Technical
Background
Document:
Mercury
Wastes
Evaluation
of
Treatment
of
Mercury
Surrogate
Waste
Final
Report
February
8,
2002
Submitted
to:

U.
S.
Environmental
Protection
Agency
Ariel
Rios
Building
Office
of
Solid
Waste
1200
Pennsylvania
Avenue,
N.
W.
Washington,
D.
C.
20460
Submitted
by:

Science
Applications
International
Corporation
Engineering
and
Environmental
Management
Group
11251
Roger
Bacon
Drive
Reston,
Virginia
20190
EPA
Contract
No.
68­
W­
98­
025
Work
Assignment
No.
3­
8
SAIC
Project
No.
06­
0758­
08­
1373­
000
Evaluation
of
Treatment
of
Mercury
Surrogate
Waste
Executive
Summary
The
Environmental
Protection
Agency
(
EPA)
and
Department
of
Energy
(
DOE)
have
collaborated
on
a
series
of
studies
to
evaluate
the
effectiveness
of
treatment
technologies
at
stabilizing
wastes
containing
large
concentrations
of
mercury.
The
study
described
in
this
report
was
designed
to
provide
data
to
EPA
on
stabilization
of
high­
mercury
subcategory
waste
sludges
(
wastes
containing
greater
than
260
mg/
kg
total
mercury)
that
contain
multiple
forms
of
mercury.
The
data
gathered
from
this
treatment
demonstration
should
then
provide
EPA
with
information
to
support
a
potential
revision
of
current
regulations
to
allow
a
stabilization
alternative
of
all
high­
mercury
subcategory
wastes.

The
study
evaluated
the
effectiveness
of
four
technologies
at
stabilization
of
mercury
in
a
`
difficult­
to­
treat'
mercury­
containing
waste,
representative
of
the
wide
range
of
such
wastes
that
would
require
treatment.
A
surrogate
waste
was
designed
for
the
study,
which
included
an
organic
form
of
mercury,
elemental
mercury,
and
several
mercury
salts
in
an
inorganic
matrix.
The
surrogate
waste
was
treated
by
each
vendor,
and
the
treated
waste
forms
evaluated
for
mercury
leachability,
using
both
the
TCLP
and
a
novel,
automated,
constant­
pH
leaching
protocol.
Constant
pH
leaching
was
conducted
at
pH
2,
4,6,
8,
10,
and
12
for
14
days
at
each
pH.

The
report
provides
descriptions
of
the
study
plan
and
the
treatment
processes,
as
well
as
detailed
discussions
of
the
leaching
results.
The
leaching
data
presented
demonstrate
that
the
stability
of
the
mercury
in
the
treated
waste
forms
varies
widely
across
the
pH
range
tested.
Clearly,
the
stability
of
mercury
in
these
treated
waste
forms
will
be
highly
dependant
on
the
disposal
conditions.
The
combination
of
site­
specific
disposal
conditions
and
appropriate
treatment
technology
must
be
considered
as
decisions
are
made
about
disposal
of
waste
mercury.

Project
Team
Mary
Cunningham
 
Project
Manager
EPA
1201
Pennsylvania
Ave.,
NW
Washington,
DC
20460
John
Austin
EPA
1201
Pennsylvania
Ave.,
NW
Washington,
DC
20460
Mike
Morris
ORNL­
UT­
Battelle
PO
Box
2008
Oak
Ridge,
TN
37831­
6180
Greg
Hulet
INEEL­
Bechtel
PO
Box
1625
Idaho
Falls,
ID
83415­
3875
1.
Introduction
The
Hazardous
and
Solid
Waste
Amendments
(
HSWA)
to
the
Resource
Conservation
and
Recovery
Act
(
RCRA)
require
the
EPA
to
establish
treatment
standards
for
all
listed
and
characteristic
hazardous
wastes
destined
for
land
disposal.
After
the
effective
date
of
a
restriction,
wastes
that
do
not
meet
the
Land
Disposal
Restrictions
(
LDR)
treatment
standards
are
prohibited
from
land
disposal.

The
LDR
treatment
standards
for
the
six
waste
codes
(
D009,
K071,
K106,
P065,
P091,
and
U151)
which
contain
mercury
as
the
primary
hazardous
constituent
(
Mercury
Wastes)
were
promulgated
in
the
Third
Third
LDR
Rule
(
55
FR
22520,
June
1,
1990).
Some
of
these
standards
were
revised
when
EPA
promulgated
Universal
Treatment
Standards
in
the
Phase
II
LDR
Rule
(
59
FR
47980,
September
19,
1994).
Since
these
rules
were
promulgated,
however,
the
Agency
has
become
aware
of
information
and
data
which
indicate
that
the
treatment
standards
for
some
categories
of
these
wastes
may
be
inappropriate
and
warrant
further
review.

1.1
Disposal
Options
for
Wastes
Containing
>
260
mg/
kg
Total
Mercury
Under
the
existing
LDRs,
treatment
by
stabilization
and
disposal
is
not
an
available
option
for
most
wastes
containing
greater
than
260
mg/
kg
total
mercury
(
high
mercury
wastes).
The
reasons
given
in
the
3rd
3rd
rule
for
this
regulation
are
that,
"
EPA's
data
for
untreated
mercury
wastes
being
retorted/
roasted
domestically
show
minimum
concentrations
of
mercury
up
to
255
mg/
kg,"
and
that
"
There
is
a
strong
preference
in
the
land
disposal
restrictions
legislation
for
treatment
standards
to
be
based
on
recovery
where
possible."
The
technical
background
document
for
mercury
wastes
also
cited
data
from
attempts
to
treat
K106
sludge
containing
25.9
g/
kg
of
total
mercury
using
conventional
metal­
stabilizing
agents
(
cement,
kiln
dust,
lime/
fly
ash),
indicating
that
the
leachability
of
the
waste
was
actually
increased
by
the
process.

In
light
of
EPA's
current
recognition
of
mercury
as
a
high
priority
pollutant
and
efforts
to
reduce
mercury
consumption
wherever
possible
and
take
mercury
out
of
circulation
to
minimize
air
emissions,
it
appears
that
the
general
preference
for
recovery
over
immobilization
may
not
be
appropriate
for
some
categories
of
mercury
wastes.
In
addition,
various
commenters
and
petitioners
have
submitted
data
indicating
that
wastes
containing
concentrations
well
above
260
mg/
kg
may
be
effectively
stabilized.
Therefore,
EPA
decided
to
revisit
the
issue
of
mercury
stabilization
by
gathering
performance
data
on
waste
forms
produced
by
commercially
available
treatment
technologies.

1.2
Wastes
Which
Are
Not
Directly
Amenable
to
Roasting
and
Retorting.
Retorting
or
roasting
for
recovery
(
RMERC)
is
currently
required
for
inorganic
high
mercury
wastes.
Commenters
and
petitioners
have
asserted
that
many
subcategories
of
mercury
wastes
(
e.
g.,
inorganic
salts,
corrosive
wastes,
incineration
residues,
wastewater
treatment
residues)
are
not
directly
amenable
to
RMERC
treatment,
and
are
not
accepted
by
commercial
retorting
facilities.
Although
EPA's
general
position
has
been
that
those
nonamenable
subcategories
can
be
pretreated
to
make
recovery
possible,
current
management
practices
indicate
that
this
position
may
be
impractical
and
unrealistic.
Therefore,
EPA
decided
to
investigate
alternative
treatment
technologies
to
roasting
and
retorting
for
high­
mercury
wastes.

1.3
Incineration
of
Mercury
Wastes
Incineration
(
IMERC)
is
currently
either
required
or
allowed
as
an
alternative
to
RMERC
for
organic
high
mercury
wastes.
The
rationale
for
this
standard
given
in
the
3rd
3rd
rule
is
that
IMERC
will
destroy
the
organic
component
of
organo­
mercury
complexes
or
mixtures,
so
that
the
"
valuable
mercury"
present
in
the
waste
can
be
subsequently
recovered
from
the
incineration
residuals
(
e.
g.,
ash,
baghouse
dust,
sludge
from
treated
scrubber
water).
However,
given
the
high
volatility
of
mercury,
it
is
reasonable
to
assume
that
both
mercury
and
organo­
mercury
compounds
will
be
vaporized
by
incineration
rather
than
remaining
in
the
ash.
Although
some
of
this
mercury
will
be
captured
by
air
pollution
controls,
the
rest
will
be
lost
to
the
atmosphere.
Furthermore,
evaluation
of
current
waste
management
practices
indicates
that
incineration
residuals
are
in
fact
not
being
treated
for
mercury
recovery.
Therefore,
the
Agency
has
decided
to
further
investigate
whether
treatment
alternatives
exist
for
mercury
wastes
that
might
currently
be
going
to
incinerators
for
treatment.

The
Surrogate
Waste
Project
Report
The
purpose
of
this
report
is
to
provide
data
to
EPA
on
stabilization
of
high­
mercury
subcategory
waste
sludges,
that
contain
multiple
forms
of
mercury.
The
data
gathered
from
the
demonstration
of
treatment
of
this
sludge
should
then
provide
EPA
with
information
to
support
a
potential
revision
of
current
regulations
to
allow
a
stabilization
alternative
of
all
high­
mercury
subcategory
wastes.
1
40
CFR
268.40
2
This
procedure
is
described
in
Method
1311
of
U.
S.
Environmental
Protection
Agency
(
EPA)
Publication
SW­
846.
2.
Background
The
Resource
Conservation
and
Recovery
Act
(
RCRA)
1
defines
several
categories
of
mercury
wastes,
each
of
which
has
a
defined
technology
or
concentration­
based
treatment
standard,
or
universal
treatment
standard
(
UTS).
RCRA
defines
mercury
hazardous
wastes
as
any
waste
that
has
a
TCLP
value
for
mercury
of
0.2
mg/
L
or
greater.
Three
of
these
categories,
all
nonwastewaters,
fall
within
the
scope
of
this
report
on
new
technologies
to
treat
mercury­
contaminated
wastes:

­
Wastes
as
elemental
mercury
­
Hazardous
wastes
with
less
than
260
mg/
kg
[
parts
per
million
(
ppm)]
mercury
­
Hazardous
wastes
with
260
ppm
or
more
of
mercury
2.1
Current
Treatment
Methods
While
this
report
deals
specifically
with
the
last
category
 
hazardous
wastes
with
260
ppm
or
more
of
mercury
 
the
other
two
categories
will
be
discussed
briefly
so
that
the
full
range
of
mercury
treatment
challenges
can
be
understood.
The
treatment
methods
for
these
three
categories
are
as
follows:

­
Waste
as
elemental
mercury
 
RCRA
identifies
amalgamation
(
AMLGM)
as
the
treatment
standard
for
elemental
mercury
contaminated
with
radioactive
materials.

­
Waste
with
<
260
ppm
mercury
 
No
specific
treatment
method
is
specified
for
hazardous
wastes
containing
<
260
ppm.
However,
RCRA
regulations
require
that
such
wastes
that
exceed
a
TCLP
mercury
concentration
of
0.20
mg/
L
be
treated
by
a
suitable
method
to
meet
the
toxicity
characteristic
leaching
procedure
(
TCLP)
2
limit
for
mercury
of
0.20
mg/
L.

­
Waste
with
>
260
ppm
mercury
 
For
hazardous
wastes
with
mercury
contaminant
concentrations
>
260
ppm
and
RCRA­
regulated
organic
contaminants
(
other
than
incinerator
residues),
incineration
or
retorting
(
IMERC
or
RMERC)
is
the
treatment
standard.
For
wastes
with
mercury
contaminant
concentrations
>
260
ppm
that
are
inorganic,
including
incinerator
and
retort
residues,
RMERC
is
the
treatment
standard.

Hazardous
waste
contaminated
with
>
260
ppm
mercury
is
the
primary
focus
of
this
report.
EPA's
hazardous
waste
classification
system
identifies
six
categories
of
mercury­
bearing
wastes,
each
of
which
has
a
separate
RCRA
waste
code.
Table
2­
1
shows
the
six
mercury
waste
codes
and
a
brief
description
adapted
from
the
May
28,
1999
proposed
rule:

Table
2­
1
RCRA
Waste
Codes
for
Wastes
that
Contain
Mercury
Waste
Code
Description
D009
 
Characteristic
Mercury
Wastes
D009
wastes
are
extremely
variable
in
composition,
and
depend
on
the
industry
and
process
that
generate
the
waste.
Some
of
the
more
common
types
of
D009
wastes
include
miscellaneous
wastes
from
chlor­
alkali
production
facilities
(
especially
cell
room
trench
sludge
and
activated
carbon
for
liquid
or
gas
purification),
used
fluorescent
lamps,
batteries,
switches,
and
thermometers.
D009
wastes
are
also
generated
in
the
production
of
organomercury
compounds
for
fungicide/
bactericide
and
pharmaceutical
uses,
and
during
organic
chemicals
manufacturing
where
mercuric
chloride
catalyst
is
used.

K071
 
Brine
purification
muds
from
the
mercury
cell
process
in
chlorine
production,
where
separately
prepurified
brine
is
not
used
K071
wastes
are
generated
by
the
chlor­
alkali
industry
in
the
mercury
cell
process.
In
this
process,
sodium
chloride
is
dissolved
to
form
a
saturated
brine
solution.
The
brine
solution
is
purified
by
precipitation,
using
hydroxides,
carbonates,
or
sulfates.
The
precipitate
is
dewatered
to
form
K071
wastes,
while
the
purified
brine
continues
in
the
process.
The
depleted
solution
from
the
mercury
cell
is
ultimately
recycled
to
the
initial
step
of
the
process.

