Document ID: EPA-HQ-OW-2004-0002-0529
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2004-11-30T05:00Z

Cooling
Water
Intake
Structure
(
CWIS)
Information
Data
Required
Rig
Information
Rig
Name
Rowan
Gorilla
II
Rowan
Gorilla
III
Rowan
Gorilla
IV
Rig
Type
Jack­
up
LeTourneau
Gorilla
class
Total
Installed
Power
Generation
Capacity
7950
HP
Number
of
Cooling
Water
Intake
Structures
(
CWISs)
5
Brief
description
of
each
CWIS
(
e.
g.,
sea
chest,
simple
pipe)
2
sea
chests
3
simple
pipe
Rough
dimensions
of
each
CWIS
and
indicate
whether
onboard
CWIS
has
an
existing
flange
Sea
chest
 
6"
pipe
with
Simple
pipes
 
18"
ID
pipes
Screen
type
(
e.
g.,
strainer,
wedge
wire)
with
mesh
size
Sea
chests
 
14"
x14"
wire
mesh
screens
Simple
pipes
­­
12
1
½
"
x18"
slots
Total
Design
Specifications
for
Daily
Maximum
Water
Intake
Volume
of
each
CWIS
1,727,964
to
3,024,000
gal
(
41,142
to
72,000
bbls)
Total
Daily
Water
Intake
Volume
of
each
CWIS
(
Set­
up/
Drilling)
1,727,964
to
3,024,000
gal
(
41,142
to
72,000
bbls)
Design
Specs
for
Through
Screen
Velocity
of
each
CWIS
(
i.
e.,
Q=
V*
A)
(
Set­
up/
Drilling)
1.51
to
2.65
fps
List
of
Purposes
of
Cooling
Water
Intakes
(
e.
g.,
cool
crude
oil,
produced
water,
power
generators,
drill
pipe
brakes)
Brake
water
cooling,
engine
oil
cooling,
electric
motor
cooling
List
of
Purposes
of
Non­
cooling
Water
Intakes
(
e.
g.,
fire
water,
hotel
loads)
Fire
main,
ballast,
sanitary,
pits,
drill
water,
hotel
loads,
distiller
input,
washdown
Total
Volume
of
Water
Intake
for
Ballasting,
Duration
of
the
Ballast
intake,
and
the
Through
Screen
Velocity
of
the
Ballast
intake
4,022,508
gal
(
95,744
bbls)
Duration
=
18­
24
hours.
Velocity:
1.19
 
2.08
fps
Mitigation
Measures
for
reducing
Exotic
Species
Migration
through
Ballast
water
The
rig
does
not
carry
ballast/
preload
water
from
location
to
location.
It
is
taken
on
and
dumped
at
the
same
location.
Mitigation
Measures
for
reducing
Impingement
and
Entrainment
of
Aquatic
Organisms,
as
well
as
Bio­
fouling
Prevention
Measures
Sea
chest
screens,
basket
strainers
Is
the
Rig
equipped
with
a
Radiator
Cooling
System
for
the
Main
Engines?
Yes