Peer
Review
Comments
on:

Technical
Background
Document:
Mercury
Wastes
Evaluation
of
Treatment
of
Bulk
Elemental
Mercury
and
Technical
Background
Document:
Mercury
Wastes
Evaluation
of
Treatment
of
Mercury
Surrogate
Waste
July
2,
2002
Submitted
by:

Bart
Simmons,
Ph.
D.
Hazardous
Materials
Laboratory
Department
of
Toxic
Substances
Control
2151
Berkeley
Way,
Room
515
Berkeley,
CA
94704
Submitted
to:

Science
Applications
International
Corporation
Engineering
and
Environmental
Management
Group
11251
Roger
Bacon
Drive
Reston,
Virginia
20190
and
U.
S.
Environmental
Protection
Agency
Ariel
Rios
Building
Office
of
Solid
Waste
1200
Pennsylvania
Avenue,
N.
W.
Washington,
D.
C.
20460
EPA
Contract
No.
68­
W0­
0122
Work
Assignment
No.
0­
2
SAIC
Project
No.
06­
0758­
08­
4042­
000
"
Evaluation
of
Mercury
Surrogate
Waste"

1.
Was
the
experimental
design
of
the
study
appropriate?

The
design
did
not
follow
the
Data
Quality
Objectives
process,
nor
a
similar
planning
process.
As
a
result,
there
is
little
relationship
between
the
objectives
and
the
design.
A
RCRA
disposal
scenario
was
implied,
but
the
pH
range
did
not
extend
to
pH
12.5,
and
data
show,
e.
g.,
Figure
5.3,
that
major
changes
occur
in
extraction
at
high
pH.

The
QAPP
for
this
study
was
also
included
in
the
electronic
file
for
the
evaluation
of
bulk
elemental
mercury.
A
statement
of
accreditation
for
the
labs
could
have
been
substituted
for
much
of
the
generic
material
in
the
QAPP.

2.
Was
the
study
conducted
properly?

The
appropriate
procedures
were
used,
and
the
study
appears
to
have
been
done
as
planned.

3.
Were
the
stated
objectives
adequately
met?

The
first
objective
in
the
peer
review
charge
was
to
evaluate
alternative
treatment
technologies
to
obtain
a
goal
of
0.025
mg/
L
Hg
over
a
range
of
pH
2
to
pH
12.
This
objective
was
adequately
met
with
the
exception
of
an
apparent
sample
heterogeneity
problem.

The
second
objective
was
to
compare
constant
pH
protocol
results
to
standard
TCLP
results.
This
was
adequate
with
the
exception
of
the
apparent
sample
heterogeneity.

General
Questions
1.
Are
you
aware
of
any
other
data/
studies
that
are
relevant
to
the
assessment
of
stabilized
mercury­
bearing
wastes
and
the
behavior
of
these
wastes
in
the
environment?

This
report
does
not
have
a
list
of
baseline
references,
so
the
question
is
very
broad.
A
start
would
be
the
studies
completed
for
EPA
or
used
by
EPA
in
previous
rule­
making.
Second
would
be
a
literature
review
using
appropriate
keywords
2.
With
regard
to
the
disposal
of
treated
mercury
wastes,
are
additional
studies
warranted
for
other
factors
that
impact
solubility
(
e.
g.,
liquid/
solid
ratio,
redox
conditions,
leachate
composition)
or
affect
ability
to
leach,
such
as
use
of
macroencapsulation?
If
you
believe
that
additional
studies
are
needed,
please
explain
why.
An
additional
study
is
needed
to
supplement
this
report,
particularly
extractions
up
to
at
least
pH
12.5.
If
the
mercuric
selenide
process
is
considered
a
viable
technology,
then
mercuric
selenide­
containing
waste
should
be
evaluated
over
the
range
of
pH
2­
12.5
and
with
varied
chloride
content
in
the
leachate.
Additional
studies
on
other
factors
could
be
done,
but
the
priorities
seem
to
be:
pH
effects
(
2­
12.5),
leachate
composition
(
e.
g.,
chloride)
effects,
and
redox
effects.
A
decision
should
be
made
about
how
accurately
a
waste
treatment
evaluation
needs
to
be,
then
deciding
on
the
relative
importance
of
variables.

