U. S. Steel Pioneers Battery-Powered Locomotives, Reinforces Commitment to Sustainability and Community

United States Steel Corporation ("U. S. Steel" or the "Company") (NYSE: X) announced today a significant step in its ongoing commitment to sustainability, environmental excellence and the communities it serves. The company converted two of its diesel switcher locomotives at the Mon Valley Works' Edgar Thomson and Clairton Plants to state-of-the-art battery-operated locomotives. The locomotives are built by Innovative Rail Technologies (IRT), a provider of customized lithium-ion propulsion solutions to the locomotive rail market. U. S. Steel invested more than $2.3 million in the locomotives while the remaining cost was offset through a partnership with the Pennsylvania Department of Environmental Protection (DEP).

The locomotives, which travel within the facilities carrying steel, coke, scrap metal, iron ore, and other materials necessary for production, are expected to reduce airborne particulate matter (PM2.5) emissions by .385 tons - the equivalent emissions of 7,000 gasoline-powered passenger vehicles.

"Mon Valley Works is the first industrial site to deploy this technology to reduce small particulate matter emissions from its locomotive fleet," said Scott Buckiso, Senior Vice President and Chief Manufacturing Officer, U. S. Steel. "Advancing our Best for All^® strategy means producing solutions that benefit our customers and communities, people and planet. This includes investing in technological advancements at our facilities."

The switch to battery-powered locomotives will reduce the amount of diesel fuel consumed at the facilities by 40,000 gallons annually, reduce airborne particulate matter, and demonstrate the company's use of emerging technology to help reach the goal of achieving net-zero emissions by 2050.

"We are proud to bring this innovative and sustainable technology to U. S. Steel's Mon Valley Works," said Ira Dorfman, Principal, IRT. "Battery propulsion technology is already in use throughout many modes of transportation, and rail transportation is the next step."

U. S. Steel partnered with the Pennsylvania Department of Environmental Protection to utilize the agency's Driving PA Forward - Marine and Rail Freight Movers Grant Program to offset the cost of the new battery-operated locomotives. The Driving PA Forward initiative improves air quality in Pennsylvania through the transformation from older diesel engines to cleaner technologies to help the state meet its diesel emissions reduction goals.

U. S. Steel unveiled the locomotives to the employees, members of the community, media, and elected officials at an event on October 30, 2023, at the Mon Valley Works ? Clairton Plant.

About U. S. Steel

Founded in 1901, United States Steel Corporation is a leading steel producer. With an unwavering focus on safety, the Company's customer-centric Best for All^® strategy is advancing a more secure, sustainable future for U. S. Steel and its stakeholders. With a renewed emphasis on innovation, U. S. Steel serves the automotive, construction, appliance, energy, containers, and packaging industries with high value-added steel products such as U. S. Steel's proprietary XG3^® advanced high-strength steel. The Company also maintains competitively advantaged iron ore production and has an annual raw steelmaking capability of 22.4 million net tons. U. S. Steel is headquartered in Pittsburgh, Pennsylvania, with world-class operations across the United States and in Central Europe. For more information, please visit www.ussteel.com.

About Innovative Rail Technologies

Innovative Rail Technologies (IRT) is a rail solutions provider offering its proprietary technology ATLAS (Advanced Technology Li-Ion Adaptive System). ATLAS is a turnkey, scalable propulsion and control package customized to the unique needs of customer operations. Paired with automated, high-speed charging, IRT's ATLAS-powered locomotives maintain 24/7 availability for its operators in an economically beneficial package. IRT was established in 2019 and has a rapidly expanding list of customers which includes Fortune 500 companies, Ports, Industries, and Short Line Railroads. IRT works with its growing nationwide network of locomotive remanufacturers (ATLAS Authorized Installers) and can also provide ATLAS kits directly to customers for in-house remanufacture. More information about the company can be found at: www.InnovativeRailTech.com.