1
MEMORANDUM
TO:
The
316(
b)
Rule
Administrative
Record
FROM:
John
Sunda,
SAIC
DATE:
February
11,
2004
SUBJECT:
An
Analysis
of
the
Confidence
in
Accuracy
of
the
Phase
II
316b
Compliance
Cost
Modules.

INTRODUCTION
This
memo
provides
an
overview
of
the
confidence
in
the
accuracy
of
the
compliance
capital
and
O&
M
costs
developed
using
the
316(
b)
Phase
II
Compliance
Technology
Cost
Modules.
A
key
element
in
cost
estimation
is
the
available
data
and
information
about
site
conditions.
Some
site
conditions
are
favorable
to
design
and
construction
works
while
others
may
involve
higher
degrees
of
uncertainty.
In
sites
with
favorable
conditions
design
and
construction
costs
are
expected
to
be
lower
than
the
cost
of
the
same
project
designed
and
constructed
under
"
typical"
or
"
normal"
site
conditions.
On
the
other
end
of
the
spectrum,
the
costs
are
expected
to
be
significantly
higher
than
that
for
the
"
typical"
job
site.
The
cost
estimates
developed
for
the
316b
compliance
technologies
assume
a
"
typical"
rather
than
the
exceptional
job
site,
except
where
noted
below.

In
every
design
and
construction
endeavor
a
level
of
confidence
is
developed
based
on
many
factors.
These
factors
include
factual
or
data
attributes
and
non­
factual
or
information
attributes.
The
data
attributes
have
to
do
with
level
of
detail
that
is
available
to
the
designer,
the
estimator,
and
the
contractor.
Also
important
is
the
information
about
the
end
product
function
and
architectural
features
of
the
job
site
where
construction
or
installation
of
equipment
needs
to
take
place.
The
confidence
also
has
to
do
with
the
confidence
in
the
source
data
and
how
the
data
was
used
to
generate
the
information
and
confidence
in
the
experience
that
is
often
used
by
engineers
and
cost
estimators
to
bridge
gaps
in
the
available
data.
As
such,
many
professional
organizations
and
authorities
in
the
engineering
and
construction
arena
have
developed
scales
to
identify
necessary
confidence
levels
at
every
stage
of
a
project
in
order
to
keep
a
project
within
the
realm
and
context
of
reasonableness
within
budget
and
execution
potential
limits.

For
example,
the
American
Association
of
Cost
Engineers
International
(
AACEI)
recommends
the
following
three
construction
cost
estimating
categories
with
the
corresponding
different
levels
of
accuracy
shown
in
Table
A.
EPA
generally
develops
budgetary
level
cost
estimates
to
forecast
compliance
cost
estimates
for
a
regulation.
However,
for
the
316b
compliance
technology
cost
estimates,
EPA
took
an
additional
step
in
developing
costs
that
were
closer
to
definitive
or
preliminary
design
costs
estimates.
2
TABLE
A
Construction
Cost
Estimating
Categories
Category
Purpose
Timing
Expected
Accuracy
1)
Conceptual
Estimate
­
Preliminary
Estimates
for
Proposed
Projects,
­
Generally
Used
for
Screening
of
Alternatives
­
Major
equipment
is
sized
and
specified
­
Process
flow
is
approved
­
Utility
requirements
are
specified
­
Preliminary
plot
layout
+
50%
to
­
30%

2)
Budget
Estimate
­
To
commit
engineering
budget
­
To
commit
purchase
of
critical
delivery
of
equipment
­
Appropriation
request
­
Check
contractor's
bids
Same
as
above
except:
­
process
design
basis
is
approved
­
selection
of
alternatives
has
been
made
+
30%
to
­
15%

4)
Definitive
Estimate
­
Detailed
control
budget
­
Cost
control
and
reporting
­
Finalize
contract
structure
­
Fee:
adjust
or
convert
­
Plot
plan
finalized
or
approved
­
Equipment
size
and
specs
firm
­
Flow
diagrams
complete
­
Complete
set
of
specifications
­
Production
engineering
may
be
completed
up
to
40%
+
15%
to
­
5%

Source:
(
AACE
1996)

As
described
below
some
of
the
cost
components
such
as
equipment
costs
and
technologies
available
from
a
limited
number
of
providers
have
an
accuracy
level
that
is
much
higher
than
a
budgetary
cost
estimate.
In
general,
given
the
context
of
the
316b
developed
cost
estimates,
the
accuracy
of
any
module
is
not
expected
to
be
less
than
that
of
a
"
budget
estimate."

The
discussion
below
attempts
to
generally
assess
in
more
detail
the
accuracy
of
elements
of
the
cost
modules.
For
clarification
purposes,
examples
concerning
the
selection
of
assumed
values
used
in
the
technology
design
or
input
variables
are
presented
below.
In
order
to
ensure
that
the
national
totals
are
reasonably
accurate
or
exceed
median
values
high­
side
design
values
were
assumed
where
noted.

In
some
modules,
median
values
of
the
data
provided
by
the
detailed
questionnaire
facilities
are
3
assumed
for
facilities
where
specific
data
input
are
not
available
(
e.
g.,
short
technical
questionnaire
facilities).
In
some
cases
the
overall
median
is
used
and
in
others
waterbody
specific
medians
are
used.
The
use
of
medians
is
intended
to
produce
the
best
estimate
of
costs
at
the
national
level
by
equally
over­
and
under­
estimating
individual
facility
costs
as
a
result
of
the
assumed
median
value
being
higher
or
lower
than
the
actual
value.
A
select
set
of
modules
were
designed
to
err
on
the
high
side
(
i.
e.,
overestimating
the
costs)
because
of
the
known
unpredictability
of
job
sites
and
technology
performance.

Inaccuracies
due
to
regional
differences
in
labor
and
materials
costs
are
accounted
for
where
necessary
through
the
use
of
regional
cost
factors.
Where
unit
costs
are
based
on
RS
Means
data,
the
unit
costs
should
be
considered
as
having
an
accuracy
of
a
definitive
estimate
as
these
costs
are
derived
and
routinely
updated
using
numerous
national
construction
project
data
sources.

The
Agency
also
considered
the
elevated
costs
for
capital
and
operation
and
maintenance
costs
at
nuclear
stations.
These
costs
were
applied
as
numerical
multipliers
to
the
costs
discussed
below.
As
such,
the
analysis
of
confidence
levels
discussed
below
for
fossil­
fuel
facilities
will
apply
to
nuclear
facilities
as
well.

PASSIVE
SCREENS
Cost
Modules
Covered:

°
Module
#
4:
Add
Passive
Fine
Mesh
Screens
(
1.75
mm
mesh)
at
Shoreline
°
Module
#
7:
Relocate
Intake
to
Submerged
Offshore
with
Fine
Mesh
Passive
Screen
(
1.75
mm
mesh)
°
Module
#
9:
Add
Passive
Fine
Mesh
Screen
(
1.75
mm)
at
Inlet
of
Offshore
Submerged
°
Module
#
12:
Add
Very
Fine
Mesh
(
0.75
mm)
Passive
Screen
at
Shoreline
°
Module
#
13:
Add
Very
Fine
Mesh
(
0.75
mm)
Passive
Screen
at
Inlet
of
Offshore
Submerged
°
Module
#
14:
Relocate
Intake
to
Submerged
Offshore
with
Very
Fine
Mesh
(
0.75
mm)
Passive
Screen.

The
differences
between
the
fine
mesh
(
1.75
mm)
and
very
fine
mesh
(
0.75
mm)
screens
were
that
the
"
per
screen"
flow
rate
was
set
lower
for
finer
mesh
similar
sized
screens
based
on
vendor
recommendations.
The
per
screen
cost
was
slightly
higher
for
similar
sized
screens,
and
O&
M
cost
were
adjusted
upward
for
finer
mesh
due
to
higher
retention
of
debris
with
finer
mesh.
The
analysis
below
focuses
on
fine
mesh
screens
but
should
also
apply
to
the
very
fine
mesh
screen
modules.

