Woburn commission issues Negative 3 RDA for homeowner’s geothermal system

Scott Hamilton, the property owner, told the Woburn Conservation Commission on Dec. 5 that he seeks a Request for Determination of Applicability (RDA) for a ground‑source geothermal system to replace his home’s oil heat. Hamilton said the plan calls for two boreholes in the front yard connected as a closed loop that will be buried about 4 to 5 feet and enter the house at the foundation.

The commission’s staff and members questioned details of the system during the public hearing, including whether an antifreeze mixture would be used and how the loop would be connected. Hamilton said any antifreeze would likely be a low‑level propylene glycol mixture and described the boreholes as having paired pipes joined by a U‑bend at the bottom; he added the system can provide both heating and cooling and estimated substantially higher heating efficiency than resistive heat.

After no members of the public requested to speak, a commissioner moved to close the public hearing and the board voted to do so. A subsequent motion requested the RDA be given a "Negative 3" determination, meaning the work is described as in the buffer zone and, in the commission’s finding, will not alter an area subject to jurisdiction under the Wetlands Protection Act and therefore does not require an Order of Conditions. The motion was seconded and approved by the commissioners present.

The commission’s action is procedural: it records the commission’s finding about applicability under local/state wetland rules and does not itself authorize construction beyond the RDA determination. Hamilton thanked the commission after the vote. The commission did not record any public objections during the hearing and asked staff and the applicant to remain in contact if follow‑up details are needed.