K106
 
Wastewater
treatment
sludge
from
the
mercury
cell
process
in
chlorine
production
Like
K071
wastes,
K106
wastes
are
generated
from
chlorine
production
using
the
mercury
cell
process.
Effluent
from
the
mercury
cell
includes
spent
brine,
a
portion
of
which
is
recycled
and
a
portion
of
which
is
purged
to
wastewater
treatment.
Other
plant
area
wastewaters
(
e.
g.,
stormwater,
washdown
waters)
are
also
typically
sent
to
this
treatment
system.
The
wastewater
treatment
process
generates
a
sludge
through
precipitation
and
filtering,
which
is
K106
waste.
The
mercury
concentration
in
K106
waste
is
consistently
greater
than
260
mg/
kg
and
therefore
retorting
is
a
required
technology
for
this
waste.

P065
 
Mercury
fulminate
P065
wastes
consist
of
discarded
mercury
fulminate
product,
off­
specification
mercury
fulminate
product,
and
container
or
spill
residues
thereof.

P092
 
Phenylmercury
acetate
P092
wastes
consist
of
discarded
phenylmercury
acetate
product,
off­
specification
phenylmercury
acetate
product,
and
container
or
spill
residues
thereof.

U151
 
Mercury
U151
wastes
consist
of
discarded
elemental
mercury
product,
off­
specification
metallic
mercury
product,
and
container
or
spill
residues
thereof.
The
principal
constituent
of
U151
is
metallic
mercury.

*
U.
S.
EPA,
Best
Demonstrated
Available
Technology
(
BDAT)
Background
Document
for
Mercury
Wastes,
Nov
1989,
page
2
 
18.
**
Mercury
Treatment
and
Storage
Options
Summary
Report,
A.
T.
Kearney
report
for
USEPA
Reg
5,
May
1997,
page
1.

2.2
Mixed
Waste
(
RCRA
and
Atomic
Energy
Act
(
AEA))

Mixed
waste
is
waste
that
contains
both
hazardous
chemical
components,
subject
to
the
requirements
of
RCRA,
and
radioactive
components,
subject
to
the
requirements
of
the
Atomic
Energy
Act.
Mercury­
contaminated
low­
level
radioactive
waste
(
LLW)
is
considered
mixed
waste
and
is
therefore
regulated
by
both
EPA
and
the
U.
S.
Nuclear
Regulatory
Commission
(
NRC).
Given
the
combined
restrictions
of
both
EPA
and
NRC,
there
is
no
disposal
path
available
for
mixed
waste.
Since
the
radioactive
characteristic
cannot
be
eliminated,
mixed
wastes
must
be
treated
to
eliminate
the
hazardous
characteristic
so
that
they
may
then
be
disposed
of
in
accordance
with
NRC
regulations.

Treatment
requirements
for
radioactive
mercury­
contaminated
LLW
(
D009
as
designated
by
EPA)
are
governed
by
40
CFR
268.40.
Inorganic
waste
containing
<
260
ppm
non­
elemental
mercury
must
be
treated
by
RMERC,
and
the
recovered
mercury
must
be
amalgamated.
The
residues
may
be
disposed
of
as
LLW
if
they
meet
the
TCLP
test
limit
for
mercury
(
0.20
mg/
L),
provided
that
the
original
waste
did
not
have
another
RCRA
constituent
in
addition
to
mercury.
If
other
RCRA
constituents
were
also
originally
present
in
the
waste
above
TCLP
limits,
the
waste
must
be
treated
to
meet
the
UTS
for
those
constituents,
according
to
40
CFR
268.48.
In
the
event
that
the
residue
does
not
meet
the
TCLP
limit,
it
must
either
be
treated
again
by
RMERC
(
if
the
residue
contains
<
260
ppm
mercury)
to
meet
the
TCLP
limit
or
otherwise
treated
to
meet
the
UTS
(
if
the
residue
contains
<
260
ppm
mercury).

Wastes
that
originally
contained
<
260
ppm
mercury
must
be
treated
to
meet
the
UTS
(
0.025
mg/
L
for
mercury)
for
all
RCRA
constituents,
unless
RMERC
is
used,
in
which
case
the
residue
must
meet
the
TCLP
limit
of
0.20
mg/
L
for
mercury.
After
treatment
to
0.2
mg/
L
(
RMERC
residues
where
mercury
is
only
RCRA
constituent)
or
the
UTS
(
all
other
situations),
the
waste
may
be
disposed
of
as
LLW.

Elemental
mercury
must
be
treated
by
amalgamation,
after
which
it
may
be
disposed
of
as
LLW.
This
applies
to
original
and
secondary
elemental
waste
streams.

2.3
What
is
the
Impetus
for
the
Current
Study?

2.3.1
Land
Disposal
Restrictions
The
Land
Disposal
Restrictions
(
LDR)
treatment
standards
established
by
the
3rd
3rd
Rule
(
55
FR
2250,
June
1,
1990)
allows
incineration
(
IMERC)
as
a
treatment
option
for
organic
high­
mercury
wastes.
The
rationale
for
this
LDR
Best
Demonstrated
Available
Technology
(
BDAT)
treatment
standard
was
that
incineration
most
completely
destroys
the
organic
component
in
the
waste,
allowing
recovery
of
mercury
in
the
incineration
residuals.
While
incineration
destroys
the
organic
component
of
organomercury
complexes,
it
also
generates
mercury
that
enters
other
waste
or
emissions
streams.
Since
EPA
recognizes
mercury
as
a
high
priority
pollutant,
it
may
be
preferable
to
immobilize
mercury
rather
than
recover
it.
Moreover,
the
EPA
has
found
that
most
incineration
residuals
are
not
treated
for
mercury
recovery.

If
a
high
mercury
subcategory
waste
does
not
contain
organics
or
is
an
incinerator
or
retort
residue,
the
waste
is
subject
to
the
RMERC
treatment
standard.
Thus,
RMERC
must
be
used
to
treat
high
mercury
subcategory
wastes
unless
the
waste
contains
organics
and
can
be
incinerated.
In
the
3rd
3rd
Final
Rule,
EPA
cited
Congress'
preference
for
"
treatment
standards
to
be
based
on
recovery,
where
possible"
(
S.
Rpt.
98­
284,
p.
17).
In
addition,
the
Agency
cited
technical
reasons
for
not
promulgating
stabilization
as
the
preferred
treatment
technology
for
high
mercury
subcategory
wastes.
Specifically,
data
available
to
support
the
3rd
3rd
Final
Rule
indicated
that
the
metal
stabilization
agents
actually
increased
the
mobility
of
mercury
in
the
stabilized
matrix.

2.3.2
Mixed
Wastes
The
Department
of
Energy
has
analyzed
the
use
of
the
current
treatment
requirement
on
radioactive
mixed
wastes.
In
1997,
TMFA
(
then
known
as
the
Mixed
Waste
Focus
Area,
or
MWFA)
examined
the
status
of
technologies
available
to
treat
mercury­
contaminated
mixed
wastes
and
reported
technology
shortfalls
in
a
series
of
technology
development
requirement
documents
(
TDRDs)
for
amalgamation,
wastes
with
<
260
ppm
mercury,
and
wastes
with
>
260
ppm
mercury.
Technology
needs
were
found
to
exist
for
mercury
stabilization,
separation/
removal,
and
amalgamation.
The
specific
technology
needs
established
for
mercury
and
mercury­
containing
waste
were
(
1)
verification
of
mercury
stabilization
technology,
(
2)
development
of
new
technology
for
chemically
or
physically
removing
mercury
contamination
for
separate
stabilization,
and
(
3)
development
of
methods
and
equipment
designs
for
amalgamating
bulk
nonrecyclable
mercury.
These
three
goals
are
summarized
in
following
table.

Table
2­
2
Prioritized
List
of
Technology
Needs
for
Mercury
and
Mercury­
contaminated
Wastes
Technology
Need
Description
1.
Mercury
Stabilization
Toxic
metal
contaminants
(
regulated
under
RCRA)
contained
in
mixed
wastes
require
removal
or
stabilization
to
control
solubility
under
TCLP
conditions
before
disposal
of
the
wastes
is
allowed.
Under
RCRA
regulations,
waste
at
contamination
levels
of
<
260
ppm
mercury
(>
260
ppm
requires
retorting)
requires
stabilization
to
control
mercury
solubility
to
<
0.2
ppm.
a
Verification
of
treatment
(
penetrating
the
entire
matrix
and
stabilizing
essentially
all
of
the
mercury
in
the
system)
is
required.

2.
Mercury
separation/
removal
The
presence
of
mercury
complicates
the
design
of
off­
gas
systems,
the
stabilization
of
residuals,
and
the
monitoring
of
effluents
from
thermal
systems.
Removing
the
mercury
as
a
pretreatment
to
simplify
downstream
operations
may
be
advantageous.
New
techniques
must
be
developed
to
remove
(
physically
or
chemically)
the
mercury
for
separate
stabilization.
Waste
matrices
from
which
mercury
separation
may
be
required
include
soil,
all
types
of
process
residues
or
sludges
and
particulate
materials,
and
debris.
Processing
methods
must
ensure
adequate
removal
and
must
include
measuring
and
monitoring
methods
to
control
and
verify
the
process.

3.
Mercury
amalgamation
Elemental
mercury
may
be
derived
as
a
product
of
retorting
waste
containing
high
mercury
levels
(>
260
ppm)
or
recovered
from
the
off
gas
of
a
thermal
treatment
unit,
adding
to
the
elemental
mercury
streams
already
in
inventory.
Radioactive
mercury
can
probably
not
be
completely
purified
and
verified
for
recycle.
Disposal
of
the
mercury
will
require
amalgamation
to
form
a
stable,
insoluble
product.
Methods
and
equipment
designs
are
required
for
amalgamating
bulk
nonrecyclable
mercury.
2.4
How
Much
Waste
is
There?

Mercury­
contaminated
wastes
in
many
forms
are
present
at
virtually
every
U.
S.
Department
of
Energy
(
DOE)
facility
in
the
United
States.
In
addition
to
elemental
mercury,
these
waste
streams
include
sludges,
soils,
and
debris
waste,
with
mercury
concentrations
ranging
from
<
2
ppm
to
>
50,000
ppm.
Estimates
of
the
inventories
of
mercury­
contaminated,
mixed
low­
level,
and
transuranic
(
TRU)
wastes
in
the
DOE
complex,
based
on
efforts
led
by
the
TRU
and
Mixed
Waste
Focus
Area
(
TMFA)
and
its
Mercury
Working
Group
(
HgWG),
are
as
follows
(
Conley
et
al.
1998):

­
Approximately
6
m3
of
liquid
elemental
mercury
­
Approximately
6,000
m3
of
mercury
wastes
contaminated
with
<
260
ppm
mercury
­
Approximately
38,000
m3
contaminated
with
³
260
ppm
mercury
and
with
radionuclides
Additional
inventories
of
elemental
mercury
will
be
generated
at
planned
treatment
facilities
such
as
the
Defense
Waste
Processing
Facility
at
the
Savannah
River
Site
and
the
Advanced
Mixed
Waste
Treatment
Facility
at
the
Idaho
National
Environmental
Engineering
Laboratory
(
INEEL).
In
addition,
treatment
of
other
mercury
wastes
(
e.
g.,
soil,
debris)
through
IMERC
and
retort
RMERC
will
result
in
additional
volumes
of
elemental
mercury
requiring
stabilization.

The
Department
of
Energy
(
DOE)
is
storing
approximately
145
tons
of
mercury
(
not
including
the
amount
being
stored
in
Y12
for
the
DLA
program).
DOE
has
identified
5
tons
of
mercury­
contaminated
wastes
currently
awaiting
disposal
as
part
of
an
ongoing
inventory
of
such
wastes.

2.5
Previous
Studies
on
Treatment
of
Mercury­
Contaminated
Wastes
Recognizing
the
current
deficiencies
in
the
current
required
methods
of
treatment
on
radioactive
waste
contaminated
with
mercury,
the
Department
of
Energy
initiated
several
studies,
with
EPA's
participation.
The
studies
were
laid
out
in
a
in
a
technology
development
plan,
leading
to
the
execution
of
three
technology
demonstration
campaigns:

­
MER01
 
Demonstration
of
the
Amalgamation
Process
for
Treatment
of
Radioactively
Contaminated
Elemental
Mercury
Wastes
­
MER02
 
Demonstration
of
the
Stabilization
Process
for
Treatment
of
Radioactively
Contaminated
Mercury
(<
260
ppm)
Wastes
­
MER03
 
Demonstration
of
the
Stabilization
Process
for
Treatment
of
Radioactively
Contaminated
Mercury
(>
260
ppm)
Wastes
The
Transuranic
and
Mixed
Waste
Focus
Area
(
DOE)
issued
solicitations
to
industry
for
the
MER01
demonstration
campaign
in
November
1996,
for
MER02
in
January
1998,
and
for
MER03
in
February
1999
to
identify
vendors
with
technologies
that
could
be
used
to
overcome
the
treatment
deficiencies.
The
goal
of
the
three
campaigns
is
to
demonstrate
the
effectiveness
of
newly
developed
technologies
that
can
achieve
the
following:
­
Ensure
adequate
treatment
via
amalgamation,
stabilization,
or
thermal
treatment
­
Include
measuring
and
monitoring
methods
to
control
and
verify
the
process
­
Minimize
worker
exposure
­
Minimize
secondary
waste
generation
­
Maximize
operational
flexibility
and
radionuclide
containment
The
MER01,
MER02,
and
MER03
solicitations
targeted
the
most
promising
potential
treatment
technologies
for
mercury­
contaminated
wastes.
Stabilization
is
of
interest
for
radioactively
contaminated
mercury
waste
(<
260
ppm
mercury)
because
of
its
success
with
particular
wastes,
such
as
soils,
and
its
promise
of
applicability
to
a
broad
range
of
wastes.
For
the
same
reasons,
stabilization
is
also
of
interest
for
waste
with
higher
contamination
levels
(>
260
ppm
mercury)
as
a
possible
alternative
to
the
thermal
treatment
technologies
currently
prescribed
by
law.
In
either
case,
however,
stabilization
methods
must
be
proven
to
be
adequate
to
meet
treatment
standards.
They
must
also
be
proven
feasible
in
terms
of
economics,
operability,
and
safety.
At
the
time
of
the
solicitations,
no
standard
method
of
stabilization
had
been
developed
and
proven
for
such
varying
waste
types
as
those
within
the
DOE
complex.

