United States
                     Environmental Protection
                     Agency
Air and Energy Engineering
Research Laboratory
Research Triangle Park NC 27711
                     Research and Development
EPA/600/S7-85/007 May 1985
SEPA          Project  Summary
                     Assessment of  Fluidized-Bed
                     Combustion  Solid  Wastes  for
                     Land   Disposal
                     T. W. Grimshaw, R. A. Minear, A. G. Eklund, W. M. Little,
                     H. J. Williamson, and J. E. Dunn
                      Fluidized-bed  combustion  (FBC)  is
                     an  emerging  energy technology  that
                     holds promise for both high efficiency
                     of  energy conversion  and minimiza-
                     tion of adverse  air quality impacts.  A
                     major advantage of FBC is that high-
                     sulfur coal can be burned without the
                     use of flue-gas  desulfurization equip-
                     ment to meet  air quality standards.
                     During combustion in a fluidized  bed,
                     sulfur in the coal is oxidized to sulfur
                     oxides  (SOX)  as  in  conventional
                     boilers,  but these SOX then react with
                     a  sorbent that is  injected  into the
                     fluidized bed with  the coal. During
                     steady state  conditions, the  sorbent
                     constitutes more than 95% of the bed
                     material. The sorbent, typically lime,
                     limestone, or dolomite, usually forms
                     calcium sulfate  compounds, such as
                     anhydrite, when reacting with  the
                     SOX. The solid residues that  are
                     generated in  an FBC unit are usually
                     larger in volume and  have  different
                     properties than the typical bottom ash
                     from a conventional boiler.
                      The objectives of this  investigation
                     were to obtain and analyze represent-
                     ative samples of FBC wastes, assess
                     the characteristics  of leachates
                     generated from the  wastes under
                     laboratory and  field  (landfill)  condi-
                     tions, and characterize the attenua-
                     tion of the leachates by  earth mater-
                     ials  that are  typical of disposal  set-
                     tings. An attempt was made to devel-
                     op a means of predicting the leachate
                     generation behavior  of  FBC  wastes
                     under landfill  conditions on the basis
                     of  laboratory test results by estab-
lishing a rigorous  statistical  relation-
ship between the laboratory and field
leaching results. In addition, the com-
patibility of  commonly  used landfill
liner materials with  FBC waste
leachates was assessed.
  This Project  Summary was  devel-
oped by EPA's Air and  Energy Engi-
neering Research  Laboratory, Re-
search  Triangle Park,  NC, to an-
nounce  key  findings of the  research
project that is fully documented In a
separate report of the same title (see
Project Report ordering Information at
back).

Introduction
  FBC is an emerging energy technology
that holds promise for both high efficien-
cy of energy conversion and minimization
of adverse  air quality impacts.  A major
advantage of FBC is that high-sulfur coal
can be burned without the use of flue-gas
desulfurization equipment  to  meet  air
quality standards.  During combustion in a
fluidized bed, sulfur in the coal is oxidized
to SOX as in conventional boilers,  but
these SOX then react with a sorbent that
is injected into the fluidized bed with the
coal. The sorbent,  typically  lime, lime-
stone, or dolomite, usually forms calcium
sulfate compounds,  such  as  anhydrite,
when  reacting with  the SOX. The solid
residues that are generated in an FBC unit
are usually larger in volume and have dif-
ferent properties  than the typical bottom
ash from a conventional boiler.
  Although FBC wastes can be used  as
soil conditioners or  disposed of  in  im-
poundments or at sea, it is likely that

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most wastes that will be generated in the
future will  be  landfilled.  The objective of
this  investigation  was  to  assess  the
suitability  of   FBC  wastes  for  landfill
disposal  and to  determine several char-
acteristics of the waste important to land-
fill considerations. The  procedures were
to  obtain  and  analyze  representative
samples  of FBC wastes,  determine  the
composition of the wastes,  assess  the
characteristics of  leachates  generated
from  the  wastes under laboratory  and
field (landfill) conditions, and characterize
the chemical interaction  of the leachates
with earth  materials  that are  typical of
disposal settings.
  The  investigation included both  exten-
sive laboratory studies  and large field cells
to simulate actual landfill  conditions. An
attempt was made to develop a means of
predicting  the leachate  generation  be-
havior of FBC  wastes under landfill condi-
tions  on  the  basis   of  laboratory  test
results  by  establishing  a rigorous  sta-
tistical  relationship between the laboratory
and field leaching results. In addition, the
compatibility of  commonly used  landfill
liner materials with FBC  waste leachates
was assessed.  The  laboratory  studies
were  performed  at Radian  Corporation
laboratories in  Austin, TX, and the field
investigation took place at the former EPA
mine drainage control facility, about 9 mi*
south of Morgantown, WV.

Sources of Samples
  Sources of  FBC wastes were selected
to  be  as  representative of  future FBC
waste  streams as possible while,  at the
same time, being  capable of  providing
enough sample for laboratory and field ex-
periments. The waste  source selected for
pressurized FBC  (PFBC) was  the Exxon
Miniplant at Linden, NJ.  Two atmospheric
FBC (AFBC) sources  were selected—the
EPRI/B&W unit at Alliance, OH, and the
Georgetown University boiler in Washing-
ton, DC. Both AFBC units were operating
in the recycle  mode when wastes were
collected.
  Several  types  of geological  substrate
materials (termed "disposal media") were
obtained from the vicinity of the field cells
in northern West Virginia  and  eastern
Ohio.  They were selected as  represen-
tative  of  substrate materials   at  future
disposal  sites  in the eastern U.S. and in-
cluded shale, coal mine interburden, sand-
stone,  glacial till, alluvium, and limestone.
These  samples were  used  in  the  lab-
oratory and field studies to investigate the
interaction  (contaminant attenuation  and
mobilization)  of the FBC waste  leachate
with typical substrate materials.

