Unexpected septic tank found at foundation; administration seeks change orders within contingency

During construction at a township site an excavation crew uncovered a previously unknown septic tank described as roughly 5 by 5 feet. The administrator said engineers and environmental consultants inspected the tank, found it intact and containing septic contents, and recommended removal.

The administration authorized a first change order of about $6,700 to remove the tank and procured a not-to-exceed proposal of approximately $17,250 from the contractor for additional exploratory excavation and work that may be necessary. An on-site inspector from Beckmeyer Engineering will oversee the work. Staff said the costs are within the project's contingency and that formal paperwork for the change orders will be presented to the council at the May 18 meeting for ratification.

The administrator said the finding was not foreseeable from prior remediation work and that records predating the installation of sewers (pre-1970) often include filled or incorrectly abandoned tanks. Council members discussed potential recourse with vendors and engineers but staff said the tank discovery appears to be a legacy condition and must be addressed to proceed with foundation work.

Next steps: staff will bring formal change-order documentation to the May 18 meeting for council approval and will continue on-site inspection during removal operations.