FY2003 OSWER Innovation Pilot Results Fact Sheet
v>EPA
Agricultural and Municipal
Cooperation n Co-composting
Green and Animal Waste
The Environmental Protection Agency's Office of Solid Waste and Emergency
Response initiated a series of innovative pilot projects to test ideas and
strategies for improved environmental and public health results. This series of
fact sheets highlights the innovative approaches, results, and environmental
and economic benefits from the pilot projects that may be replicated across
various sectors, industries, communities, and regions.
PROJECT DESCRIPTION/INNOVATION
EPA awarded an Innovation grant to Sustainable Conservation
to demonstrate and evaluate the technical and economic
feasibility of co-composting green waste—biodegradable
waste such as grass clippings or trimmings from plants, trees
or bushes—and dairy manure in California's Central Valley,
Sustainable Conservation is a non-profit organization that
advances the stewardship of natural resources using innovative,
pragmatic strategies that actively engage businesses and private
landowners in conservation. Through municipal and agricultural
sector collaboration, this waste management approach would
yield environmental and economic benefits including: higher
valued compost, reduction in landfilled material, and minimization
of the environmental impact of dairy operations on water quality.
BACKGROUND
In California's Central Valley, there are approximately 1,600
dairies that produce nearly 20 percent of the nation's milk supply,
These dairies are home to nearly one million milk cows that
create more waste annually than a city of 22 million people,
which is equal to more than 70 billion pounds of waste per
year, Because of the amount of manure produced, protecting
groundwater from nitrate contamination is a major challenge. The
California State Water Resources Control Board estimates that
over 600 square miles of groundwater in the Central Valley are
contaminated with nitrates,
If this waste is not properly applied to crops or stored, it has
significant local and statewide environmental impacts, Dairy
producers and other animal operations face substantia! regulatory
pressures to improve protection of air and water resources. Many
dairy producers export the manure, but offsite options for reuse
of raw manure are increasingly limited, particularly as pathogens
become more of a concern to end users. As an alternative to
exporting, composting dairy manure minimizes groundwater
impacts and is a proven waste management strategy that can
produce a safe product suitable for use as a soil amendment,
•	The addition of manure to green waste (50 percent
by volume) increased the final nitrogen concentration
of the green waste by 13 percent and increased the
overall nutrient value of the co-composted product.
•	Organic matter concentrations increased by over
25 percent and calcium concentrations increased
by a third,
•	No salmonella, fecal or total coliforms were detected in
the final product.
Green waste is also being composted and sold to growers
throughout the Central Valley, Landfill managers are composting
green waste as a method for reducing the volume of waste
disposed in landfills because of state recycling mandates.
Managers are interested iri increasing the market value of the
final compost product since buyers are essential for green waste
recycling programs to succeed, One potential method for creating
higher value green waste compost is to mix green waste with
manure, which is higher in nutrients, In the Central Valley, there
are many dairies in close proximity to urban areas, making it an
ideal location for evaluating the feasibility of creating the co-
composted product,
Cooperation between the urban generators of green waste with
the semi-rural sources of manure could lead to economic and
environmental benefits for both sectors, Municipalities could
enhance the economic value and marketability of their compost,
reduce the amount of material sent to landfills, and provide
a vitally needed service to their agricultural community. The
agricultural sector could find a cost-effective solution for its waste
stream, comply with new nutrient management regulations,
and reduce the environmental impact of its operations on water
quality. This approach could also eventually provide a replicable
manure and green waste management strategy in California and
perhaps in other states as well,

-------
PROJECT SUMMARY
In 2003, the project was initiated using the existing composting
infrastructure at the Merced County Highway 59 Landfill. They
identified dairy producers interested in participating in the project;
determined realistic hauling distance limits; and formalized the
role of dairy membership organizations involved. The cost of
transport, processing and market delivery were assessed and
amounts of new revenue sources determined. These costs and
benefits were compared with other alternatives for dealing with
manure wastes. Participants were surveyed about successes and
lessons learned, and outcomes of the project were disseminated.
RESULTS
The pilot demonstrated that the addition of manure to green
waste compost increases the nutrient value of the final product.
The assessment determined that in order for a project to be cost
effective, sources of dairy manure and compost buyers should
be close to the composting site (within approximately 15 miles).
Operational costs can be further minimized by using existing
equipment and by backhauling the finished compost to growers
who are adjacent to the dairies.
If municipalities can sell, rather than give away their compost
product, the financial viability of the model will be enhanced. For
example, production and net costs indicate that if the co-compost
could be sold for $20 per ton in bulk, the project would break
even. If this price could be achieved and manure delivery costs
were reduced, the co-compost could potentially generate a profit.
2010 UPDATE
As part of the project, the Merced County Highway 59 Landfill
obtained a permit to conduct co-composting onsite. The majority
of the co-composted product created was never sold and instead
was given away for free. By the end of the project, the landfill
facility ceased all co-composting operations due to the increase
in stringent environmental regulations in the State of California.
Other states, including Massachusetts, Maryland, New York,
Wisconsin and Virginia have had success with efforts to co-
compost manure with green waste and other waste products.
Lead: Sustainable Conservation
Sponsor: U.S. EPA Region 9
Other Partners:
•	California dairy producers
•	Merced County, California
OSWER Innovation Projects:
www.epa.gov/oswer/iwg/pilots
Sustainable Conservation:
www.suscon.org/dairies/
EPA Region 9 Dairy Manure Collaborative:
Technologies for Treating Dairy Manure:
www.epa.gov/region09/ag/dairy/tech/composting.html
EPA Sustainable Agriculture:
www. epa. gov/agricu Itu re/sustai n. html
EPA Composting:
www.epa.gov/osw/conserve/rrr/composting/
A PQA United States
Environmental Protection
' m Agency
OSWER Innovation Pilot Results Fact Sheet —
Agricultural and Municipal Cooperation in
Co-composting Green and Animal Waste
May 2011

-------