are
used to determine error induced by sample collection and
analysis. Laboratory duplicates are compared to a
window of acceptable values, and if any fall outside that
window, corrective action is taken by the laboratory.
Field duplicates are used to identify sampling analysis
and matrix variability. To control the problems usually
detected by laboratory duplicates, PRC used only one
operator for each technology. It was assumed that any
variance in that operator's laboratory techniques would
be the same for each sample, and therefore, statistically
insignificant. For field duplicates, PRC put each sample
through a homogenization process designed to ensure
that there was little difference between the PCP
concentration in a sample and its duplicate. Only in a
very few samples does the homogenization appear not to
have been complete. Because the samples were
homogenized and because only one operator was used,
PRC used the laboratory and field duplicates together to
determine the technology's precision. There are
20 duplicate pairs for soil analysis and 11 duplicate pairs
23
-------
TABLE 6-1. SOIL MATRIX SPIKE SAMPLE RESULTS FOR THE FASP PCP METHOD
Sample
No.
004
033
046
058D
087D
089
Sample
No.
004
033
046
058D
087D
089
Note:
ND
TABLE
Sample
No.
110D
Sample
No.
110D
Amount Found In
Original Sample
(ppm)
0.82
ND
0.95
3.2
1.78
ND
Amount Added To
Matrix Spike
Duplicate Sample
(ppm)
15.3
9.4
11.8
9.62
9.95
10.6
Amount Added To
Matrix Spike Sample
(ppm)
9.60
10.1
11.5
10.8
10.0
10.2
Amount Found In
Matrix Spike
Duplicate Sample
(ppm)
12.8
8.5
11.5
2.04
10.65
1.84
Amount Found In
Matrix Spike Sample
(ppm)
8.4
9.02
10.8
2.67
6.26
1.44
Percent
Recovery
(%)
78
90
89
0
89
17
Percent
Recovery
(%)
79
89
86
0
45
14
Relative
Percent Difference
(%)
1.3
1,1
3.4
0
66
19
Not detected above soil quantitation limit of 0.80 ppm
6-2. WATER MATRIX SPIKE SAMPLE RESULTS
Amount Found In
Original Sample
(DDb)
45.5
Amount Added To
Matrix Spike
Duplicate Sample
(DPb)
50.0
Amount Added To
Matrix Spike Sample
(DDb)
50.0
Amount Found In
Matrix Spike
Duplicate Sample
(ppb)
132
FOR THE FASP PCP
Amount Found In
Matrix Spike Sample
(DDb)
142
Percent
Recovery
(%)
173
METHOD
Percent
Recovery
(%)
193
Relative
Percent
Difference
(%)
11
Note:
ND Not detected above soil quantitation limit of 0.80 ppm
24
-------
TABLE 6-3. SOIL LABORATORY
DUPLICATE SAMPLE RESULTS FOR THE
FASP PCP METHOD
TABLE 6-4. WATER LABORATORY
DUPLICATE SAMPLE RESULTS FOR THE
FASP PCP METHOD
Laboratory
Original Duplicate Relative
Sample Sample Percent
Sample Result Result Difference
No. (ppm) (ppm) (%)
015 649 339 63
036 40.7 58.9 37
049 501 212 81
059 9,777 4,323 77
072 1,345 1,826 30
084 107 107 0
TABLE 6-5. SOIL FIELD DUPLICATE
SAMPLE RESULTS FOR THE FASP PCP
METHOD
Original Relative
Sample Field Duplicate Percent
Sample Result Sample Result Difference
No. (ppm) (ppm) (%)
001 2.40 2.96 21
011 115 107 7
020 ND ND NA
030 32 40 22
040 11.5 11.8 3
048 29,773 30,464 2
050 1.12 1.84 49
055 1,928 2,580 29
058 30.7 3.2 162
059 9,777 4,731 70
073 59.8 70.7 17
074 486 545 11
086 3.93 3.57 10
087 9.32 1.78 137
Nfttoc*
INLHGO.
ND Not detected above soil quantitation limit of
0.80 ppm.
NA Not applicable due to ND result.
