United States
Environmental Protection
Agency
Municipal Environmental Research EPA-600/2-79-1 54
Laboratory August 1979
Cincinnati OH 45268
Research and Development
Elutriate Test
Evaluation of
Chemically
Stabilized Waste
Materials
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F3 -
'
Research reports of the Office of Research and Development, U S. Environmental
Protection Agency, have been grouped into nine series. These nine broad cate-
gories were established to facilitate further development and application of en-
vironmental technology Elimination of traditional grouping was consciously
planned to foster technology transfer and a maximum interface in related fields.
The nine series are-
1 Environmental Health Effects Research
2. Environmental Protection Technology
3 Ecological Research
4 Environmental Monitoring
5 Socioeconomic Environmental Studies
6 Scientific and Technical Assessment Reports (STAR)
7 Interagency Energy-Environment Research and Development
8. "Special" Reports
9. Miscellaneous Reports
This report has been assigned to the ENVIRONMENTAL PROTECTION TECH-
NOLOGY series. This series describes research performed to develop and dem-
onstrate instrumentation, equipment, and methodology to repair or prevent en-
vironmental degradation from point and non-point sources of pollution. This work
provides the new or improved technology required for the control and treatment
of pollution -sources to meet environmental quality standards.
This document is available to the public through the National Technical Informa-
tion Service, Springfield, Virginia 22161.
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EPA-600/2-79-151*
August 1979
ELUTRIATE TEST EVALUATION OF CHEMICALLY
STABILIZED WASTE MATERIALS
Douglas W. Thompson
Environmental Engineering Division
Environmental Laboratory
U.S. Army Engineer Waterways
Experiment Station
Vicksburg, Mississippi 39180
Interagency Agreement No. EPA-IAG-D^-0569
Project Officer
Robert E. Landreth
Solid and Hazardous Waste Research Division
Municipal Environmental Research Laboratory
Cincinnati, Ohio ^5268
MUNICIPAL ENVIRONMENTAL RESEARCH LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
CINCINNATI, OHIO 1*5268
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DISCLAIMER
This report has been reviewed by the Municipal Environmental Research
Laboratory, U. S. Environmental Protection Agency, and approved for publica-
tion. Approval does not signify that the contents necessarily reflect the
views and policies of the U. S. Environmental Protection Agency, nor does
mention of trade names or commercial products constitute endorsement or
recommendation for use.
ii
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FOREWORD
The Environmental Protection Agency vas created because of increasing
public and government concern about the dangers of pollution to the health
and welfare of the American people. Noxious air, foul water, and spoiled
land are tragic testimony to the deterioration of our natural environment.
The complexity of that environment and the interplay between its components
require a concentrated and integrated attack on the problem.
Research and development is that necessary first step in problem solu-
tion and it involves defining the problem, reasuring its impact, and search-
ing for solutions. The Municipal Environmental Research Laboratory develops
new and improved technology and systems for the prevention, treatment, and
management of wastewater and solid and hazardous waste pollutant discharges
from municipal and community sources, for the preservation and treatment of
public drinking water supplies, and to minimize the adverse economic, social,
health, and aesthetic effects of pollution. This publication is one of the
products of that research; a most vital communications link between the
researcher and the user community.
This report presents results from the evaluation of the use of a distill-
ed water elutriate or shake test for comparing the effectiveness of a variety
of solidification/stabilization (fixation) systems on containing undesirable
materials in semisolid wastes (sludges). It provides basic data that will
add to our knowledge regarding land disposal of treated wastes and will assist
in the development of adequate waste testing techniques.
Francis T. Mayo, Director
Municipal Environmental Research
Laboratory
111
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ABSTRACT
A distilled water shake test, the elutriate test, was developed and test-
ed to provide a fast, simple, procedure for predicting the escape of pollu-
tants from treated and untreated sludges. The preliminary test consisted of
subjecting various treated and untreated flue gas desulfurization (FGD) and
industrial waste sludges to the elutriate test procedure and measuring the
levels of a wide variety of constituents in the elutriate and comparing these
with analyses of digested sludges. The resulting data are presented as per-
cent attenuation and a comparison is made between treated and untreated
wastes.
The short-term elutriate test results were compared to results of a long-
term leaching test using the same treated and untreated sludges. The results
suggest that the elutriate test may be useful in predicting the pollutant
potential of various treated or untreated wastes. Further research and modi-
fications are suggested to improve the predictive value of the test.
This report is submitted in partial fulfillment of Interagency Agreement
No. EPA-IAG-D4-0569 between the U.S. Environmental Protection Agency, Munici-
pal Environmental Research Laboratory, Solid and Hazardous Waste Research
Division (EPA, MERL, SHWRD) and the U.S. Army Engineer Waterways Experiment
Station (WES). Work for this report was conducted during the period of
August 1976 through August 1977.
iv
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CONTENTS
Foreword iii
Abstract iv
Figures vi
Tables vii
Acknowledgment viii
1. Introduction 1
2. Conclusions h
3. Recommendations 5
U. Materials and Methods 6
5. Elutriate Test 11
6. Presentation of Elutriate Test Results 15
T. Interpretation of Elutriate Test Results U5
8. Elutriate Test and Long-Term Leaching Test Comparison hQ
References 6l
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FIGURES
Number Page
1 Total weight of metal species leached with respect
to time ^9
2 Sample 500A - Ca linear plot 50
3 Sample 500A - Ca exponential plot 51
U Sample 500R - Pb 52
5 Sample 500A - Ni 53
6 Sample 500R - Mn 5^
7 Sample 500G - Mg 55
8 Sample 500G - Cu 56
9 Sample 500G - Ca 57
VI
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TABLES
Number Page
1 Identification of Sludges 7
2 Identification of Fixation Processes 8
3 Chemical Analysis 10
U Analysis of Elutriate Samples (General) 16
5 Analysis of Elutriate Samples (Metals) 20
6 Analysis of Total Digest (Metals) 2k
7 Metal Solubilisation 28
8 Metal Attenuation by Fixation (0 Percent) 39
9 Metal Attenuation by Fixation (50 Percent) hO
10 Metal Attenuation by Fixation (90 Percent) kl
11 Attenuation of Various Metals U2
12 Fly Ash Trace Element Analysis 1|7
VI1
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ACKNOWLEDGMENTS
This investigation was conducted by the Environmental Laboratory of the
U. S. Army Engineer Waterways Experiment Station (WES) Tinder the sponsorship
of the Municipal Environmental Research Laboratory, U. S. Environmental
Protection Agency.
The author wishes to thank Dr- Jerome L. Mahloch for significant techni-
cal advice and assistance in the preparation of this manuscript. The project
was under the general supervision of Dr. John Harrison, Chief, Environmental
Laboratory, Mr. Andrew J. Green, Chief, Environmental Engineering Division,
and Mr. Norman R. Francingues, Chief, Water Supply and Waste Treatment Group.
The guidance and support of Mr. Robert E. Landreth, Mr. Norbert B.
Schomaker, and the Solid and Hazardous Waste Research Division, Municipal
Environmental Research Laboratory, U. S. Environmental Protection Agency are
gratefully acknowledged. The Analytical Laboratory Group performed the chemi-
cal analyses under the direction of Mr. James D. Westhoff, Dr. Donald W.
Rathburn and Mr. Jerry Jones. Mr. Oscar W. Thomas assisted in the sample
preparation. The diligent and patient efforts of Ms. Rosie Lott, Ms. Connie
Johnson, and Ms. Maureen Smart, typists, and Mr. Jack Dildine, graphics
coordinator, are gratefully acknowledged. The Director of WES during the
course of this study was COL J. L. Cannon, CE. Technical Director was Mr.
F. R. Brown.
viii
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SECTION 1
INTRODUCTION
BACKGROUND
Recent concern for the environment has brought about an increase in air
and water pollution control legislation. This legislation calls for the
strict control of pollutant emissions to the environment. The resulting
imposed regulations have brought about an increase in the number and effi-
ciency of pollutant removal systems. The typical treatment system discharges
pollutants in a concentrated form such as a sludge. This sludge must be
disposed so as to result in a negligible impact on the environment. Many
sludges must be considered hazardous to the environment because of high
concentrations of potentially dangerous pollutants and poor handling of
characteristics of the sludges.
The final receptor for sludges is usually the land. In many disposal
systems, a physical barrier such as a clay or man-made liner is placed between
the sludge and the surrounding environment to prevent the migration of poten-
tially hazardous materials from the disposal site. Leaking of pollutants
from the disposal area can occur due to unfavorable reactions between the
liner and the inclosed sludge or as a result of deterioration or accidential
rupture of the liner.
Another method for reducing the migration of pollutants from the sludge
disposal area to the surrounding environment is sludge fixation or solidifi-
cation/stabilization. At present, the two major types of fixation processes
in use are encapsulation and addition of materials that react with the
sludge. Encapsulation methods provide a physical barrier against pollutant
mobility. Fixation processes admix organic or inorganic materials with the
sludges to reduce pollutant mobility generally by altering the chemical
and/or physical properties of the sludge. Chemical alterations are aimed at
reducing the solubility of the pollutants. Physical alterations are aimed at
lowering the permeability of the sludges and decreasing the surface area-to-
volume ratio.
There are certain problems associated with sludge solidification/stabili-
zation. The high cost of total encapsulation processes limit their application
to very toxic sludges usually with relatively small volumes. In most fixation
processes, the admixed materials-to-sludge ratios are difficult to standardize.
Since this fixation technique generally depends on a reaction of additives
with the sludge, it must be tested in advance to determine whether the desired
reaction will take place and the proper conditions for the reaction (additives-
to-sludge ratio pH, moisture content, etc.) exist. After fixation, the
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material must be tested to determine the rate of leaching of pollutants. The
testing procedures generally used involve column leaching and/or an extended
surface wash of the material. These tests are usually performed over a
relatively long time period to allow prediction of future performance of the
fixed sludge for the life of the disposal system.
There is a need for a fast, simple test procedure that can be used to
predict the total pollutant migration from a fixed sludge. A test of this
type will speed up fixation technology development and provide regulatory
agencies with an economical method for evaluating the pollution potential of
any fixed sludge. This report summarizes the development and use of a fast,
simple testing procedure for determining the total pollutant migration from a
raw or fixed sludge.
HISTORY OF ELUTRIATE TEST
The standard elutriate test was developed by the Corps of Engineers in
an attempt to develop a more technically sound approach toward dredged material
disposal. The previous use of bulk chemical composition of the sediment had
not provided a useful index of potential environmental quality problems
associated with disposal (l). This test was designed to be used as a leaching
test using site water. The information obtained from a standard elutriate
test is used as a basis for estimating the potential significance of contami-
nants present in sediment to be dredged.
The standard elutriate test procedure as published in the Federal
Register (2,3) involves the mixing of sediment and disposal site water in a
ratio of 1:U on a volume-to-volume basis. The mixture is shaken for one-half
hour, allowed to settle for one hour, and then filtered or centrifuged prior
to analysis. The analysis of the elutriate water is compared to the analysis
of the site water. A significant increase in the concentration of a parti-
cular contaminant signals a potential problem with the contaminant in the
dredging process.
PURPOSE AND OBJECTIVES
The U. S. Army Engineer Waterways Experiment Station (WES) has under-
taken, through an interagency agreement with the U. S. Environmental Protect-
ion Agency, a study directed toward examining the potential for success of
fixation processes as applied to various sludges to yield products environ-
mentally acceptable for disposal. Several sludges associated with different
industrial processes and with flue gas desulfurization (FGD) systems have
been used in the study. The objectives of the study are as follows:
a) To assess on a laboratory scale the pollution potential, leachability
and physical durability of selected hazardous industrial sludges,
FGD sludges, and fixed sludges from these two categories.
b) To verify the laboratory data by field studies. The study has been
divided into three phases, the first of which is sludge characteriza-
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tion and experimental design. This phase has been completed and is
summarized in an earlier project report (U). The second phase
involves laboratory testing and includes the elutriate test work.
This phase has been partially completed and summarized in an earlier
project report (5). The elutriate test work was not included in
that report. Work is continuing in the second phase of the study
and should soon be completed. Work on the third phase, which involves
field testing, has been recently completed.
The elutriate test was developed to provide a fast, simple test procedure
that can be used to predict the total pollutant migration from a sludge. The
objectives of the elutriate test study were as follows:
a)* To assess the applicability of the elutriate test in predicting
pollutant migration from various hazardous sludges.
b) To assess the correlation between the elutriate test and long-term
leaching tests.
c) To evaluate the performance of various fixation techniques in limit
ing the migration of pollutants from certain hazardous sludges.
This report summarizes the work completed in the elutriate test study.
Work is continuing in the verification of the elutriate test as data becomes
available from other phases of the overall study.
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SECTION 2
CONCLUSIONS
Experimental studies involving the elutriate test have indicated that
such a test can be a very effective aid in evaluating pollutant migration
from various hazardous sludges, but careful interpretation and application of
the results is required.
The elutriate test is not a true analog of a disposal site because no
provisions are made for modeling the attenuation of pollutants by soil or the
dilution of pollutant concentrations by disposal site ground-water, but the
elutriate test does provide a fast, simple technique for comparing raw and/or
fixed sludges on the basis of pollutant migration to the elutriate.
The pollutant concentrations found in the elutriate from the elutriate
test are mainly dependent on the physical durability of the sludge sample
being tested and on the solubility of the pollutants in the sludge sample.
The fixation processes were only partially successful in limiting the
escape of pollutants from the hazardous sludges in this study. Cadmium and
chromium were found to be the most difficult metals to contain. Success
rates for metal containment by fixation were lower for the industrial sludges
than for the FGD sludges.
A review of the fixation processes used in the study identified several
factors that could contribute to the poor success of the fixation processes
in limiting metal migration. These factors include changes in sludge per-
meability, pH control, and the composition of the process additives.
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SECTION 3
RECOMMENDATIONS
Verification of the elutriate test should "be continued as data "become
available from other phases of the overall study.
Although the elutriate test appears to have some potential for evaluat-
ing pollutant migration from sludges, other promising techniques for pre-
dicting pollutant migration should "be investigated, including modifications
of the elutriate test. Two such modifications that should "be investigated
are as follows: l) repetitive testing of the same sludge sample to deter-
mine how migration varies with elutriate volume, and 2) reducing the degree
of agitation to a point where the sludges can maintain their physical integrity
throughout the test.
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SECTION h
MATERIALS AND METHODS
SLUDGES
The sludges used in this study are from both industrial processes and
flue gas desulfurization processes. The selection of the sludges was princi-
pally directed by EPA personnel and was based on availability and composition.
The sludges are identified only by code numbers in this report as has been
done in other reports related to the project (5).
A description of the sludges used in the study along with the identif-
ying numerical code for each sludge is presented in Table 1. Chemical and
physical properties of the sludges have been presented in an earlier project
report (5).
FIXATION
The fixation processes used in this study have been discussed in detail
in an earlier project report (5). A brief description of each fixation
process, along with its identifying alphabetical code, is presented in Table
2. Elutriate test evaluations were not made on fixed sludge specimens pre-
pared using process D (total encapsulation). This process involves encapsulating
the sludge in a 0.6** centimeter plastic jacket. Previous testing had indicated
very little potential for pollutant migration from sludges fixed with this
process.
ELUTRIATE TEST PROCEDURE
The elutriate test conducted on the sludges is based on a standard
elutriate test (l). The methodology for the elutriate test used on the raw
sludges is as follows:
a) Place 200 mH of sludge in a 1000-mJ!, graduated Erlenmeyer flask and
fill to 1000 m£ with deionized water.
b) Shake vigorously for 30 minutes.
c) Centrifuge at 2500 rpm for 20 minutes.
d) Filter centrifugate through a 0.^5-micron membrane filter.
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TABLE 1. IDENTIFICATION OF SLUDGES
Code Number
100
200
300
Uoo
500
600
TOO
800
900
1000
Description
Flue gas desulfurization, lime process,
eastern coal
Electroplating
Nickel/cadmium "battery
Flue gas desulfurization, limestone
process, eastern coal
Flue gas desulfurization, double
alkali process, eastern coal
Flue gas desulfurization, lime
process, western coal
Inorganic pigment production
Chlorine production
Calcium fluoride
Flue gas desulfurization, double
alkali process, western coal
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TABLE 2. IDENTIFICATION OF FIXATION PROCESSES
Process Code Description
A Fly ash and a lime additive, pozzolan
product
B Two additives, soil-like material
C Organic resin, other additives,
and pH adjustment, rubber-like
material
D Plastic encapsulation
E Two commercially available additives,
concrete-like material
F Patented additive and pH adjustment,
clay-like material
G Waste product additive and pH
adjustment, clay-like material
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The methodology used on the fixed sludges involved using a 200 g cured
sample and 800 m£ of deionized water. The subsequent steps vere identical
to the raw sludge elutriate test procedure. All tests were conducted in
triplicate at a constant temperature. After filtering, the centrifugate was
split into two samples. One sample was preserved with nitric acid for metal
analysis and the other sample was preserved by cooling to
TOTAL DIGEST PROCEDURE
A total digest was conducted on samples of the raw and fixed sludges to
develop bulk analysis information. The methodology used in the total digest
procedure is as follows:
a) Place 2 g (wet weight) of sludge in a covered Teflon beaker.
b) Digest at 175°C with a solution of 15 m£ of hydrofluoric acid and 10
mJl of concentrated nitric acid.
c) Evaporate to near dryness, and dissolve the residue in hot 6 N_
hydrochloric acid.
d) Dilute to 100 m£ with deionized water in a volumetric flask. All
tests were conducted in triplicate. Metal analyses were conducted
on all samples.
CHEMICAL ANALYSIS
The methods adopted for chemical analysis were selected by the WES and
reviewed by the USEPA. These methods have been discussed in detail in an
earlier report (5). Table 3 contains a list of the chemical analyses (with
references) conducted on the elutriate samples. Metal analysis methods used
on samples from the total digest test were identical to the methods used on
the elutriate samples.
An extensive quality control program was conducted within the analytical
program. This program included internal, and interlaboratory procedures. A
discussion of the quality control program was included in an earlier report
(5).
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TABLE 3. CHEMICAL ANALYSIS
Cations Anions
Arsenic , Bicarbonate
Beryllium8"' Carbonate
"D^\v»/-v« * r*"h1 rsT*-i Af* *
Chloride
Cadmium ' Cyanide ,
Calciumaa Nitrate^
Chromium, ' Nitrite '
Cobalta'.r Sulfatea'.r
Coppera' Sulfite8"'
T ja,b
Lead ' ,
,, . a,b
Magnesium '
Manganese ' Descriptive
Mercury ,
Molybdenum pH '
Nickel ' , Conductivity
Potassium '
a n
SeleniunL ' Organic
Tin a Chemical oxygen demand '
Vanadium '
Zinca'
Q
Standard Methods for the Examination of Water and Wastevater, 13th Edition.
American Public Health Association, Washington, D. C., 1971.
Methods for Chemical Analysis of Water and Wastes. EPA-625/6-7U-003, U. S.
Environmental Protection Agency, Cincinnati, Ohio, 197U.
Cyanide in Water and Wastewater. Technicon Industrial Method No. 315-T^W,
Technicon Company, Tarrytown, New York,
10
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SECTION 5
ELUTRIATE TEST
ADAPTATION FOR SLUDGES
A modification of the standard elutriate test was chosen as a potential
technique for ascertaining the migration of pollutants from sludges. The major
modification involved the use of deionized water rather than site water.
Also, each elutriate sample was centrifuged to aid in filtering. These modi-
fications resulted in a more reproducible test.
FACTORS AFFECTING THE ELUTRIATE TEST
Studies conducted on the standard elutriate test for dredged materials
have established several factors that could affect the test (6). Those factors
which could affect the elutriate test for sludges include solids-liquid
ratio, pH, time of contact, particle size, and solid-liquid separation. A
discussion of these factors follows.
Solids-Liquid Ratio
A very high or low solids-liquid ratio could result in the elutriate test
yielding low estimates of available contaminants in a sludge sample. For high
solids-liquid ratios, the release of contaminants from the sludge may be
limited by saturation concentrations. If a particular contaminant reaches the
saturation level, a higher solids-liquid ratio would not produce a proportionate
concentration increase in the elutriate. For low solids-liquid ratios, the
amount of contaminants released to the elutriate may not produce a concentration
above the minimum detection limits of standard analytical techniques. Each
contaminant has an optimum release rate corresponding to some particular
solids-liquid ratio due to the concentration of the contaminant in the sludge.
The elutriate test procedure used on the sludges resulted in a solids-liquid
ratio of approximately 1:8 (on a weight basis). This ratio proved to be a good
compromise between the optimum ratios for each contaminant.
EH
The pH of the elutriate is an important controlling factor in the release
of contaminants from a sludge. Generally, solubilities increase with decreasing
pH. In the elutriate test, pH is controlled by the buffer capacity of the
water and sludge. Deionized water used in the test has very little buffer
capacity. Most of the sludges in the study were generated in processes where
pH control is used to minimize metal solubility. The additives used to control
11
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the pH usually result in the sludges having a very high buffer capacity, and
therefore the sludges controlled the pH of the resultant elutriate. This is
also true for the fixed sludges. This difference in buffer capacities in the
elutriate test probably best represents the field situation and therefore no
attempt was made to control the pH of the elutriate during the test.
Time of Contact
The time of contact between the elutriate and sludge is an important
parameter in the elutriate test because the release and migration of contami-
nants is not an instantaneous process. The elutriate test procedure allows
for 30 minutes of contact along with agitation to promote interaction between
the water and sludge. Longer shaking periods were tried but no significant
increases in contaminant concentrations were found in the elutriate.
Particle Size
Particle size associated with each sludge is an important parameter in
the elutriate test because solution is dependent on surface area. Smaller
size particles have a greater surface area per unit weight than do larger
size particles. Therefore, a greater migration of contaminants would be
expected from smaller size particles. In the elutriate test procedure,
several chunks of a particular fixed sludge (approximately 3A inch in diameter)
were placed in an Erlenmeyer flask. This procedure allowed all of the fixed
sludges to start the test with similar surface areas. The raw sludges were
placed in flasks in a thick slurry form resulting in a high surface area-
to-volume ratio. All of the fixed sludges tested deteriorated with many of
them falling completely apart. This situation probably represents the worst
possible field condition. Any attempt at particle size modification such as
grinding and sizing of the sludges would greatly increase the time needed for
conducting the elutriate test. Such a procedure would not represent the
conditions in a disposal site.
Solid-Liquid Separation
Solid-liquid separation in the elutriate test refers to the removal of
solid material from the elutriate. This solids removal is achieved by cen-
trifugation followed by filtration. Centrifugation speeds up the filtering
operation by removing most of the solids. The elutriate test filtration
procedure specifies a 0.1*5 micron membrane filter which is readily available
at a moderate cost. These filters can pass particulate matter in the lower
colloidal size range which will be measured as "soluble" species. Although
particles larger than colloidal size are often found in leachate from sludge
disposal sites, the leachate can usually be filtered before analysis. The
filtering procedure results in a better comparison of the data from the
elutriate test and the analysis of leachate from disposal sites.
Obviously, in any elutriate test procedure, a standard filter type must
be specified and used where results of a series of tests are to be compared.
12
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PRACTICABILITY OF THE ELUTRIATE TEST
The elutriate test was developed to provide a fast, simple testing
procedure at a reasonable cost for evaluating pollutant migration from sludges.
The elutriate test usually requires two days for completion; two to three
hours for the testing procedure and twelve to fourteen hours for the chemical
analysis (depending on the number of parameters). The test can "be performed
by technically trained personnel and equipment normally available in analytical
laboratories. Costs for collection and transportation of sludge samples are
low due to the small amount of material needed for the test. On a cost basis,
the elutriate test is a good alternative for evaluating pollutant migration
from sludges.
There are certain problems concerning the practicability of the elutriate
test that must be addressed in any testing program. The nonhomogeneity of
certain sludges can result in nonreproducible results. The concentrations of
various contaminants in a sludge can vary over a period of time due to operational
changes in the system producing the sludge. In some cases, sludge is placed
in a disposal area along with other materials that can release contaminants
(i.e., bottom ash, domestic wastes, etc). It is important to obtain a representative
sample of sludge if the elutriate test is to provide meaningful results.
Another major problem concerning the practicability of the elutriate test
is the interpretation and application of the results. These results must be
correlated with long-term pollutant migration in a field situation. This
problem will be discussed in detail in the next subsection.
INTERPRETATION AND APPLICATION OF ELUTRIATE TEST RESULTS
The elutriate test was developed for use in ascertaining the migration of
pollutants from sludges. The modeling of actual field conditions at a disposal
site is a difficult and time-consuming process. Since the elutriate test is
not a true analog of a disposal site, various problems arise in the interpretation
of elutriate test results.