3.
Do
you
agree
that
the
following
statements
are
supported
by
the
research
results?

a)
Site­
specific
disposal
conditions
must
be
considered
along
with
appropriate
treatment
technology
as
decisions
are
made
about
disposal
of
mercury
wastes.

No.
The
study
provides
useful
data
on
pH
effects,
but
it
does
not
provide
adequate
data
to
support
an
absolute
requirement
for
site­
specific
data.
An
alternative
to
using
site­
specific
conditions
is
a
robust
treatment
standard
which
addresses
the
most
important
variables.
A
major
implementation
problem
with
requiring
site­
specific
conditions
is
the
regulatory
feasibility
of
using
site­
specific
information.
For
any
disposal
of
hazardous
wastes,
treated
or
untreated,
it
is
scientifically
preferable
to
use
site­
specific
conditions
as
well
as
the
waste
properties.
It
is
not
obvious
that
using
site­
specific
data
would
be
better
than
non­
site
specific
approaches
to
meet
the
public
health
and
environmental
protection
goals,
in
part
because
those
specific
goals
are
not
stated
in
this
report.

b)
The
presence
of
chloride
ions
in
a
given
disposal
environment
may
significantly
impact
the
release
from
a
treated
waste
form
(
mercury
selenide)

This
is
discussed
in
the
elemental
mercury
review.

Any
additional
comments?

Table
3­
1
presumably
shows
target
concentrations
and
not
actual
measured
concentrations.

Section
3.3.1
lists
the
worker
protection
standard
as
0.05
g/
m3,
but
Section
lists
the
TLV
as
0.025
mg/
m3.

The
conclusions
in
Section
5.6
refer
to
"...
waste
bulk
elemental
mercury..."
although
this
study
included
several
forms
of
mercury.
"
Evaluation
of
Treatment
of
Bulk
Elemental
Mercury"

1.
Was
the
experimental
design
of
the
study
appropriate?

The
design
followed
neither
EPA
guidance
nor
requirements
for
the
use
of
Data
Quality
Objectives.
I
could
not
find
the
QAPP
for
this
project
(
the
included
QAPP
appeared
identical
to
the
QAPP
for
the
surrogate
sludge
project),
but
it
apparently
dealt
with
only
laboratory
QA/
QC
and
not
the
larger
issues
of
decisions
to
be
made,
decision
error,
and
optimizing
the
plan.
Had
this
been
done,
the
problems
of
treated
waste
inhomogeneity,
sub­
sampling,
numbers
of
samples,
and
optimizing
data
collection,
e.
g.,
using
composite
samples,
could
have
been
incorporated
into
the
study
design.
In
particular,
a
clear
statement
of
the
decisions
could
have
noted
the
importance
of
leaching
solids
up
to
at
least
pH
12.5,
the
regulatory
limit
for
hazardous
waste.
Perhaps
more
important,
a
statement
of
acceptable
errors
should
have
been
included,
e.
g.,
a
treatment
technology
must
be
effective
on
90%
of
wastes
with
a
90%
confidence.
Without
such
a
statement,
it
is
difficult
to
decide
when
a
technology
is
good
enough.

The
design
of
leaching
waste
treated
with
mercuric
selenide
was
not
consistent
with
the
other
leaching
tests
and
only
included
leaching
at
two
pHs.
As
a
result,
the
conclusion
regarding
the
effect
of
chloride
could
not
be
compared
with
the
effect
of
pH
over
a
larger
range.

2.
Was
the
study
conducted
properly?

The
lab
procedures
appear
acceptable,
although
I
could
not
find
detailed
sampling
and
sub­
sampling
procedures.
The
procedures
appear
to
have
been
carried
out
correctly.