Overview  of  Procedures
  The  principal   component   of  the
laboratory investigation was a six-step se-
quential  batch  equilibration  protocol for
assessing the characteristics  of  leachate
after  both  generation  from  FBC wastes
and exposure to  samples of the  disposal
media (Figure 1). The  leaching  steps of
the batch equilibration protocol consisted
of initial leaching of the waste (at a liquid-
to-solid mass ratio of 10:1) with deionized
water,  secondary  leaching   of  leached
waste  with  additional  deionized water
(Step 2) for up to seven repetitions; and
secondary exposure,  sequentially for up to
seven  repetitions, of leachate to  fresh
waste  in Step 3.
  The leachate  was exposed to the dis-
posal media  to assess  the  tendency  of
contaminants  to be attenuated  by  (or
mobilized from)  the  media. Step 4 of  the
protocol assessed the initial attenuation of
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-------
leachate from Step 1 when exposed  to a
sample  of   disposal  medium.  Step  5
evaluated the ability of a disposal medium
sample to  continue  to  attenuate  fresh
leachate from  Step  1.  In Step 6, the
leachate from Step 4 was repeatedly ex-
posed to new samples of disposal medium
to evaluate the progressive attenuation of
the leachate by exposure to fresh media.
Step  5 was  repeated up to nine times and
Step  6 was repeated five times.
  Samples of the FBC waste and disposal
media were  analyzed in the laboratory for
a variety of  parameters. Physical  proper-
ties that were  determined included  grain
size distribution, specific surface area, and
particle surface characteristics. The solids
composition  was  investigated by X-ray
diffraction  to  determine  the crystalline
phases present  and by sample digestion
and  analysis to determine the chemical
composition.
  The  laboratory  studies also  included
two  sets of leaching  columns,  one set
containing  only  disposal  media,   and
another set containing layers of waste and
disposal  media.  In  addition,  the  FBC
waste samples were subjected to the Ex-
traction Procedure test for hazardousness
(toxicity category) as set forth  in regula-
tions developed pursuant to the Resource
Conservation and Recovery Act. Another
component of  the laboratory studies was
the  assessment of  the compatibility of
various  landfill liner  materials with  FBC
waste leachate.
  The main feature of the field investiga-
tion  was the design,  installation,   and
operation of several large (4 ft* diameter,
7 ft  long) cylindrical field cells. Field cells
containing   Exxon  PFBC   and  Alliance
AFBC waste were constructed and oper-
ated below  ground  surface.  These field
cells were  open  at  the land  surface to
natural precipitation and  isolated from the
subsurface environment.  The  field  cells
were intended to  simulate  actual landfill
conditions in the field as closely as  prac-
ticable.  The  cells  contained   layers  of
waste and  disposal media arranged sim-
ilarly  to  a  landfill configuration,  with an
upper  layer  of  disposal   medium  to
simulate landfill  cover  material, a layer of
waste, and a lower layer of medium to
simulate  landfill  substrate  (Figure  2).
Leachate sampling points were  included
at the base of the waste layer (upper sam-
ple point)  for collection of unattenuated
leachate and  at the base  of  the lower
layer  of  disposal medium (lower sample
point)  for  collection   of attenuated
leachate.  Excess leachate was removed
from the bottom of the field cells and not
allowed to  escape into the subsurface en-
vironment.
  The field  studies  also  included  two
large-diameter  permeameters  containing
FBC  wastes.  These permeameters  were
used  to determine the  permeability of un-
compacted waste initially after emplace-
ment  and  again  after  several months of
exposure  to  weathering  processes  and
chemical changes in the wastes.
•1 ft =  30.48 cm.
 Field Cell
                             Equipment
                            r- Shell
           Connector
             Pipes
                                   Cross-Section
                                     Schematic
                                  Drum
                   a.  Layout


Figure 2.    Field cell layout and geometry.
                                                               Cross Section through
                                                               Sampling Array-
                                                               Not to scale
                                                    Disposal
                                 4 ft Diameter  Gutter Medium—1
                                                                                            FBC Waste— 1%'ft':.
                   O  Porous Cup Samplers
                      8 in. centers along 2
                      diameters, connected
                      by manifold to vacuum
                      flask
                   D  Moisture Sensing Device
                                                                                              .Sand—'/2ft'':

                                                                                            \«	!«.!.. ..
                                                                                               Filter Cloth
         Disposal
         Medium—3 ft
                                                                                    Porous
                                                                                    Cup
                                                                                                  • Sand'
                        — 7 ft Freeboard
                         Land Surface —


                           Baffle
                         \- Baffles

                           Upper
                          - Sampling
                           Array

                         \-Baffles
                                                                     ^- Baffle

                                                                      Lower
                                                                     • Sampling
                                                                      Array
                                                 Impermeable
                                                 Membrane
                                        b. Geometry

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FBC Waste  Composition:
Mineralogy  and Major
Chemistry
  The principal  crystalline phases found in
the unleached  Exxon PFBC waste  were
anhydrite, periclase, and quartz.  The most
significant components found in  the solids
analysis were calcium (22%),  magnesium
(12%), and sulfate (23%). After leaching
in Steps 1 and 2 of the batch equilibration
protocol,  the   most  prominent  minerals
were gypsum, brucite, calcite, and quartz.
Field   cell  leaching   produced  similar
crystalline materials  and also  ettringite.
The  solids  composition  of  both  the
laboratory- and field-leached PFBC waste
showed a reduction in calcium,  sulfate,
and magnesium. The leached waste from
the laboratory protocol had 12% calcium,
20% sulfate, and  8%  magnesium.  The
field-leached   waste  contained  14%
calcium,   18%  sulfate,  and  8%  mag-
nesium. Both the crystalline and chemical
composition   data   indicated   that  the
minerals were hydrated during leaching.
  Both the unleached  and leached  (Pro-
tocol Steps 1 and 2) Alliance AFBC waste
contained quartz, calcite, portlandite, and
hematite.  The   unleached  and  leached
waste differed:  the former  had  anhydrite
and lime,  and  the  latter had gypsum and
ettringite.  The  leached waste  from the
field cells had  the  same crystalline  com-
position  as  the protocol-leached waste.
Unleached Alliance  waste had  31-35%
calcium and  10-13%  sulfate. Laboratory
leaching  resulted in a  reduction of the
calcium content to 20-21 % and  of sulfate
to 1.4%.  Field  cell leaching lowered the
calcium to 21-24%, but sulfate remained
at 11%.  These results again indicate  a
hydration  of minerals during the leaching
process.
  X-ray   diffraction   analysis   of  the
unleached Georgetown  AFBC waste re-
vealed  the presence  of  portlandite, an-
hydrite,   quartz,   calcite,   lime,   and
hematite.  Leaching in the laboratory pro-
tocol (Steps 1   and 2) resulted in the for-
mation of ettringite and gypsum and the
hydration  of lime.  Before  leaching, the
Georgetown waste  was composed of 38%
calcium and 8.5% sulfate. Laboratory pro-
tocol  leaching  reduced  the  calcium to
15-23%,   and   the  sulfate  content  was
about 7%. Field cells containing George-
town AFBC  waste were not constructed.

