United States
Environmental Protection
Agency
Environmental Sciences Division March 1999
P.O. Box 93478
Las Vegas, NV 89193-3478
OFFICE OF RESEARCH AND DEVELOPMENT
TECHNOLOGY SUPPORT PROJECT
v>EPA Guidance for
Characterizing
Heterogeneous
Hazardous Wastes
Introduction
Planning the Study
QA/QC and Data
Quality Assessment
Sample Acquisition
The U.S. EPA and the U.S. DOE
are interested in addressing the
special problems presented in
sampling heterogeneous
hazardous waste ranging from
physically diverse samples from
landfills to chemically mixed waste
found at many sites. This area of
sampling and analysis poses
problems to field and laboratory
personnel engaged in the
identification, classification and
quantitation of potentially
hazardous materials.
A recent workshop cosponsored
by the DOE Office of Technology
Development and the
Environmental Sciences Division
(ESD) in Las Vegas resulted in a
document that provides guidance
for scientists working in this
challenging area. Characterizing
Heterogeneous Hazardous
Wastes: Methods and
Recommendations (EPA 600/R-
92/033) is available to Agency
personnel through CERI. This
document contains valuable
information about proven
protocols as well as innovative
technologies and
recommendations for further
research. It presents a typical
case study and a survey of the
statistics involved in design and
analysis.
This chapter establishes a ra-
tional diagram to follow in the
sampling and analysis scheme. It
is a five-step process: prelim-inary
planning, DQO process, sampling
and analysis design, sample
collection and analysis, and data
assessment. Sam-pling
heterogeneous matrices is
complex and presents a challenge
to those planning the study.
Particular stress is placed on
asking the right questions at the
beginning of a study, searching for
any pertinent historical data, and
establishing DQOs that are
realistic. Examples are provided
that prompt readers to look for
potential pitfalls in a sampling
scheme. Guidance is provided for
the use of nontraditional statistical
sampling plans and
recommendations are made for
the establishment of appropriate
confidence intervals.
In this chapter, the focus is on
quality assessment strategies that
can be used in the sampling of
heterogeneous matrices and in
the analysis of the subsequent
data. The importance of a priori
knowledge is stressed. An
effective quality assessment
process will provide useable data
without stipulating onerous
procedures upon the already
overworked sampling expert. The
correct use of QA/QC samples
such as replicates, duplicates,
and colocated samples is
discussed. Field evaluation
samples and field matrix spikes
are recommended. Even in
unconventional methods, the use
of well-planned QA/QC practices
can identify random or biased
error and trace the error to its
source.
The reader is referred to the
document A Rationale for the
Assessment of Errors in the
Sampling of Soils (EPA/600/4-
90/013) and to the software
package, ASSESS, available
through CERI to Agency users.
This chapter specifies sampling
procedures that should be
followed when sampling
heterogeneous hazardous waste
- whether contained or
uncontained. Contained waste is
that found in drums or boxes.
Uncontained waste is landfill litter
and debris piles that exist at some
sites. The monitoring of regulated
landfills is required by law.
Sometimes state monitoring
requirements are more rigorous
than federal guidelines.
Several questions arise when
sampling heterogeneous waste.
Is it possible to obtain a sample of
sufficient representativeness that
the resultant data will truly reflect
the type and level of
contamination at the site? Is it
correct to physically separate
samples before analysis? Should
this separation be based on
physical characteristics or on
contamination type? How can
health risks be fairly evaluated
when the contamination varies in
level from trace to high
percentages? Can homogeni-
zation steps be taken without
compromising the quality of the
data? These questions are
addressed and guidance is given
in technologies ranging from soil-
gas measurement and open-path
FTIR to geophysical methods and
197CMB98.FS-16
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Sample Acquisition
Continued
Analytical
Laboratory
Requirements
For Further
Information
aerial photography. Particular
emphasis is placed on sample
collection procedures and on
handling steps. Field screening
methods are discussed: x-ray
fluorescence, vapor analyzers,
and various spectroscopic tech-
niques. Additional discussion
focuses on radiography, gamma
ray assay, and neutron assay
methods.
This chapter deals with the
analysis of the samples as they
are received by the analytical
laboratory. If the sample arrives
as a multiphase liquid or as a
collection of various solids,
decisions must be made about
the analysis. It is crucial that any
segregation or homogenization of
samples be discussed with the
decision makers. The DQOs
should be consulted again and, as
always, QA/QC plays a vital role
in the generation of useable data.
A flow chart is provided to lead
the reader through several phases
of the laboratory procedure. The
consideration of a priori
knowledge is important in the
laboratory, too.
Fusion methods are discussed for
use in the analysis of inorganic
contaminants. Neutron activation
analysis is suggested for some
analyses of radioactive samples.
Guidance is provided on the
choice of sample size and the
consideration of particle size. A
table compares various radiation
screening devices.
A section on the special
requirements of mixed waste
samples documents the need for
further refinement of analytical
methods and the need for proper
safety precautions. Waste
disposal at the analytical
laboratory is discussed and the
reader is reminded that help
exists in this area from the
American Chemical Society's Task
Force on RCRA.
The importance of proper
reporting is stressed because the
need for understanding reporting
requirements in advance is often
critical in the success of a study.
For further information about the document, Characterizing Heterogeneous Hazardous Waste: Methods and
Recommendations (EPA/600/R-92/003) or to obtain a copy, contact:
Mr. J. Gareth Pearson, Director
Technology Support Center
U.S. Environmental Protection Agency
National Exposure Research Laboratory
Environmental Sciences Division
P.O. Box 93478
Las Vegas, NV 89193-3478
Phone: (702)798-2270
Fax: (702)798-3146
The Technology Support Center fact sheet series is developed and written by Clare L Gerlach, Lockheed
Martin, Las Vegas.
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