Laboratory
Original Duplicate Relative
Sample Sample Percent
Sample Result Result Difference
No. (ppb) (ppb) (%)
112 5,236 6,303 18
TABLE 6-6. WATER FIELD DUPLICATE
SAMPLE RESULTS FOR THE FASP PCP
METHOD
Field
Original Duplicate Relative
Sample Sample Percent
Sample Result Result Difference
No. (ppb) (DDb) (%)
101 74.5 60.4 21
102 43,804 53,439 20
103 55,900 68,900 21
104 11,307 14,106 22
105 95.1 70 30
108 120 81.3 38
109 89 46 64
110 45 45.5 1
111 11.2 48.7 125
112 5,236 6,288 18
for water analysis. Intramethod precision was evaluated
for each sample matrix using all the duplicate pairs.
Even the best technology that determines results
quantitatively cannot reproduce its results every time.
Therefore, PRC established control limits like those
sometimes used to evaluate laboratory duplicates. These
control limits were then used to determine whether the
difference between a result from a duplicate and the
result from its respective sample was reasonable. To
establish the control limits, all sample pairs that did not
produce two positive results were removed from the data
population. The RPD for each sample pair was then
calculated, and the mean RPD and population standard
deviation were determined. The lower control limit was
set at 0, which means that the results from a duplicate
25
-------
and its sample matched perfectly. The upper control
limit was set by multiplying the standard deviation by
two and adding it to the mean RPD. The RPD of each
sample pair was then compared to these control limits.
Each was expected to fall within them.
The FASP PCP Method detected PCP in both the
sample and its duplicate in 19 of the 20 sample pairs for
soil analysis and in all duplicate pairs for water analysis.
Control limits were established for each sample matrix.
For the soil matrix, the mean RPD was calculated to be
43.6, with a standard deviation of 45.5. Therefore, the
control limits were set at 0 and 135. Two of the sample
duplicate RPDs fell outside the range. The resulting
precision is 89 percent, which is less than the required
90 percent, and thus unacceptable. Similarly, the
control limits for RPDs established for water sample
duplicates ranged from 0 to 102 percent. One RPD was
outside control limits (sample pair 111). This data
shows that 90 percent of the sample RPDs fell within the
control limits, so the precision of the technology was
deemed acceptable for water samples.
Matrix spike duplicate samples were used to further
evaluate the precision of this method. RPD values for
the six sets of soil matrix spike and matrix spike
duplicate samples ranged from 0 to 66 percent. The
mean RPD for these samples was 15 percent, and the
standard deviation was 26 percent. The resultant upper
control limit was 67 percent. All RPD values for the
matrix spike and matrix spike duplicates fell within this
range. Only one matrix spike and matrix spike duplicate
sample was analyzed for water. Based on the small size
of the data set, no control limits were calculated.
However, the RPD value for this sample was 11 percent.
Comparison of Results to Confirmatory
Laboratory Results
PRC used the statistical methods detailed hi Section
3 to determine how well th? 'esults from the FASP PCP
Method matched those from the confirmatory laboratory.
The results used for the various data sets are presented
in Tables 6-7 through 6-9, and a summary of the
statistics is presented in Table 6-10. The purpose of this
statistical data evaluation is to assess whether the method
meets Level 3 criteria for accuracy and precision.
So/7 Samples: Intermethod Accuracy
The initial linear regression analysis on the entire
data set was based on results from 84 samples. The
other results indicated that no PCP was detected above
the method's detection limits. Figure 6-1 illustrates the
comparability between the FASP PCP Method and
confirmatory data. A hypothetical 100 ppm action level
FIGURE 6-1 TOTAL SOIL DATA SET.
:l:
3 -
£
False Positives
-
aj-a.1". '
.".'' T«N«"«~
True Positives .
a f ".V.*
Fabe Negatives
Conlkmitory Laboratory Concentration (ppmj
is also noted on this figure. The r2 for this regression
was 0.35, indicating that little or no relationship exists
between the data sets. However, a residual analysis of
the data identified samples 21, 44, 47, 48, 55, 59, 60,
75, and 76 as outliers. PRC removed these nine points
and recalculated the linear regression. This regression
had an r2 of 0.41, indicating that there is still little
correlation between the two data sets. The Wilcoxon
Signed Ranks Test indicated that the FASP PCP
Method's data was significantly different from that of the
confirmatory laboratory. This supported the regression
analysis. These results indicate that this technology is
not accurate and that it cannot be mathematically
corrected to estimate corresponding confirmatory data.
Based on these results and depending on the intended
data use, all of the samples analyzed by this method may
need confirmation analysis. This places this technology,
for the combined soil data set, into the Level 1 data
quality category.
