Wastewater ponds at a 40-year-old, city-owned wastewater treatment plant in Northern California were found to be leaking. There was concern the contaminated water, which had leaked into the groundwater, would impact a nearby river with untreated sewage. The California State regulatory agency had notified the city that fines would be assessed. An investigation to determine the cause of the leak at the wastewater treatment plant was needed.
WASTEWATER TREATMENT PLANT INVESTIGATION EXPERT SERVICES
Wastewater treatment plant investigation expert Steven P. Viani, PE, reviewed the original design, soils report and construction logs to determine what the original conditions were and what the scope of construction requirements would be. The wastewater treatment plant investigation uncovered that one of the ponds did not have the required liner and was in communication with the groundwater.
The city issued a bid and an unlicensed contractor was awarded the contract to remove the accumulated bio-solids from the leaking pond as a first step in the repair of the wastewater treatment facility. As part of the repair work, the contractor was required to protect the sides and bottom of the pond to prevent damage and exacerbate the communication issue with the groundwater. Unfortunately, the contractor did not protect the wastewater treatment plant pond during excavation.
Following completion of the removal, a clay liner was installed; however, the city allowed the pond to desiccate and crack. The effect significantly reduced effectiveness of the clay liner.
The repair costs incurred by the city were reviewed, and it was noted the city attempted to have the carrier reimburse them for the fine.
Based on Steve’s forensic investigation of the wastewater treatment plant, the city received reimbursement for the costs incurred, including investigation and construction, but not for the fine. Steve saved the insurance carrier approximately 20x his fee.