3.
Were
the
stated
objectives
adequately
met?

The
first
review
objective
was
to
"
evaluate
the
effectiveness
of
alternative
treatments
to
obtain
a
goal
of
0.025
mg/
L
TCLP
over
a
range
of
pH
2
to
pH
12."
I
assume
the
reference
to
TCLP
is
a
mistake,
and
the
objective
is
to
review
the
results
of
the
constant
pH
extraction.
With
this
assumption,
the
data
collected
were
adequate
to
do
the
evaluation,
with
the
exception
of
an
apparent
sample
heterogeneity
problem.

The
second
review
objective
was
to
compare
constant
pH
protocol
results
to
standard
TCLP
results.
The
data
were
adequate
for
this
comparison,
with
the
exception
of
sample
heterogeneity.

The
third
review
objective
was
to
evaluate
the
effects
of
increased
chloride
concentration
of
mercuric
selenide
at
constant
pH
conditions.
These
data
were
not
adequate
since
only
two
pHs
and
two
chloride
concentrations
were
used;
the
results
were
inadequate
to
quantitatively
compare
the
chloride
effect
with
the
pH
effect.

General
Questions
1.
Are
you
aware
of
any
other
data/
studies
that
are
relevant
to
the
assessment
of
stabilized
mercury­
bearing
wastes
and
the
behavior
of
these
wastes
in
the
environment?

This
report
does
not
have
a
list
of
references,
so
the
question
is
very
broad.
A
start
would
be
the
studies
for
EPA
or
used
by
EPA
in
previous
rule­
making.
Second
would
be
a
literature
review
using
appropriate
keywords.

2.
With
regard
to
the
disposal
of
treated
mercury
wastes,
are
additional
studies
warranted
for
other
factors
that
impact
solubility
(
e.
g.,
liquid/
solid
ratio,
redox
conditions,
leachate
composition)
or
affect
ability
to
leach,
such
as
use
of
macroencapsulation?
If
you
believe
that
additional
studies
are
needed,
please
explain
why.

An
additional
study
is
needed
to
fill
the
holes
in
this
report,
particularly
extractions
up
to
at
least
pH
12.5.
If
the
mercuric
selenide
process
is
considered
a
viable
technology,
then
mercuric
selenide
waste
should
be
evaluated
over
the
range
of
pH
2­
12.5
and
with
varied
chloride
content
in
the
leachate.
Additional
studies
on
other
factors
could
be
done,
but
the
priorities
seem
to
be:
pH
effects
(
2­
12.5),
chloride
effects,
and
redox
effects.

3.
Do
you
agree
that
the
following
statements
are
supported
by
the
research
results?

a)
Site­
specific
disposal
conditions
must
be
considered
along
with
appropriate
treatment
technology
as
decisions
are
made
about
disposal
of
mercury
wastes.

No.
The
study
provides
useful
data
on
pH
and
chlorides,
but
it
does
not
provide
adequate
support
for
an
absolute
requirement
for
site­
specific
data.
An
alternative
to
using
site­
specific
conditions
is
a
robust
treatment
standard
which
addresses
the
most
important
variables.
A
major
implementation
problem
with
requiring
site­
specific
conditions
is
the
regulatory
feasibility
of
using
site­
specific
information.
For
any
disposal
of
hazardous
wastes,
treated
or
untreated,
it
is
scientifically
preferable
to
use
site­
specific
conditions
as
well
as
the
waste
properties.
It
is
misleading,
however,
to
pursue
this
path
unless
the
regulatory
system
has
the
flexibility
to
implement
efficiently
to
provide
the
necessary
protection
to
public
health
and
the
environment.
b)
The
presence
of
chloride
ions
in
a
given
disposal
environment
may
significantly
impact
the
release
from
a
treated
waste
form
(
mercury
selenide)

Yes,
the
data
in
the
report
do
support
this
statement.
However,
there
is
no
comparison
with
other
variables,
not
even
an
adequate
comparison
with
pH,
which
shows
the
relative
importance
of
chloride
concentration.

Any
additional
comments?

Some
minor
editing
was
needed
for
the
final
reports,
i.
e.,
spaces
and
placement
of
hyphens.

Data
on
the
quantities
of
listed
wastes
would
have
been
useful
to
understand
the
magnitude
of
various
waste
treatment
problems.