2.5
Current
Study
 
Wastes
Containing
High
Mercury
(
MER04)

The
MER04
study
is
a
continuation
of
the
earlier
studies
of
the
treatment
of
mercurycontaminated
waste.
The
MER04
study
was
initiated
and
administered
by
EPA,
in
consultation
with
DOE.
The
study
started
with
a
solicitation
to
industry
from
January
2001
entitled,
"
Demonstration
Of
The
Stabilization
Process
For
Treatment
Of
Mercury
Sludge
Wastes
Containing
>
260
ppm
Mercury."
This
study
is
designed
to
supplement
the
data
on
treatment
of
soils,
by
providing
additional
data
for
stabilization
of
high­
mercury
subcategory
waste
sludges.
The
data
gathered
from
the
demonstration
of
treatment
of
this
sludge
should
then
provide
EPA
with
enough
information
to
support
a
revision
to
allow
stabilization
of
all
high
Hg
subcategory
wastes.
This
effort
had
two
major
objectives.

1.
To
evaluate
alternative
processes
to
RMERC
and
IMERC
for
DOE's
legacy
mixed
waste.
To
that
end,
the
processes
will
treat
a
high
Hg
subcategory
surrogate
waste
to
meet
a
TCLP
treatment
goal
of
0.025
mg/
L
or
less.
A
non­
radioactive
surrogate
waste
sludge
had
been
selected
to
eliminate
the
added
cost
and
requirements
for
handling,
treatment,
and
disposal
of
an
actual
radioactive
mixed
waste.
The
surrogate
sludge
contained
five
different
forms
of
mercury
including
elemental.

2.
To
provide
EPA
with
the
treated
waste
forms
that
EPA
could
test
to
compare
proposed
new
analytical
protocols
to
the
standard
TCLP
results,
and
to
assess
suitable
disposal
environments
for
the
wastes
forms.
These
comparisons
will
be
used
by
EPA
in
their
efforts
to
revise
the
LDR
treatment
standards
for
mercury­
bearing
hazardous
wastes.

Technology
vendors
participated
in
this
demonstration
at
their
expense
except
for
the
analytical
costs
incurred
from
the
use
of
an
outside
laboratory
to
perform
the
surrogate
waste
characterization,
TCLP
testing
on
the
treated
waste
forms
and
the
costs
of
shipping
the
treated
waste
forms
to
ALTER,
Inc.,
where
the
fixed
pH
leaching
was
performed
and
to
Oak
Ridge
National
Laboratory
(
ORNL)
where
vapor
pressure
testing
will
occur.
The
results
of
the
Oak
Ridge
National
Laboratory
testing
will
be
presented
in
a
separate
report.
ALTER
provided
the
raw
materials
and
the
protocols
to
make
up
the
surrogate
waste.
3.
Detailed
Description
of
Study
3.1
Overall
Plan
Mercury
contamination
exists
in
various
forms,
such
as
soil,
sludges,
and
debris,
and
in
various
species,
such
as
organic,
inorganic,
and
elemental.
The
objective
of
this
investigation
is
to
provide
information
on
the
ability
of
current
technologies
to
convert
mercury­
containing
wastes
into
a
stable
waste
form
for
disposal.
Each
of
the
current
technologies
relies
on
chemical
reactions
to
minimize
volatilization
and
solubility,
as
opposed
to
recovery
or
separation
technologies
which
generate
a
near
mercury­
free
residual
in
addition
to
concentrated
or
purified
mercury.

EPA
and
DOE
are
investigating
possible
stabilization
methods
for
mercury­
contaminated
waste
and
mixed
waste
streams.
These
methods
are
`
nonthermal,'
occurring
at
conditions
below
the
boiling
point
of
mercury
(
357
E
C
or
675
E
F).
To
investigate
the
ability
of
these
technologies
to
effectively
treat
wastes,
EPA
designed
a
detailed
project
plan
(
EPA
Quality
Assurance
Project
Plan
 
Technical
Support
for
Amendment
of
Land
Disposal
Restrictions
for
Mercury
Wastes,
December
2000
[
QAPP]
Appendix
A).
EPA
planned
to
synthesize
a
`
surrogate
waste,'
for
subsequent
treatment
by
each
of
several
different
vendors.
This
surrogate
is
intended
to
be
representative
of
many
complex
sludges
awaiting
treatment
at
DOE
facilities.
The
resulting
treated
wastes
would
each
undergo
a
rigorous
set
of
procedures
to
better
understand
the
performance
of
the
technology.
In
addition
to
reducing
mercury
mobility,
the
process
should
minimize
worker
exposure,
minimize
volume
increase
as
waste
is
treated,
minimize
secondary
waste
generation,
and
maximize
operational
flexibility.

In
completing
this
project,
a
coordinated
effort
was
required
between
technology
vendors,
laboratories,
DOE/
ORNL,
and
EPA.
Key
participants
in
the
project
were
as
follows:

­
Treatment
technology
vendors
 
Four
vendors
were
selected
by
EPA
as
participants
in
the
study.
Detailed
discussion
of
their
roles,
technologies,
and
activities
are
discussed
in
Chapter
4
of
this
report.
Responsibilities
of
the
vendors
included
receiving
the
untreated
waste
components,
mixing,
treating
the
surrogate
waste
using
bench
scale
technology,
and
sending
the
treated
waste
back
to
the
laboratory.

­
The
Accelerated
Life
Testing
and
Environmental
Research
(
ALTER)
Corporation,
Dillsboro,
IN
 
ALTER's
responsibilities
included
preparation
of
the
QA
plan,
preparing
the
surrogate
waste
components
for
distribution
to
the
vendors,
receiving
the
treated
wastes,
and
conducting
leaching
tests
of
the
resulting
treated
wastes.

­
Environmental
Enterprises,
Inc.,
Cincinnati,
Ohio
 
Environmental
Enterprise
Incorporated
was
responsible
for
conducting
mercury
analysis
of
solid
and
aqueous
(
i.
e.,
leachate)
matrices
(
Appendices
B
and
E).

­
Agvise
Laboratories,
Northwood,
ND
 
Agvise
was
responsible
for
testing
physical
characteristics
of
the
treated
waste.
These
tests
include
bulk
density,
moisture
content,
percent
organic
matter,
cation
exchange
capacity,
particle
size
distribution
and
infiltration
rate
testing
(
Appendix
C).
The
Agvise
testing
uses
standard
methods
for
soils,
established
by
the
USDA
and
the
Soil
Society
of
America
(
Appendix
D).

­
Oak
Ridge
National
Laboratory,
Oak
Ridge,
TN
 
ORNL
was
responsible
for
the
measurement
of
the
mercury
vapor
pressure
at
20
E
C
and
60
E
C
of
treated
waste.
ORNL
results
will
be
reported
separately.

Activities
performed
by
these
parties
are
described
below
in
more
detail.
These
activities
include
preparing
a
surrogate
sludge
for
evaluation
and
treatment
and
characterizing
both
the
untreated
surrogate
sludge
and
treated
waste.
Activities
relating
to
the
treatment
itself
are
discussed
in
detail
in
Section
4
of
this
report.

3.1.1
Surrogate
Sludge
Preparation
A
laboratory
scale
surrogate
mercury
sludge
was
assembled
by
ALTER
for
use
in
this
evaluation.
The
surrogate
sludge
was
intended
to
be
a
`
difficult
to
treat'
mercury­
containing
waste
representative
of
the
wide
range
of
such
wastes
that
would
require
treatment.
The
components
of
the
final
surrogate
waste
included
an
organic
form
of
mercury
(
i.
e.,
phenyl
mercuric
acetate),
elemental
mercury,
and
mercury
salts
(
i.
e.,
mercuric
chloride,
mercuric
oxide,
and
mercuric
nitrate)
in
an
inorganic
matrix.
The
overall
mercury
concentration
was
0.5
percent.
The
sludge
composition
is
outlined
in
Table
3­
1.
EPA
initially
considered
including
a
small
percentage
(
1
percent)
of
motor
oil
in
the
surrogate
mercury
sludge
for
two
reasons:
(
1)
oils
may
be
present
in
mercury­
containing
wastes,
and
(
2)
the
additional
oil
would
be
expected
to
create
an
even
more
`
difficult
to
treat'
matrix.
However,
when
conducting
preliminary
testing
of
such
a
surrogate
waste,
EPA
could
not
achieve
its
performance
criteria
for
mercury
analysis.
Therefore,
motor
oil
was
not
part
of
the
final
surrogate
composition
that
was
sent
to
vendors
for
treatment.

The
surrogate
was
shipped
as
pre­
measured
components
to
be
blended
by
the
vendors.
Vendors
were
responsible
for
mixing
the
surrogate
from
the
components
shipped
by
ALTER.
Table
3­
1
Final
Surrogate
Sludge
Composition
Sludge
Constituent
Weight
Percent
Mercury
Target
Concentration,
ppm
Phenyl
Mercuric
Acetate
0.08
500
Mercury
Nitrate
0.17
1000
Elemental
Mercury
0.15
1500
Mercury
Oxide
0.11
1000
Mercury
Chloride
0.14
1000
Diatomaceous
Earth
20
0
Aluminum
Hydroxide
10
0
Ferric
Chloride
10
0
Sodium
Chloride
10
0
Water
49.35
0
Total
100
5000
3.1.2
Baseline
Characterization
ALTER
prepared
a
sample
of
the
waste
sludge
described
above
for
testing
and
analysis.
The
purpose
of
this
was
to
provide
a
baseline
for
comparison
with
the
treated
waste
received
from
the
vendors.
Both
the
baseline
material
and
the
treated
wastes
obtained
from
the
vendors
underwent
identical
testing
and
analysis.
Deviations
between
wastes
from
different
vendors
or
from
the
baseline
are
detailed
in
Section
4
of
this
report.

At
ALTER,
sludge
was
mixed
in
three­
liter
batches
in
a
five
quart
Hobart
mixer.
Mercury
species
as
listed
in
Table
3­
1
were
added
only
after
the
major
constituents
had
been
well
blended.
Samples
of
blended
waste
were
characterized
as
described
in
Section
3.2
of
this
report.

3.1.3
Treated
Waste
Characterization
Four
commercial
vendors
returned
the
treated
waste
to
ALTER
for
testing.
The
vendor
treated
wastes
were
characterized
and
subjected
to
physical
and
chemical
analyses
to
determine
their
behavior
under
a
range
of
potential
disposal
conditions.

3.2
Physical
and
Chemical
Analysis
Samples
of
the
baseline
surrogate,
the
vendor­
mixed
surrogate
before
treatment,
and
the
treated
waste
generated
by
the
vendors
were
subjected
to
a
battery
of
physical
and
chemical
analyses.
The
treatment
technologies
used
by
the
vendors
are
described
in
Section
4.
Table
3­
2
summarizes
the
analyses
conducted
on
the
materials.
Table
3­
2
Test
Procedures
for
Surrogate
Waste
Project
Parameter
Reference
Laboratory
Matrices
Physical
characteristics:
density;
water
content;
particle
size;
infiltration
rate;
cation
ion
exchange
capacity;
percent
organic
matter;
cations
(
magnesium,
potassium,
calcium,
sodium)
Standard
Methods
for
Soils
established
by
the
USDA
and
the
Soil
Society
of
America.
Agvise
Laboratories
1,
2,
3
Mercury
analysis,
in
leachate
and
solid
matrices
SW
846
Method
7470A
Environmental
Enterprises
1,
2,
3;
all
leachates
Mercury
vapor
pressure
testing
Jerome
431
Arizona
Instruments
(
Phoenix,
AZ)
ORNL
3
pH
Standard
Methods
for
the
Examination
of
Water
and
Wastewater
4500
ALTER
All
leachates
Moisture
content
ASTM
D
2216­
80
ALTER
1,
3
TCLP
leaching
SW
846
Method
1311
ALTER
1,
3
Constant
pH
leaching
QAPP
Appendix
B
ALTER
1,
3
Matrices:
1:
surrogate
waste
as
mixed
by
ALTER.
2:
untreated
waste
as
prepared
by
each
vendor.
3:
treated
waste
prepared
by
each
vendor.

In
order
to
assess
the
stability
of
the
wastes,
several
leaching
procedures
were
performed
on
the
baseline
surrogate
and
vendor
treated
waste.
Leaching
tests
performed
by
ALTER
included
the
toxicity
characteristic
leaching
procedure
(
TCLP)
and
constant
pH
testing.
Upon
completion
of
each
leaching
test,
the
pH
of
the
leachate
was
recorded
and
leachate
samples
sent
to
Environmental
Enterprises
Incorporated
for
determination
of
their
mercury
content.
These
two
leaching
tests
are
discussed
below:

­
Toxicity
Characteristic
Leaching
Procedure
 
This
is
a
standard
regulatory
test
(
40
CFR
261.24,
SW­
846
Method
1311)
intended
to
determine
the
potential
mobility
of
contaminants
in
a
solid
waste
under
simulated
landfill
conditions.
The
TCLP
entails
an
initial
pH
measurement
of
the
waste
to
determine
the
appropriate
pH
of
the
extraction
fluid
to
be
used
in
at
20:
1
liquid/
solid
ratio
(
20
Kg/
1
L)
for
a
dynamic
contact
time
of
18
hours.
The
resulting
leachate
is
filtered
and
analyzed
for
mercury.