It should be noted that the elutriate test is a simple shake test. No
attempt is made in the elutriate test procedure to prevent the physical
deterioration of the sludges. This means that the deionized water used in the
elutriate test is permitted to come in contact with a larger surface area than
it would if the sludges did not fall apart. The elutriate test therefore
gives an indication of the solubility of the pollutants in a particular
sludge. In comparing raw and/or fixed sludges, the elutriate test results
will indicate the success of chemical alterations by the fixation processes
aimed at reducing the solubility of the pollutants.
Many of the fixation processes attempt to limit migration of pollutants
from sludges by chemically altering the physical properties of the sludges in
order to decrease the permeability and surface area-to-volume ratio. These
physical alterations are severely tested in the elutriate test due to the
agitation used in the procedure. In an actual disposal site, the fixed
sludge would usually be placed in such a manner that the permeability of the
13
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fixed sludge mass would "be much less than that of the surrounding soil. In
this situation, the percolating water would travel through the soil until it
contacted the sludge mass. Then the water would flow down the surface of the
fixed sludge mass without deep penetration due to the difference in perme-
abilities of the sludge and the surrounding soil. The elutriate test represents
a "worst case" condition for this type of sludge disposal, that is, a situation
where the sludge mass is fractured or deteriorated in some manner so as to
allow the penetration of percolating water. If the sludge mass does deteriorate
over a period of years, the pollutants will "become more mobile unless their
solubility has been reduced by chemical alteration during the fixation process.
The elutriate test can provide an indication of the success of fixation processes
in reducing the solubility of these pollutants.
The elutriate test is a "one time" test and not a continuous flow test.
The concentrations of pollutants in the elutriate are not necessarily the
concentrations that would be found in leachate from a disposal site. Pollu-
tant concentrations in leachate can vary due to dilution by surrounding
groundwater. Concentrations can also change due to attenuation of certain
pollutants by the soil surrounding the disposal site. The elutriate test
procedure has no provisions for modeling these factors. The pollutant con-
centrations found in the elutriate are dependent on the physical durability of
the sludge sample and on the solubility of the pollutants in the sludge
sample.
The potential of the elutriate test is in its ability to provide a fast,
simple technique for comparing raw and/or fixed sludges. Elutriate test
results provide an indication of the relative effectiveness of different
fixation processes on limiting the migration of pollutants. Elutriate test
data can also indicate which pollutants will be particularly mobile. The
elutriate test can be a very effective aid in evaluating sludge performance
but careful interpretation and application of the results is required.
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SECTION 6
PRESENTATION OF ELUTRIATE TEST RESULTS
CHEMICAL PROPERTIES
The results of the analysis of the elutriate from the elutriate tests
conducted on the raw and fixed sludges are presented in Tables ^ and 5- All
values except for pH and conductivity are expressed in terms of mg/kg on a
dry weight basis. Conductivity is expressed in terms of micromhos/cm. The
conversion of concentrations of parameters to a dry weight basis provides a
common base for comparison of the raw and fixed sludges. This conversion
also results in the multiplication of any error associated with chemical
analysis. The sludges are identified in terms of a three or four digit
number which indicates the source of the sludge (Table l) and a letter which
indicates either a raw sludge (R) or a fixation process (Table 2). The
different combinations of sludges and fixation processes are the result of
fixation processors declining to work with certain sludges.
Table 6 contains the bulk analysis results (metals only) from the total
digest conducted on each sludge. All values have been corrected for blanks
and are expressed in terms of mg/kg on a dry weight basis. The bulk analysis
data along with the elutriate test data was used to calculate the percent
solubilization of certain metals during the elutriate test. This information
is contained in Table 7-
Many of the high concentrations of contaminants reported for the elu-
triate test and the total digest test can be correlated with sludge genera-
tion processes or fixation techniques. Since the exact source of each sludge
and the nature of the fixation additives cannot be disclosed in this report,
correlation between raw and fixed sludge generation and high contaminant
concentrations can be discussed only in general terms.
General Analysis
A general analysis of each elutriate sample was conducted to provide
information concerning pH, organic content, and anion migration from the
sludges (Table U).
COD—
The COD (chemical oxygen demand) is a measure of the oxygen equivalent
of the material in a sample that can be oxidized by a strong chemical oxi-
dant. Although the COD test is designed to reflect the concentration of
organic material in a sample, the oxidation of inorganics such as chloride
15
-------
TABLE 4. ANALYSIS OF ELUTRIATE SAMPLES (GENERAL)
H
o\
Parameters
Sludge
Identification
100R
100A
100B
100E
100F
200R
200A
200B
200C
300R
300A
300B
UOOR
UOOA
UOOB
UOOE
500R
500A
500B
500E
500G
COD
(mg/kg)
230
*5A
BDL
BDL
110
210
80.
310
18000
820
2kO
1*50
500
TU.
160
61.
120
85-
130
68.
BDL
sou
(mg/kg)
7200
6000
11000
720
3100
17000
8800
22000
25000
11000
3800
280
17000
6600
7200
2900
17000
8800
16000
1700
11000
so3
(mg/kg)
6.8,
BDL*
BDL
BDL
160
6.1
100
lUO
97.
12.
87.
160
lU.
55.
UlO
78.
930
68.
260
6A
BDL
N02-N
(mg/kg)
"*'6n
BDL
0.36
BDL
O.U2
0.22
0.10
0.81
BDL
5200
2.U
220
BDL
O.U9
0.20
BDL
1.1
BDL
0.80
BDL
BDL
NO -N
(mg/kg)
0.60
0.08
0.78
BDL
BDL
1.8
BDL
BDL
1.0
88000
1*80
3900
6.2
320
BDL
BDL
0.30
BDL
0.30
BDL
BDL
CH
(mg/kg)
BDL6
BDL
BDL
BDL
3.8
BDL
2.2
11.
0.30
2.8
BDL
0.95
BDL
BDL
BDL
BDL
0.10
BDL
0.30
BDL
BDL
(continued)
-------
TABLE k. (CONTINUED)
Parameters
Sludge
Identification
600R
600A
600B
600E
600F
TOOK
TOOC
800R
800A
800B
900R
900A
900B
1000R
1000A
1000B
1000E
COD
(mg/kg)
190
BDL
BDL
BDL
62.
58.
16000
ll+OO
97.
1100
57.
280
720
21*0
130
180
1*1*.
sou
(mg/kg)
1+2000
5000
1*800
630
5100
2800
29000
8000
1*900
12000
3200
5200
2900
21000
9100
29000
3100
so3
(mg/kg)
33.
6.0
11.
6.7
5.8
3.3
7-0
1.8
BDL
7.3
l*.l*
8.2
Ik.
1500
5.9
1*1*0
8.1
N02-N
(mg/kg)
BDL
BDL
BDL
BDL
0.37
11.
0.12
0.16
1.2
0.73
1.7
0.21*
2.1
0.10
BDL
0.82
0.08
NO -H
(mg/kg)
23.
0.23
0.1*5
BDL
0.21
12.
3.0
0.16
1.1*
0.26
0.30
0.21*
0.13
1.7
0.50
1.1*
BDL
CH
(mg/kg)
BDL
BDL
BDL
BDL
BDL
0.71*
BDL
0.10
0.1*6
BDL
0.10
0.2l*
0.59
0.15
BDL
BDL
BDL
(continued)
-------
TABLE k. (CONTINUED)
oo
Parameters
Sludge
Identification
100R
100A
100B
100E
100F
200R
200A
200B
200C
300R
300A
300B
1*OOR
1*OOA
1*OOB
1*OOE
500R
500A
500B
500E
500G
Cl
(mg/kg)
730
50.
570.
BDL
21*0
380
130
700
80.
1*100
72.
360
70.
BDL
BDL
BDL
ll*00
710
BDL
110
!*50
co3
(mg/kg as
HA*
BDL11
BDL
BDL
BDL
NA
BDL
BDL
BDL
NA
BDL
3000
NA
BDL
570
BDL
NA
BDL
BDL
BDL
BDL
CaCO )
NA
1300
210
720
980
NA
ll+OO
3200
BDL
NA
1*80
BDL
NA
500
BDL
290
NA
2700
BDL
2200
2500
pH
7-0
7-0
8.1
7.1*
7.1
7.2
7-5
7.8
5-2
11.1*
7.0
11.6
7-9
7-3
12.1
6.9
12.6
6.7
12.1
9.8
6.9
Conductivity
(X10 micromhos/cm)
1.6
2.5
2.9
1.5
2.2
3.0
3.2
5.1*
6.2
3.1
2.0
1*.9
1.6
2.1*
7.3
1.1*
7.0
3.6
13.5
2.6
5.1*
(continued)
-------
TABLE it. (CONTINUED)
H
VO
Parameters
Sludge
Identification
600R
600A
600B
600E
600F
700R
TOOC
800R
800A
800B
900R
900A
900B
1000R
1000A
1000B
1000E
Cl
(mg/kg)
3100
97.
730
BDL
330
BDL
98.
2l»000
5500
kkooo
BDL
BDL
BDL
660
89
BDL
77.
co3
(mg/kg
NA
BDL
BDL
BDL
BDL
NA
BDL
NA
BDL
130
NA
BDL
BDL
NA
BDL
1100
1100
HC03
as CaCO_)
NA
1100
3000
1300
1700
NA
Wo
NA
1900
3^00
NA
1600
2100
NA
2700
BDL
BDL
pH
7.3
6.8
6.7
6.8
7.1
7-3
6.0
8.2
7.2
8.6
7-1
7.1
7.3
9-1
6.9
12.lt
10.2
Conductivity
•3
(X10 micromhos/om)
1.8
2.1*
2.0
0.9
3.1
1.7
6.5
2.1
5.8
2k. 8
1.3
2.!+
l.lt
8.3
3.6
15.3
2.2
a<5
*<1
C <0.01
d
-------
TABLE 5- ANALYSIS OF ELUTRIATE SAMPLES (METALS)
ro
o
Metals
Sludge
Identification
100R
100A
100B
100E
100F
200R
200A
200B
200C
300R
300A
BOOB
1+OOR
1+OOA
1+OOB
1+OOE
500R
500A
500B
500E
500G
As
(nig/kg)
1.3.
BDLa
0.1+2
0.09
0.06
BDL
0.08
0.008
0.06
0.03
0.01
0.009
0.09
0.02
0.0k
0.07
0.03
0.19
0.02
0.15
0.31
B
(mg/kg)
HDAfc
9-6
5.2
1.1*
8.0
NBA
23.
2.3
8.8
NBA
20.
0.26
NDA
20.
O.Ik
1.6
NDA
lit.
O.TO
0.82
37.
Be
(mg/kg)
BDLC
0.03
0.06
0.01
0.02
0.15
0.01+
0.07
5.2
BDL
0.007
0.002
BDL
0.001+
0.003
0.002
BDL
0.006
0.005
0.003
0.009
Ca
(mg/kg)
1+900
ll+OO
21+00
1+1+0
2000
2700
21+00
2600
630
71+ .
1100
28.
9600
2200
510
1200
1+800
2900
1900
220
3100
Cd
(mg/kg)
0.11
0.16
0.06
0.01
0.01
0.39
0.38
0.59
25.
0.75
220
1.0
0.01
0.13
0.008
0.03
0.008
0.07
0.008
0.003
0.009
Cr
(mg/kg)
0.08
0.25
0.75
0.03
0.008
0.69
3.9
59.
21.
0.20
0.21
0.13
0.11+
0.1+0
0.1+3
0.18
0.11
0.17
0.1+2
0.29
0.009
Cu
(mg/kg)
0.33
0.81
0.63
0.01+
0.39
16.
1+.7
13-
1200
0.61
0.06
0.11
0.29
0.19
0.10
0.02
0.13
0.06
0.23
0.03
0.07
Mg
(mg/kg)
BDLd
BDL
BDL
BDL
BDL
BDL
BDL
BDL
BDL
BDL
BDL
BDL
BDL
BDL
BDL
BDL
BDL
BDL
BDL
BDL
BDL
(continued)
-------
TABLE 5. (CONTINUED)
ro
Metals
Sludge
Identification
600R
600A
600B
600E
600F
TOOR
TOOC
800R
800A
800B
900R
900A
900B
1000R
1000A
1000B
1000E
As
(mg/kg)
0.12
0.01
o.oi*
0.009
0.87
BDL
BDL
BDL
0.11
o.oi*
BDL
0.07
0.02
0.03
0.02
0.03
0.09
B
(mg/kg)
NDA
7.8
It. 6
1.3
10.
NDA
1*3.
NDA
23.
0.32
NDA
25.
1.0
NDA
11.
