2.
Response
to
Comments
2.9
Individual
Responses
to
Comments
from
Organizations
Landfill
gas
is
about
40-60%
methane,
with
the
remainder
being
mostly
carbon
dioxide
(CO2).
Landfill
gas
also
contains
varying
amounts
of
nitrogen,
oxygen,
water
vapor
,
sulfur,
and
other
“non
-
methane
organic
compounds.”
There
is
limited
data
comparing
emissions
from
landfill
gas
flares
to
energy
producing
combustion
devices
(which
includes
boilers,
turbines
and
internal
combustion
engines).
According
to
very
limited
data
in
a
1995
EPA
report,
carbon
monoxide
and
NO
x
emissions
are
highest
from
internal
combustion
engines
and
lowest
from
boilers.
Flares
and
gas
turbines
are
in
the
middle.
11
Once
collected,
landfill
gas
“disposal”
is
typically
focused
around
handling
the
methane
(usually
by
burning).
To
address
toxics
issues,
landfill
gas
can
be
filtered
so
that
the
halogenated
compounds
are
segregated.
Once
filtered
out,
these
compounds
would
not
be
combusted,
but
be
handled
as
hazardous
waste
and
isolated
from
the
environment
as
best
as
is
possible
until
there
is
a
proven
technology
which
can
neutralize
the
toxics
by
converting
the
halogens
to
relatively
harmless
chemicals
like
salts.
When
conducting
investigations
for
contaminated
sites,
the
focus
is
on
identifying
constituents
of
concern
in
the
media,
along
with
their
concentrations.
Because
the
responsible
party
(landowner)
must
provide
for
site
remediation
regardless
of
past
users
of
the
site,
comprehensively
identifying
those
past
users
is
unnecessary.
The
figures
referenced
in
this
comment
do,
in
fact,
pertain
to
and
and
show
contamination
in
relation
to
land
uses
proposed
throughout
the
site.
Maps
of
the
former
landfill
area
are
included
in
the
Draft
EIR
as
Figures
4.G-2a
through
4.G-4.
Figure
4.G-6m
is
intended
to
show
current
TCE
concentrations
and
does
not
purport
to
address
the
issues
raised
in
the
comment.
Current
concentrations
of
other
chemicals
of
concern
are
shown
in
Figures
4.G-6a
(volatile
organic
compounds),
4.G-6b
(chlorinated
ethenes),
4.G-6c
(arsenic),
4.G-6d
(cadmium),
4.G-6e
(lead),
4.G-6f
(mercury),
4.G-6g
(PCBs),
4.G-6h
(bunker
C
oil),
4.G-6i
(tetrachloroethene),
4.G-6j
(trichloroethene),
4.G-6k
(dichloroethene),
and
4.G-6l
(vinyl
chloride
[historic
maximum
concentrations]).
The
comment
is
correct
that
the
testing
referred
to
on
page
4.G-47
was
conducted
pursuant
to
DTSC
requirements.
As
discussed
regulatory
authority
for
remediation
and
landfill
testing
lies
with
the
RWQCB
and
DTSC,
rather
than
the
City.
Pursuant
to
their
regulatory
authority,
the
RWQCB
and
11
Methodologies
for
Quantifying
Pollution
Prevention
Benefits
from
Landfill
Gas
Control
and
Utilization,"
EPA
document
#600SR95089,
July
1995
Brisbane
Baylands
Final
EIR
2.9.1-48
May
2015