Document ID: EPA-HQ-OW-2002-0049-0171
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2003-03-19T05:00Z

316B
RULE
TELEPHONE
LOG
Name
of
Caller:
John
Sunda,
SAIC
Date:
August
2,
2002
&
Sept
9,
2002
Company
Name:
Hendrick
Screen
Company
Street
Address:

City/
State/
ZIP:
Owensboro,
KY
Person
Contacted:
John
Whitaker
Title:
Sales
Manager
Telephone
#:
270­
685­
5138
August
2,
2002
Called
to
inquire
about
passive
screen
costs
and
technical
issues
per
question
list.

Response
to
QUESTIONS
FOR
PASSIVE
SCREEN
VENDORS
Hendrick
Screen
Co
August
2,
2002
General
1.
Are
there
any
specific
types
of
locations,
waterbodies,
or
regions
where
applications
are
limited?
None
come
to
mind
2.
What
are
the
issues
or
limitations
regarding
retrofitting
large
volume
systems
with
passive
screens?
What
is
the
largest
volume
intake
where
you
have
installed
passive
screens
or
have
been
consulted
for
cost
estimates?
Largest
they
make
is
8
ft
diameter,
60
in
diameter
is
common
3.
What
portion
of
intake
modification
work
do
you
do?
For
example,
if
retrofitting
traveling
screen
intakes
with
passive
screens,
do
you
provide
only
the
screen
equipment
or
do
you
also:
They
only
provide
the
screens
sometimes
a
little
more
but
he
does
not
have
a
feel
for
installation
costs.

­
Provide
manifold
pipe
and
fittings
No
­
Provide
steel
plates
or
other
fittings
to
cover
existing
intake
opening
with
t­
screen
pipe
attachment
No
­
Provide
installation
No
4.
What
is
the
recommended
range
or
typical
design
through­
screen
intake
velocity
and/
or
approach
velocity?
Since
the
application
being
considered
here
is
in
response
to
a
requirement
to
reduce
entrainment
and
impingement,
what
is
the
practical
upper
limit
for
ensuring
acceptable
performance?
Generally
.5
in
east
.4
approach
in
west.
They
have
installed
flat
screens
with
3
fps
through
screen
velocity.

5.
What
range
of
screen
mesh
opening
sizes
do
you
consider
to
be
"
fine
mesh?"
When
facilities
examine
and/
or
select
finer
mesh
to
reduce
entrainment,
what
is
the
most
common
mesh
size?
On
west
coast
generally
function
of
location
and
type
of
fish
(
1.75
mm
is
typical).
On
east
coast
1/
8
in
is
common
some
larger
some
smaller.
A
screen
with
0.069
in
(
1.75
mm)
slot
and
wire
has
50%
open
area.

Shoreline
Intake
Retrofit
6.
When
does
it
make
more
sense
to
place
the
t­
screens
further
offshore?
Usually
water
from
offshore
has
better
quality
and
is
cooler.
Presence
of
recreational
traffic
can
be
an
issue.
Best
to
give
boaters
a
warning
before
airburst
­
some
places
use
a
warning
siren/
horn.

7.
We
assume
that
moving
the
intakes
from
the
shoreline
to
near
shore
or
offshore
into
public
waterways
will
involve
more
public
and
government
consultation
and
permitting.
Do
you
have
any
knowledge
or
examples
of
how
this
may
affect
costs?
No
knowledge.

8.
Are
most
near
shore
retrofit
installations
performed
by
divers
or
is
a
coffer
dam
type
structure
used
to
provide
a
dry
working
environment?
What
conditions
affect
the
selected
method
of
installation?
Both
occur.
No
suggestion
Installing
Passive
Screens
Offshore.

The
following
questions
involve
the
options
of
adding
passive
screens
to
existing
offshore
intakes
and
relocating
shoreline
intakes
offshore.

9.
Do
you
have
any
experience
with
installing
passive
screens
on
submerged
offshore
intakes
that
previously
had
none?
No
experience
If
so:
­
Please
provide
relevant
information
such
as
facility
name
&
location,
cost
data,
technical
data,
and
general
layout.
If
not
available,
who
should
we
contact
for
such
information?

10.
For
rivers/
lakes
with
boat
traffic,
what
are
the
recommended
clearance
depths
(
depth
of
water
above
the
screen)?
At
least
one
screen
diameter.
11.
Do
you
have
any
experience
with
or
knowledge
of
converting
shoreline­
based
intakes
to
submerged
offshore
intakes?
No
Knowledge
If
so:
­
At
what
facilities
was
this
done?
­
What
specifically
was
done
and
what
portions
of
the
existing
system
were
retained?
­
What
are
the
major
cost
components?

