EMISSION FACTORS FOR GRAIN RECEIVING AND FEED LOADING OPERATIONS AT FEED MILLS

The Federal Clean Air Act (FCAA) Amendments of 1990 have impacted the process used by State Air Pollution Regulatory Agencies (SAPRAs) in re gulating air pollution attributed to agricultural facilities, includin g feed mills. The maximum allowable emission rate (AER), annual emissi on rate and Title V emission fee for a pollution source are calculated using AP-42 emission factors published by the Environmental Protectio n Agency (EPA). For proper enforcement, there is a need to be as accur ate as possible in establishing emission factors for any emitting sour ce. The 1988 AP-42 emission factors for feed mills totaled 4905 grams of particulate/tonne (9.8 lb/ton) of grain handled. These factors were grossly in error: EPA published interim factors in 1996 based on data obtained from air sampling performed at grain elevators. There are di fferences in the operations of grain elevators and feed mills associat ed with feed yards that could significantly affect emission factors. A dditionally, no data was available to EPA on the emission rate and emi ssion factor associated with loading feed. This study was directed at developing accurate emission factors for unloading grain and loading f eed at feed mills associated with cattle feed yards. The resulting emi ssion factors were determined to be 20 grams/tonne (0.04 lb/ton) for u nloading grain and 2.5 gram/tonne (0.005 lb/ton) for loading feed.