MIT Technology Review is reporting that California dairy farmers are adopting innovative manure management systems, such as vermifiltration, to reduce environmental pollution. The publication highlighted the Alberto Dairy in Hickman, California, where third-generation farmer Anthony Agueda uses a biofilter system developed by the Chilean company BioFiltro. This system employs worms and microbes in beds of wood chips and river rock to dramatically cut methane, nitrous oxide and water pollution from cow manure.
The article explained that manure management on dairy and swine farms accounts for a significant portion of U.S. greenhouse gas emissions, with methane and nitrous oxide being potent warming gases. It noted that California, the nation's largest milk producer, has implemented policies, including a 2016 law requiring a 40% reduction in methane emissions by 2030, to address this issue. The state has funneled over a billion dollars into programs promoting cleaner practices.
MIT Technology Review said that while anaerobic digesters, which convert biogas into natural gas and generate carbon credits, have been the primary method for methane reduction, they are expensive and often only viable for large farms. The publication cited concerns that digesters do not fully address water pollution and may divert resources from other solutions. Alternatives like solid separation and vermifiltration are gaining interest, with California supporting 15 vermifiltration projects with over $18 million.
Frank Mitloehner, a professor at the University of California, Davis, studied vermifiltration and found it reduced ammonia emissions from wastewater by about 90%. However, the publication noted discrepancies in methane reduction findings between Mitloehner's independent study and company-funded research, with Mitloehner stressing the need for more independent studies. BioFiltro's vice president of quality and R&D, Patrick Beckett, acknowledged the need for additional independent reviews.
BioFiltro's business model involves owning and operating the systems, with farms covering operational costs. The company generates revenue by selling carbon credits from greenhouse gas reductions to consumer packaged goods makers, such as Nestlé, and plans to sell vermicompost. The publication raised concerns about the integrity of carbon credits, particularly if emissions reductions are not as significant as assumed or if they would have occurred due to impending regulations. Agueda and BioFiltro representatives, however, maintained that carbon credit revenue is crucial for project feasibility. Roberta Franco of the California Department of Food and Agriculture said the state incentivizes vermifiltration for its multiple benefits and economic value.
Full Article: Why worms (and microbes) are catching on as a manure pollution solution