A group of Bellevue community leaders that includes a former mayor and the Kemper Development Company is asking the Washington State Shorelines Hearings Board to vacate permits issued to Sound Transit for constructing a portion of its light rail line and transit station in the Mercer Slough Nature Park.

In their 89-page petition to the state shorelines board, the group argues Sound Transit’s plans for East Link along Bellevue Way and the west portion of the slough will cause permanent environmental impacts to the nature park. The petitioners further claim the Bellevue City Council was not aware of the impacts when it signed a memorandum of understanding with Sound Transit for the project. The memorandum was the basis for approving a shoreline development permit and variance for the project, the group claims.

Former mayor and councilmember Don Davidson said he’d opposed the MOU with Sound Transit while on the council because he felt there were questions that had gone unanswered by the agency through its final environmental impact statement, a number of which are either just now becoming apparent or remain undecided.

“It just wasn’t accurate,” said Davidson, “and now we’re coming back and saying, ‘Wait a minute, it’s time for someone to take another look at this.’ “

Davidson is joined in the petition by the Kemper Development Company, Geoffrey Bidwell — founder of the Save the Mercer Slough Committee — and nonprofit Building a Better Bellevue. A longtime advocate for motorists, Kemper Freeman Jr. lost a lawsuit in 2013 that sought to prevent Sound Transit from constructing light rail on I-90, arguing the interstate was paid for with gas taxes to support motor vehicles. A spokeswoman with Kemper Development said Freeman would not be commenting on the petition as of press time.

“There’s always a conversation and interested parties getting together,” Davidson said of the group, adding petitioners have no ulterior motive and are not trying to stop light rail from coming to Bellevue. “Kemper (Freeman) cares deeply about this city and certainly about the environment and transportation.”

Petitioners are asking that the state shorelines hearing board pull Sound Transit’s shoreline development permit and variance, and require the city evaluate the full impacts of the project and assess the feasibility of other options.

“It starts a process where we get to present our arguments orally,” said Virginia Nicholson with Schwabe, Williamson & Wyatt, the law firm representing the group. “That will probably happen in April. Both sides will be able to make their case.”

Nicholson said the hearing board will have 60 days to issue a decision after both sides make their case, part of that occurring on-site at the nature park.

In a statement, Sound Transit reports it is reviewing the appeal and will work with the state shorelines hearing board to address the matter.

“Our work so far to examine and address project impacts has been a long, careful and deliberative process to meet all environmental laws,” according to the statement. “We are confident we will be able to maintain our schedule to start major civil work in 2016 and carry riders in 2023.”

The petition states a noise wall, as well as an entrenched rail line to the south and north of the Winters House, will virtually block all visual and physical access to the west side of the nature park. Plans for an elevated guide rail near the old house, which is on the National Register of Historic Places, would also violate a mandate that the Winters House demonstrate the cultural history of the slough, the petition states.

The six to seven years it is anticipated to take to complete the transit station, including replacing the South Bellevue Park and Ride, also will have an impact on wildlife within the nature park, according to the petition, which adds that the Sound Transit plan includes removing 1,200 trees the council had not been aware of at the time the MOU was signed.

“I just think there’s a better answer than impacting the environment like they would,” Davidson said.

A lack of mitigative actions listed in Sound Transit’s environmental impact statement for handling restricted traffic capacity on Bellevue Way Southeast during station and rail line construction and its effect on traffic downtown is also cited in the petition.

Nicholson said the petition also seeks to verify whether Sound Transit plans to eventually tie light rail to Issaquah through the nature park, adding that should require the agency to assess the total environmental impact to the slough.