Sudbury town officials were thrilled last year when they finalized a deal to sell the former Melone gravel mine for redevelopment into much-needed housing, in exchange for 40 acres of land in the town's center.

The 36-acre property, which straddles the Concord-Sudbury line off of Route 117, was the site of the Melone sand and gravel quarry, owned and managed by the town of Sudbury since the 1990s. When the quarry was exhausted of its resources, the town began studying ways to redevelop the property that would benefit residents the most.

In 2018, the town of Sudbury issued an RFP and selected a proposal from Quarry North Road LLC to build Cold Brook Crossing, a 274-unit project that will include a mix of apartments, condos and townhomes — some of which are designated affordable or age-restricted.

Cold Brook Crossing is Sudbury's first project under Chapter 40R — which encourages smart growth with denser development — and will help the town maintain the state-mandated 10% affordable housing stock through 2030. 

The development is already leasing units and construction is expected to be complete this fall. 

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Now Quarry North LLC is looking to expand the development onto the Concord side of the property. In June, the developer submitted plans to build four single-family homes and one duplex on the 16-acre lot, half of which has already been mined and stripped of vegetation. 

But the site has its challenges. It's "landlocked" within the town of Concord, with access only from Route 117 within the town of Sudbury. There are currently no town utilities in that area, so Concord Power and Light would have to extend electric service there at the expense of the developer. The project is expected to have water service from Sudbury, through an intermunicipal agreement. 

Another issue is the wetlands on the site. Quarry North calls the project  "Rookery Lane," because of the great blue heron nesting site in the wetlands there, which the developer says will be preserved. 

Concord's Natural Resource Director, Delia Kaye, has recommended the open space be put into a conservation restriction, although the heron population there has dwindled in recent years, she said. 

Part of the development falls within the 100-foot buffer zone for those wetlands. That proximity is causing concerns for the White Pond Advisory Committee and the Friends of White Pond, two groups who advocate for the pond's preservation. The wetlands neighboring Rookery Lane feed into White Pond to the north of the project. 

The committee has been vocal in recent years about preserving the water quality of their beloved kettle pond, after harmful cyanobacteria blooms closed the pond to swimming for much of last summer.

The committee's research and consultation with environmental scientists shows cyanobacteria blooms are caused by excess nutrients, which often run off from human activity. Specifically, the committee believes that septic tanks around White Pond are a major cause of excess nutrients and cyanobacteria blooms.

Now the group is urging the town to require the Rookery Lane developer to find a different option than traditional septic tanks.

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"Other Massachusetts communities have identified sewage treatment as a primary contributor to toxic algae blooms in pond water," the committee wrote in a letter to Town Planner Elizabeth Hughes. "The White Pond Advisory Committee has spoken with dozens of state and New England pond experts to validate these results and its Sewage Subcommittee has confirmed that septic tanks are a primary source of damaging nutrients to White Pond. The White Pond Advisory Committee presented to the Town of Concord Select Board on November 8, 2021 with its identification of septic systems as a primary concern for White Pond."

The committee recommended the town either require Rookery Lane be connected to the Cold Brook Crossing sewage treatment, install upgraded septic tanks that filter out excess nutrients, or have the developer contribute to the creation of a sewer system at White Pond, which this project would connect to.

"The Town of Concord Comprehensive Wastewater Management Plan of Aug. 21, 2000 recognized the need for sewer treatment in the White Pond area. No action has been taken since due to a combination of finances and resources. While a financial and land contribution will not create a local sewage treatment plan on its own, this could go a long way towards jump-starting a solution to a long-standing problem of neighborhood-wide septic run-off to the pond," they wrote.

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Concord's White Pond municipal well is to the north of the site, which is also causing concerns among residents. In a recent Natural Resources Commission Meeting, Quarry Road North legal representative Bill Henchy said wastewater from the project is not expected to reach the well. 

"The proposal here is entirely outside of that zone two, so none of the wastewater here, in any respect, will travel toward the White Pond well," Henchy said.

Other residents wrote in with concerns about the developer's request for special permit to get around the maximum building height of 35 feet. The developer states that the land is artificially low due to being mined, so the homes will not appear too tall.

"Currently, it is a beautiful area enjoyed by wildlife and hikers. It would be terrible to destroy this area with views of homes, where now only open space is present," Jeff Parker wrote.

The project was originally expected to come before the Concord Zoning Board of Appeals on Sept. 8, but the developer has requested a continuance to the Oct. 13 meeting. Please check back for updates.