United States
Environmental Protection
Agency
Environmental Monitoring and
Support Laboratory
Cincinnati OH 45268
Research and Development
EPA/600/S4-85/071 Dec. 1985
4>ER/\ Project Summary
-/
USEPA Extraction Method
Development Study for
Trace Metals in Leachate
J. Maney and T. Copeland
US. Ef.vwonmentil Protection Agency
Region V, U&rtry
230 South DearMffn Street
Chicago, Illinois 6060* , ..,x
A study was performed to determine
the applicability of currently approved
analytical methods for conducting the
extraction procedure (EP) toxicity test
required by the Hazardous Waste and
Consolidated Permit Program. The first
phase of the study was designed to
determine the necessity for performing
digestion of the EP leachates prior to
trace element analysis and also to
determine the effect, if any, of preser-
vation on total metal concentrations.
Four matrices were used for this phase
of the study (river sediment, fly ash,
low-pH sludge, and oil/water waste)
and analyses were performed for 17
elements by both atomic absorption
spectrophotometry (AAS) and by In-
ductively Coupled Argon Plasma Emis-
sion Spectrometry (ICP). Digestion of
the leachates generally reduced inter-
ferences and improved the accuracy of
the analyses. For one high sulfur waste,
however, digestion introduced a chem-
ical interference. Acid preservation of
the wastes did not significantly affect
the results.
The second phase of the study was
designed to determine the effect of pH
and time on metal concentrations in the
leachate from low-pH sludge. Deter-
minations were made for 17 elements
in the EP extracts after adjustment of
initial pH to levels of 2, 4, 6 and 8.
Extractions were performed 0, 2,8 and
16 hours following pH adjustment. All
wastes exhibited a strong dependence
on the initial pH of the wastes—the
leachate concentrations were lowered
at higher initial pH values. The time
between pH adjustment and initiation
of the extraction procedure did not alter
the results.
The third phase of the study was
designed to determine the efficiency of
the EP toxicity procedure in extracting
metal spikes from three standardized
reference materials (river sediment, fly
ash, and EPA Municipal Digested
Sludge). The results of this phase con-
firmed the strong pH dependence of
leachate concentrations found in Phase
2 and demonstrated that under normal
EP extraction conditions extraction
efficiencies for most metals are low.
A study was also performed to de-
termine if metal concentrations were
affected by various matrices encounter-
ed using the EP procedures (acetic acid
[0.6%], nitric acid [0.5%], or acetic acid
[0.6%]/nitric acid [0.5%]). Of all the 17
elements studied, only selenium exhib-
ited a matrix effect from the dilute
acids. The slopes of the selenium cali-
bration curves generated by both ICP
and AAS were enhanced in the presence
of acetic acid.
This Project Summary was developed
by EPA's Environmental Monitoring and
Support Laboratory, Cincinnati, OH. 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
This investigation was conducted in
three separate phases with each phase
focusing on specific questions related to
the applicability of various aspects of
approved methods for conducting the EP
toxicity tests and subsequent analyses.
Phase 1 of the study was designed to
determine the necessity of performing
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leachate digestion after the EP toxicity
test a nd to determ i ne the effect of preser-
vation on metal concentrations. Four
materials were tested—river sediment,
fly ash, a low-pH sludge, and oil/water
waste. For the oil/water waste, a separate
extraction and analysis was performed on
the oil phase. For all extractions, analyses
were performed in triplicate using atomic
absorption spectrophotometry (AAS) and
inductively coupled argon plasma emis-
sion spectroscopy (ICP).
The second phase was designed to
determine the effect of pH and time on
leachate metal concentrations from the
low-pH sludge. The waste was extracted
at 0, 2, 8 and 16 hours after pH adjust-
ment, with the pH adjustments being
made at levels of 2,4,6 and 8 with 1.0 M
sodium hydroxide. Analyses were per-
formed in triplicate using both AAS and
ICP.
The third phase of the study was
designed to determine recovery of metal
spikes from three standardized reference
materials. The three standardized refer-
ence materials (river sediment, fly ash,
and EPA Municipal Digested Sludge) were
spiked in triplicate at three levels, ex-
tracted according to the EP toxicity test
procedures, and analyzed using AAS and
ICP.
Preliminary to all three phases, a
calibration study was performed to de-
termine the effect, if any, of the acid
matrix (0.6% acetic, 0.5% nitric or 0.6%
acetic andO.5% nitric) on the slopes of the
calibration curves.