The second tier of the accuracy evaluation involved
the separation of the data by site. This tier of data
evaluation was conducted to assess potential carrier
effects on the method's performance. Fifty samples
from the former Koppers site were initially used for the
regression analysis. Figure 6-2 illustrates the
comparability between the FASP PCP Method and
confirmatory data. The r2 for this regression was
0.37, indicating that a relationship may exist between
thedata sets. A residual analysis of the data identified
samples 21, 44, 47 and 48 as outliers. PRC removed
these four points and recalculated the linear regression.
When the regression was recalculated on the
46 remaining sample results, it defined an r2 factor of
0.82, indicating that little or no relationship exists
between the two data sets. The Wilcoxon Signed Ranks
Test also indicated, at a 90 percent confidence level, that
the FASP PCP Method's data was not significantly
different from that of the confirmatory laboratory.
Based on these results, 10 to 20 percent of the samples
26
-------
FIGURE 6-2 FORMER KOPPERS SITE SOIL FIGURE 6-3 WINONA POST SOIL SAMPLES.
SAMPLES.
1
5 _
f
o
< 1
Fabe Positive*
1* *
. True Negatives
TruePcxIttve.
False Negatives
Confirmatory Laboratory Conc.ntralion Ippm)
M
£
&
Fate Positives
True Negative*
TfuePosKVea
' '.'**"
f
a
Fab« Negatives
Conlomatory Laboratory Concentration (ppm)
i
analyzed by this method may need confirmation analysis.
This places this technology, for the combined soil data
set, into the Level 1 data quality category.
The second tier of the accuracy evaluation involved
the separation of the data by site. This tier of data
evaluation was conducted to assess potential carrier
effects on the method's performance. Fifty samples
from the former Koppers site were initially used for the
regression analysis. Figure 6-2 illustrates the
comparability between the FASP PCP Method and
confirmatory data. The r2 for this regression was
0.37, indicating that a relationship may exist between
thedata sets. A residual analysis of the data identified
samples 21, 44, 47 and 48 as outliers. PRC removed
these four points and recalculated the linear regression.
When the regression was recalculated on the
46 remaining sample results, it defined an r2 factor of
0.82, indicating that little or no relationship exists
between the two data sets. The Wilcoxon Signed Ranks
Test also indicated, at a 90 percent confidence level, that
the FASP PCP Method's data was not significantly
different from that of the confirmatory laboratory.
Based on these results, 10 to 20 percent of the samples
analyzed by this method need confirmation analysis to
calculate a correction factor, converting the FASP PCP
method's data into estimates of corresponding
confirmatory data. This places this method, for the
Koppers soil data set, into the Level 2 data quality
category.
Thirty-two samples from the Winona Post site were
initially used for the second tier regression analysis.
Figure 6-3 illustrates the comparability of the FASP PCP
Method and confirmatory data. The r2 for this
regression was 0.53, indicating that a relationship may
exist between the data sets. A residual analysis of the
data identified samples 59, 60, 72, and 77 as outliers.
PRC removed these four points and recalculated the
linear regression. The regression then defined an r2
factor of 0.71. This is slightly below the 0.75 required
for Level 2 classification. The Wilcoxon Signed Ranks
Test indicated that the FASP PCP Method's data was
significantly different from that of the confirmatory
laboratory, which supported the findings of the
regression analysis. These results indicate mat this
technology is not accurate, and that it cannot be
mathematically corrected to estimate corresponding
confirmatory data. Depending on the data quality
requirements, all samples analyzed by this technology
may need confirmatory analysis. This factor places this
technology, for the Winona Post soil data set, in the
Level 1 data quality category.
The demonstration results indicate that there is a
carrier effect on this method. The accuracy and
comparability to the confirmatory data is higher in the
samples contaminated with PCP in an isobutyl ether and
butane carrier. The diesel fuel carrier solvent causes
interference that lowers accuracy and comparability with
confirmatory data.
The data was also evaluated by concentration.
Overall, the confirmatory laboratory found that
46 samples had concentrations of less than 100 ppm.
The initial linear regression of these 46 samples defined
an r2 of 0.63, indicating that a relationship may exist
between the two data sets. However, a residual analysis
of the data identified samples 14, 38, 85 and 100 as
outliers. PRC removed these four points, recalculated
the linear regression, and defined an r2 of 0.50, also
indicating that a relationship may exist between the two
data sets. However, the Wilcoxon Signed Ranks Test
indicated, at a 90 percent confidence level, that the
FASP PCP Method's data was not significantly different
from that of the confirmatory laboratory. This
contradicts the regression analysis and indicates that one
of the data sets may not have normal distribution. For
this reason, the regression data was considered suspect.
