United States
Environmental Protection
Agency
Environmental Monitoring
Systems Laboratory
Las Vegas NV89114
Research and Development
EPA-600/S4-84-028 May 1984
&EPA Project Summary
Multielemental Analytical
Techniques for Hazardous
Waste Analysis: The State-of-
the-Art
T.A. Hinners, J.A. Oppenheimer, A.D. Eaton, and L.Y.C. Leong
Based on a comprehensive review of
the literature, the multielemental tech-
niques of inductively coupled plasma
optical emission spectroscopy (ICP), x-
ray fluorescence spectroscopy (XRF)
and instrumental neutron activation
analysis (INAA) have been compared
for the determination of antimony,
arsenic, barium, beryllium, cadmium,
chromium, copper, lead, mercury,
nickel, selenium, silver, thallium and
zinc in hazardous waste matrices.
These particular elements were chosen
because they are on the list for classifying
a waste as hazardous and/or on the
U.S. Environmental Protection Agency's
(EPA's) Priority Pollutant list. Each
technique is discussed with respect to
theory, anticipated interferences and
correction techniques, observed pre-
cision and accuracy for simple and
complex matrices, detection limits, and
cost.
The literature review revealed that
there has not been sufficient analytical
work on complex matrices to fully
compare these three techniques for
many of the priority pollutant elements.
For those elements with a sufficient
database to compare precision and
accuracy by the three techniques
(arsenic, barium, chromium, lead,
nickel and zinc) ICP offers an advantage
in detection limits and precision,
whereas XRF may be very useful as a
preliminary screening technique due to
its ability to provide rapid, semi-quanti-
tative data even at trace levels. XR F and
ICP have significant cost advantages
over INAA, requiring much less capital
expenditure and lower labor costs.
This Project Summary was developed
by EPA's Environmental Monitoring
Systems Laboratory, Las Vegas, NV, to
announce key findings of the research
project that is fully documented in a
separate report of the same title (see
Project Report ordering information at
back).
Introduction
Information on the pollutant content of
wastes is required to properly assess the
hazard and the need for waste manage-
ment or for remedial action. Multielemental
analytical techniques are attractive as the
means to obtain inorganic content
information on wastes rapidly and/or
economically. Although multielemental
techniques are widely used, complex
wastes and contaminated soil present the
potential for interferences not normally
encountered. The elements antimony
(Sb), arsenic (As), barium (Ba), beryllium
(Be), cadmium (Cd), chromium (Cr),
copper (Cu), lead (Pb), mercury (Hg),
nickel (Ni), selenium (Se), silver (Ag),
thallium (Tl) and zinc (Zn) are identified in
federal publications as pollutants of
special concern.
The present work is a literature
evaluation of currently available multi-
elemental techniques in ordertocompare
the advantages and limitations for the
analysis of the specified elements in
hazardous wastes or in contaminated
soils. The currently available multiele-
mental techniques for trace element
-------
determinations are isotope dilution mass
spectrometry, spark source mass spectro-
metry, multielemental atomic absorption
spectroscopy, voltammetry, inductively
coupled plasma optical emission spectro-
scopy, instrumental neutron activation
analysis, and x-ray fluorescence spectro-
scopy. Each technique was evaluated in
terms of accuracy, precision, detection
limits, severity of matrix interferences
and economic factors.
Procedure
A preliminary evaluation was conducted
to select the most promising techniques
for an extensive literature search and a
survey of users. A thorough literature
search was accomplished with the
assistance of the Lockheed computer
system DIALOG which enables the user
to search selected abstract files. The files
searched included Chemical Abstracts,
National Technical Information Service
(NTIS), Compendex (collection of engineer-
ing journals), Agricola (collection of
agricultural journals). Foundation Grants
Index, Dissertation Abstracts, Enviroline
(collection of environmentally oriented
journals), Scisearch, Pollution Abstracts,
SSIE Current Research, and Conference
Papers Index. More than 50 different
journals and abstracts were searched.
Any publication which provided informa-
tion on detection limits, precision or
accuracy for any of the selected elements
was included in the data set. This was
accomplished with the aid of the computer
system Datatrieve on the VAX 11 /780
computer. In addition, a questionnaire
was sent out to users of the various
techniques to solicit the most recent
information.
Finally, an assessment and comparison
of the most promising techniques for
analyzing hazardous wastes was con-
ducted with respect to analytical capabili-
ties and limitations, detection limits,
precision, accuracy, complexity of sample
preparation, availability of commercial
services and cost.
