MBTA General Manager Phillip Eng said he welcomes discussions about re-casting the Red Line tunnel cap as an extension of the existing tunnel cap pathway from Melville Avenue to Shawmut Station and down to Centre Street.

“The MBTA welcomes ideas that explore the use of the T’s existing transit assets to improve the quality of life in the communities served by the MBTA,” Eng said through a spokesperson, and at an in-person meeting last month. “The T looks forward to reviewing the feasibility study upon its completion.”

The city has put out a Request for Proposals (RFP) for an engineering feasibility study to explore the structure of the tunnel cap to determine what will be possible, if anything, on top of the cap, which is currently fenced off and not in use from Shawmut to Ashmont, and from Fields Corner to Shawmut, and report back before June 30.

The T said that the main thing they will need to understand is the weight-carrying capacity of the tunnel roof, the presence of utilities, and impacts of any proposed plantings on the pathway.