((a)) ** Persons with adversely affected interests as plaintiffs; defendants** Except as provided in subsection (b) of this section, any person having an interest which is, or can be, adversely affected, may bring an action on his own behalf—

((1)) against any person alleged to be in violation of the provisions of this chapter, or regulations issued hereunder;

((2)) against the Secretary where there is alleged a failure of the Secretary to perform any act or duty under this chapter which is not discretionary with the Secretary;

((3)) against the Administrator where there is alleged a failure of the Administrator to perform any act or duty under this chapter which is not discretionary; or

((4)) against the Secretary of the Treasury where there is alleged a failure of the Secretary of the Treasury to take action under .

((b)) ** Commencement conditions** No action may be commenced under subsection (a) of this section—

((1)) prior to 60 days after the plaintiff has given notice, in writing and under oath, to the alleged violator, the Secretary concerned or the Administrator, and the Attorney General; or

((2)) if the Secretary or the Administrator has commenced enforcement or penalty action with respect to the alleged violation and is conducting such procedures diligently.

((c)) ** Venue** Any suit brought under this section shall be brought—

((1)) in a case concerning an onshore facility or port, in the United States district court for the judicial district where the onshore facility or port is located;

((2)) in a case concerning an offshore facility or offshore structure under the jurisdiction of the United States, in the United States district court for the judicial district nearest the offshore facility or offshore structure;

((3)) in a case concerning a ship, in the United States district court for any judicial district wherein the ship or its owner or operator may be found; or

((4)) in any case, in the District Court for the District of Columbia.

((d)) ** Costs; attorney fees; witness fees** The court, in issuing any final order in any action brought pursuant to this section, may award costs of litigation (including reasonable attorney and expert witness fees) to any party including the Federal Government.

((e)) ** Federal intervention** In any action brought under this section, if the Secretary or Attorney General are not parties of record, the United States, through the Attorney General, shall have the right to intervene.