46 CFR 153.470 – System for discharge of NLS residue to the sea: Categories A, B, C, and D
Unless waived under § 153.491, each ship that discharges Category A, B, or C NLS residue, or Category D NLS residue not diluted to
(a) Minimum diameter of an NLS residue discharge outlet. The outlet of each NLS residue discharge system must have a diameter at least as great as that given by the following formula:
(b) Location of an NLS residue discharge outlet. Each NLS residue discharge outlet must be located—
(1) At the turn of the bilge beneath the cargo area; and
(2) Where the discharge from the outlet is not drawn into the ship’s seawater intakes.
(c) Location of dual NLS residue discharge outlets. If the value of 6.45 for K is used in § 153.1126(b)(2), the NLS residue discharge system must have two outlets located on opposite sides of the ship.