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EPA in Louisiana

LaPlace, Louisiana - EPA Response

EPA Actions

EPA's 2011 National Air Toxics Assessment (NATA), a screening-level assessment, for the United States was released in December 2015 and estimated higher than expected levels of chloroprene in the community of LaPlace, LA. Over the last several years, EPA has taken actions to investigate and understand air quality in LaPlace, as summarized in the timeline below.


  • EPA verified the modeled emissions data used in the 2011 assessment with the facility owners, DuPont and Denka Performance Elastomer (DPE) prior to releasing the 2011 NATA.
  • EPA issued an information request to DPE on December 18, 2015 to gather information to validate the facilities emissions inventory submittals and evaluate compliance with their Title V air permits.
  • EPA shared the NATA results with the Occupational Safety and Health Administration to allow them to evaluate whether an investigation of worker exposures to chloroprene at the facility was needed.
  • EPA also conducted verification modeling and assessment using more recently available air monitoring information from the 2014 Emissions Inventory data. The refined modeling effort can be utilized to attribute concentrations of chloroprene within the community back to emissions source(s) and calculate source attribution.  The verification modeling generally confirmed the assessment noted in the 2011 NATA.
  • Since the release, EPA and the Louisiana Department of Environmental Quality (LDEQ) have been working closely with DPE representatives to fully assess actual conditions near the Pontchartrain facility in the community of LaPlace, LA. 
  • In preparation for air sampling, LDEQ conducted an initial air monitoring survey on six days between March 1 through March 10, 2016. LDEQ collected 25 grab samples from different locations in the community of La Place. The samples detected chloroprene and indicated the need for additional monitoring in the community.
  • During the same period, EPA collected a total of twenty samples, up to 24-hour in duration, from five different locations within the community of La Place. EPA sampling results confirmed LDEQ's findings and the need for additional air monitoring in the community.
  • EPA conducted a site visit at DPE on May 18, 2016 to gather information on the processes and air pollution controls at the facility. The information gathered is being utilized to develop an information request to require additional emissions testing at the facility as part of the Agency's risk and technology review of the Polymer Air Resins I MACT.
  • EPA and LDEQ developed a long-term air monitoring plan to measure chloroprene at several locations in the community of La Place. View the latest air monitoring data.
  • EPA's National Enforcement Investigation Center conducted a focused Clean Air Act inspection the week of June 6 - 10, 2016 at the Chloroprene Unit, the Neoprene Unit, and the HCI Recovery Unit to evaluate compliance with the Clean Air Act MACT standards and permit requirements and to identify potential unregulated sources of chloroprene emissions.
  • In June 1016, EPA developed a comprehensive document called the St John the Baptist Action Plan. The action plan served to inform interested parties and report the status of planned activities in the community. The action plan also includes a brief historical background of the Denka plant and specific activities by EPA and LDEQ to address the chloroprene emissions from the plant. EPA's Action Plan for LaPlace, Louisiana.
  • In March 2020, EPA deployed a network of six SPod air monitors around the Denka facility.  These new monitors are projected to provide a better understanding of the frequency and magnitude of chloroprene emission spikes and may help identify possible actions to further reduce chloroprene in the community.  Results from the air canister samples collected by the  SPod monitoring system will be posted when they become available.