In response to administrative complaints filed with the agency (Nos. 01R-22-R6, 02R-22-R6, and 04R-22-R6), the Environmental Protection Agency (EPA) opened an investigation into the Louisiana Department of Environmental Quality (LDEQ) and the Louisiana Department of Health's (LDH) on April 6, 2022 via its authority under Title VI of the Civil Rights Act of 1964 and EPA's nondiscrimination regulations. The complaints alleged that LDEQ's implementation of its air pollution control permit program was racially discriminatory and that LDH failed in its duty to inform and make recommendations to the public about health threats and air toxics exposures. EPA conducted an initial investigation to assess whether LDEQ's and LDH's actions had an adverse disparate impact on Black residents living in St John the Baptist Parish, St. James Parish, and the state's Industrial Corridor (nicknamed "Cancer Alley"). EPA focused on two facilities known to be emitting chloroprene and other carcinogenic toxins in Reserve and near St. James Parish.

On October 12, 2022, EPA published a 56-page letter of concern sent to the Secretaries of LDEQ and LDH, respectively. EPA officials met with LDEQ and LDH prior to releasing the letter on September 22 and 23, 2022 and the agency opted to release the letter in order to facilitate resolution of the complaints. EPA emphasized that it had not concluded its investigation but had found significant evidence suggesting that LDEQ and LDH's actions or inactions had resulted in disparate adverse impacts on Black residents in all three communities and called the failure to do a proper impact analysis "concerning" from a civil rights perspective.

EPA reviewed pollution data, finding that highest cancer risks from air toxins were almost exclusively within the Industrial Corridor. In addition, the letter criticized a 2018 report issued by LDH that concluded that moving children from an elementary school in an area with high concentrations of toxins to another location would not significantly decrease levels of cancer risk. The letter also noted that LDEQ Secretary Chuck Carr Brown had made inaccurate or misleading statements during public hearings when residents raised concerns about the chloroprene levels. 

Following EPA's letter of concern, the operators of the plants subject to investigation issued press releases defending their permits and operational standards. A state court rescinded one of the plant permits issued by the LDEQ on environmental justice grounds, a decision that both the LDEQ and the company have appealed. 

According to a statement issued on October 13, 2022, LDEQ and LDH are willing to engage in an informal mediation process to resolve the complants.

The investigation remains ongoing.