33 CFR 151.79: Operating requirements: Discharge of sewage within Antarctica.

(a) A vessel certified to carry more than 10 persons must not discharge untreated sewage into the sea within 12 nautical miles of Antarctic land or ice shelves; beyond such distance, sewage stored in a holding tank must not be discharged instantaneously but at a moderate rate and, where practicable, while the ship is en route at a speed of no less than 4 knots. For purposes of this section, “sewage” means:

(1) Drainage and other wastes from any form of toilets, urinals, and WC scuppers;

(2) Drainage from medical premises (dispensary, sick bay, etc.) via wash basins, wash tubs, and scuppers located in such premises;

(3) Drainage from spaces containing living animals; or

(4) Other waste waters when mixed with the drainages defined above.

(b) Paragraph (a) of this section does not apply to a warship, naval auxiliary, or other ship owned or operated by the United States and used only in government non-commercial service.

(c) Paragraph (a) of this section does not apply in cases of an emergency relating to the safety of a ship and those on board or saving life at sea. Notice of an activity, otherwise prohibited under paragraph (a) of this section, undertaken in case of an emergency shall be reported immediately to the National Response Center (NRC) toll free telephone number: 800-424-8802, direct telephone: 202-267-2675, or Fax: 202-267-1322.