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[GreenYes] Fwd: Landfill Gas Energy Recovery - National Recycling Coalition Position to USDOE
- Subject: [GreenYes] Fwd: Landfill Gas Energy Recovery - National Recycling Coalition Position to USDOE
- From: Gary Liss <email@example.com>
- Date: Mon, 05 Nov 2001 14:23:17 -0800
Apologies for Cross-Postings
>From: "Peter Anderson" <firstname.lastname@example.org>
>Subject: Landfill Gas Energy Recovery - National Recycling Coalition Position
>Date: Mon, 5 Nov 2001 14:43:27 -0600
> I represent the Landfill Group of the National Recycling Coalition.
> As part of our work, we have done the only extensive investigation of the
> factual underpinnings of the landfill gas energy recovery (LFGER) issue
> from a party that is independent of those with a financial interest in
> maintaining dependence on landfills.
> We have found that the current underpinnings of the policy to
> encourage LFGER in the report cited below, "Forecasting the Growth of
> Green Power Markets in the U.S," as with others from DOE and EPA, are,
> first, inaccurate and, second, fail to look "outside the landfill box"
> where more energy can be recovered compared to LFGER systems and without
> the fatal flaws in current landfill designs.
> For both these reasons, and as is summarized below, the inclusion of
> landfill gas among the sources of green power would be a major setback
> for the green power movement. For one thing, if maximizing energy
> recovery from the latent energy value of discarded materials is the
> criteria, bioconversion of source-separated organic matter will generate
> several times more electricity than the very small fraction of methane
> generation actually captured in gas extraction systems in landfills. For
> another, marketing green power depends upon its sources being free of
> substantive controversy over its environmental benefits. LFGER derives
> from obsolete practices being abandoned in the rest of the developed
> world because of their insoluble environmental impacts.
> We fully understand the DOE's and green marketers' basis for
> supporting LFGER under the assumption that, by productively utilizing the
> Btu value in the gases otherwise flared, combustion -- and methane
> emissions -- in power production elsewhere is displaced.
> However, here are some of the key facts that the landfill industry
> may have failed to share with green marketers about the landfill
> environment that completely turns conventional wisdom upside down:
> (1) There is no factual basis for EPA's assumption that 75% of
> landfill gases are captured at those sites with gas collection systems.
> (2) It would be difficult to make a factual case that much more than
> 10% of total gas emissions from landfills are actually captured.*
> (3) Concerns with landfill gas emissions are not bounded by methane
> emissions, but also, include both carcinogenic volatile organic
> compounds, the bioaccumulative dimethyl form of mercury that is a lethal
> nerve gas produced during decomposition, and presumably other toxic
> compounds from as yet poorly understood interactions in a landfill
> (4) A manager operating a landfill for energy recovery will tend to
> increase the vacuum pressures at the core of the landfill where methane
> generation is densest, and consequently reduce draw from the periphery of
> the site. This operational change tends to increase non-methane emissions
> released in closest proximity to those living or working near the landfill.
> (5) Because landfill barriers, liquid removal and monitoring systems
> "will ultimately fail" in decades (EPA's words), while everyone
> acknowledges the waste load in lined landfills remain hazardous for
> centuries, current designs do not prevent groundwater contamination.
> Rather, they only delay the onset of pollution, and to the very worst
> time -- after all of the responsible parties have left the scene and the
> detection and liquids removal systems have failed.
> (6) The key common component of all these environmental threats is
> the organic fraction of the waste stream (unrecovered paper, food scraps
> and yard trimmings constituting 63% of currently landfilled waste after
> current recovery efforts are accounted for). As organic matter
> decomposes, it creates leachate that draws out the toxic constituents
> from the waste that ultimately find their way into drinking water
> supplies after the barriers fail. Organics also generate the greenhouse
> gas methane that transports VOCs and dimethyl mercury into the
> atmosphere. This is precisely why the European Community has regulated
> the phase-out of land disposal of organic matter, and why co-disposal of
> organics and non-compostable waste in the ground is a discredited and
> obsolete practice that is out-of-place in the 21st century.
