MIAMI-DADE COUNTY, Fla. – As nuclear power plants age, can they withstand the effects of climate change?
Last week, we looked at the resiliency questions being posed to FPL about its Turkey Point nuclear power plant.
This week we examine a more pressing problem, one that still hasn’t been fixed and that won’t meet a critical deadline.
Far beneath the surface of the Turkey Point nuclear power plant in south Miami-Dade County, undetected for decades, a giant plume of super salty water has been seeping into the Biscayne Aquifer, the source of our drinking water.
Miami Waterkeeper’s Rachel Silverstein has been closely monitoring the development of the plume emanating from the plant’s cooling canal system, an intricate grid of 32 canals dug out in 1973 to circulate water used to cool the plants two nuclear reactors. It’s the only cooling canal system like it in the world, created after scientists discovered the plant was polluting Biscayne Bay.
“It is going down about 80 feet,” she said. “It’s hitting what’s called the confining layer, and it is spreading out in every direction.”
In the early 1970s when the plant was first commissioned, the bay water that was being used to cool the reactors was being circulated back into the bay, and what scientists soon realized is that hot water was wreaking havoc on this fragile ecosystem, impacting marine life and killing sea grass.
So the DOJ then ordered FPL to create a closed-loop cooling system that wouldn’t pollute anything outside the property.
That seemed to work, until it didn’t. The canals are not lined and in 2011, South Florida Water Management determined that a hypersaline plume had been discharging from the cooling canals, moving westward past the plant’s boundaries and impacting the surrounding groundwater.
“The water from the cooling canal system has been heated, and all of the salt and other contamination, radioactive isotopes in the water gets very dense,” said Silverstein. “That dense water sinks into the holes in the rock that it’s sitting on top of, and into the groundwater below.”
That groundwater is the Biscayne Aquifer, and though the super salty plume has not yet reached the part of the aquifer that currently supplies water to Miami-Dade’s three million residents, for years it’s been spreading for miles.
“And it has, at times, been clocked moving at a rate of over a foot a day toward the drinking water well,” she said. “Heading for the Florida Keys and a small Miami-Dade County well head that’s located nearby and into Biscayne Bay.”
The subject of several lawsuits, the state and the county ultimately gave FPL 10 years to fix the problem and retract the plume by putting in extraction wells.
“So they basically put giant straws into the ground to suck the plume out of the ground and pull the plume back to the property line of the plant,” said Silverstein.
FPL recently admitted that it will not make the 10-year deadline to clean up the plume, but in a statement to Local 10 News, the utility company said its making progress and that the hydraulic well system it installed has stopped the plume from spreading.
“Over a six-year period, the well system has removed more than 36 billion gallons of hypersaline groundwater, which is a significant reduction,” said Bill Orlove, an FPL spokesperson. His full statement can be read at the bottom of this story.
But the county says it’s not enough, and that the plume is still impacting the deeper parts of the aquifer.
“It’s why we’ve asked FPL to go back to the drawing board and come up with a better plan to better retract the entirety of the plume, even at the deeper levels of the aquifer,” said Miami-Dade County Chief Resiliency Officer Loren Parra.
Neither the county nor FPL have given an estimated timeline for when they anticipate the whole plume to be retracted, and that, says Silverstein, is worrisome.
“We’re waiting to see what the county is going to do and require them to adjust the plan in order to meet targets,” she said. “What’s going to happen next? We are all in South Florida connected to the fate of Turkey Point and if Turkey Point is safe and resilient, then we can be safe and resilient. And if Turkey Point is not safe and resilient, then we will not be either.”
On the strength of the remediation plan FPL has with the county, FPL has been able to negotiate new Clean Water Act permits from the state of Florida and, as we mentioned last week, a license extension from the NRC to keep the plant operating till the year 2052.
Miami Waterkeeper is challenging that extension.
Here is the statement by Bill Orlove, a spokesperson for FPL:
Turkey Point has operated safely and reliably for decades, providing low-cost, emissions-free energy to Florida Power & Light customers. The Nuclear Regulatory Commission, as well as other regulatory agencies, confirm the facility’s safe operations and approve Turkey Point’s continued operations into the 2050s.
Status of the cooling canals
Turkey Point Nuclear Power Plant has been using a 168-linear-mile, closed-loop canal system that recycles non-potable groundwater as part of the power generation process since 1973. Occasionally, in years that are drier than normal, evaporation could exceed rainfall. In those instances, salinity levels in the cooling canals increased to levels greater than seawater, and this denser water pushed out the naturally occurring saline groundwater along the bottom of the aquifer, eventually spreading past the boundaries of the cooling canals.