2.1
0.69
Be
(mg/kg)
BDL
0.009
0.009
0.009
0.01
BDL
0.01
BDL
0.009
0.008
BDL
O.OOl*
0.00k
BDL
O.OOl*
0.01
0.002
Ca
(mg/kg)
19000
1600
2200
600
3600
580
1100
1100
2900
930
1300
3300
1600
390
21*00
220
280
Cd
(mg/kg)
0.06
0.28
0.1*5
0.01
0.003
2.1
ll+O
0.05
150
0.18
o.ool*
0.005
0.03
0.02
0.02
0.03
0.01
Cr
(mg/kg)
0.1*0
0.21
0.1*2
0.13
0.21
0.08
1.7
0.1(8
0.23
1-7
0.007
0.20
0.20
0.03
0.21
0.66
0.52
Cu
(mg/kg)
0.05
0.05
0.21*
0.01
0.02
0.11
1*.5
0.33
0.39
0.22
o.ool*
1.1*
26.
0.10
0.10
0.1*7
0.36
Hg
(mg/kg)
BDL
0.001
BDL
BDL
0.001
BDL
BDL
0.03
0.003
o.ooi*
BDL
BDL
BDL
BDL
BDL
BDL
BDL
(continued)
-------
TABLE 5- (CONTINUED)
ro
ro
Sludge
Identification
100R
100A
100B
100E
100F
200R
200A
200B
200C
300R
300A
300B
1*OOR
UOOA
1*OOB
UOOE
500R
500A
500B
500E
500G
K
(mg/kg)
NBA
U7.
900
360
28.
NDA
ll*0
220
12.
NDA
150
210
NDA
89-
690
330
NDA
31*0
720
360
2600
Mg
(mg/kg)
7U.
13.
12.
12.
29.
630
16.
11.
510
1.9
11.
0.55
97.
7.1*
0.8l
10.
0.83
6.8
0.20
2.2
270
Mn
(rag/kg)
0.73
0.72
0.72
0.12
2.8
U.I
0.99
1.5
11.
BDL6
0.26
0.10
0.55
0.36
0.37
0.22
0.0k
0.71
0.03
0.02
6.1
Mo
(mg/kg)
NDA
0.93
1.3
0.26
0.85
NDA
1.3
1.2
0.66
NDA
0.62
BDL
NDA
2.1
BDL
0.6l
NDA
2.3
1.6
BDL
0.98
Metals
Na
(mg/kg)
NDA
1500
2000
100
lUo
NDA
1300
7000
1*700
NDA
890
5200
NDA
300
5200
180
NDA
2700
13000
1600
2300
Ni
(mg/kg)
2.2
0.19
0.26
0.03
0.18
l*.l
0.56
0.8U
120
2.1*
12.
2.6
0.70
0.1*5
0.22
0.05
0.18
0.23
0.08
0.02
0.19
Pb
(mg/kg)
o.oi*
0.07
o.oi*
0.01
O.OU
0.02
0.25
0.7l*_
BDLg
0.03
BDL
0.02
0.15
0.03
0.02
o.oi*
0.02
0.03
0.03
0.02
0.02
Se
(mg/kg)
0.05
0.10
O.ll*
0.09
0.08
0.05
0.07
0.12
0.09
0.10
0.08
0.10
0.10
0.05
0.09
0.05
0.10
0.08
0.1*3
0.07
0.09
Zn
(mg/kg)
0.21
0.50
BDLh
BDL
BDL
7-8
6.2
5.0
330
0.26
0.39
BDL
7.3
BDL
BDL
BDL
BDL
0.1*3
BDL
BDL
BDL
(continued)
-------
TABLE 5- (CONTINUED)
ro
u>
Metals
Sludge
Identification
600R
600A
600B
600E
600F
700R
700C
800R
800A
800B
900R
900A
900B
1000R
1000A
1000B
1000E
K
(mg/kg)
NDA
26.
210
93.
160
NDA
15.
NDA
150
250
NDA
130
260
NDA
55-
1*70
270
Mg
(mg/kg)
820
20.
15-
7.0
28.
1*20
1300
33.
12.
3.0
130
1*2.
17-
89-
31.
0.21
U.2
Mn
(mg/kg)
19.
0.23
1.7
0.17
2.2
5.U
150
0.37
O.Ik
0.21*
0.67
0.67
0.22
BDL
0.38
0.03
0.07
Mo
(mg/kg)
NDA
1.2
1.5
BDL
.87
NDA
BDL
NDA
l.k
BDL
NDA
2.1
BDL
NDA
1.3
BDL
BDL
Na
(mg/kg)
NDA
190
1600
130
IkO
NDA
5600
NDA
2600
31000
NDA
2100
780
NDA
2100
20000
1500
Ni
(mg/kg)
2.5
0.15
0.19
O.OU
0.11
O.lU
3.7
0.05
6.0
0.20
0.62
0.51
7.3
0.07
0.12
0.23
0.16
Fb
(mg/kg)
BDL
0.02
0.20
0.02
BDL
0.51
30.
0.01
0.02
0.07
0.02
BDL
0.10
0.03
5.5
0.22
0.01
Se
(mg/kg)
0.37
0.22
O.lU
0.06
0.07
0.01
0.11
o.oU
0.09
0.16
0.01
0.11
O.lU
0.08
0.12
0.17
0.10
Zn
(mg/kg)
l.U
BDL
BDL
O.UU
BDL
BDL
16.
BDL
BDL
BDL
0.10
0.58
O.U6
O.lU
BDL
BDL
0.28
& <0.002
No data available
C <0.001
d <0.0002
e <0.003
f
g
h
-------
TABLE 6. ANALYSIS OF TOTAL DIGEST (METALS)
IV)
Metals
Sludge
Identification
100R
100A
100B
100E
100F
200R
200A
200B
200C
300R
300A
300B
UOOR
UOOA
UOOB
UOOE
UOOG
500R
500A
500B
500E
500G
As
(mg/kg)
170
60.
56.
25.
2.1
2k.
29.
13.
2.6
BGSa
30.
0.20
35.
UU.
13.
Ul.
5.U
150
73
120
19.
38.
Be
(mg/kg)
12.
8.5
U.3
2.5
1.6
8UO
98.
320
72.
BDLb
7.8
BDL
6.1
6.9
BDL
1.9
0.78
3.9
9.0
BDL
2.5
1.1
Ca
(mg/kg)
63000
31*000
1*3000
60000
81*000
75000
58000
1*5000
20000
37000
21*000
1*7000
160000
63000
1*2000
110000
180000
69000
93000
190000
1*6000
150000
Cd
(mg/kg)
2.U
BGS
8.0
7.5
5-2
1800
320
730
130
520000
110000
1*90000
13.
26.
20.
U.I*
BGS
22.
BGS
1*3.
6.9
BGS
Co
(mg/kg)
U7.
29.
27.
21.
11.
120
U5.
66.
1U.
150
37.
180
35.
22.
11.
16 V
BDLC
22.
28.
1U.
19.
BDL
Cr
(mg/kg)
99.
85.
90.
60.
27.
150000
2UOOO
85000
20000
180
89.
110
91.
63.
36.
1*8.
21.
5U.
62.
3U.
53.
1U.
Cu
(mg/kg)
88.
68.
51.
35.
26.
95000
12000
55000
9800
1300
130
360
170
75.
U5.
33.
1U.
92.
78.
50.
1*6.
16.
Hg
(mg/kg)
0.82
0.31
0.50
O.l6
0.05
0.53
0.20
0.26
O.OU
9.8
0.69
lU.
1.9
0.39
O.U1*
0.33
0.08
1.6
0.83
1.8
0.16
0.2U
(continued)
-------
TABLE 6. (CONTINUED)
ro
V/l
Metals
Sludge
Identification
600R
600A
600B
600E
600F
600G
TOOR
700C
800R
800A
800B
900R
900A
900B
1000R
1000A
1000B
1000E
1000G
As
(mg/kg)
29.
7.0
19.
8.4
fc9.
17.
100.
.58
BGS
52.
1.6
BGS
1U.
0.73
13.
7.2
lt.1
18.
17-
Be
(mg/kg)
27.
It. 2
1-9
1.7
!*.2
0.68
BDL
BDL
BDL
5.»»
BDL
BDL
6.3
BDL
BDL
3-0
BDL
1.1.
BDL
Ca
(mg/kg)
200000
67000
51(000
57000
50000
180000
1*0000
3900
27000
110000
120000
1*6000
120000
170000
59000
69000
120000
57000
180000
Cd
(mg/kg)
18.
BGS
7.6
7.2
>*.7
BGS
9700
1100
2.7
BGS
9-8
5.5
BGS
7.3
2.3
BGS
5.1
21.
BGS
Co
(mg/kg)
83.
16.
29.
16.
15-
BDL
13.
BDL
BDL
19.
BDL
23.
23.
9.0
HDL
12.
27.
16.
BDL
Cr
(mg/kg)
130
21*.
1*3.
33.
67.
52.
110000
12000
9-3
38.
.65
3k.
59-
20.
25.
27.
ll*.
55-
12.
Cu
(mg/kg)
280
51.
77-
25.
30.
ll*.
7600
670
260
160
220
670
220
1*80
38.
50.
21*.
35.
12.
Hg
(mg/kg)
O.ll*
0.22
0.1*5
0.06
0.10
0.03
38.
6.5
67.
38.
71*.
0.06
0.21*
0.31
0.08
0.17
0.31
0.10
0.09
(continued)
-------
TABLE 6. (CONTINUED)
OS
Sludge
Identification
100R
100A
100B
100E
100F
200R
200A
200B
200C
300R
300A
300B
1*OOR
UOOA
1*OOB
1*OOE
1*OOG
500R
500A
500B
500E
500G
Mg
(mg/kg)
5500
2300
350
550
2100
5700
31*00
1*1*00
1200
6000
3200
1000
18000
5UOO
1*800
3800
3100
9700
5UOO
6800
690
2700
Mn
(mg/kg)
160
120
61*0
370
250
390
150
690
BGS
370
110
550
250
120
590
360
lUo
170
150
1*60
290
100
Mo
(mg/kg)
21*.
1*3.
36.
25.
37.
77.
62.
21.
26.
15.
51.
15.
150
53.
78.
35.
9.1*
99-
71.
23.
17.
19.
Na
(mg/kg)
17000
20000
19000
1*1*00
5900
1*9000
28000
19000
8600
29000
23000
20000
1*0000
25000
16000
8200
20000
28000
31000
12000
5600
20000
Metals
Ni
(mg/kg)
ll*0
68.
76.
32.
21.
6100
1100
3600
670
390000
37000
360000
220
7»*.
50.
27-
19.
120
66.
83.
1*3.
12.
Pb
(mg/kg)
81*.
61.
52.
18.
31*.
ll*00
1*50
880
2UO
590
70.
180
100
51.
28.
30.
89.
160
91-
71*.
ll*.
61*.
Sn
(mg/kg)
26.
38.
25.
6.2
7.7
22000
3500
10000
2500
390
28.
150
39.
!*!*.
21.
BGS
BGS
28.
26.
29.
BGS
BGS
V
(mg/kg)
270
180
120
80.
1+0.
82.
210
62.
15.
20.
200
9.9
290
190
1*7.
62.
95.
ll*0
200
28.
97.
1*7.
Zn
(mg/kg)
170
110
110
59.
1*6.
18000
2600
10000
2000
3800
260
850
330
110
90.
71.
91*.
230
lUo
160
73.
89.
(continued)
-------
TABLE 6. (CONTINUED)
ro
Sludge
Identification
600R
600A
600B
600E
600F
600G
700R
700C
800R
800A
800B
900R
900A
900B
1000R
1000A
1000B
1000E
1000G
Mg
(mg/kg)
31*000
7800
ll*00
270
2200
2200
60000
3200
1700
2900
160
7800
7700
53000
5200
8800
3200
1300
2600
Mn
(mg/kg)
600
110
920
320
270
150
31*00
310
82.
110
250
220
160
350
1*1*.
88.
360
260
120
Mo
(mg/kg)
ll*0
68.
67-
33.
1*1.
8.5
5700
390
15.
55.
1*0.
BGS
65.
31.
5-7
^5.
51.
31.
21*.
Na
(mg/kg)
100000
26000
15000
5l*00
7600
23000
20000
5200
11000
26000
11000
25000
23000
22000
19000
29000
15000
6300
26000
Metals
Ni
(mg/kg)
210
32.
60.
30.
1*0.
11.
700
71.
30.
50.
22.
880
270
690
50.
25.
20.
1*8.
8.8
Pb
(mg/kg)
380
61.
85-
18.
22.
72.
160000
150
110
85-
70.
370
170
330
93.
51.
1*9-
15.
61.
Sn
(mg/kg)
81*.
3.8
1*8.
7-7
11.
BGS
11*000
ll*00
16.
BGS
3.5
98.
21*.
60.
19.
BGS
10.