Results and Discussion
Table 1 summarizes the advantages
and disadvantages of each of the potential
analytical techniques. Isotope dilution
mass spectrometry and spark source
mass spectrometry possess unacceptable
economic factors of large capital cost,
expensive labor costs, and lengthy
analysis time. Multielemental atomic
absorption spectroscopy is not currently
available commercially, and has not been
fully investigated. Voltammetry lacks
sufficient selectively to be developed as a
Table 1 . Comparison Summary of Multielemental Techniques (+ = advantage. - = disadvantage)
Technique
Property
MAAS AAS ICP XRF INAA IDMS SSMS VM
Minimal Operator Skill Required
Cost
Detection Limits
Freedom from Interferences
Precision
Availability
Working Range
Large Number of Elements
Analysis Time
MAAS = Multielemental Atomic Absorption Spectroscopy.
AAS =Atomic Absorption Spectroscopy.
ICP =lnductively Coupled Plasma Optical Emission Spectroscopy.
XRF =X-Ray Fluorescence Spectroscopy.
INAA = Instrumental Neutron Activation Analysis.
IDMS =Isotope Dilution Mass Spectrometry.
SSMS = Spark Source Mass Spectrometry.
VM = Voltammetry.
method for routine multielemental analy-
ses of complicated matrices. ICP, INAA
and XRF were judged to be the most
promising multielemental methods for
the determination of the specified ele-
ments in hazardous wastes.
The numerical results of the literature
search are summarized by element and
technique in Table 2. A minimal amount
of data was found for x-ray fluorescence
determination of Ag, Cd, Sb, Hg, Se and
Tl. XRF has traditionally been used for
determining major elements and this
explains the paucity of data for these
elements, which typically occur at fairly
low concentrations in environmental
samples. For neutron activation there is a
minimal amount of data available on Be,
Pb and Tl because these elements do not
possess isotopes with adequate reaction
cross-sections to form sufficient gamma-
emitting radio-nuclides. For ICP, little data
are available for Hg or Tl because these
elements can be determined to lower
Table 2. Number of Records in the Litera-
ture by Element and Technique
Technique
Element
Ag
As
Ba
Be
Cd
Cr
Cu
Hg
Ni
Pb
Sb
Se
Tl
Zn
ICP
34
50
87
55
no
137
198
9
149
166
27
27
7
164
INAA
10
18
53
1
15
54
12
18
34
6
31
18
0
35
XRF
1
11
82
0
7
96
66
4
116
56
1
3
0
78
Total
45
79
222
56
132
287
276
31
299
228
59
48
7
277
concentrations using cold-vapor AAS and
furnace AAS, respectively; and few
standard reference materials have these
elements present at concentrations
measurable by ICP. Information entries
on the specified elements number 1220
for ICP, 521 for XRF and 305 for INAA.
Inductively Coupled Plasma
Optical Emission Spectroscopy
(ICP)
Inductively coupled plasma is a form of
optical emission spectroscopy that utilizes
an argon plasma as the excitation source.
Optical emission spectroscopy is a
technique that involves heating a sample
in a flame, electric arc, electric spark or
plasma to produce a population of excited
atoms and ions that return to the ground
state by emitting radiation. Each element
emits light of a characteristic wavelength,
and signal response is proportional to
concentration level.
Accuracy is affected by a number of
potential sources of -error. Analytical
errors in ICP are caused by direct spectral
and background interferences due to
matrix elements, sample interaction
with the plasma, variable physical
characteristics of different matrices and
instrumental drift. Accuracy is assessed
by examining percent recoveries for
analytes added to samples or by agree-
ment with certified values for reference
materials, such as Standard Reference
Materials (SRMs) from the National
Bureau of Standards. For 12 of the 14
elements there are sufficient data
available to make some assessments for
determinations by ICP. For Hg and Tl
there are no available data on precision
and accuracy. This is principally because
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Hg and Tl are usually determined with far
greater sensitivity using cold-vapor AAS
and furnace AAS, respectively. In addition,
there are no SRMs with certified values
for Hg or Tl at levels measurable by ICP.
The ICP instrumental analysis rate is
typically 30-100 samples per day. The
rate-limiting step for analysis of solid
samples is the required preliminary
digestion to provide a liquid for introduc-
tion into the instrument. Although the
digestion can be set up for batches of 50-
100 samples, the overall digestion time
for these samples is several hours. Many
laboratories offer ICP analysis at rates
ranging from $20-$100/sample, depend-
ing on the number of elements being
analyzed and the complexity of the
sample preparation.