Procedure
Calibration Study
Standards for the calibration study
were prepared by dilution of 1000 ppm
Fisher or Ventron certified reference
standards with the appropriate matrix.
Ultrex acetic and nitric acids were used
for preparation of the standard matrices
(0.6% acetic acid, 0.5% nitric acid, and
0.6% acetic acid/0.5% nitric acid). Mixed
standards were used for all elements
except As, Hg, Se and Ag which were
prepared individually and were prepared
daily to minimize losses.
Phase 1 Analyses
Phase 1 analyses were performed on
samples of river sediment, fly ash, low-pH
sludge, and oil/water waste. The Phase 1
procedures consisted of the following
general analytical schemes:
Scheme 1—EP test with leachate diges-
tion
Scheme 2—EP test without leachate
digestion
Scheme 3—Digestion according to EPA
procedures with sample
stored at room temperature
Scheme 4—Digestion according to EPA
procedures with sample pre-
served by addition of nitric
acid (HN03) to pH <2
Analytical results from Schemes 1 and 2
were used to evaluate the requirement to
digest leachates resulting from the EP
test. Results for Schemes 3 and 4 were
used to evaluate sample storage require-
ments.
Modified procedures were utilized for
the following elements: As and Se—EPA
Methods 206.2 and 270.2, Hg—Method
245.1; and Sb—Method 204.2. Analyses
were performed by AAS according to
methods specified by EPA and Perkin-
Elmer. Graphite furnace AAS was used
for atomic absorption determination of As
and Se and cold-vapor AAS was used for
determination of Hg. All other elements
were determined by flame methods.
Analyses were also performed by ICP
according to methods specified by EPA
and Jarrell-Ash. Extractions and analyses
were performed in triplicate.
The sequence of events occurring for
each Scheme of Phase 1 of the project are
summarized below:
Scheme 1—Divide sample aliquot into
triplicates, perform EP extrac-
tion, digest the extract (sepa-
rate digestions for Ag, Hg
and Sb), analyze, spike, wait
two weeks, analyze by AA.
Scheme 2—Divide sample aliquot into
triplicates, perform EP extrac-
tion, analyze, spike, wait two
weeks, analyze by AA.
Scheme 3—Divide sample aliquot into
triplicates, digest the tripli-
cates (separate digestions for
Ag, Hg and Sb), analyze,
spike, wait two weeks, ana-
lyze by AA.
Scheme 4—Exactly as in Scheme 3 only
use the acid preserved
sample aliquot.
Phase 2 Analyses
For the Phase 2 analyses of the low-pH
sludge, 16 separate aliquots were re-
moved, subsampled in triplicate, and
adjusted to pH levels of 2, 4, 6 and 8 by
addition of 1 M sodium hydroxide(NaOH).
At times of 0,2, Sand 16 hours following
pH adjustment, one triplicate subsample
from each pH level was extracted using
the EP toxicity test procedure and ana-
lyzed for 17 trace metals. Details of
extraction and analysis were identical to
those described in the section entitled
"Phase 1 Analyses," for Scheme 2.
Phase 3 Analyses
These standardized reference materials
were prepared by drying, grinding, and
homogenizationof river sediment, fly ash,
and EPA Municipal Digested Sludge (the
latter material required only homogeniza-
tion). After the determination of total
metal concentrations, each sample was
divided into 10 aliquots and prepared for
extraction according to procedures speci-
fied for the EP toxicity test. After addition
of distilled water, each material was
spiked in triplicate at levels approximating
50, 100 and 150% of the total metal
concentration using Fisher certified ref-
erence standards. An unspiked sample
was subjected to the EP test as a control
and to allow correction for the background
metal concentration in the leachate.
During addition of the standard spiking
solutions, pH was either allowed to
change or was maintained at its initial
level by concurrent titration with 0.25 N
sodium carbonate (Na2C03). After spike
addition, samples were extracted and
analyzed using methods identical to those
presented in Phase 1, Scheme 2.
Results and Discussion
Calibration Study
For each of 17 elements, the slope,
intercept, and correlation coefficient for
the calibration curve are presented.
Actual calibration curves are also pre-
sented.
