Situated east of Everglades National Park, the 60,000-acre Lake Belt region is home to the Biscayne Aquifer’s vast underground network of fresh water reserves that provide 150 million gallons of clean drinking water to some 6.5 million South Floridians every day.
The Aquifer was intentionally built on the remote, half-wild outskirts of Miami-Dade County to ensure that South Florida’s drinking water would remains safe from contamination by development and industry.
In early 2002, however, the U.S. Army Corps of Engineers approved several permits allowing for the mining of limestone on a total of 5,700 acres in the Lake Belt.
Three years later in January of 2003, benzene – a cancer-causing chemical – was detected at a Miami-Dade County water treatment facility. Although benzene emerged as a common household chemical found in everything from shaving cream to industrial lubricant, the EPA officially declared it a hazardous pollutant in 1977 after it was discovered exposure was linked to an increase risk of leukemia 1977.
The legal limit for benzene in drinking water is one part per billion. Samples from Miami-Dade County indicated benzene levels were five times that limit. Weeks later, another well in the Lake Belt registered traces of benzene and was ordered shut down.
Thankfully, Miami-Dade’s water treatment facilities proved fully capable of purifying the water; at no point during the crisis were any customers exposed to heightened levels of benzene.
Nonetheless, the Miami-Dade Water and Sewer Department (WASD) immediately launched a months-long investigation, the cost of which would eventually grow to exceed $1 million. The investigation led them straight to the Lake Belt’s limestone mines.
In order to mine the limestone, four-inch-wide holes were drilled into the ground, filled with explosives, and blown up. Upon further inquiry, the team learned that most of the mining firms were using ANFO — ammonium nitrate fuel oil — of which a small constituent is benzene.
A coalition of environmental groups including Sierra Club, NRDC, and NPCA sued in federal court to halt the limestone mining and protect South Florida’s drinking water, alleging that the Corps of Engineers and the U.S. Fish and Wildlife Service mishandled the permitting process.
Judge William Hoeveler condemned the Corps of Engineers and Fish and Wildlife Service for “failing to carry out their duty” to safeguard the surrounding wetlands and ruled that the conclusions in the original Environmental Impact Statement (EIS) were based on inaccurate industry information. The mining permits for the three companies closest to the wells were cancelled in July of 2007.
In his scathing, 176-page written opinion, the judge wrote that “In three decades of federal judicial service, this Court has never seen a federal agency respond so indifferently to clear evidence of significant environmental risks.” Judge Hoeveler concluded that limestone mining directly contributed to the benzene contamination and pointedly blamed the Corps for failing to address it.
Had the Corps of Engineers carried out due diligence and handled the Environmental Impact Statement properly instead of rubberstamping it, the mining companies would likely have been forced to use alternative explosives from the start and drinking water contamination could have been avoided. Instead, cleanup of the contaminated wells required tens of millions of dollars in needless expense.
The story of Lake Belt is a sobering reminder that when safeguards like environmental reviews mandated by the National Environmental Policy Act (NEPA) are rushed or ignored, the financial, environmental, and public health consequences can be severe.
Many NEPA “reforms” under discussion by President Trump and opponents in Congress threaten the impartiality of this review process. Proposed reforms such as fining already cash-strapped federal agencies for missing permitting deadlines or further delegating environmental reviews to states – many of which are facing their own budget crises – aren’t likely to speed up the environmental review process. The outcome would be more delays or the approval of poorly conceived projects threatening our environmental and public health.
 Sierra Club v. Lt. Gen. Robert L. Van Antwerp, No. 07-13297 (11th Cir. 2008). Available at: https://cases.justia.com/federal/appellate-courts/ca11/09-10877/200910877-2011-02-28.pdf?ts=1411113348
 “Titan’s Florida mining permit canceled by judge.” Star News Online. February 3, 2009. Available at:
 “Poisoned Well.” Miami New Times. March 20, 2008. Available at:
 “Final Supplemental Environmental Impact Statement on Rock Mining in the Lake Belt Region of Miami-Dade County, Florida.” U.S. Army Corps of Engineers. May 2009. Available at: https://books.google.com/books?id=hDk0AQAAMAAJ
 “Army Corps re-permits Lake Belt rock mines.” South Florida Business Journal. January 29, 2010. Available at: