Piney Point Enters a New Chapter

Located near the mouth of Tampa Bay, Piney Point was originally built to take advantage of its location adjacent to Port Manatee. Above, The oldest and smallest pond at Piney Point has been drained and workers are installing a new liner; notches will be cut in each of the closed ponds so they never hold large amounts of water again. Photo courtesy Florida Department of Environmental Protection

Piney Point, the abandoned phosphate plant that has dumped more than a billion gallons of contaminated water into Tampa Bay over a 60-year period, may finally be turning the corner. “This is the final chapter,” said John Coates, program manager for the Florida Department of Environmental Protection’s Mining and Mitigation Program. “This is the closure of this facility, once and for all.”

By Vicki Parsons, originally published September 16, 2022

Piney Point has been problematic almost since it was built in 1966. Spills began in the 1970s, highlighted by a 10-million-gallon release in October 2001 that carried 16.2 tons of nitrogen, among other contaminants, into lower Tampa Bay, which was more than three times the annual nutrient budget for that bay sector.

After the 2001 release, more than 200 million gallons of water was removed from the site to prevent future releases. HRK Holdings purchased the property to develop as an industrial park, but then allowed Port Manatee to use the empty gypsum stacks to store dredged material. The liner apparently wasn’t designed to hold that much sediment and ripped. Just months after dredging began in April 2011, another 169 million gallons of water was released in an emergency discharge to relieve pressure on the dikes.

After steady increases over the last decade, water levels increased to the point where another leak in the containment system required managers to release 215 million gallons of wastewater in 2021 to prevent an entire pond from collapsing. Most researchers believe that the release contributed to Tampa Bay’s worst red tide in 50 years, which resulted in massive fish kills as far north as Hillsborough and Old Tampa bays.

This isn’t the first time that the state has tried to close Piney Point, though. “This sounds exactly like the plan from nearly 20 years ago,” said Suzanne Cooper, environmental planner for the Tampa Bay Regional Planning Council at the time.

Moving Forward

The two major releases came from NGS-S (New Gypsum Stack-South), the largest pond at Piney Point. OGS-S (Old Gypsum Stack-South) is now being closed. Graphic courtesy Florida Department of Environmental Protection

Assuming all goes as planned, the gypsum stacks that tower over Bishop Harbor will become a stormwater system by the end of 2024. The first step is draining nearly 500 million gallons of water from four ponds so liners can be installed, then covered with two feet of soil and vegetation to protect them from UV rays and temperature extremes. Properly installed and maintained, the liners should last more than 50 years.

Wastewater is injected deeper than aquifers used for drinking water. Photo courtesy Wikipedi

For now, there is enough storage on the site to accommodate at least 27 inches of rain before water would need to be released to protect the decades-old dikes, said Herb Donica, the court-appointed receiver directing the site’s closure.

Parts of the site, including properties adjacent to U.S. 41, are expected to be sold and developed. The future of the stacks themselves is less clear. HRK still owns the gypsum stacks but they will be expensive to manage, Donica said. He made it clear that the stacks will not be developed and is hopeful that they can be repurposed as a wildlife refuge in the future. Some beach-nesting birds already are utilizing parts of the site, notes Mark Rachel, Audubon Florida’s coastal island sanctuaries manager.

About 594 million gallons of the water will be treated and injected into a 3,000-foot-deep well under the Floridan Aquifer that supplies much of the state with drinking water. An onsite water treatment plant will remove suspended solids and reduce nutrients to maintain the performance of the well. Radiological testing consistently shows that it is below drinking water standards.  

The treatment plant and well should be up and running by mid-2023, Donica said. Manatee County Utilities is trucking about 100,000 gallons per day — 34 million gallons so far — to its nearby wastewater treatment plant, and then selling it as reclaimed water. A spray mist system also continues to operate, speeding evaporation from the ponds.