The results, therefore, indicate that this technology
27
-------
TABLE 6-7. SUMMARY OF DEMONSTRATION DATA: FORMER KOPPERS SITE SOIL SAMPLES
FASP PCP Confirmatory
Method Laboratory
Sample No. (0.80 ppm)a (ppm)
001
001 D
002
003
004
005
006
007
008
009
010
011
011D
012
013
014
015
016
017
018
019
020
020D
021
022
023
024
025
026
052
053
054
055
055D
Notes:
a
b
J
U
2.40
2.96
1.50
<0.80 U
0.82
2.24
1.44
6.00 J
0.31J
2.50
1,100
115
107
<0.80 U
58.2
93.9
649
195
346
5.20 J
5.70 J
<0.80 U
<0.80 U
3,600
17.6
21.6
3.87
521
39.1
29.2
3.67
<0.80 U
1,930
2,580
4.42
4.18
1.64
0.1 3b
2.04
3.70
1.89
2.66
0.66
3.52
435.0
106.0
112.0
0.056b
32.80
99.60
1,190
273.0
1,335
2.13
6.89
0.10
0.09b
5,320
1.85
1.86
1.57
593.0
0.42
28.20
2.23
0.47
3,135
3,003
Sample
No.
027
028
029
030
030D
031
032
033
034
035
036
037
038
039
040
040D
041
042
043
044
045
046
047
048
048D
049
050
050D
051
056
057
058
058D
FASP PCP Confirmatory
Method Laboratory
(0.80 ppm)a (ppm)
11.5
<0.80 U
0.33 J
32.0
40.0
0.58
17.2
<0.80 U
<0.80 U
201
40.7
1.86
107
4.10
11.5
11.8
6.53
4.72
739
17,600
41.0
0.95
127,000
29,800
30,500
501
1.12J
1.84
0.30 J
26.1
9.35
30.7
3.20
11.30
0.45
1.06
28.60
29.00
1.43
0.62b
0.40
0.31 b
145.0
36.80
1.19
77.00
3.32
400.0
34.40
6.44
4.09
655.0
6,956
22.10
0.95
13,920
26,100
30,260
255.0
2.16
1.25
0.43
9.90
8.74
3.53
9.13
Detection limit.
Sample analyzed by Method 81 51 A; all other samples were analyzed by Method 8270A.
Reported amount is below detection limit or not valid by approved QC procedures.
PCP was not detected.
28
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TABLE 6-8. SUMMARY OF DEMONSTRATION DATA: WINONA POST SITE SOIL SAMPLES
Sample
059
059D
060
061
062
063
064
065
066
067
068
069
070
071
072
073
073D
074
074D
075
076
077
078
079
Notes:
a
b
J
U
FASP PCP Confirmatory
Method Laboratory
No. (1 .60 ppm)a (ppm)
9.780
4,730
4.570
457
76.0
219
408
348
32.4
37.4
38.0
664
1,120
249
1,350
59.8
70.7
486
545
860
679
273
361
155
9,600
10,260
1,008
2,744
138.0
1,610
1,978
1,577
57.80
110.0
47.70
798.0
2,888
289.0
336.0
74.80
78.20
836.0
1,520
3.692
4.590
2.040
1,720
792.0
FASP PCP Confirmatory
Sample Method Laboratory
No. (1 .60 ppm)a (ppm)
080
081
082
083
084
085
086
086D
087
087D
088
089
090
091
092
093
094
095
096
097
098
099
100
605
70.0
965
18.6
107
11.5
3.93
3.57
9.32
1.78
<1.60U
<1.60U
<1.60U
<1.60U
0.87 J
<1.60U
<1.60U
<1.60U
18.2
4.16
>1.60U
4.44
94.2
2.550
125.0
2,400
270.0
1,140
57.70
6.59
6.88
34.00
51.80
2.58
0.21 b
0.55b
0.28b
0.57b
0.1 9b
1.02b
0.088b
59.80
14.60
0.57
4.02
52.40
Detection limit; this value was raised due to interference from the diesel fuel carrier.
Sample analyzed by Method 81 51 A; all other samples were analyzed by Method 8270A.
Reported amount is below detected limit or not valid by approved QC procedures.
PCP was hot detected.
meets Level 2 criteria, when analyzing samples with
concentrations of less than 100 ppm, but its data cannot
be mathematically corrected to estimate corresponding
confirmatory data.