Capital Investment (ICP)
$50K (Basic ICP) Add $10K for sampler
and printer
S100K (ICP/AAS full system - Monochro-
mator or 20 channel Simultaneous
ICP)
$175K (Top-of-the-Line Simultaneous
ICP with scanning capacity and 40
channels).
Instrumental Neutron
Activation Analysis (INAA)
Instrumental neutron activation analy-
sis is a nuclear technique in which the
sample is exposed to a neutron flux and
the induced radioactivity is determined
using gamma ray spectrometry. Charac-
terization and measurement of the
energy of the emitted gamma rays yields
qualitative and quantitative analysis of the
sample. The advantages of this technique
are its nondestructive nature, minimum
sample manipulation requirements and
low detection limits. The main limitations
are matrix interferences, required access
to a neutron source (with associated high
capital costs), the fact that not all
elements are amenable to this type of
analysis, and the possibilitythat the small
solid specimen which is analyzed may not
be homogeneous and representative of
the bulk sample.
In multielemental analysis by INAA,
detection limits must be sacrificed some-
times in order to avoid serious interferen-
ces with the other elements being deter-
mined and the major matrix constituents.
Beryllium cannot be analyzed by INAA
because it forms no gamma-emitting
radionuclide. Only one gamma-emitting
nuclide exists for Pb and for Tl, and the
very low reaction cross-section for these
nuclides implies poor detection limits for
> Pb and Tl by INAA.
Analytical errors in INAA occur when
factors affecting the formation of the
radioactive isotope or detection of the
emitted radiation differ significantly
between the sample and the standard.
Formation of the radioactive isotope is
dependent on the neutron flux density,
the number of target nuclei, and the
reaction cross-section. The number of
target nuclei and the reaction cross-
section are intrinsic properties of the
sample, and variations in the flux density
hitting samples and standards are trivial
due to constant rotation of the specimens
within the reactor. The detection of the
emitted gamma-rays is primarily a
potential source of error. The accuracy of
the total photopeak count must be
corrected for systematic errors arising
from spectral interferences, peak-broaden-
ing errors, absorption errors, and instru-
ment dead-time losses. Random errors
result from counting statistics and
procedural uncertainties.
Using several irradiations for different
periods and counting after different decay
periods eliminate many potential sources
of error. Different irradiation times allow
the analyst to obtain data for short-lived
isotopes without generating high specific
activity from longer lived isotopes (with
a potential for large dead-time correc-
tions). Alternate decay periods make it
easy to resolve peaks of similar energy
but different half-lives. Sophisticated
computer software is essential for
performing these corrections.
Precision improves with increasing
concentration for INAA while the accuracy
is excellent for the high levels but poor for
some of the elements at low levels (<10
yug/g). No INAA data were reported for Ag,
possibly because its INAA detection limit
near 1 fjg/g is comparable to, or larger
than, the level in most terrestrial materials
used as SRMs. The precision exceeds
20% for As at 10/yg/g, for Ba at 10O^g/g,
for Cr at 10yug/g, for Ni at 100//g/g, and
for Sb at <1 yug/g. The poor Ni precision
probably reflects measurements with
reactors having few fast neutrons, while
Ba suffers from Fe interference. The
accuracy exceeds the arbitrary acceptance
criterion of 100 ± 20% recovery at, and
below, a level of 10/yg/g for Cd, 10/t/g/g
forCr, <1 /yg/gfor Hg, 10/yg/gforNi, and
10 fjg/g for Sb.
INAA involves no elaborate sample
preparation procedures. Solids are
ground, and a representative aliquot is
mixed with cellulose and pressed into a
standard size pill. Dissolved material in
liquids can be analyzed after freeze drying
and pallatizing the resulting powder.
Chromium contamination at the level of
0.5 jug/g sometimes results from the tool-
steel dies used to prepare the pellets.
The rate limiting step is the time
required before interfering radiation has
decayed sufficiently to allow long-lived
isotopes to be counted. This can be as
long as 30 days for the analysis of long
half-life isotopes such as Cr51. Throughput
can also depend on the cross-sections of
matrix interferents as well as the half-life
of the element of interest. If matrix
elements become highly radioactive, it
may be difficult to detect the small
amount of radiation emitted by a trace
element. In this case, provided the
interferents have shorter half-lives than
the elements of interest, it is necessary to
wait until the interfering radiation has
decayed away before counting the
sample.
