Friends of Rural New York

 
 The use of methane digesters to produce energy from animal manure 
 may have a role in addressing environmental problems and meeting energy needs, 
 but the Sierra Club opposes public subsidies to such energy generation at 
 large concentrated animal feeding operations (CAFOs) because of the 
 environmental and social damage associated with them: polluting our waters and our 
 air;  excessive use of antibiotics and hormones; mistreatment of animals; and harming
 rural communities and small farms.

 
 SIERRA CLUB GUIDANCE: METHANE DIGESTERS AND CONCENTRATED ANIMAL 
FEEDING  OPERATION (CAFO) WASTE
 
METHANE DIGESTERS: WHAT ARE THEY?
 
 Methane digesters are anaerobic (low or no oxygen) chambers which 
 facilitate the breakdown of manure by anaerobic bacteria with the release of 
 methane and other gases as a byproduct of their metabolism, ammonia, nitrogen, 
 hydrogen sulfide, and sulfur dioxide.  Methane can be burned directly in stoves or 
 burners, to heat the digester, and it can be converted to electricity.  There 
 are several different types of systems but all commercially available systems 
 are expensive to install and require manure from a large number of animals to 
 operate.
 (Fulhage et al. 1993)
 
IS THERE A ROLE FOR METHANE DIGESTERS ON SMALL FARMS?
 
 The purpose of this policy is to address the use of methane 
 digesters to handle animal waste generated by concentrated animal feeding
operations 
 (CAFOs), as that term is used in the Clean Water Act.  However, it is also 
 necessary to consider the use of methane digesters on farms with livestock that 
 are not CAFOs.  This may include farms with large numbers of animal units 
 but with enough pasture (the animals go to the feed)  so that it is not an 
 "animal feeding operation” (AFO - the feed is brought to the animal).  It 
 may also include farm operation where the animals are confined but where the 
 number of animal units is below the regulatory definition of a CAFO.  The 
 Sierra Club believes that large farms with sufficient pasture are unlikely 
 candidates for methane digesters.  Therefore, this policy will use the term “small 
 farms” to describe farms that are not CAFOs.
 There is some evidence that methane digesters can offer significant manure
management benefits for small farm operations
(U.S. EPA Office of  Air and Radiation, Spring 2002).  
Digesters can substantially reduce odor  and releases of methane,
a powerful global-warming gas; can convert nitrogen into 
 ammonium, a form more available to plants and less likely to be carried away 
 with runoff  when the remaining waste solids are land-applied; can reduce fly 
 infestation; and can reduce the oxygen-depletion capacity of the remainin
waste although the liquid waste does still require additional treatment prior to 
 release. On the other hand, the land application of manure is the most 
 environmentally  responsible method of manure management where there is
sufficient  land to insure that manure application will not exceed soil absorption 
 capacity and crop and pasture nutrient needs and where the land application practices 
 do not cause a nuisance.  Therefore, the Sierra Club will consider the role of 
 methane digesters on small farms as requiring a case-by-case evaluation.  
 The use of  public money to subsidize methane digesters on small farms requires 
 public participation, community support, transparency and accountability.
 
DO DIGESTERS MITIGATE THE ENVIRONMENTAL IMPACTS OF CAFOS?
 
CAFO waste streams are so large and contaminated that methane 
 digesters mitigate only a small fraction of their environmental damage. 
Equipment costs (U.S. EPA Office of Air and Radiation, Winter 2002) and maintenance for 
 conversion to energy are high. The biogas must have ammonia, moisture, and 
 particulate pollution (dust) removed, and then be compressed.  It requires 
 additional cleaning if it is to be sent into a natural gas pipeline. Most environmental
damage caused by CAFOs, however, remains unabated. Excess nutrients which run
off from waste lagoons or land-applied waste residuals suffocate the life out of our waters.
The volume of solid waste  remaining is not significantly diminished and requires
proper disposal (Iowa State University et al. 2002). The solid waste is often land applied
as “fertilizer” or “soil conditioner” but can pose problems because anaerobic
digestion does  not remove antibiotics and heavy metals passed by dosed swine and poultry.  
In  addition, although pathogen numbers decrease, the decrease may be ephemeral as 
 the pathogens regrow (Gibbs et al. 1997).  Numerous studies have demonstrated that these
toxic and pathogenic contaminants are entering the environment 
in substantial concentrations (Giger et al. 2003, Huang et al. 2001, 
 Kolpin et al. 2002, Union of Concerned Scientists et al. 2002). Further, digesters 
 pose a risk of explosion and create both nitrogenous and sulfurous gases which 
 may be emitted.  In sum, the potential for methane digesters to partially 
 mitigate  some of the extensive and pervasive damage caused by CAFOs does not 
 justify the use of this technology as a basis to support the development of new 
 CAFOs.
 