For all elements except Se, the slopes
of the calibration curves for standards
prepared in 0.6% acetic acid and 0.6%
acetic acid/0.5% nitric acid were within
±5% of the slopes of the reference
standards prepared in 0.5% nitric acid. In
the case of Se, the slope of the calibration
curve in the 0.6% acetic acid was 14%
greater than the slope of the calibration
curve in 0.5% nitric acid.
River Sediment
For nine elements (Al, Ba, Be, Cd, Fe,
Pb, Mn, Ni and Zn) no statistically signif-
icant differences were observed between
digested and undigested leachates.
Recoveries of spikes from the analyte
solutions determined by AAS are pre-
sented. Recoveries were within the range
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of 80-120% except for As, Hg, Ag and Zn,
which had recoveries of 109-141%, 66-
99%, 73-108% and 47-85%, respectively.
No significant differences were found
between the digested and undigested EP
leachates for any elements present above
the detection limits for the river sediment
sample. Significant differences between
Schemes 3 and 4 (unpreserved and
preserved sample aliquots, respectively)
were found by AAS for As, Fe and Ag.
However, none of these differences were
statistically significant when analyzed by
ICP. For all three elements, concentra-
tions as determined by AAS were higher
in the unpreserved sample.
Recoveries of spikes for all four
schemes analyzed by AAS were between
80-120% except for As, Hg, Ag and Zn.
Zinc recoveries were consistently low
(47-85%), As recoveries consistently high
(109-141%). Silver and Hg recoveries
were low only for the nitric acid preserved
(Scheme 4) samples. The Zn and As
recoveries from the fly ash samples also
followed these trends indicating a positive
interference for As and a loss of Zn to the
residual solids or to the glassware.
Recoveries of spikes of 11 elements (Al,
Sb, Be, Cd, Cu, Fe, Mn, Hg, Ni, Ag andTI)
were in the range of 80-120%. Recoveries
for the remaining six elements were as
follows: As, 116-143%; Ba, 0-108%; Cr,
108-128%; Pb, 70-101%; Se, 30-95%;
and Zn, 70-88%.
Significant differences for fly ash EP
leachates were found for Cu, N i and Se by
AAS and for Ba, Cd and Cr by ICP.
Differences for Cu and Ni were not
significant by ICP and Se was below the
ICP detection limit. Cu and Ni by AA are
affected by Fe and other transition metals.
The difference in Ba concentrations be-
tween the digested and undigested leach-
ates is over an order of magnitude (the
undigested value higher).
As with the river sediment samples, Zn
recoveries were consistently low. As
recoveries consistently high. In addition,
Cr recoveries were somewhat high par-
ticularly for the completely digested
(Scheme 3) sample supporting the possi-
bility of contamination during digestion.
Recoveries of Ba, Pb, Se and Ag were
low for the digested EP leachate (Scheme
1). The fly ash sample was generated
from fuel containing significant levels of
sulfur and the possibility of sulfate forma-
tion during digestion with subsequent
precipitation of insoluble sulfatesfBa, Pb,
Ag) is highly likely. The low Se recovery
cannot be explained by sulfate precipita-
tion but may be due to the formation of
nickel sulfides rather than nickel sele-
nides in the graphite furnace with sub-
sequent loss of SeC>2
Low pH Sludge
For the Scheme 1 and 2 data, concen-
trations of seven elements (Sb, Ba, Be,
Hg, Se, Ag and Tl) were below the limit of
detection of the analytical methods and
no statistical comparisons could be per-
formed. For six elements (Al, Cr, Cu, Fe,
Pb and Mn), no significant differences
were detected. For four elements (As, Cd,
Ni and Zn), significant differences were
detected using AAS results. For Cd, Ni
and Zn, differences were not significant
using ICP data. For the Scheme 3 and 4
data, which compared preserved and
unpreserved sample aliquots, five ele-
ments (Sb, Be, Se, Ag and Tl) were below
the limits of detection. By AAS, no
significant differences were detected for
Al, As, Ba, Cd, Cu, Pb, Mn and Zn.
Significant differences were detected for
Cd, Fe, Mn and Ni by AAS and for Cu, Fe,
Pb, Mn and Ni by ICP.
Recoveries of spikes for 11 elements
(Al, Sb, Be, Cd, Cr, Cu, Fe, Mn, Hg, Ni and
Tl), were in the range of 80-120%.
Recoveries for the remaining elements
were as follows: As, 56-92%; Ba, 0%; Pb,
41 -89%; Se, 78-98%; Ag, 7-24%; and Zn,
86-128%.