Typical cost for single-sample multiele-
mental analysis is $400 with delivery
times of 5-6 weeks after receipt of
sample. Availability of commercial ser-
vices is quite limited because of the
difficulties in acquiring access to a
nuclear reactor. Services which use
university reactors are available, but
typically only on a research basis and not
for routine analyses. It is possible to
perform INAA using a radioactive element
as a neutron source (such as Cf25"), but
the flux obtained from such a source is
typically not adequate for trace level
work.
Capital Investment (INAA)
$500K
(requires permit)
S135K and up
depending on
required length
of irradiation,
sample size,
and neutron flux
$30K and up
Nuclear Reactor (or
access to irradiation
source)
Commercial Irradia-
tion Cost (for short-
lived isotopes, the
detector must be at
the irradiation site)
Gamma-Ray Spec-
trometer and Detec-
tor
X-ray Fluorescence
X-ray fluorescence is a form of spectro-
scopy in which a sample is bombarded
with x-rays and inner-orbital electrons
are ejected from atoms within the
sample. The resulting excited atoms
dissipate energy by filling these vacancies
with electrons from higher energy levels
and emitting characteristic x-ray photons.
This secondary emission of x-rays is
referred to as fluorescence and, because
only certain emissions occur, the x-ray
spectral lines are indicative of the
elements present. Element concentra-
tions are deduced from the x-ray count
-------
rate of a characteristic line. The advan-
tages of this technique are basically the
same as those of neutron activation
analysis. XRF is nondestructive, allows
for direct analysis of solid samples, and
exhibits useful detection limits. Disad-
vantages of this technique are the
severity of matrix effects, difficulty in
analyzing liquid samples directly, and the
fact that elements with atomic numbers
less than 10 cannot be determined with
conventional instrumentation.
In XRF a significant portion of the
secondary and primary x-rays is absorbed
by the major constituents comprising the
sample matrix. The key to obtaining
reliable x-ray fluorescence data is proper
sample preparation. The sample must be
prepared in a manner which will minimize
matrix absorption problems and also
ensure homogeneity (which is important
because incident x-rays do not penetrate
far into the sample). Conversion of x-ray
count rate to element concentration will
not be accurate unless the sample mass
absorption effects can be compensated
for or eliminated. Interferences which
can occur in addition to matrix absorption
are direct spectral interferences, back-
ground radiation interferences, and self-
absorption of fluorescent radiation.
XRF precision does not often drop
below the arbitrary acceptance value of
20% for the relative standard deviation
until the concentration is greater than 10
/jg/g and, in some cases (Ba, Cr, Ni), not
until the concentration is greater than
100/yg/g. Barium and chromium, along
with Pb, arealsotheelementsthatexhibit
poor accuracy at lower concentrations.
Commercial analysis costs range $5-
$100 per sample depending upon the
quantity of samples and the complexity of
the analyses. No commercial services
offer analysis for the 13 listed elements
(excluding Be) that are measurable; by
conventional XRF instruments. The
availability of commercial XRF services is
much more limited than for ICP.
Capital Investment (XRF)
$75-85K (Energy Dispersive) add $15-
20K for sampler
$95K (Wavelength Dispersive, sequen-
tial)
$125K (Wavelength Dispersive - more
intensity)
$350K (Wavelength Dispersive, Simul-
taneous, Deluxe)
Comparison of ICP, INAA
and XRF Techniques
ICP is the only technique, among the
three, capable of analyzing all of the 14
specified pollutant elements. Beryllium
cannot be determined by INAA (because
its radionuclide emits no gammas) nor by
conventional XRF (because the long
wavelengths of the emitted x-rays cannot
be dispersed). Pb and Tl are too weakly
activated to be successfully determined
by INAA, except at very high concentra-
tions. The lack of a substantial database
for XRF analysis of trace elements
reflects the trend for it to be used most
frequently as a major element technique.
Table 3 ranks these three techniques for
eight characteristics. Table 4 shows the
median detection limit for each element
as a function of instrumental technique.
A comparison of the accuracy and
precision for the three techniques was
obtained by using data for rock, sediment,
soil, sludge, coal, oil, steel, and pottery.
The comparison was made by calculating
the percentage of sample data where
recovery (accuracy) exceeded an arbitrary
criterion of 100 ± 20% and where the
relative standard deviation (precision)
exceeded an arbitrary criterion of 20%.
