TURNING TO WELLS
FPL WANTS INJECTION WELLS AT TURKEY POINT, WHICH COULD ALSO HELP ADDRESS MIAMI-DADE’S WASTEWATER WOES
Miami-Dade County has to find a place to send millions of gallons of wastewater it now pipes into the ocean. Florida Power & Light has been working for years to contain a saltwater plume beneath the troubled cooling canal system at its Turkey Point nuclear power plant.
A partial solution to both those longstanding environmental problems may reside about 3,000 feet below the sprawling plant on the edge of southern Biscayne Bay — if Florida’s Department of Environmental Protection gives the green light.
FPL is seeking permission to install what are known as injection wells on the property. If the two wells are approved, FPL would switch from tapping a brackish underground aquifer to run through the cooling towers of a natural gas-powered unit on the site and instead use treated Miami-Dade wastewater — helping the county meet its federally mandated 2025 deadline to stop dumping its wastewater in the ocean.
FPL would then take that leftover cooling water and inject it thousands of feet underground, deep below the water South Florida uses for drinking, into an isolated geological pocket known as “the boulder zone.” That leftover aquifer water, with a higher concentration of salt, is now sent into a 5,600-acre system of canals that cool the two nuclear units on the site but also have been blamed for an underground salt plume that could taint underground fresh water supplies.
The utility is three years into its 10-year cleanup process for the saltwater plume, and the latest report suggests its strategy is working: the plume is smaller and doesn’t extend as far west, where its leading edge threatened well fields drawing drinking water from the shallow Biscayne Aquifer.
Miami-Dade still has a ways to go to meet its federal deadline, but diverting millions of gallons of its wastewater to Turkey Point is an attempt to address two problems at once.
Environmentalists seem tentatively on board with the plan, at least as an improvement to the status quo.
“On the one hand, it’s about levels of better. It might be better than putting wastewater into the ocean, but on the other hand, it’s not using this water for anything beneficial. Instead, we’re sticking it into the ground,” said Rachel Silverstein, Miami Waterkeeper.
“And the risk is that it could always leak.”
“The downside for me is that they didn’t seize this opportunity to do more.”
A SCALED-DOWN SOLUTION
The notion of using Miami-Dade’s wastewater at Turkey Point has been around for years, ever since FPL proposed building two new nuclear reactors at its bayfront plant. The utility needed a whole lot more water to cool down the potential new reactors, and a new way to handle it after its 50-yearold cooling canal system proved problematic.
The mutual solution would have allowed Turkey Point to use 50% of Miami-Dade’s wastewater, almost completely meeting the county target
of re-using 60% of its water by 2025. And it would have allowed FPL to use freshwater in its cooling canals, combating the saltwater plume.
But then, the cost estimates came out. The price to clean Miami-Dade’s wastewater enough to use it in the leaky canals was higher than anyone was interested in paying, so the idea fizzled. And FPL indefinitely paused its plan to build two new reactors.
“Municipal wastewater has a lot of pollutants in it, and also high nutrients. They would have to significantly clean up that water to use it,” said Lee Hefty, head of Miami-Dade’s division of environmental resource management.
However, wastewater injected into the boulder zone does not have to be as clean. And that’s the key to Miami-Dade’s plan to meet its responsibility to the federal government. The county already has 26 deep injection wells to shoot its wastewater into the boulder zone, but it still needs to build 14 more by 2025 to meet its deadline, according to Marisela Aranguiz, deputy director of Miami-Dade’s water and sewer department.
FPL and Miami-Dade seem confident that the injection wells will be approved since they’ve already begun work on other parts of the plan.
Along with the new injection wells, FPL would build an 8-mile pipeline to move treated wastewater from the county’s south district water treatment plant to Turkey Point. FPL and Miami-Dade are building a new water treatment plant at Turkey
Point to treat the water a second time before its used on the natural gas unit.
The plant is designed to treat up to 60 million gallons of wastewater a day, producing 45 million gallons of water suitable to use for cooling down the power plant. In addition to the 15 million gallons a day of treated wastewater used for the natural gas unit, the plant will have the capacity to produce another 30 million gallons of wastewater for the cooling canals, which would sharply decrease the amount of aquifer water used by FPL.
Construction on the new wastewater plant, approved by Miami-Dade’s commission in the summer of 2020, is expected to begin in late 2022 and be completed by 2024. Miami-Dade taxpayers are on the hook for $182 million of the total cost, and FPL ratepayers are funding the additional $300 million-plus in construction costs.
There’s no timeline for when DEP will rule on the injection well permits, which would each pump up to 18 million gallons a day into the boulder zone. Public comment ended Tuesday night, and the next step is for the state to respond with a yes or no.
FPL already has one deep injection well at Turkey Point. They use it to suck up super salty water from the underground plume and shoot it into the boulder zone.
As the final public comment meeting for the well permit, Danielle Hall, a manager in environmental services for FPL, said the new injection wells and wastewater agreement would result in FPL drawing less water from the Floridan aquifer.
If DEP approves the plan, it would be FPL’s first concrete shift away from its cooling canals, a win for environmentalists that have been complaining (and suing) the utility over them for years.
“It’s the lesser of evils,” said Laura Reynolds, an environmental consultant and board member of Friends of Biscayne Bay.
“Miami-Dade County has a lot of wastewater. We need to use a certain amount of it so that we’re being more efficient. FPL is the natural user of this. This is a good thing.”
Reynolds said advocates for cleaner water in Biscayne Bay would like to see FPL use more injection wells or technologies like mechanical draft towers for its remaining nuclear power units, rather than continuing to use the leaky canals. Turkey Point is the only nuclear power plant in the world that uses cooling canals.
And those canals are basically at sea level. With about one foot of sea rise, which is expected by 2030, they could be completely swamped.
“They should be replacing technology with something that works. This is a failed experiment,” she said.
FPL CLEANUP STATUS
As of a November status report, FPL said it had reduced the saltwater plume 42% from the 2018 level — about 18 billion gallons of super-salty water and 7 billion pounds of salt. It also found that the plume has stopped moving west toward Miami-Dade’s well fields, where it could have threatened South Florida’s drinking water.
Aranguiz, from MiamiDade’s water and sewer department, said, “there is no concern that MiamiDade’s western drinking wells will be impacted by FPL.”
The utility’s computer model shows that at this rate, it will not completely remove the saltwater plume from the aquifer by the year 10 deadline. The lower third of the aquifer will still have some super salty water, potentially from natural sources, FPL said.
“At this point, it is not clear whether the incomplete retraction is a result of a physical phenomenon or inaccuracies in the model,” the report read.
FPL didn’t suggest any changes to its strategy other than maybe tweaking the way it models the saltwater in the aquifer.
Hefty, from DERM, said he’s encouraged by the progress FPL has made in its $200 million cleanup.
“Saltwater intrusion is a complex issue. While we think Turkey Point is a component of it, it’s not the only component,” he said. “So far the evidence indicates that they’re compliant with our consent agreement and the evidence so far is indicating that we’re seeing improvements in the aquifer.”
Alex Harris: 305-376-5005, @harrisalexc