ANNAPOLIS, Md. — A conservation group announced Monday that it’s preparing to sue the Environmental Protection Agency for failing to enforce the Clean Water Act relating to pollution limits for the Chesapeake Bay.

The Chesapeake Bay Foundation announced it is preparing a notice of intent to sue the EPA, saying the agency has failed to take action for what the foundation is describing as an inadequate pollution reduction plan from Pennsylvania.

“That EPA is abdicating its responsibility under the Clean Water Act is a tragedy,” said Will Baker, the president of the foundation. “Failing to hold Pennsylvania accountable undermines the success we have seen in recent years. It is snatching defeat from the jaws of victory.”

The foundation says Pennsylvania’s proposal to reduce nitrogen pollution between now and a 2025 deadline has a funding shortfall of more than $300 million annually and the plan still falls 25% short of the nitrogen goal.

The EPA and Pennsylvania did not immediately comment on the announcement.

The foundation is highlighting comments made by Dana Aunkst, the director of the EPA’s Chesapeake Bay Program, for saying recently that the goals were aspirational and not legally enforceable.

“We are currently in discussion with a range of potential partners concerning the legal strategies we can use to force EPA to comply with the law,” said Jon Mueller, CBF’s vice president for litigation.

CBF points out that the group sued the EPA in 2009 for failing to enforce the Clean Water Act in the Chesapeake Bay region, prompting a yearlong negotiation between the group and the EPA.

That resulted in the EPA developing a limit on the amount of pollution the bay can withstand and remain healthy, and CBF agreed to drop the lawsuit.

The Chesapeake Clean Water Blueprint was created with the goal of having programs in place by 2025 to restore the bay. States in the bay’s watershed, the District of Columbia and the EPA endorsed the pollution reductions, and each jurisdiction pledged to reduce its share of nitrogen, phosphorus and sediment pollution, the foundation noted in its announcement Monday.