5-5
BGS
V
(mg/kg)
530
ll*0
110
50.
100
61.
120
20.
38.
ll*0
12.
67.
180
33.
69.
ll*0
35.
1*9.
59.
Zn
(mg/kg)
31*0
80.
100
69.
75.
66.
3800
1*10
78.
85.
91.
560
280
520
67.
77.
1*7.
1*5.
56.
Blank greater than sample
<0.01
-------
TABLE 7. METAL SOLUBILIZATION
ro
CO
Sludge
Identification
100R
100A
100B
100E
100F
200R
200A
200B
200C
300R
300A
300B
UOOR
UOOA
UOOB
UOOE
500R
500A
500B
500E
500G
As
0.76a
NC
0.75
0.36
2.9
NC
0.28
0.06
2.3
NC
0.03
U.5
0.26
0.05
0.31
0.17
0.02
0.26
0.02
0.79
0.82
Be
NCb
0.35
l.U
o.Uo
1.3
0.02
O.OU
0.02
7.2
NC
0.09
NC
NC
0.06
NC
0.11
NC
0.07
NC
0.12
0.82
Metals
Ca
7.8
U.I
5.6
0.73
2.1+
3.6
U.l
5.8
3.2
0.20
U.6
0.06
6.0
3.5
1.2
1.1
7.0
3.1
1.0
O.U8
2.1
Cd
U.6
NC
0.75
0.13
0.19
0.02
0.12
0.08
19.2
<0.01
0.20
<0.01
0.08
0.50
o.oU
0.68
O.OU
NC
0.02
o.oU
NC
Cr
0.08
0.30
0.83
0.05
0.03
<0.01
0.02
0.07
0.11
0.11
0.2U
0.12
0.15
0.63
1.2
0.38
0.20
0.27
1.2
0.55
0.06
Cu
0.38
1.2
1.2
0.11
1.5
0.02
O.OU
0.02
12.2
0.05
0.05
0.03
0.17
0.25
0.22
0.06
O.lU
0.08
O.U6
0.07
o.oU
(continued)
-------
TABLE 7. (CONTINUED)
ro
vo
Metals
Sludge
Identification
600R
600A
600B
600E
600F
700R
700C
800R
800A
800B
900R
900A
900B
1000R
1000A
1000B
1000E
As
O.Ul
O.lU
0.21
0.11
1.8
NC
NC
NC
0.21
2.5
NC
0.50
2.7
0.23
0.28
0.73
0.50
Be
NC
0.21
0.1*7
0.53
0.21*
NC
NC
NC
0.17
NC
NC
0.06
NC
NC
0.13
NC
O.lU
Ca
9-5
2.1*
U.I
1.1
7.2
1.5
28.2
U.I
2.6
0.78
2.8
2.8
0.9U
0.66
3.5
0.18
0.1*9
Cd
0.33
NC
5-9
O.lU
0.06
0.02
12.7
1.9
NC
1.8
0.07
NC
0.1*1
0.87
NC
0.59
0.05
Cr
0.31
0.88
0.98
0.39
0.31
<0.01
0.01
5-2
0.6l
>100
0.02
0.3U
1.0
0.12
0.78
U-7
0.95
Cu
0.02
0.10
0.31
o.oU
0.07
<0.01
0.67
0.13
0.2U
0.10
<0.01
0.6U
5-U
0.26
0.20
2.0
1.0
(continued)
-------
TABLE 7. (CONTINUED)
(jO
o
Sludge
Identification
100R
100A
100B
100E
100F
2 OCR
200A
200B
200C
300R
300A
300B
1*OOR
UOOA
1*OOB
UOOE
500R
500A
500B
500E
500G
Mg
1.3
0.57
3.!*
2.2
1.1*
11.1
0.1*7
0.25
1*2.5
0.03
0.31*
0.06
0.51*
O.ll*
0.02
0.26
0.01
0.13
<0.01
0.32
10.0
Mn
0.1*6
0.60
0.11
0.03
1.1
1.1
0.66
0.22
NC
NC
0.21*
0.02
0.22
0.30
0.06
0.06
0.02
0.1+T
0.01
0.01
6.1
Mo
NC
2.2
3.6
1.0
2.3
NC
2.1
5.7
2.5
NC
1.2
NC
NC
i*.o
NC
1.7
NC
3.2
7.0
NC
5.2
Metals
Na
NC
7-5
10.5
2.3
2.1*
NC
1*.6
36.8
51*. 7
NC
3.9
26.
NC
1.2
32.5
2.2
NC
8.7
>100
28.6
11.5
Ni
1.6
0.28
0.31*
0.09
0.86
0.07
0.05
0.02
17-9
<0.01
0.03
<0.01
0.32
0.6l
0.1*1*
0.19
0.15
0.35
0.10
0.05
1.6
Fb
0.05
0.11
0.08
0.06
0.12
<0.01
0.06
0.08
NC
0.01
NC
0.01
0.15
0.06
0.07
0.13
0.01
0.03
o.oi*
O.ll*
0.03
Zn
0.12
0.1*5
NC
NC
NC
o.oi*
0.21*
0.05
16.5
0.01
0.15
NC
2.2
NC
NC
NC
NC
0.31
NC
NC
NC
(continued)
-------
TABLE 7. (CONTINUED)
Sludge
Identification
600R
600A
600B
600E
600F
700R
700C
800R
800A
800B
900R
900A
900B
1000R
1000A
1000B
1000E
Mg
2.1*
0.26
1.1
2.6
1.3
0.70
1*0.6
1.9
0.1*1
1.9
1.7
0.55
0.03
1.7
0.35
0.01
0.32
Mn
3.2
0.21
0.18
0.05
0.81
O.l6
1*8.1*
0.1*5
0.13
0.10
0.30
0.1*2
0.06
NC
0.1*3
0.01
0.03
Mo
NC
1.8
2.2
NC
2.1
NC
NC
NC
2.5
NC
NC
3.2
NC
NC
<0.01
NC
NC
Metals
Na
NC
0.73
10.7
2.1*
1.8
NC
>100
NC
10.0
>100
NC
9-1
3-5
NC
7.2
>100
23.8
Ni
1.2
0.1*7
0.32
0.13
0.28
0.02
5.2
0.17
12.0
0.91
0.07
0.19
1.1
O.ll*
0.1*8
1.2
0.33
Pb
NC
0.03
0.21*
0.11
NC
<0.01
20.0
0.01
0.02
0.10
0.01
NC
0.03
0.03
10.8
0.1*5
0.07
Zn
0.1*1
NC
NC
0.61*
NC
NC
3.9
NC
NC
NC
0.02
0.21
0.09
0.21
NC
NC
0.62
*
All values expressed in percent
Not calculated
-------
and nitrite can result in artifically high values.
The data from the elutriate test indicated high COD values for fixed
sludges 200C and 700C. Fixation process C involves an organic resin which
probably resulted in the release of organic carbon to the elutriate. These
high COD values for process C indicated that material was moving out of the
fixed sludges to the elutriate.
High COD values for sludges 300R and 800R and fixed sludge 800B probably
resulted from chloride ion interference. Sludge 800R was a brine sludge from
a chlorine production process and had a high concentration of chloride ions.
Analysis of the elutriate from sludge 300R also indicated a large nitrite
concentration which could interfere with the COD determination.
COD values for the elutriate from the raw and fixed sludges indicated
that fixation generally reduced the migration of materials that could be
oxidized by a strong chemical oxidant.
Sulfate and Sulfite—
Sulfate and sulfite were the predominant anionic species in the elutriate
from the sludges except for sludge 800 (chlorine brine sludge). The generation
of sulfates and sulfites can be expected in FGD sludge production. Many of the
industrial processes also involve the use of or generation of some form of
sulfur compound. Sulfate and sulfite ions were also introduced into the fixed
sludges from certain fixation additives which contain high concentrations of
sulfate.
The predominance of sulfate ions in the elutriate was probably due to air
oxidation of sulfite ions in sludge holding ponds and in the elutriate sample.
Elutriate samples from sludges 500R and 1000R had much higher sulfite concen-
trations than the other samples. The high sodium concentrations in these
double alkali FGD sludges probably resulted in soluble sodium sulfite being
leached from the sludges.
Both sulfate and sulfite concentrations in the elutriate were highly
variable. From the available data, fixation process E proved to be the most
successful at retarding the migration of sulfate and sulfite to the elutriate.
Process A also provided some attenuation of sulfate and sulfite while other
processes included in the study proved only partly successful.
Nitrite and Nitrate—
Only small amounts of nitrite and nitrate were found in the elutriate
from the sludges except for sludge 300. Elutriate from sludge 300R and fixed
sludge 300B contained high levels of both nitrite and nitrate. Fixed sludge
300A produced a high concentration of nitrate in the elutriate.
Sludge 300 was generated in a nickel/cadmium battery process where
nitrate salts of nickel and cadmium are used as raw materials (7). Any
metallic cadmium remaining in the waste stream could reduce nitrate to nitrite
(8). This reaction was probably the source of the nitrite found in the sludges.
32
-------
Fixed sludge kOOA. resulted in a high nitrate concentration in the elutri-
ate, but from the available data this value appears to be an anomaly. Overall,
the fixation processes were generally successful in reducing the migration of
nitrite and nitrate to the elutriate.
Cyanide—
The elutriate from the FGD sludges (100, UOO, 500, 600, and 1000) con-
tained very little cyanide. Cyanide was formed in appreciable amounts in the
elutriate from the fixed samples of sludge 200, sludge 300R, and fixed sludge
100F. Sludge 200 was generated in an electroplating process where cyanide
baths are used to hold plating ions in solution. As a result, the low value
for cyanide in the elutriate of sludge 200R may be considered questionable.
Cyanide is also used in the nickel/cadmium battery production process
which probably resulted in residual cyanide in sludge 300R. The concentration
of cyanide in fixed sludge 100F along with other fixed sludges may have been
the result of addition of cyanide-containing fixation additives. The data
indicated no significant trends in the attenuation of cyanide by the various
fixation processes.
Chloride—
Chloride concentrations in the elutriate of the sludges were highly
variable. The elutriate from sludge 800R had a high concentration of chlo-
ride. This was as expected since the sludge was generated in a chlorine
production process using a brine. Fixed sludge 800A resulted in a low con-
centration of chloride indicating that fixation process A was successful in
limiting chloride migration. The elutriate from fixed sludge 800B had a
higher concentration of chloride than did the elutriate from sludge 800R.
The higher concentration probably resulted from the addition of chloride by a
fixation additive or an addition of a contaminant in the fixation additives
which helped to solubilize the chloride. For certain other sludges, fixation
process B was able to limit chloride migration. Other fixation processes
were generally successful in reducing chloride concentrations in the elutriates.
Carbonate and Bicarbonate—
The carbonate/bicarbonate determination was essentially a measure of the
alkalinity of the elutriate. The particular form (carbonate or bicarbonate)
found in the elutriate was pH dependent. At lower pH values, the bicarbonate
form was predominant and at higher pH values the carbonate form was predominant.
Bicarbonate salts of metals are generally more soluble than are carbon-
ate salts. For example, calcium carbonate can be leached from limestone in
the form of calcium bicarbonate by the action of water rich in dissolved car-
bon dioxide. Other metals can react similarly. In terms of metal migration
from sludges, it is therefore important to maintain a sufficiently high pH
for predominance of the less soluble carbonate salt.
Carbonate/bicarbonate concentrations in the elutriates of the fixed
sludges were generally high. Since carbonate/bicarbonate analyses were not
conducted on the raw sludges, no comparison can be made with the fixed sludges.
33
-------
pH—
pH is an important parameter in determining the solubility of metals.
Metals are generally more soluble at low pH values and less soluble at high
pH values. Metal hydroxides exhibiting an amphoteric character (e.g., Be,
Cu, Cr, Al, Zn, etc) do not follow this general rule (9). They form complexes
at high pH values which result in increased solubility.
The pH values of the elutriate varied from the acidic to the strongly
basic range. The lowest pH values were associated with fixation process C.
A low pH must be maintained in the process C fixation procedure to force the
fixation reaction to occur. The highest pH values were associated with
sludges produced in processes that involved the use of sodium hydroxide
(sludges 300, 500, 800, and 1000).
The fixation processes varied greatly in their ability to maintain or
increase the pH of the elutriate. A decrease in pH was in general considered
undesirable due to the resulting mobilization of metals. The metal analyses
indicated a correlation between low pH values and metal mobilization but very
little correlation between high pH values and metal immobilization.
