A federal judge has allowed pipeline company Plains Southcap to intervene in a lawsuit between Mobile Baykeeper and the U.S. Army Corps of Engineers, citing a rule of civil procedure permitting non-parties to step in to protect interests “that may be impaired by the disposition of the suit,” particularly those which existing parties “cannot adequately protect.”

Plains’ interest, U.S. District Court Judge William Steele determined, is the $130 million it has invested in a near-completed 45-mile oil pipeline between north Mobile and Pascagoula. In intervening, the company argues it is entitled to do so as a right because “the principal object of the Complaint is to preclude Plains from completing construction of and thereafter operating its nearly completed Pipeline.”

Last month, the Southern Environmental Law Center filed the suit, acting on behalf of Mobile Baykeeper and alleging violations of the Clean Water Act and the Corps’ failure to follow proper procedure in permitting the pipeline.

According to Plains’ spokesperson Jon Gray, “While the lawsuit is against the Army Corps of Engineers, it is our pipeline and the lawsuit is attempting to invalidate the permit we received to construct it. We are intervened to protect our permit to construct the pipeline and appreciate the Court’s recognition of our legal right to do so.”

Indeed, Steele determined “it is difficult to imagine a scenario in which Plains Southcap could have a more direct interest in the subject matter of the litigation than it does here. The injunctive relief that Baykeeper seeks in this action would force Plains Southcap to cease its Pipeline construction activities, prevent it from completing the project, and deprive it of the ability to realize economic benefits from its enormous investment in the pipeline.”

Immediately after Steele’s ruling, Plains filed a 15-page response to the lawsuit, alleging the court has no jurisdiction over the suit and Baykeeeper has no standing to assert any of the claims made in the suit. The Corps of Engineers has yet to respond.

An attorney for the SELC litigating the case on behalf of Mobile Baykeeper did not immediately respond to a request for comment, but Plains’ motion for intervention was uncontested.