Section 30(2) in The Merchant Shipping (Prevention of Pollution by Oil from Ships) Rules, 2010
(2)In every oil tanker of one hundred and fifty gross tonnage and above, pipelines for the discharge to the sea of ballast or oil-contaminated water from cargo tank areas which may be permitted under rule 34 shall be led to the open deck or to the ship's side above the waterline in the deepest ballast condition and different piping arrangements to permit operation in the manner specified in clauses (a) to (e) of sub-rule (6), may be accepted.