The confirmatory laboratory identified 38 samples
with concentrations greater than 100 ppm. The initial
linear regression on these 38 samples defined an r2 of
0.31, indicating that little or no relationship exists
between the two data sets. A residual analysis of the
data identified samples 44, 47, 48, 59 and 60 as outliers.
PRC removed these five points, recalculated the
regression, and defined an r2 of 0.41. The Wilcoxon
Signed Ranks Test indicated that the FASP PCP
Method's data was significantly different from that of the
confirmatory laboratory, which confirmed the regression
analysis. These results indicate that this technology is
not accurate and that it cannot be mathematically
corrected to estimate corresponding confirmatory data.
This factor places this technology, for the combined soil
data set for PCP concentrations above 100 ppm, in the
Level 1 data quality category. The data indicates a
29
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TABLE 6-9. SUMMARY OF DEMONSTRATION
WATER DATA
FASP PCP Confirmatory
Method Laboratory
Sample No.a (0.002 ppm)b (ppm)
101 0.075 0.00414°
102 44 15.90
103 56 13.50
104 11 0.0123
105 0.095 0.849
105D 0.070 0.640
106 0.078 0.0103°
107 4.4 2.050°
108 0.12 0.00185°
108D 0.81 0.00221°
109 0.089 0.000175°
109D 0.046 0.00063°
110 0.045 0.0181°
110D 0.046 0.0181°
111 0.01 1J 0.000348°
111D 0.49 0.00032°
112 5.2 1.810
112D 6.3 2.020
113 0.042 0.00227°
Notes:
a Samples 101 through 105D were from the
Winona Post site; Samples 1 08 through 1 1 2D
were detected from the former Koppers site.
Samples 106, 107 and 113 were PE samples.
b Detection limit
° Sample analyzed by Method 515.1; all other
samples were analyzed by Method 8270A.
J Reported amount is below detection limit or
not valid by approved QC procedures.
trend for the technology to have slightly better accuracy
and comparability when used to analyze samples
containing less than 100 ppm PCP.
TABLE 6-10. SUMMARY OF REGRESSION
AND RESIDUAL STATISTICS SOIL ACCURACY
N r2 Y-int Slope Wilcoxon
Probability
All Data 75 0.41 70.1 0.26 Significant
Difference
All Data 42 0.50 5.3 0.64 No Significant
<100ppm Difference
All Data 33 0.41 116.7 0.34 Significant
>100 ppm Difference
Koppers- 46 0.82 28.4 0.68 No Significant
All Data Difference
Koppers 31 0.76 2.0 1.2 Significant
<100ppm Difference
Koppers 13 0.71 -779.9 1.85 Significant
>100ppm Difference
Winona- 28 0.71 27.4 0.24 Significant
All Data Difference
Winona 9 0.51 -4.64 0.61 Significant
< 1 00 ppm Difference
Winona 19 0.57 84.4 0.23 Significant
>100ppm Difference
Notes:
N Number of data points
r2 Coefficient of determination adjusted for
variance
Y-int Y-axis intercept of the regression line
relationship exists between the two data sets. A residual
analysis of the data identified samples 13, 14, 26, and 38
as outliers. PRC removed these four points, recalculated
the regression, and defined an r2 of 0.76, indicating that
a relationship exists between the two data sets. The
Wilcoxon Signed Ranks Test indicated, at a 90 percent
confidence level, that the FASP PCP Method's data was
significantly different from that of the confirmatory
laboratory. These results indicate that this technology is
not accurate, but that it can be mathematically corrected
to estimate corresponding confirmatory data. Based on
these results, 10 to 20 percent of the samples analyzed
by this method need confirmation analysis. This factor
places this technology, for these samples, in the Level 2
data quality category.
The confirmatory laboratory found that 35 samples
from the former Koppers site had concentrations of less
than 100 ppm. The initial linear regression on these
samples defined an r2 of 0.84, indicating that a
The evaluation of the Koppers data for those
samples the confirmatory laboratory found had results
greater than 100 ppm was based on IS samples. The
initial regression defined an r2 of 0.27, indicating that
30
-------
little or no relationship exists between the two data sets,
but samples 47 and 48 were identified as outliers. PRC
removed these two points, recalculated the regression,
and defined an r2 of 0.71 indicating that a relationship
may exist between the two data sets. The Wilcoxon
Signed Ranks Test confirmed the regression data,
indicating that the FASP PCP Method's data was
significantly different from that of the confirmatory
laboratory. These results, therefore, indicate that this
method is not accurate and cannot be reliably
mathematically corrected to estimate corresponding
confirmatory data. This places the method, for this data
set, in the Level 1 data quality category. This data
indicates that the method tended to have greater accuracy
and comparability to confirmatory data for samples
containing less than 100 ppm PCP.
