Hurricane Milton threatens Florida’s phosphate waste sites

Hurricane Milton, hitting Florida’s west coast with Category 3 ferocity, raises alarm over the potential dispersal of toxic waste from the state’s sizable phosphate fertilizer industry. As the storm unleashes powerful winds and heavy rainfall, over a billion tons of phosphogypsum—a slightly radioactive byproduct from phosphate ore processing—are under threat of being washed from storage “stacks” into surrounding ecosystems.

These stacks, massive and pond-like, house the waste near large phosphate mines and fertilizer plants, primarily in central Florida, directly in Milton’s projected path. “These sites are essentially ticking time bombs, given their proximity to major waterways and the heightened risk of storm damage,” warned Ragan Whitlock, a staff attorney at the Center for Biological Diversity.

Phosphogypsum contains radium, which decays into radon gas, and potentially toxic heavy metals, raising significant health and environmental concerns. The inability to dispose of this waste permanently means it continues to accumulate, making it increasingly vulnerable to hurricanes like Milton.

Recalling past incidents, Hurricane Frances in 2004 released 65 million gallons of acidic wastewater from these stacks into nearby waters, resulting in massive aquatic fatalities. Now, Hurricane Milton, with its 120 mph winds and extensive storm surge, threatens a repeat of such environmental disasters.

One site of concern is the Piney Point wastewater reservoir, known for structural weaknesses and past leaks, including a significant breach in March 2021 that led to massive fish kills in Tampa Bay. The site’s ongoing management issues, exacerbated by the bankruptcy of its former owner, pose additional risks during severe weather events.

The Mosaic Company, a major phosphate producer, has multiple vulnerable sites, including two at its Riverview facility on Tampa Bay and others inland. A 2016 incident at Mosaic’s New Wales Gypstack saw a sinkhole release millions of gallons of polluted sludge into Florida’s primary drinking water source. Despite assurances from Mosaic of no offsite impacts and extensive storm preparations, concerns remain about the structural integrity of these sites under hurricane conditions.

As the storm advances, both Florida and federal agencies are mobilizing to mitigate its potential impact on these hazardous sites and the broader environment. The state’s Department of Environmental Protection is securing critical facilities and natural reserves, while the EPA focuses on safeguarding Superfund sites like the Stauffer Chemical Co. on the Anclote River, a former pesticide production site undergoing extensive cleanup.

With Florida playing a critical role in the U.S. phosphorous supply, essential for agriculture and munitions, the repercussions of Milton’s passage could extend beyond environmental damage, affecting industrial and national security interests.