A Connecticut engineering firm retained by U.S. Steel to investigate the deadly Aug. 11 explosion at its Clairton Coke Works facility today released preliminary findings. The firm, Engineering Design & Testing Corp., issued the following information on its website Thursday: The explosion took place in the 13-14 Coke Battery transfer area when an 18-inch cast iron valve ruptured, releasing flammable coke oven gas, which subsequently exploded. The valve was originally manufactured in 1953 and underwent refurbishment approximately ten years ago. Damage to other valves at 13-14 Coke Battery was determined to have resulted from the explosion. At the time that the valve ruptured, U. S. Steel employees and employees of MPW Industrial Services were opening and closing the valve to ensure proper operation in advance of planned maintenance activities. As part of the valve opening and closing work, water at a high pressure was introduced into the valve in order to flush accumulated deposits. A sealed cavity inside the body of the valve filled with high-pressure flush water in excess of the pressure rating of the valve. This resulted in a sudden and complete rupture of the valve body, releasing combustible coke oven gas. The coke oven gas accumulated in the transfer area basement and exploded when it reached an ignition source at the adjacent 14 Battery. Among the findings? The firm determined that U. S. Steel did not have a specific procedure addressing the use of high-pressure water to flush valves.  “U. S. Steel does have an established Management of Change procedure that should have been used to evaluate the change from low pressure steam to high pressure water,” the report stated. U.S. Steel Thursday morning announced the findings on its social media platforms and issued a statement that read in part: “These initial findings are consistent with our own, and we remain committed to working closely with all parties involved in investigations—including the Chemical Safety Board, OSHA, and EDT—to ensure a comprehensive understanding of the event. In parallel, we continue our investigation, and we’ve already strengthened several safety protocols based on what we’ve learned.” Editor’s Note: Stay tuned. GASP continues to follow this issue closely and will keep you posted. Please check out our Clairton Explosion resource page  for the latest developments, documents obtained through public records requests, and a timeline of events.

Calling all Westmoreland County residents: The time to weigh in on the long-awaited Title V operating permit for the Tenaska Westmoreland Generating Station is NOW.   But how we got here and what’s in that permit will take a little bit of explaining…   How We Got Here   A couple of years ago, we blogged  about testing issues at the Tenaska Westmoreland Generating Station in South Huntingdon Township, Westmoreland County. For the uninitiated: Tenaska is a 940-watt, natural gas-fired power plant with two large turbines.    The Pennsylvania Department of Environmental Protection (DEP) issued a Plan Approval to authorize the plant’s construction in April 2015, and the plant began operating under the terms of that Plan Approval in December 2018.     In the regular course, once a major source of air pollution like Tenaska begins normal operations, it conducts a round of performance tests to establish proper operating limits and then must apply to DEP for a Title V Operating Permit that will incorporate those limits.    However, in January 2019, during one of the final performance tests at Tenaska, a malfunction with the testing equipment caused an invalid reading that prevented the plant’s operator from applying for a Title V Operating Permit.    Investigating the cause of the malfunction took some time (months) and then the plant’s operator and DEP could not agree on a new testing protocol. In the meantime, Tenaska continued to operate under its Plan Approval.   About Tenaska’s Title V Operating Permit   We’re pleased to report that Tenaska and DEP seem to have resolved those issues: This past  July, Tenaska submitted its application for a Title V Operating Permit, and in the Oct. 5 edition of the Pennsylvania Bulletin, DEP announced that it has prepared a draft Title V Operating Permit for the plant.    That draft Title V Operating Permit, DEP’s Review Memo, and Tenaska’s Permit Application are available here , here , and here .   What Pollution Tenaska Will Be Permitted to Emit   Here’s the interesting part: In the years Tenaska has operated the facility under its Plan Approval, the regulations governing natural gas-fired power plants’ emissions have become more stringent.    