September 20, 2004 | General


BioCycle September 2004, Vol. 45, No. 9, p. 64
An organization called Sustainable Conservation facilitates cooperation between municipalities and farms on organics reuse projects.
Allen Dusault

FOUNDED in 1992, a San Francisco-based organization, Sustainable Conservation, has combined business strategies with environmental priorities to advance specific projects. Our Dairy Program has had tremendous success in the last couple of years in promoting better manure management – focusing on management practices, regulations and policy, and new initiatives.
With a $43,000 grant from EPA, Sustainable Conservation began an innovative manure reuse project. Dairy manure was first delivered to the Merced County Highway 59 landfill facility and mixed with urban green waste beginning summer 2004. The key partner in the project is Jerry Lawrie, Merced County’s Integrated Waste Program Manager. He was also involved in the unexpected nine month permit process to get a composting “research” permit through the California Integrated Waste Management Board. Because of differing regulatory interpretations about what was required, CIWMB’s regulatory division took an exceptionally long time to review the application and grant approval – delaying the project start date.
The goal of the project is to provide dairymen with another option for managing manure. Based on new regulatory requirements from the Region 5 Water Quality Control Board, a new CAFO rule from EPA and new standards from NRCS on suitable land application rates, particularly of nitrogen, most dairies in California’s Central Valley will need to either reduce the number of cows they have on their farms, increase their acreage in crop production or send more of their manure off-site. The only real option for most dairies will be to export nutrients. But that may be expensive and could overwhelm existing commercial manure compost operations.
Composting manure at an existing municipal composting facility that has already invested in labor, equipment, land and permitting would seem like a cost-effective solution. That is what this project hopes to demonstrate.
We are measuring the nutrient content and solubility in the feedstock and comparing data collected with the final composted product. Our hypothesis is that composting will decrease nitrogen mobility, thereby reducing the potential for nitrate leaching to groundwater when the compost is land applied as a soil amendment and fertilizer.
A & L Western Agricultural Laboratories, which is the same company regularly used by the Highway 59 composting facility, was selected to complete the analysis. By using the same laboratory, characteristics of the compost produced with this project can be compared to historical data on Highway 59 compost quality.
Ken Stone & Family – a local manure hauling and spreading company – was contracted to deliver 500 cu yds of manure to the Highway 59 facility at $90 per load. The manure hauling trucks typically haul between 35-50 cu yds per load, depending on moisture content of the manure. To facilitate the composting process, Jerry Lawrie suggested that we obtain manure with high moisture content; hence each truck was able to deliver 35 cu yds per load. Total manure delivery costs were $1,260. The result after mixing manure with urban green waste for composting should be about 500 cu yds or 250 tons of finished compost. High quality compost in bulk sells for about $10/cu yd generating $5,000 in income, and is also advertised at $15/cu yd on the Highway 59 website. Sold at the latter price, 500 cu yds would sell for $7,500.
The cost to Merced County for the composting process is approximately $4-$8/cu yd, or $2,000 – $4,000 to produce 500 cu yd. At the $4/cu yd production cost and $10/cu yd sales price, the project would generate a profit of approximately $1,700. If compost is sold for $15/cu yd, the profit margin would be between $4,200 and $2,760 (for the $4/cu yd and $8/cu yd production costs, respectively).
Partnership with a manure hauling and spreading company is critical to facilitating the cocomposting of manure and urban green waste at the Highway 59 site for the long-term. Located about 5 miles from the Highway 59 composting site, Ken Stone & Family have established a profitable business collecting manure, composting it and spreading it on agricultural land. Steve Stone explained that he gets dairy manure for free (or for a negligible cost) within a 20-mile radius of his operation (beyond that dairymen have to pay). It costs him $10/ton to produce and he sells finished compost for $20/ton, primarily for cotton, tomato, orchard trees (such as almonds) and alfalfa crops. Profitability of his operation is dependent on free or very low cost for the dairy manure.
Composting of manure with urban green waste in California has recently been placed under far greater regulatory burden and scrutiny, to the extent that current regulations are a significant barrier to broader implementation of manure and/or manure/green waste composting. Recognizing that green waste composting poses a far lower water quality risk than other high priority discharges, from 1996 to 2000, many Regional Water Quality Control Boards issued waivers of Waste Discharge Requirements for green waste composting facilities. Passed in 1999, SB 390 inadvertently rescinded these waivers. Additionally, in this interim, the California Integrated Waste Management Board issued new permitting requirements that removed animal manure from the green waste category. The result is that green waste and animal manure composting facilities have to obtain permits through Title 27 (designed for solid waste landfills) — a regulatory process that is time consuming, technical and expensive. Given the low profit margins involved in the composting of green waste and manure, these new regulatory requirements effectively negate the start-up of new composting facilities, and could possibly force small operations (such as Ken Stone & Family) out of business.
Additionally, while dairymen can use as much compost as they want on their farms, they cannot give away or sell more than 1,000 cu yds compost per year without applying for a composting facility permit. In contrast, there are no regulatory limits indicating how much manure can be sold and transported off the farm. Given that many dairies will need to export nutrients in order to meet new water and air regulatory requirements, transporting manure as compost, which is lighter and poses a lower economic risk than manure, is an environmentally beneficial practice that is eliminated as a reasonable option by these regulations.
In general, we are advocating that the CIWMB and State Water Resource Control Board revise their regulatory policies, or reissue waivers, so that cocomposting agricultural manure with urban green waste and/or making compost on farm and then moving it elsewhere, are options for both dairymen and composting facilities. We are working diligently to educate both the dairy community and regulatory/government agencies about this problem. In conclusion, this project will be completed as scheduled but was significantly delayed by regulatory barriers. Removing these regulatory barriers will be a major part of the effort to promote dairy manure and green waste composting in California.
Allen Dusault is Senior Project Manager at Sustainable Conservation in San Francisco. He can be contacted via e-mail at
AS PART of its Dairy Program, Sustainable Conservation has been participating in a $10 million grant program to build methane digesters on California dairies. Twelve new digesters are in construction or are operational. We have also won passage of net metering legislation for digesters and successfully challenged the utilities before the Public Utility Commission (PUC) winning two favorable decisions for net metering (making digesters more financially viable). Goals of the project include:
o Demonstrating the viability and cost effectiveness of digester technology;
o Evaluating potential air quality benefits, particularly VOC and ammonia;
o Developing expertise and workable digester model in anticipation of funding for future efforts; and
o Providing assessment of technical and regulatory barriers to implementation.
The utilities have not been helpful in hooking-up digesters to the electricity grid, and in fact have made it very difficult. Twice, Sustainable Conservation has had to argue before the PUC to get the net metering tariffs applied as the legislation intended. We won both times. We also have to translate that into getting digesters hooked up and will be working on new legislation later this year that will help our progress.
Sustainable Conservation has been evaluating the production of biofuels from agriculture as a renewable source of fuel for California’s vehicles. We recently returned from Sweden where we toured biomethane production facilities as part of a $300,000 study for USDA on the viability of producing biomethane in California. We are also moving ahead on a biodiesel initiative to promote it as an alternative fuel in California.
At the BioCycle West Coast Conference in San Francisco, California, March 7-9, 2005, Allen Dusault will speak about the anaerobic digestion, renewable fuels and composting projects moving forward in the state.

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