Physical Properties of
FBC Waste
  Scanning  electron  micrographs  were
obtained  for  each of  the  three  wastes.
both  unleached  and  leached.  The  un-
leached Exxon PFBC waste consisted of
irregularly shaped particles covered with
fine  material.  A  few spherical  particles
were  also  present.  The  leached  PFBC
waste  also consisted  mostly of  irregular
particles, but it also contained lath-shaped
crystals (probably precipitated calcite or a
hydration  product  of  calcium  sulfate,
possibly gypsum).
  The  unleached Alliance AFBC  waste
also consisted mostly of irregular particles
and  a  few spheres.  The  leached  waste
consisted  of  generally  smaller  particles
than the unleached waste, including laths
similar to  those in  the   PFBC  waste.
Unleached Georgetown AFBC waste con-
tained  two  different  groups of particle
sizes,  one from  the bed  draw and  one
from the fly ash component of the waste.
The  leached waste contained little  of the
original  fine   fraction,  but  had  small
needles adhering to the coarser grains.
  Mixed  (composite)  samples of  Exxon
PFBC, Alliance AFBC,  and Georgetown
AFBC  wastes  were  dry-sieved  to  deter-
mine  the particle size distribution  of the
as-received wastes. The mean grain sizes
of these  wastes were 195  /tm for the Ex-
xon waste, 270 /tm for the Alliance waste,
and  230 /tm for the Georgetown waste.
The  grain size distributions for the  Exxon
and  Alliance waste  were quite similar,
although the Exxon waste was consistent-
ly finer grained.  The Georgetown  waste
had a different grain size distribution than
the other two wastes: there was a  higher
percentage of material below 100 /*m.
  The  specific  gravities  of the  Exxon
PFBC, Alliance AFBC,  and Georgetown
AFBC wastes (after sample grinding) were
2.49, 2.65, and 2.42,  respectively. The ap-
parent bulk densities (after sample grind-
ing)  were 1.10, 1.29, and  1.21 g/cm3, re-
spectively. The specific surface  area  for
the ground  Exxon PFBC  waste  was 0.9
mVg.
  The  field  permeabilities  of  Alliance
AFBC  and Georgetown AFBC waste were
determined by constructing large  (4  ft
diameter  and   4  ft   long)  cylindrical
permeameters at the field  site. Permeam-
eters were  constructed  above  ground,
separate from the field cells. The waste
was emplaced in the cells without com-
paction.  The  permeability of the  waste
was  determined  initially,   at an  interim
point in  the program, and at the conclu-
sion  of  the  field studies.  The Alliance
AFBC permeameter  was  operated  about
19  months,  and  the  Georgetown  AFBC
permeameter was  in  place  for  about 13
months.  Data are  given   for the  initial
permeability and the  permeability after
comparable periods  of operation.
  The  initial permeabilities  of the  two
wastes  were quite similar:  1.1  x  10~3
cm/sec for the Alliance AFBC waste and
1.7 x   10'3 cm/sec for the Georgetown
AFBC  waste.  These initial permeabilities
are within  the  range  typical  of a sandy
loam soil. After 15.5 months of operation,
the permeability  of the  Alliance AFBC
waste  decreased  to 1.1  x 1Q-« cm/sec.
The  permeability   of   the  Georgetown
waste  decreased  to 1.7 x  10~6  cm/sec
after 13 months of  operation.  These per-
meabilities  are comparable to  a silty clay
soil.

Composition  of FBC Waste
Leachate
  The   leaching  properties of the  FBC
wastes  were evaluated  in the laboratory
sequential  batch   equilibration  protocol
(Steps  1-3),  in  laboratory leaching col-
umns,  and  in the large field cells.  The Ex-
xon PFBC and Alliance AFBC  waste were
investigated in  all three sets  of  studies;
the Georgetown AFBC  waste  was evalu-
ated in the batch  equilibration protocol.
All  three wastes were also subjected  to
the Extraction  Procedure (EP) toxicity test
set forth in regulations developed  pur-
suant to the Resource  Conservation and
Recovery Act (RCRA)  of  1976. The con-
centrations   reported   below   are  mean
values   from analysis  of aliquots  from
several  repetitions of  the protocol  steps
and sample replicates. The interpretation
included here is based on overall averages
and trends  observed  from about 65,000
individual analytical  determinations.

Exxon  PFBC Waste Leachate
  Leaching of Exxon  PFBC waste  for 7
days (Step  1) produced leachates that had
calcium and sulfate  in the highest  concen-
trations.  The  pH  of  the  leachate  was
about 12. The calcium concentration was
about 1670  mg/L, and the sulfate concen-
tration  was about 1600  mg/L. Also pres-
ent in  relatively high concentrations were
potassium (250 mg/L), sodium  (17 mg/L),
and boron  (11  mg/L).  Other significant
species were chloride (4 mg/L), strontium
(2.8  mg/L),  molybdenum  (2.5  mg/L),
magnesium  (1.4 mg/L),  and   silicon (1.3
mg/L).  Other  species  were  present  in
concentrations  less than  1 mg/L.  Com-
parison of the mass of each of the major
species leached  to  the  mass  in the bulk
solids  of the  PFBC waste showed that
chloride  was as much  as 26% leached,
boron was 20% removed, strontium about