­
Constant
pH
Leaching
 
Constant
pH
leaching
tests
are
a
means
to
determine
the
effect
of
pH
on
the
stability
of
a
waste.
The
constant
pH
procedure
was
developed
by
ALTER
and
is
attached
as
Appendix
B
to
the
QAPP
(
presented
in
Appendix
A
of
this
report).
Samples
are
leached
in
a
constant
pH
solution
that
is
adjusted
to,
and
maintained
at,
the
desired
pH
end
point.
The
constant
pH
leaching
tests
were
performed
at
pH
values
of
2,
4,
6,
8,
10
and
12.
The
pH
is
maintained
by
automated
systems
(
designed
by
ALTER),
for
a
14
day
period,
at
which
point
the
resulting
leachate
is
filtered
and
analyzed
for
mercury.
A
20:
1
leachate
to
solids
ratio
was
used
in
these
tests.
The
longer
exposure
period
of
14
days
was
selected
to
ensure
equilibrium
conditions
were
obtained.
To
assess
the
effects
of
grinding
to
less
than
9.5
mm
on
a
macroencapsulated
waste
form,
additional
testing
was
performed
on
approximately
8
mm
cast
pellets
of
two
waste
forms.
Vendor
A
and
Vendor
B
each
submitted
two
waste
forms
for
testing:
(
1)
crushed
material
or
monolithic
material
to
be
crushed,
and
(
2)
pelletized
material.
The
pelletized
material
from
Vendor
A
differed
only
in
size.
Vendor
B
submitted
a
chemically
stabilized
crushed
material
and
that
same
chemically
stabilized
material
macroencapsulated
into
pellets.

3.3
Selection
of
Vendors
Four
waste
treatment
technology
vendors
participated
in
this
study.
These
vendors
were
selected
jointly
between
ORNL
and
EPA.
ORNL
prepared
the
statement
of
work
for
stabilization
vendors
and
evaluated
vendor
test
plans.

3.3.1
Statement
of
Work
On
January
26,
2001,
ORNL
issued
Request
for
Proposal
(
RFP)
No.
3400007805.
Following
evaluation
of
the
proposals,
three
vendors
were
initially
identified
for
participation
in
the
study.
A
fourth
participant
later
asked
to
participate
and
became
part
of
the
study.
The
four
vendors
are
identified
as
vendors
A,
B,
C
and
D.

ORNL
issued
contracts
with
each
of
the
vendors
using
a
statement
of
work
(
SOW).
The
requirements
of
the
vendors
expressed
in
the
SOW
included
the
following:

­
Types
of
processes
considered
 
The
mercury
stabilization
process
shall
stabilize
mercury
containing
wastes
without
removing
the
mercury
from
the
waste
matrix;
processes
that
involve
separating
the
mercury
from
the
waste
matrix
followed
by
amalgamation
are
not
within
the
scope
of
the
demonstration.

­
Effectiveness
towards
mercury
species
 
The
mercury
stabilization
process
must
stabilize
all
forms
of
mercury
including
organic
and
halogenated
mercury
compounds,
elemental
mercury,
mercury
oxides,
and
mercury
nitrates.

­
Treatment
wastes
 
The
mercury
stabilization
process
should
minimize
secondary
wastes.
The
waste
volume
increase
of
the
final
waste
form
due
to
the
stabilization
process
should
also
be
minimized.

­
Effects
from
heat
 
During
the
stabilization
process
demonstration,
a
chemical
reaction
may
result
that
increases
the
temperature
and
releases
undesired
offgases.
If
this
is
the
case,
the
demonstration
must
include
control
technology
to
ensure
waste
integrity
and
contain
both
mercury
and
organic
emissions.

­
Safety
and
health
 
The
stabilization
process
is
to
accomplish
mercury
stabilization
within
the
boundaries
of
worker
and
public
exposure
limits
as
required
by
OSHA
and
local
radiation
control
requirements.
Vendors
were
requested
to
perform
the
following
activities:

­
Prepare
a
plan
­
Prepare/
mix
surrogate
waste
using
the
individual
ingredients
supplied
by
ALTER
­
Conduct
TCLP
analysis
of
the
resulting
surrogate
­
Conduct
the
treatment
using
appropriately
scaled
equipment
­
Ship
treated
waste
passing
TCLP
to
ALTER
­
Prepare
report
3.3.2
Vendor
Test
Plans
Each
vendor
was
to
submit,
for
review
by
ORNL,
a
plan
for
treatment
of
the
surrogate
batches.
The
plan
included
the
following:

­
Mixing
method
­
Sample
containerization
and
preservation
­
Process
design
and
operating
data
collection
­
Total
mass
of
treatment
additives
Vendors
B
and
C
selected
by
ORNL
and
EPA
(
OSW)
received
two,
pre­
measured
50­
lb.
sets
of
surrogate
sludge
components.
Vendors
A
and
D
each
received
1
pre­
measured
set.
Vendors
were
responsible
for
mixing
the
surrogate
from
the
components
shipped
by
ALTER.
When
mixing
was
complete,
approximately
1
kg
of
untreated
waste,
consisting
of
a
composite
from
approximately
10
random
grab
samples,
was
to
be
collected
for
shipment
to
ALTER.
Following
treatment
of
each
batch,
vendors
were
to
submit
a
sample
of
each
batch
to
an
outside
lab
for
TCLP
testing,
and
return
the
successfully
treated
surrogate
sludge
to
ALTER
for
evaluation
and
testing.

At
ALTER,
the
treated
surrogate
was
to
be
crushed
if
necessary
to
pass
a
9.5
mm
sieve.
Crushed
treated
material,
or
material
passing
the
9.5
mm
sieve
was
then
blended
and
subsampled
using
a
sample
splitter,
for
each
test
to
be
performed.
4.
Treatment
Technologies
Each
of
the
technologies
used
by
the
four
vendors
involves
stabilization
of
the
surrogate
sludge.
ORNL
and
EPA
specifically
were
evaluating
technologies
which
immobilize,
rather
than
separate,
mercury
within
wastes.
Data
and
information
concerning
these
treatment
technologies
were
obtained
from
the
vendor
project
reports
submitted
to
EPA/
ORNL,
as
well
as
previously
prepared
technology
or
performance
descriptions
prepared
for
ORNL.

Detailed
descriptions
of
these
technologies
are
presented
in
this
section
of
the
report.
Similarities
and
differences
between
the
technologies
are
presented
in
Table
4­
1.

Table
4­
1
Summary
of
Technologies
Used
for
Surrogate
Sludge
Treatment
Comparison
Factor
Vendor
A
B
C
D
Process
Overview*
Formation
of
mercuric
sulfide
followed
by
thermoplastic
encapsulation
using
sulfur
polymer
stabilization/
solidification
process
Formation
of
mercuric
sulfide
with
micro­
and
macroencapsulation
Amalgamation
and
stabilization
process
of
elemental
Hg
followed
by
precipitation
of
stable
salt.
Formation
of
mercuric
sulfide
followed
by
cement­
containing
proprietary
stabilization
agent
Reagents
Added*
95%
sulfur
polymer,
5%
organic
modifier,
and
proprietary
additives
Sulfide
and
proprietary
binders
and
coating
agents
Amalgamation
agent
and
proprietary
precipitation
reagent
Sulfide
and
proprietary
cement­
containing
stabilization
agent
Waste
Loading
(
on
dry
basis)
30
wt%
72
wt%
Batch
1
44.9
wt%
Batch
2
47.0
wt%
25.4
wt%

Volume
and/
or
Weight
Increase
233%
by
weight
on
dry
basis
36%
on
volume
basis
38.9%
by
weight
on
dry
basis
Batch
1
123%
by
weight
Batch
2
113%
by
weight
25%
by
volume
294%
by
weight
Final
Form
of
Treated
Waste
Monolithic
Soil­
like
 
Stage
1
Monolithic
solid
spheres
 
Stage
2
Soil­
like
Monolithic
Mercury
Losses
to
Air
Estimated
0.3%
(
from
historical
data)
None
identified
Estimated
0.05%
None
identified
*
Several
vendors
use
reagent
and/
or
process
steps
which
have
been
claimed
to
be
confidential
business
information
(
CBI).
Only
non­
CBI
is
presented
in
this
report.
4.1
Treatment
of
Surrogate
 
Vendor
A
Vendor
A
used
its
proprietary
sulfur
polymer
stabilization/
solidification
(
SPSS)
process
for
treating
the
surrogate
waste.
The
purpose
of
this
process
is
to
chemically
stabilize
and
physically
encapsulate
mercury
to
reduce
vapor
pressure
and
leachability.
This
process
is
conducted
in
two
stages.
The
first
step
is
a
reaction
between
elemental
mercury
and
mercury
compounds,
sulfur
polymer
cement
and
additives
to
generate
mercuric
sulfide
(
HgS).
(
Sulfur
polymer
cement
consists
of
95
weight
percent
elemental
sulfur
reacted
with
five
weight
percent
of
an
organic
modifier.)
During
reaction,
the
vessel
is
placed
under
inert
atmosphere
to
prevent
mercuric
oxide
(
HgO)
formation
(
a
compound
much
more
environmentally
mobile
than
mercuric
sulfide)
and
heated
to
40
E
C
to
enhance
the
sulfide
formation.
The
purpose
of
this
first
step
is
to
chemically
stabilize
the
mercury.
After
sulfide
formation,
the
waste
is
removed.

The
purpose
of
the
second
step
is
to
solidify
the
product.
The
mixture
is
heated
to
130
E
C
to
melt
the
thermoplastic
sulfur
binder.
It
is
then
poured
into
a
mold.
On
cooling,
the
reacted
sulfide
particles
become
microencapsulated
within
the
monolithic
sulfur
matrix.

Pilot­
scale
SPSS
processing
was
accomplished
using
a
1­
ft3,
oil­
heated,
vertical
cone
mixer.
Mixing
action
is
provided
by
a
24­
inch
long
auger
screw.
Feed
materials
were
charged
to
the
unit
through
a
6­
inch
diameter
port
on
the
cone
lid
with
the
auger
screw
drawing
material
upward
from
the
base
of
the
cone.
When
mixing,
the
system
was
purged
with
an
inert
gas
by
connection
to
a
regulated
nitrogen
gas
supply.
Heat
was
provided
to
the
jacketed
cone
by
a
circulating
fluid
heat
transfer
system.
A
heated
ball
valve
at
the
base
of
the
cone
was
used
to
discharge
the
molten
SPSS
product.

Off­
gas
was
controlled
by
a
sequence
of
a
heat
exchanger,
a
liquid
nitrogen
trap,
and
HEPA/
charcoal
filters
prior
to
atmospheric
discharge.
Other
than
periodic
monitoring
of
the
stack
gases,
Vendor
A
did
not
measure
mercury
air
releases
during
processing
of
the
surrogate
sludge.
In
earlier
demonstrations
of
treatment
of
elemental
mercury
and
mercury­
contaminated
soils,
a
mercury
mass
balance
demonstrated
that
0.3%
of
mercury
was
volatilized
and
captured
in
the
offgas
collection
system.

Each
batch
of
surrogate
sludge
(
batch
1
without
Hg,
to
assess
mixing
characteristics,
and
batch
2
with
Hg)
was
prepared
in
a
45­
liter
polyethylene
container.
(
Approximately
3
liters
of
water
were
kept
separate
prior
to
mixing,
to
use
as
rinse
water,
where
needed.)
The
soluble
salts
(
first
ferric
chloride,
then
sodium
chloride)
were
dissolved
in
de­
ionized
water,
followed
by
addition
of
the
aluminum
chloride
and
diatomaceous
earth.
The
material
was
mixed
with
a
steel
mixing
blade.
The
sludge
thickened
significantly
during
addition
of
the
diatomaceous
earth.
Approximately
15
minutes
were
required
to
complete
addition
of
these
four
major
constituents,
after
which
the
batches
were
stirred
another
15
minutes
to
ensure
homogenization.
The
second
batch
(
Batch
No.
2)
continued
to
be
stirred
an
additional
15
minutes
while
the
five
mercury
components
were
added.
The
sludge
was
very
corrosive,
resulting
in
severe
attack
on
the
mixing
blade.
The
pH
of
the
sludge
was
measured
to
be
0.98.

Two
1­
liter
samples
of
the
mercury­
spiked
sludge
surrogate
were
collected
for
bench­
scale
process
experiments,
approximately
5
hours
after
addition
of
the
mercury
compounds.
Pretreatment
grab
sampling
was
done
several
weeks
later,
just
prior
to
pilot­
scale
processing.
In
both
cases
the
sludge
was
mixed
for
a
minimum
of
15
minutes
to
ensure
homogeneity,
and
was
then
pumped
using
a
peristaltic
pump
from
the
50­
lb
batch
as
it
was
being
mixed.

Vendor
A
submitted
two
physical
forms
of
treated
waste
(
both
from
batch
2)
to
ALTER
for
testing.
The
first
waste
form
was
created
by
allowing
the
molten
material
to
solidify
in
bulk.
The
second
waste
form
submitted
for
testing
by
Vendor
A
was
pelletized.
To
prepare
the
pellets,
monolithic
material
was
heated
to
approximately
140
E
C
and
poured
into
Teflon
molds
to
create
small
pellets
approximately
8­
mm
in
diameter
by
8­
mm
in
length.
This
dimension
was
selected
so
that
the
material
would
meet
the
9.5
mm
particle
size
requirement
for
TCLP
testing.
The
bulk
(
monolithic)
material
was
crushed
at
ALTER,
using
a
commercial
compression
machine
to
yield
<
9.5mm
pieces
for
parallel
TCLP
and
constant
pH
testing.
Both
the
pellet
and
crushed
forms
were
tested
in
parallel
throughout
the
evaluation.

