Thousands of tons of soil must be removed and taken to another site in addition to some remediation at the site of a proposed five-story rental complex near Lot B on Main Street.

Redevelopment Director Peter Pelissier told the Redevelopment Agency earlier this month that he met with Nils Berten of Slokker Real Estate Group and that an extension of the redevelopment agreement is needed after receiving environmental reports. Commissioners extended the redevelopment agreement for another 120 days at its May 1 meeting.

For the two levels of parking that are planned, Pelissier said, about 6 feet of dirt must be excavated. Berten advised him that 20,000 tons of “historical fill”must be removed and taken to another site, which could cost $40 to $50 per ton, or some $800,000 to $1 million. Historical fill only means that it’s not “virgin earth,” and isn’t necessarily contaminated but could have anything in it, he said. At one time it was a marshy area before fill was brought in while building elevated railroad.

Remediation and monitoring wells of soil where a gas station once stood on the corner of Poplar Street also could cost an estimated $250,000, Pelissier said.

Slokker is interested in the project and has hired an architect to further detail and design a concept plan that was presented to the Redevelopment Agency last year, he said. The firm also is negotiating with the Parking Authority for a land swap and additional parking, if necessary should there be any loss of parking spaces. “The good news is their marketing study finds that the rents and number of units proposed would work,” Pelissier said, and Slokker is pleased with the demographics.

Slokker Real Estate Group had partnered with Dornoch for the proposed Westbury project before the housing market crashed. In December, representatives from Slokker presented the Redevelopment Agency with a concept plan of about 180 rental units in two, five-story buildings with parking and about 4,500 square feet of retail space on the ground level. There are no immediate plans for an application to the Zoning or Planning boards.