The results of these calculations are
shown in Tables 5 and 6.
For some of the elements, insufficient
data were available for all three tech-
niques, and a valid comparison could not be
made. This is the case for the precision
data on Ag, Be, Cd, Hg, Pb, Sb, Se, and Tl.
In terms of precision, ICP appears to yield
the best results for almost all the
remaining elements. ForZn the precision
differences among the three techniques
are insignificant. Cu has insufficient data
by INAA to allow a comparison. For XRF
and INAA, there are only sufficient data
for comparison of As, Ba, Cr, Ni, and Zn.
Table 6 shows that these two techniques
give approximately the same criterion
percentages for As, Ba, Cr and Zn while Ni
results are better by XRF than by INAA.
Inspection of theaccuracydata indicates
insufficient information for Ag, Be, Hg,
Sb, Se, and Tl. Of the eight remaining
elements, ICP gives the best results for
Cd, Cr, Cu and Ni. ForXRFandINAAthere
are insufficient data for comparison of As.
INAA gives better results for Ba, and XRF
Table 4. Comparison of Median Detection
Limits f/jg/gl for the Selected Ele-
ments as a Function of Instru-
mental Technique
Technique
Element
ICP*
XRF INAA
Ag
As
Ba
Be
Cd
Cr
Cu
Hg
Ni
Pb
Sb
Se
Tl
Zn
0.3
3
0.05
0.05
0.2
0.3
0.2
3
0.8
2
3
2
2
2
—
0.9
JO
—
5
1
1
2
1
2
—
13
—
3
J
0.2
53
—
15
2
6
0.3
160"
—
0.08
0.3
—
5
"Assuming digestion of 100 mg of solid
sample with 10 ml of acid.
'"Result for Ni is probably biased by unoptimized
procedure.
Table 5. Percentage of Sample Data Where
Accuracy (Recovery) Exceeds
Arbitrary 100 ± 20% Criterion
Element
Ag
As
Ba
Be
Cd
Cr
Cu
Hg
Ni
Pb
Sb
Se
Tl
Zn
ICP
3i%(i6r
15%( 13)
11%I36)
47%(15)
39%(26)
33%(54>
5%(76)
NA
19%(47)
44%(63)
NA
NA
NA
19%(43>
Technique
XRF
NA}
0%(2)
20%(71)
NA
75%(4)
35%(79)
41%(39)
NA
21%(90)
29%(34)
NA
0%(1)
NA
2%(49)
INAA
NA
0%(2)
0%(J6)
NA
50%(4)
44%(1S)
100%(1)
2O%(5)
62%(13)
25%(4I
86%(7)
0%(1 1
NA
12%(17>
"Numbers in parentheses indicate the quantity
of data records for a technique.
\"NA" indicates information Not Available.
gives better results for Zn. The case of Pb
is somewhat misleading for it appears
that INAA gives comparable results to
XRF. This observation would be disturbing
since INAA is known to be a poor trace
Tables. Comparison of ICP. INAA and XRF Characteristics
Characteristic
Relative Ranking
(Best to Worst)
1 Rapid Analysis
2 Detection Limits
3 Precision and Accuracy
4 Ease of Error Corrections
5 Low Cost
6 Flexibility
7 Availability
8 Ease of Sample Preparation
XRF>ICP>INAA
ICP, INAA>XRF
INAAXCP, XRF
INAA. ICP>XRF
ICP>XRF»INAA
ICP, INAA>XRF
ICP>XRF>INAA
INAA>XRF>ICP
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Table 6. Percentage of Sample Data Where
the Relative Standard Deviation
Exceeds Arbitrary 20% Criterion
Technique
Element
Ag
As
Ba
Be
Cd
Cr
Cu
Hg
Ni
Pb
Sb
Se
Tl
Zn
ICP
20%(5r
14%(7)
0%(12)
0%(7)
4%(27)
0%{28)
12%(49)
NA
16%(43)
3%(30)
0%(2J
NA
NA
2%(40)
XRF
NA]
40%(5)
8(12)
NA
100%(1)
21%(34)
29%(17)
NA
18%(38)
18%(1 1)
NA
0%(1)
NA
0%(20)
INAA
NA
45%(1 1)
6%(35)
NA
NA
19%(26)
0%(1i
NA
53%(15)
NA
46%(13)
0%(2J
NA
8%I12)
^Numbers in parentheses indicate the quantity
of data records for a technique.