4.2
Treatment
of
Surrogate
 
Vendor
B
Vendor
B
used
a
three­
step
process
to
stabilize
the
surrogate.
This
is
a
three
step
process
that
can
be
tailored
to
meet
product
specification
desired
by
a
client.
The
first
step
(
primary
stabilization)
involves
reaction
of
the
mercury
contained
in
the
bulk
waste
matrix
to
form
a
mercuric
sulfide
product
that
meets
the
TCLP
UTS
for
mercury.
The
second
stage
of
the
process
involves
addition
of
binders.
In
the
third
stage,
coating
agents
are
added
to
render
a
final
waste
form
that
is
nominally
spherical
with
a
top
size
diameter
of
9.5
mm.

On
a
dry
basis
the
final
product
contained
72
wt­%
of
the
surrogate
feed
material.

4.3
Treatment
of
Surrogate
 
Vendor
C
Vendor
C
used
an
ambient
temperature
process,
developed
to
treat
elemental,
ionic,
and
complexed
forms
of
mercury
in
mixed
(
radioactive
and
hazardous)
waste.
Vendor
C
has
previously
permitted
and
operated
this
process
for
treatment
of
mercury­
contaminated
mixed
wastes.
The
surrogate
sludge
testing
was
conducted
using
a
pilot­
scale
reactor
capable
of
handling
up
to
45­
kg
of
soil
and
reagents.
Test
parameters,
reagent
dosages,
and
processing
equipment
were
selected
based
on
previous
experience.
Soil
feed
and
stabilizing
reagents
were
metered
directly
into
the
reactor.
For
mercury­
containing
wastes,
mixing
methods
become
important
in
dispersing
amalgamating/
stabilizing
reagents
to
all
sites
within
the
matrix
that
contain
the
mercury
contamination.

Prior
to
treatment
with
additives,
it
is
sometimes
necessary
to
condition
waste
by
shredding,
grinding,
and/
or
slurrying
with
water.
This
determination
is
made
based
on
the
capability
of
the
mixing
equipment
to
be
used.
For
the
surrogate
sludge,
Vendor
C
indicated
that
pretreatment
was
necessary
but
did
not
identify
what
type
of
activity
was
conducted.
Vendor
C
added
only
25%
water
in
assembly
of
the
surrogate,
not
the
49.35%
specified
in
the
instructions.

Two
batch
runs
were
performed
on
the
material
in
aliquots
of
50
pounds
each.
The
first
stage
of
the
process
involves
amalgamation
of
the
elemental
mercury
component.
For
matrices
such
as
soil,
sulfur
is
used
as
the
amalgamation
agent.
The
second
stage
of
the
process
is
the
stabilization
of
soluble
mercury
species
using
the
proprietary
reagent.
This
reagent
has
the
capability
to
free
mercury
from
stable,
soluble
complexes
and
subsequently
allow
for
its
precipitation
as
a
stable,
non­
leachable
salt.
More
specific
details
on
the
additives
used
for
the
amalgamation
or
the
stabilization
step
were
claimed
as
confidential
business
information
(
CBI).

Following
treatment
of
the
surrogate
waste,
each
batch
was
mechanically
discharged
from
the
reactor.
The
final
waste
form
is
best
described
as
a
soil­
like
product
containing
no
freestanding
water.
The
weight
of
the
treated
surrogate
was
increased
by
about
60
percent.
This
is
much
greater
than
the
15
to
20
percent
increase
typically
seen
for
soil
treated
by
the
process.
The
difference
was
potentially
due
to
the
extremely
high
soluble
salt
content
of
the
surrogate
matrix.

During
the
course
of
the
demonstration,
Vendor
C
also
monitored
airborne
mercury
concentrations
using
a
Jerome
mercury
vapor
analyzer.
The
average
mercury
concentration
measured
in
the
contained
work
area
was
at
all
times
less
than
the
American
Conference
of
Governmental
Industrial
Hygienists
(
ACGIH)
threshold
limit
value
(
TLV)
of
0.025
mg/
m3
for
mercury
vapor.
This
is
the
most
stringent
of
applicable
enforceable
and
non­
enforceable
standards
for
mercury
exposure
from
ACGIH,
the
Occupational
Safety
and
Health
Administration
(
OSHA),
and
the
National
Institute
for
Occupational
Safety
and
Health
(
NIOSH).
The
reported
mercury
levels
are
an
average
of
the
room
readings
(
taken
from
the
center
of
the
structure)
and
an
average
of
the
batch
mixer
readings
(
taken
directly
over
the
batch
mixer
and
in
its
opening).

These
airborne
mercury
levels
were
used
to
estimate
the
quantity
of
mercury
evolved
during
processing.
Using
a
conservative
flow­
rate
for
the
designated
containment
area,
Vendor
C
estimates
that
a
maximum
of
0.05%
of
the
initial
inventory
of
mercury
evolved
during
this
demonstration.
Therefore,
approximately
99.95%
of
the
mercury
input
to
the
process
was
retained
within
the
processing
system.

4.4
Treatment
of
Surrogate
 
Vendor
D
Vendor
D
treated
two
50
pound
batches
of
surrogate
material,
using
the
same
procedure
for
each.
In
making
each
surrogate
batch,
Vendor
D
first
mixed
the
elemental
mercury
separately
with
a
small
quantity
of
dry
ingredients,
which
were
then
mixed
into
the
sludge.
This
was
conducted
in
an
effort
to
better
disperse
the
mercury.
After
preparation
of
the
sludge,
a
sulfide
solution
was
added
to
each
50­
lb
batch
of
surrogate
material
and
mixed
for
15
minutes.
Then,
50
pounds
of
a
proprietary
cement
containing
stabilization
agent
was
added
and
mixed.
Approximately
30
minutes
was
required
for
a
batch
cycle:
5
minutes
to
pour
the
sludge
into
the
mixer,
5
minutes
to
add
and
mix
the
sulfide
solution,
15
minutes
to
add
and
mix
the
stabilization
agent,
and
5
minutes
to
pour
the
treated
waste
out
of
the
mixer.
Samples
for
laboratory
testing
were
collected
after
all
stabilization
components
were
mixed
in.
The
remainder
of
the
treated
material
was
poured
into
a
62­
quart
cooler
lined
with
a
plastic
bag
(
the
final
volume
of
the
treated
material
was
approximately
2
cubic
feet).
Temperature
increases
were
observed
during
curing.
Despite
this
observation,
Vendor
D
anticipates
that
temperature
control
is
unlikely
to
be
required
during
mixing.
During
curing,
temperature
control
is
expected
to
be
adequate
if
at
least
one
linear
dimension
of
the
final
waste
form
is
less
than
1.5
feet.
No
data
or
measurements
were
available
concerning
airborne
mercury
releases
during
treatment.

The
final
waste
form
material
in
the
cooler
was
cured
for
one
month
and
then
shipped
to
ALTER,
with
small
samples
for
vapor
testing
shipped
to
Oak
Ridge
National
Laboratory.
The
consistency
of
the
treated
sludge
was
similar
to
a
pliable
clay
for
one
week
after
treatment,
during
which
the
internal
temperature
remained
at
about
85
°
C.
After
one
week
the
material
cooled
and
set
to
a
very
hard
concrete.
The
volume
increase
resulting
from
addition
of
stabilization
materials
to
the
surrogate
sludge
was
small,
less
than
25
percent.
5.
Leaching
Results
Samples
of
both
the
treated
and
untreated
surrogate
waste
from
each
vendor
were
leached
according
to
both
the
TCLP
and
the
constant
pH
leaching
protocol.
Mercury
concentrations
were
measured
on
the
unleached
material
(
untreated
surrogate
and
treated
waste
forms),
and
on
the
leachates
generated.
Section
5.1
presents
the
leaching
data
for
the
untreated
surrogate.
Sections
5.2
to
5.5
present
the
leaching
data
for
the
waste
forms,
by
vendor.

5.1
Untreated
Surrogate
Table
5­
1
summarizes
results
for
total
mercury
recovered
from
the
digested
solids
representing
the
untreated
surrogate
waste
form
and
the
TCLP
tests.
The
amount
of
mercury
recovered
from
the
digested
solids
is
less
than
the
true
loading
of
5,000
mg/
kg,
and
the
standard
deviation
and
coefficient
of
variation
(
CV)
indicate
moderate
variation
in
the
measured
results.
All
of
the
untreated
samples
fail
the
TCLP
test,
as
expected
for
an
untreated
mercury
waste
form.

Table
5­
1
Analytical
Results
for
the
Untreated
Surrogate
EEI
Work
Order
01­
05­
904
Sample
Total
Hg
(
mg/
kg)
Percent
Recovery
Sample
Final
pH
TCLP
(
mg/
L)
Percent
Leached1
Percent
Leached2
Surrogate
TCLP
1
4,660
93.2
1
3.82
113
45.2
56.9
2
3,250
65.0
2
3.65
107
42.8
53.9
3
3,640
72.8
3
3.63
111
44.4
55.9
4
4,090
81.8
4
3.63
109
43.6
54.9
5
4,230
84.6
­
­
­
­

Average
3,974
79.5
Average
110
44.0
55.4
Std.
Dev.
544
­
Std.
Dev.
2.58
­
­

CV
13.7
­
CV
2.35
­
­

1
Calculated
based
on
the
theoretical
total
mercury
content
(
5000
mg/
kg).
2
Calculated
based
on
the
average
total
mercury
content
for
the
solids.

The
amount
of
mercury
recovered
by
the
TCLP
test
is
reported
as
percent
leached,
and
is
based
on
the
average
or
theoretical
mercury
concentration
for
the
solid
sample.
Approximately
50
percent
of
the
mercury
is
leached
from
the
solid.
Percent
leached
is
calculated
as
follows:

[(
mg
Hg/
L
leachate)/(
mg
Hg/
kg
sample/
20]
*
100
where
mg
Hg/
L
is
the
TCLP
result,
mg
Hg/
kg
sample
is
the
mercury
concentration
in
the
solid,
and
20
is
the
liquid/
solid
ratio
of
the
leaching
test.
The
data
are
presented
based
on
both
the
theoretical
and
measured
concentration
of
mercury
in
the
solid.

Results
for
the
constant
pH
leach
tests
are
tabulated
in
Table
5­
2
and
plotted
on
Figure
5­
1
as
the
concentration
of
mercury
that
leached,
along
with
the
concentration
in
the
TCLP
leachate.
The
constant
pH
leaching
data
are
also
presented
in
Figure
5­
2
as
the
percentage
of
mercury
that
leached.
Table
5­
2
reports
the
analytical
results,
the
amount
of
mercury
removed
from
the
solid
(
percent
leached),
and
the
total
volume
of
leachate,
including
the
reagents
added
to
maintain
the
indicated
pH.
Duplicates
were
run
at
pH
values
of
2,
8,
and
12.
Relative
percent
difference
(
RPD)
for
the
experimental
duplicates
meet
the
QA
criteria
of
±
50
percent.
The
duplicate
values
appear
with
the
calculated
average
on
Figures
5­
1
and
5­
2,
and
the
trend
is
drawn
through
the
calculated
average.
Laboratory
QA/
QC
(
Appendix
E)
indicates
the
analytical
results
are
valid
as
reported.

Table
5­
2
Constant
pH
Leaching
Results
for
ALTER
Constructed
Untreated
Surrogate
EEI
Work
Order
01­
05­
904
pH
Hg
conc.
(
mg/
L)
Percent
Leached1
Percent
Leached2
Leachate
Volume3
(
mL)
RPD
Sample
Dups.

2
126
50.9
64.1
505.26
0.80
2
125
50.7
63.8
507.03
4
25.7
11.2
14.1
543.94
6
23.5
10.2
12.9
542.24
8
22.0
9.5
12.0
540.38
14.6
8
19.0
7.8
9.8
514.83
10
6.66
2.9
3.7
548.01
12
27.3
13.2
16.6
604.00
39.2
12
40.6
18.7
23.6
576.80
2
0.0520
­
­
502.73
Blank
1
Calculated
based
on
the
theoretical
total
mercury
content
(
5000
mg/
kg).
2
Calculated
based
on
the
average
total
mercury
content
in
the
solids.
3
Total
volume
of
leachate,
including
addition
of
NaOH
and/
or
HNO
3.

Percent
leached
is
calculated
according
to
the
equation
presented
for
the
TCLP
results,
using
the
leachate
volume
in
Table
5­
2
to
calculate
Liquid/
Solid
ratio.
Values
in
Table
5­
2
indicate
a
large
fraction
(
up
to
63
percent)
of
the
mercury
is
leached
from
the
solid
at
pH
2,
with
moderate
amounts
of
mercury
leached
over
the
pH
interval
of
4
to
12.

Figure
5­
1
shows
that
the
percentage
of
mercury
that
leached
from
the
sample
decreases
as
pH
increases
through
10,
and
then
rises
as
the
pH
increases
to
12.
There
is
little
change
in
the
mercury
concentration
over
the
pH
interval
of
4
through
8.
1
10
100
1000
0
2
4
6
8
10
12
14
pH
Hg
Conc.
(
mg/
L)
UTS
TCLP
1
10
100
0
2
4
6
8
10
12
14
pH
Percent
(%)
Leached
Untreated
Surrogate
Figure
5­
1
Constant
pH
Leaching
Results
for
ALTER
Constructed
Untreated
Surrogate
Concentration
Leached
Figure
5­
2
Constant
pH
Leaching
Results
for
ALTER
Constructed
Untreated
Surrogate
Percentage
Leached
5.2
Vendor
A
Table
5­
3
summarizes
results
for
total
mercury
recovered
from
the
digested
solids
representing
the
untreated
and
treated
waste
form
and
the
TCLP
tests.
The
additives
used
in
the
preparation
of
the
treated
waste
form
dilute
the
untreated
surrogate
and
lower
the
mercury
concentration
in
the
pellets
to
2,959
mg/
kg,
relative
to
the
theoretical
value
of
5,000
mg/
kg
for
the
untreated
wet
surrogate.
The
concentration
of
2,959
mg/
kg
is
obtained
by
taking
the
dry
weight
basis
(
1)
of
the
untreated
surrogate
(
9862
mg/
kg)
and
multiplying
it
by
the
surrogate
waste
loading
of
30%
(
9862*
0.3
=
2959
mg/
kg).

