PORTLAND — Consultants have recommended a controversial Brunswick site for a proposed $5 million layover facility for The Downeaster trains when rail service is extended northward late next year.

The Northern New England Passenger Rail Authority announced the recommendation of the “Brunswick West” site late this morning at a news conference in Portland, but said it will listen to neighbors’ concerns at a meeting in Brunswick Thursday night. The final decision is in the hands of the NNEPRA board, which is scheduled to meet Monday and could vote at that time.

The site has been opposed by neighbors, particularly those on Bouchard Drive, where houses are as close as 240 feet to the facility.

The layover facility will hold up to three trains at a time. Trains will pull into the facility after their last run of the day, probably after midnight, where they will be cleaned and minor servicing will be performed. The trains will start up again in the early morning and will idle for about a half-hour while safety checks are performed and the trains warm up.

NNEPRA wants to construct the new layover facility for use after rail service is expanded north to Freeport and Brunswick. The Downeaster trains, which currently run between Portland and Boston, now spend nights outdoors in Portland.

The consulting firm, Parsons Brinckerhoff, said the Brunswick West location is the site of a freight railyard which NNEPRA is in the process of buying. Jan Okolowicz, the project manager for the consultants, said tests indicated there would be no impact on air quality from the diesel locomotives. He said concerns over problems caused by vibrations from the trains and noise could be mitigated by insulating the layover building.

He said the main noise concern would be two short blasts to test the trains’ horns at the end and the beginning of the day, but that engineers were looking at ways to minimize the noise exposure to the neighborhood. The blasts would be two to three seconds long, between 2 a.m. and 4 a.m., and are required by federal safety rules, said Patricia Quinn, NNEPRA’s executive director.

Two other sites were rejected by the consultants. There were concerns over costs at one site, near the Brunswick Industrial Park, because the authority would have to buy six parcels from five different owners to put together the land needed for the facility.

Another site, near Cooks Corner, was deemed too far from the Brunswick Rail Station. Okolowicz said it would take as long as 45 minutes, each way, to move the trains to and from the station to the layover facility.

The public meeting on the recommendation will be at 6:30 p.m. Thursday at the Brunswick Council Chambers at Maine Street Station, 16 Station Ave.