Residents warn of sinkhole, groundwater risk if Gilbert Farm CAFO expands

Multiple residents told the Door County Board of Supervisors they are worried a proposed expansion at Gilbert Farm and a separate CAFO permit on Matthew Road could threaten groundwater because of nearby sinkholes and thin soils.

Annette Vincent said work by soil-and-water experts and conversations with the DNR identified a sinkhole in a closed depression close to production facilities on the Matthew Road site. She warned a containment breach could channel liquid manure into the sinkhole and into the aquifer, recalled past contamination incidents and noted monitoring wells recommended by the hydrogeologist are not required until 2029.

Rod Miller, who lives about a mile from the Gilbert Farm production area, said the hydrologist report highlighted very shallow soils over Silurian dolomite that is "karstified" and that the sinkhole appears on Door County GIS maps. Miller said an 8,000,000-gallon liquid manure storage facility was proposed to accommodate the expansion to 2,430 animal units and argued that any approval should mandate redundant safeguards. "If this expansion is approved, we request, as a minimum, that all necessary redundant safeguards must be mandated by the appropriate regulatory body, and must be implemented by Gilbert Farms," Miller said.

Both speakers urged the board to consider local regulatory options in addition to DNR permitting, suggesting fire-response plans, carcass and infectious-disease plans and financial bonds to secure cleanup in the event of a catastrophic containment failure. The board received the comments during public input; no formal board action on the CAFO permits was recorded at this meeting and staff referred to an upcoming public hearing scheduled for Nov. 5 at 10 a.m. in Sturgeon Bay (Vincent said no official notice had been sent yet).