Passive
Screen
Capital
Costs
Input
Variables
The
primary
input
variable
was
the
intake
design
flow.
Other
variables
included
saltwater
versus
4
freshwater,
and
distance
offshore.
To
reduce
inaccuracy
due
to
differences
in
distance
offshore,
costs
are
developed
for
4
distances
offshore;
20
meters
(
which
corresponds
to
the
"
near
shoreline"
modules
#
4
and
#
12),
125
meters,
250
meters,
and
500
meters.
As
can
be
seen
in
Table
B
the
distance
offshore
has
a
significant
effect
on
the
costs.
Inevitably
some
inaccuracy
will
exist
due
to
the
potential
mismatch
of
the
module
distance
and
the
actual
distance.
For
adding
passive
screens
to
existing
offshore
intakes
at
facilities
where
the
distance
was
known,
the
next
highest
module
distance
was
selected
with
a
maximum
of
500
meters.
In
general,
this
tended
to
bias
the
capital
costs
upward
but
increased
the
confidence
that
the
costs
would
not
be
underestimated.
However,
for
those
with
existing
distances
greater
than
500
meters
the
costs
were
biased
downward.
For
the
short
technical
questionnaire
facilities,
the
distance
offshore
for
existing
submerged
intakes
was
assumed
to
be
equal
to
the
median
value
for
the
data
provided
in
the
detailed
questionnaires
for
each
waterbody
category.
This
value
was
then
rounded
up
to
the
next
of
the
four
module
distances
to
increase
the
confidence
that
the
costs
would
not
be
underestimated.
The
assumption
that
there
would
be
sufficient
depth
for
larger
size
screens,
provides
a
potential
bias
of
costs
towards
the
low
side
where
high
design
flows
require
large
screens
to
be
installed
near
shore
in
shallow
water.
For
larger
flows,
shallow
water
requires
multiple
smaller
screens
which
would
tend
to
increase
screen
and
piping
costs.
To
limit
this
potential
bias,
facilities
requiring
multiple
large
screens
were
rarely
considered
as
candidates
for
near
shore
applications.

Capital
Cost
Components:

The
total
estimated
capital
costs
for
adding
passive
wedgewire
t­
screens
consists
of
the
following
cost
components:

°
Screens
°
Backwash
Equipment
°
Backwash
Air
Piping
°
Steel
Pipe
°
Connecting
Wall
The
proportion
and
significance
of
each
to
the
total
capital
cost
depends
on
the
specific
application.
The
proportion
of
the
total
for
each
component
varies
most
with
distance
offshore.
Table
B
presents
the
proportion
of
each
component
calculated
as
an
average
of
those
for
each
of
the
10
input
flow
values
ranging
from
2,500
to
163,000
gpm
for
the
shortest
(
20
meters)
and
longest
(
500
meters)
submerged
intake
pipes
in
freshwater
applications.
Each
component
cost
includes
installation
costs
and
is
discussed
separately
below.
5
TABLE
B
Relative
Proportion
of
Each
Capital
Cost
Component
for
Freshwater
Applications
for
Adding
Screens
to
Existing
Submerged
Intakes
and
Relocating
Submerged
Offshore
for
20
Meters
and
500
Meters
Offshore
Relocate
Passive
Screens
Offshore
Components
Add
to
Existing
Submerged
Intake
Relocate
Offshore
20
Meters
Offshore
500
Meters
Offshore
20
Meters
Offshore
500
Meters
Offshore
Screens
64%
20%
29%
6%

Backwash
Equipment
17%
6%
7%
2%

Backwash
Air
Piping
20%
74%
9%
24%

Steel
Pipe
0%
0%
28%
62%

Connecting
Wall
0%
0%
27%
6%

Screen
Costs
The
screen
cost
component
includes
the
sum
of
the
cost
of
the
screens,
installation,
mobilization,
and
steel
fittings.
Installation
and
mobilization
can
comprise
from
80%
of
the
screen
costs
for
low
flow
operations
to
about
20%
for
high
flow
operations.
The
screen
costs
were
obtained
from
a
vendor
who
reported
that
the
accuracy
of
the
screen
costs
as
that
of
a
detailed
estimate
(+
15%
to
­
5%)
(
Whitaker
2004).
The
installation
and
mobilization
costs
are
based
on
the
BPJ
application
of
vendor­
provided
cost
estimates
for
velocity
caps.
While
the
equipment
costs
were
reported
be
relatively
accurate,
vendors
of
nearly
all
of
the
technologies
have
noted
that
installation
costs
are
much
more
variable
and
dependent
on
site­
specific
conditions
making
a
"
typical"
estimate
potentially
less
accurate.
As
such,
the
installation
and
mobilization
component
costs
(
20%
to
80%
of
total
screen
costs)
should
be
viewed
as
having
the
accuracy
of
a
budget
estimate.

Actual
project
screen
costs
were
obtained
for
six­
48
in.
screens
installed
at
the
Zimmer
Power
Plant
on
the
Ohio
River.
The
reported
screen
equipment
cost
when
adjusted
to
2002
dollars
for
inflation
was
$
204,680.
Comparable
total
screen
costs
using
the
cost
module
component
data
was
$
190,000
for
Cu
Ni
screens.
In
this
example
the
actual
screen
costs
were
8%
higher
than
the
Module
Cost
and
are
well
within
the
estimated
accuracy
range.
6
Backwash
Equipment
The
backwash
equipment
costs
were
also
obtained
from
a
vendor.
This
backwash
equipment
cost
data
came
with
the
caveats
that
"
the
Air
Burst
system
is
very
custom,
based
upon
distance
from
screen,
multiple
compressors,
receiver
size,
controls,
etc."
Thus,
the
accuracy
of
this
cost
component
is
difficult
to
quantify
and
the
costs
provided
by
the
vendor
should
be
viewed
as
having
the
accuracy
of
a
budget
estimate
since
it
included
variation
due
to
differences
in
equipment
sizes.

Backwash
Air
Piping
The
costs
for
backwash
air
piping
is
based
on
unit
costs
reported
in
RS
Means
Costworks
2001
for
installed
stainless
steel
pipe
(
in
an
above
ground
application)
multiplied
by
an
underwater
installation
factor
of
2
which
was
derived
from
looking
at
similar
data
for
the
steel
pipe
installation
costs.
While
the
cost
of
materials
for
the
stainless
steel
pipe
should
have
the
accuracy
of
a
definitive
estimate,
the
installation
factor
was
developed
using
BPJ
and
should
be
viewed
as
having
the
accuracy
of
a
budget
estimate.

Steel
Pipe
The
steel
pipe
costs
were
derived
from
the
submerged
steel
pipe
cost
estimating
methodology
as
described
in
Economic
and
Engineering
Analyses
of
the
Proposed
Section
316(
b)
New
Facility
Rule,
Appendix
A,
but
modified
based
on
a
design
pipe
velocity
of
5
fps.
The
pipe
cost
estimate
is
the
result
of
a
detailed
engineering
estimate
and
should
have
the
accuracy
of
a
budget
estimate.
The
actual
methodology
used
in
the
installation
of
the
manifold
piping
may
differ
from
the
method
used
in
developing
the
module
costs.

The
use
of
different
pipe
installation
methods,
however,
does
not
necessarily
indicate
costs
will
vary
widely.
For
example,
a
comparison
of
the
bid
costs
provided
for
installation
(
using
a
coffer
dam
in
this
instance)
of
a
220
meter
10ft
diameter
steel
pipe
on
a
submerged
drinking
water
intake
on
the
Potomac
River
for
the
Fairfax
County
Water
Authority
was
$
2,856,000
for
the
wining
low
bid.
The
comparable
Module
component
for
a
250
meter
pipe
was
$
2,818,000.
Note
that
the
module
pipe
length
was
14%
greater
than
the
example,
but
the
cost
of
the
accepted
bid
was
within
nearly
one
percent
of
the
cost
predicted
by
the
module.
While
the
installation
method
was
different
the
costs
were
very
similar.

