Reduction of odours emitting from the facility is a critical aspect of a compost facility due to the immediate negative impact odours have on people living near the site. To provide the necessary odour reduction, air is exhausted from the Receiving Building, the Containers, the Curing area and the Storage area through two biofilters. Each biofilter is designed to treat an airflow of 32,000 CFM. The biofilters were designed using a full plenum under a 1.5m deep layer of shredded root stock media. The biofilter media requires control of both temperature and moisture to maintain efficient absorption of odourous gases. This photo is of biofilter media being manufactured on-site.