This will be a multi-part post aimed at addressing a convoluted and emotional issue. It will attempt to satisfactorily answer the following questions.
- Why are organizations targeting the Turkey Point power station?
- Why do they claim that the plant is threatening the Everglades National Park, the Biscayne Bay National Park and the groundwater adjacent to the facility?
- What are the documented concerns and what impact do they have?
- Do the tritium measurements that have been reported in various news media really indicate that Turkey Point Units 3 & 4 (the nuclear units at the 5-unit power station) are “leaking?”
This is a story with a very personal aspect. Many of you have heard me tell the story of the time nearly 50 years ago when my father came home from work and told me about the new power plant that his company was building that did not even need smokestacks. Turkey Point was the unnamed power plant in that story; its construction began in 1967, the year I celebrated my 8th birthday.
That was the beginning of my appreciation of the advantages that nuclear fission has over its hydrocarbon competition.
I also have a life long fondness for Florida Power & Light (FP&L). The company and its employees were topics of many family discussions while I was growing up; in fact, Mom occasionally expressed some minor annoyance at Dad for bringing his work home so often. A fair portion of the adults that played a role in my life while growing up proudly worked in various roles at the company. I eagerly looked forward to the annual company Christmas party and the annual company picnics held on the site of the Cutler Plant.
The big banyan trees were great fun for climbing and swinging on the roots.
I fondly remember the Tuesday each month when my white collar, long distance-commuting Dad was able to linger with us at breakfast in his more casual “storm training” attire. Unlike the Miami office where he worked the other 19 days of the month, storm training was held in much closer and accessible Ft. Lauderdale; he didn’t need to allow 45-60 minutes for the traffic.
On storm training days, Dad made sure that his hardhat was in the car before he left for the monthly practical exercises in power system restoration, which is an “all hands on deck” effort for a power company. I’ve lived in places where the power was knocked out by storms and remember at least three separate instances where the whole neighborhood gathered on the street and cheered the power company employees who turned the lights back on. Sometimes the crews were from companies located several states away.
Living in the home of a good man devoted to his service-oriented profession helped inspire me choose a career in the service of others.
To this day, FP&L is a positive influence on my family; Mom is one of those famous “widows” — as in “this stock is suitable for widows and orphans” — that receives reliable dividend checks from FP&L. She also receives the survivor’s portion of the pension Dad earned during his 35 years of employment with the company. There are hundreds of thousands of people who can share similar personal stories about positive family associations with FP&L.
There are tens of millions of Florida residents and tourists that have benefitted from FP&L’s 90 years of service as a rate-regulated electric utility with an obligation to provide power to all customers at the highest possible level of reliability within cost constraints determined by the public utility commission.
All of that information is my way of disclosing that I instinctively distrust people that demonize “the power company.” I’m offended when out-of-state special interest groups like the deceptively-named1 “Southern Alliance for Clean Energy” attack an admirable company that has achieved a long record of service and stewardship.
If you’re looking for balanced reporting, you might want to stop reading now. If you want informed answers to the questions I listed at the beginning of the article from someone who is not a company spokesperson or an employee but is also not an anti-corporate hater with an agenda, I hope to make this worth your time.
Turkey Point is under attack
I started hearing about recent efforts to publicize what opponents have characterized as “leaks of radioactive elements and other pollutants into Florida surface and ground water” a couple of weeks ago. I was energized into action after finding a March 22 New York Times story titled Nuclear Plant Leak Threatens Drinking Water Wells in Florida.
Though the headline — obviously designed to attract attention — claimed that the nuclear plants were “threatening” groundwater, the story clearly stated that tritium “was found in doses far too low to harm people” and later quoted a company spokesperson.
He [Robert L. Gould] emphasized that the trace levels of tritium were far below the danger levels set by the Environmental Protection Agency for drinking water. The company has been in contact with the federal agency, he said.
None of these problems, Mr. Gould said, are threatening the state’s drinking water supply or even the bay’s health. The problem is mostly in areas right near the plant, he added. The closest the saltwater plume is to the water wells is about four miles away. “I really need to stress that there is no safety risk: There is no risk to the bay or to the drinking water,” Mr. Gould said. “The way it’s been portrayed by some is simply unfair. It’s extremely misleading.”
Before providing what should be calming information, here’s how the New York Times story sought to capture readers that were initially attracted by the sensational headline.
When Florida’s largest power company added two nuclear reactors to an existing plant that sat between two national parks — Biscayne Bay and the Everglades — the decision raised the concerns of environmentalists and some government officials about the possible effects on water quality and marine life.
Now more than four decades later, Florida Power & Light’s reactors at Turkey Point, built to satisfy the power needs of a booming Miami, are facing their greatest crisis. A recent study commissioned by the county concluded that Turkey Point’s old cooling canal system was leaking polluted water into Biscayne Bay.
There are several problems with that statement.
Problem 1: The Turkey Point power station existed long before Biscayne National Park, which was formally established in 1980. It existed before 1968 when the area first gained some development protection when it was designated by Congress and President Johnson as a National Monument. At the time that the power station was built, the area was a prime development target for a project known as the city of Islandia.
FP&L’s 1964 decision to purchase land and build a power plant at Turkey Point is one of the prime reasons that the area was protected from intensive development. McGregor Smith, the chairman of the board of FP&L was committed to preserving as much of the waterways and land surrounding the plant as possible.
Found on Newspapers.com
He envisioned the area as a multi-use area that would include a wildlife refuge, a Boy Scout and Girl Scout camping area, a marine research laboratory, picnic areas and beaches. Smith’s visions were largely achieved. Much of what the company preserved from development was later incorporated into the Biscayne National Park. The park is a place that has received numerous accolades over the years lauding its environmental and recreational value. Park Vision has a nicely illustrated story about the park.
One positive, but unintended effect of the Turkey Point plant and its cooling canal system (CCS) is that endangered crocodiles were attracted to the warm salty waters as a good place to lay eggs and incubate them to hatchlings. The crocodile’s decision to begin using Turkey Point’s CCS as an incubator, along with the protection afforded the reptiles by FP&L biologists and security personnel has been credited by conservationists with helping the crocodile population increase enough to move it off of the endangered species list to a status of “threatened.”
Problem 2: The easternmost boundary of Everglades National Park is about six miles west of the CCS for the Turkey Point Power station, on the other side of US 1. That’s a pretty substantial buffer area.
Problem 3: The referenced study did not prove that the plant was leaking polluted water into Biscayne Bay.
Analysis of study being used as basis for recent attacks
Dr. David Chin, a civil engineering professor at the University of Miami, was commissioned by Miami-Dade County to perform a study and produce a deliverable within a 120 day time frame. He documents the limitations of the study and what it was unable to determine. His commissioned study does not list any other authors and does not display the obvious signs of having been peer reviewed.
Chin’s document includes measurements indicating that there are deep pockets of water adjacent to the CCS that exhibited higher than expected concentrations of certain chemicals or elements.
Dr. Chin hypothesized that the isotopes and compounds migrated from the cooling canals into the dredged deep spots and from there into the adjacent aquifer and bay waters. Those deep areas are identified by dark blue circles on the map below.
Chin asserts that the boundary of the hypersaline that has percolated from the cooling canals is defined by a tritium concentration of 20 pCi/liter. He states that level is sufficiently elevated from the natural level to be a good marker. His chosen marker is 1/1000th of the 20,000 pCi/liter EPA says is safe for safe drinking water.
Aside: Here is the basis for the EPA limit. If a person drank nothing but water containing that level of tritium, her dose from tritium would be 0.04 mSv/year.
According to the Health Physics Society position paper titled Radiation Risk in Perspective, no discernable health effects occur for doses below 50 – 100 mSv. End Aside.
This is Dr. Chin’s explanation for his selection of 20 pCi/liter as the boundary. Note: A picocurie (pCi) is 10e-12 curies. That is one millionth of a millionth curies. A picocurie is even smaller than the incredibly tiny SI unit of a bequerel (defined as one decay per second). It takes 27 picocuries to equal one bequerel.
Natural groundwater at the base of the Biscayne Aquifer would be expected to have relatively low concentrations of tritium. A threshold concentration of 20 pCi/L has been used as a baseline to infer the presence of groundwater originating from the CCS. Groundwater with concentrations below 20 pCi/L are presumed not to be affected by the CCS. FPL does not concur with the selection of 20 pCi/L as a threshold or background tritium concentration for surface water, pore water, or shallow groundwater.
The basis of FPL’s contention regarding the 20 pCi/L threshold is that multiple factors such as atmospheric deposition, vapor exchange, and errors in laboratory analysis can influence reported tritium levels. The FPL assertion is reasonable and is supported by measured data that indicate atmospheric and vapor exchange effects on tritium concentrations can be particularly significant in surface water and shallow groundwater, with significance decreasing with distance from the CCS. However, at depth, the CCS appears to be the primary source of tritium, and using tritium as a tracer in the lower elevations of the Biscayne Aquifer is reasonable.
Reported measurements show groundwater tritium concentrations in excess of 3000 pCi/L near the CCS, with concentrations decreasing with distance from the CCS, and found at concentrations of hundreds of pCi/L three miles west of the CCS at depth. The approximate limit of the 20 pCi/L concentration contour is 3.8 – 4.7 mi west of the CCS and 2.1 mi east of the CCS. Based on the strength of these data and supporting analyses, it is reasonable to conclude that operation of the CCS has impacted the salinity of the Biscayne Aquifer within the limits of the 20 pCi/L contour.