Connecting
Wall
The
connecting
wall
design
is
based
on
the
use
of
a
sheet
pile
using
sheet
pile
cost
from
RS
Means.
The
primary
independent
variable
used
to
develop
costs
for
different
flow
values
was
the
cross­
sectional
area
of
the
front
of
the
intakes
to
be
covered.
Several
general
assumptions
were
made
that
tended
to
bias
the
costs
of
this
component
upward,
including
assuming
an
existing
through
screen
velocity
of
1.0
fps
(
whereas
the
median
was
around
1.5
fps)
and
a
percent
open
7
area
of
50%
(
rather
than
68%
for
"
typical"
coarse
mesh
screens
cited
by
traveling
screen
vendors).
The
cost
was
developed
using
a
detailed
engineering
estimate
and
should
have
an
accuracy
of
a
budget
estimate
but
biased
somewhat
on
the
high
side.

Relocate
to
Submerged
at
Shoreline
or
Offshore
As
described
above
the
screen
equipment
costs
have
the
greatest
accuracy
(
approximately
+
15%
to
­
10%)
but
this
only
comprises
20%
to
80%
of
the
installed
screen
cost
which
itself
is
29%
to
6%
of
the
total
capital
cost
depending
on
distance
offshore.
Combined
the
screen
equipment
costs
component
(
accuracy
of
+
15%
to
­
10%)
constitutes
roughly
25%
to
1.2%
of
the
total
capital
cost.
The
remaining
components
are
considered
as
having
an
accuracy
of
a
budget
estimate
(+
30%
to
­
15%).
In
addition,
as
noted
above
several
of
the
assumed
engineering
values
were
selected
such
that,
on
average,
the
capital
costs
would
be
biased
towards
the
high
side.

Add
to
Existing
Submerged
Offshore
In
this
option
the
installed
screen
cost
represent
a
greater
portion
of
the
total
costs
(
64%
to
20%)
and
therefore
the
total
capital
cost
will
have
a
greater
overall
accuracy.
Combined
together,
the
screen
equipment
costs
component
(
accuracy
of
+
15%
to
­
10%)
constitutes
roughly
51%
to
4%
of
the
total
capital
cost.
The
remaining
components
are
considered
as
having
an
accuracy
of
a
budget
estimate
(+
30%
to
­
15%).
As
with
the
relocate
offshore
option,
the
non­
screen
costs
increase
as
the
distance
offshore
increases.
In
addition,
as
noted
above
several
of
the
assumed
engineering
values
were
selected
such
that,
on
average,
the
capital
costs
would
be
biased
towards
the
high
side.

Passive
Screen
O&
M
Costs
O&
M
Input
Variables
The
primary
independent
variable
was
the
intake
design
flow.
High
and
low
debris
was
selected
as
a
secondary
variable
to
increase
confidence
that
the
costs
would
be
accurate
for
different
environments.
Distance
offshore
and
saltwater
versus
freshwater
were
not
considered
as
additional
sources
of
variation
in
O&
M
costs.
However,
freshwater
and
saltwater
determinations
did
play
a
role
in
designation
of
the
debris
level.

O&
M
Cost
Components
O&
M
costs
consist
of
labor,
power
requirements
and
periodic
underwater
inspection
and
cleaning.
A
high
debris
and
low
debris
option
was
developed
for
each
scenario
to
increase
the
confidence
of
the
estimates
by
accounting
for
the
differences
in
backwash
frequency
and
underwater
inspection
and
cleaning
frequency
that
would
be
expected
for
waterbodies
with
higher
and
lower
amounts
of
debris.
Costs
for
existing
submerged
intakes
do
not
include
any
additional
dive
team
costs
above
that
which
is
already
being
performed
prior
to
the
installation
of
the
8
screens.
Table
C
presents
the
average
proportion
of
each
component
over
the
range
of
flow
values
costed
for
fine
mesh
screens.
As
can
be
seen
the
power
cost
component
represents
a
very
minor
proportion
and
therefore
will
not
be
discussed
further.

TABLE
C
Relative
Proportion
of
Each
O&
M
Cost
Component
for
Freshwater
Applications
for
Adding
Screens
to
Existing
Submerged
Intakes
and
Relocating
Submerged
Offshore
Relocate
Passive
Screens
Offshore
O&
M
Component
Add
to
Existing
Submerged
Intake
Relocate
Offshore
Low
Debris
High
Debris
Low
Debris
High
Debris
Power
1.6%
4.5%
2%
5%

Labor
64%
62%
98%
75%

Dive
Team
Inspection
&
Cleaning
35%
33%
0%
20%

Labor
The
O&
M
labor
rate
per
hour
is
$
41.10/
hr.
The
rate
is
based
on
Bureau
of
Labor
Statistics
(
BLS)
Data
using
the
median
labor
rates
for
electrical
equipment
maintenance
technical
labor
(
SOC
49­
2095)
and
managerial
labor
(
SOC
11­
1021);
benefits
and
other
compensation
are
added
using
factors
based
on
SIC
29
data
for
blue
collar
and
white
collar
labor.
The
two
values
were
combined
into
a
single
rate
assuming
90%
technical
labor
and
10%
managerial.
This
labor
rate
is
fairly
accurate
being
based
on
national
average
BLS
data
and
is
used
in
other
module
O&
M
cost
development
as
well.
The
number
of
hours
applied
is
based
on
vendor
quotes
of
several
hours
per
week
with
a
notation
that
during
certain
periods
some
systems
must
be
manned
24
hours/
day
for
a
week
or
more
during
seasonal
high
debris.
The
selected
rates
of
2­
4
hours
per
week
plus
one
week
at
24
hours
per
day
for
low
debris
or
3
weeks
24
hours
per
day
for
high
debris
are
based
on
BPJ
interpretation
of
the
vendor
supplied
information
for
"
typical"
operations.
It
is
expected
that
the
actual
labor
annual
total
will
be
quite
variable.
Therefore,
while
the
labor
dollar
per
hour
rate
is
very
accurate,
the
labor
hours
are
considered
to
have
a
moderate
accuracy
with
a
wide
range
resulting
in
the
derived
costs
being
that
of
a
budget
estimate.

Dive
Team
Inspection
and
Cleaning
The
dive
team
costs
are
based
on
a
vendor
quote
for
a
supervisor,
tender
and
diver,
including
equipment,
boat,
and
mobilization/
demobilizations.
Costs
are
calculated
in
single
day
increments.
These
costs
should
be
considered
as
fairly
accurate
for
typical
diver
costs.
However,
as
with
the
9
labor
hourly
requirements,
the
frequency
and
duration
of
the
dive
team
requirements
are
based
on
general
vendor
quotes
with
caveats
that
actual
frequencies
and
durations
may
vary
greatly
from
site
to
site.
As
such,
the
dive
team
costs
are
considered
as
having
an
accuracy
of
a
budget
estimate.

Several
facilities
with
submerged
intakes
were
surveyed
and
annual
underwater
inspection
and
cleaning
costs
were
reported
by
three
facilities,
the
total
annual
costs
were
$
3,800,
$
10,000,
and
$
30,000.
The
first
value
is
below
the
minimum
one
day
module
dive
team
cost
of
$
5,260
(­
28%)
and
the
$
30,000
value
is
greater
than
the
high
debris
annual
cost
of
$
18,480
(+
62%)
for
a
comparable
flow.
This
reported
range
confirms
that
Such
costs
do
vary
considerably
on
a
sitespecific
basis.
However,
it
does
show
that
EPA's
estimates
do
represent
a
middle
or
"
typical"
value.
Note
that
the
higher
value
was
for
a
facility
experiencing
zebra
mussel
problems
that
may
have
not
been
designed
to
prevent
this
problem.
The
EPA
module
technology
applied
to
such
situations
include
higher
up
front
costs
for
screen
materials
(
CuNi)
that
tend
to
inhibit
mussel
colonization.

Overall
O&
M
Considering
the
above
discussion,
the
O&
M
costs
for
passive
screens
should
be
considered
as
having
the
accuracy
a
budget
estimate
without
any
bias.

