BANGOR – Two of Maine’s largest environmental organizations formally stepped up their opposition campaigns Monday against Plum Creek’s development plan for the Moosehead Lake region.

Maine Audubon and the Natural Resources Council of Maine filed for intervenor status on Plum Creek Timber Co.’s 408,000-acre rezoning petition pending with the state’s Land Use Regulation Commission.

During events held Monday in Bangor and Portland, representatives of the two organizations said that Plum Creek’s latest revisions to the development plan were steps in the right direction. But the groups’ leaders said it would be “undeniably irresponsible” to embrace a plan they believe will harm wildlife populations and the region’s natural character.

“LURC and Maine people have only one opportunity to get it right,” Brownie Carson, NRCM’s executive director, said during a Bangor press conference. “Seattle-based Plum Creek will come and go, but the people of Maine will live with the decisions that we make and that LURC makes … forever.”

A Plum Creek official defended the company’s plan as offering an unprecedented amount of forestland conservation and economic development. Luke Muzzy, land asset manager for Plum Creek, said the company made significant changes in response to feedback.

“When we did this plan, we knew it wouldn’t make everybody happy,” Muzzy said. “We were hoping they would see the changes we’ve made during the past two years because many of these changes are things that they suggested.”

Groups and individuals have until Wednesday to file with LURC for intervenor status on Plum Creek’s lake concept plan. Although anyone will be entitled to speak during public hearings, tentatively scheduled for November, intervening parties can enter evidence and cross-examine other parties during official proceedings.

Plum Creek first unveiled its historic development plan for the Moosehead region in April 2005. The proposal has sparked heated debate both in the Moosehead region and statewide over how to rejuvenate struggling North Woods communities without sacrificing the region’s natural beauty.

The company’s current plan, which is the largest development ever proposed in Maine, calls for 975 house lots in more than a half-dozen locations near Moosehead Lake. Plum Creek has also proposed an 800-accommodation resort on Big Moose Mountain and a 250-accommodation resort on Lily Bay.

Plum Creek managed to gain additional public support by offering to permanently place more than 400,000 acres off-limits to development. The company would donate 90,000 of those acres but would receive compensation for the remaining conservation acreage under a separate deal.

Plum Creek has said the latter conservation deal – negotiated with The Nature Conservancy, Appalachian Mountain Club and the Forest Society of Maine – is contingent on LURC approval of its Moosehead Lake concept plan.

Maine Audubon executive director Kevin Carley complimented Plum Creek for reducing the amount of shorefront lots from earlier plans and removing some development from outlying water bodies. But the current plan still poses an unacceptably high threat to wildlife, he said.

Carley predicted the development would destroy habitat, disrupt wildlife travel corridors, increase siltation in lakes and streams, and lead to more vehicle accidents involving wildlife. He singled out the threatened Canada lynx as one species that would be particularly affected by the plan.

“There is a way for Plum Creek to do this right,” Carley said. “This plan is not the way.”

Carson and other NRCM representatives said the resorts are too large and that the rest of the plan contains too much development in inappropriate places. They also criticized Plum Creek’s linkage of the privately negotiated conservation deal with the development plan as well as aspects of the conservation easements.

Representatives of both groups said they are taking their roles as intervenors very seriously given the Moosehead region’s significance to Maine people and the state’s economy.

“We will remain opposed unless Plum Creek fixes the problems we have identified here today,” Carson said.

Muzzy said that Plum Creek is not interested in reducing the number of house lots or accommodations, adding “these are the numbers we need” to make the plan work financially.

Muzzy also pointed out that both Sugarloaf/USA and Sunday River ski resorts have more accommodations than proposed at Big Moose Mountain but without the conservation. He said the company is concerned about impacts on wildlife and will work with LURC should issues arise.

Overall, the concept plan is the best option because it offers planned growth, Muzzy said.

“Development is happening up here anyhow and it’s not tied to the conservation that we have” in the company’s plan, he said.

For more information on Plum Creek’s plan, go to www.maine.gov/doc/lurc