Federal officials have not yet made public the list of hazardous materials present at a Tangipahoa Parish petroleum products plant that caught fire and exploded last month, saying that doing so might reveal “confidential business information.”

The Environmental Protection Agency, which has led disaster response efforts and all public communications since the Aug. 22 incident, has known for weeks which specific hazardous and radioactive materials were present at Smitty’s Supply Inc. in Roseland. After the Illuminator repeatedly requested information about the materials, the EPA acknowledged it had such a list but refused to provide a copy, saying the agency needed to first clear it with Smitty’s Supply.

“On Aug. 27, Smitty’s, through its legal counsel, provided EPA with an inventory list of their products and materials at their facility near Roseland,” EPA Press Officer Kellen Ashford wrote Friday in an email. “EPA has worked with Smitty’s to verify the accuracy of the list. However, a question remains on whether the list contains Confidential Business Information (CBI).”

The EPA said it is following federal laws that prohibit the public release of confidential business information or what could be considered trade secrets, which are exempt from disclosure under the Freedom of Information Act and other laws.

Ashford said the agency has asked Smitty’s Supply whether its inventory list should be considered confidential.

“We are currently waiting for their response,” he said.

Records the Louisiana Department of Environmental Quality has posted on its website list some of the chemicals at Smitty’s Supply, but it’s unclear if it’s a comprehensive list. The state agency also doesn’t distinguish whether the listed chemicals were involved in the fire.

Corinne Gibb, a chemist who works with the Louisiana Bucket Brigade environmental advocacy group, said it seems like the EPA is making more of an effort to keep the inventory list from the public than Smitty’s Supply.

“Every action they are taking makes it suspicious,” Gibb said. “Why would they not ask on day one if it was confidential? Also, surely when the population is sprayed with the content of the inventory, surely the EPA’s duty at this stage is to inform the population as soon as they received the information. It definitely seems to lack transparency.”

The Illuminator’s calls and emails to Smitty’s Supply have gone unanswered.

Oily residue covered surrounding homes, farms and businesses from the Aug. 22 fire, which took two weeks to fully extinguish. Cleanup crews have so far recovered 5.6 million gallons of contaminated material from the site and nearby waterways such as the Tangipahoa River, according to the EPA.

Louisiana Department of Environmental Quality records mention some of the hazardous materials known to be on site, including naphthalene, xylene, ethylene glycol and phosphoric acid, all of which have applications in the automotive industry. The state agency has ceded authority to the EPA for the government’s response to the fire.

Estimates of the cleanup costs associated with the Smitty’s Supply fire have climbed past $39 million, according to state records. The company is responsible for covering the expense.

EPA adjusts allowable pollution levels for fire
The EPA has said repeatedly the pollution from the Smitty’s Supply explosion and fire poses no imminent danger to the public.

The agency notes its fine particulate matter readings were below the special levels threshold it established specifically for the incident — 300 micrograms per cubic meter of air — but it has not said how or why it established that limit, which is much higher than standard pollution allowances.

Gibb said she’s never heard of a threshold being set that high before.

For emergency incidents, fine particulate matter over 250.5 micrograms in a 24-hour period are considered hazardous, according to the EPA’s air monitoring guidelines for fires.

Toxic fine particulate matter, even during short exposure periods, can lead to heart attacks, asthma attacks, cancer and other health risks, according to an EPA fact sheet. The agency has regulated particulate matter pollution since 1971 and has revised its standards four times since then.

Gibb said the 300-microgram threshold for the Smitty’s Supply fire is more than 30 times higher than the EPA’s normal safety threshold. She noted air monitoring readings far exceeded normal standards several days following the explosion.

Mobile air monitoring readings outside the facility reached a high of 250 micrograms two days into the fire, according to the data on the EPA’s incident website for Smitty’s Supply.

After the Aug. 24 reading, the EPA paused its mobile air monitoring for nearly 10 hours. Typically, the air monitors take readings roughly every five minutes. When asked about the 10-hour gap, the agency said the air monitors needed to be recalibrated. Other interval gaps in the monitoring data prior to that one lasted around four hours, the EPA website shows.

“Real-time air monitoring requires frequent calibration of instruments due to changing environmental conditions,” Ashford said. “During the active firefighting operations at the site, site conditions changed that resulted in changes to the air monitoring activities, which created time intervals where air monitoring was not active.”

Water testing reveals toxins
Water samples the EPA collected from a pond and a ditch near the facility showed elevated levels of polycyclic aromatic hydrocarbons, according to a lab report the EPA initially posted on its incident site. PAHs, as they are more commonly known, are produced when fossil fuels are burned. They have been linked to a range of health disorders, including cancer and blood and liver abnormalities, according to the U.S. Centers for Disease Control and Prevention.

The water samples also contained elevated levels of heavy metals including arsenic, barium and lead, the lab report said. The levels were higher than what’s allowed in drinking water, though it’s unclear whether the EPA used a different threshold for its water sampling.

Susan Richardson, an analytical chemist from the University of South Carolina who reviewed the findings, said the lack of information and adequate sampling makes it difficult to truly assess the risk to the community.

“What was deposited in the water in that ditch could be indicative of what was in the air and what could be deposited on the ground and other surfaces (homes, vehicles, etc.),” Richardson said.

Industrial X-ray machine still missing
EPA, through its public statements and online hub site, also did not publicly disclose that five fill-level gauges containing radioactive material were present at the facility. Officials said all have been recovered and were undamaged, but a team of radiation inspectors spent two weeks searching for what they thought was a missing sixth gauge. On Friday, the EPA realized a mistake had been made and that the missing device was actually an industrial X-ray machine.

The material in the gauges is Americium 241, a manmade radioactive isotope that is a byproduct of nuclear reactor fission. It is also used in minute amounts in household smoke detectors. It emits alpha and low-level gamma radiation that can penetrate the human skin, but Americium 241 is typically only harmful after prolonged exposure or when ingested or inhaled, according to the CDC.

State officials notified the Nuclear Regulatory Commission about the situation at Smitty’s Supply Aug. 26 and reported each gauge contained 100 millicuries of Americium 241 — more than a thousand times the amount found in smoke detectors.

Officials initially thought there was a sixth gauge missing but gave up looking for the purported sixth gauge on Sept. 11, state records show.

“As there was no risk of exposure to the public from the five devices containing radioactive materials, EPA continued response operations,” EPA press officer Edward Mekeel said in an email.

About a week later, the EPA learned from Smitty’s Supply that an X-ray machine, and not another gauge, was missing. X-ray machines only produce radiation when they are in use.

“The devices and X-ray machines look similar,” Mekeel said.