TRAVELING
SCREENS
Cost
Modules
Covered:

°
Module
#
1:
Add
Fish
Handling
and
Return
System
°
Module
#
2:
Add
Fine
Mesh
Traveling
Screens
with
Fish
Handling
and
Return
°
Module
#
11:
Add
Double­
Entry,
Single­
Exit
with
Fine
Mesh,
Handling
and
Return
Based
on
the
advise
of
traveling
screen
vendors,
facilities
receiving
technology
Module
#
1
received
costs
for
replacement
of
the
traveling
screen
units
as
well
as
the
addition
of
a
fish
return
sluice.
The
alternative
was
to
replace
only
the
baskets
and
screens
and
add
fish
spray
equipment.
This
was
based
on
vendor
advise
that
a
partial
retrofit
that
would
retain
a
portion
of
the
original
equipment
would
cost
approximately
75%
of
the
cost
of
replacement
units
saving
only
about
25%
but
possibly
compromising
system
effectiveness
and
longevity.
Thus,
this
was
a
conservative
(
high
cost
side)
assumption
that
could
offset
future
costs
that
would
be
difficult
to
quantify.
This
increases
the
confidence
in
the
O&
M
cost
estimates
for
module
#
1
by
eliminating
any
uncertainty
with
regard
to
future
performance
and
the
need
for
corrective
measures.

Facilities
where
module
2
was
specified,
received
different
costs
depending
on
whether
the
data
available
indicated
they
a
fish
handling
and
return
system
already
in­
place.
If
they
did
not,
then
the
compliance
costs
included
replacing
the
traveling
screens
as
well
as
adding
a
fish
return
sluice.
If
they
did,
then
only
the
costs
for
adding
fine
mesh
overlays
applied.
With
the
exception
of
10
Module
#
3
(
add
new
larger
intake),
the
screen
equipment
size
for
traveling
screens
is
limited
to
the
size
of
the
existing
intake.

In
general,
the
above
approach
increased
confidence
in
the
accuracy
of
the
capital
and
O&
M
costs
by
tailoring
the
cost
estimates
to
the
known
technology
in­
place.

Traveling
Screen
Capital
Costs
Input
Variables
The
cost
of
traveling
screens
are
dependent
on
both
the
height
(
well
depth)
and
width
of
screen
unit.
Screen
cost
data
indicates
that
two
screens
with
the
same
effective
screen
area
but
with
different
size
height
and
width
will
have
different
costs.
To
increase
the
confidence
in
the
cost
estimates
for
this
final
rule
applying
to
existing
facilities,
the
design
flow
was
combined
with
other
data
such
as
intake
water
depth
and
through­
screen
velocity
to
determine
the
calculated
total
effective
screen
width
of
the
existing
intake
screens.
Since
the
size
of
replacement
screens
is
limited
to
the
size
of
the
existing
intake
structure,
the
estimated
total
screen
width
was
considered
a
much
better
variable
for
estimating
screen
equipment
costs
compared
to
design
flow
alone.
For
all
facilities
the
percent
open
area
(
POA)
of
screens
already
in­
place
was
assumed
to
be
68%
which
was
identified
by
screen
vendors
as
the
prevalent
POA
for
coarse
mesh
screens.
One
vendor
said
that
approximately
97%
of
existing
intake
screens
use
coarse
mesh
with
3/
8
inch
mesh
upon
which
this
value
is
based.
Flow
data
and
through­
screen
velocity
data
were
available
for
most
facilities,
while
intake
water
depth
was
only
available
for
detailed
questionnaire
facilities.
Median
values
from
the
detailed
questionnaire
facility
data
were
assumed
for
those
without
data.
Well
depth
was
another
important
screen
sizing
variable.
In
order
to
simplify
the
effort
but
still
retain
confidence
in
the
costs
over
a
range
of
sizes,
costing
scenarios
for
five
different
well
depths
were
developed
(
10ft,
25
ft,
50
ft,
75
ft,
100
ft).
One
of
these
five
costing
well
depths
was
then
applied
to
each
facility
based
upon
the
actual
or
calculated
well
depth.
Calculated
or
actual
intake
well
depths
that
exceeded
approximately
20%
greater
than
any
category
was
assigned
to
the
next
highest
category.
In
general,
this
tended
to
bias
this
portion
of
costs
slightly
upward
as
the
majority
of
those
falling
in­
between
the
well
depth
categories
were
costed
for
deeper
wells.
In
many
cases
well
depth
data
was
available
but
if
not,
the
well
depth
was
assumed
to
be
1.5
times
intake
water
depth
which
was
the
median
value
for
those
facilities
that
had
provided
both
water
and
well
depth
data.
Other
variables
include
saltwater
versus
freshwater,
which
primarily
affected
screen
costs
due
to
differences
in
material
costs,
and
the
presence
of
a
canal
or
intake
channel.
Where
a
canal
or
intake
channel
was
present,
cost
for
the
added
fish
return
flume
length
was
added.

Capital
Cost
Components:

The
total
estimated
capital
costs
for
modifying
and/
or
adding
traveling
screens
consists
of
the
following
cost
components:
11
°
Traveling
Screens
°
Screen
Installation
°
Fine
Mesh
Overlays
°
Spray
Water
Pumps
°
Fish
Flume
°
Added
Fish
Flume
Length
for
Those
with
Canals
Table
D
presents
the
cost
components
and
the
percent
of
total
cost
of
each
component
for
a
single
10ft
wide
25
ft
deep
through­
flow
traveling
screen.
A
10
ft
wide
screen
was
selected
as
an
example
because
it
represents
a
commonly
used
standard
screen
size
and
the
25
ft
depth
was
selected
based
on
the
median
values
from
the
detailed
data.
Dual­
flow
screens
would
present
a
similar
cost
mix
as
shown
in
Table
D
but
with
slightly
higher
costs
for
the
screen
equipment
component.
Note
that
the
proportions
given
are
for
facilities
without
canals.
For
those
with
canals,
the
fish
flume
component
would
be
a
higher
proportion
depending
on
the
canal
length.

TABLE
D
Compliance
Module
Scenarios
and
Corresponding
Cost
Component
Relative
Proportions
for
10
ft
Wide
and
25
ft
Deep
Screen
Well
Compliance
Action
Cost
Component
Included
in
EPA
Cost
Estimates
Existing
Technology
Traveling
Screens
Without
Fish
Return
Traveling
Screens
With
Fish
Return
Module
2
­
Add
Fine
Mesh
Only
(
Scenario
A)
New
Screen
Unit
NA
0%

Screen
Installation
NA
0%

Add
Fine
Mesh
Screen
Overlay
NA
100%

Add
Spray
Water
Pumps
NA
0%

Add
Fish
Flume
NA
0%

Module
1
­
Add
Fish
Handling
Only
(
Scenario
B)
New
Screen
Unit1
Freshwater
67%
Saltwater
80%
NA
Screen
Installation
Freshwater
14%
Saltwater
9%
NA
Add
Fine
Mesh
Screen
Overlay2
0%
NA
12
Add
Spray
Water
Pumps
Freshwater
2%
Saltwater
1%
NA
Add
Fish
Flume
Freshwater
17%
Saltwater
10%
NA
Module
2
­
Add
Fine
Mesh
With
Fish
Handling
(
Scenario
C
and
Dual­
Flow
Traveling
Screens)
New
Screen
Unit
Freshwater
63%
Saltwater
74%
NA
Add
Fine
Mesh
Screen
Overlay
Freshwater
6%
Saltwater
7%
NA
Add
Spray
Water
Pumps
Freshwater
2%
Saltwater
1%
NA
Add
Fish
Flume
Freshwater
16%
Saltwater
9%
NA
1
Replace
entire
screen
unit,
includes
one
set
of
smooth
top
or
fine
mesh
screen.
2
Add
fine
mesh
includes
costs
for
a
separate
set
of
overlay
fine
mesh
screen
panels
that
can
be
placed
in
front
of
coarser
mesh
screens
on
a
seasonal
basis.
3
Does
not
include
initial
installation
labor
for
fine
mesh
overlays.
Seasonal
deployment
and
removal
of
fine
mesh
overlays
is
included
in
O&
M
costs.