The same types of analyses were conducted on data
from samples from the Winona Post site. The
confirmatory laboratory found that nine of the samples
had concentrations less than 100 ppm. The initial
regression defined an r2 of 0.51, indicating that a
relationship may exist between the two data sets. A
residual analysis of the data identified no outliers. The
Wilcoxon Signed Ranks Test indicated that the FASP
PCP Method's data was significantly different from that
of the confirmatory laboratory. These results indicate
that this technology is not accurate and that it cannot be
mathematically corrected to estimate corresponding
confirmatory data. This factor places this technology,
for Winona Post site samples with less than 100 ppm
PCP, in the Level 1 data quality category.
The confirmatory laboratory found that 23 samples
from Winona Post site had concentrations greater than
100 ppm PCP. The initial regression defined an r2 of
0.49, indicating that little or no relationship exists
between the two data sets. A residual analysis of the
data identified samples 26, 59, 60 and 80 as outliers.
PRC removed these points, recalculated the regression,
and defined an r2 of 0.57, indicating that a relationship
may exist between the two data sets. The Wilcoxon
Signed Ranks Test verified these results, which indicates
that this technology is not accurate and that it cannot be
mathematically corrected to estimate corresponding
confirmatory data. All samples analyzed by this method
need confirmation analysis. This factor places this
technology, for these samples, in the Level 1 data quality
category. This data indicates a tendency for this method
to be more comparable to the confirmatory data for
samples containing less than 100 ppm PCP. This
conclusion is based on an examination of the slopes and
y-intercepts for the data sets.
So/7 Samples: Intermethod Precision
When the Dunnett's Test compared the RPDs
between the FASP PCP Method's entire field duplicate
data set and the corresponding confirmatory laboratory
data set, the precisions were found to be statistically
similar. When the precision was examined relative to
the site from which the duplicates were collected, the
precision between the methods were found to be
statistically similar at both sites. The Wilcoxon Signed
Rank Test confirmed this conclusion.
Water Samples: Intermethod Accuracy
Nineteen water samples were found to have
concentrations of PCP above detection limits by both the
confirmatory laboratory and FASP methods. These
samples, therefore, were eligible for the regression
analysis. Figure 6-4 illustrates the comparability
between the FASP PCP Method and confirmatory data.
The EPA maximum contaminant level (MCL) of 1 ppb
is also shown on this figure. The r2 for this regression
was 0.92, indicating that a relationship exists between
the data sets. The regression analysis produced a slope
of 3.3, and a y-intercept of 0.36. However, residual
analysis of this data identified samples 102 and 103 as
significantly influencing the regression. When these
points were removed as outliers, the r2 dropped to
0.18 and the slope and intercept changed to 12.0 and
0.76 respectively. This confirmed the strong influence
these points exhibited over the regression analysis. The
Wilcoxon Signed Ranks Test was used to verify these
results. It indicated, at a 90 percent confidence level,
that the FASP PCP method's data was significantly
different from that of the confirmatory laboratory. This
supported the regression analysis. These results indicate
that this technology is not accurate and that its data
FIGURE 6-4 TOTAL WATER DATA SET.
I ,.
!
§ in
t-tMl
M»
1
-.1
,.»,«-.
"
4
TcuaPodlvn
" . .
FatoNegaUvn
Ml t.Hl (.11 M 1 ! 1
Confirmatory Laboratory Concmtntion (ppm)
31
-------
cannot be mathematically corrected to estimate
corresponding confirmatory data. This places the
method, for the combined water data set, in the Level
1 data quality category.
Of these samples, 10 were collected at the former
Koppers site. The r2 for this regression was
0.99, indicating that a strong relationship exists between
the data sets. Figure 6-5 illustrates the comparability
between the FASP PCP Method and confirmatory data.
