Cowlitz County commissioners on Tuesday approved a $1,490,001.76 contract with Glacier Environmental Services to expand the gas collection and control system at the county headquarters landfill.

County Public Works Project Manager Sean Roe told the board the project includes installation of 20 vertical wells, about 18,000 feet of linear pipe and well depths that average about 110 feet. "This is a expansion to our gas collection system. It was for the installation of 20 vertical wells. An average depth on that is about a 110 feet with about 18,000 feet of linear pipe also being installed in here," Roe said.

The nut graf: County staff said the vertical-well system is intended to sustain long-term gas collection and keep the landfill in compliance with state environmental standards while preserving future options for energy recovery.

Roe and County Engineer Susan Eugenis described vertical wells as a longer-term approach than horizontal wells installed during cell construction, adding they are more robust as waste settles. "With the vertical wells, they drill a 3 foot hole, to the depth of that we need," Eugenis explained. She described a 6-inch perforated casing surrounded by gravel and said the landfill is kept under vacuum so gas is drawn to the collection system.

Roe told the board the county currently extracts about 1,000 cubic feet per minute (CFM) of landfill gas from the site and that the Tenant Way (older) site is flared at about 300 CFM. Roe said the improved system will produce a more consistent gas quality and be easier to manage if the county later pursues power generation or renewable natural gas options: "The gas quality that comes out would be...more consistent, and so it'd be easier to manage a, generator system or an RNG system in the future if needed." He also said the county's past analysis estimated an energy equivalence roughly in the range of powering 4,000 to 4,500 homes at current gas volumes, though officials cautioned volumes will change over time as waste decomposes.

Commissioners asked whether the contract covers only installation and whether monitoring and tuning would be performed by county staff; Roe said the bid award covers installation and piping only, and that landfill staff will operate and monitor wells and flares. Eugenis noted some wells will include leachate pumps.

A motion to award the bid to Glacier Environmental Services carried after the board called for a vote. The project is described by county staff as part of post-closure compliance and long-term landfill operations; commissioners and staff said the improvements are required by state environmental rules to continue operating the county landfill.

Ending: County staff said the system currently sends collected gas to two flares; if the county and local utilities later pursue energy capture, the vertical-well layout should ease future connections. Construction timing and funding details beyond the contract price were not specified at the meeting.