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Water: Uniform National Discharge Standards (UNDS)

Surface Vessel Bilgewater/Oil Water Separator

Note: The documents on this webpage were generated a number of years ago. Some of the documents and data within may have been succeeded by more recent efforts.

The surface vessel bilgewater/OWS discharge consists of a mixture of wastewater and leakage from a variety of sources that are allowed to drain to the lowest inner part of the hull, known as the bilge. The anticipated standard will require, where practicable, the collection and transfer of bilgewater for on-shore treatment. Where it is impracticable to collect and transfer bilgewater, the bilgewater must be processed through an oil water separator, and meet effluent limits, which may vary depending upon the type and age of the vessel.

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Nature of Discharge:
Summary (PDF) (2 pp, 11K) Exit EPA Disclaimer and full discussion (PDF) (28 pp, 356K)

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Draft Discharge Assessment Report (PDF) (90 pp, 1MB)

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Draft Characterization Analysis Report

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Draft Environmental Effects Analysis Report

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Draft Feasibility Impact Analysis Report



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