ENVIRONMENT

AIR QUALITY

Air quality compliance and improvement activities are key to U. S. Steel's environmental stewardship efforts.

Many of our facilities have Title V operating permits that are required by the Clean Air Act. These permits are enforceable by the issuing agency, usually the state, as well as the US EPA. The Title V permit is unique for each facility, is comprehensive, and is intended to include “all applicable requirements” under the Clean Air Act and underlying regulations that apply to the facility. The permits include emissions limits and standards and work-practice requirements, as well as air pollution control equipment, stack testing, monitoring, record-keeping, and reporting requirements. U. S. Steel is required to provide periodic monitoring reports to the regulatory authorities and certify compliance at least annually, identifying any deviations from the applicable requirements.

Some of our facilities are not required to have a Title V permit. These facilities are typically regulated by installation permits, construction permits, minor source operating permits, permit-by-rules, or a combination of these regulatory and permitting mechanisms. Included in the various permit or rule types are conditions that limit the amount of air emissions; applicable federal, state, and local authority regulations; work practice standards; and monitoring related to the operations and maintenance of air pollution control equipment, reporting of process conditions, and record-keeping requirements.

U. S. Steel is committed to environmental progress and strives for 100% compliance with all federal, state, and local agencies’ rules, regulations, and permit conditions, even as the regulations become more stringent. NOx is produced from a variety of sources, such as car engines, agricultural activities, industrial operations, and even lightning.


Air Emissions 2030 Goal

-10%

We have set a goal to reduce
our corporate NOx emissions
by 10% by 2030, using 2018
baseline levels.


2023 AIR EMISSIONS

 
 

SPOTLIGHT: EMISSIONS CONTROL PROJECTS

Mon Valley Works

Swapping diesel fuel
for battery power

We converted two diesel switcher locomotives at our Mon Valley Works’ Edgar Thomson and Clairton Plants to battery power. The conversion represented a more than $2.3 million investment, with the remaining cost offset through a partnership with the Pennsylvania Department of Environmental Protection (DEP). It will be worth it: the change is expected to reduce airborne particulate matter (PM2.5) emissions by 770 pounds annually — equivalent to the amount emitted by 7,000 gasoline-powered passenger vehicles. The move will also reduce the amount of diesel fuel consumed at the facilities by 40,000 gallons annually.

Gary Works

Reducing natural gas usage

The Gary Works facility undertook several projects to reduce purchased natural gas used as boiler fuel by increasing the utilization of the blast furnace gas by-product back into the system. One of these projects, tracked and monitored by our metriX platform, improved the reliability of the gas main that supplies blast furnace gas to all the boilers. The usage of blast furnace gas was maximized and resulted in reduced natural gas purchase and saved $7.6M in 2023. Over the span of four years, 699,807 MMBtu of natural gas has been offset.

ENVIRONMENTAL AREAS OF FOCUS

U. S. Steel’s current environmental areas of focus align with the results of our ESG Materiality Assessment.