Operating restrictions.

(a) Each hopper dredge assigned a working freeboard may be operated at drafts from the normal freeboard to the working freeboard if the— (1) Seas are not more than 10 feet; (2) Winds are not more than 35 knots; (3) Area of operation is not more than 20 nautical miles (37 kilometers) from the mouth of a harbor of safe refuge; and (4) Specific gravity of the spoil carried is not more than the highest specific gravity of spoil used in the stability calculations required by subchapter S of this chapter. (b) The Assigning Authority designates on the face of the dredge's load line certificate— (1) Each restriction contained in paragraph (a)(1) through (a)(3) of this section; and (2) The maximum specific gravity of the spoils allowed to be carried.