State environmental regulators won't allow Mosaic Fertilizer to use an abbreviated review process as it seeks to install 12 high-powered fans to evaporate hundreds of millions of gallons of radioactive and acidic water laced with heavy metals from the company's complex in eastern St. James Parish.

Instead, Mosaic must seek a full-blown air permit modification that will require public hearings and a comment period. The review could take months to complete, regulators said.

Officials with the state Department of Environmental Quality also rejected this past week another option Mosaic proposed to remove acidic process water: a plan to truck the hazardous water in 18-wheelers from the Uncle Sam plant near Convent and across the Mississippi River for treatment at Mosaic's Faustina plant in western St. James Parish.

Mosaic says using fans is the quickest and most efficient way to reduce the high levels of hazardous "active water" from storage ponds at the Uncle Sam facility along the Mississippi River. The company had already done site preparation on top of its huge gypsum waste pile for the fans.

Heavy rains last year and the unexpected movement of a wall in the waste gypsum, which supported the company's largest storage lake, forced the company to shift the hazardous water around to other lakes.

Though rainfall at the plant has been largely below average this year, the company has told DEQ it wants to cut water levels by 300 million gallons by Sept. 30 and another 240 million by April 30. 

The fan concept has drawn fire from environmentalists and community groups who contend Mosaic miscalculated how the aerial spraying would spread vaporized water around its site. The modeling failed to show, they say, that contaminated water droplets would fall on local communities on both sides of the Mississippi River, in addition to the surrounding environment.

Mosaic has submitted calculations suggesting that while people on or near the plant might breath in radioactive materials in the water, it would be at levels that are considered safe. The fans would also release hydrofluoric acid, which also drew concerns from community groups.

Mosaic had sought approval to install the fans through a variance, but Elliott Vega, assistant secretary of the DEQ Office of Environmental Services, said Friday that the fan proposal continued to raise concerns from environmental groups and the agency, including what the possible exposure pathways for the water's contaminants would be if spraying did happen.

"The scale of this thing just is … was never really something that would be considered normal variance material," Vega said.

He said a variance might more commonly be applied to the use of an emergency flare for a few days because a piece of equipment went down.

Vega sent Mosaic a letter Tuesday informing the company of his decision on the fans and then another letter on Thursday about the trucking plan, which ran into concerns about the trucking logistics and legal constraints on discharging the hazardous water after it is treated.

Dozens of trucks would have traveled local highways daily moving the water.

While the letter on the trucking option specifically rejects that idea, the letter on the fans doesn't.

"If Mosaic wishes to utilize evaporators for on-site water management, it will need to submit an application for a major modification to its current air permit," Vega wrote in the Tuesday letter. 

Mosaic officials said they will pursue the permit modification, saying the data they have gathered show emissions would be "below ambient air quality and occupational health standards set by regulators to protect human health and the environment."

"(DEQ's) feedback on this matter is appreciated, and the company will continue to work with the agency on water inventory management options," said Callie Neslund, a Mosaic spokeswoman.

Environmentalists welcomed DEQ's decisions on both options, but especially the fans.

"I am very happy that the (DEQ) stopped one of the craziest ideas that I have ever come across in my years as an environmentalist, spraying radioactive wastewater into the air and hoping that nobody got hurt," said Darryl Malek-Wiley, a senior organizer for the Sierra Club's environmental justice and community partnership program.

The Tulane Environmental Law Clinic, which represents residents in the area, submitted comments to DEQ about the fan proposal and posed questions about what the group saw as unexplained discrepancies in the company's air modeling.

Lisa Jordan, director of the law clinic, said that online databases show DEQ had begun asking Mosaic to explain some of those questions shortly before the letter Tuesday about the proposed fan variance. She welcomed DEQ's decision as the right call. 

In both letters, DEQ has urged Mosaic to pursue underground injection of the hazardous water as soon as possible, by drilling a new hazardous well and reusing old oil and gas wells on site. Vega said that if Mosaic were to pursue the latter option, it would have to treat the process water first before injecting it underground.

Mosaic's own estimates have shown the deep-well injection wouldn't remove as much water as quickly as the fans, but Neslund said the company would also pursue the wells.

"Below average rainfall to date and progress on water inventory management at the Uncle Sam facility have put the company in a better position on water inventory today compared to when reduction efforts began months ago," she said.


Email David J. Mitchell at dmitchell@theadvocate.com

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