 Existing CAFOs may reduce the problems they are currently causing by 
 use of methane digesters.  However, they should be installed at the cost of 
 the CAFO owner and not from public subsidy.
 
HOW CAN THIS TECHNOLOGY BE UTILIZED ON SMALLER FARMS?
 

 While focusing primarily on serving CAFOs, the joint US EPA - USDS - 
 DOE AgStar program and a number of commercial providers have assisted in the 
 Development and installation of digesters on smaller farms.  Where methane 
 digesters are  able to operate on small, non-CAFO operations where antibiotic use 
 is limited to  treatment of disease rather than to promote faster weight gain, 
 where animals are free of growth hormones, and where toxic and pathogenic 
 byproducts of the digesters are controlled, there is a potential for methane digesters 
 to provide beneficial waste treatment. In such situations we should seriously 
 consider supporting smaller farms which are working towards adopting these 
 potentially sustainable practices by ensuring that they have fair access to 
 methane digester technology.
 
 
 HOW ARE METHANE DIGESTERS REGULATED?
 
 The federal AgStar program is aimed at reducing greenhouse gases and 
 Providing energy while protecting the environment.  AgStar has developed 
 interim standards, presently voluntary, for the construction and operation 
 of several types of manure digesters. (USDA-NRCS Biogas Interim Standards).  
 Though these federal standards require compliance with local and state 
 regulations,  the adequacy and  thoroughness of local and state regulations varies 
 substantially across the nation and some states do not address digester operations 
 at all  (Iowa State University et al. 2002).  This is not enough 
 environmental protection.  The Sierra Club wants the standards to become mandatory,
 inspections to be routine, and enforcement to be effective. We want 
 testing and limits protective of natural resources, human health, and human 
 quality of life to be set for metals, antibiotics, hormones, pathogens, 
 odor-producing and airborne compounds, and other pollutants released from digester 
 effluent,  residual sludge, solid waste fertilizer, and other byproducts of both CAFOs 
 and methane digesters.
 
 SHOULD CAFO-DERIVED METHANE GAS BE INCLUDED IN A
RENEWABLE ENERGY PORTFOLIO?
 
NO.  A fuel that damages the environment is not “renewable”.  The 
 Anaerobic decomposition of CAFO manure, like the decomposition of garbage in 
 landfills, and waste-burning incinerators, is symptomatic of inefficient waste 
 treatment, treatment necessitated by inefficient, wasteful industries, 
 practices, and processes.  The Sierra Club favors conservation of materials and 
 energy, energy efficiency in processes and operations, and the recycling of 
 materials over the thermal destruction of materials for their energy content. Small 
 farms which utilize land sufficient to support the number of animals being raised can
be operated so that the land, air, and water are not degraded and the 
 waste can be recycled into the soil rather than accumulating and decomposing via 
 the  methane-generating anaerobic process.  CAFO waste lagoons and 
 landfills release heat, a waste of thermal energy and methane, a waste of chemical 
 energy. Capturing energy from these processes reduces some of the 
 environmental damage associated with these wasteful and inefficient systems but it 
 doesn’t move us towards a clean, renewable energy future which must be built upon 
 conservation, efficiency, and material recycling.
 
SHOULD DIGESTERS BE SUBSIDIZED?
 
