Archaeological commission waives pre‑construction survey for Fort Bragg ADU, requires tribal monitoring during all ground disturbance

The Mendocino County Archaeological Commission voted 4–0 on Jan. 8, 2025, to not require a full archaeological survey for CDP 2024‑0017, an after‑the‑fact conversion of a garage into a 1,200‑square‑foot accessory dwelling unit at 30320 North Highway 1, Fort Bragg, and instead to require tribal monitoring during all ground disturbance.

The commission’s decision follows a staff presentation by Russell Ford, staff planner for Mendocino County Planning and Building, and discussion with the applicant’s agent Masha (Masha Gromman), and consulting biologist Sarah Bradley of Dark Gulch Environmental Consulting. Ford described the proposal and noted prior Northwest Information Center (NWIC) comments recommending an archaeological survey; Bradley told commissioners the disturbed character of the area. “This area that’s being impacted by the leach lines is already highly disturbed,” Bradley said, adding that the biological survey she performed “did not find any shell middens or anything that would lead me to believe that this was an issue.”

Commissioners discussed whether a full survey or only monitoring was appropriate. Commissioner Cole and other commissioners noted the site is on a bluff and that much of the immediate work follows existing disturbed areas, including trenching for new septic pump and two leach lines. After debate, one commissioner moved “to not require a survey, but require tribal monitoring during all ground disturbance,” and another commissioner seconded the motion. The roll call vote was unanimous: Commissioner Cole — yes; Commissioner (unnamed) — yes; Commissioner Johnson — yes; staff — yes.

The commission document packet includes an engineering plan showing the existing septic tank and proposed abandonment of an older leach line in favor of two new leach lines to move the leach field away from the bluff. The applicant’s agent said installation work largely follows the existing driveway alignment and areas that are “pretty much disturbed, it’s all mowed and currently manicured.” Commissioners limited monitoring to ground‑disturbing activities (trenching, pump‑tank excavation and related work) rather than requiring a pre‑construction survey.

The commission’s action replaces a survey requirement that NWIC had recommended in its referral and instead requires on‑site tribal monitoring during any excavation or other subsurface disturbance. The motion’s conditions also indicated the monitoring requirement applies to “any ground disturbance,” which commissioners clarified includes trenching for leach lines and pump‑tank excavation.

No additional mitigation or engineering conditions beyond the tribal monitoring requirement were added by the commission; the applicant will proceed with the CDP process subject to that condition.

Votes at the meeting show the commission accepts monitoring in lieu of a survey in cases where biological or prior fieldwork indicates the disturbed character of the proposed ground‑disturbing area, while reserving the right to require a survey if circumstances change.

The county planner said applicants or agents should send any site photographs to the county before 2 p.m. on Jan. 8, 2025, for the record.