Quick Answer
Contaminated humanure compost can be safely used as fertilizer after pasteurization or heat treatment to kill pathogens, reducing the risk of disease transmission.
Identifying Contamination
Contaminated humanure compost typically contains pathogens such as E. coli, Salmonella, or other harmful bacteria. Common contaminants include feces from individuals with diarrhea, vomiting, or other waterborne illnesses. These pathogens can also come from external sources like pets, rodents, or wildlife that have entered the compost pile.
Pasteurization Techniques
To kill pathogens in contaminated humanure compost, pasteurization techniques like heat treatment can be used. This involves heating the compost to a minimum of 131°F (55°C) for at least 30 minutes. Another method is solar pasteurization, where the compost is placed in a clear plastic bag and left in direct sunlight for 6 hours on a sunny day. Compost piles can also be turned regularly to ensure adequate oxygen flow and heat buildup.
Best Management Practices
To minimize the risk of contamination, humanure composting systems should be designed with a double-chamber or “batch and batch” system. This allows for adequate decomposition and pasteurization of the humanure in the first chamber before adding it to the finished compost in the second chamber. Regular maintenance and monitoring of the compost pile, including temperature checks and turning, are also essential for producing safe and high-quality compost.
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