Plans to create yet another Kendall Square on the sea, this time in Dorchester, have moved ahead.

Developer Accordia Partners filed a letter of intent Thursday with the Boston Planning & Development Agency for a 5.9M SF mixed-use development spread across two properties, including the former Bayside Expo Center site where Accordia and partner Ares Management Corp. have a 99-year, $235M ground lease with UMass Boston. Accordia plans to build 3.5M SF on the Bayside property and 2.4M SF at 2 Morrissey Blvd., which the development partners bought for $110M last year.

"In filing our Letter of Intent for the Bayside site and an adjacent parcel, we are delighted to move forward with a proposal that will enhance the Columbia Point Peninsula, create a number of positive community benefits, fulfill several important University of Massachusetts goals and strive to achieve unparalleled levels of inclusion in jobs, housing, education and training,” Accordia Partners leaders Kirk Skyes and Richard Galvin said in a joint statement.

Accordia is proposing 1,740 residential units, more than 4M SF of “office, research and development, life sciences and/or academic uses” and more than 155K SF of retail and civic space. There are also nearly 14 acres of public open space proposed for the project.

The 2 Morrissey Blvd. property is currently leased to Santander Bank, and Accordia said in the LOI the site is “anticipated to be redeveloped in a later phase of the proposed project, after the existing tenant’s lease has expired.”

Santander’s lease ends at the end of June 2025, the Boston Business Journal reports. The bank isn’t expected to make an early exit.

“We have no plan at this time to relocate the approximately 2,300 workers there,” a Santander spokesperson told the BBJ.