GEISMAR, La. -- A Louisiana fertilizer plant says it can treat contaminated and highly acidic wastewater to drinking-water standards, and wants a state permit to discharge treated water into the Mississippi River -- the drinking water source for New Orleans and other downriver communities.
PCS Nitrogen Fertilizer LP has shut down a production line that, since the 1960s, has piled up a 180-foot-tall heap of phosphogypsum at its plant in Geismar. That pile is topped by lakes holding an estimated 90 million to 100 million gallons of wastewater -- enough to fill two-thirds of the vast building where NASA assembled moon rockets.
Contaminants include heavy metals, nutrients and trace amounts of radioactive elements.
The company has been barred for decades from letting the water get into nearby waterways. But it is now seeking permission to treat the water at its plant in Geismar, between Baton Rouge and New Orleans, and discharge it into the river, The Advocate reported.
The gypsum might collapse, releasing the contaminated water, if that water is simply allowed to sit in the storage lakes, the company says.
Discharges would have to meet federal standards for drinking water, according to PCS Nitrogen and the state Department of Environmental Quality.
"We are proud community members here in Louisiana and understand our responsibility to care for the environment and public health," Richard Holder, general manager of the plant, said in a statement. Treating the water will benefit the environment and community, he said.
Environmental groups have asked the U.S. Environmental Protection Agency to end a federal exemption and declare the acidic water and gypsum hazardous waste.
PCS Nitrogen's plan is still under consideration. Some environmental groups raised objections during a public hearing and a comment period that ended earlier this month.
Matt Rota and Naomi Yoder, two staff members with Healthy Gulf, and Darryl Malek-Wiley, of the Sierra Club, said the proposed permit didn't consider concerns noted by the EPA when the state renewed the plant's discharge permit in 2015.
The EPA noted that a section imposing federal concentrating limits also lets the amount of phosphorus going into the river rise with the river's flow.
The 2015 permit application also didn't seem to consider effects on drinking water downstream, the EPA said.
The river downstream from Geismar provides drinking water for nearly a million people, including those in Jefferson Parish and New Orleans, the state health department says. Tens of thousands more rely on Bayou Lafourche, which carries water from the Mississippi.
Some environmentalists also worry that phosphorus and nitrogen in the water could worsen the Gulf of Mexico's annual dead zone, in which the nutrients play a major part.
PCS Nitrogen said that since it shut down its phosphoric acid line in late 2018, phosphorus releases into the river fell by 50% and the company expects them to fall to 22% of pre-closure levels by 2023.
The proposed permit still allows sizable releases of both phosphorus and nitrogen, with no or only moderate reductions from earlier permits, the newspaper said.
Treating the water is expected to take two to three years. It will take 20 to 30 years to treat water that gradually seeps out of the pile, the company told regulators.
It said other options, such as injecting the water into deep wells or hauling it to a treatment site, were too costly or posed other risks.
The planned treatment would cost about $20 million, compared with $86 million for trucking the water somewhere else, according to company officials.
PCS Nitrogen is part of Nutrien Ltd., based in Saskatoon, Saskatchewan, Canada.