Table
5­
3
Analytical
Results
for
Vendor
A
EEI
Work
Order
01­
10­
674
Waste
form
TCLP
Sample
Total
Hg
(
mg/
kg)
Percent
Recovery1
Sample
Final
pH
TCLP
(
mg/
L)
Percent
Leached1
Percent
Leached2
Pellets
1
153
5.17
1
4.86
0.00116
0.000786
0.0115
2
73.5
2.48
2
4.91
0.00429
0.00290
0.0426
3
354
12.0
3
4.91
0.00223
0.00151
0.0222
4
243
8.21
3D
4.91
0.00237
0.00160
0.0235
5
183
6.19
­
­
­
­
Average
201
6.80
Average
0.00251
0.00170
0.0250
Std.
Dev.
105
­
Std.
Dev.
0.00130
­
­
CV
52.1
­
CV
35.9
­
­
Crushed
1
301
10.2
1
4.87
0.00266
0.00180
0.0120
2
312
10.6
2
4.87
0.00157
0.00106
0.00710
3
480
16.2
3
4.81
0.00142
0.00096
0.00642
4
615
20.8
­
­
­
­
5
504
17.0
­
­
­
­
Average
442
15.0
Average
0.00188
0.00127
0.00851
Std.
Dev.
134
­
Std.
Dev.
0.00068
­
­
CV
30.3
­
CV
35.9
­
­
Untreated
Surrogate
1
3910
78.2
­
­
­
­
2
4140
82.8
­
­
­
­
3
4700
94.0
­
­
­
­
Average
4250
85.0
­
­
­
­
Std.
Dev.
406
­
­
­
­
­
CV
9.56
­
­
­
­
­

1
Calculated
based
on
the
theoretical
total
mercury
content
of
2,959
mg/
kg
for
the
pellets.
2
Calculated
based
on
the
average
mercury
value
reported
for
the
pellets
and
crushed
material.
3
Calculated
based
on
the
theoretical
mercury
content
of
5,000
mg/
kg
for
the
surrogate.
For
the
TCLP
test,
the
pellets
and
crushed
fraction
show
similar
results
and
all
results
are
below
the
performance
goal
for
the
test
(
i.
e.,
less
than
0.025
mg/
L).
The
percentage
of
material
that
is
leached
from
the
solids
is
calculated
for
the
theoretical
loading
of
2,959
mg/
kg
for
the
pellets
and
for
the
average
total
mercury
value
measured
on
the
digested
treated
solids.
The
equation
used
to
calculate
the
values
was
presented
in
the
preceding
section.

Results
for
the
constant
pH
leach
tests
are
tabulated
in
Table
5­
4
and
plotted
on
Figure
5­
3
as
the
concentration
of
mercury
that
leached,
along
with
the
concentration
in
the
TCLP
leachate.
The
constant
pH
leaching
data
are
also
presented
in
Figure
5­
4
as
the
percentage
of
mercury
that
leached.
Table
5­
4
reports
the
analytical
results,
the
amount
of
mercury
removed
from
the
solid
(
percent
leached),
and
the
total
volume
of
leachate,
including
the
reagents
added
to
maintain
the
indicated
pH.
Duplicates
were
run
at
pH
values
of
2,
8
and
11
and
12.
Relative
percent
difference
(
RPD)
for
the
experimental
duplicates
do
not
meet
the
QA
criteria
of
±
50
percent,
with
the
exception
of
the
pellet
duplicates
at
pH
12
and
the
crushed
duplicates
at
pH
8.
The
duplicate
values
appear
with
the
calculated
average
on
Figures
5­
3
and
5­
4,
and
the
trend
is
drawn
through
the
calculated
average.
Laboratory
QA/
QC
(
Appendix
E)
indicates
the
analytical
results
are
valid
as
reported.

Table
5­
4
Constant
pH
Leaching
Results
for
Vendor
A
EEI
Work
Order
01­
10­
674
pH
Pellets
Crushed
RPD
Sample
Dups.
Hg
conc.
(
mg/
L)
Percent
Leached1
Percent
Leached2
Leachate
Volume3
(
mL)
Hg
conc.
(
mg/
L)
Percent
Leached1
Percent
Leached2
Leachate
Volume3
(
mL)

2
0.00251
0.00170
0.0249
501.57
0.00682
0.00461
0.0308
503.57
P
­
109
2
0.00856
0.00579
0.0850
500.94
0.00294
0.00199
0.0133
505.95
C­
79.5
4
0.00483
0.00327
0.0480
506.40
0.00555
0.00375
0.0251
503.40
6
0.00425
0.00287
0.0422
504.35
0.0140
0.00946
0.0633
503.50
8
0.0127
0.00859
0.13
504.17
0.00180
0.00122
0.0081
503.12
P­
99.9
8
0.00424
0.00287
0.042
502.10
0.00139
0.00094
0.0063
504.93
C­
25.7
10
0.00734
0.00496
0.073
556.12
0.00378
0.00256
0.0171
529.03
12
0.111
0.075
1.10
504.37
0.781
0.528
3.53
550.85
P­
34.3
12
0.157
0.106
1.56
504.72
0.136
0.0919
0.615
515.01
C­
141
2
<
0.00050
­
­
501.32
<
0.00050
­
­
506.50
Blank
1
Calculated
based
on
the
theoretical
total
mercury
content
of
2,959
mg/
kg
for
the
pellets.
2
Calculated
based
on
the
average
mercury
value
reported
for
the
pellets
and
crushed
material.
3
Total
volume
of
leachate,
including
addition
of
NaOH
and/
or
HNO
3.
0
.
0
0
1
0
.
0
1
0
.
1
1
1
0
0
2
4
6
8
1
0
1
2
1
4
pH
Percent
(%)
Leached
P
e
lle
t
s
Cru
s
h
e
d
0.001
0.01
0.1
1
10
100
1000
0
2
4
6
8
10
12
14
pH
Hg
Concentration
(
mg/
L)

Pellets
Crushed
Untreated
0.025
mg/
L
0.2
mg/
L
TCLP
Pellets
TCLP
Crushed
Figure
5­
3
Constant
pH
Leaching
Results
for
Vendor
A
Concentration
Leached
Figure
5­
4
Constant
pH
Leaching
Results
for
Vendor
A
Percentage
Leached
A
comparison
of
the
results
for
pellets
and
crushed
samples
shows
that
mercury
concentrations
are
similar
at
pH
2
and
4
and
different
at
pH
6,
8,
10
and
12.
Samples
representing
the
pellets
show
a
slow
increase
in
mercury
concentration
up
to
pH
10
and
then
an
abrupt
increase
between
pH
10
and
12.
The
crushed
samples
show
the
minimum
mercury
concentration
to
lie
at
pH
8
and
10,
and
then
a
sharp
jump
to
the
maximum
at
pH
12.

Percent
leached
is
calculated
according
to
the
equation
presented
for
the
TCLP
results,
using
the
leachate
volume
in
Table
5­
4
to
calculate
Liquid/
Solid
ratio.
Values
in
Table
5­
4
indicate
less
than
one
percent
of
the
theoretical
mercury
loading
is
released
to
the
solution.

The
amount
of
reagent
added
to
the
pH
10
tests
was
nearly
twice
as
much
for
the
pellet
test,
relative
to
the
crushed
test.
There
is
also
an
approximate
doubling
of
the
observed
mercury
concentration
for
the
pellet
test.
A
similar
pattern
is
seen
for
the
first
pH
12
test.
However,
when
data
from
all
the
vendors
is
examined,
there
is
no
clear
pattern
between
the
amount
of
reagent
added
and
the
reported
mercury
concentration.

5.3
Vendor
B
Table
5­
5
summarizes
results
for
total
mercury
recovered
from
digested
solids
representing
an
intermediate
waste
form
(
Phase
I),
the
final
treated
waste
form
(
Phase
II)
and
the
raw
surrogate.
The
reported
standard
deviation
and
CV
for
the
total
mercury
results
are
quite
low,
indicating
a
good
job
in
the
homogenization
of
the
wasteform.
Relative
to
the
amount
of
mercury
in
the
untreated
surrogate
(
5,000
mg/
kg
wet
or
9862
mg/
kg
dry
wt.
basis),
the
mercury
surrogate
loading
of
72%
by
weight
results
in
a
mercury
concentration
of
7,100
mg/
kg
(
9862
mg/
kg
x
0.72).
Note
that
the
vendor
prepares
the
waste
on
a
dry
weight
basis.
Recovery
of
the
mercury
from
the
Phase
I
waste
is
nearly
twice
that
of
the
Phase
II
material.
This
implies
the
digestion
used
to
characterize
the
mercury
loading
of
the
Phase
II
material
was
less
complete
then
that
carried
out
on
the
Phase
I
waste.
In
both
cases,
the
digestion
did
not
recover
the
total
mercury
loading.

The
TCLP
tests
yielded
fairly
uniform
results
for
each
of
the
phases,
as
expected
given
the
uniform
recovery
on
the
solids.
However,
all
of
the
mercury
concentrations
reported
for
the
TCLP
tests
did
not
meet
the
performance
goal
for
the
test
(
0.025
mg/
L).
TCLP
tests
were
not
performed
on
the
intermediate
Phase
I
solids.
The
percentage
of
material
that
is
leached
from
the
solids
is
calculated
for
the
theoretical
loading
of
7,100
mg/
kg
for
the
Phase
I
and
II
solids
and
for
the
average
total
mercury
value
measured
on
the
digested
treated
solids.
Table
5­
5
Analytical
Results
for
Vendor
B
EEI
Work
Order
01­
12­
039
&
01­
12­
515
Wasteform
TCLP
Sample
Total
Hg
(
mg/
kg)
Percent
Recovery1
Sample
Final
pH
TCLP
(
mg/
L)
Percent
Leached1
Percent
Leached2
Phase
I
Wasteform
1
4,350
61.3
1
5.53
0.140
0.0394
0.0646
2
4,610
64.9
2
5.63
0.165
0.0465
0.0761
3
4,470
63.0
3
5.79
0.161
0.0453
0.0743
4
4,310
60.7
­
­
­
­

5
3,940
55.5
­
­
­
­

Average
4,336
61.1
Average
0.155
0.0438
0.0716
Std.
Dev.
250
­
Std.
Dev.
0.0134
­
­

CV
5.8
­
CV
8.6
­
­

Phase
II
Wasteform
1
2,530
35.6
1
4.72
0.266
0.0749
0.201
2
2,690
37.9
2
4.73
0.150
0.0423
0.113
3
2,690
37.9
3
4.73
0.112
0.0315
0.0847
4
2,590
36.5
4
4.73
0.107
0.0301
0.0809
5
2,720
38.3
­
­
­
­

Average
2,644
37.2
Average
0.159
0.0447
0.120
Std.
Dev.
80.5
­
Std.
Dev.
0.07
­
­

CV
3.04
­
CV
46.6
­
­

Untreated
Surrogate
1
6,170
123
­
­
­
­

2
6,930
139
­
­
­
­

3
6,040
121
­
­
­
­

Average
6,380
128
­
­
­
­

Std.
Dev.
481
­
­
­
­
­

CV
7.53
­
­
­
­
­

1
Calculated
based
on
the
theoretical
total
mercury
content
of
7,100
mg/
kg
for
the
treated
waste.
2
Calculated
based
on
the
average
mercury
value
reported
for
the
Phase
I
and
II
material.
3
Calculated
based
on
the
theoretical
mercury
content
of
5,000
mg/
kg
for
the
surrogate.
Results
for
the
constant
pH
leach
tests
are
tabulated
in
Table
5­
6
and
plotted
on
Figure
5­
5
as
the
concentration
of
mercury
that
leached,
along
with
the
concentration
in
the
TCLP
leachate.
The
constant
pH
leaching
data
are
also
presented
in
Figure
5­
6
as
the
percentage
of
mercury
that
leached.
Table
5­
6
reports
the
analytical
results,
the
amount
of
mercury
removed
from
the
solid
(
percent
leached),
and
the
total
volume
of
leachate,
including
the
volume
of
reagents
added
to
maintain
the
indicated
pH.
Duplicates
were
run
at
pH
values
of
2,
8
and
11
and
12.
Relative
percent
difference
(
RPD)
for
the
experimental
duplicates
meet
the
QA
criteria
of
±
50
percent,
with
the
exception
of
the
Phase
II
sample/
duplicate
at
pH
2.
The
duplicate
values
appear
with
the
calculated
average
on
Figures
5­
5
and
5­
6,
and
the
trend
is
drawn
through
the
calculated
average.
Laboratory
QA/
QC
(
Appendix
E)
indicates
the
analytical
results
are
valid
as
reported.

Percent
leached
is
calculated
according
to
the
equation
presented
for
the
TCLP
results,
using
the
leachate
volume
in
Table
5­
6
to
calculate
Liquid/
Solid
ratio.
Values
in
Table
5­
6
indicate
up
to
13
percent
of
the
theoretical
mercury
loading
is
released
to
the
solution
at
pH
2.