Screen
Equipment
As
can
be
seen
in
Table
D
the
majority
of
the
screen
costs
are
for
the
screen
units.
Screen
equipment
costs
were
obtained
from
vendors,
one
set
for
freshwater
only
in
1999
and
one
set
for
freshwater
and
saltwater
in
2002.
EPA
found
that
the
2002
costs
for
freshwater
screens
were
about
10%
to
30%
less
than
the
1999
cost
even
after
adjusting
for
inflation.
The
screen
cost
data
were
reported
by
the
vendors
as
"
budget"
level
estimates
(
i.
e.,+
30%
to
­
15%).
EPA
chose
the
higher
1999
costs
(
adjusted
to
2001)
because
they
were
most
suited
for
application
to
the
selected
screen
size
scenarios
and
as
a
conservative
(
high
cost
side)
approach.
The
ratio
of
saltwater
to
freshwater
screens
from
the
2002
data
was
used
to
derive
corresponding
saltwater
screen
costs.
Thus,
the
screen
equipment
costs
for
both
freshwater
and
saltwater
have
an
accuracy
equivalent
to
budget
level
estimates
and
may
be
biased
on
the
high
side
by
10%
to
30%.

Screen
Installation
Costs
Screen
installation
costs
are
much
more
variable
than
the
equipment
costs
and
can
increase
by
30%
if
screens
must
be
installed
in
sections
due
to
overhead
obstructions.
Two
vendors
provided
values
that
differed
by
about
50%
but
all
noted
that
site­
specific
situations
made
estimating
"
typical"
installation
costs
was
difficult.
The
installation
costs
were
adjusted
for
screen
size
and
selected
to
span
the
range
of
costs
cited.
Thus,
the
installation
costs
should
be
considered
as
having
the
accuracy
of
a
budget
estimate.
13
Fine
Mesh
Overlays
Fine
mesh
overlays
are
calculated
as
a
percent
of
screen
costs.
A
vendor
quoted
that
the
cost
would
be
8
to
10%
of
the
screen
equipment
costs
and
EPA
chose
to
use
a
10%
factor
resulting
in
a
slight
bias
on
the
high
side.
Otherwise
these
costs
should
have
the
same
accuracy
as
the
cost
of
the
screen
equipment
alone.
The
assumption
of
using
fine
mesh
overlays
rather
than
permanent
fine
mesh
screens
for
scenario
C
would
be
a
conservative
assumption
for
locations
that
do
not
have
seasonal
debris
problems.
This
assumption
increases
the
confidence
that
the
module
would
not
underestimate
costs
where
seasonal
debris
problems
exist.

Spray
Water
Pump
Costs
As
show
in
Table
D,
the
spray
pump
costs
only
contribute
around
1%
to
2%
of
the
total
costs
and
thus
will
not
contribute
significantly
to
variations
in
the
data
accuracy.
However,
as
noted
in
the
O&
M
discussion
below
the
estimated
volume
of
spray
water
has
a
significant
effect
on
the
O&
M
costs.
Spray
water
pump
costs
are
derived
based
on
a
vendor
supplied
water
use
factor
per
ft
of
total
screen
width.
Only
the
additional
volume
needed
for
the
low
pressure
fish
spray
component
is
costed
for
additional
pumps.
A
range
of
26.6
to
74.5
gpm/
ft
total
flow
was
cited
by
vendors.
Only
one
vendor
gave
a
breakdown
between
the
two
requirements
as
17.4
gpm
for
debris
and
20.2
for
the
fish
spray.
EPA
chose
a
30
gpm
rate
for
the
fish
spray
as
a
conservative
(
high
end)
rate,
which
when
compared
to
the
single
20.2
gpm/
ft
example
may
bias
the
flow
upward
by
nearly
50%.
The
pump
equipment
and
installation
costs
are
based
on
flow
and
engineering
unit
costs
for
similar
equipment
and
thus
should
be
viewed
as
having
the
accuracy
of
a
budget
estimate
but
biased
towards
the
high
side.

Fish
Flume
The
cost
of
fish
return
flumes
will
vary
with
flow
volume
and
length,
and
other
site­
specific
factors.
All
facilities
that
did
not
already
have
a
fish
return
in­
place
received
costs
for
a
fish
flume.
The
flumes
are
sized
to
return
the
entire
flow
generated
(
60
gpm/
ft
screen
width)
which
as
noted
above
may
be
biased
toward
the
high
side.
A
screen
vendor
cited
flume
lengths
of
75
ft
to
150
ft
and
survey
data
for
facilities
without
canals
reported
a
length
of
30
ft
to
300
ft.
EPA
chose
the
high
end
of
this
range
of
300
ft
as
a
conservative
estimate
of
a
"
typical"
installation.
Thus,
the
flume
length
chosen
by
EPA
may
be
biased
upward
by
up
to
100%.
EPA
notes
that
in
some
tidal
applications
two
return
flumes
are
used
to
ensure
that
the
debris
is
deposited
downstream
and
this
assumption
ensures
that
such
situations
are
accounted
for.

For
those
facilities
that
reported
the
intake
was
at
the
end
of
a
canal,
an
additional
costs
was
added
to
account
for
the
added
distance
needed
to
reach
the
main
waterbody.
This
additional
length
was
set
equal
to
the
canal
length
and
was
an
additional
cost
above
the
300
ft
length.
Note
that
the
300
ft
length
provides
for
placement
of
the
debris
discharge
away
from
the
intake.
Flume
costs
include
costs
for
PVC
pipe
and
support
pilings
spaced
at
10
ft.
Costs
for
a
12
in
diameter
PVC
pipe
were
developed
from
RS
Means
data
and
then
converted
to
a
rate
of
$
10.15/
inch
dia.­
14
ft
length
including
sitework
and
indirect
costs.
Flume
diameter
was
calculated
based
on
an
assumed
velocity
when
full
of
1.5
fps.
As
such,
the
flume
costs
are
based
on
engineering
design
assumptions
that
are
conservative
(
high
side)
for
the
"
typical"
site
to
increase
confidence
that
this
component
will
not
be
underestimated.
Therefore,
the
cost
estimates
should
be
viewed
as
having
the
accuracy
of
a
budget
estimate
and
may
be
biased
towards
the
high
side.

Module
2
Scenario
A
The
relative
accuracy
of
these
cost
estimates
should
be
equal
to
that
of
the
screen
equipment
(+
30%
to
­
15%)
and
the
cost
factor
(
10%)
which
could
be
biased
toward
the
high
side
by
an
additional
10%
(
the
Agency
used
the
10%
factor
as
opposed
to
the
9%
midpoint
between
8%
and
10%).

Module
1
Scenario
B
The
screen
equipment
costs
which
have
an
estimated
accuracy
of
+
30%
to
­
15%
accounts
for
67%
to
80%
and
may
be
biased
toward
the
high
side
by
10%
to
30%
for
the
example
screen.
The
remaining
components
are
considered
as
also
having
an
accuracy
of
a
budget
estimate
and
also
may
be
biased
toward
the
high
side
for
spray
water
pumps
and
flume
length.

Module
2
Scenario
C
The
screen
equipment
costs
which
have
an
estimated
accuracy
of
+
30%
to
­
15%
accounts
for
63%
to
74%
of
the
costs
and
may
be
biased
toward
the
high
side
by
10%
to
30%
for
the
example
screen.
The
remaining
components
are
also
considered
as
having
an
accuracy
of
a
budget
estimate
and
also
may
be
biased
toward
the
high
side
for
spray
water
pumps
and
flume
length.

Module
11
Scenario
C
(
Dual­
flow)

The
capital
costs
for
dual­
flow
screens
were
developed
by
multiplying
the
through­
flow
screen
total
costs
by
factors
recommended
by
a
vendor.
Thus,
the
component
proportions
and
relative
accuracy
should
be
similar
to
that
for
through­
flow
screens.