Conductivity—
Specific conductivity is a measure of the total ionic concentration in a
sample. The optimum pH range for conductivity determinations is between six
and nine. The conductivities due to hydrogen ions and hydroxyl ions are much
greater than those due to other ions and therefore will produce invalid
results when the pH of a sample is outside the optimum range (8). Therefore,
elutriate samples with high pH values (300R, 300B, UOOB, etc) could not be
compared on the basis of conductivities.
The conductivities of the elutriates of the sludges with sample pH in the
optimum range are highly variable. The data indicated that fixation processes
were capable of limiting the migration of contaminants only for certain sludges.
All of the fixation processes on sludge 600 were successful in reducing specific
conductivity- For other sludges, success was dependent on the fixation process.
The specific conductivity provided only a limited overall view of the success
or failure of the fixation processes used on the various sludges.
Metal Analysis
As mentioned previously, a large number of metal analyses were conducted
on the elutriate from the sludges (Table 5). Many of the same metal analyses
were conducted on the samples generated in the total digest tests (Table 6).
Data from the two tests was used to determine percent solubilization for
certain metals (Table 7).
Arsenic—
High arsenic levels were indicated in the total digest test for sludges
100R, 500R, and TOOK and for fixed sludge 500B. Sludges 100 and 500 are FGD
sludges from power plants burning eastern coal. This coal'is probably the
source of the arsenic. Sludge TOO is an inorganic pigment production sludge.
Some form of arsenic is probably used in or found as a contaminant in the
pigment production process.
34
-------
The elutriate from sludge 100R had a high arsenic concentration corre-
sponding to the bulk analysis, but sludges 500R and TOOK did not. The solubi-
lization of arsenic in the elutriate test was generally low with most values
being under one percent.
Boron—
Boron analyses were conducted on the elutriate from the fixed sludge
samples. Elutriate samples from sludges fixed by process A generally con-
tained higher boron concentrations than samples from sludges fixed by the
other processes. Elutriate from certain sludges fixed by processes C, F, and
G had high boron concentration, but not as high as those from process A. It
is possible that certain additives for processes A, F, and G contain boron as
a contaminant.
Beryllium—
Sludge 200R and fixed sludges 200A, 200B, and 200C were shown to contain
high levels of beryllium in the total digest test. Sludge 200 is produced in
an electroplating process. Some mobilization of beryllium was indicated in
the elutriate test for sludge 200R. The elutriate test for fixed sludge 200C
indicated a fairly high mobilization of beryllium which probably resulted from
the low pH associated with fixation process C. It should be noted that the
differences in beryllium concentrations for the raw and fixed sludges were a
result of lowering the detection limit for beryllium after the analysis of
elutriate samples from the raw sludges was conducted.
The solubilization of beryllium in the elutriate test was generally low
except for fixed sludge 200C.
Calcium—
High calcium concentrations were indicated in each sludge by the total
digest test. Lime, lime derivatives, and other compounds of calcium are used
in most of the processes in which the sludges are generated as either a treatment
step or as an integral part of an industrial process. Some of the additives
used in the fixation processes also contain calcium compounds. Calcium con-
centrations in the elutriates were generally high. These values are probably
strongly dependent on the amount of excess lime or other calcium compounds
used.in a particular process and the form of calcium contained in the sludge
(i.e., sulfate, sulfite, carbonate, etc). Calcium solubilization in the
elutriate test was generally in the range of 1 to 10 percent.
Cadmium—
Bulk analysis data indicated high cadmium concentrations in raw and fixed
samples of sludges 200, 300, and 700. Sludge 200 (electroplating), sludge 300
(nickel/cadmium battery), and sludge TOO (inorganic pigment) are produced in
processes that use cadmium. Cadmium was not mobilized in the elutriate test
except for fixed sludges 200C, 300A, TOOC, and 800A. The high concentrations
of cadmium in the elutriate samples for sludges fixed by process C were probably
a result of the low pH associated with process C. Since the concentration of
cadmium in the elutriate of fixed sludge 800A is higher than the total digest
concentration, it may be assumed that the samples used in the two tests were
not homogeneous. The high cadmium value in the elutriate of fixed sludge 300A
appears too high when compared with sludges 300R and 300B. This same situation
35
-------
occurred for certain other metal analyses for fixed sludge 300A.
Solubilization of cadmium in the elutriate test was generally low. Only
sludges 100R and 800R and fixed sludges 200C, 600B, TOOC, and 900B had solu-
bilization rates greater than one percent.
Cobalt—
Cobalt analyses were conducted on samples from the total digest test.
Varying amounts of cobalt were found in the sludges with the highest concen-
trations being in sludges 200R (electroplating) and 300R (nickel/cadmium bat-
tery) and fixed sludge 300B. The higher concentrations in these sludges is
probably the result of cobalt contamination of metals used in the two electro-
plating processes.
Chromium—
High chromium concentrations were indicated in both raw and fixed sludges
for sludge series 200 (electroplating) and TOO (inorganic pigment). Signifi-
cant mobilization of chromium was indicated by the elutriate test results for
fixed sludges 200B and 200C. Most of the fixation processes were not successful
in limiting the migration of chromium in the elutriate test. High pH associated
with some of the fixation processes may help mobilize chromium since the
hydroxide of chromium is amphoteric.
The solubilization of chromium in the elutriate test was generally less.
than one percent. The extremely high value for 800B may indicate an anomalous
value for the elutriate test or the total digest test. This difference could
also have resulted from nonhomogeneous samples of sludge being used in the
tests.
Copper—
Copper was found in all the sludges with the highest concentrations being
found in sludge series 200 (electroplating) and 700 (inorganic pigment).
Mobilization of copper in the elutriate test was high for all the sludges in
sludge series 200 and for fixed sludges TOOC and 900B. Copper solubilization
was less than two percent except for fixed sludges 200C and 900B.
Mercury—
Mercury concentrations were generally low in the total digest test except
for sludges in sludge series 300 (nickel/cadmium battery), TOO (inorganic
pigment), and 800 (chlorine production). The highest concentrations of mer-
cury were found in sludges in sludge series 800 where a mercury cell is used
in the production process.
Mercury mobilization in the elutriate test was very low with most of the
concentrations being below the detectable limit of the analytical equipment
used.
Potassium—
Potassium analyses were conducted on elutriate from the fixed sludge
samples. Varying concentrations of potassium were found in the elutriate from
the fixed sludges but in most cases, the elutriate from sludges fixed by
process B had the highest potassium concentrations. These high concentrations
36
-------
in the elutriate samples vere probably the result of a high potassium concen-
tration in one of the fixation additives for process B. The elutriate from
the one sludge fixed by process G also had a very high potassium concentration.
Magnesium—
High concentrations of magnesium were indicated in both raw and fixed
sludges by the total digest test. Magnesium is a common contaminant in
limestone and other naturally occurring calcium compounds. As mentioned
previously, most of the sludges are produced in processes where some calcium
compound is used and therefore magnesium is introduced into the process as a
contaminant.
Magnesium mobilization in the elutriate test was significant for sludges
200R, 600R, and 700R and for fixed sludges 200C, 500G, and TOOC. Solubili-
zation of magnesium was generally low except for fixed sludges 200C and TOOC.
The low pH associated with process C produced a solubilization of approxi-
mately Uo percent for both sludges.
Manganese—
Manganese concentrations in the samples from the total digest test were
variable with the highest concentration coming from sludge TOOK (inorganic
pigment). Mobilization of manganese in the elutriate test was generally low,
less than one percent. Sludges fixed by process C showed significant mobili-
zation of manganese. Solubilization of manganese was generally low with the
exception being fixed sludge TOOC which produced a hQ percent solubilization.
Molybdenum—
The total digest test indicated that varying amounts of molybdenum were
contained in the sludges. The highest concentration of molybdenum was found
in sludge TOOK (inorganic pigment). Molybdenum analyses were conducted on
elutriate from the fixed sludges. The results indicated little mobilization
of molybdenum in the elutriate test. The solubilization of molybdenum was
generally below five percent.
Sodium—
High sodium concentrations were indicated in all sludges by the total
digest test. Sodium compounds are used in some of the sludge generating
processes either as part of the industrial process or as a treatment step.
Sodium, as a contaminant, is found in many materials used in the processes
that generate the sludges. Sodium is also a contaminant in some of the
fixation additives.
Sodium migration along with solubilization in the elutriate test was
generally high. This was to be expected since many sodium compounds are
fairly soluble. Several fixed sludges resulted in solubilizations of over 100
percent. These high solubilization values are probably due to nonhomogeneous
samples being used in the elutriate test and the total digest test.
Nickel—
Nickel concentrations in samples from the total digest test were variable
with the highest concentrations in the raw and fixed sludges from sludge
series 200 (electroplating) and 300 (nickel/cadmium battery). Nickel migration
3T
-------
in the elutriate test was generally low except for sludge 200C. It should be
noted that even with the high concentrations of nickel associated with sludge
300, very little nickel was released in the elutriate test indicating that
nickel is fairly immobile under these conditions. Solubilization of nickel
was generally low, less than one percent, with the exception of fixed sludges
200C and 800A.
Lead—
The total digest test data indicated high lead concentrations for sludge
series 200 (electroplating) and TOO (inorganic pigment). Sludge 300R (nickel/
cadmium battery) also had a high lead concentration. Lead migration in the
elutriate test was generally low except for fixed sludges TOOC and 1000A.
Solubilization of lead was generally low, less than 0.1 percent, with fixed
sludge TOOC being the exception. Overall, the data indicated that lead was
fairly immobile in the elutriate test.
Selenium—
Selenium analyses were conducted on elutriate from raw and fixed sludges.
Selenium concentrations were variable but no sludge produced a significantly
high concentration in the elutriate. Selenium analyses were not conducted on
samples from the total digest test and therefore no comparisons could be
made.
Tin--
Tin analyses were conducted on samples from the total digest test. High
tin concentrations were indicated for raw and fixed sludges from sludge
series 200 (electroplating) and TOO (inorganic pigment).
Vanadium—
Vanadium analyses were conducted on samples from the total digest test.
Concentrations of vanadium were varible with the highest concentration being
indicated from sludge 600R (PGD, lime, western coal).
Zinc-
High zinc concentrations were indicated in the total digest test for raw
and fixed sludges in sludge series 200 (electroplating), 300 (nickel/cadmium
battery), and TOO (inorganic pigment). Zinc mobility as indicated in the
elutriate test was low except for sludges fixed by process C. Solubilization
of zinc was generally low with sludges fixed by process C resulting in the
only significant Solubilization.
COMPARISON OF FIXATION TECHNIQUES
The elutriate test was developed to provide a fast, easy method for
predicting the migration of contaminants from a sludge to the environment.
By comparing the migration of contaminants from sludges fixed by different
processes, it is possible to determine the relative success of each fixation
process. This comparison has been simplified through use of several com-
parative matrices. These matrices are presented in Tables 8-11. The metals
included in the matrices are those for which analyses were conducted on the
elutriate from both raw and fixed sludge samples. The first three matrices
illustrate metal attenuation (or containment) in each sludge by each fixation
38
-------
TABLE 8. METAL ATTENUATION BY FIXATION (0 PERCENT)
Fixation Identification
Sludge
Identification
100
200
300
Uoo
500
600
700
800
900
1000
Avg
A
^
67
33
75
25
75
N
27
33
h2
h"J
B
67
58
67
83
55
58
N
36
17
33
53
C
Nb
25
N
N
N
N
0
N
N
N
13
E
83
N
N
75
6k
83
N
N
N
33
68
F
67
N
N
N
N
73
N
N
N
N
70
G
N
N
N
N
U5
N
N
N
N
N
te
Avg
65
50
50
78
U7
72
0
32
25
36
Expressed as percent.
Sludge not fixed by processor or sample not evaluated.
39
-------
TABLE 9. METAL ATTENUATION BY FIXATION (50 PERCENT)
Fixation
Sludge
Identification
100
200
300
400
500
600
700
800
900
1000
Avg
a
Expressed as
A
33a
42
25
50
8
50
N
27
17
17
30
percent.
B
42
33
42
58
27
58
N
9
17
17
34
c
N*
17
N
N
N
N
0
N
N
N
9
Identification
E
83
N
N
67
45
83
N
N
N
25
61
F
58
N
N
N
N
64
N
N
N
N
6l
G
N
N
N
N
9
N
N
N
N
N
9
Avg
54
31
34
58
22
64
0
18
17
20
Sludge not fixed by processor or sample not evaluated.