Construction is underway now on the first pond to close the first pond, OGS-S, one of the oldest and smallest ponds. About 4.5 million gallons of water was released, but it was stormwater, not water used to process the phosphate, Donica said. “We tested it continuously. The total nitrogen ranged from about 2.3 to 3.5 parts per million – about one-tenth of one percent of what the guidelines call for.” (The guidelines are the federally adopted maximum daily loads for Lower Tampa Bay.)

The legislature already has budgeted $100 million from federal COVID relief funds for the clean-up but more funding is likely to be necessary based on rising construction costs. FDEP has sued the current landowner, HRK Holdings, although the company filed for bankruptcy following the 2011 spill. “We have every intention of holding HRK accountable,” said Mark Rains, chief science officer for the state. “This is just not being hung around the taxpayers’ necks. We do have plans in place and in action to hold HRK accountable to the greatest extent possible.”

Piney Point: Problematic for More Than 50 Years

1966

Borden Chemicals builds a plant near Port Manatee to process phosphate rock into fertilizer at the request of county officials.

1970

Polluted water is dumped into Bishop Harbor resulting in fish kills.

1989

A 23,000-gallon leak of sulfuric acid from a holding tank forces the evacuation of hundreds of people, including Port Manatee workers.

1991

Two air releases of sulfur dioxide and sulfur trioxide.

1993

Mulberry Corporation purchases the Piney Point facility from Royster Phosphates, Inc. after Royster declares bankruptcy.

January 2001

Mulberry Corp. contacts DEP to say that financial difficulties will prevent it from assuring environmental security at its Polk County and Piney Point plants; abandons plants 48 hours later.

February 2001

DEP takes over with initial $4 million in state emergency funds, most of which is needed to pay for electricity that keeps the pumps and treatment systems working.

November 2001

DEP authorizes emergency discharges into Bishop Harbor following Tropical Storm Gabrielle; 10 million gallons of partially treated wastewater released to prevent total collapse of dikes.

January 2002

Agency on Bay Management forms a task force to develop alternatives to discharging partially treated wastewater from site.

January 2003

Site now holds 1.4 billion gallons of water and can only accommodate another 2.5 inches of additional rainfall.

February 2003 to 2004

Overflowing ponds are dumped into Bishop Harbor, causing an algal bloom. The U.S. Environmental Protection Agency allows managers to barge Piney Point wastes out into the Gulf of Mexico.

September 2006

HRK Holdings purchases Piney Point to develop industrial lands around it, but allowed Port Manatee to use the stacks to store dredged material instead.

February 2007

Storage capacity at 90+ inches of rainfall; 2.35 million gallons of water removed using multiple methods but 73% was treated water released into Bishop Harbor. All together, an estimated 1.1 billion gallons of water had been discharged into Lower Tampa Bay.

January 2011

Closure construction complete; 1.3 billion gallons of lined storage available in closed reservoirs.

April 2011

Dredging for Port Manatee berth 13 begins; dredged materials are pumped to the Piney Point facility.

May 2011

A leak is found in the dike wall and stormwater ditch; another 170 million gallons of water are released in an emergency discharge to relieve pressure onsite.

June 2012

HRK files for bankruptcy.

February 2020

After steady increases beginning in 2018, water levels increase to the point where there is less than 10 inches of capacity remaining.

April 2021

Another leak in the containment system causes the emergency release of 215 million gallons of wastewater to Bishop Harbor in Lower Tampa Bay.  Nearby residents and the jail are evacuated over concerns that the entire dike could fail.

May 2021

Tampa Bay’s worst red tide in 50 years causes fish kills as far north as Hillsborough and Old Tampa bays. Researchers believe that nutrients released from Piney Point contributed to the naturally occurring harmful algal bloom.

March 2022

DEP issues an order approving the conceptual closure plan for Piney Point

June 2022

FDEP approves closure design for one of the oldest and smallest ponds, OGS-South, which contains primarily stormwater.

Mid-2023

Anticipated completion of on-site wastewater treatment plant and deep-injection well.

December 2024

Anticipated closure of OSG-North and NGS South.