Traveling
Screen
O&
M
Costs
Baseline
O&
M
Costs
O&
M
costs
for
facilities
that
have
traveling
screens
in­
place
are
calculated
on
a
net
basis.
In
other
words
a
cost
estimate
is
calculated
for
the
existing
intake
screens
and
then
subtracted
from
the
compliance
technology
O&
M
cost
estimate.
As
such,
there
is
an
additional
O&
M
cost
option
for
traveling
screens
without
fish
returns.
In
general,
this
option
involves
less
operating
time,
no
extra
fish
spray
pumping
and
as
a
result
labor,
power,
and
parts
replacement
costs
(
less
wear
and
tear)
are
lower.
All
assumption
for
this
baseline
option
are
based
on
vendor
estimates
of
"
typical"
15
operations.
In
addition,
the
costs
derived
under
Module
2
Scenario
B
also
served
as
the
basis
for
baseline
O&
M
costs
for
facilities
with
existing
traveling
screens
with
fish
returns.

Net
cost
calculations
were
limited
to
facilities
where
the
compliance
technology
was
an
upgraded
version
of
the
traveling
screen
technology
or
where
the
existing
traveling
screen
technology
was
being
replaced
in
function
and
would
no
longer
be
required.
An
example
is
where
fine
mesh
passive
screens
replaced
traveling
screens.
An
example
where
baseline
costs
were
not
deducted
is
the
addition
of
fish
barrier
nets.
The
accuracy
of
the
net
O&
M
costs
are
therefore,
a
combination
of
the
accuracies
of
the
positive
and
negative
components.
When
deviations
of
the
module
results
from
the
actual
costs
of
both
components
(
baseline
and
compliance)
have
the
same
sign
(+
or
­),
the
differences
will
tend
to
cancel
each
other
out
somewhat.
But
when
they
have
different
signs,
the
accuracy
of
the
net
value
will
be
reduced.

For
facilities
with
fixed
screens
or
other
non­
traveling
type
screen
technologies,
no
baseline
costs
were
deducted
because
there
was
no
reliable
way
to
estimate
baseline
O&
M
costs.
This
results
in
a
bias
toward
the
high
side
of
net
O&
M
costs
for
these
facilities
since
even
for
fixed
screens
there
would
be
certain
amount
of
labor
associated
with
periodically
inspecting
and
cleaning
the
screens.

O&
M
Input
Variables
The
O&
M
costs
use
the
same
input
variables,
total
screen
width,
well
depth
and
saltwater
versus
freshwater
as
the
capital
costs
(
see
discussion
above).

O&
M
Cost
Components
O&
M
costs
consist
of
labor,
power
requirements,
and
parts
replacement.
Table
E
presents
the
corresponding
O&
M
cost
component
relative
proportions
for
10
ft
wide
and
25
ft
deep
screen
well.
16
TABLE
E
Compliance
Module
Scenarios
and
Corresponding
O&
M
Cost
Component
Relative
Proportions
for
10
ft
Wide
and
25
ft
Deep
Screen
Well
Compliance
Action
Cost
Component
Included
in
EPA
Cost
Estimates
Existing
Technology
Traveling
Screens
Without
Fish
Return
Traveling
Screens
With
Fish
Return
Module
2
­
Add
Fine
Mesh
Only(
First
Column)
and
Add
Fine
Mesh
With
Fish
Handling(
Second
Column)
(
Scenarios
A
and
C)*
Basic
Labor
Freshwater
35%
Saltwater
29%
Freshwater
35%
Saltwater
29%

Overlay
Labor
Freshwater
15%
Saltwater
12%
Freshwater
15%
Saltwater
12%

Motor
Power
Freshwater
2%
Saltwater
2%
Freshwater
2%
Saltwater
2%

Pump
Power
Freshwater
30%
Saltwater
26%
Freshwater
30%
Saltwater
26%

Parts
Freshwater
18%
Saltwater
31%
Freshwater
18%
Saltwater
31%

Module
1
­
Add
Fish
Handling
Only
(
Scenario
B)
Basic
Labor
Freshwater
41%
Saltwater
33%
NA
Overlay
Labor
0%
NA
Motor
Power
Freshwater
2%
Saltwater
2%
NA
Pump
Power
Freshwater36
%
Saltwater
29%
NA
Parts
Freshwater
21%
Saltwater
35%
NA
*
The
O&
M
costs
are
assumed
to
be
he
same
for
compliance
scenarios
A
and
C
but
the
net
costs
will
be
different
for
each
since
the
baseline
technologies
are
different.

Basic
Labor
A
vendor
provided
general
guidelines
for
estimating
basic
labor
requirements
for
traveling
screens
as
averaging
200
hours
and
ranging
from
100
to
300
hours
per
year
per
screen
for
coarse
mesh
screens
without
fish
handling
and
double
that
for
fine
mesh
screens
with
fish
handling
(
Gathright
2002).
If
the
range
shown
represented
a
single
screen
size
then
the
accuracy
would
be
roughly
17
+
50%
to
­
50%,
however
a
good
portion
of
this
variation
in
hours
is
related
to
intake
size.
Estimates
for
various
screen
sizes
were
scaled
to
span
these
ranges.
Thus,
the
accuracy
of
the
basic
labor
cost
estimates
should
be
considered
as
having
the
accuracy
of
a
budget
estimate
because
it
included
estimated
hours.
The
hourly
wage
rate
is
fairly
accurate
as
discussed
under
passive
screens
above.

Overlay
labor
Overlay
labor
is
based
on
recommended
screen
change­
out
times
per
screen
panel.
The
number
of
screen
panels
is
very
accurate
for
each
screen
and
so
the
accuracy
of
the
labor
estimate
is
associated
with
the
accuracy
of
the
estimated
time
for
placing
each
screen
overlay
and
whether
the
annual
frequency
estimate
of
once
per
year
was
correct.
As
such,
it
is
reasonable
to
consider
the
overlay
labor
estimate
as
having
an
accuracy
of
a
definitive
estimate.

Motor
and
Pump
Power
Power
requirements
for
the
motors
comprises
only
2%
of
the
total
and
therefore
will
not
be
discussed.
The
spray
water
pump
requirements,
however,
could
be
significant.
Several
aspects
of
the
pump
power
requirements
tend
to
bias
these
costs
upward.
The
first
as
described
in
the
pump
capital
costs
above
is
that
the
flow
rate
chosen
was
somewhat
biased
toward
the
high
side.
Secondly,
the
pump
power
requirements
are
based
on
the
entire
flow
being
pumped
to
the
high
pressure
needed
for
debris
removal.
If
the
low
pressure
stream
results
from
passing
through
a
regulator
from
a
high
pressure
pump
then
this
is
a
valid
assumption.
However,
if
a
separate
set
of
low
and
high
pressure
pumps
are
used,
then
this
assumption
will
result
in
an
overestimation
of
the
pump
energy
and
therefore
power
requirements.
As
the
flow
requirements
are
based
on
engineering
estimates,
it
is
reasonable
to
consider
the
pump
power
estimate
as
having
the
accuracy
of
a
budget
estimate
but
potentially
biased
toward
the
high
side.

Parts
replacement
These
costs
are
based
entirely
on
proportions
of
the
screen
equipment
costs
using
rough
estimates
provided
by
a
vendor.
As
such,
it
is
reasonable
to
consider
the
pump
power
estimate
as
having
the
accuracy
of
a
budget
estimate
but
potentially
biased
on
the
high
side
since
it
is
based
on
a
factor
multiplied
by
the
screen
equipment
costs.

Overall
O&
M
Costs
for
Through­
flow
Screens
In
general,
the
Agency
views
the
best
way
to
quantify
the
accuracy
of
the
components
as
being
on
the
order
of
a
conceptual
estimate
with
bias
towards
the
high
side
for
the
components
as
noted.

Dual­
flow
Screens
The
O&
M
costs
for
dual
flow
screens
(
Scenario
C
only)
were
calculated
as
a
fixed
proportion
of
18
through­
flow
screen
costs
reported
by
a
vendor
as
the
typical
values
they
have
observed.
As
this
factor
itself
is
a
rough
estimate,
the
dual­
flow
screen
O&
M
estimates
will
reflect
similar
accuracies
as
the
through­
flow
screens.