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13%, calcium about  7%,  sodium about
5%, and sulfate about 6%.
  Repeated  leaching of the Exxon PFBC
waste in Step 2 of the protocol resulted in
constant or  decreasing concentrations  of
all species except silicon and aluminum,
which showed an increase. Repetition  of
Step 3,  where the same leachate was ex-
posed to fresh waste, resulted in increas-
ing concentrations.  Only aluminum, iron,
and silicon showed decreases. Magnesium
remained constant.
  Two small, 3-in? diameter leaching col-
umns containing layers of Exxon PFBC
waste and disposal media  were used  to
evaluate the characteristics  of  leachate
generated under laboratory  column condi-
tions. These columns contained an upper
layer of shale (to simulate natural cover
material)  and a lower  layer  of  PFBC
waste.  Leachate  was collected from the
bottom  of the columns, so the composi-
tion  of  the  leachate  reflected  the  com-
bined effect  of exposure to the layers  of
shale and PFBC waste.
  The   leachates  from  these columns
again had  calcium  and sulfate  as the
species  of highest concentration: as high
as 1000  mg/L for calcium and 3000 mg/L
for  sulfate. The  pH was again  very high
(11-12).  Potassium and chloride ranged  as
high as  3500 mg/L and 410  mg/L, respec-
tively. The  total dissolved  solids  (TDS)
reached 8500 mg/L. Boron was as high  as
25 mg/L, lithium reached  4 mg/L,  and
molybdenum was as  high  as 2.8 mg/L.
Aluminum and barium  reached  1.7  and
1.2 mg/L, respectively.
  The leaching behavior of Exxon PFBC
waste under field (landfill) conditions was
evaluated  by collecting and  analyzing
leachates from the upper sample point  of
the field cells. This  leachate reflected the
combined effects of exposure of infiltra-
ting  precipitation to  an upper  layer  of
disposal medium (to simulate landfill cover
material) and an  18-in.  layer  of  PFBC
waste.   Two  of  the six PFBC field cells
had shale in  the upper layer, and the re-
maining four cells had glacial till, alluvium,
limestone, and sandstone. The cells were
operated for about 27 months, including a
6-month period  during which they  were
covered and  not  operated.  A total of  30
leachate samplings  occurred during  this
period.
  In general, many of the  species in the
upper sample point leachates  had high
concentration in the  initial  samples, but
the concentrations  showed considerable
fluctuation.   After  the  first  month   of
*1 in. = 2.54 cm.
sampling,  the  concentrations  oscillated
much  less, and  smoother  trends were
observed.  The concentration ranges  in
leachates from  the more stable period  of
operation,  when  concentrations  were
more stable, were highest for sulfate and
TDS  (generally 1000 to  10,000  mg/L),
calcium  and  potassium  (100  to  1,000
mg/L),   and  chloride,  silicon,  sodium,
magnesium, and  potassium  (10  to 100
mg/L). The pH of the field cell leachates
was generally much lower (7-8)  than  in
the laboratory protocol or laboratory leach
column leachates. There was little cell-to-
cell variation  in the concentration  ranges
of the various species, indicating that the
upper layer of disposal medium ("natural
cover  material") did  not have  a domi-
nating influence on  the composition  of
the leachate.
  The Extraction Procedure (EP) set forth
to determine  the hazardousness of waste
(toxicity category) under the provisions  of
RCRA was performed on the  Exxon PFBC
waste. The EP extractant was analyzed
for the eight metallic ions specified by the
regulations (Ag, As, B,  Cd,  Cr,  Hg, Pb,
and Se). None of these elements had a
concentration  higher  than the limits
specified  in the RCRA regulation,  so the
PFBC  waste  would  likely be classed  as
nonhazardous in the  toxicity category.
Alliance AFBC Waste  Leachate
  Leaching of Alliance AFBC  waste in the
batch  equilibration  protocol (Step  1)
yielded  leachates with  a mean  calcium
concentration of 1340 mg/L  and  a mean
sulfate concentration of 1110 mg/L.  The
pH was  also  very  high (12.3  to 12.5).
Other species  having somewhat elevated
concentrations  were  chloride (51  mg/L),
potassium  (44  mg/L),  and  sodium (13
mg/L).   Step  1   leaching   resulted  in
removal of 63% of the  chloride, 25%  of
the strontium,  and  13%  of the molyb-
denum from  the Alliance  AFBC  solids.
Calcium  and   sulfate,  which  had  the
highest  leachate  concentrations,  were
4.5% and  8.5%  removed  by  leaching,
respectively.
  With continued leaching in repetitions
of Step  2  of  the protocol,  the  leachate
concentrations  of  the  major  species,
calcium and sulfate,  generally decreased,
although  sulfate decreased only slightly.
For the  other  species examined,  14 in-
creased in concentration and 7 decreased.
The pH remained constant. Repetitions  of
Step 3, where  the same leachate sample
was repeatedly exposed to  fresh waste
samples,  resulted in increasing concentra-
tions for  almost all  parameters, except pH
and  magnesium,  which  remained con-
stant.  Aluminum,  beryllium, and  silicon
showed a  decrease followed by  an in-
crease.
  A laboratory leaching column contain-
ing Alliance AFBC waste was constructed
and operated.  It had an  upper layer  of
sandstone  (to  simulate   landfill   cover
material) and  a  lower layer of  waste.
Calcium  and  sulfate   were  again the
predominant   species  in   the  leachate
samples, with concentrations up to 1300
and 2000  mg/L,  respectively.  Chloride
(levels up to 1200 mg/L)  and potassium
(levels up to 950 mg/L)  also had elevated
concentrations. The pH was again very
high (12).
  Five  field   cells  containing  Alliance
AFBC waste  were constructed and oper-
ated. Two  of the cells contained alluvium
in the upper  layer, and the other three
cells  contained shale,  interburden, and
limestone. The cells were operated for 21
months,  from  March  1980 to November
1981. During the period of operation, 24
samples  were  collected from the  upper
sample point and analyzed.
  Leachates from the upper sample points
for all the cells  had highest concentrations
(1000 to 10,000  mg/L) for  sulfate and
TDS.  Next  highest were  calcium and
potassium,  with concentrations generally
of  100  to  1000 mg/L.  Also  significant,
with concentrations of  10  to 100  mg/L,
were silicon,  sodium,  and  strontium.
Chloride  ranged from  10 to 100  mg/L  in
some cells  and from 100 to 1000 mg/L in
others.  The pH values  were  at or near
neutral.
  The RCRA  Extraction Procedure was
performed  on the  Alliance  AFBC waste,
and  the  extracts were  analyzed for the
eight metallic ions specified by the  RCRA
regulations. The results of these  analyses
showed that the waste is likely to be clas-
sified as  nonhazardous in the RCRA tox-
icity category.

Georgetown AFBC Waste
Leachate
  Steps 1 and 2 of the laboratory protocol
were used to determine the leaching char-
acteristics  of  the  Georgetown  AFBC
waste. The species with the highest con-
centration  in the  Step  1  leachate were
calcium and sulfate, with mean values of
1500 and 1400  mg/L, respectively.  Other
species  with  lower  but still  substantial
concentrations  were chloride (24 mg/L),
potassium  (18  mg/L), and  strontium (13
mg/L).  The  mean  pH  value was 12.5.
Comparison of the mass leached  to the
mass originally present  in  the solids for
each  species showed that  chloride and

-------
strontium  were  leached  the most, with
63%  and  52%  removed,  respectively.
Sulfate and calcium, the highest concen-
tration species,  were  leached  17%  and
5%.  About  13%  of the  lithium  was
leached  from  the  Georgetown  AFBC
waste.
  Successive repetitions of Step 2  on  the
Georgetown  AFBC   waste  resulted   in
decreasing leachate concentration  trends
for most  species.  No species showed a
consistent  increase  in  concentration with
increased  leaching,   although  barium
showed an  initial increase followed by a
decrease.  Fluoride remained  constant dur-
ing the Step 2 repetitions.
  Extraction and analysis of the George-
town AFBC waste  by RCRA  procedures
showed that the waste is nonhazardous in
the toxicity category.


