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[GreenYes] Fwd: Landfill Gas Energy Recovery - National Recycling Coalition Position to USDOE
Apologies for Cross-Postings

>From: "Peter Anderson" <anderson@recycleworlds.org>
>To: <jim_leyshon@nrel.gov>
>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 
> environment.
>
>     (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.
>
>                                                            Peter 
> Anderson, Chair
>                                                             Landfill Group
>                                                              National 
> 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  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.
>
>
>______________________________
>Peter Anderson
>RECYCLEWORLDS CONSULTING Corp
>4513 Vernon Blvd. Suite 15
>Madison, WI 53705
>(608) 231-1100
>Fax (608) 233-0011
><mailto:anderson@recycleworlds.org>anderson@recycleworlds.org

Gary Liss
916-652-7850
Fax: 916-652-0485

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