LARGER
INTAKES
Cost
Module
Covered:

°
Module
#
3:
Add
New
Larger
Intake
Structure
with
Fine
Mesh,
Handling
and
Return
Larger
Intake
Capital
Costs
Input
Variables
In
this
case
the
independent
variable
was
the
estimated
"
compliance
total
screen
width"
which
was
calculated
in
a
similar
manner
as
the
baseline
total
screen
width
used
in
the
traveling
screen
cost
estimates.
As
with
the
traveling
screens,
use
of
screen
sizes,
rather
than
flow
alone,
increases
the
confidence
in
the
accuracy
of
the
estimates
Differences
in
calculating
the
compliance
screen
width
include
using
a
through­
screen
velocity
of
1.0
fps
(
instead
of
the
actual
velocity
or
data
median
of
1.5
fps
that
was
used
for
the
baseline)
and
a
percent
open
area
(
POA)
of
50%
instead
of
68%
that
was
used
for
baseline
total
screen
width.
The
50%
POA
is
consistent
with
use
of
fine
mesh
screens.
In
this
case
the
independent
variable
may
be
biased
toward
the
low
side
if
facilities
select
a
lower
through­
screen
velocity
than
1.0
fps.
This
same
independent
variable
was
used
for
estimating
the
capital
and
O&
M
costs
for
dual­
flow
traveling
screens
installed
in
the
new
larger
intake.

Overall
Accuracy
The
new
larger
intake
costs
are
based
on
a
detailed
engineering
estimate
of
costs
for
a
larger
intake
located
just
in
front
of
the
existing
intake.
A
review
of
the
construction
components,
component
quantities
and
indirect
costs
does
not
indicate
any
items
that
may
have
been
estimated
in
a
way
that
would
tend
to
bias
the
cost
estimates
either
high
or
lower.
Unit
costs
are
based
on
costs
reported
in
RS
Means
Costworks
2001.
Considering
the
detailed
nature
of
the
estimation
method,
the
cost
estimate
should
be
viewed
as
having
the
accuracy
of
a
budget
estimate.

Larger
Intake
O&
M
Costs
No
separate
O&
M
costs
were
derived
for
the
structure
itself
since
the
majority
of
the
O&
M
activities
are
covered
in
the
O&
M
costs
for
the
traveling
screens
to
be
installed
in
the
new
structure.

FISH
BARRIER
NETS
19
Cost
Module
Covered:

°
Module
#
5:
Add
Fish
Barrier
Net
Barrier
Net
Capital
Costs
Input
Variables
In
this
case
the
independent
variable
was
the
design
intake
flow.
A
secondary
variable
was
freshwater
versus
saltwater.
Water
depth
was
considered
in
the
development
of
saltwater
barrier
nets
but
a
single
depth
close
to
the
median
value
reported
by
facilities
was
used
in
the
application.
Different
support
and
anchor
strategies
were
used
in
freshwater
and
saltwater.
These
different
approaches
to
freshwater
and
saltwater
applications
increases
the
confidence
in
the
cost
estimates
by
accounting
for
differences
in
design
due
to
the
presence
of
tidal
currents
in
saltwater
environments.
Research
indicated
that
nets
are
designed
on
a
site­
specific
basis
and
that
limited
engineering
guidelines
to
follow
exist.
Therefore,
the
barrier
net
costs
are
based
on
design
and
cost
data
from
two
facilities
with
barrier
nets
that
had
similar
net
velocities.
The
estimates
were
not
just
simple
scaled
costs
but
rather
an
evaluation
of
each
cost
component
was
performed
and
then
scaled
for
different
sizes.
Barrier
net
costs
are
primarily
based
on
the
required
net
size
and
support
structures/
equipment.
Two
facilities,
one
on
a
lake
and
another
on
an
estuary,
reported
essentially
the
same
velocity
of
0.06
fps.
Lacking
more
detailed
engineering
guidelines,
use
of
actual
reported
net
velocities
was
determined
to
be
the
best
method
to
develop
relatively
accurate
net
costs.

Freshwater
Barrier
Nets
(
Scenario
A)

Net
costs
are
based
on
the
unit
costs
in
dollars/
sq
ft
for
both
the
installed
net
and
a
back­
up
replacement
for
the
example
facility.
The
freshwater
unit
costs
include
costs
for
shipping,
floats
and
anchors.
The
freshwater
facility
cost
data
indicated
that
the
unit
costs
used
may
be
biased
slightly
toward
the
high
side
if
shallower
nets
are
used
(
e.
g.,
10
ft
or
less).
The
example
facility
had
a
net
depth
of
20
ft.
The
total
reported
installation
cost
was
split
into
a
fixed
component
of
20%
(
based
on
BPJ)
and
a
variable
dollar/
sq
ft
component.
While
this
module
will
provide
a
definitive
estimate
quality
estimates
of
the
net
costs
at
facilities
similar
to
the
example
facilities,
the
fact
that
there
are
limited
guidelines
indicates
that
actual
designs
may
vary
considerably
tending
to
temper
the
accuracy
of
this
module
to
an
accuracy
of
a
conceptual
design
estimate.

Saltwater
Barrier
Nets
(
Scenario
B)

In
this
scenario,
net
costs
are
based
on
using
two
concentric
nets,
supported
on
pilings
as
is
the
case
with
the
example
facility.
The
costs
for
the
nets
are
base
on
the
costs
cited
by
both
the
facility
and
its
supplier.
Costs
for
the
pilings
are
based
on
engineering
design
using
the
20
ft
spacing
at
the
example
facility
and
RS
Means
unit
costs
for
barge
driven
piles.
Costs
were
derived
for
depths
of
10
ft,
20
ft,
and
30
ft.
However,
in
developing
the
compliance
cost
20
estimates,
only
the
20
ft
depth
was
used.
In
the
case
of
this
saltwater
net
design,
shallower
depths
will
tend
to
drive
costs
upward
due
to
the
requirement
for
more
pilings.
While
this
module
will
provide
definitive
estimate
quality
estimates
of
the
net
costs
at
facilities
similar
to
the
example
facilities,
the
fact
that
there
are
no
guidelines
indicates
that
actual
designs
may
vary
considerably
tending
to
temper
the
accuracy
of
this
module
to
an
accuracy
of
a
conceptual
design
estimate.

Barrier
Net
O&
M
Costs
Input
Variables
O&
M
costs
use
the
same
independent
variables
as
capital
costs.
Duration
of
deployment
was
also
considered.

Freshwater
Barrier
Nets
The
O&
M
costs
are
based
on
reported
labor
requirements
and
net
replacement
rates.
The
period
of
deployment
is
also
important.
The
example
facility
reported
a
deployment
period
of
120
but
others
reported
longer
periods.
EPA
chose
to
base
the
costs
on
a
deployment
period
of
240
days
as
a
conservative
(
high
side)
estimate.
EPA
scaled
up
the
labor
hours
cited
by
the
facility
and
added
an
additional
net
section
replacement
step.
Costs
for
the
example
facility
were
developed
and
then
converted
to
a
straight
line
cost
curve
by
assuming
20%
of
costs
were
fixed.
While
this
module
will
provide
a
definitive
estimate
quality
estimates
of
the
net
O&
M
costs
at
facilities
similar
to
the
example
facilities,
as
with
the
O&
M
costs,
the
fact
that
there
are
no
guidelines
indicates
that
actual
operations
may
vary
considerably
tending
to
temper
the
accuracy
of
this
module
to
an
accuracy
of
a
budget
estimate
with
a
potentially
biased
toward
the
high
side.

EPA
notes
that
other
O&
M
costs
reported
in
literature
are
often
less
than
what
results
from
the
cost
module.
For
example,
1985
O&
M
cost
estimates
for
the
JP
Pulliam
plant
($
7,500/
year,
adjusted
to
2002
dollars)
calculate
to
$
11,800
(
compared
to
$
57,000
for
the
example
facility)
for
a
design
flow
roughly
half
that
of
example
facility.
This
suggests
the
scenario
A
estimates
represent
the
high
end
of
the
range
of
freshwater
barrier
net
O&
M
costs
(
biased
upward
as
noted
above).
Other
O&
M
estimates
that
also
were
lower,
however,
do
not
describe
the
cost
components
that
are
included
and
can
not
be
used
for
comparison
since
they
may
not
represent
all
cost
components.