Attenuation  of FBC Waste
Leachate
  The attenuation of  leachates from each
of the three FBC  wastes was evaluated
separately for each  of  the  six types  of
disposal media. Attenuation was  studied
in the laboratory and field for the Exxon
PFBC and Alliance AFBC  waste and  in
the laboratory for the Georgetown AFBC
waste.  In  general, attenuation was evalu-
ated by reference to a derived parameter
termed  "fractional attenuation" (A). For
the laboratory protocol  results, fractional
attenuation is defined as:
            AL =  C' ~
                    d
 where: AL = laboratory fractional at-
              tenuation,

         C| = initial  leachate concentra-
              tion (before exposure to
              the disposal media,  pro-
              tocol Step  1), and

         Cf = final leachate concentra-
              tion (after exposure to
              the disposal media, pro-
              tocol  Step 4).
For the field cells, fractional attenuation is
defined as:
 where:  AF = field fractional attenua-
              tion,
         Cu = concentration in leachate
              from upper sample point,
              and
         CL = concentration in leachate
              from lower sample point.

  The attenuation of  FBC waste  leachate
was found  to  be quite variable  for dif-
ferent wastes,  for  different  disposal
media, and for laboratory and  field condi-
tions (Table 1). Overall, strong  attenuation
was  observed  for  more species in the
laboratory protocol than  in the field  cells.
More parameters were found to exhibit
strong mobilization in the field cells than
in the protocol. In the laboratory protocol,
about the same number of parameters ex-
perienced strong attenuation  and strong
mobilization.
Table 1.    Comparison of the Attenuation of Leachates from Three FBC Wastes Resulting from Exposure to the Disposal Media'1
Element/
Species
Al


B


Ba


Ca


Cl


Cr


F


Fe


K


Shale

EP*
AA'
GA'
EP
AA
GA
EP
AA
GA
EP
AA
GA
EP
AA
GA
EP
AA
GA
EP
AA
GA
EP
AA
GA
EP
AA
GA
Lab1
SA
N
	 7
SA
SM
—
*
WA
WA
WA
WA
WA
	
*
WA
SA
WA
—
WA
*
EM/SM
#
WA
—
N
N
N
Field3
WM
SM
#•
WA
N
tt
WA
N
It
N
WM
It
	
—
tt
N/WA
SM
tt
	
—
#
N/WA
SM
tt
N/WA
WA
t.
Interburden
Lab
WA
WA
—
SA
WA
—
WA
WA
WA
WA
WA
WA
SM
N
WA
*
WA
—
WM
SM
SM
WA
SA
—
	
N
N
Field
tt
SM
tt
tt
SM
tt
tt
WA
tt
tt
SM
»
#
—
It
tt
SM
tt
tt
—
It
tt
SM
It
tt
WA
tt
Sandstone
Lab
*8
WA
—
SA
WA
—
#
SA
WA
WA
WA
WA
	
*
WA
WA
WA
—
WA
WM
WM
WA
WA/SA
—
	
WM
WM
Field
SM
tt
It
N
tt
It
N
tt
It
N
tt
it
—
tt
It
SM
tt
tt
	
tt
»
WA
tt
It
M
tt
tt
Glacial Till
Lab
WM
WA
—
SA
SA
—
*
WA/SA
WA
WA
WA
WA
_
N
WA
WM
WA
—
WA
WM
SM
WA
»
—
—
WA
WA
Field
SM
It
It
WA
tt
tt
N
It
It
N
tt
It
_
tt
tt
N
tt
tt
	
tt
tt
WA
tt
It
WA
#
tt
Alluvium
Lab
WM
WA
—
SA
WA/SA
—
WM
N
N
WA
WA
WA
_
N
WA
WM
WA
—
WA
SM
WM
SM
SM
—
—
N
WA
Field
SM
SM
tt
N
SM
tt
N
WM
It
N
»*10
tt
	
—
tt
WM
WA
W
	
—
tt
N
N/WM
It
WA
SA
9
Limestone
Lab
SM
WA
—
SA
SA
—
WM
WA
WA
WA
WA
WA
—
N
WA
WM
SA
—
N
SM
SM
WA
SA
—
—
SM
SM
Field
SM
SM
tt
N
SM
It
WA
WM
It
N
N
It
_
—
tt
WM
WM
tt
	
—
#
WM
SM
#
N
WA
tt

-------
Table 1. (Continued)
Element/
Species
Li EP
AA
GA
Mg EP
AA
GA
Na EP
AA
GA
Ni EP
AA
GA
Si EP
AA
GA
SO4 EP
AA
GA
Sr EP
AA
GA
TDS EP
AA
GA
Zn EP
AA
GA
Shale
Lab2 Field3
SA WA
WA SA
SA tt
SA WM/SM
SM
WA tt
	 **
WM N
WM It
	 	
WM SM
N tt
N/WA
SM WA
SM It
WA N/WM
WA WM
WA #
WA N/WM
WA WA
WA «
WA
WA
WA It
NA/WM
WM SM
It
Interburden
Lab
SA
WA/SA
WA
SA
—
WA
WM
WM
WM
SA
SA
SA
WA
SM
N
NA
WA
NA
*
WA
WA
WA
WA
WA
*
SA
-
Field
tt
SM
tt
tt
SM
tt
It
WA
tt
tt
SM
It
It
SM
It
tt
SM
It
tt
WA
It
#
—
tt
tt
SM
tt
Sandstone
Lab
SA
WA
SA
SA
—
*
SA
WM
WM
	
WA
SA
WA
SM
N
WA
WA
NA
N
N
WA/SA
WA
WA
WA
SA
WA
-
Field
WM
tt
tt
SA
tt
tt
WM
It
It
	
9
tt
WA
tt
tt
WM
tt
it
WM
tt
9
	
tt
tt
WM
»
tt
Glacial Till
Lab
SA
WA
WA/SA
SA
—
WA
SA
WM
WM
SM
SA
WM
WM
SM
SM
WA
WA
WA
WA
WA
WA
WA
WA
WA
SA
SA
—
Field
WA
It
It
SA
It
It
WM
It
tt
	
tt
It
WA
tt
tt
N
tt
tt
WA
tt
tt
	
9
9
WM
tt
tt
Alluvium
Lab
WA
SA
SA
SA
—
WA/SA
SA
N
N
SA
SA
SA
WM
SM
N
WA
WA
WA
WA
N
WA
WA
WA
WA
SA
SA
-
Field
WA/SA
SA
tt
SA
SM
It
N
WA
It
	
WM/SM
tt
WA
WA
It
N
WA
tt
WA
WA
tt
	
—
tt
SM
—
It
Limestone
Lab
WA
WA
WA
SA
—
WA
WA
SM
SM
SM
SA
WA
WM
SM
N
WA
WA
WA
N
N
N
WA
WA
WA
WA
SA
-
Field
WM
N
tt
SA
SM
tt
SM
SM
It
	
SM
tt
WA
N
tt
WM
WM
tt
SM
WA
tt
	
—
tt
SM
SM
tt
'SA = Strong Attenuation (A a 0.9)
WA = Weak Attenuation (0.2 < A < 0.9)
N = No Attenuation or Mobilization (-0.2 < A
WM = Weak Mobilization (-0.9 < A <
-0.2)
< 0.2)

















SM = Strong Mobilization (A £ -0.9).
*Lab Protocol Steps 1 and 4.

