The garbage buried at the San Joaquin County landfill on North Austin Road — including that from Manteca, Ripon, and Lathrop — will help supply gas to 8,400 households served by PG&E.

The San Joaquin County Board of Supervisors on Tuesday are expected to approve an easement to allow Ameresco to construct a renewable natural gas compressor station on undeveloped Stockton Metro Airport property.

Once the station is completed, PG&E will sublease the facility that will be used to mix the treated menthane gas taken from the Forward Landfill north of French Camp Road and processed to the quality level needed for domestic use.

Currently, methane gas from the Forward Landfill runs Ameresco’s Landfill Gas to Energy Plant at the northeast edge of the landfill property, with excess gas being burned at a flare station adjacent to that plant.

 In order for PG&E to accept the landfill gas, it must be conditioned — contaminants and impurities removed — to meet PG&E’s Rule 21 renewable natural gas quality requirements.

The existing plant’s enclosed flares would continue to be the primary control devices for the landfill, but would not operate when the facilities supplying the PG&E system are operating except to burn excess methane gas beyond what can be processed.

A new pipeline from the landfill site will be extended to the airport property where the compressor station will be located. Once there, it will be combined with natural gas in the PG&E system.

The Forward Landfill has more than 200 methane wells.

The methane is used to create renewable natural gas that is purified biogas from decomposing organic matter such as food scraps, landfill waste, or manure that's cleaned to be chemically identical to conventional natural gas.

That allows it to be used in existing pipelines for power, heat, or vehicle fuel, and significantly reduce methane emissions.

It's a sustainable, on-demand energy source that offers environmental benefits by capturing potent greenhouse gases before they escape.

The purified methane gas is injected into existing natural gas pipelines for distribution to homes and businesses.

Renewable natural gas from landfill waste is two to three times more energy-efficient than converting the same biogas into electricity.

To contact Dennis Wyatt, email dwyatt@mantecabulletin.com