ANR has sensors that monitor the gas quality as it enters the pipeline, so if the CNG doesn’t meet the quality standard, the valve to the pipeline will be shut.

The other particles removed from the gas are burned away and disposed of — a requirement from the Environmental Protection Agency — but the county hopes to find ways to harness the other compounds in the landfill’s gas, said John Welch, director of the county Department of Waste and Renewables. One potential option would be trapping the excess carbon dioxide and turning it into dry ice.

“Long term, our goal is to have zero emissions” from the landfill, Welch said.

The facility is expected to offset about 3 million gallons a year of gasoline that otherwise would have been used, Parisi said, and that number could grow to 4 million in future years. That would be like taking 4,800 cars off the road.

The facility itself isn’t running on green energy yet, but it will use power from a large solar panel array set to be installed at the Dane County Regional Airport once that project goes online.

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