Ventura approves $5.5M sewer repair contract featuring onsite gasoline plume treatment

Ventura approves $5.5M sewer repair contract featuring onsite gasoline plume treatmentTo bypass the costly hauling of contaminated groundwater, Ventura has authorized a negotiated procurement approach using a mobile treatment plant to facilitate pipe bursting operations on a compromised sewer line.

The Ventura City Council approved a $5.5 million contract increase with Sam Hill and Sons, Inc. for the Monmouth Way sewer line repair, alongside a $164,848 construction management agreement with HDR Engineering, Inc.

The project will replace 335 linear feet of sewer line compromised by a 2024 gas station spill, utilizing pipe bursting to avoid a 400-foot open-cut trench.

High groundwater levels intersecting with the gasoline plume require continuous construction dewatering; the city will deploy a mobile onsite treatment plant to treat the water before discharging it into the sewer.

Operations will run in 24-hour shifts to minimize the duration of temporary dewatering, with continuous air monitoring for gasoline vapors.

The City of Ventura, California, has approved a $5.5 million contract amendment with Sam Hill and Sons, Inc. to repair a critical sewer line compromised by a gasoline spill, utilizing specialized dewatering and pipe bursting techniques. The May 19, 2026, decision resolves a complex infrastructure challenge that previously stalled during the public bidding process. In September 2024, a gasoline plume from a nearby Sinclair gas station compromised 335 linear feet of sewer line along Monmouth Way. The city has relied on a temporary mechanical bypass system since the incident. Initial bids to replace the pipe in October 2025 were deemed non-responsive because contractors planned to store and haul the contaminated groundwater off-site for hazardous waste disposal—an approach staff described as highly costly and logistically intensive. Following council authorization for a negotiated procurement process, the city developed an alternative approach. The project will now feature a mobile onsite water treatment plant to handle the contaminated groundwater. According to Senior Civil Engineer Elaine Camia, the system will treat the dewatered effluent to zero parts per million of hydrocarbons, verified by hourly spectrometer testing, before safely discharging it into the municipal sewer system. Because groundwater in the area sits roughly four feet below the street surface and the sewer line is buried at seven feet, maintaining a dry environment for the pipe bursting operation is critical. The contractor will work in continuous 24-hour shifts to minimize the time required to operate the pumping equipment. "The groundwater treatment will remove the gasoline, but it is possible that some of the vapors may escape," Camia noted during the meeting. To mitigate health risks, the city is coordinating with the Ventura County Air Pollution Control District and specialized subcontractors to continuously monitor air quality. Staff noted that steel plating is prepared for immediate deployment to halt work and seal the site if hazardous vapors are detected. The new sewer pipe will be installed using pipe bursting, pulling the new line through the existing one from designated entry and exit pits, which avoids nearly 400 feet of open-cut trenching. The replacement pipe is specifically designed to be resistant to gasoline solvents. In addition to the construction contract, the council approved a $164,848 professional services agreement with HDR Engineering, Inc. for construction management and observation. The repair work is slated to begin in mid-June and conclude in late July, though officials cautioned that the volatile nature of the groundwater could alter the timeline.