1. Sea Floor Habitats 
a. Current Situation The United States has not 
placed any habitats at depths below limits of 
saturated diving. Such deep habitats require pres- 
sure vessels in which a one-atmosphere environ- 
ment can be maintained. Vehicles capable of 
transporting men and materials to a bottom in- 
stallation will be needed to allow the habitat to 
remain on the bottom. Power sources, life support, 
and operational equipment must be contained 
within the habitat or in a satellite installation, 
because permanent wire cable contact with the 
shore or surface is undesirable. 
One advanced concept is the Naval Civil Engi- 
neering Laboratory’s Manned Underwater Station 
(Figure 32), designed for 6,000-foot depths. The 
station consists of two main cylinders, one for 
habitation and one for a nuclear power source, 
with small access and observation spheres above 
and below. 
Figure 32. Artist’s concept of a manned under- 
water station. (Navy drawing) 
b. Future Needs The first portable bottom labo- 
ratories and stations will likely accommodate only 
small crews of 15 to 25 men. However, if mining, 
industrial, or major military operations suggest the 
desirability of bottom installations, they may 
become substantially larger. 
For similar sizes, fixed bottom structures will 
be cheaper than portable habitats. However, for 
maximum response to changing situations, and for 
work at several locations the more extensive 
development and added construction expense for 
transportability will be justified. 
Such stations and attendant transfer and logis- 
tic vehicles could be positioned where military or 
commercial needs require, such as for recovery of 
scallops or nodules or for an extended salvage 
operation. Ocean exploration will disclose new 
areas for exploitation in which the ability to move 
manned habitats quickly may be a key to profit- 
able returns. 
Underwater inspection, maintenance, and repair 
will become increasingly important because deteri- 
oration usually accelerates with time. New tools, 
equipment, and nondestructive inspection tech- 
niques must be developed; the last, in particular, 
will be a formidable challenge. Underwater instal- 
lations must be specially designed for maintenance 
and repair in a manner compatible with submers- 
ible capabilities. Improved materials that resist the 
sea environment will be another important factor. 
2. In-Bottom Habitats 
a. Current Situation Construction of in-bottom 
habitats will depend on tunneling techniques long 
used for railroad, subway, automobile, and water 
tunnels. Over 100 undersea mining complexes 
exist under many tens of square miles of continen- 
tal shelf involving thousands of linear miles of 
openings. As many as 4,100 men work in a single 
undersea complex (Figure 33). However, all these 
Figure 33. Machine shop located in a mine 
1,500 feet below sea level off Newfoundland 
coast. (Navy photo) 
VI-93 