 Subsidies for energy production from digesters have become a 
 frequent provision in energy legislation. Some fossil fuel use may be displaced by 
 methane digesters but it is a small amount. Similarly, some global warming 
 gas emissions are reduced by the use of digesters but CAFOs are a minor  
 contributor overall (U.S. EPA, April 2004).  The benefits of methane digesters 
 in terms of energy policy are small so subsidies for CAFO digesters are not 
 consistent with  good energy  policy. The fuel for digesters is  primarily CAFO 
 manure, a waste which depletes and degrades natural  resources. In evaluating 
 whether a subsidy under consideration might be supportable, one must consider whether 
 the subsidy would produce greater environmental gains if applied, for instance, 
 to a clean,renewable energy source.
 
For forward-thinking energy policy, we have to take a broader 
 perspective.   A public subsidy of  $200,000 in public money could provide about 50% 
 of the funding necessary for a digester which could collect the methane 
 generated by the water-flushed manure of 1,000 dairy  cows, methane which would 
 be burned for energy and would emit pollutants into the atmosphere.  That same 
 funding could pay for the installation of wind turbines which would supplant 
 fossil fuel burning on that same farm without emitting air pollutants.  That 
 same funding could subsidize smaller dairy farms which generate dry manure rather 
 than water-flushed manure; dry manure generates only minimal amounts of 
 methane.  As citizens, it is our responsibility to “do the math” and to ensure 
 that we are looking towards long-term solutions, not just short-term fixes.
 
 DO WE SUPPORT LEGISLATION PROMOTING DIGESTERS?
 
Many states are now considering legislation which promotes renewable 
 energy and includes methane digesters as a potential source for such energy. 
 The Sierra Club prefers clean, renewable energy sources over CAFO waste so 
 Legislation should be evaluated to ensure that support for clean renewable fuels 
 is strong.We also want to ensure that when methane digester energy is included 
 in legislation, it’s impacts are adequately regulated and small farms 
 are provided with fair access to the technology and to the energy grids which 
 permit the sale of the energy. Smaller farms may require additional access and 
provisions to allow them effective and fair access. Promoting the development and
deployment of clean renewable energy technology is a high priority for the Sierra Club. 
Club entities are encouraged  to advocate as much as possible for clean sources of
renewable energy, and to oppose inclusion in RPS legislation and other relevant proposals
of alleged sources  of renewable energy that encourage or subsidize environmentally
questionable practices, such as CAFOs or waste combustion.
 
 SHOULD WE SUPPORT OR OPPOSE NEW DIGESTERS IN OUR OWN COMMUNITIES?
 
The Sierra Club opposes the development of new CAFOs, and, therefore 
 opposes new CAFOs with methane digesters because the problems of CAFOS will 
 greatly outweigh the potential benefits of methane digesters.  However, 
 communities with existing CAFOs face a different situation.   In these communities, 
 the decision will be a local, case-by-case decision.  Local, state, and federal 
 environmental laws should be in place to protect public health and the environment 
 from the impacts of CAFOs.   Existing CAFO owners must comply with all these 
 laws and must have invested in the technologies needed to eliminate all forms 
 of pollution.
 
Sierra Club groups and communities should work together to analyze 
 and decide on a case-by-case basis whether the good results of installing a 
 methane digester at a local facility outweigh the bad. Methane digesters can provide 
 substantial relief from the odor and flies which plague nearby homes and 
 communities (Painet al. 1990, Wilkie 2000) as well as providing some reduction in 
 greenhouse gases and supplanting of fossil fuel use (Martin 2003, US EPA Office 
 of Air and Radiation 2003). Their emissions, however, must be controlled and  
 safe operation ensured.  The Club can assist communities by assuring that the public
participation process is robust, that all relevant information is  made available
to the public, and that federal, state, and local environmental regulations will
fully protect the environment and permit requirements will be met 
 and enforced.
 