Table
5­
6
Constant
pH
Leaching
Results
for
Vendor
B
EEI
Work
Order
01­
12­
039
&
01­
12­
515
pH
Phase
I
Wasteform
Phase
II
Wasteform
Memo
Hg
conc.
(
mg/
L)
Percent
Leached1
Percent
Leached2
Leachate
Volume3
(
mL)
Hg
conc.
(
mg/
L)
Percent
Leached1
Percent
Leached2
Leachate
Volume3
(
mL)

2
46.6
13.3
21.8
507.73
1.92
0.566
1.52
523.26
PI­
5.74
2
44.0
12.7
20.8
511.71
0.617
0.184
0.493
528.15
PII­
103
4
0.126
0.0365
0.0599
514.92
0.137
0.0398
0.107
515.72
6
0.606
0.1808
0.2960
529.53
0.102
0.0304
0.082
529.55
8
0.344
0.0975
0.1597
503.13
0.0873
0.0253
0.068
513.98
PI­
28.9
8
0.460
0.1305
0.2137
503.70
0.0753
0.0216
0.058
508.87
PII­
14.8
10
0.0634
0.0190
0.0311
531.84
0.0577
0.0173
0.046
531.32
12
0.0646
0.0183
0.0299
501.61
0.00885
0.0027
0.007
548.93
PI­
23.7
12
0.0509
0.0175
0.0287
610.82
0.00609
0.0019
0.005
542.26
PII­
36.9
2
<
0.00050
­
­
500.61
<
0.00050
­
­
501.40
Blank
1
Calculated
based
on
the
theoretical
total
mercury
content
of
7,100
mg/
kg
for
the
Phase
I
and
II
waste.
2
Calculated
based
on
the
average
mercury
value
reported
for
the
Phase
I
and
II
waste.
3
Total
volume
of
leachate,
including
addition
of
NaOH
and/
or
HNO
3.
0
.
0
0
1
0
.
0
1
0
.1
1
1
0
1
0
0
1
0
0
0
0
2
4
6
8
1
0
1
2
1
4
P
h
a
s
e
I
P
h
a
s
e
II
U
n
t
re
a
t
e
d
0.025
mg
/
L
0.2
mg
/
L
TCLP
­
P
h
a
s
e
I
TCLP
­
P
h
a
s
e
II
0.001
0.01
0.1
1
10
100
0
2
4
6
8
10
12
14
pH
Percent
(%)
Leached
P
h
a
s
e
I
P
h
a
s
e
II
Figure
5­
5
Constant
pH
Leaching
Results
for
Vendor
B
Concentration
Leached
Figure
5­
6
Constant
pH
Leaching
Results
for
Vendor
B
Percentage
Leached
A
comparison
of
the
results
for
Phase
I
and
Phase
II
(
Figure
5­
5)
shows
that
mercury
concentrations
are
similar
at
pH
4
and
10,
but
the
overall
patterns
are
unique.
Samples
representing
the
Phase
I
material
show
a
sharp
decrease
from
pH
2
to
4
and
then
an
increase
to
pH
6
followed
by
a
decreasing
trend.
For
Phase
II,
the
mercury
concentration
steadily
decreases
as
pH
increases,
with
the
observed
mercury
values
being
about
two
orders
of
magnitude
lower
than
the
untreated
surrogate.

5.4
Vendor
C
Table
5­
7
summarizes
results
for
total
mercury
recovered
from
digested
solids
representing
Batches
1
through
3
and
the
raw
surrogate.
The
reported
standard
deviation
and
CV
for
the
total
mercury
results
are
quite
low,
indicating
a
good
job
in
the
homogenization
of
the
waste
form.
Relative
to
the
dry
weight
basis
of
the
raw
surrogate
(
9862
mg/
kg)
the
surrogate
loading
in
batches
1,
2
and
3
was
44.9%,
47%
and
31.7%.
Therefore,
the
mercury
concentration
in
waste
prepared
by
Vendor
C
varies
form
batch
to
batch
as
follows:
4,430
mg/
kg
(
9862*
0.449),
Batch
1;
4,640
mg/
kg,
Batch
2;
and
3,125
mg/
kg,
Batch
3.
Recovery
of
the
mercury
from
the
waste
is
nearly
identical
for
Batches
1
and
2
and
increases
for
Batch
3.
This
implies
the
digestion
used
to
characterize
the
mercury
loading
of
Batches
1
and
2
is
less
complete
than
that
carried
out
on
the
Batch
3
waste.
In
all
cases,
the
digestion
did
not
recover
the
total
mercury
loading.

The
TCLP
tests
were
performed
only
on
Batch
1
and
2
waste,
and
the
results
show
greater
variability
relative
to
the
standard
deviation
and
CV
for
the
total
mercury
results
on
the
solids.
However,
all
of
the
mercury
concentrations
reported
for
the
TCLP
tests
are
less
than
the
performance
goal
for
the
test
(
0.025
mg/
L).

The
percentage
of
material
that
is
leached
from
the
solids
is
very
low,
and
values
are
calculated
for
the
theoretical
mercury
loading
of
each
batch
and
for
the
average
total
mercury
value
measured
on
the
digested
treated
solids.

Results
for
the
constant
pH
leach
tests
are
tabulated
in
Table
5­
8
and
plotted
on
Figure
5­
7
as
the
concentration
of
mercury
that
leached,
along
with
the
concentration
in
the
TCLP
leachate.
The
constant
pH
leaching
data
are
also
presented
in
Figure
5­
8
as
the
percentage
of
mercury
that
leached.
Table
5­
8
reports
the
analytical
results,
the
amount
of
mercury
removed
from
the
solid
(
percent
leached),
and
the
total
volume
of
leachate,
including
the
total
volume
of
reagents
added
to
maintain
the
indicated
pH.
Duplicates
were
run
at
pH
values
of
2,
8
and
11
and
12.
An
additional
set
of
duplicates
was
run
at
pH
2
in
an
attempt
to
improve
the
RPD,
but
similar
results
were
obtained.
Relative
percent
difference
(
RPD)
for
the
experimental
duplicates
at
pH
8
(
Batch
2
only)
and
pH
12
meet
the
QA
criteria
of
±
50
percent.
The
duplicate
values
appear
with
the
calculated
average
on
Figure
5­
7
and
Figure
5­
8,
and
the
trend
is
drawn
through
the
calculated
average.
Laboratory
QA/
QC
(
Appendix
E)
indicates
the
analytical
results
are
valid
as
reported.
Table
5­
7
Analytical
Results
for
Vendor
C
EEI
Work
Order
01­
08­
371
&
01­
10­
674
Wasteform
TCLP
Sample
Total
Hg
(
mg/
kg)
Percent
Recovery1
Sample
Final
pH
TCLP
(
mg/
L)
Percent
Leached1
Percent
Leached2
Batch
#
1
1
1750
39.5
1
8.67
0.0102
0.00461
0.0109
2
1910
43.1
2
8.62
0.00945
0.00427
0.0101
3
1830
41.3
3
8.81
0.00769
0.00347
0.00824
4
1810
40.9
­
­
­
­
5
2030
45.8
­
­
­
­
Average
1866
42.1
Average
0.00911
0.00412
0.00977
Std.
Dev.
108
­
Std.
Dev.
0.00129
­
­
CV
5.79
­
CV
14.1
­
­
Batch
#
2
1
1800
38.8
1
9.14
0.000860
0.000371
0.000933
2
1850
39.9
2
9.10
0.00133
0.000574
0.00144
3
1930
41.6
3
9.12
0.00186
0.000803
0.00202
4
1970
42.5
­
­
­
­
5
1670
36.0
­
­
­
­
Average
1844
39.8
Average
0.00135
0.000583
0.00146
Std.
Dev.
118
­
Std.
Dev.
0.000500
­
­
CV
6.39
­
CV
37.1
­
­
Batch
#
3
1
2170
69.4
­
6.67
­
­
­
2
2160
69.1
­
6.67
­
­
­
3
2030
65.0
­
6.70
­
­
­
4
2090
66.9
­
6.70
­
­
­
5
2140
68.5
­
­
­
­
Average
2118
67.8
­
­
­
­
Std.
Dev.
58.1
­
­
­
­
­
CV
2.74
­
­
­
­
­
Untreated
Surrogate
1
5790
1163
­
­
­
­
2
5340
1073
­
­
­
­
3
4720
94.43
­
­
­
­
Average
5283
1063
­
­
­
­
Std.
Dev.
537­
­
­­
­
CV
10.2
­
­
­
­
­

1
Calculated
based
on
the
theoretical
total
mercury
content
of
4,430,
4,640
and
3,125mg/
kg
for
treated
waste
in
Batches
1,
2
and
3,
respectively.
2
Calculated
based
on
the
average
mercury
value
reported
for
Batches
1,
2
and
3.
3
Calculated
based
on
the
theoretical
mercury
content
of
5,000
mg/
kg
for
the
surrogate.
0
.
0
0
1
0
.
0
1
0
.1
1
1
0
1
0
0
1
0
0
0
0
2
4
6
8
1
0
1
2
1
4
pH
Hg
Concentration
(
mg/
L)

B
a
t
c
h
#
1
B
a
t
c
h
#
2
U
n
t
r
e
a
t
e
d
0.025
mg
/
L
0.2
mg
/
L
T
C
L
P
­
B
a
t
c
h
1
T
C
L
P
­
B
a
t
c
h
2
Table
5­
8
Constant
pH
Leaching
Results
for
Vendor
C
EEI
Work
Order
01­
08­
371
&
01­
10­
360
pH
Batch
#
1
Batch
#
2
Memo
Hg
conc.
(
mg/
L)
Percent
Leached1
Percent
Leached2
Leachate
Volume3
(
mL)
Hg
conc.
(
mg/
L)
Percent
Leached1
Percent
Leached2
Leachate
Volume3
(
mL)

2
0.356
0.164
0.389
509.94
4.39
1.97
4.96
520.87
B1­
190
2
13.9
6.28
14.9
500.39
1.11
0.538
1.35
561.92
B2­
119
4
0.00816
0.00377
0.0089
510.98
0.0340
0.0158
0.0397
538.41
­

6
0.0441
0.0199
0.0653
690.76
0.118
0.0612
0.154
601.24
­

8
0.0391
0.0177
0.0426
508.74
0.0106
0.00595
0.0149
649.94
B1­
62.0
8
0.0206
0.00951
0.0226
511.09
0.00797
0.00444
0.0111
644.78
B2­
28.3
10
0.0108
0.00497
0.0118
509.48
0.00337
0.00149
0.0037
512.46
­

12
0.0353
0.0170
0.0404
533.58
0.00239
0.00110
0.00279
538.25
B1­
4.93
12
0.0336
0.01838
0.0436
605.71
0.00264
0.00125
0.00313
547.55
B2­
9.94
2
<
0.00050
­
­
500.58
<
0.00050
­
­
500.80
Blank
2
14.9
7.11
16.9
527.64
­
­
­
­
RB1­
188
2
0.478
0.217
0.514
501.98
­
­
­
­
­

1
Calculated
based
on
the
theoretical
total
mercury
content
of
4,430,
and
4,640
mg/
kg
for
treated
waste
in
Batches
1
and
2,
respectively.
2
Calculated
based
on
the
average
mercury
value
reported
for
Batches
1
and
2.
3
Total
volume
of
leachate,
including
addition
of
NaOH
and/
or
HNO
3.

Figure
5­
7
Constant
pH
Leaching
Results
for
Vendor
C
Concentration
Leached
0.001
0.01
0.1
1
10
100
0
2
4
6
8
10
12
14
pH
Percent
(%)
Leached
B
a
t
c
h
1
B
a
t
c
h
2
Figure
5­
8
Constant
pH
Leaching
Results
for
Vendor
C
Percentage
Leached
Percent
leached
is
calculated
according
to
the
equation
presented
previously,
using
the
leachate
volume
in
Table
5­
8
to
calculate
Liquid/
Solid
ratio.
Values
in
Table
5­
8
indicate
up
to
7
percent
of
the
theoretical
mercury
loading
is
released
to
the
Batch
1
solutions
at
pH
2.

Figure
5­
7
compares
the
results
for
Batches
1
and
2
and
the
ALTER
untreated
surrogate.
The
plotted
mercury
concentrations
produce
similar
patterns
for
each
batch,
with
the
exception
of
the
points
at
pH
12.
Samples
representing
Batch
1
material
show
an
increase
at
pH
12,
relative
to
a
decrease
for
Batch
2.
The
minimum
mercury
concentration
is
observed
at
pH
4
for
Batch
1
and
pH
12
for
Batch
2.
The
observed
mercury
values
are
two
to
three
orders
of
magnitude
lower
than
the
untreated
surrogate.

5.5
Vendor
D
Table
5­
9
summarizes
results
for
total
mercury
recovered
from
digested
solids
representing
treated
material
from
Batches
1
and
2
and
the
raw
surrogate.
The
reported
standard
deviation
and
CV
for
the
total
mercury
results
indicate
moderate
variation
in
the
mercury
recovered
from
the
waste
forms.
Relative
to
the
dry
weight
basis
in
the
untreated
surrogate
(
9862
mg
Hg/
kg
of
dry
weight),
the
surrogate
loading
for
batches
1
and
2
was
25.4%
by
dry
weight.
Therefore,
the
mercury
concentration
in
waste
prepared
by
Vendor
D
is
2,500
mg/
kg
(
9862*.
254).
Recovery
of
the
mercury
from
the
waste
is
similar
for
Batches
1
and
2,
but
none
of
the
digestions
recovered
the
total
mercury
loading.

