Submarine Disposal of Industrial Waste
C. A. RAMBOW, President
Montgomery Research, Inc.
Pasadena, California
INTRODUCTION
Disposal of industrial wastes can be accomplished in many ways. The use of a
submerged outfall sewer and diffuser in the ocean (or in an estuary river, or other
body of water) is not universally applicable but where conditions permit its use, it
can be a highly satisfactory, economical and troublefree system. The purpose of this
paper is to review current practices in application and design of these systems and to
outhne the procedures involved in design.
A submerged diffuser should be considered when there is a large volume of
receiving water and when the character of the waste is such that direct disposal to
surface water is inconsistent with pollution control considerations. This method of
disposal may or may not require treatment of the waste prior to disposal, depending
on the individual circumstances. The matter of treatment is beyond the scope of this
paper and must be dealt with on an individual basis. However, to generalize, disposal
of highly mineralized waste water to an ocean does not constitute pollution of the
latter in the absence of specific offending ions; and many organic and inorganic
materials not normally present in ocean water may be satisfactorily disposed of
thereto because of the available factors of dilution, dispersion, oxidation and other
self-purification or assimilative phenomena that occur in large bodies of water.
Frequently, submarine disposal is more economical than more thorough treatment and direct discharge to small streams or other surface water bodies.
CONSTRUCTION
Design of an ocean outfall and diffuser system involves consideration of three
principal parameters. These are: first, the material of the outfall itself and the
method of installation; second, the means for anchoring the outfall and diffuser on
the ocean floor or in whatever body of water it is installed; and third, the design of
the waste diffuser.
The material of the pipehne can be selected on the basis of compatibility with
the waste stream and/or receiving water and the economics of fabrication and installation. While ocean outfalls have been successfully constructed of virtually every
type of pipe material available, one of the most promising techniques is the use of
steel pipe welded into a single unit and pulled into place from the onshore fabrication point by means of a barge equipped with winches and anchored offshore.
This technique reduces to a minimum the difficulties involved in underwater construction which normally calls for divers to assemble the pipehne and complete the
joints. In the pulling technique, sections of pipe are welded together and the joints
completed ashore to produce units with a length of up to several hundred ft. These
are then pulled into position by the barge. As the tail end of each unit nears the
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