2.
Response
to
Comments
2.9
Individual
Responses
to
Comments
from
Organizations
Draft
EIR
Tables
4.2
and
4.3
list
the
maximum
concentration
of
the
constituents
detected
in
groundwater
and
compares
these
concentrations
to
a
regulatory
threshold,
in
this
instance
the
Maximum
Contaminant
Level
(MCL),
if
the
MCL
is
available,
i.e.,
developed
by
the
USEPA
and/or
the
State
of
California
Environmental
Protection
Agency,
pursuant
to
standard
practice.
See
for
discussion
of
risk-
based
health
standards
to
be
set
by
the
RWQCB
and
DTSC.
As
discussed
in
that
Master
Response,
human
health
risk
assessments
will
be
required
to
determine
remediation
goals
for
the
specific
constituents
of
concern
within
the
Baylands,
based
on
the
land
uses
determined
by
the
City
of
Brisbane
to
be
appropriate
within
the
Baylands.
See
for
discussion
of
cumulative
effects
of
multiple
toxins.
The
existing
landfill
gas
control
system
was
inspected
by
SCS
in
2008
and
found
to
require
repairs
even
though
it
was
operating
correctly.
The
existing
landfill
gas
control
system
flare
station
is
monitored
weekly,
the
landfill
gas
extraction
wells
are
monitored
monthly,
and
the
emissions
components
are
monitored
quarterly.
As
part
of
its
requirements
for
Title
27
landfill
closure,
the
RWQCB
will
review
the
adequacy
of
the
existing
landfill
gas
control
system
to
collect
and
combust
methane
and
other
landfill
gases
pursuant
to
Title
27
standards.
Based
on
that
determination,
the
RWQCB
will
set
specific
requirements
for
needed
upgrades,
expansions,
or
replacement
of
the
existing
landfill
gas
control
system.
Because
methane
can
move
underground
in
multiple
directions
that
may
change
over
time,
determining
the
specific
locations
where
methane
was
detected
in
the
past
is
not
relevant
to
the
analysis
or
conclusions
of
the
Draft
EIR.
Methane
is
generated
as
the
organic
matter
in
the
landfill
decomposes
and
as
the
organic
material
in
the
tidal
flats
on
which
the
waste
was
placed
decomposes.
The
rate
of
methane
generation
has
been
documented
to
have
slowed
during
the
methane
gas
monitoring
conducted
as
part
of
the
landfill
gas
control
system.
As
methane
is
a
product
of
decomposition
and
as
it
seeks
the
path
of
least
resistance,
it
could
be
detected
at
any
place
within
the
landfill.
The
Draft
EIR
does
not
state
or
imply
that
the
current
collection
system
will
be
adequate
for
long-term
use
following
Title
27
closure
of
the
landfill.
See
Brisbane
Baylands
Final
EIR
2.9.1-47
May
2015