Beta Release of EPA’s Marine Emissions Tools

Today EPA is releasing a beta version of Marine Emissions Tools, a set of R packages designed to calculate emissions from Category 3 commercial marine vessels (CMVs), such as tankers and general cargo ships, in a manner consistent with EPA’s regulations and Port Emissions Inventory Guidance. Emissions from CMVs are a critical input to developing comprehensive emissions inventories for ports. This updated toolset will improve the accuracy of emissions estimates from CMVs and make it easier for stakeholders to develop inventories in a manner consistent with EPA guidance. The beta versions released today may be used to develop inventories to meet regulatory requirements, as well as for voluntary and research purposes. EPA is requesting stakeholder feedback through September 30, 2021.

EPA’s Marine Emissions Tools can be downloaded from or installed directly from GitHub. Questions and other feedback regarding this beta toolset can be posted as issues on the Marine Emissions Tools GitHub page. 

El Paso 2015 Ozone Notification of Availability

On Monday, June 14, 2021, EPA published Intended Air Quality Designations for the 2015 Ozone National Ambient Air Quality Standards; Response to the July 10, 2020, Court Decision Addressing El Paso, Texas and Weld County, Colorado: Notification of Availability and Public Comment Period in the Federal Register, starting a 30-day public comment period on EPA’s intended 2015 ozone NAAQS designations for El Paso County, Texas and Weld County, Colorado. Comments must be received on or before July 14, 2021:

PM NAAQS Reconsideration Announcement

EPA has announced that it will reconsider the previous administration’s decision to retain the particulate matter (PM) National Ambient Air Quality Standards (NAAQS). EPA is reconsidering the December 2020 decision because available scientific evidence and technical information indicate that the current standards may not be adequate to protect public health and welfare, as required by the Clean Air Act.

The press release is available here:

More information on PM NAAQS and other relevant documents can also be accessed on our website here:

Nominations for EPA’s Mobile Sources Technical Review Subcommittee

EPA is seeking nominations from representatives of nonfederal interests such as community and/or environmental justice interests, state and local government interests, environmental advocacy groups, future transportation options and shared mobility interests, transportation, and supply chain shippers, marine and inland port interests, and mobile source emission modeling interests to serve on the Mobile Sources Technical Review Subcommittee (MSTRS; a subcommittee of the Clean Air Act Advisory Committee). MSTRS members are appointed by the EPA Administrator for three-year terms with the possibility of reappointment to a second term. The subcommittee’s website is at The Federal Register Notice announcing the request for nominations was published earlier today, and nominations must be received by August 2, 2021.

Revised Air Quality Designations for the 2015 Ozone NAAQS

In response to a July 2020, D.C. Circuit Court remand, EPA is taking action on its review of the Agency’s original designation for 16 counties for the 2015 National Ambient Air Quality Standards for ozone.  EPA is taking final action to revise the boundaries for six nonattainment areas in four states (Illinois, Indiana, Missouri and Wisconsin) and reaffirming the April 30, 2018, designation associated with Ottawa County, Michigan.  In the case of the Doña Ana County, NM and Denver Metro/North Front Range, CO nonattainment areas, upon further review, EPA intends to revise its initial designation. Because EPA’s intended designations for the associated remanded counties of El Paso, TX and Weld, CO, respectively, disagree with the states’ area recommendations, EPA is sending letters to each state opening a 120-day period for the states to provide additional information based on the existing record. The Agency will notify both New Mexico and Texas of this planned addition.  EPA is also opening a 30-day period for the public to comment. Additional information:;

EPA 120-day letter to Texas:

Technical Support Document: