After Methane Leaks, DEQ Seeks Public Input on Drone Monitoring at Coffin Butte

Background on Methane Leaks at Coffin Butte Landfill

The Coffin Butte Landfill, an 178-acre facility located north of Corvallis, plays a critical role in waste management for Oregon. It handles nearly a third of the state's trash, including all of Polk County and most of Marion County. The landfill is owned by Republic Services, a major player in the waste management industry based in Phoenix, Arizona.

In 2022, the U.S. Environmental Protection Agency (EPA) identified significant methane leaks at the site, with some readings reaching potentially explosive levels. These findings revealed that the landfill was emitting methane at levels exceeding both state and federal limits, as well as what had been publicly reported. The situation worsened in 2024 when EPA investigators discovered over 40 locations where methane levels exceeded permissible thresholds, including holes in the landfill's cover material.

Regulatory Response and Proposed Rules

In response to these alarming conditions, the Oregon Legislature passed Senate Bill 726 in 2025, mandating that the owners of Coffin Butte adopt advanced technology to detect and address methane leaks. The Oregon Department of Environmental Quality (DEQ) has now proposed specific rules to implement this legislation, seeking public input on the measures.

The DEQ’s proposal focuses on using drone monitoring, which is currently the only method approved by the EPA for such purposes. This approach would replace the existing requirement for landfill staff to walk the surface with handheld methane monitoring devices. Other methods, like planes or satellites, would be used in addition to this requirement.

Cost and Controversy

Sniffer Robotics, a Michigan-based company, is the sole provider of drone monitoring services for landfills. According to officials from the company, the annual cost for drone monitoring at Coffin Butte would be approximately $76,000, with four visits per year and additional remonitoring if leaks are detected. In comparison, the landfill currently spends about $100,000 annually on handheld monitoring.

Despite potential cost savings, there is pushback from some stakeholders. Chad Darby, who works for Portland-based Maul Foster & Alongi, expressed concerns about the legislation favoring one landfill over others. “I really don’t like legislation that picks winners and losers,” he said during a rulemaking committee meeting. He questioned why other landfills weren't required to use the same technology.

Legislative Intent and Flexibility

Sen. Sara Gelser Blouin, the bill’s sponsor, emphasized that the focus on Coffin Butte was due to its ongoing methane emission issues, which have significantly impacted the health of local residents. She defended the legislation as a necessary step to improve safety and monitoring standards.

While the proposed rules specifically target Coffin Butte, they also allow other Oregon landfills to voluntarily adopt drone monitoring. However, some representatives have raised concerns about the reliance on a single service provider. Paul Koster, environmental services manager for Republic Services’ Oregon properties, questioned what would happen if Sniffer Robotics became unavailable.

In response, the DEQ included a provision allowing landfill operators to request approval for alternative technologies on a case-by-case basis.

Public Comment and Next Steps

The DEQ is accepting written comments on the proposed methane monitoring rules until 4 p.m. on June 1. Comments can be submitted via email at AQRules.2026@DEQ.oregon.gov or by postal mail to the Oregon DEQ. A virtual public hearing will take place on May 29 at 5:15 p.m. More information can be found on the DEQ website.

The proposed rules are set to go into effect on January 1, 2027. Additionally, the DEQ is seeking public feedback on a revised air quality permit for the landfill, with the comment deadline extended to 5 p.m. on May 29.

The state Land Use Board of Appeals is also considering whether to overturn Benton County Commissioners' decision to reject Republic Services’ application to expand the landfill.