 References and Citations
 Fulhage, Charles, Sievers D, Fischer JR (1993) Generating Methane 
 Gas from Manure. University of Missouri Extension Publication G1881.
 < <http://www.usask.ca/agriculture/caedac/dbases/MANURE1.html
 http://www.usask.ca/agriculture/caedac/dbases/MANURE1.html
 
Gibbs RA, Hu CJ, Ho GE, Unkiovich I (1997)  Regrowth of faecal 
 coliforms and salmonellae in stored biosolids and soil amended with biosolids. 
 Water SciTechnol 35(11-12):269-275.
 
 Giger W,  Alder AC, Golet EM, Kohler HE, McArdell CS, Molnar E, 
 Siegrist H Suter MJF. (2003) Occurrence and fate of antibiotics as trace
contaminants in wastewaters, sewage sludges, and surface waters.  Chimia 57(9):  485-491.
 
Huang CH, Renew JE, Smeby K L, Pinkston K and Sedlak DL 
 (2001).Assessment of Potential Antibiotic Contaminants in Water and Preliminary 
 Occurrence Analysis.Water Resources Update120:30-40
 
 Iowa State University and the University of Iowa Study Group (2002) 
 Iowa Concentrated Animal Feeding Operations Air Quality Study.
 <http://www.public-health.uiowa.edu/ehsrc/CAFOstudy.htm
 http://www.public-health.uiowa.edu/ehsrc/CAFOstudy.htm
 
Kolpin, D.W.; Edward T. Furlong; Michael T. Meyer; E. Michael 
 Thurman;Steven D.Zaugg;  Larry B. Barber ;Herbert T. Buxton (2002)
Pharmaceuticals, 
 Hormones, and
 
 Other Organic Wastewater Contaminants in U.S. Streams, 1999-2000: A 
 National Reconnaissance, Environmental Science & Technology, 36(6):1202-1211
 :http://pubs.acs.org/cgi-bin/jtextd?esthag/36/6/html/ es011055j.html
<http://pubs.acs.org/cgi-bin/jtextd?esthag/36/6/html/es011055j.html
 http://pubs.acs.org/cgi-bin/jtextd?esthag/36/6/html/es011055j.html
 
 Martin, John H. 2003.  A Comparison of Dairy Cattle Manure 
 Management with and without Anaerobic Digestion and Biogas Utilization.
Submitted to: US  EPA AgStar
 Program by Eastern Research Group Inc.
 :http://www.epa.gov/agstar/pdf/nydairy2003.pdf
<http://www.epa.gov/agstar/pdf/nydairy2003.pdf
 http://www.epa.gov/agstar/pdf/nydairy2003.pdf
 
Pain, B.F.; T.H. Misselbrook, and C.R. Clarkson.  (1990). Odour and 
 Ammonia emissions following the spreading of anaerobically digested pig 
 slurry on grassland.  Biol. Wastes 34: 259-267.
 
Union of Concerned Scientists.  August 2, 2000 Letter to US EPA 
 Assistant Administrator Charles Fox “Limit Vital Antibiotics in Factory Farm 
 Effluent”
 
 Signed by Sierra Club and other organizations.
 
 U. S, EPA - April 2004.  INVENTORY OF U.S. GREENHOUSE GAS EMISSIONS 
 AND SINKS:1990-2002.
<http://yosemite.epa.gov/oar/globalwarming.nsf/UniqueKeyLookup/
 LHOD5MJTM5/$File/
 http://yosemite.epa.gov/oar/globalwarming.nsf/UniqueKeyLookup/
 LHOD5MJTM5/$File/
 2003-final-inventory_ES.pdf
<http://yosemite.epa.gov/oar/globalwarming.nsf/UniqueKeyLookup/
 LHOD5MJTM5/$File/2
 http://yosemite.epa.gov/oar/globalwarming.nsf/UniqueKeyLookup/
 LHOD5MJTM5/$File/2 003-final-inventory_ES.pdf
 
 Wisconsin Department of Natural Resources,  “Frequently Asked 
 Questions -Concentrated Animal Feeding Operations”
http://dnr.wi.gov/org/water/wm/nps/ag/faq_cafo.htm
http://dnr.wi.gov/org/water/wm/nps/ag/faq_cafo.htm#q1
 http://dnr.wi.gov/org/water/wm/nps/ag/faq_cafo.htm#q1