Consequently, the  limitations on some pollutants - including ozone-forming oxides of nitrogen (NO x ) and volatile organic compounds (VOCs) - in the proposed Title V Operating Permit are significantly less than they were under the Plan Approval:   Pollutant Plan Approval Limit (Tons Per Year) Draft Title V Operating Permit Limit (Tons Per Year) Decrease (Tons Per Year) NO X 372 303 69 Carbon Monoxide (“CO”) 2309 657 1,652 VOCs 1251 222 1,029 Formaldehyde (“HCHO”) 8 8 0 All Hazardous Air Pollutants (“Total HAPs”) 22 22 0 Total Particulate Matter (“PM”) 92 95 (3) Coarse Particulate Matter (“PM 10 ”) 92 92 0 Fine Particulate Matter (“PM 2.5 ”) 89 89 0 Sulfur Dioxide (“SO 2 ”) 23 23 0 Sulfuric Acid (“H 2 SO 4 ”) 15 15 0 Ammonium (“NH 4 ”) 194 194 0 Greenhouse Gases (expressed in terms of carbon dioxide equivalent) 3,827,574 3,827,574 0     The reductions in NO X , CO, and VOC emission limits are due to Best Available Control Technology, Reasonably Available Control Technology, and Lowest Available Emission Rate requirements imposed by the Clean Air Act becoming stricter since the Plan Approval was issued in 2015.    To satisfy those requirements today, the plant must meet lower emission limits for NO X  (that were imposed by regulation) and run an oxidation catalyst for CO and VOCs, whereas in 2015 (at least arguably) it did not need to.   What It Means & How to Submit a Public Comment “This shows how the Clean Air Act works in the background to drive improvements in air quality,” GASP Senior Attorney John Baillie explained. “When there is a lag like this between an initial Plan Approval and an initial operating permit, the improvements can seem sudden and significant.”   That draft is available for public comment through Nov. 3.  You can submit written comments to:    Pennsylvania Department of Environmental Protection Southwest Regional Office 400 Waterfront Drive Pittsburgh, PA 15222 Attn:  Nick Waryanka, P.E., Air Quality Engineer If you submit comments, they should reference permit number TV-65-00990.

Fellow Breathers, some congratulations are in order: Allegheny County Health Department (ACHD) Director Dr. Iulia Vann has been named one of the de Beaumont Foundation's 40 Under 40 in Public Health - a national recognition honoring her exceptional leadership and enduring commitment to improving lives, advancing health equity, and transforming public health systems to serve all communities more effectively.  The de Beaumont Foundation announced the program's Class of 2025 today after reviewing nominations from hundreds of public health leaders across the country.   A distinguished panel of professionals selected the honorees based on their leadership, innovation, and contributions to the health of their communities. Here are the details, courtesy of an Allegheny County news release issued Tuesday: Vann is a distinguished public health leader dedicated to advancing health equity, innovative policy development, and systemic change. As the Public Health Director for Allegheny County, she leads the strategic implementation of the Health Department's priorities including Plan for a Healthier Allegheny , a comprehensive community health initiative addressing physical health, behavioral health, and environmental health. "I am truly honored to be recognized among the De Beaumont Foundation's 40 Under 40 in Public Health. This recognition represents more than my professional journey - it reflects a lifelong commitment to advancing health equity, uplifting communities, and ensuring that every person has the opportunity to live a healthy, dignified life." said Dr. Vann. "Public health is my passion and purpose, and I am inspired every day by the resilience, brilliance, and compassion of those who dedicate themselves to building a healthier, more just world." With an extensive background in public health administration, Dr. Vann oversees multimillion-dollar budgets and large-scale public health operations, ensuring that data-driven, equity-focused policies drive community health improvements. Her expertise spans social justice, health disparities, and federal, state, and local health policy. She has played a pivotal role in addressing emerging health threats, including serving as a Public Health Incident Commander during the COVID-19 response. Dr. Vann holds a Master of Public Health from East Carolina University and a Doctor of Medicine from the University of Medicine and Pharmacy Carol Davila. She is a champion of community engagement, workforce development, and collaborative public health interventions, ensuring that all residents, particularly the most vulnerable, have the opportunity to lead healthy lives. “Huge congrats to Dr. Vann from all of us at GASP,” our Executive Director Patrick Campbell said. “We appreciate her fresh approach to leadership and public engagement and look forward to continuing to work with her and her team to help improve public health here in Allegheny County.”