Working collaboratively with Miami-Dade County, the South Florida Water Management District and the Florida Department of Environmental Protection, FPL received approval for a remediation project that:
- Prevents hypersaline water from beneath the cooling canals from migrating north and west.
- Removes existing hypersaline groundwater.
The agencies also authorized FPL to use brackish groundwater 1,000 feet below the Biscayne aquifer to:
- Replace evaporated water that exceeds rainfall.
- Eliminate the cooling canals as a source of hypersaline groundwater.
FPL is committed to effectively managing the canals’ water:
- The company’s strategic use of brackish water to manage salinity levels has resulted in the lowest annual average salinity levels since 1973.
- The water has essentially returned to the same salinity as seawater.
- A recovery well system installed by the company creates a hydraulic barrier that prevents groundwater from beneath the site from spreading.
- Over a six-year period, the well system has removed more than 36 billion gallons of hypersaline groundwater, which is a significant reduction.
In 2022, a Florida administrative judge supported the Florida Department of Environmental Protection’s renewal of the permit to operate the plant’s cooling canal system. The ruling found that data and expert testimony demonstrates operations of the facility and the cooling canal system meet all federal and state environmental regulations.
In addition to safety, environmental stewardship serves as a foundation for the company’s development, construction and operation of all its facilities. An example specific to Turkey Point includes the crocodile monitoring program. On the brink of extirpation from the U.S. in the late 1970s due to habitat loss, the American crocodile has made a dramatic comeback in the habitat surrounding the plant. In the 1980s, FPL initiated the crocodile monitoring program at the plant. The cooling canal system offers ideal nesting conditions for the American crocodile. Our crocodile monitoring program includes protecting these nesting areas, completing population surveys and regulating plant activity at night and during nesting season. Since 1978, FPL biologists have tagged 10,000 hatchlings at Turkey Point. Last year, the canals yielded the third highest number of American crocodile hatchlings (529) in the plant’s history. With the help of FPL’s conservation efforts, the American crocodile was downlisted from an endangered species to a threatened species in 2007.
Operating safely in severe weather conditions
Safety is the cornerstone of our nuclear operations. All our nuclear plants are designed to withstand earthquakes, hurricanes and other natural events stronger than ever recorded in their respective regions. Site design at all our nuclear sites provides extra protection against flooding and extreme storm surge, including all sites being elevated at least 20 feet above sea level, which is higher than many buildings in nearby areas. In collaboration with the nuclear industry, the company created regional response centers that include pre-built equipment, located away from nuclear sites, that can be brought into any of our nuclear plants in response to a natural disaster at a site. We have made significant upgrades to our nuclear facilities, including:
- High-capacity pumps to provide additional backup cooling water for safety systems.
- Pre-staged additional backup equipment in onsite reinforced buildings.
- Confirmed the ability of our plants to withstand extreme natural events, such as hurricanes, earthquakes, flooding and fires.
- Turkey Point took a direct hit from one of the strongest hurricanes in history, Category 5 Hurricane Andrew, in 1992. The facility’s critical infrastructure was not damaged.
- Our plant operators can shut down the plant within a matter of seconds, if necessary.
- For one full week every six weeks, plant operators are in training that includes the use of a simulator to demonstrate their ability to safely operate the plant in a variety of worst-case scenarios that include earthquakes, severe storms and flooding, and loss of power, among other situations.
In 2013, FPL submitted an in-depth independent study to the NRC clearly demonstrating that the plant can withstand severe flooding associated with the most extreme natural events, including a storm surge higher than that produced by Category 5 Hurricane Andrew. The updated study considered the impact of a tsunami (no matter how unlikely in Florida), the maximum possible rainfall in the area and projected sea-level rise. We have extensively analyzed data from NOAA and other agencies, and there is adequate protection to safely and reliably operate the facility, along with the cooling canals, for the lifespan of Turkey Point’s operating units, through the 2050s.
Critical plant systems are further protected by additional flood barriers, and the NRC has required that each nuclear site in the U.S. validate its storm surge protection. FPL responded quickly to meet these requirements. It’s also important to note that the cooling canal system at Turkey Point is protected by an 8-foot-high berm.
The reactors and other nuclear components are protected inside a three-foot thick, steel-reinforced concrete building that is fully sealed. Safety systems such as the emergency diesel generators, as well as additional generators and pumps, are elevated an additional two feet above base elevation and enclosed in steel-reinforced concrete buildings that are several feet thick. In addition, Turkey Point has access to additional off-site emergency generators within 24 hours.
Last September, the NRC approved the subsequent license renewal for Turkey Point after the company completed a rigorous reapplication process, providing additional documents for a site-specific environmental impact statement that led to restoring the initial subsequent license approval in 2019.