In California, policies to separate and divert organic waste from landfills may also be diverting the associated CH4 emissions to alternative locations. and reported large CH4 plumes from dry digestion and open-air composting facilities, attributing the plumes to an exhaust system, organic waste bags, and curing compost. The studies noted that composting facilities are currently excluded from state or federal emissions self-reporting and that these sources are missing from BU inventories . Whether organic waste diversion is reducing or shifting CH4 emissions is an outstanding research question.