The fight over a proposed expansion of a sand and gravel mine on Maury Island is threatening to hold up creation of a new state agency to lead the cleanup of Puget Sound.

As the end of this year's state legislative session approaches this weekend, Sen. Erik Poulsen, D-Seattle, has been making a last-ditch attempt to add restrictions on the mine into legislation creating the Puget Sound Partnership. He said he may try to add his amendment to the state budget instead.

"If we leave the session with a new Puget Sound Partnership organization but we can't save the crown jewel of central Puget Sound, then what's the point, really?" asked Poulsen, whose district includes Maury Island.

But the strategy is raising objections that it could upset a delicate compromise between business groups and environmentalists on the new Puget Sound agency.

The agency is considered a critical first step for Gov. Christine Gregoire to reach her goal of restoring the Sound by 2020. Late Thursday the governor called Poulsen in to meet with her.

"It would take away our support" if Maury Island mine restrictions were added to the Partnership bill, said Grant Nelson of the Association of Washington Business. "We'd be then opposed to the Puget Sound Partnership legislation, which we have worked extremely hard to get passed."

And House Majority Leader Lynn Kessler, D-Hoquiam, said Maury Island doesn't belong in the budget, either.

"I do not want to start taking bills that fail and start putting them into the budget," she said.

Poulsen, whose district includes Maury Island, sponsored a bill earlier in the session to block mine expansion by prohibiting industrial activity in state aquatic reserves. The bill passed the Senate but didn't get a vote in the House.

This is the first year the Maury Island mine has emerged as an issue in Olympia, though environmentalists and island residents have been trying to block it for years.

Glacier Northwest, the mine's owner, wants to significantly ramp up gravel and sand extraction there and build a large new dock through a state aquatic reserve to load barges. The company says its plan is environmentally sound and has moved ahead despite criticism that it would threaten habitat and endangered orcas.

Poulsen said late Thursday that he didn't know yet whether he'll have the votes to tack on the amendment.

His proposal has revived hopes of some environmentalists who wanted both Maury Island protections and the broader Puget Sound bill. Still, Clifford Traisman, a lead environmental lobbyist, said Poulsen's effort is a long shot.

"If he can pull it off, he'll be the legislator of the decade," he said.

Warren Cornwall: 206-464-2311 or wcornwall@seattletimes.com