3Field Cell Upper and Lower Sample Point. Last Few Months of Operation.
•EP
'AA
'GA
J(-)
*(*)
'(It)
10**
      = Exxon PFBC.
      = Alliance AFBC.
      = Georgetown AFBC.
      = Step  7 concentration was at detection limit.
      = One value of duplicate pairs was negative and one was positive so no mean value is reported.
      = No field cell.
      _ oifferent results from duplicate field cells.
Assessment of  FBC  Waste
Leachate Quality

  An  overall  assessment  of  the  en-
vironmental "acceptability" of  the  FBC
wastes  for land disposal  was  performed
by comparing: (1) the bulk composition of
FBC  wastes with  that  of the  disposal
media;  (2)  the  quality  of  FBC waste
leachate with  similar  leachate  derived
from  the disposal media;  and (3) the con-
                                           centrations of various parameters found in
                                           FBC  waste leachate with accepted water
                                           quality reference values.  The  third  com-
                                           parison is  presented here.
                                             Opinion   concerning  "safe"  ambient
                                           concentrations as well as "safe" concen-
                                           trations in  leachates and other discharges
                                           to the environment is quite varied. Several
                                           authoritative sources  were  surveyed  to
                                           form  the basis of comparison for the  FBC
                                           waste leachates.  These  sources  include
the  Primary  and   Secondary  Drinking
Water  Regulations,  the Resource Conser-
vation  and Recovery Act Regulations, and
the Quality Criteria  for Water.
  From these sources, the most stringent
reference value was selected for purposes
of the comparisons.  In  some  instances,
the  most  stringent value  may  not  be
directly applicable  to  likely  avenues  of
FBC waste leachate discharge to the en-
vironment. The  purpose  of  drawing  a

-------
comparison  in those  instances is to em-
phasize that some of the FBC leachate
concentrations  do  not  exceed even  the
most  stringent value. For many  of  the
parameters,  the most stringent criterion
possibly is too low and could  be increased
to allow for dilution and dispersion  of
FBC leachate in the environment.

  A  comparison of the  leaching and  at-
tenuation  results  showed   that  several
parameters exceeded  the reference values
in almost all phases  of the  study (both
laboratory  and  field),  including  boron,
calcium,  chromium,  sulfate,  and  TDS
(Table 2). The reference value for pH was
exceeded in all  phases of the laboratory
investigation, and potassium, manganese,
and  nickel  generally exceeded the ref-
erence value for all phases of the field
study.  Barium,  fluoride,   iron,  molyb-
denum,  strontium,  and  titanium  were
generally below the reference values for
all  phases  of  the  investigation.   Mag-
nesium was below the reference value for
the laboratory studies. In the field studies.
only  pH  was  consistently  within  the
reference  value (besides  the parameters
mentioned above for both the laboratory
and field  studies). There  was little or no
difference  between  the  laboratory  and
field results in terms of parameters which
were  consistently above  or below the
reference  value.
  For the field  cells, there appeared to be
no  significant  difference  between  cells
containing disposal media only and  cells
containing  both  waste  and   disposal
media.
Table 2.    Summary of Parameters Which Consistently Exceeded or Were Consistently Below the Most Stringent Reference Value
                         Laboratory Investigations
                                             Field Investigations




Exxon PFBC
Genera-
tion
£'
B
Ca
Cr
pH
SO,
TDS
Zn










B1
As
Ba
Cd
Cl
Co
Cu
F
Fe
K
Mg
Mn
Mo
Pb
Se
Sr
Ti
V
Attenua-
tion
E
B
Ca
Cr
Co
Cu
Ni
K
SO,
pH
TDS







B
Ba
Cl
F
Li
Mg
Sr
Ti














Alliance AFBC
Genera-
tion
£
At
B
Ca
Cd
Cr
Cu
K
Ni
PH
SO,
TDS
V





B
Ba
Co
F
Fe
Mg
Mn
Mo
Ti
Zn








Attenua-
tion
E
B
Ca
Cd
Cr
Cu
Ni
K
SO,
V
PH
TDS






B
Ba
Cl
Co
F
Fe
Mg
Mo
Sr
Ti
Zn









Exxon
Georgetown AFBC Upper
Genera- Attenua- Sample
tion tion3 Point
E B E
Ca Al SO.
pH Cl
TDS Co
Cu
F
Fe
K
Mg
Mn
Mo
Sr
Ti
Zn