The AAS data for Schemes 1 and 2
indicate significant differences for As, Cd,
Ni and Zn. Arsenic levels were below ICP
detection limits while the ICP data for Cd,
Ni and Zn showed no differences. The As
values for the undigested leachate are
higher than for the digested sample. Two
possible causes are that As is lost during
digestion or that there is a spectral
interference in the undigested sample.
Spike recoveries for the undigested
sample averaged 56% and for the digested
sample 84%, supporting the likelihood of
an interference in the undigested sample.
The practical significance of the AAS
Cd data is suspect. The high precision
allows 0.23 and 0.24 mg/L to be statis-
tically different.
The nickel data for the digested leachate
are higher (by both AAS and ICP although
not significant by ICP). Since the differ-
ence is small, contamination during
digestion or slight nonhomogeneities in
the sample aliquots are the likely causes.
An enhancement of flame AAS analyses
for Ni by large excesses of Fe is well
known.
In the comparison of Schemes 3 and 4,
the AAS data are significantly different
for Cd but the ICP data are not. For Cu, the
ICP data are significantly different while
the AAS data are not. An examination of
the raw data again suggests that these
results are the mathematical conse-
quence of high precision rather than of a
practical difference. The Pb data for ICP
Scheme 3 (unpreserved) are higher than
for the preserved sample while the AAS
data show no difference. Both the Scheme
3 and Scheme 4 ICP values are higher
than the AA results. The most likely
explanation of this is that it is a conse-
quence of a spectral interference from
the extremely high levels of Fe, Mn or Ni
present in this sample. If the difference
were due to a true chemical change in the
unpreserved sample or a sample non-
homogeneity, the AAS results should
also reflect the increased concentration.
Recoveries of spikes from this waste
were generally high with two exceptions:
As and Se recoveries from the undigested
EP leachate were low and elements
forming insoluble sulfates had universally
poor recoveries (Ba, Pb and Ag).
Oil/ Water Waste
For data from Schemes 1 and 2, only
two elements (Fe and Mn) were present
at concentrations above the limit of
detection and no significant differences
were evident. For data from Schemes 3
and 4, all elements except Sb, As, Se, Ag
and Tl were present at concentrations
above the limit of detection and no signif-
icant differences were detected.
Oil phase analyses indicated measur-
able amounts of Al, Ba, Cu, Fe, Pb, Mn
and Ni in the leachates. For purposes of
comparison, concentrations were calcu-
lated on the same basis as the previous
phase leachate. The fractions of the total
metal contained in the oil phase were as
follows: Al, 32-57%; Ba, 9-12%; Fe, 26-
29%; Mn, 17-24%; and Ni, 44%.
For 15 elements (Sb, As, Ba, Be, Cd, Cr,
Cu, Fe, Pb, Mn, Ni, Se, Ag, Tl and Zn),
recoveries were in the range of 80-120%.
Recoveries of the remaining elements
were as follows: Al, 96-124%; and Hg,
15-104%.
Phase 2 Analyses
Aliquots of the sludge were adjusted to
pH 2, 4, 6 and 8 with 1 M NaOH and then
extracted at time intervals (post-pH ad-
justment) of 0, 2, 8 and 16 hours. Of the
17 elements in this study, 10 were
present in the pH 2 samples at concentra-
tions above the analytical detection limits
(Al, As, Cd, Cr, Cu, Fe, Pb, Mn, Ni andZn).
None of the metals exhibited a strong
leachate concentration dependence on
the time interval between pH adjustment
and extraction. However, 9 of the 10
elements present (As being the single
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exception) exhibited strong concentration
dependence on pH during the EP leachate
generation. It should be noted that the
aliquots of sludge which were adjusted to
pH 6 or 8 were (at the appropriate time
interval) adjusted to pH 5 as would be
required by the EP test. The extracts were
analyzed without digestion, that is, by
procedures analogous to Phase 1,
Scheme 2.
Phase 3 Analyses
The purpose of Phase 3 was to deter-
mine the efficiency of the EP in extracting
metal spikes from standard reference
materials. The materials chosen were fly
ash, river sediment, and EPA Municipal
Digested Sludge. The fly ash and river
sediment were dried, ground, and ho-
mogenized prior to use. The samples of
dried municipal sludge were composited
to obtain a sufficient quantity of homog-
enous material for the study.
