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Circular File: A Lot of Hot Air

The reality of landfill gas recovery.

As I write this, 518 landfill gas-to-energy projects are operating in 46 states. EPA considers another 520 landfills to be good candidates to host these projects. Landfills produce gas as part of the ongoing process of decomposition of organic materials. The resulting gas is half methane and half carbon dioxide with traces (less than one percent) of non-methane organic compounds.

Methane is a greenhouse gas. It is more potent than carbon dioxide (by far the most prevalent greenhouse gas) though less potent than the other greenhouse gases. Landfills are the second-largest producer of human-related methane in this country, responsible for about 22 percent of these emissions. They are exceeded only by ruminant animals, such as cows, which produce methane as part of their digestive process (consider those emissions the next time you scarf down a hamburger).

Landfill gas can be flared off or converted into an energy product such as electricity or pipeline-quality gas. This medium-BTU gas can even be converted into a biofuel suitable for powering garbage trucks. BMW’s manufacturing plant in Spartanburg, S.C., the University of New Hampshire, and SC Johnson’s Waxdale, Wisc., facility are among the many users of energy produced at landfills.

These projects offer a host of benefits, such as converting greenhouse gas into a beneficial resource and reducing our reliance on fossil fuels. Nonetheless, the very existence of landfill gas recovery remains controversial, with many would-be debunkers arguing against the wisdom of converting this gas into energy.

In fact, when I read their various mythbusting attempts, I noticed that none of the existing projects were mentioned. Rather, the authors of these exposés go to great lengths to prove that landfill gas cannot be successfully or efficiently recovered. They insist that only “wet” landfills can generate and recover methane. However, they never define what a “wet” landfill is, except to tautologically argue that it’s the kind that produces gas. Sometimes, they imply these “wet” landfills are “bioreactor” landfills, yet the universe of those landfills is actually very small.

Alternately, they put a lot of emphasis on “fugitive emissions,” which are those methane emissions that are generated before gas collection is fully operational. Of course gas that is generated before collection begins will not be recovered. That’s a no-brainer. Yet one debunker went to the extreme of insisting that much of the methane gas escaped as fugitive emissions in the first year of being put in a landfill, or it was never made.

But how big an issue are fugitive emissions? Unfortunately, here the science is incomplete. We simply don’t know how many fugitive emissions exist. What we do know is the success that so many landfills have in turning methane emissions into an energy product. That success cannot be denied.

However, it can be overlooked. And the mythbusters go out of their way to ignore the existence of these projects. It’s as if you can prove the earth is flat by simply ignoring all evidence to the contrary.

So this is my challenge to those who deny the reality of landfill gas recovery. Tell me why the 518 operating projects don’t exist or don’t work. Explain how BMW and the University of New Hampshire and SC Johnson really aren’t using landfill gas productively.

Otherwise, go bust a real myth.

Chaz Miller is state programs director for the Environmental Industry Associations, Washington, D.C.

Opinions in this column do not necessarily reflect those of the National Solid Wastes Management Association or the Environmental Industry Associations. E-mail the author at cmiller@envasns.org.

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