Expert raises concerns over ExxonMobil’s Baytown Olefins Plant expansion

An expert on emissions from petrochemical plants testified last month that a permit ExxonMobil is seeking in order to expand the company’s Baytown, Texas chemical plants fails to meet “emission limits similar to what are found in other TCEQ-issued permits for similar sources.”

In September of 2022 ExxonMobil applied to the Texas Commission on Environmental Quality (TCEQ) for a permit to build a new ethylene unit at the Baytown Olefins Plant, which produces chemicals used to produce plastic packaging and other products. The permit, which TCEQ has proposed granting, would allow ExxonMobil to increase greenhouse gas emissions by up to 1,453,293 tons per year, as well as increasing hazardous air pollution in the local community. In November of that year, attorneys with the Environmental Integrity Project filed a request on behalf of Environment Texas and two of our members in Baytown, Texas asking state regulators to take a close look at ExxonMobil’s proposed expansion. 

In September of 2023, a judge with the Texas State Office of Administrative Hearings ordered ExxonMobil to face a contested case hearing over its application, also ruling that Environment Texas and its members who live in Baytown are affected by Exxon’s air pollution enough to be granted “party status” in the hearing. The state administrative law judge will hold a hearing on Dec. 18-19 to determine whether or not the Texas Commission on Environmental Quality (TCEQ) should grant the permit.

In testimony submitted to the judge ahead of the hearing, Robert Jackson–a high-performance computational engineer with over 25 years of experience in the utility and petrochemical industries–raised several critical concerns regarding ExxonMobil’s proposed expansion of the Baytown Olefins plant in Texas. Jackson holds a Bachelor of Science and a Master’s Degree in Mechanical Engineering, and has extensive experience in the process industry with expertise in fuels analysis, combustion, combustion modeling, and emissions. 

The primary purpose of Jackson’s testimony was to assess whether ExxonMobil’s proposed expansion project is utilizing the best available technologies to control and measure certain emissions. One of Jackson’s biggest concerns was on flare emission documentation. Jackson asserted that ExxonMobil had failed to document and include in their submitted emissions modeling potential flare emissions resulting from the proposed expansion. He argued that ExxonMobil should document and include potential flare emissions, considering the variability in destruction efficiency under different conditions, and that the Texas Commission on Environmental Quality (TCEQ) should also consider flare emissions in their estimated overall emissions.

In his recommendation, Jackson emphasized the availability of advanced sensor technology certified by the EPA for monitoring flare performance. He suggested that ExxonMobil should utilize these technologies to continuously monitor flare emissions during major flaring events. Jackson also raised concerns about the allowable limits on particulate matter emissions from the proposed cracking furnace, emphasizing that permit limits should be based on ExxonMobil’s own stack test results from existing furnaces, ensuring consistency with their demonstrated capabilities.

Jackson additionally criticized the ammonia and fuel sulfur content emission limits in the draft permit, noting that other recently issued permits impose lower short-term limits on both. He recommended that the draft permit should align with other similar permits, setting lower short-term ammonia emission limits and fuel sulfur content to enhance environmental protection.

This expert testimony demonstrates that TCEQ erred in proposing to grant the permit. Exxon and TCEQ should go back to the drawing board and put together a proposal that follows the law and protects the community from pollution.