B E
Ba e
Cd Co
Cr Cr
Mg
Mn
Ni
K
S0t
V
TDS







B
Ba
F
Fe
Mo
Sr
Ti
pH










PFBC
Alliance AFBC
Lower
Sample
Point
E
Al
B
Ca
Cr
Mg
Mn
Ni
K
SO,
V
TDS






B
Ba
Cl
F
Fe
Li
Mo
Sr
Ti
PH








Upper
Sample
Point
E
B
Ca
Cl
Cr
Li
K
SO,










fi
Ba
Co
F
Mo
Sr
Ti
Zn










Lower
Sample
Point
E
Al
B
Ca
Cl
Mn
Ni
K
SO,
TDS








B
Ba
Co
F
Li
Mo
K
Sr
Ti
pH








Field
Control
Cells
E
Ca
Cr
Mg
Mn
K
SO,
V
Zn
TDS








B
Ba
Cl
F
Fe
Li
Mo
Sr
Ti
PH








'£ = Consistently exceeds the most stringent criterion or standard (approximately 50% or more).
*B = Consistently below the most stringent criterion or standard I approximately 10% or less).
3Based on only two data points.
Prediction  of  Field  Leaching
Behavior of FBC Wastes
Based  on Laboratory
Results
  One of the  goals of this  investigation
was  to  determine   the feasibility  of
developing a method  of reliably predicting
the leachate generation (and attenuation)
behavior  of FBC  wastes under landfill
disposal  conditions. The hope  was  that
the field behavior might  be  predicted on
the basis of simple and relatively inexpen-
sive laboratory tests  of the  waste. Two
empirical   but  rigorous   statistical  ap-
proaches were taken to predict the chem-
ical behavior of FBC wastes after disposal
in landfills.  Both  approaches involved the
development  of  statistical  models  from
laboratory  leaching data  to  predict field
leachate  properties.  An  extensive  sta-
tistical analysis  of leaching and  attenu-
ation data for  Exxon PFBC and Alliance
AFBC waste was performed in  the first
approach. A feasibility study for the sec-
ond approach employed  leaching data for
the PFBC waste.
  The two methods differed in the steps
used to develop the statistical  models. In
the first approach, the "direct" method, a
model was  developed directly to predict
the concentrations of a  particular species
as a function of volume of leaching solu-
tion per mass of waste leached. The con-
centrations of other species did not come
into play.  In  the second approach,  the
"indirect"  method,  a  regression  model
was first developed in which the concen-
tration  of a chemical  species was pre-
dicted in  terms of the concentrations of
itself and other chemical species  at the
preceding  batch  equilibration  protocol
leaching step  and  possibly  pH  at  the
preceding   or   current  leaching   step.
Subsequently, transformations were made
through  a  set  of mathematical steps tc
produce models which predicted concen-
tration as a function of leachate  volume
per mass of waste leached.

Direct Method
  In  the  direct   method   of  analysis,
leaching behavior  was  first  analyzed.
Models were  developed from laboratory
data to  predict field leachate concentra-
tions.  When these models  were  devel-
oped, those chemical species whose con-
centrations  were  predominantly near  oi
below  detection  limits were  excluded.
Subsequently, an  analysis was performec
to quantify the agreement  between  ob-
served  field concentration  and  corres-
ponding  values   predicted from   the

-------
laboratory models. It was found that, for
the 13 species investigeated in leachates
from  the  Exxon PFBC  waste,  the mean
agreement  between the  observed  field
values and the  laboratory-predicted field
values was  within  a  factor  of  10 in  11
cases, a factor of 5 in 8 cases, and a fac-
tor of 2 in  3 cases.  For  19 species  in-
vestigated in leachates from the Alliance
AFBC waste,  the mean agreement was
within a factor of 10 in  17 cases, a factor
of 5 in 16 cases, and a factor of 2  in 10
cases.  Thus,   laboratory   models  are
capable of predicting field  trends within
an order of magnitude in most cases. The
difference  between   the  laboratory-
predicted  and field-observed values was
statistically significant  for  most  species,
however.
  The prediction of field data involved an
extrapolation,  since   the  laboratory
volumes  of leachate per  unit  mass  of
waste leached  were much larger  than
those for the field cells. Further investiga-
tion showed,  however,  that the  differ-
ences  between   field-observed  and
laboratory-predicted  values  are  not  at-
tributable  wholly or predominantly to the
extrapolation.  Actual differences between
the behavior of the laboratory  and field
chemical systems are believed to explain a
significant part  of  the  discrepancies be-
tween observed  and predicted values.
  It was  found  that prediction  of field
fractional attenuation   (AF)  values  by
models developed  from  laboratory (AL)
values was  not possible  in  most cases.
The reasons were the scatter in the frac-
tional attenuation data and the dissimilari-
ty in  the trends  observed in  the field and
the laboratory.

Indirect Method
  For the indirect  method,  more limited
investigation  was undertaken  to assess
the  overall  feasibility  of  the  approach.
Only  leaching  (no attenuation)  data  were
used,  and only the Exxon  PFBC  waste
data  (not the data from  the two AFBC
wastes) were used. The analysis was per-
formed using  laboratory protocol Steps 1
and  2 data  and  upper  sample   point
leachate  data  from  the PFBC  field cell
containing shale in  the upper layer.
  The principal finding of the modeling by
the indirect  method was that the species
fell into two  groups. In the first group,
consisting of  sulfate, silicon, chromium,
barium, sodium,  iron, calcium, zinc, and
strontium,   the  species  were   self-
controlled; that is, the concentration (at a
given  extraction  step)  of  one  of  these
species was related to concentrations (in
the preceding step) of species within the
group. Sulfate and silicon were individual-
ly self-controlled. Concentrations for the
second  group (magnesium, boron, fluor-
ide, chloride, and aluminum) were largely
controlled by the first group. That pH did
not  play  a  crucial  role  as a  predictor
variable is not surprising, since pH varied
between only 11.0 and 12.0 during the se-
quence  of laboratory extractions for the
Exxon PFBC waste.
  For  predicting field  observed  values
from  the  laboratory, the indirect method
was close for barium and  strontium and
nearly as  close  for zinc. Sulfate  was
predicted  within  a  factor  of  two, and
calcium and  chromium were  predicted
within  a  factor of  three.  Except  for
sulfate,  silicon, and sodium, the  predicted
values were higher  than  the  observed
values.