40
-------
TABLE 10. METAL ATTENUATION BY FIXATION (90 PERCENT)
Fixation Identification
Sludge
Identification
100
200
300
Uoo
500
600
TOO
800
900
1000
Avg
A
lTa
8
IT
IT
0
50
N
0
8
8
lU
B
8
8
8
25
0
33
N
9
0
IT
12
C E
i* te
8 N
N N
N 25
N 9
N U2
0 N
N N
N N
N 8
h 25
F
U2
N
N
N
N
33
N
N
N
N
38
G
N
N
N
N
9
N
N
N
N
N
9
Avg
2T
8
13
22
5
UO
0
5
*
11
Q
Expressed as
percent.
— 4- «-3
Ul
-------
TABLE 11. ATTENUATION OF VARIOUS METALS
Fixation Identification
Metal
As
Ca
Cd
Cr
Cu
Mg
Mn
Ni
Fb
Se
Zn
A
5/9
5/9
2/9
2/9
6/9
7/9
6/9
5/9
3/9
U/9
U/8
B
6/9
8/9
3/9
1/9
U/9
9/9
7/9
5/9
3/9
6/7
6/7
c
0/1
1/2
0/2
0/2
0/2
1/2
0/2
0/2
1/2
0/2
0/2
E
3/5
5/5
V5
2/5
U/5
V5
V5
U/5
V5
3A
3/4
F
1/2
2/2
2/2
2/2
1/2
2/2
1/2
2/2
1/1
2/2
2/2
G
0/1
1/1
0/1
1/1
1/1
0/1
0/1
0/1
1/1
0/0
0/0
-------
process. The first matrix (Table 8) is based on a greater than zero percent
attenuation of a metal; the second matrix (Table 9) is based on a greater than
fifty percent attenuation of a metal; and the third matrix (Table 10) is based
on a greater than 90 percent attenuation of a metal. The number of metals
successfully contained attenuated is expressed as percent of the total number
of metals for which analyses were conducted. For example, in Table 8 (greater
than zero percent attenuation) under sludge 100 and fixation process A, the U2
indicates that out of 12 metals, the concentration of five of these was the
same or lower in the elutriate of fixed sludge 100A than in the elutriate of
sludge 100R. Achieving a 50 percent attenuation indicates that the concentration
of a metal in the elutriate of the fixed sludge sample is less than or equal
to one-half the concentration of the same metal in the elutriate of the raw
sample. Similarly, a successful 90 percent attenuation indicates that the
concentration of a metal in the elutriate of a fixed sludge sample is less
than or equal to one-tenth the concentration of the same metal in the elutriate
of the raw sample. In the case where both concentrations were below the
detection limit of the analytical equipment, no comparison was made. The
matrices can be used to compare the fixation processes on an individual sludge
basis or on an overall basis. It should be noted that each fixation processor
did not work with the same number of sludges and therefore average values may
represent work conducted on only one or two sludges.
The highest success rate in Table 8 (greater than zero percent attenua-
tion) was 83 percent for sludges 100E, UOOB, and 600E. This indicates that no
fixation process was able to limit the migration of all the metals to a level
below the concentration of the metal in the elutriate of the raw sludge. The
lowest success rate was zero percent for sludge TOOC. As indicated by the
average values, process F had the greatest overall success rate and process C
had the lowest overall success rate. In terms of average values for the
sludges, sludge UOO was the easiest sludge to fix and sludge TOO was the
hardest. In general, the data indicated that the fixation processors had
greater success in fixing the FGD sludges than in fixing the industrial
sludges.
Table 9 contains percentage values for metal attenuation at the 50
percent level. These values indicate the percent of the total number of
metals in the elutriate of a fixed sludge sample that are attenuated to a
concentration level at least one-half that of the concentration level in the
elutriate of the raw sludge. The highest success rate in Table 9 was 83
percent for sludges 100E and 500E and the lowest success rate was zero percent
for sludge TOOC. The highest average value for attenuation by a fixation
process was 6l percent for fixation processes E and F. The average values
indicate that the fixation processors had the highest success rate with sludge
600.
Table 10 contains percentage values for metal attenuation at the 90
percent level. These values indicate how successful the fixation processes
were at achieving at least 90 percent attenuation of the metals.
The highest success rate in Table 10 was 50 percent which occurred for
sludge 600A. The lowest success rate was zero percent which occurred for
sludges 500A, 800A, 500B, 900B, and TOOC. Considering average values for
-------
fixation processes, process F was most successful with a success rate of 38
percent. Sludge 600 appeared to be the best sludge for the fixation processors
with a success rate of hO percent.
The data from Tables 8-10 indicate that sludge 600 was the easiest to fix
and that excluding sludge TOO (only one fixation processor), the processors
had the lowest success rate with sludge 900. It should be noted that the
matrices consider all metals to be equal for purposes of calculating attenuation.
Obviously, certain metals present a greater hazard to the environment than do
others. This problem must be considered in any evaluation of a fixation
technique. It should also be noted that different fixers chose to work with
only certain sludges and therefore strict comparison of fixers is difficult.
Such a comparison is outside the scope of this study.
A fourth matrix (Table 11) was developed to provide information on the
success of each fixation process on various metals. This matrix is based on
a better than zero percent attenuation. For example, under fixation process
A and arsenic, the ratio 5:9 indicates that out of nine sludges fixed by
process A, the concentrations of arsenic in five of the fixed sludge elutriate
samples were less than or equal to the concentrations of arsenic in the
corresponding raw sludge elutriate samples. If the concentrations of the
metal in the two elutriate samples were both below detectable limits, then no
comparison was made. The information in Table 11 indicates that cadmium and
chromium were the most difficult metals to attenuate. The fixation processes
appeared to have the best success with the attenuation of calcium, magnesium,
and manganese.
-------
SECTION 7
INTERPRETATION OF ELUTRIATE TEST RESULTS
The data obtained from the elutriate test vas used to compare the
relative success of each fixation process in limiting the migration of
pollutants from the sludges. The success rates of the various fixation
processes were discussed in the previous section of this report. It should
be noted that most of the fixation processes were only partially successful
in limiting the migration of certain toxic metals (especially cadmium, chro-
mium, and selenium). The success rates for metal attenuation were extremely
low for the industrial wastes. Tables 8 and 11 indicate that the fixed
sludges produced higher concentrations of certain metals in the elutriate
than did the raw sludges.
A review of the fixation processes used in the study was conducted to
identify factors that could contribute to the poor success of the fixation
processes in limiting metal migration. Several problem areas associated with
the fixation processes were identified during the review. Since all of the
processes are commercial, detailed process descriptions are proprietary and
cannot be included in this report. Therefore, only a general discussion of
problems associated with certain fixation processes has been included. These
problems can generally be associated with changes in sludge permeability, pH
control, and the composition of the process additives.
The fixation processes under study reduce pollutant mobility primarily
by altering the physical properties of the sludges. These properties include
the surface area-to-volume ratio and the permeability. During the fixation
process, if the pollutants can be trapped in a mass with a very low perme-
ability, the leaching potential for the pollutants will be small. Any reac-
tion taking place between the sludge and the fixation additives during or
after the fixation procedure that would effectively increase the permeability
of the material would probably result in an increased leaching of contami-
nants. Results from studies involving the corrosion of concrete due to
sulfate ions have indicated two such reactions that could occur during or
after certain fixation processes.(lO,ll) The first reaction involves the
formation of gypsum from sulfate ions and calcium hydroxide by crystalliza-
tion with the adsorption of two molecules of crystal water.(10) This reac-
tion is accompanied by an increase in volume which can induce expansion of
the material in which the gypsum is being formed. The resulting expansion
and fracturing of the material increases the permeability.
The second reaction can occur in fixation processes where tricalcium
aluminate is available. The tricalcium aluminate reacts with gypsum to
produce a complex calcium sulfoaluminate hydrate.(10,11) This compound
-------
crystallizes with the adsorption of 31 molecules of crystal water which
results in a considerable increase in volume. This reaction is especially
detrimental during the later stages of curing. The resulting fracturing of
the fixed sludge mass will greatly increase the permeability. (The resulting
swelling of the fixed sludge mass has actually been observed in a column
leaching test).
The fracturing of any fixed sludge samples by these or other reactions
could cause an accelerated physical deterioration of the sample during the
elutriate test. The resulting increase in exposed surface area would in-
crease the pollutant migration rate to the elutriate. In a disposal site, an
increase in the permeability of the sludge mass would accelerate the migra-
tion of the pollutants to the surrounding environment.
The next major problem associated with the fixation processes is that of
pH control. The pH of the sludge-additive mixture is particularly important
in several of the fixation processes. For example, in one process, the pH
must be maintained at a fairly low value for the fixation reaction to occur.
The metals become more soluble as the pH decreases. During this fixation
process, the metals in solution are trapped in interstitial water and are
later released during the elutriate test. This can result in higher concen-
trations of certain metals being found in the elutriate of a fixed sludge.
Another problem resulting from pH control involves the increased solu-
bility of amphoteric metal hydroxides at high pH values. Many of the fixa-
tion processes use lime or lime derivatives which tend to increase the pH of
the sludge. An increase in the pH of the elutriate can result in increased
concentrations of these amphoteric metals in the elutriate.
The final problem to be discussed concerns the composition of the pro-
cess additives. The additives used in the fixation processes can contain
high levels of contaminants. An example of such an additive is fly ash.
Table 12 presents trace element compositions for several fly ash samples from
different coal-fired generating stations. As illustrated in this data, the
concentrations of certain trace elements are as high or higher than the
concentrations in the sludges being fixed. The use of this type of additive
can result in a higher concentration of certain pollutants being available
for leaching from the fixed sludges. It should be noted that these higher
available pollutant concentrations in the sludges will not necessarily result
in higher concentrations in the elutriate because of permeability and surface
area-to-volume changes resulting from fixation reactions. The effect of
different additives on the performance of a fixation process will be de-
pendent on the proportion of additives used and on other factors as discussed
above.
-------
TABLE 12. FLY ASH TRACE ELEMENT ANALYSIS(12)
Sample Number
Element
Sb
As
Ba
Be
B
Cd
Cr
F
Ge
Hg
Pb
Mn
Mo
Ni
Se
V
Zn
Cu
1
i.oa
3.2
3600
5.2
179
.39
5.6
377
1.2
.126
6.h
157-
7.0
3^.2
1.7
<50.
92.
U3.
2
1.5
7U.
700
7.5
27^
l.U
3.6
83.9
12.1
<.010
17.
2U2.
6.U
75.1
3.27
<100.
102.
113.
3
2.5
56.6
750
13.1
392
5.3
28.0
210.
25.1
.1U6
27.
273.
5.9
108.
lU.7
<25.
85^.
59.
U
u.u
6l.
15000
5-2
10UO
U.2
8.9
2880.
9-2
<.010
Ji.O
37^.
12.
92.9
16.U
<100.
386.
238.
All results are reported as the average of duplicate analyses.
are in ppm on a dry sample basis.
U7
Analyses
-------
SECTION 8
ELUTRIATE TEST AND LONG-TERM LEACHING TEST COMPARISON
BACKGROUND
The applicability of the elutriate test in comparing relative pollutant
migration from rav and/or fixed sludges has been discussed in previous sections
of this report. In order to further evaluate the applicability of the elutri-
ate test, a comparison was made between elutriate test results and long-term
leaching column results. The main objective of this comparison was to deter-
mine if the elutriate test results could be used to predict the total pollutant
migration from a sludge.
Data on total pollutant migration was obtained from analysis conducted
on leachate from a series of columns containing both raw and fixed sludges.
The leaching of the sludges was conducted over a two-year period with samples
being collected periodically. A discussion of this study can be found in an
earlier project report (5)- The analysis of the leachate samples taken late
in the study has not been completed and therefore this report includes column
leaching data for only the first 39 days of the study. This is sufficient
data to provide a trend in the comparison of the leachate test results and
the column test results.
After examining the vast amount of data available from the ten different
sludges, the decision was made to examine only one sludge in detail with
regard to a comparison between the two tests. Sludge 500 was chosen for
close examination due to the amount of analytical data available on various
metal species at the time the comparison work was done. Data for the comparison
work included results from tests on raw Sludge 500 and fixed Sludge 500A,
500B, 500E, and 500G.
CORRELATION DEVELOPMENT
The amount of pollutant migration was calculated using the volume of
leachate collected and the concentration of a particular metal in each sample
of leachate as follows:
n
W = £ VC
1=1
1*8
-------
TIME
Figure 1. Total weight of metal species leached with respect to time.
-------
.10
.09
o. .08
2
a .07
2 .06
_i
I-
§ .05
O
1.04
UJ
fe .03
.02
.01
PLOT OF Y VS X
SAMPLE SOOA-Cd
10
15
20
DAYS
25
30
35
40
Figure 2. Sample 500A - Ca linear plot
-------
v/i
H
1
.09L
PLOT OF Y VS X
SAMPLE 500A-Ca
Figure 3. Sample 500A - Ca exponential plot
-------
VJl
ro
o>
o
<
o
<
UJ
o
20
18
16
14
12
10
8
6
4
PLOT OF Y VS X
SAMPLE 500R-Pb
10
15
20
DAYS
30
35
40
Figure 4. Sample 500R - Pb
-------
u>
1.00-.
