This paper discusses the Coast Guard's development and application of filter-coalescers in removing oil from waste water, and the parallel development of small, on-line oil-in-water monitors. The success of these efforts allows full compliance with anti-pollution regulations.
A case history is presented of a semiautomatic installation on a Coast Guard cutter. This and similar work permitted the Coast Guard to purchase equipment for its fleet by the competitive bid process. Similar installations are well suited for use aboard off-shore supply craft and crew boats.
In Public Law 92-500, the "Federal Water Pollution Control Act Amendments of 1972", Congress declares "that it is the policy of the United States that there should be no discharges of oil or hazardous substances into or upon the navigable waters of the United States, adjoining shorelines, or into or upon the waters of the contiguous zone." The law further prohibits discharge of oil "in harmful quantities", which has been determined in regulations (40 CFR 110. 3) to include discharges which:
Violate applicable water quality standards, or
Cause a film or sheen upon or discoloration of the surface of the water or adjoining shorelines or cause a sludge or emulsion to be deposited beneath the surface of the water or upon adjoining shorelines.
The stated U. S. goal is to prohibit the discharge of oily wastes into all waters of the world by no later than the end of the decade. The time is approaching when the discharge of oily bilge and ballast water on the high seas may no longer be legally permissible.
The problem of oily water disposal has plagued engineers and captains of ships for years. Some of the efforts taken by shipboard engineers have included reducing oil and water leaks and distributing engine room bilge water to other bilges or to an empty fuel tank when in port for later disposal at sea. The Coast Guard has a vigorous pollution prevention "and enforcement program. Routine anti-pollution flights are conducted by both fixed-wing aircraft and helicopters. New technology is being used as equipments are developed. For instance, Coast Guard aircraft are now being equipped with remote sensing devices in the infra-red and ultraviolet ranges to detect oil slicks. Civil penalties may be antipipated. Criminal offenses with more severe penalties may also result if the Coast Guard is not notified when an oil discharge occurs. Costs of clean-up of even comparatively small oil spills can be substantial.
Very few shore facilities are available to dispose of large quantities of oily water. Fewer-yet are convenient to use and none are inexpensive. Even if shore disposal facilities were available and convenient, the bilge water accumulated at sea or in remote ports still poses a disposal problem. Coast Guard ships, for instance, may spend long periods of time in coastal waters and are unable to pump bilges. Crew boats and supply boats have the same problem.