The
TCLP
results
show
greater
variability
relative
to
the
standard
deviation
and
CV
for
the
total
mercury
results
on
the
solids.
However,
all
of
the
mercury
concentrations
reported
for
the
TCLP
tests
are
less
than
performance
goal
for
the
test
(
0.025
mg/
L),
with
the
exception
of
Sample
1
in
Batch
2.
Table
5­
9
Analytical
Results
for
Vendor
D
EEI
Work
Order
01­
09­
416
Wasteform
TCLP
Sample
Total
Hg
(
mg/
kg)
Percent
Recovery
Sample
Final
pH
TCLP
(
mg/
L)
Percent
Leached1
Percent
Leached2
Batch
#
1
1
1210
48.4
1
10.64
0.00539
0.00431
0.00718
2
1530
61.2
2
10.59
0.00785
0.00628
0.0105
3
1280
51.2
3
10.59
0.00476
0.00381
0.00634
4
1630
65.2
4
10.59
0.00473
0.00378
0.00630
5
1860
74.4
­
­
­
­

Average
1502
60.1
Average
0.00568
0.00455
0.00757
Std.
Dev.
265
­
Std.
Dev.
0.00148
­
­

CV
17.6
­
CV
26.0
­
­

Batch
#
2
1
1230
49.2
1
9.14
0.0768
0.0614
0.111
2
1160
46.4
2
9.10
0.0119
0.00952
0.0173
3
1700
68.0
3
9.12
0.0578
0.0462
0.0839
4
1400
56.0
­
­
­
­

5
1400
56.0
­
­
­
­

Average
1378
55.1
Average
0.0488
0.0391
0.0709
Std.
Dev.
209
­
Std.
Dev.
0.0334
­
­

CV
15.1
­
CV
68.3
­
­

Untreated
Surrogate
1
3380
67.6
­
­
­
­

2
3830
76.6
­
­
­
­

3
3910
78.2
­
­
­
­

Average
3707
74.1
­
­
­
­

Std.
Dev.
286
­
­
­
­
­

CV
7.71
­
­
­
­
­

1
Calculated
based
on
the
theoretical
total
mercury
content
of
2,500
mg/
kg
for
waste
in
Batches
1
and
2.
2
Calculated
based
on
the
average
mercury
value
reported
for
Batches
1
and
2.
3
Calculated
based
on
the
theoretical
mercury
content
of
5,000
mg/
kg
for
the
surrogate.
The
percentage
of
material
that
is
leached
from
the
solids
is
very
low,
and
values
are
calculated
for
the
theoretical
mercury
loading
of
each
batch
and
for
the
average
total
mercury
value
measured
on
the
digested
treated
solids.

Results
for
the
constant
pH
leach
tests
are
tabulated
in
Table
5­
10
and
plotted
on
Figure
5­
9
as
the
concentration
of
mercury
that
leached,
along
with
the
concentration
in
the
TCLP
leachate.
The
constant
pH
leaching
data
are
also
presented
in
Figure
5­
10
as
the
percentage
of
mercury
that
leached..
Table
5­
10
reports
the
analytical
results,
the
amount
of
mercury
removed
from
the
solid
(
percent
leached),
and
the
total
volume
of
leachate,
including
the
total
volume
of
reagents
added
to
maintain
the
indicated
pH.
Duplicates
were
run
at
pH
values
of
2,
8
and
11
and
12.
Relative
percent
difference
(
RPD)
for
the
experimental
duplicates
meet
the
QA
criteria
of
±
50
percent,
with
the
exception
of
the
Batch
2
sample/
duplicate
at
pH
2.
The
duplicate
values
appear
with
the
calculated
average
on
Figure
5­
9
and
Figure
5­
10,
and
the
trend
is
drawn
through
the
calculated
average.
Laboratory
QA/
QC
(
Appendix
E)
indicates
the
analytical
results
are
valid
as
reported.

Table
5­
10
Constant
pH
Leaching
Results
for
Vendor
D
EEI
Work
Order
01­
09­
416
pH
Batch
#
1
Batch
#
2
RPD
Sample
Dups.
Hg
conc.
(
mg/
L)
Percent
Leached1
Percent
Leached2
Leachate
Volume3
(
mL)
Hg
conc.
(
mg/
L)
Percent
Leached1
Percent
Leached2
Leachate
Volume3
(
mL)

2
0.127
0.1066
0.1777
525.45
0.257
0.2348
0.427
572.06
B1­
48.4
2
0.0775
0.0650
0.108
525.23
0.130
0.110
0.200
520.08
B2­
65.6
4
2.63
2.61
4.35
621.42
4.35
3.67
6.67
518.48
6
0.240
0.230
0.384
601.01
0.289
0.269
0.490
584.10
8
0.0603
0.056
0.0937
583.34
0.0724
0.065
0.117
558.47
B1­
1.50
8
0.0594
0.056
0.0937
592.18
0.0658
0.062
0.113
591.10
B2­
9.55
10
2.17
2.16
3.60
622.85
0.0204
0.017
0.031
521.27
12
0.0156
0.0125
0.0209
502.81
0.0250
0.020
0.037
505.47
B1­
35.5
12
0.0109
0.0088
0.0146
503.07
0.0193
0.015
0.028
501.11
B2­
43.0
2
0.00052
­
­
500.69
<
0.00050
­
­
500.51
Blank
1
Calculated
based
on
the
theoretical
total
mercury
content
of
2,500
mg/
kg
for
waste
in
Batches
1
and
2.
2
Calculated
based
on
the
average
mercury
value
reported
for
Batches
1
and
2.
3
Total
volume
of
leachate,
including
addition
of
NaOH
and/
or
HNO
3.
0.001
0
.
0
1
0
.
1
1
10
100
1000
0
2
4
6
8
10
12
14
pH
Hg
Concentration
(
mg/
L)

B
a
t
c
h
#
1
B
a
t
c
h
#
2
U
n
t
re
a
t
e
d
0.025
mg
/
L
0.2
mg
/
L
T
C
L
P
­
B
a
t
c
h
1
T
C
L
P
­
B
a
t
c
h
2
0.001
0.01
0.1
1
10
0
2
4
6
8
10
12
14
pH
Percent
(%)
Leached
Batch
1
Batch
2
Figure
5­
9
Constant
pH
Leaching
Results
for
Vendor
D
Concentration
Leached
Figure
5­
10
Constant
pH
Leaching
Results
for
Vendor
D
Percentage
Leached
3
F.
Sanchez,
D.
S.
Kosson,
C.
H.
Mattus,
and
M.
I.
Morris,
Use
of
a
New
Leaching
Test
Framework
for
Evaluating
Alternative
Treatment
Processes
for
Mercury
Contaminated
Mixed
Waste
(
Hazardous
and
Radioactive);
http://
www.
cee.
vanderbilt.
edu/
cee/
research_
projects.
html
Percent
leached
is
calculated
according
to
the
equation
presented
previously,
using
the
leachate
volume
in
Table
5­
10
to
calculate
Liquid/
Solid
ratio.
Values
in
Table
5­
10
indicate
up
to
4
percent
of
the
theoretical
mercury
loading
is
released
to
the
Batch
2
solution
at
pH
4.

Figure
5­
9
compares
the
results
for
Batches
1
and
2
and
the
untreated
surrogate.
The
plotted
mercury
concentrations
produce
strikingly
similar
patterns
for
each
batch,
with
the
exception
of
the
Batch
1
point
at
pH
10.
Although
the
laboratory
QA/
QC
check
corroborates
the
reported
value,
it
is
highly
suspect
given
the
excellent
agreement
of
the
other
samples.
However,
similar
variability
was
also
observed
in
the
region
of
pH
10­
13
in
a
prior
study
of
soil
treated
by
this
process.
3
The
overall
trend
is
an
increase
from
pH
2
to
4
and
a
smooth
decrease
from
pH
4
to
pH
12.
The
minimum
mercury
concentrations
are
observed
at
pH
12,
and
values
are
one
to
three
orders
of
magnitude
lower
than
the
untreated
surrogate.
0.001
0.01
0.1
1
10
100
1000
0
2
4
6
8
10
12
14
pH
Hg
Concentration
(
mg/
L)
Vendor
A
Pellets
Vendor
A
Crushed
Untreated
0.025
mg/
L
0.2
mg/
L
Vendor
B
Phase
I
Vendor
B
Phase
II
Vendor
C
Batch
1
Vendor
C
Batch
2
Vendor
D
Batch
1
Vendor
D
Batch
2
5.6
Conclusions
Figure
5­
11
provides
the
constant
pH
leach
test
data
discussed
previously
for
all
three
vendors,
plotted
on
a
concentration
basis.
From
this
Figure,
it
is
evident
that
the
stability
of
the
mercury
in
the
treated
waste
forms
varies
widely
across
the
pH
range
tested.
For
example,
Vendor
A's
treated
waste
form
performed
better
at
pH
2
and
10­
11,
than
at
the
other
pHs
tested.
Vendor
B's
treated
waste
form
performed
best
at
low
pH,
while
Vendor
C's
waste
form
leached
less
mercury
at
high
pH
than
at
low
pH.
Clearly,
the
stability
of
mercury
in
these
treated
waste
forms
will
be
highly
dependant
on
the
disposal
conditions.
The
combination
of
site­
specific
disposal
conditions
and
appropriate
treatment
technology
must
be
considered
as
decisions
are
made
about
disposal
of
waste
mercury.

Figure
5­
11
Constant
pH
Leaching
Results
for
All
Vendors
Concentration
Leached
5.7
Additional
Information
Resources
The
following
articles
are
relevant
to
this
topic:

"
Stabilization/
solidification
(
S/
S)
of
mercury­
containing
wastes
using
reactivated
carbon
and
Portland
cement",
Zhang,
Jian;
Bishop,
Paul
L.
Journal
of
Hazardous
Materials
(
2002),
92(
2),
199­
212.

"
Sulfide­
induced
stabilization
and
leachability
studies
of
mercury
containing
wastes",
Piao,
Haishan;
Bishop,
Paul,
Abstracts
of
Papers,
223rd
ACS
National
Meeting,
Orlando,
FL,
United
States,
April
7­
11,
2002
(
2002),
ENVR­
207.

"
Phosphate­
induced
mercury
stabilization",
Zhang,
Jian;
Bishop,
Paul
L.,
Preprints
of
Extended
Abstracts
presented
at
the
ACS
National
Meeting,
American
Chemical
Society,
Division
of
Environmental
Chemistry
(
2001),
41(
1),
422­
424.

"
Sulfide­
induced
mercury
stabilization",
Piao,
Haishan;
Bishop,
Paul
L.,
Preprints
of
Extended
Abstracts
presented
at
the
ACS
National
Meeting,
American
Chemical
Society,
Division
of
Environmental
Chemistry
(
2001),
41(
1),
428­
431.

"
Stabilization
of
radioactively
contaminated
elemental
mercury
wastes",
Stewart,
Robin;
Broderick,
Tom;
Litz,
John;
Brown,
Cliff;
Faucette,
Andrea.,
Proceedings
of
the
International
Conference
on
Decommissioning
and
Decontamination
and
on
Nuclear
and
Hazardous
Waste
Management,
Denver,
Sept.
13­
18,
1998
(
1998),
3
33­
36.

"
Mercury
stabilization
in
chemically
bonded
phosphate
ceramics",
Wagh,
Arun
S.;
Jeong,
Seung­
Young;
Singh,
Dileep,
Ceramic
Transactions
(
1998),
87(
Environmental
Issues
and
Waste
Management
Technologies
in
the
Ceramic
and
Nuclear
Industries
III),
63­
73.

"
A
Framework
for
Risk
Assessment
of
Disposal
of
Wastes
Treated
by
Solidification/
Stabilization",
Batchelor,
B.,
Environmental
Engineering
Science,
14(
1):
3­
13,
1997.

"
A
study
of
immobilization
of
four
heavy
metals
by
solidification/
stabilizatioin
with
Portland
cement",
Susan
A.
Trussell,
Ph.
D.
Dissertation,
Texas
A&
M
Univeristy,
College
Station,
Texas,
1994.

"
Immobilization
of
chromium
and
mercury
from
industrial
wastes",
Wasay,
S.
A.;
Das,
H.
A.
,
J.
Environ.
Sci.
Health,
Part
A
(
1993),
A28(
2),
285­
97.

Chemical
Fixation
and
Solidification
of
Hazardous
Wastes,
Jesse
R.
Conner,
Van
Nostrand
Reinhold,
New
York,
1990.
"
An
investigation
of
mercury
solidification
and
stabilization
in
portland
cement
using
x­
ray
photoelectron
spectroscopy
and
energy
dispersive
spectroscopy",
McWhinney,
Hylton
G.;
Cocke,
David
L.;
Balke,
Karl;
Ortego,
J.
Dale.,
Cem.
Concr.
Res.
(
1990),
20(
1),
79­
91.

"
Studies
of
zinc,
cadmium
and
mercury
stabilization
in
OPC/
PFA
mixtures",
Poon,
C.
S.;
Perry,
R.,
Mater.
Res.
Soc.
Symp.
Proc.
(
1987),
86(
Fly
Ash
Coal
Convers.
By­
Prod.),
67­
76.

"
Permeability
study
on
the
cement
based
solidification
process
for
the
disposal
of
hazardous
wastes",
Poon,
C.
S.;
Clark,
A.
I.;
Perry,
R.;
Barker,
A.
P.;
Barnes,
P.,
Cem.
Concr.
Res.
(
1986),
16(
2),
161­
72.

"
Mechanisms
of
metal
fixation
and
leaching
by
cement
based
fixation
processes",
Poon,
C.
S.;
Clark,
A.
I.;
Peters,
C.
J.;
Perry,
R.,
Waste
Manage.
Res.
(
1985),
3(
2),
127­
42.

"
Mechanisms
of
metal
stabilization
by
cement
based
fixation
processes",
Poon,
C.
S.;
Peters,
C.
J.;
Perry,
R.;
Barnes,
P.;
Barker,
A.
P.,
Sci.
Total
Environ.
(
1985),
41(
1),
55­
71.