Compatibility of Landfill Liners
with FBC Waste  Leachate
  If some future FBC wastes are disposed
of in  secure landfills with liners,  the com-
patibility of commonly  used landfill liner
materials with FBC waste leachate was in-
vestigated. Under certain conditions (e.g.,
in shallow water table conditions or where
ground water is used as a nearby drinking
water  source)  even  nonhazardous  FBC
waste landfills may  utilize liners.
  The objective of  the liner investigation
was to  determine  if the liner integrity  is
reduced as  a result of exposure to FBC
waste leachate by using several chemical
and   physical  tests.  Six  synthetic  liner
materials and one clay were tested:  Neo-
prene,  polyvinyl  chloride  (PVC),  chlori-
nated   polyethylene   (CPE),   chlorosul-
fonated-polyethylene (Hypalon), butyl rub-
ber,  ethylene propylene diene  monomer
(EPDM)  rubber,  and  sodium   bentonite
clay.
  Leachate from protocol Step 1 leaching
of the Exxon PFBC waste was used in the
experiment.  For  the  synthetic  liners,
uniformly  sized strips of the liner material
were  attached to a  rack and immersed  in
a tank containing the  leachate.  The ben-
tonite clay  was suspended  in  with the
leachate,  and  the   mixture  was  con-
tinuously  agitated.   Degradation  of  the
synthetic  liner materials with  time was
monitored  by  removing samples  of the
liner strips monthly and testing  them for
tensile strength. The  leachate  was also
sampled monthly and analyzed for  total
organic carbon (TOO concentration to in-
dicate the  release  of liner  carbon consti-
tuents to the  leachate.  In addition, the
liner surfaces were examined by scanning
electron   microscope  for   direct  visual
evidence of liner degradation.
  For the clay  liner  material, degradation
was monitored  by monthly  sampling and
analysis of the clay by X-ray diffraction to
detect clay mineral breakdown. Also, the
leachate was analyzed for aluminum as a
means of  detecting  the release  of clay
mineral components  to the leachate solu-
tion. The investigation of both the syn-
thetic liner and the clay liner  continued for
18 months.
  For the  synthetic  liners,  Hypalon was
the  strongest  overall.  Four of  the six
(EPDM  rubber,  butyl rubber,  Neoprene,
and  CPE) had  very  similar  strengths,  all
lower than Hypalon's. PVC had  a strength
intermediate  between  Hypalon and  the
other four. All liners showed a decrease in
strength with increasing time of exposure
to the leachate. In terms of  percentage of
the maximum tensile strength  observed,
the  greatest drop in strength was  ob-
served for CPE, with a  decrease  to  50%
of  maximum.  The   least  decrease  in
strength  was seen for the  Hypalon and
EPDM   rubber  liners   (to  70%   of
maximum).
  Under  SEM magnification, only two of
the six liners showed evidence of signifi-
cant deterioration resulting from exposure
to the  Exxon PFBC waste leachate. Most
of the  liners could not be easily observed
because of the  formation of a  precipitate
on their surfaces. The TOC  concentration
trends showed the greatest gain in carbon
content in the leachates containing  the
Hypalon  and CPE  liners. EPDM  rubber
and  Neoprene  showed  the  lowest in-
creases   in  TOC  content   in   these
leachates.
  In general, the liner showing the least
compatibility with the Exxon PFBC  waste
was CPE, which showed the clearest sign
of chemical degradation under SEM ob-
servation  and  by  the TOC analysis.  Its
tensile strength was  in the  group of four
liners  having  the lowest  strength.  Hy-
palon,  on the other  hand,  showed signs
of chemical degradation  in  the SEM and
TOC studies, but its strength (which was
initially high) remained the  highest  of all
the liners for the duration  of the experi-
ment.
  X-ray diffraction analysis  of the  ben-
tonite  clay  that was suspended in  the
PFBC waste leachate revealed that one of
the first changes to  occur was a change
in the  clay from 'a sodium-  to a calcium-
montmorillonite  as  the  calcium in  the
leachate  replaced the sodium ions in the
surface positions of  the montmorillonite.
Although  one of the peaks on the XRD

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patterns changed slightly as  the  experi-
ment  progressed, which may have been
an  indication of incipient  breakdown  of
the aluminosilicate  structure  of the clay,
the patterns in ^general showed no major
structural change in  the  clay. -After  the
first month, a new mineral, ettringite, was
identified in the XRD pattern, which in-
dicated  a  possible change  in the basic
structure of  some  of  the  initial  clay
material.
  Throughout  the  experiment, the con-
centration  of aluminum in the leachate
was at or below the levels found in  the
leachate prior to interaction with the clay.
Thus, the  aluminum  concentration data
did not substantiate  breakdown  of  the
aluminosilicate structure of the clay over
the 18 months of the test.
  In general,  the  liner materials  tested
were found  to  be  quite compatible with
Exxon  PFBC waste  leachate insofar  as
could  be determined in this relatively short
and  simple  investigation.  If there had
been strong incompatibility of the liners
with the leachate,  then the  degradation
would have  been readily detected  in this
program. Although no strong incompati-
bility was observed, some of the polymer
liners did show a significant loss of tensile
strength during the 18 months of leachate
exposure. The formation of a new mineral
phase, ettringite, as a possible reaction
product  of the montmorillonite and  the
high-calcium leachate, could  also lead to
eventual breakdown  of the effectiveness
of the clay or a liner material.

Conclusions
  Overall,  this  investigation  shows that,
with proper consideration of  waste- and
site-specific  factors  and  with   good
engineering  practice,  the   disposal   of
wastes should not  be an  inhibitive factor
in the development and use  of the FBC
energy  conversion  technology.  The
wastes  do  not contain  (or release  to
leachate) large concentrations of highly
toxic  species  or other species that  are
hazardous to  human health  or the  en-
vironment.  There is  some potential con-
cern for certain species, such as calcium
and sulfate, which will need to  be  ad-
dressed  at future disposal sites, but prop-
er design and operation should allay these
concerns.  It appears feasible  to use readi-
ly available liner materials when necessary
in the design of FBC landfills.
T. W. Grimshaw, R. A. Minear, A. G. Eklund. W. M. Little, H. J. Williamson. T. S.
  Gibson, D, L Heinrich, and R. C. South are with Radian Corporation, Austin, TX
  78766; J. E. Dunn is with the University of Arkansas, Fayetteville, AR 72701.
John O. Milliken is the EPA Project Officer (see below).
The complete report consists of eight volumes, entitled "Assessment ofFluidized-
  Bed Combustion Solid Wastes for Land Disposal:" (Set Order No. PB 85-175
  859/AS; Cost: $130.50)
  "Volume 1. Final Report," (Order No. PB 85-175 867'/AS; Cost: $22.00)
  "Volume 2. Appendices A thru C, "(Order No. PB 85-175 875/AS; Cost: $ 16.00)
  "Volumes. Appendices D andE, "(Order No. PB 85-175 883/AS; Cost: $28.00)
  "Volume 4. Appendix F," (Order No. PB 85-175891 /AS; Cost: $ 13.00)
  "Volume 5. Appendix G," (Order No. PB 85-175 909/AS; Cost: $22.00)
  "Volume 6. Appendix H," (Order No. PB 85-175 917/AS; Cost: $13.00)
  "Volume 7. Appendix I," (Order No. PB 85-175 925/AS; Cost: $14.50)
  "Volume 8. Appendix J," (Order No. PB 85-175 933/AS; Cost: $25.00)
The above reports will be available only from: (costs subject to change)
        National Technical Information Service
        5285 Port Royal Road
        Springfield, VA 22161
         Telephone: 703-487-4650
The EPA Project Officer can be contacted at:
        Air and Energy Engineering Research Laboratory
         U.S.  Environmental Protection Agency
        Research Triangle  Park, NC 27711
                                    W
                                                                      U. S. GOVERNMENT PRINTING OFFICE: 1985/559 111/10832

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