Bayou Verdine cleanup work reaches midway point

By By Frank DiCesare / American Press

Cleanup work along Bayou Verdine has reached its midway point, as dredging continues along its upper region where environmental

contaminants are being removed.

Construction workers have been dredging the area since April, removing contaminated sediments and pumping the slurry to an

impoundment on Phillips 66’s property next to Trousdale Road.

Built in April, the impoundment holds

the contaminated sediments after the water has been removed from the

slurry, a process

known as “dewatering.” Once the slurry has been dewatered, the

clean water is discharged back into the bayou, said Casey Luckett

Snyder, EPA’s Region 6 project manager.

When the dredging work is finished, the

remaining sediments in the impoundment will be capped with soil.

Testing will be conducted

to confirm that the solidified sediments have reached the required

strength to support the soil cover, Snyder added.

“The sediments in the bayou will be

dredged between 1 and 2 feet,” she said. “The slurry is piped to the

impoundment; the

contaminated sediments fall out via gravity and the water that is

coming with that slurry sits on the top and then moves trough

a baffle system. (The water) is then tested prior to being

discharged back into Bayou Verdine.”

Snyder said the water is tested for

compliance with Phillips 66’s Louisiana Pollutant Discharge Elimination

System permit.

If for any reason the tested water does not meet LPDES

requirements, she added, it is passed through a sand filter and

recirculated

back to the impoundment and the process starts over again.

“So far that hasn’t happened yet,” she said. “So far all of the testing of the discharged water has not had to run through

the secondary sand filters.”

In a statement to the American Press, Janet Grothe, Phillips 66’s senior adviser of health, safety and environment, said numerous controls are in place “to ensure

that there is no uncontrolled releases of water from the impoundment.”

“The treatment system for the water has automated monitoring devices to assure the discharge criteria is met, and several

valves that are closed automatically if power is lost,” Grothe said.

“The dike walls of the impoundment were built to withstand a major storm, as demonstrated in September when the site had 10.84

inches of rain in one 24-hour period and the water and sediments never came close to overtopping the impoundment.”

The bayou’s cleanup efforts stem from a

2011 federal consent decree the U.S. Environmental Protection Agency

signed with Phillips

66 and Sasol. The companies agreed to be responsible for

addressing contaminated sediments. EPA officials, with support from

the state Department of Environmental Quality, are overseeing all

cleanup activities in the bayou.

Snyder said dredging work will continue in the bayou south of the Interstate 10 bridge once the upper region is complete.

Sediments in Bayou Verdine have been contaminated by polynuclear aromatic hydrocarbons and heavy metals such as zinc, copper

and chromium. Snyder said none of these contaminants pose a risk to human health. She added, however, that they do pose a

significant risk to the environment.

Dredging along Bayou Verdine is scheduled for completion in April. Impoundment closures are expected to take about eight months.

Once cleanup activities are done, work will begin on site restoration.

“It’s obviously a bit of an invasive procedure in the bayou,” Snyder said. “So workers will have to do some site restoration

along the bayou in areas where they had to acquire access to get to the upper regions.”

In a statement to the American Press,

Joe Ledvina, special projects manager for Sasol, said the company is

“pleased to see the positive progress of this collaborative

effort” to clean up Bayou Verdine.

“The companies and the regulatory agencies are working toward a common goal,” Ledvina said, “which will benefit our environment

and our community for many years to come.”