Aliquots of all three materials were
digested and analyzed in triplicate by AAS
to provide the total bulk concentrations of
the 17 metals in the reference materials.
The results obtained by ERGO were
confirmed by an outside laboratory.
Each sample was prepared for the EP
extraction according to the EPA specified
methods. After addition of distilled water
to the dried ash, sediment and sludge, the
samples were spiked (in triplicate) at
three different concentration levels rep-
resenting 150%, 100%, and 50% of the
total metal content or 20,10, and 5 times
the detection limit for those elements
which were not detected in the bulk
analyses of the materials. Due to the acid
content of the spiking solutions, the pH of
the spiked sample/distilled water mat-
rices ranged from 1.39 to 3.28. This pH
range is low for EP extractions where the
pH of neutral or basic sludges are typically
adjusted to pH 5.0 ± 0.2 with acetic acid.
For a second series, the sample pH was
maintained at its initial level during spike
addition by concurrent titration with 0.25
H. NaaCOa. These samples were then
adjusted to pH 5 and extracted according
to the EP test procedure.
Blank spike recoveries at the 150%,
100%, and 50% levels for the pH 5
samples and at the 100% spike level for
the low-pH samples are also included.
. Recoveries for most metals in the blank
spikes were in the range 85% to 115%
with the certain exceptions.
For the pH 5 adjusted river sediment
samples, recoveries ranged from <1 % to
169%; for the low-pH samples, the re-
coveries ranged from 1% to 323%. In
general, recoveries of the high (150%)
spikes were higher thanfor the low(50%)
spikes. The most obvious difference is
that the recoveries for the low-pH samples
are much higher and much closer to
100% than the pH 5 recoveries.
The recoveries of Se, Sb and As were
poor for both low-pH and pH 5 extracts.
These elements would most likely be
present as oxyanions and would not
precipitate as hydroxides. The most likely
mechanisms of loss of those would be
adsorption or co-precipitation.
Fly Ash
The fly ash samples were dried, ground,
and homogenized prior to bulk analysis
and Phase 3 extractions. Bulk concentra-
tions of the elements of interest were
determined by ERCO and verified by an
outside laboratory.
Mean recoveries of 17 elements were
calculated by averaging results for both
AAS and ICP and correcting (where
possible) for the concentration of each
element determined from an unspiked EP
for each material. The concentration of
element recovered was then compared to
the original concentration added to de-
termine the percent recovery.
As with the river sediment samples,
recoveries from the low-pH extracts were
consistently better than from the pH 5
extracts and the recoveries of the anionic
species (As, Sb, Se) were low at both pH
values; Ni, again exhibited high recoveries
(particularly by AAS) due to Fe interfer-
ence. In addition, the fly ash samples
exhibited low recoveries for those ele-
ments with insoluble sulfates (Ba, Pb) as
didthe fly ash samples utilized in Phase 1.
EPA Municipal Digested Sludge
Each sample was prepared for the EP
extraction according to methods outlined
by EPA and in the manner that was
employed for the fly ash and river sedi-
ment samples. Mean recoveries were
calculated by averaging results for both
AAS and ICP and correcting (where
possible) for the concentration of each
element determined from the appropriate
unspiked EP for each material. The con-
centration of element recovered was then
compared to the original concentration
added to determine the percent recovery.
Recoveries of the metals in the blank
spikes were all between 90% and 110%
with the exception of Ag which is unstable
in the mixed standards and Hg which was
spiked at low levels.
Recoveries of the metals in the extracts
were extremely poor. For the pH 5 ex-
tracts, no element exhibited recoveries in
the 80% to 120% range. For the low-pH
extracts only four of the 51 recoveries
were in the 80% to 120% range. Re-
coveries in the pH 5 extracts were all
extremely low (except Hg) while the low-
pH recoveries were highly erratic. For the
low-pH extracts, Sb, Pb, Ba, Se and Ag
exhibited low recoveries. The Ag was
expected to be low since the spike solution
contains chloride and precipitates the Ag.
The digested sludge apparently contains
sulfate which would selectively precipi-
tate Pb and Ba. The Sb and Se recoveries,
as with the fly ash and river sediment,
were low for both the low-pH and pH 5
extracts.
