2.
Response
to
Comments
2.9
Individual
Responses
to
Comments
from
Organizations
for
dispersion
modeling,
the
HRA
analysis
of
the
Draft
EIR
is
consistent
with
the
latest
methodology
of
the
State
of
California.
The
comment
is
correct
that
there
were
12
Spare
the
Air
Days
in
December
of
2013,
an
increase
from
what
occurred
in
December
2012.
During
the
last
winter
Spare
the
Air
Season,
from
November
2013
through
February
2014,
there
were
a
total
of
30
Spare
the
Air
Days.
This
is
the
most
since
the
2006-2007
season
when
there
were
also
30
Spare
the
Air
Days
3
.
This
number
of
Spare
the
Air
alerts
is
thus
not
unprecedented.
The
HRA
analysis
of
the
Draft
EIR,
summarized
in
Impacts
4.B-3
and
4.B-5
and
contained
in
the
Appendix
D,
used
meteorological
data
that
included
the
2006-2007
season.
Therefore,
the
health
risk
assessment
included
a
worst-case
meteorological
year
and
represented
a
conservative
analysis.
Applying
this
conservative
meteorological
assumption,
localized
health
risk
impacts
were
identified
in
Impact
4.B-3
and
Impact
4.B-5
as
less
than
significant
in
the
Draft
EIR.
Anaerobic
digestion,
if
ultimately
approved
for
the
Recology
facility,
would
be
contained
within
an
enclosed
vessel
and
the
process
itself
is
not
a
source
of
criteria
or
toxic
air
pollutants.
Consequently,
there
would
have
no
impact
on
air
quality.
Anaerobic
digestion
of
organic
material
is
not
associated
with
substantial
emissions
of
toxic
air
contaminants
(TACs).
Therefore,
there
would
be
no
health
risk
impacts
resulting
from
anaerobic
digestion
processes.
Any
subsequent
combustion
of
collected
digester
gas
for
the
purposes
of
generating
steam
or
electricity
or
operating
vehicles
would
result
in
pollutant
emissions.
Similar
to
natural
gas
and
other
fuels,
combusting
digester
gas
results
in
emissions
of
criteria
pollutants
(oxides
of
nitrogen,
NO
x
;
carbon
monoxide,
CO;
volatile
organic
compounds,
VOC;
particulate
matter,
PM;
and
oxides
of
sulfur,
SO
x
)
as
well
as
greenhouse
gases
(CO
2
,
CH
4
,
and
nitrous
oxide,
N
2
O).
Emissions
of
these
pollutants
from
combusting
digester
gas
vary
depending
on
the
type
of
combustion
device,
the
presence
of
air
pollution
control
equipment,
and
the
composition
of
the
gas,
but
would
be
similar
to
those
of
natural
gas
combustion
and
would
offset
natural
gas
combustion
emissions
for
energy
assumed
in
the
analysis
of
the
Draft
EIR.
While
it
is
unlikely
that
combustion
of
digester
gas
would
be
a
source
of
TAC
emissions,
even
if
the
composition
of
the
gas
were
to
result
in
TAC
emissions,
consistent
with
the
requirements
of
its
Policy
and
Procedure
Manual,
the
BAAQMD
would
require
that
such
combustion
not
exceeds
a
cancer
risk
of
10
in
one
million
or
a
chronic
or
acute
hazard
index
of
1.0,
and
would
deny
an
Authority
to
Construct
or
a
Permit
to
Operate
for
any
new
or
modified
source
of
3
Brisbane
Baylands
Final
EIR
2.9.1-5
May
2015