An examination of the slope (3.0) and y-intercept
(0.042) showed that both of these parameters are not
statistically equivalent to their expected values. The
Wilcoxon Signed Ranks Test was used to verify these
results, but it indicated that the FASP PCP Method's
data was significantly different from that of the
confirmatory laboratory. The method, therefore, does
not produce Level 3 data, but rather Level 2 data. The
data produced from this technology must be corrected to
simulate confirmatory data by submitting 10 to
20 percent of the samples for confirmatory analysis.
Six of the 19 water samples eligible for regression
analysis were from Winona Post site. The r2 for
regression on these six samples was 0.87, indicating that
a strong relationship exists between the data sets. Figure
6-6 illustrates the comparability between the FASP PCP
Method and confirmatory data. An examination of the
slope (3.2) and y-intercept (2.2) showed that both of
these parameters are not statistically equivalent to their
expected values. A residual analysis of this data,
though, showed that samples 102 and 103 had a large
influence on the regression, and when these outliers
were removed and the regression was recalculated, the
r2 was zero.
The Wilcoxon Signed Ranks Test, however,
indicated at a 90 percent confidence level that the FASP
PCP Method's data was not significantly different from
that of the confirmatory laboratory, without the outliers.
The regression analysis, therefore, did not agree with the
Wilcoxon Signed Ranks test when it was run on the data
set without the outliers. This indicates that the condition
of normality was not satisfied by one or both of the data
sets, and it makes the regression analysis suspect. This
indicates that the technology does not produce Level
3 data but rather Level 2 data. Data produced from this
technology is statistically similar to confirmatory data
FIGURE 6-5 FORMER KOPPERS SITE
WATER SAMPLES.
|:
1"
:.
_ a
Fall* Poilttft*
Ttut N*gtfh*i
, Tiue Positives
False Negatives
Confemalory L«bot»lOfy Concmtotion (ppm|
FIGURE 6-6 WINONA POST WATER
SAMPLES.
it*
I
I "
» '"
«.«**!
t*
-
1
U.
Tft» NcaaBvvi
*
True Positives
False Negatives
Ml I.MI l.«l *.l 1 II 1
M
CootlimaKxy Laboritoty Concanlration (ppm)
but cannot be corrected. This data indicated that the
method is affected by PCP carrier interferences. This
method produced the greatest accuracy and
comparability to confirmatory data for PCP in an
isobutyl ether and butane carrier.
Water Samples: Intermethod Precision
For water sample analysis, the Dunnett's Test
compared RPDs between the FASP PCP Method's field
duplicate data set and the corresponding confirmatory
laboratory data set. This indicates that the technology's
precision is not different from the confirmatory
laboratory's. The Wilcoxon Signed Rank Test
confirmed this data.
32
-------
Section 7
Applications Assessment
The principal advantage of the FASP PCP Method
is that it is very specific to PCP. This specificity
reduces the chances of determining that a sample
contains PCP when, in fact, it does not. This specificity
also greatly reduces the chances of determining that a
sample contains no PCP, when it actually does. Other
advantages of the FASP PCP Method include the
following: (1) it is inexpensive when compared to
formal laboratory analysis using EPA-approved methods
for PCP, (2) it is portable enough to use in the field,
(3) it has a high sample throughput, and (4) it is capable
of providing sample results quickly. In addition, the
detection limit for water samples analyzed with the
FASP PCP Method is less than the MCL of 1.0 ppb.
The MCL is an EPA-enforceable action limit for PCP in
water samples.
The FASP PCP Method provides quantitative
estimates of PCP concentrations in soil and water
samples. It estimates sample results through a
quantitative comparison to a standard curve. However,
its estimation of PCP concentrations in samples may not
always agree with results from the analysis of the same
sample by EPA-approved methodologies. The results
from this demonstration indicate that this technology has
a carrier solvent sensitivity. The technology produced
data that were more consistent with confirmatory results
for samples from the former Koppers site. The high
level of diesel fuel contamination in the Winona Post site
samples required extensive cleanup steps to remove in-
terferences. These cleanup steps were not sufficient to
remove all of the interferences. Thus, the Winona Post
site results were all significantly different than the
confirmatory results. Method results, when compared to
confirmatory laboratory results, may include both false
positive results, which overestimate the concentration of
PCP in the sample, and false negative results, which
underestimate the concentration of PCP in the sample.
Both false positive and false negative results have
important implications on investigative and remedial
activities. Another limitation of the FASP PCP Method
is that it can be affected by chemicals found naturally in
environmental samples, such as humic acids, as well as
by chemicals associated with PCP treatment of wood
products. These chemicals may affect the technology's
performance even when cleanup steps are employed.
