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Port Emissions Inventory Guidance

EPA's Port Emissions Inventory Guidance provides methodologies on how to develop port-related and goods movement emissions inventories. This guidance has specific information on how to develop inventories for criteria pollutants and precursors, climate-related pollutants, mobile source air toxics, and energy consumption. This guidance also describes the latest, state-of-the-science methodologies for preparing an emissions inventory in the following mobile source sectors: ocean-going vessels, harbor craft, recreational marine, cargo handling equipment, onroad vehicles, and rail.

The Port Emissions Inventory Guidance is intended to help port authorities and other port operators, state and local governments, Tribes, those doing business at ports (such as terminal operators, tenants, and shipping companies), local communities, and other stakeholders who want to prepare mobile source emission inventories for regulatory, voluntary, and research purposes. Regulatory purposes include inventory developed for inclusion in state implementation plans (SIPs), National Environmental Policy Act (NEPA) analyses, transportation conformity determinations, or general conformity evaluations, among others. The methodologies are broadly applicable to all types of ports, including seaports, Great Lakes ports, and river ports, as well as railyards, freight terminals, intermodal facilities, freight corridors, and other types of facilities that handle and move goods.

For more information and background on the guidance and development process, please visit Ports and Goods Movement Emissions Inventories on the EPA Ports Initiative website.

The full guidance document and downloadable data tables can be accessed below:

Other Materials

Port Emission Inventory Guidance – Public Webinar Slides (October 2020)

This webinar, held on October 29, 2020, covered the methodologies described in the guidance to prepare a port-related emissions inventory for landside and waterside emissions across six port-related sectors: ocean going vessels, harbor craft, recreational marine, cargo handling equipment, onroad vehicles, and rail. The webinar covered the data inputs, methods, and analysis approaches available for developing base year and future year inventories of varying levels of detail and geographic scopes based on user capacity, available resources, and intended end use of the inventory.