PLOT OF Y VS X
SAMPLE SOOA-Ni
o>
I
10
15
20
DAYS
25
30
35
40
Figure 5. Sample 500A - Ni
-------
1.00
.90
S.80
•k
O
£.70
O
UJ
.60
§.50
O
LU
5-30
_J
ID
1-20
.10
PLOT OF Y VS X
SAMPLE 500R-Mn
l
10
15
20
DAYS
25
30
35
40
Figure 6. Sample 500R - Mn
-------
PLOT OF Y VS X
SAMPLE 500G-Mg
D>
2'
•»
o
UJ
o
UJ
V/l
V/l
O
<
UJ
1
ID
5
O
X
I
10
15
20
DAYS
25
30
35
40
Figure 7. Sample 500G - Mg
-------
VJ1
ON
Q
UJ
O
<
UJ
UJ
1.00
.90
.80
.70
.60
.50
.40
.30
.20
O
.10
PLOT OF Y VS X
SAMPLE SOOG-Cu
1.
10
15
20
DAYS
25
30
35
40
Figure 8. Sample 500G - Cu
-------
vn
1.00
.90
..80
.70
^.60
O .50
<
LJ -40
<; .30
13 20
o • v
.10
PLOT OF Y VS X
10
SAMPLE 500G-Ca
_L
15
20
DAYS
25
30
35
40
Figure 9. Sample 500G - Ca
-------
where: ¥ = Total weight of metal species leached in the column test (mg)
V = Volume of leachate in sample (a)
C = Concentration of metal species in leachate sample (mg/Jl)
n = Total number of samples collected
It was anticipated that the total weight of a metal species leached would
asymptotically approach a limiting value if the leaching test was continued
for a sufficiently long period of time (Figure l). This limiting value would
indicate that most of the metal species available for leaching had migrated
out of the sludge.
A comparison was made for a particular sludge between the total weight
of a metal species in the column test and in the elutriate test as follows:
R - £
R ~ E
where: R = Ratio of the two weights
W = Total weight of metal species leached in the column test (mg)
E = Total weight of metal species found in the elutriate from the
elutriate test (mg)
The ratio R should have a limiting value of 1 if the elutriate test strictly
predicts the total migration of a pollutant.
CORRELATION GRAPHS
A series of graphs were developed plotting the cumulative ratio of the
weights of metal species leached from each test. Several of these graphs are
presented in this report as examples. In each graph, the data points were
used to develop a linear regression line of two types (a) a straight line and
(b) an exponential curve (Figures 2 and 3). The exponential curve should
have provided a good fit if the data points were asymptotically approaching a
constant.
The graphs indicated that the exponential curve provided a fairly good
fit for certain metals such as manganese (Figure U), nickel (Figure 5), and
lead (Figure 6). The straight line provided a good fit for most of the other
metals including calcium (Figure 7), copper (Figure 8), and magnesium (Figure
9). The graphs also indicated that in general the cumulative ratios exceeded
a value of 1.
INTERPRETATION
The difference between the-theoretical correlation and the actual corre-
lation is probable due to several factors. The first factor concerns the
solubility of the metal species in the leachate. The solubility of a metal
species limits the amount of that metal that can be transported out of the
sludge. Metal solubilities are dependent on elutriate pH and temperature,
other species in solution, and the chemical form of the particular metal
being taken into solution.
58
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In the elutriate test, if the solubility of a metal species was limiting,
the test would result in a low indication of metal available for leaching.
This phenomenon could easily occur for metals such as calcium and magnesium or
for any other metals which are found in high concentrations in the sludges. In
this case, the cumulative ratio of the weights of metals species leached from
the two tests would be greater than 1.0 since the amount of metal found in the
elutriate was limited.
In the column test, if the solubility of a metal species was limiting, a
large number of column volumes of leachate would be required to elute the
metal. This would result in a fairly constant concentration of the metal
species in the leachate resulting in a linear relationship between the cumu-
lative ratio and time. This linear relationship would deteriorate then enough
of the metal species was eluted so that solubility is no longer the limiting
factor.
Several other factors resulting from differences in testing procedures
could also have resulted in the discrepancy. One factor that must be consid-
ered is the difference in weight of the sludge samples in the two tests. The
much larger weight of sample in the column test could supply much more of a
particular metal species than the sample in the elutriate test. This factor
would result in a cumulative ratio much higher than 1.0.
Next, the samples from the elutriate test were filtered as a result of
separating the sludge from the elutriate. The samples of leachate from the
columns were not filtered which could have permitted particulate matter to
pass into the leachate samples. The samples were fixed with acid and the re-
sulting drop in pH probably solubilized any metals associated with the parti-
culate matter. This situation would result in a cumulative ratio higher than
1.0.
As mentioned previously, many of the sludge samples deteriorated during
the elutriate test due to the shaking procedure in the test. This deteriora-
tion resulted in a higher surface area-to-volume ratio for the sludges in the
elutriate test than in the column test where most of the sludges did not
deteriorate. This higher surface area-to-volume ratio could produce a higher
metal migration rate resulting in a cumulative ratio less than 1.0.
The final factor involves the analytical detection limits for the various
metals. The concentrations of some metals in the leachate samples from the
columns fell below the detectable limit after a period of leaching. Small
quantities of these metals were being leached out continuously but could not
be detected. This factor could result in an indication of a ceiling for the
cumulative ratio whereas the cumulative ratio was actually increasing in
value.
DISCUSSION OF RESULTS
The correlation study between the elutriate test data and the columns
test data indicated some problems with the elutriate test in its present form.
The solubility problem associated with the elutriate test could probably be
solved by repeating the test on the same sludge sample until the concentration
59
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of the metal species of interest is not solubility limited. The solubility
problem associated with the column test could be allevaited by continuing the
test until the metal species is sufficiently leached so that solubility is
not a limiting factor. This extended leaching test may be prohibitive in
terms of the time needed to complete the test.
The problem of difference in weights of sludge used in the two tests can
be solved by applying a correction factor to the results of the elutriate
test. This factor is the ratio of weights of the two sludges as used in each
test.
The other problems are not so easily solved and are due primarily to
basic differences in testing procedures. Modifications would be required to
both tests such as reducing the shaking action in the elutriate test, filter-
ing the leachate samples from the columns or not filtering the elutriate
samples, and changes in analytical techniques.
Although the elutriate test as described in this report has proven
useful in comparing relative pollutant migration from raw and/or fixed sludges,
several modifications of the elutriate test procedure are necessary before
the test can accurately predict total pollutant migration as indicated in the
column test study.
60
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REFERENCES
1. Keeley, J. W. and R. M. Engler- Discussion of Regulatory Criteria for
Ocean Disposal of Dredged Materials: Elutriate Test Rationale and Impli-
mentation Guidelines. Report D-T^-lU, U. S. Army Engineer Waterways
Experiment Station, Office of Dredged Material Research, Vicksburg,
Mississippi, 197^. 13 pp.
2. Environmental Protection Agency. Ocean Dumping; Criteria. Federal
Register 38 (198): 12872-12877, 1973.
3. Environmental Protection Agency. Ocean Dumping; Criteria. Federal
Register 38 (198): 28610-28621, 1973.
U. Mahloch, J. L. Progress Report on Chemical Fixation of Hazardous Waste
and Air-Pollution-Abatement Sludges. U. S. Army Waterways Experiment
Station, Vicksburg, Mississippi, 1975- ^3 pp.
5. Mahloch, J. L. , D. E. Averett , and M. J. Bartos , Jr. Pollutant Potential
of Raw and Chemically Fixed Hazardous Industrial Wastes and Flue Gas
Desulfurization Sludges - Interim Report. EPA-600/2-76-182, U. S. Environ
mental Protection Agency, Cincinnati, Ohio, 1976. 10^ pp.
6. Lee, G. F. and R. H. Plumb. Literature Review on Research Study for the
Development of Dredged Material Disposal Criteria. Report D-7^-1, U. S.
Army Engineer Waterways Experiment Station, Office of Dredged Material
Research, Vicksburg, Mississippi, 197^. 1^5 pp.
7. Chemical Laboratory Division of Dugway Proving Ground. Migration of
Hazardous Substances Through Soil. Unpublished Progress Report. Dugway,
Utah, 197^- 3A pp.
8. American Public Health Association. Standard Methods for the Examination
of Water and Wastewater, lUth Edition. Washington, D. C., 1975- 1193 pp.
9. Nebergall, W. H. , F. C. Schmidt, and H. F. Holtzclaw, Jr. College Chem-
istry, 3rd Edition. Raytheon Education Company, Boston, Massachusetts,
1968. 760 pp.
10. Biczok, I. Concrete Corrosion and Concrete Protection, 2nd Edition.
Publishing House of the Hungarian Academy of Sciences, Budapest, Hungary,
196U. 5^3 pp.
11. Lea, F. M. The Chemistry of Cement and Concrete, 2nd Edition. St. Martin's
Press Inc., New York, New York, 1956. 637 pp.
61
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REFERENCES (Continued)
12. Radian Corporation. Environmental Effects of Trace Elements from Ponded
Ash and Scrubber Sludges. NTIS Report PB-252-090, National Technical
Information Service, Springfield, Virginia, 1975. ^-02 pp.
62
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TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing/
1. REPORT NO.
EPA-6QO/2-79-154
3. RECIPIENT'S ACCESSION-NO.
4. TITLE AND SUBTITLE
ELUTRIATE TEST EVALUATION OF CHEMICALLY
STABILIZED WASTE MATERIALS
5. REPORT DATE
August 1979 (Issuing Date)
6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
Douglas W. Thompson
8. PERFORMING ORGANIZATION REPORT NO.
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Environmental Laboratory
U.S. Army Engineer Waterways Experiment Station
Vicksburg, Mississippi 39180
10. PROGRAM ELEMENT NO.
1NE624 COS SOX 1
1DC818 SOS 1 Task 27
11. CONTRACT/GRANT NO.
EPA-IAG-D4r0569
12. SPONSORING AGENCY NAME AND ADDRESS
Municipal Environmental Research Laboratory—Gin, OH
Office of Research and Development
U.S. Environmental Protection Agency
Cincinnati, OH 45268
13. TYPE OF REPORT AND PERIOD COVERED
Final August 1976-August 1977
14. SPONSORING AGENCY CODE
EPA/600/14
15. SUPPLEMENTARY NOTES
Project Officer: "Robert E. Landreth—(513) 684-7871
16. ABSTRACT
A distilled water shake test, the elutriate test, was developed and tested to provide
a fast, simple, procedure for predicting the escape of pollutants from treated and
untreated sludges. The preliminary test consisted of subjecting various treated and
untreated flue gas desulfurization (FGD) and industrial waste sludges to the elutriate
test procedure and measuring the levels of a wide variety of constituents in the
elutriate and comparing these with analyses of digested sludges. The resulting data
are presented as percent attenuation and a comparison is made between treated and
untreated wastes.
The shortterm elutriate test results were compared to results of a longterm leaching
test using the same treated and untreated sludges. The results suggest that the
elutriate test may be useful in predicting the pollutant potential of various treated
or untreated wastes. Further research and modifications are suggested to improve the
predictive value of the test.
This report is submitted in partial fulfillment of Interagency Agreement No. EPA-IAG-
D40569 between the U.S. Environmental Protection Agency, Municipal Environmental
Research Laboratory, Solid and Hazardous Waste Research Division (EPA, MERL, SHWRD)
and the U.S. Army Engineer Waterways Experiment Station (WES). Work for this report
19//.
17.
was conducted HufTng the
DESCRIPTORS
b.IDENTIFIERS/OPEN ENDED TERMS C. COSATI Field/Group
Wastes, Stabilization, Leaching, Sludge,
Permeability, Pollution, Sulfates,
Sulfites
Leachate, Solid Waste
Management
Flue Gas Cleaning
Chemical Stabilization
(Fixation)
13B
18. DISTRIBUTION STATEMENT
RELEASE TO PUBLIC
19. SECUFIITY CLASS (ThisReport)
UNCLASSIFIED
21. NO. OF PAGES
71
20. SECURITY CLASS (Thispage)
UNCLASSIFIED'
22. PRICE
EPA Form 2220-1 (9-73)
63
-JUS GOVERWtltT PHimiNG OFFICE 1979 -657-060/5384
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