Commissioners press applicant on log materials, lifespan and species protections

During the Mill River hearing, commissioners repeatedly pressed the applicant on lifecycle, sourcing and post-installation risks of the proposed log jams and root-wad benches. Questions included whether logs would be preservative-treated or permeated with arsenic, which tree species would be used, how durable the structures would be in aerobic vs. anaerobic conditions, and what contingency plans exist if structures fail and material moves downstream.

Joe Rogers said consultants favor species such as hemlock for longevity but that the intention is for logs to degrade over time and become part of the bank and habitat. "...they use things like hemlock...I know that hemlock came up a lot because of the fact because it can be long lived," Rogers said. He also said contractors and fluvial geomorphologists would determine final species and anchoring, and he offered to follow up with specifics on whether logs would be treated or how metal anchoring would behave as organic materials decompose.

Commissioners also asked about biological surveys and timing. Rogers cited a long-term mussel study by Ethan Nedeau and said the project includes mussel and turtle surveys, relocation plans if necessary, and seasonal constraints: "there's certain times of the year where you can't work because of the mussels...there's certain times of the year where the turtles are hibernating potentially in the bank." The commission requested the applicant return with clearer material-sourcing and treatment information at the continued hearing.