[USCC] Landfill

[Tamara Thomas]

Myron,
	I heard Dr. Sally Brown of the University of Washington speak to the landfill gas collection issue a year or so ago.  As I recall, the problem with claiming that landfill gas collection is a carbon neutral or positive technology has to do with the fact that the greatest percentage of methane is generated within the first year or two.  Generally a landfill is not covered immediately, and it takes some time to fill, cover, and implement the landfill gas system.  During that initial time, according to Dr. Brown, most of the methane has been generated and lost.  An abstract of "Is Converting Landfill Gas to Energy the Best Option?" by Janet Pelley, in Environ. Sci. Technol., quotes her as saying "...[methane] capture rates over a landfill’s lifetime can be as low as 40−50%...".

	I recommend contacting her and/or researching her publications on the issue.

Best wishes,

Tamara Thomas, P.E.
Terre-SourceLLC
Helping Compost Happen!
360-336-3536 Office
360-336-3530 FAX
425-844-6068 Field

-----Original Message-----
From: hirschsys at aol.com [mailto:hirschsys at aol.com] 
Sent: Tuesday, December 30, 2008 2:22 PM
To: compost at mailman.cloudnet.com
Subject: [USCC] Landfill


For future discusions:

As active landfills put in gas collection systems they sometimes claim to now be a recycling option because they capture?some of the methane.? This has actually caused the closing of some good composting operations due to yard trimmings being diverted back into landfills.

Does someone have the?statistics on this subject?? Estimates of the carbon going into a landfill would be fairly?easy to calculate, the captured methane coming out is measureable.? An estimate of how long a landfill will continue to produce is? available so therefore an efficiency should?have been calculated.? I am sure it has , I just don't remember it.

Could someone from the compost?group help me on this.???

Thank you
Myron Hirschman?