Document ID: EPA-HQ-OW-2004-0002-0201
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2004-11-29T05:00Z

TO:
316(
b)
Phase
II
Docket.

FROM:
Timothy
Connor
SUBJECT:
Effect
on
National
Costs
of
Combination
Cooling
Systems
and
Strategic
Flow
Reduction
DATE:
11/
29/
04
For
the
development
of
compliance
technology
costs,
the
Agency
considered
facilities
with
recirculating
systems
in­
place
to
need
no
technology
upgrades.
For
the
purposes
of
the
cost
analysis
the
Agency
defined
facilities
with
recirculating
systems
as
only
those
facilities
with
recirculating
cooling
systems
for
the
facility's
entire
intake
system.
If
a
facility
had
a
combination
of
intakes
that
utilized
oncethrough
and
recirculating
systems,
the
Agency
treated
the
facility
as
a
full
once­
through
facility.
In
addition,
if
a
facility
had
a
once­
through
or
combination
system
and
exercised
strategic
flow
reductions
(
as
reported
in
questions
26
of
the
detailed
questionnaire),
the
Agency
still
treated
the
facility
as
a
full
oncethrough
facility.

Combination
Cooling
Systems
Fifty
facilities
reported
combination­
cooling
systems
in
the
316(
b)
survey
(
in
the
short­
technical
or
detailed
questionnaire).
The
Agency
analyzed
the
intake­
level
and
cooling
system­
level
information
reported
in
the
survey
for
each
of
these
facilities.
The
Agency
found
that
the
median
percentage
of
overall
facility
flow
associated
with
the
recirculating
intake
feed
was
5.3
percent.
Therefore,
95
percent
of
the
facility's
flow
would
be
associated
with
the
once­
through
intakes.
Overall,
this
fact
reinforces
the
Agency's
assumption
that
costs
for
these
facilities
with
combination
cooling
systems
are
relatively
accurate.

Nonetheless,
the
Agency
attempted
to
gauge
the
degree
to
which
national
costs
may
be
overstated
by
examining
these
facilities
with
combination
cooling
systems
and
adjusting
their
technology
upgrade
costs
to
reflect
the
fact
that
a
recirculating
intake
at
the
facility
may
have
lesser
requirements
than
as
assumed.
Because
the
Agency
determined
that
5
percent
of
the
total
facility
intake
would
be
typically
associated
with
the
recirculating
intake,
to
which
the
Agency
assigned
costs
for
reducing
entrainment
and/
or
impingement
through
technology
upgrades,
the
Agency
adjusted
those
annual
cost
items
that
are
primarily
a
function
of
flow
by
multiplying
by
 
5
%.
The
cost
items
that
are
primarily
a
function
of
flow
include
capital
cost,
O&
M
cost,
and
pilot
study
costs.
For
adjustments
to
downtime
costs
the
Agency
necessarily
examined
the
portion
of
the
plant's
intakes
associated
with
the
recirculating
system.
Typically,
the
recirculating
portion
of
the
cooling
system
corresponded
to
one
of
several
intakes
at
the
facility.
The
most
common
occurrence
was
for
one
of
two
intakes
to
be
dedicated
to
a
recirculating
system
and
the
other
to
a
once­
through
configuration.
The
average
number
of
intakes
at
each
of
the
facilities
with
combination
cooling
systems
was
close
to
three
intakes.
A
frequent
occurrence
also
was
for
one
of
three
intakes
to
be
dedicated
to
the
recirculating
system.
Rarely
was
more
than
three
intakes
reported,
and
in
these
cases
multiple
intakes
were
generally
associated
with
a
recirculating
system.
Based
on
these
facts,
the
Agency
believes
that
a
reasonable
characterization
for
the
"
typical"
combination
cooling
system
in
the
data
base
was
for
one
of
three
intakes
to
correspond
to
a
recirculating
system
and
the
others
to
be
dedicated
as
once­
through.
Hence,
for
the
case
of
downtime
costs,
the
Agency
considered
a
reasonable
adjustment
to
be
one­
third
of
the
cost
of
the
downtime
at
the
facility­
level.
The
logic
is
that
should
a
generating
unit
with
a
unique
intake
not
require
a
downtime,
yet
the
Agency
assign
one,
then
the
cost
of
the
downtime
for
the
facility
would
be
overestimated.
Because
the
typical
configuration
for
the
combination
cooling
system
if
one
facility
of
three
2
dedicated
to
the
recirculating
system,
then
a
facility­
wide
downtime
assumption
would
potentially
overstate
downtimes
by
one­
third,
provided
all
units
roughly
generate
equivalent
amounts
of
electricity.
This
is
a
relatively
conservative
assumption
due
to
the
fact
that
in
the
cases
the
Agency
is
familiar
with,
the
recirculating
systems
typically
are
associated
with
the
newest
generating
units
at
the
plant.
Therefore,
significantly
more
than
one­
third
of
the
plant­
wide
generation
may
come
from
the
recirculating
portion.

For
the
purposes
of
determining
the
extent
to
which
costs
may
be
overstated
for
these
facilities,
the
Agency
calculated
for
each
of
the
50
combination
cooling
system
facilities
an
annualized
adjustment
cost.
These
costs
totaled
approximately
$
3.7
million
annually
(
in
2002
$).

Facilities
Utilizing
Strategic
Flow
Reductions
Eleven
facilities
reported
in
the
detailed
questionnaire
that
they
utilize
strategic
flow
reduction.
The
Agency
examined
the
assumed
entrainment
and/
or
impingement
requirements
it
utilized
for
the
technology
cost
development
and
found
that
five
of
the
strategic
flow
reduction
facilities
utilize
significant
strategic
flow
reductions
and
were
assigned
entrainment
technology
upgrades.
The
Agency
considers
that
this
may
overstate
costs
for
this
portion
of
facilities
given
that
the
median
flow
reduction
percentage
was
40
percent.
Strategically
implemented,
an
annual
flow
reduction
of
40
percent
(
targeted
to
periods
of
spawning
and
the
presence
of
large
numbers
or
high
density
of
organisms)
could
assist
a
facility
in
achieving
entrainment
reductions
comparable
to
the
entrainment
reduction
targets
of
the
final
rule.
Overall,
the
fact
that
the
Agency
identified
only
five
such
facilities
reinforces
the
Agency's
assumption
that
costs
for
these
facilities
with
strategic
flow
reduction
are
relatively
accurate
in
the
record.
Nonetheless,
the
Agency
analyzed
the
difference
in
costs
attributable
to
the
entrainment
technology
upgrades
assigned
for
these
facilities
to
the
cost
of
impingement
controls.

For
the
purposes
of
determining
the
extent
to
which
costs
may
be
overstated
for
these
facilities,
the
Agency
calculated
an
annualized
adjustment
cost
for
each
of
the
5
entrainment­
upgrade
facilities
already
utilizing
strategic
flow
reduction.
These
costs
totaled
approximately
$
4.7
million
annually
(
in
2002
$).
The
Agency
utilized
the
cost­
cost
test
correction
factor
of
2.148
for
converting
between
impingement
only
and
entrainment
and
impingement
requirements.

Overall
Change
to
National
Cost
Estimates
The
Agency
estimates
that
it
has
assigned
approximately
$
8.4
million
(
in
2002
average
$)
annually
to
all
of
these
identified
facilities.
These
costs
may
be
costs
potentially
avoided
by
facilities
in
compliance
with
the
rule
requirements.