Comparison of AAS and
ICP Recoveries
While the intent of Phase 3 was to
determine the ability of the EP test to
leach spikes from standard reference
materials, the data are also useful in
observing the comparative performance
of AA and ICP. Both techniques were
used to analyze the same undigested EP
leachates with the same spike levels and
consequently comparison of their per-
formance was straightforward.
Conclusions and
Recommendations
The EP toxicity test was designed to
indicate the concentrations of eight
metals (As, Ag, Ba, Cd, Cr, Hg, Pb and Se)
present in a waste in forms which would
allowthem to become mobile(solubilized)
in a mildly acidic (pH 5 acetic acid)
medium. Analyses of the generated
leachates are performed by atomic absorp-
tion spectrophotometry (AAS).
The conclusions which may be drawn
from this study and recommendations
based upon the conclusions are sum-
marized below.
Calibration Study
• For 16 of the 17 metals studied, the
dilute nitric acid or dilute acetic acid
matrices used for the EP toxicity test
had no effect on the slopes of the
calibration curves. The acetic acid
matrix enhanced the Se signal by both
AAS and ICP. Since enhancements of
almost 10% were found for both AAS
and ICP, it is recommended that the
method of standard additions be used
for Se analyses or at least that a test be
performed to ensure that standard
additions are not needed for every EP
leachate.
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Phase 1 (AcidPreservation and
Digestion Study)
• Digestion of the EP leachates removes
several interferences and is generally
recommended prior to analysis by
either AAS or ICP. However, digestion
may cause losses from certain samples
such as the high sulfur containing fly
ash studied here. Digestion caused
formation of sulfate and subsequent
precipitation of Ba, Ag and Pb.
• Acid preservation of the samples used
in this study caused little difference in
analytical results.
• The ICP analyses of undigested leach-
ates were less subject to interference
than were AAS analyses.
• Even though the leachate digestion of
the fly ash resulted in losses of Ba, Ag
and Pb for this sample, it is recom-
mended that the digestion be per-
formed. Several matrix interferences
in all the wastes were eliminated by
the digestion procedure which other-
wise would have required time-con-
suming techniques such as standard
additions.
Phase 3 (Extraction
Efficiency Study)
• The pH 5 dilute acetic acid matrix used
for the leachate generation in the EP
toxicity test is not capable of leaching
many metals from a solid waste and is
incapable of preventing precipitation
or adsorption of metal ions spiked into
the solution. In fact, a river sediment
containing 5,700 yug/g Al and 9,200
jug/g Fe was leached with an acetic
acid pH 5 solution containing 42.5
mg/L Al (and 68.5 mg/L Fe) with
recoveries of the metals in solution
being less than 3%.
• As in Phase 1, the ICP analysis of
undigested leachates was less subject
to interference (as measured by %
recoveries) than was AAS.
Phase 2 fpH and Storage
Time Study)
• The time that a sample is stored (0 to
16 hours) prior to the initiation of the
EP leachate generation had no effect
on the metal concentrations in the
leachate.
• The pH of the sample prior to the
initiation of the EP leachate generation
is extremely important. This may be
true only for selected wastes such as
the ones used in this study, i.e., one
with a high Fe content which may
precipitate at pH 5 or one with a high
sulfate concentration which may also
cause precipitation. It would be useful
to perform Phase 2 on wastes where
hydroxide or sulfate precipitation were
less likely.
The fact that the leachate concentra-
tions are pH dependent was further
confirmed by the Phase 3 data. Due to this
variability in recovery (extraction effi-
ciency) it is recommended that the intent
of the EP toxicity test be emphasized, i.e.,
that it is an indicator of the concentration
of mobile metal species not a total
extraction procedure.
U. S. GOVERNMENT PRINTING OFFICE:1986/646-l 16/20729
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J. Maneyand T. Copelandare withERCO/A Division ofENSECO, Cambridge. MA
02140.
John D. Pfaff is the EPA Project Officer (see below).
The complete report, entitled "US EPA Extraction Method Development Study for
Trace Metals in Leachate." (Order No. PB 86-118 981/AS; Cost: $16.95.
subject to change) will be available only from:
National Technical Information Service
5285 Port Royal Road
Springfield, VA 22161
Telephone: 703-487-4650
The EPA Project Officer can be contacted at:
Environmental Monitoring and Support Laboratory
U.S. Environmental Protection Agency
Cincinnati, OH 45268
United States
Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
Official Business
Penalty for Private Use $300
EPA/600/S4-85/071
0000329 PS
AGENCr
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