Town's Herring Pond alum retreatment drawn out as commission seeks more technical detail; matter continued to Nov. 10

Representatives from the Town and the Herring Pond Association (Hillary and volunteer Mickey Marcus) presented a multi‑document submission supporting a proposed alum retreatment of Herring Pond, where previous alum treatment occurred in 2012 and recent monitoring shows reduced clarity and elevated phosphorus. Materials included corrected WPA Form 3, December 2025 lab results, a treatment work plan from Solitude Lake Management, a Massachusetts Division of Marine Fisheries guidance document on timing/limits related to herring runs, and the state lake management guidance (2026).

Commissioners raised multiple technical and regulatory concerns: the filing relied in part on historical templates and state guidance but had not applied 310 CMR 10.534 (ecological restoration/limnology requirements) in a project‑specific way; Appendix A and direct referral comments from DMF (Division of Marine Fisheries) and MassWildlife (for trout stocking/herring runs) had not been received; the treatment area numbers were inconsistent (Form 3 references the full 44‑acre pond while the Solitude work plan described treatment of roughly 20 acres—the deeper areas the contractor can practically treat); sediment phosphorus trends and the basis for a proposed 75 grams per square meter dose required a limnologist's integrated analysis; and the mobilization/boat access plan and the licensing/permit sequence (town order of conditions followed by annual state license to apply) needed greater specificity. Commissioners also asked about alternatives (lanthanum clay products such as Phoslock) and why alum was preferred based on the most current data.

Town staff said Solitude would refine dosage based on the most current sediment and water data prior to application and that annual licenses and applicator plans would come back to the commission before any treatment. Commissioners concluded there are substantive gaps and requested the applicants submit the application package directly to DMF and MassWildlife for written comment, provide Appendix A and an applied 10.534 analysis, clarify the exact acreage proposed for treatment and dosing basis, and secure a limnologist's synthesis of sediment and water data. The commission voted to continue the matter to November 10 to allow time for agency responses and plan revisions.