The FASP PCP Method is best operated by
individuals with at least 6 months of experience using a
GC and at least 1 month of experience performing PCP
analysis. Logistical limitations of the FASP PCP
Method include the need for a large capital investment
for the purchase of the analytical instrumentation and
extraction equipment. This equipment may also be
rented. The FASP PCP Method's equipment requires
electricity for operation, and the instruments must be
operated indoors in a temperature-controlled
environment. The method uses hazardous chemicals
such as MtBE, sodium hydroxide, and sulfuric acid.
Proper safety and disposal practices need to be employed
when using the FASP PCP Method.
The FASP PCP Method is designed to provide
quantitative screening results for PCP in water and soil
samples. Applications for the FASP PCP Method
include both laboratory and field uses. The FASP PCP
Method can be used by laboratories as a rapid screening
tool for PCP. Its results can be used to determine
appropriate sample extraction techniques as well as to
determine dilutions mat may be required for sample
analysis. Its results also can be used to determine the
appropriate analytical method to be used for
confirmatory sample analysis. The use of this method in
this mode can protect more sensitive instruments from
damage exposure resulting from highly contaminated
samples. The FASP PCP Method also can be used to
guide the following field investigations and sample
collection activities: (1) determining the vertical and
horizontal extent of PCP contamination in soil,
(2) tracking PCP groundwater contamination plumes,
and (3) determining PCP contamination in surface
waters. Another use of the FASP PCP Method is to
monitor the effectiveness of remediation techniques
employed to reduce or eliminate PCP contamination. In
33
-------
particular, it can be used to determine whether PCP
concentrations in soil or water samples exceed
site-specific action limits.
The FASP PCP Method is best used at sites where
PCP is a known contaminant, where petroleum products
are not the carrier solvents, and where large
concentrations of other organic chemicals are not present
in the samples. Generally, the larger the site or the
larger the number of samples collected, the greater the
advantage of using the FASP PCP Method. The use of
this method at large sites will decrease the cost of the
investigation by decreasing the number of samples
requiring confirmatory laboratory analysis and by
enabling more work to be completed during a single
sampling visit. The primary advantage of this method is
that it can allow work to continue without having to wait
for confirmatory laboratory results.
The technology can be used to guide field work and
sampling efforts, provided that at least 10 to 20 percent
of the samples are submitted to a confirmatory
laboratory for EPA-approved method analysis. These
samples must constitute PCP concentrations from all
levels found. Results from the confirmatory laboratory
can be used to formulate correction factors for the
technology's results or verify its similarity to the
confirmatory data. Correction factors, if needed, can be
applied to its results to obtain a more precise estimation
of PCP contamination. Correction factors are site
specific and may, hi fact, be sample-matrix specific.
Any time sites or sample matrices change, new
correction factors should be established by comparing
the FASP PCP Method's results to confirmatory
laboratory results of the same samples.
Particular attention needs to be paid to samples with
PCP concentrations near the action limit of the site,
because the method can provide both false positive
results and false negative results when compared to
confirmatory laboratory results. False positive results
will cause remediation efforts to be performed hi areas
that do not require cleaunup. False negative results will
cause no remediation to take place hi areas where
cleanup is needed. To limit the impact of false negative
results, working action levels for this method should be
set at 80 to 90 percent of the target action level. Field
investigators should recognize that the FASP PCP
Method is designed as a screening tool to assist hi
evaluating PCP contamination. The technology is an
abbreviation of an approved method for determining
PCP concentrations. When in doubt, samples should be
submitted for confirmatory laboratory analysis using
EPA-approved methods.
34
-------
Section 8
References
PRC Environmental Management, Inc. (PRC). 1993a. "Predemonstration Sampling Plan For The Evaluation of
Pentachlorophenol Field Screening Technologies." EPA Contract 68-C00047.
PRC. 1993b. "Final Demonstration Plan for the Evaluation of Pentachlorophenol Field Screening Technologies."
EPA Contract No. 68-CO-0047.
Stanley, T. W. and S. S. Verner. 1983. "Interim Guidelines and Specifications for Preparing Quality Assurance
Project Plans." U.S. Environmental Protection Agency, Washington DC. EPA/600/4-83/004.
U.S. Environmental Protection Agency. 1990. "Quality Assurance/Quality Control Guidance for Removal
Activities." EPA/540/G-90/004. April.
oc
*U.S. GOVERNMENT PRINTING OFFICE: 1995-653-336
------- |