|
Anastasia Human Factor III: The Impact of a Boiling Water Nuclear Reactor
|
Continued...
|
| |
|
Discussion
I concluded that the nuclear power plant affects the water quality and microbial communities in the plant's intake and discharge creeks. While there might have been some natural environmental variations between the two creeks if they had been left in their natural state, today that is no longer the case. There are differences in the three creeks that can reasonably be attributed to the nuclear reactor. One striking example of the nuclear reactor's effect on Forked River and Oyster Creek is the change in those creeks' velocities compared to Cedar Creek. This is explained by the sheer amount of water being pulled through the creeks by the reactor. Also, the flow of Forked River is reversed, which is explained by the force of the reactor sucking water in from Barnegat Bay. The increase in velocity explains the higher turbidity in Forked River and Oyster Creek compared to Cedar Creek; the faster water is picking up and carrying more sediment. Also, Oyster Creek has a higher turbidity than Forked River, which is explained by the force with which the water discharged from the reactor is stirring up sediment. The EcoPlate™ data showed differences in the microbial communities in Forked River compared to Cedar Creek. The explanation for this is that Forked River has been turned into an arm of the bay, while Cedar Creek remains in its natural state. The pH in both Oyster Creek and Forked River is 0.4 higher than the pH in Cedar Creek. The explanation for this is that water is drawn by the plant through Forked River and then released into Oyster Creek. It is water from the Barnegat Bay, and the bay's pH almost exactly matches that of Forked River and Oyster Creek (Roda, 2004). The plant's discharge of hot water into Oyster Creek explains the 6°C. higher temperature difference between Oyster Creek and Cedar Creek and the 5°C. higher temperature between Oyster Creek and Forked River. No apparent natural cause accounts for these dramatic temperature differences between Oyster Creek and the other two creeks. The temperature differences also likely affect other indicators in Oyster Creek. The higher temperature in Oyster Creek would explain the higher average numbers of bacteria in Oyster Creek compared to Cedar Creek and Forked River. Higher temperatures would especially affect the number of human-pathogen-indicator bacteria, because pathogens survive best at the human body temperature of 37°C. The higher temperature caused by the plant also explains the colony count data within Oyster Creek. On both agars, bacteria numbers at the head of Oyster Creek were extremely small, with the lowest average colony counts of any site studied. By contrast, the petri dishes plated with water from the other two Oyster Creek sites had by far the highest average of any site studied; they were consistently covered with one type of bacterium seen at no other site, and they showed few if any colonies of any other kind. An explanation is that most bacteria are killed in the reactor by the intense heat, which explains the low colony counts at the head of the creek. By the time the water gets to the middle of the creek, however, the cooling of the water has created an ideal environment for this one type of bacterium, whose population explodes and continues to increase throughout the rest of the creek.   
Bacteria Colony Counts: MacConkey's Agar (top) and Nutrient Agar (Click to view)
|
Perhaps the most important differences found in this project are those between Oyster Creek and Forked River. These two creeks would have been much more similar if they were unaffected by outside forces. They are close together, flow through almost identical environments, have sources close to each other, are almost the same length and width, and if human presence is considered, have the same kind and amount of development along their lengths. However, they have become very different. They are also more different from each other than either one is from the control creek. The only explanation is the operation of the Oyster Creek nuclear reactor. Key differences include the higher temperature, turbidity, and velocity of the water in Oyster Creek, and the difference in the number and type of bacteria in the creeks.
The reactor increases the variability of water-quality indicators and number of bacteria colonies in Oyster Creek and Forked River, compared to the variations within Cedar Creek. The reactor's operation explains why EcoPlate™ data show fewer differences between Forked River and Oyster Creek than in Cedar Creek. The reactor has reduced the microbial diversity in the creeks. The agar study results for Oyster Creek support this observation. There is one dominant and highly populous kind of bacteria in the middle and at the mouths of the creek, and almost no other kind of bacteria. My overall hypothesis that the Oyster Creek reactor has affected the water in its intake and discharge creeks was accepted. My hypothesis that the reactor affects the water quality in the creeks was accepted. My hypothesis that the microbial communities in the intake and discharge creeks would be different from a control creek was accepted. My hypothesis that there would be fewer bacteria in the discharge creek was rejected; there were almost no bacteria at the head of that creek, but far more in the middle and at its mouth than at any other site studied. The study strongly suggests that the reactor's release of heated water into the discharge creek has altered the water parameters and the microbial community in that creek. This alteration could be prevented if the water were cooled to its natural temperature before being discharged. Technology is available to perform residual heat removal (RHR) and is being used in more modern reactors. Oyster Creek has applied for a 20-year license extension. There are 34 boiling water reactors similar to Oyster Creek operating in the United States and 60 more worldwide, mostly in Japan and Sweden (Information and Issues, 2005). Many of the reactors operating in the United States will apply for license operating extensions within the next decade. As a condition of license renewal, the companies that own and operate these reactors could be required to install systems to cool the water before discharge, which would substantially avoid altering the ecosystems in the discharge creeks of these reactors. Conclusions  The Oyster Creek power plant 2. The reactor has no effect on dissolved oxygen, ammonia-nitrogen, or nitrate-nitrogen. 3. The microbial communities are different in the intake and discharge creeks. 4. There are almost no bacteria at the head of Oyster Creek but far more in the middle and at its mouth than at any other site studied. 5. There is one bacterium in the middle and at the mouth of Oyster Creek that appears in small translucent colonies and grows prolifically on MacConkey's agar. I had not observed this morphotype before in any other site, in any of the multiple bacteria studies I have conducted in the estuary. |
