—Facilities for pumping the oil wells after they 
stop flowing by natural pressure. 
4. Lag Between Exploratory and Production Drill- 
ing Capability 
The ability to explore and drill for petroleum 
resources in deep water exceeds the capability to 
produce once it is found. Recent lease acquisitions 
in depths beyond 600 feet exceed present produc- 
tion capability. Also, the problems and expenses 
of underwater production and well maintenance 
are much more extensive than those of explora- 
tion. 
Oil and gas in relatively shallow water are easier 
to produce on fixed platforms, because the pro- 
duction systems and pipelines are not significantly 
different from those on land. Many of these fields 
have been producing for years, but of hundreds of 
wells drilled in water depths greater than 200 feet, 
only a few have been brought into production. 
Costly production platforms on legs 200 to 300 
feet high have rendered many recovery operations 
economically impractical. Wells in great water 
depths also present problems of maintenance, and 
the pipelines required to connect these distant 
platforms to shore are proportionally more expen- 
sive. 
Some underwater wells in deep water already 
have been capped to await such developments as: 
(1) an increase in the price of crude oil and gas, (2) 
enough adjacent discoveries to justify a joint 
pipeline, or (3) technology advances that will 
make recovery from them profitable. 
Costs in shallow water can approach those of 
deep water under special high risk conditions as in 
Alaska’s Cook Inlet. Platforms in this location 
must withstand tidal currents up to eight knots 
which in the winter move pack ice as much as six 
feet thick past the installation four times a day. 
Each platform costs more than $10 million—an 
expenditure for a stable base that is a minimal cost 
on land. 
The largest four-legged platform is a 3,200 ton, 
43-well unit to be installed in 75 feet of water in 
Cook Inlet. Another unique platform rests on one 
column which stands on a base. Steel in the 
28-foot diameter column ranges from one to two 
inches thick, the thicker sections being in the areas 
buffeted by the pack ice (Figure 38). 
Figure 38. The monopod located in Cook Inlet, 
Alaska. The single-leg platform, installed in 1966, 
has minimized effects of ice loading and lends 
itself to rapid installation in strong currents. 
(Brown and Root photo) 
5. Automatically Controlled Platforms 
A completely automatic platform complex has 
been installed in the North Sea for gas extraction. 
The entire platform and all its generators, pumps, 
dehydrators, and other equipment run completely 
unattended with only occasional visits by super- 
visory and maintenance personnel. This platform is 
monitored from shore by closed circuit television 
that could also indicate fire or illegal trespassing. 
Such offshore wells are remotely controlled 
through automatic valve actuators receiving in- 
structions usually via microwave. In addition, 
these systems require communications equipment 
and an electric power source to operate the valve 
motors. Pneumatic or hydraulic valve actuators 
can be used, but these require continuous high- 
pressure air or hydraulic fluid. 
E. Pipelines 
Pipelines are laid in an offshore field to gather 
the oil or gas produced from individual wells into 
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