12.
For
large
volume
offshore
intakes,
we
assume
an
array
of
t­
screens
may
be
necessary
for
each
pipe.
Did
not
ask
this
question.
If
so:
­
What
sort
of
retrofit
construction
would
be
necessary?
­
Could
the
manifold
be
manufactured
onshore
and
installed
by
divers,
or
would
some
sort
of
underwater
manifold
construction
be
necessary?
­
Please
describe
construction
components,
example
costs,
and/
or
contacts
for
estimating
costs.

13.
Please
provide
delivered
equipment
costs
for
t­
screens
the
three
materials
we
discussed
(
freshwater
Stainless
304,
Stainless
316
and
copper
nickel
alloy)
using
fine
mesh
sizes
(
e.
g.,
1.75
mm).
See
screen
sizes
below.

­
T­
24
­
T­
36
­
T­
48
­
T­
60
­
T­
72
­
T­
84
­
T­
96
(
or
largest
standard
screen
size)
Are
there
any
savings
for
multiple
unit
orders?
Also
provide
table
correlating
flow
for
each
screen
for
typical
(
e.
g.,
0.5
fps)
design
through
screen
and/
or
approach
velocity.
14.
How
do
t­
screen
costs
compare
to
traveling
screens
with
similar
performance
requirements?

15.
What
equipment
materials
do
you
recommend
(
or
are
commonly
selected)
for
freshwater
and
for
corrosive
environments
such
as
brackish
and
saltwater?
­
304
Stainless
Steel
for
freshwater
­
316
Stainless
Steel
for
saltwater
­
Copper
Nickel
for
Zebra
Mussels
16.
What
waterbodies
are
experiencing
problems
with
Zebra
mussels,
and
how
much
extra
are
the
equipment
costs
for
special
alloy
construction
or
comparable
materials?
Did
not
ask
17.
Please
provide
equipment
cost
of
this
corrosion
resistant
equipment
or
provide
relative
cost
difference
compared
to
freshwater
unit,
such
as
a
cost
factor
or
percent
increase?
18.
In
corrosive
environments
such
as
saltwater
where
stainless
steel
or
copper
nickel
alloys
are
used
for
the
screens
what
type
of
materials
are
recommended
for
the
pipe
manifold
components?
Similarly
what
type
of
pipe
manifold
materials
are
recommended
where
special
alloys
are
employed
in
freshwater
to
control
Zebra
Mussels?

19.
Please
provide
delivered
and/
or
installed
costs
for
an
air
burst
backwash
system,
including
air
burst
distribution
and
control
equipment,
air
connection
tubing
and
fittings
for
systems
with
flows
from
2,000
gpm
to
500,000
gpm,
or
relative
costs
in
comparison
to
the
tscreen
equipment
costs.
Will
send
question
via
email
20.
Please
provide
information
concerning
passive
screen
installation
costs
for
both
shoreline
and
submerged
offshore
intakes,
particularly
as
compared
to
equipment
costs.
He
did
not
have
first
hand
knowledge
but
would
send
us
a
list
of
contractors
we
could
contact.

September
9,
2002
Called
top
inquire
about
O&
M
costs
and
components
Air
Backwash
Labor
Equipment
Labor
One
hour
per
day
is
too
much,
at
most
several
hours
per
week.
Most
of
the
equipment
has
alarms
so
there
is
no
need
to
monitor
equipment.
Equipment
will
not
need
any
significant
replacement
costs
for
a
long
time.

Air
Backwash
Frequency
Some
report
performing
backwash
once
per
week
­
this
would
represent
the
low
end
where
debris
loading
is
low.
Some
regulators
in
California
are
trying
to
require
once
every
15
minutes.
He
thinks
once
per
hour
would
represent
the
very
high
end
of
the
range.
A
frequency
in
the
range
of
4
­
5
times
per
day
would
probably
be
"
typical."

Compressor
Operation
Generally
the
compressors
are
sized
to
recharge
the
accumulator
once
every
30
to
60
minutes.
He
will
review
cost
&
screen
data
previously
sent
and
will
provide
air
requirements.
I
suggested
he
provide
Hp
of
the
compressor
which
will
help
develop
power
requirement
estimates.

He
said
some
of
the
larger
intakes
request
two
compressors
with
one
as
a
backup
but
this
was
not
part
of
costs
given.

Misc
I
asked
about
frazil
ice,
he
said
that
some
operators
have
gotten
some
improvement
by
providing
a
continuous
stream
of
bubbles
through
the
screen.
He
suggested
I
contact
people
in
Ontario
Canada
for
their
experience.

He
noted
that
in
locations
with
poor
current
there
may
be
a
requirement
to
physically
remove
debris
from
the
area
if
it
is
not
carried
away
after
backwashing