> (7) The source of the methane from landfills -- most of which is NOT
> captured -- derives from the anaerobic decomposition of those same
> organic materials that create the myriad environmental problems which
> cannot safely be managed in the ground (described in par. 6). For this
> reason, it is important that those promoting LFGER understand the
> debilitating failings of landfill systems.
> (8) One solution that appears to be extremely promising is to build
> on current diversion policies that have shown themselves to be practical
> and successful. Just like we currently source separate approximately 30%
> of our containers, newspapers and cardboard for recycling, we should give
> the most serious consideration to source separating our organic material
> for either composting or other bioconversion technologies to create
> methane. And, controlled in-vessel decomposition of that single-stream
> organic matter would recover 100% of the waste's energy value without
> toxic complications, not the 10-20% captured from landfills with all of
> the associated concerns for public health.
> While recovery of landfill gas for energy should be accomplished
> where it already exists, recovery should be mandated to protect local
> populations and to meet air pollution and/or climate change related laws
> and policies. Subsidizing the recovery is counter-productive in that it
> creates significant disincentives in the marketplace for the constructive
> -- and truly "green" -- alternative to take hold.
> The purpose of mentioning all this is to suggest that the discussion
> of renewable options on these pages ought to include debate over these
> contrarian facts that undermine one facet of current green marketing
> plans. The opposing facts are so compelling that it is only a matter of
> time before any green marketer associated with landfill gas will find his
> or her entire portfolio needlessly compromised.
> For these reasons, we request an opportunity to present a paper
> laying out these issues, and the citations for them, so that others may
> react and a debate unfurl. We would hope that you would agree that any
> further encouragement of LFGER as part of a portfolio of green energy
> options ought to await the fuller analysis we propose.
> Thank you for your attention.
> Anderson, Chair
> Landfill Group
> Recycling Coalition
>* One of the reasons why landfill gas extraction systems are so
>inefficient is that the vertical collection pipe that pull some of the gas
>from the landfill with a vacuum pump cannot properly be perforated to draw
>gas into the line at the top to ½ of the tube. Otherwise oxygen might also
>be pulled from the surface that would be explosive when mixed with
>methane. Nor can the pipes be drilled to the bottom of the waste load or
>the pipe will penetrate the bottle liner when the waste load decomposes
>and subsides. These factors significantly limit the draw at the top and
>bottom of the landfill.
>In addition, variation in waste densities and barriers to gas flow in a
>landfill from plastic garbage bags and other impediments makes it
>difficult to uniformly draw the gas that aggregates in pools unless the
>pipe happens to have, by chance, been drilled directly adjacent to a gas
>pool. Similarity, pools of leachate that can be found perched high in the
>waste load can flood the pipes, and the gravel pack surrounding pipes can
>become plugged. At greater depths, the densities become so great that
>permeability is reduced to the point that water flows are impeded.
>An even greater set of operating limitations is not reflected in the 50%
>estimates. Often gas collection systems are not installed for 7-10 years
>after waste emplacement begins. By that time, almost half of the first
>wave of gas has been generated and emitted uncontrolled into the
>atmosphere. Moreover, far more than half of the total gas generated by
>today s landfills will occur in a second wave of gas generation decades in
>the future after the end of the mandated post-closure period when the
>landfill cover will fail and rainfall enters the site. By that time, the
>gas collection systems will have been removed from service and all gas
>releases will be uncontrolled.
>Lastly, EPA rules mandating the installation of gas collection systems
>only covered 54% of the waste in the ground in 2000, the rest being at
>sites which were closed before the effective date of the air regulations
>for landfills, or are in landfills smaller than the threshold for coverage
>set by the rules.
>RECYCLEWORLDS CONSULTING Corp
>4513 Vernon Blvd. Suite 15
>Madison, WI 53705
>Fax (608) 233-0011
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