33 CFR § 157.43 - Discharges of clean and segregated ballast: Seagoing tank vessels of 150 gross tons or more.
(a) Clean ballast may not be discharged overboard unless the discharge is verified as clean ballast through use of an approved oil discharge monitoring and control system or, if discharged before the required oil discharge monitoring and control system installation date, by visual examination of the ballast contents immediately before discharge. This paragraph applies to discharges of clean ballast:
(1) From dedicated clean ballast tanks; and
(b) Segregated ballast may not be discharged overboard unless a visual examination, or a test of the ballast contents with an oil/water interface detector, immediately before the discharge shows that there is no oily mixture in the ballast. Use of an oil discharge monitoring and control system is not required. This paragraph applies to discharges of segregated ballast:
(1) Into the navigable waters of the United States; and
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