2.
Response
to
Comments
2.9
Individual
Responses
to
Comments
from
Organizations
The
statement
referenced
in
this
comment
is
a
factual
statement
regarding
the
constituents
of
concern
analyzed
in
MACTEC’s
groundwater
monit
oring
since
2008.
This
statement
makes
no
assertions
regarding
the
source
of
the
contaminants
that
are
identified,
and
thus
neither
confirms
nor
refutes
any
assertions
by
Kinder
Morgan
regarding
the
source
of
MTBE
present
on
its
property.
The
in-situ
groundwater
treatment
applied
to
the
groundwater
underlying
consisted
of
enhanced
reductive
dechlorination
(ERD)
12
,
and
was
found
effective
when
the
chlorinated
solvents
were
at
high
concentrations
in
the
groundwater
and
less
effective
when
the
chlorinated
solvents
were
at
lower
concentrations
in
the
groundwater.
Reductive
dechlorination
of
chlorinated
alkenes
in
aquifers
can
be
enhanced
through
the
injection
of
readily
degradable
carbonaceous
materials
such
as
molasses,
whey,
or
vegetable
oil.
Microbial
degradation
of
the
injected
carbon
consumes
available
electron
acceptors
such
as
oxygen
and
nitrates
and
forces
the
aquifer
microbial
communities
into
utilization
of
alternative
electron
acceptors
such
as
ferric
iron
and
sulfates.
When
sulfate-reducing
or
methanogenic
conditions
develop,
chlorinated
alkenes
such
as
PCE,
TCE,
and
cis-1,2-DCE
can
be
rapidly
dechlorinated
(Payne
et
al.).
Ultimately,
however,
the
regulatory
authority
and
responsibility
to
determine
the
specific
remedial
technologies
to
be
undertaken
within
the
Baylands
lies
with
the
RWQCB
and
DTSC.
This
comment
provides
no
evidence
in
support
of
its
assertion
that
the
assessment
in
the
Draft
EIR
is
incorrect.
The
section
of
the
Draft
EIR
referenced
in
the
comment
is
specific
to
the
soil
excavation
and
removal
at
the
sludge
traps
of
the
former
Schlage
Lock
facility
within
San
Francisco,
placement
of
clean
fill
in
the
excavations,
and
subsequent
testing
of
the
soil
matrix
at
that
location.
Additional
remedial
activities
performed
at
that
location
include
soil
vapor
extraction.
As
shown
in
its
heading,
Table
4.G-4
reports
the
maximum
concentration
of
total
petroleum
hydrocarbons
mostly
as
Bunker
C
oil
from
sampling
in
August
2006
for
groundwater
wells
in
Information
on
the
specific
wells
generating
the
concentrations
identified
in
Table
4.G-4
is
not
available,
nor
is
the
specific
location
of
testing
wells
in
2006
critical
to
the
analyses
of
the
Draft
EIR
since
groundwater
was
remediated
by
pump
and
treat
technology
from
1995
through
2008
when
in-situ
remedial
activities
were
initiated.
12
Enhanced
reductive
dechlorination
(ERD)
is
a
groundwater
remedial
technology
that
entails
injection
of
a
mixture
of
highly
biodegradable,
soluble,
and
colloidal
organic
carbon
into
a
solvent-contaminated
aquifer
formation.
Brisbane
Baylands
Final
EIR
2.9.1-50
May
2015