Saltwater
Barrier
Nets
The
saltwater
barrier
net
O&
M
costs
are
based
on
the
net
maintenance
contractor
costs
plus
replacement
net
costs.
Nearly
all
of
the
O&
M
labor
for
Chalk
Point
facility
is
performed
by
a
marine
contractor
who
charges
$
1,400
per
job
to
simultaneously
remove
the
existing
net
and
replace
it
with
a
cleaned
net.
The
reported
annual
job
frequency
was
used
along
with
the
reported
net
replacement
rate.
As
with
the
capital
costs,
while
this
module
will
provide
a
accuracy
of
a
definitive
estimate
at
the
example
facility,
the
fact
that
actual
designs
may
vary
considerably
21
indicates
that
the
accuracy
of
this
module
can
be
considered
as
having
the
accuracy
of
a
budget
estimate
VELOCITY
CAPS
Cost
Module
Covered:

°
Module
#
8:
Add
Velocity
Cap
at
Submerged
Inlet
EPA
identified
only
one
vendor
that
supplied
preconstructed
velocity
caps.
This
appears
to
be
primarily
due
the
fact
that,
for
many
installations,
velocity
caps
are
custom
designed
and
constructed.

Velocity
Cap
Capital
Costs
Input
Variables
The
primary
input
variable
was
design
intake
flow.
Freshwater
versus
saltwater
was
an
additional
variable
that
affected
equipment
costs.

Capital
Cost
Components:

Capital
costs
consist
of
equipment,
installation,
and
mobilization/
demobilization.
For
higher
flows,
multiple
heads
are
used
with
the
costs
including
inlet
piping
modifications.
The
saltwater/
freshwater
differences
are
due
to
use
of
different
materials.
The
vendor
was
very
confident
about
the
equipment,
installation,
and
mobilization/
demobilization
costs
as
they
had
performed
numerous
recent
jobs.
The
mobilization/
demobilization
costs
were
reported
as
a
range
of
$
15,000
to
$
30,000.
This
was
applied
such
that
the
range
spanned
the
range
of
flow
rates
costed.

The
proportion
of
the
total
for
equipment
costs
ranged
from
39%
for
a
5,000
gpm
freshwater
intake
to
71%
for
a
350,000
gpm
freshwater
intake
and
were
roughly
7%
less
for
saltwater.
Due
to
the
apparent
limited
number
of
prefabricated
cap
suppliers
and
the
confidence
expressed
by
the
vendor
the
equipment
portion
should
be
considered
as
having
an
accuracy
of
a
definitive
estimate
and
the
remainder
having
an
accuracy
of
a
budget
estimate.
This
estimate
of
accuracy
should
be
limited
to
the
use
of
prefabricated
velocity
caps.
As
noted
above
many
are
custom
designed
built
onsite
and
in
those
instances
costs
may
vary
considerably.
This
will
tend
to
temper
the
accuracy
of
this
module
to
an
accuracy
somewhere
between
a
budget
and
a
conceptual
estimate
when
multiple
methods
of
construction
are
considered.

Velocity
Cap
O&
M
Costs
Input
Variables
22
The
primary
input
variable
was
design
intake
flow.
Freshwater
versus
saltwater
was
not
considered
as
significant
source
of
valiance
in
the
O&
M
costs.

O&
M
Cost
Components
Since
this
was
a
passive
technology,
O&
M
costs
were
limited
to
periodic
inspection
and
cleaning
by
a
dive
team.
The
same
per
day
dive
team
costs
that
were
applied
to
the
passive
screen
O&
M
costs
are
applied
to
the
velocity
cap
O&
M
costs.
As
such,
the
dive
team
costs
are
considered
as
fairly
accurate
but
the
duration
and
frequency
estimates
are
considered
as
less
accurate
resulting
in
an
overall
accuracy
of
a
budget
estimate.

AQUATIC
FILTER
BARRIERS
Cost
Module
Covered:

°
Module
#
6:
Add
Aquatic
Filter
Barrier
Net
(
Gunderboom)

Currently
only
one
vendor
(
Gunderboom
Inc.)
is
available
to
design
install
this
technology.
The
technology
has
been
demonstrated
but
is
still
somewhat
in
the
developmental
stage.

Aquatic
Filter
Barrier
Capital
Costs
Input
Variables
Design
intake
flow
was
the
primary
variable.

Capital
Costs
The
cost
data
was
provided
for
three
flow
values
by
the
vendor
in
1999
prior
to
any
full
scale
installations.
Three
different
capital
costs
representing
low,
average
and
high
costs
were
provided.
These
costs
have
been
adjusted
for
inflation.
The
average
costs
were
selected
to
served
as
the
basis
for
compliance
costs
for
this
module.
No
updated
costs
based
on
recent
experience
were
made
available.
Given
the
lack
of
recent
experience
input
the
cost
estimates
should
be
considered
as
having
an
accuracy
somewhere
between
a
budget
ands
a
conceptual
estimate.
Also
note
that
additional
filter
fabric
grades
with
different
(
mostly
larger)
pore
sizes
are
now
available.
An
increase
in
pore
size
can
reduce
the
lateral
forces
acting
on
the
barrier
resulting
in
the
ability
to
reduce
the
required
barrier
total
effective
area.
This
in
turn
can
result
in
reduced
costs.

The
vendor
recently
provided
a
total
capital
cost
estimate
of
8
to
10
million
dollars
for
full
scale
MLESTM
system
at
the
Arthur
Kill
Power
Station
in
Staten
Island,
NY.
The
vendor
is
in
the
process
of
conducting
a
pilot
study
with
an
estimated
cost
of
$
750,000.
The
NYDEC
reported
the
permitted
cooling
water
flow
rate
for
the
Arthur
Kill
facility
as
713
mgd
or
495,000
gpm.
23
Applying
the
cost
equations
results
in
a
total
capital
cost
of
$
8.7,
$
10.1
and
$
12.4
million
dollars
for
low,
average
and
high
costs,
respectively.
These
data
indicate
that
the
inflation
adjusted
cost
for
an
average
cost
estimate
in
this
application
are
within
the
accuracy
range
of
a
budget
estimate.
However,
the
cost
estimates
provided
by
Gunderboom
are
themselves
estimates
and
may
or
may
not
accurately
reflect
project
costs
after
completion.
The
vendor
estimate
for
this
project
do
however,
indicate
the
vendors
confidence
in
the
module
estimates
at
least
in
this
flow
range.
The
vendor
had
expressed
a
concern
that
for
low
flow
applications
the
module
costs
may
be
too
high.
The
range
of
module
results
(
low
and
high)
shown
for
the
above
example
are
consistent
with
budget
estimate
accuracy
when
compared
to
the
average.

O&
M
Costs
Input
Variables
Design
intake
flow
was
the
primary
variable.

O&
M
Costs
O&
M
costs
are
for
the
operation
of
the
airburst
system
and
fabric
curtain
maintenance.
The
cost
estimates
were
obtained
in
a
similar
manner
as
the
capital
costs
but
in
this
case
there
was
no
recent
corroboration
of
the
original
estimates.
The
range
between
the
low,
average,
and
high
cost
estimates
indicate
that
the
average
O&
M
cost
estimates
should
be
considered
as
having
an
accuracy
of
a
conceptual
estimate
and
the
cost
estimates
may
be
somewhat
more
accurate
for
higher
flows.
24
REFERENCES
AACE.
American
Association
of
Cost
Engineers.
Certification
Study
Guide.
AACE
International.
1996.

Whitaker,
J.
Hendrick
Screens.
Telephone
contact
report
with
John
Sunda,
SAIC
regarding
accuracy
of
Passive
Screen
Costs.
February
3,
2004.