\"NA" indicates information Not Available.
technique for Pb. Closer inspection
revealed that the INAA Pb results are
based on only four samples with extremely
high levels of Pb.
The relative importance of the various
sources of analytical error for the three
techniques is shown in Table 7. For both
INAA and XRF, the counting errors are
the least significant error and never
amount to more than 1%. For XRF,
sample preparation is the most important
source of error because it is directly
related to the./ionspectral errors which
are a major problem in XRF. Unless
sample preparation is adequate, satisfac-
tory data will never be generated no
matter how elaborate the nonspectral
correction procedures. Nonspectral errors
rank second in importance followed by
spectral interference errors and then
instrumental errors. The different types
of spectral interferences are well docu-
mented and can usually be anticipated
and corrected. Adequate correction for
spectral and nonspectral errors is com-
pletely dependent on the operator's skill
and experience. Instrumental error
results in a small residual background.
This error can be corrected by plotting the
spectral background as a function of the
Compton scattered radiation and discern-
ing the value of the y-intercept. For INAA,
both instrument and sample preparation
errors are minimal. The major source of
INAA error is spectral interference, and
the major requirement for adequate
correction is an experienced operator
skilled in making confirmative isotope
measurements for an element. The major
source of error for ICP is sample prepara-
tion because of the potential for contam-
ination or loss of analyte during this
step. Spectral interference is the next
most important source of error in ICP
because correction is dependent on the
skill and experience of the operator in
recognizing these errors. Instrumental
drift is usually not a serious ICP problem,
if re-calibration is performed periodically.
XRF is far superior to ICP and INAA in
its ability to generate a rapid semi-
quantitative analysis scan of a sample in
less than 5 minutes. The sample prepara-
tion time for ICP takes well over an hour
while INAA requires weeks to allow
sample activity decay for certain elements.
XRF could, therefore, have utility as a
preliminary screening technique for
hazardous waste samples of totally
unknown composition.
ICP is the least costly of the three
methods in terms of both capital invest-
ment and operating costs. In addition,
commercial services for ICP are low in
cost compared to XRF or INAA. The cost of
operating an XRF system is comparable
to ICP although more extensive computer
facilities are required. The expense of
operating an INAA system is on the order
of 5 to 10 times that of ICP or XRF, and
even commercial service fees are 5 to 10
times higher.
Conclusions
After considering detection limits,
precision, accuracy, errors and correction
procedures, expense, flexibility, availabil-
ity and sample preparation, ICP appears
to be the multielemental technique most
amenable to analysis of hazardous
waste samples; XRF may be most useful
as a preliminary of hazardous waste
samples; and XRF may be most useful as
a preliminary screening technique. Any
literature review suffers from:
a. A lack of comparable databases for
individual techniques with respect to
sample types, definition of detection
limits, and elements.
b. An inherent bias that published data
are typically the best available and
not indicative of what may be
observed in routine applications.
A laboratory comparison of identical
samples by all three techniques is
necessary before a more comprehensive
comparison can be made for determining
these elements in wastes that are
potentially hazardous.
Table 7. Ranking the Importance of Error Sources for ICP. INAA and XRF
Error Categories
Technique
ICP
INAA
XRF
Sample
Prep
1
3
1
Instrumental
3
4
4-5
Counting
5
5
Non-
Spectral
4
2
2
Spectral
2
1
3
1 = High (very important).
5 = Low (Trivial).
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The EPA author Thomas A. Hinners (also the EPA Project Officer, see below) is
with the Environmental Monitoring Systems Laboratory, Las Vegas, NV89114;
J. A. Oppenheimer. A. D. Eaton, and L Y. C. Leong are with James M.
Montgomery. Consulting Engineers, Pasadena. C A 91101.
The complete report, entitled "Multielemental Analytical Techniques for
Hazardous Waste Analysis: The State-of-the-Art." (Order No. PB 84-178 425;
Cost: $13.00, subject to change) will be available only from:
National Technical Information Service
5285 Port Royal Road
Springfield, VA22161
Telephone: 703-487-4650
The EPA Project Officer can be contacted at:
Environmental Monitoring Systems Laboratory
U.S. Environmental Protection Agency
P.O. Box 15027
Las Vegas, NV89114
United States
Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
Official Business
Penalty for Private Use $300
U.S. GOVERNMENT PRINTING OFFICE: 1984-759-102/0977
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