The state Department of Conservation and Recreation plans to chase federal stimulus dollars to finish off the Neponset Greenway trail as the agency appears to have finalized a proposal extending the riverside path by one mile.

Department officials plan to unveil the proposed alignment of the extension at a public meeting at the Foley Senior Residences in Mattapan on Aug. 30. MBTA officials, who had raised safety concerns about the possibility of an at-grade crossing as part of the trail that could run through the Mattapan Square MBTA station, are also expected to attend.

At a Wednesday night meeting of the Neponset River Greenway Council, the agency’s project manager, Cathy Garnett, remained tight-lipped when questioned by council members about the extension's overall configuration.

The Reporter wrote earlier this year that a compromise, drawn from five alternatives the agency was weighing, had been developed. The compromise would have included parts of both Milton and Boston, with part of the trail on the Milton side at Central Ave. and then crossing the river near the Ryan playground and heading down the Mattapan side to the Mattapan Square T station.

The trail has drawn controversy from potential abutters, who in public meetings last year argued that several of the alternatives plans could involve the blasting of rocks near their homes and the destruction of trees.

“Things have changed with the design of the trail,” Garnett told the dozen or so council members who turned out Wednesday night.

She acknowledged a deal had been reached with the MBTA. The transit agency, which had cited federal safety regulations in raising safety concerns about an at-grade crossing, told the Reporter last week that it and DCR had discussed a number of solutions, and an at-grade crossing was back on the table, as were an overpass and an underground tunnel.

Rich Davey, the MBTA's general manager, told the Reporter on Thursday that "at this point" the agencies are looking at a "modest" pedestrian bridge over the trolley tracks. But, he added, "there’s a lot more community process to be had.”

The Aug. 30 community meeting will allow for public input on the final deal as DCR sprints to apply for a federal grant by October, Garnett said. She said community outcry over the final proposal could lead to agency losing out on the federal funding and again slowing down the project.

If DCR receives the $10 million grant, the agency would throw in $2.5 million. The funding would not just go towards extending the greenway by one mile. In total, roughly three “missing” miles would be added, bringing the trail’s total length to eight miles and having it run completely from the Blue Hills to Boston Harbor. Five miles already exist.

The federal funds will also pay for a trail to be built between the brightly colored gas tanks off of Morrissey Boulevard and the highway. The current owner of the gas tank, National Grid, granted DCR an easement.

The trail will continue down to Tenean Beach and goes to Water St., and then along the edge of the former Shaffer Paper site in the Port Norfolk neighborhood, where it would connect with the already existing trail at Pope John Paul II Park.

Boston Natural Areas Network president Valerie Burns called the potential compromise “an exciting opportunity to really unite the different constituencies along the trail.”

“I think we’re all eager to see the resolution the MBTA and DCR have come up with,” she said.

EDITOR'S NOTE: This story was updated with MBTA GM Davey's comments on Friday afternoon.