(Source: Chin, David A. The Cooling-Canal System at the FPL Turkey Point Power Station Pg 12-13)
I question Dr. Chin’s logic. He does not explain why he says “at depth, the CCS appears to be the primary source of tritium…”
FP&L’s reactors, like all other water cooled reactors, produce some tritium. That low activity hydrogen isotope is inseparable from water. The company is permitted to discharge tritiated water into the cooling canal system, which is separated from the surrounding waters and aquifers by soil boundaries. Tritium concentration in the cooling canals range from about 1200 pCi/liter to about 15,000 pCi/liter at certain peak times.
There is no cover on the canal system; tritiated water in the canal water will evaporate along with all other water. Especially on cool days during dry spells, when the cooling canal temperature is roughly 100 ℉, there is vapor above the body of water. Any breezes coming off of the Bay and blowing across the CCS will move tritiated vapor inland. Winds in the opposite direction move tritiated vapor towards the Bay.
It will precipitate out and sink into the aquifer like any other water. The tritium concentration falls as distance from the source increases.
The people attacking the plant point out that the cooling canal system is not lined, but that is the way that the system was designed and approved. It is a permitted industrial waste water facility. It’s worth contemplating the environmental consequences of building and maintaining a lined canal system that covers 9 square miles of swampland lined with mangrove forests. It’s also important to note that the water depth in the CCS is less than 4 feet, with an average of less than 3 feet.
Since FP&L is a rate regulated monopoly utility, it would be allowed to include any costs associated with building a lined system in its rate base and it would be allowed to receive a modest rate of return on that investment. Despite what some opponents say, FP&L’s decision to build the canals as they are was not driven by corporate greed.
Salt Water Intrusion
Even after defining the plume boundary as just 20 pCi/liter, Dr. Chin concluded that the hypersalinity water — which he blames on seepage from the CCS — was still several miles seaward of the closest drinking water wells. Historical documents indicate that saltwater intrusion was measured at about the same location (5 miles inland from the Biscayne Bay) before the Turkey Point power station was ever built.
As a reasonably aware middle and high school student in South Florida, I have a clear memory of studying salt water intrusion issues and learning that the effect is often exacerbated by pumping too much water out of aquifers. Excessive withdrawal reduces the pressure (head) that generally keeps salt water out and allows it to invade the fresh water deposits. The problem is worsened by droughts, thirsty green lawns, green golf courses, limestone quarries and the impervious development roads, parking lots and shopping centers associated with suburbia.
Here is what Dr. Chin wrote about sea water intrusion.
The landward extent of the saltwater interface (i.e., the 1000 mg/L isochlor) varies naturally in response to a variety of factors, such as seasonal variations groundwater recharge and variations in rates at which groundwater is pumped from the aquifer. For example, prolonged droughts or excessive water usage inland that reduce water-table elevations can cause increased salinity intrusion. Prior to the construction of the CCS, the groundwater underlying the Turkey Point site was naturally saline due to the proximity of the site to the coast. In fact, had the groundwater not been saline, construction of the cooling-canal system at Turkey Point would not have been permitted.
It has always been recognized that construction of the CCS without any mitigating salinity-control systems would cause the saltwater interface to move further inland.
Dr. Chin’s study hypothesizes that small variations in levels in the cooling canal, along with changes in density due to variations in salinity from the balance between rainfall and evaporation plays a large role in pushing water out of the canals and through the porous limestone characteristic of the South Florida subsurface. He does not mention the impact of withdrawal rates in helping saltwater plumes to move, if that is what is actually happening.
Dr. Chin also makes a few guesses about the source of recent temperature, salinity and algae challenges in the cooling canals that are demonstrably false. For example, he calculates that the heat rejection rate from the power plants into the cooling canals experienced a step increase from 2800 MW to 5500 MW.
He attributes that jump to a power upgrade on units 3 & 4. That uprate changed the licensed thermal power generation from each plant from 2300 MWth to 2644 MWth. During the time that elapsed between the two measured total heat rejection rates, FP&L shut down a 450 MWe oil/natural gas steam plant that also used the CCS as its heat sink. Since that time, it has shut down the other fossil unit using the CCS.
In a future article, I’ll provide more details about the actual heat balances. With the information already provided, it should be reasonably obvious that Dr. Chin’s model was giving incorrect information.
One of the major problems I have with Dr. Chin’s study is that it only includes the word “drought” once, and that was just in a paragraph describing hypothetical effects. He is apparently unaware that the measured rainfall into the canal cooling system in 2012 and 2013 averaged 20″ per year when the normal average is 75″. As of September 2014, only 26″ of rain had fallen into the canal system.
To be continued.
1 “Southern Alliance for Clean Energy is a not-for-profit, non-partisan organization working to promote responsible energy choices that solve climate change problems and ensure clean, safe and healthy communities throughout the Southeast.” (IRS Form 990, SACE 2014) What that description fails to mention is that SACE actively campaigns against nuclear energy.