Document ID: EPA-HQ-OW-2002-0049-0022
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:
November
4,
2002
Company
Name:
Chalk
Point
Power
Station
Street
Address:

City/
State/
ZIP:

Person
Contacted:
Patrick
Langley
Title:
Environmental
Mgr
Telephone
#:
301­
843­
4439
Called
to
inquire
about
fish
barrier
net
design
and
operation
especially
operating
costs.

He's
been
at
that
plant
since
1971,
back
before
the
nets
were
used,
they
used
to
have
to
frequently
clean
out
the
condensers
after
just
2
weeks
they
were
removing
a
dump
truck
load
of
debris
including
crabs
and
other
debris.
Now
with
the
nets
in­
place,
they
recently
went
for
99
days
before
a
shut
down
(
they
try
to
shut
down
during
lower
demand
between
Friday
and
Monday)
and
only
pulled
out
about
a
5
gallon
bucket
full.
Originally
they
tried
using
poles
similar
to
what
fishermen
use
but
found
that
they
were
to
easily
pushed
over
­
so
use
pilings
instead.
There
is
a
separate
set
of
pilings
for
each
of
the
two
nets.
Pilings
are
about
18
to
20
ft
apart
­
enough
space
so
a
boat
can
go
between.
The
pilings
extend
above
the
water
surface
by
about
6
ft.

The
nets
are
supported
on
spikes
in
the
pilings
near
the
top
and
are
not
connected
anyplace
else.
When
put
in
place
the
weighted
lower
end
of
the
net
is
placed
outward
from
the
pilings
so
that
net
forms
an
"
el"
shape
profile.
They
have
had
no
problems
with
sealing
the
bottom
using
this
method.

They
do
not
have
problems
with
abrasion
on
the
pilings
but
they
do
have
problems
sometimes
with
watermen
who
between
pulling
traps
go
up
to
their
nets
and
fish
alongside.
They
damage
the
nets
when
their
boats
come
up
against
the
pilings
with
the
net
in
between
where
the
up
and
down
wave
action
damages
the
nets
or
their
props
get
caught.
They
sometimes
have
problems
with
beavers
also.

They
have
debris
problems
with
jellyfish,
colonial
hydroids
and
virtocella
(
sp?),
a
spongelike
organism.
They
use
a
two
net
system
to
deal
with
debris
where
the
outer
net
with
a
1.25
inch
stretch
removes
85%
of
the
debris
and
the
inner
net
removes
another
85%+.
They
tried
smaller
mesh
at
0.5
inch
stretch
and
found
that
too
much
debris
(
colonial
hydroids)
got
caught
on
the
net.

Concerning
the
nets,
each
net
consists
of
three
nets
approximately
275­
300
ft
long
and
27
ft
deep.
The
specs
for
1.25
in
mesh
net
recently
purchased
for
$
4,131
each
was:

°
275
ft
long
by
27
ft
wide,
°
#
252
knotless
nylon
netting,
°
5
inch
rope
on
top
with
floats
every
6
ft
°
5/
16
inch
galvanized
line
on
bottom
For
the
similar
nets
with
.75
inch
mesh
were
$
3,936
each.
Normally
the
smaller
mesh
netting
costs
more.
This
is
a
new
supplier
"
Nylon
Net
Company"
in
Memphis
TN.

Concerning
O&
M
costs,
the
$
7,500
answer
in
the
questionnaire
is
incorrect.
It
should
be
more
like
$
75,000
and
may
be
a
typo.
They
pay
a
marine
contractor
$
1,400
a
job
to
remove,
repair,
clean,
and
replace
the
netting
for
both
nets.
They
pay
for
52
to
54
net
change­
outs
every
year
with
frequency
as
often
as
two
per
week
during
the
summer,
and
every
two
weeks
during
the
winter.
Removal
and
replacement
of
a
net
is
done
in
one
step
with
one
boat
removing
a
net
starting
at
one
end
and
a
second
boat
putting
the
replacement
net
in
place
right
behind
the
first
boat
so
the
time
the
area
is
open
is
minimized.
The
contractor
then
takes
the
net
to
their
dock
where
they
clean
and
repair
it
for
the
next
net
change­
out.
The
contractor
uses
a
diver
to
make
sure
the
bottom
of
the
net
is
set
properly.
They
buy
the
equivalent
of
a
new
set
of
nets
generally
about
every
3
years.

Based
on
this,
the
O&
M
costs
include:
°
53
x
$
1,400
=
$
74,200/
year
for
net
maintenance
°
6
(
nets)
/
3
years
*
$
4,100
=
$
8,200
year
In
past
they
took
the
nets
down
during
the
winter
because
of
ice.
But
they
had
still
problems
with
perch
impingement
in
January.
Then
their
contractor
and
biologists
came
up
with
a
method
for
suspending
the
net
about
3
ft
below
the
surface.
The
perch
tend
to
be
near
the
bottom
and
they
haven't
had
too
much
problem
with
fish
or
debris
passing
over
the
nets.