Benzene release greater than first reported
What was initially believed to be about a 10-pound release of benzene June 14 at the ExxonMobil Chemical Plant in Baton Rouge, could be as much as 28,700 pounds by the time the chemical cleanup is complete, according to a required incident report from the company.
The state Department of Environmental Quality began an in-depth investigation Thursday after receiving the company’s report late Wednesday that showed the amount of benzene and several other chemicals released during the June 14 incident were much higher than originally believed.
Part of the investigation will involve when ExxonMobil Chemical Plant officials found out the actual levels of chemicals released compared to when those officials relayed that information to DEQ, said Cheryl Nolan, DEQ assistant secretary of the office of environmental compliance.
“Part of what we’re investigating is when did they know what,” Nolan said. “We were disappointed in how it went down.”
Nolan said if DEQ had known the scope of the spill of benzene-containing naphtha on June 14, or if air monitoring outside the facility had shown anything of concern, the response from DEQ would have been more robust.
Initial estimates of releases are usually inaccurate as facilities work to get information out within a short time, said Chris Piehler, DEQ’s inspection division administrator. However, as the situation changes or more information is known, it’s required that those changes be reported to DEQ, he said.
The question of why there wasn’t a better estimate from the facility about the several hour leak and the amount that could flow from the tank during that time span hasn’t been answered yet.
“We have that same question,” Nolan said.
The leak began at 1:54 a.m. June 14 at a failed bleeder plug on a tank and was discovered by operations personnel at 4:35 a.m., according to a timeline from ExxonMobil.
The leak was stopped at 5 a.m. The tank contained “steam cracked naphtha” which has a number of different components, including benzene.
The U.S. Environmental Protection Agency classifies benzene as a known cancer-causing material.
Initial reports indicated that the release would likely be above the required reporting level for benzene, which is 10 pounds.
“We were operating under a 10-pound scenario,” Nolan said.
DEQ staff did air monitoring Thursday around the outside of the facility’s fence line and didn’t find anything of concern, Nolan said. Those results matched ExxonMobil’s air monitoring results.
Then Friday, DEQ received an email from the environmental group Louisiana Bucket Brigade, expressing concern about the release. Nolan said she responded that the release was reported as 10 pounds of benzene, and air monitoring didn’t show any reason for concern.
Then on Saturday, Nolan said, DEQ received another email from the Louisiana Bucket Brigade that said community members were smelling odors and people were getting severe headaches.
“I was in the neighborhood on Thursday with two EPA officials,” said Anna Hrybyk, program manger of the Louisiana Bucket Brigade.
She described a burning oil type of scent and said she had a headache.
“Both of the EPA officials covered their nose and ran to their car,” she said.
In addition, the email Hrybyk sent Saturday said, “Workers report that approximately 700 barrels of naphtha have been released into the sewer system of the plant.”
“They knew how much left that tank by 5 a.m.,” Hrybyk said about ExxonMobil.
Nolan said based on that complaint, which is the only one DEQ said it received, more air testing was done inside the plant and around the fence line.
Except for a location inside the plant where the separation of wastewater and spilled material was being done and workers were wearing protective clothing and respirators, the rest of the air monitoring results showed no levels of concern, said Peter Ricca, emergency response manager with DEQ.
According to the ExxonMobil report, about 400 workers were tested on the day of the leak for potential exposure.
“ExxonMobil believes that none of these individuals will have any adverse impacts,” the report states.
On Saturday, Nolan said, ExxonMobil increased the estimate of benzene release to possibly 1,300 pounds.
ExxonMobil’s staff met with DEQ Monday and said they realized Sunday that there was a lot more material released than they originally thought. However, Nolan said, ExxonMobil staff said they were still not finished with their estimates.
The final estimate of emissions — beginning when the leak started June 14 and ending with the treatment of the material in the wastewater treatment plant — is 28,688 pounds of benzene, 10,882 pounds of toluene, 1,110 pounds of cyclohexane, 1,564 pounds of hexane and 12,605 pounds of volatile organic compounds, according to ExxonMobil’s report.
Stephanie Cargile, public and government affairs manager with ExxonMobil in Baton Rouge, said the company’s staff was able to confirm that 411 barrels of liquid had been released to the wastewater treatment system, but the estimate on how much material vaporized into the air took longer.
“We performed engineering calculations from samples taken during the incident response. This process helped to improve emission estimates reported throughout the next few days,” Cargile wrote in an email. “We are working with LDEQ to address their inquiry about the timeframe in which the initial estimated emissions were reported.”
Cargile said air monitoring inside and at the fence line of the facility will continue for “as long as necessary to ensure the safety of our workforce and neighbors.”
Nolan said the investigation from DEQ will look into how the spill occurred, how the material traveled through the facility’s wastewater system, and its impact to the air, water and waste stream. That information will be compared to the permits at the facility.
The length of the DEQ investigation will depend on what is found and what other questions come up during the course of the investigation, Piehler said.
Nolan said it’s important for the community to call DEQ when they suspect or know something is going on at a facility because it helps trigger additional action from the agency, particularly when there is a concern about air quality. Unlike a water quality issue where samples can be taken, it’s much hard to get samples of a potential problem with something as mobile as air, she said.
“Our response is very dependent on accurate information provided by facilities,” Piehler said, but it can also be informed by other clues to what’s going on such as through complaints or reports from the public.
To report environmental concerns call 219-3640 or (888) 763-5424 Monday through Friday from 8 a.m. to 4:30 p.m. After business hours, call 342-1234 or (888) 763-5424.