Three Mile Island Accident Study

Countless nuclear power plant accidents have been occurring quite frequently since its invention. Some accidents have even been underestimated,

realize that the plant was having an accident with the coolant level. The tubes holding the nuclear fuel began to melt since they became over heated which also caused fuel pellets to melt. Even though this was the most dangerous kind of nuclear accident, the radiation did not reach outside of the containment building nor did it release out into the environment. There were no immediate injuries or deaths reported from the raditation to the faculty workers.

This did not mean that the valve had actually performed that action, but rather that the message was received by the valve (History Channel…). The light shut off, which indicated to the operators that the valve had been opened and reclosed, however the valve did not reclose (Wikipedia). The PORV remained open and was releasing a combination of coolant and radioactive material. As coolant water was released, no instrument indicated this to the operators; the operators had only been trained to estimate the amount of water in the reactor by doing calculations based upon pressure readings. These pressure readings were now skewed and thus the calculations were wrong and based upon these wrong calculations, the operators stopped the flow of cooling water to the reactor. The lack of water caused overheating within the reactor and according to the US Nuclear Regulatory Commission’s findings, about half of the reactor’s core melted. Operators had no way of knowing this and also were not trained to handle such an event. Unlike the event at Chernobyl, the reactor stayed intact and massive amounts of radiation were not leaked into the surrounding area. This containment, led nuclear engineer, Jack Herbein to announce publically that the citizens of Harrisburg were in no danger. Herbein’s comments on the plant were near fraudulent because no one was certain as to the actual danger that they were in

The operator opened the relief valve to release the pressure in which is in the reactor, while the pressure inside the reactor was decreasing up to the required level due to the improper respond and malfunctioning lead to failure of the valve to close. Not only wrong readings by the engineers, but also an inputting excess amount of computer data lead to the technical failure, the slag in the ongoing analyzing process and immediately human alert was alarmed in the power plant. But this issue as not stopped yet, the core of the reactor was beginning to cook. The incident China syndrome was named since there was the increasing of temperature from 4300 degrees Celsius to 5300degree at which meltdown. Hazardous radioactive gas was exposed all over the plant because of the leaked water from the open valve in an adjacent building. No emergency precaution was taken when the second accident of radioactive gas took place. In the video, there was also a communication error to note down and transfer the report were the problems facing the operators to take the decision quickly. Also, one of the employers found the fault in the explosion theory of co-worker prediction the hydrogen bubble was never a threat, it was a human error. Finally, it was the most devastating incident that was spread in the news all over the world and local people

The Three Mile Island TMI-2 incident had a large impact on world history. It showed America their first glimpse of what can happen with nuclear power, it foreshadowed the Chernobyl incident eight years later, it decreased public opinion of nuclear power, and it increased safety standards for nuclear reactors across the world. Three Mile Island is a nuclear power plant in Southeastern Pennsylvania with two nuclear fission reactors. On March 28, 1979, reactor two suffered a partial core meltdown that caused a widespread radiation scare. Although negligible amounts of radiation actually escaped into the atmosphere, nearby towns were left deserted for a couple days until the media finally got the story straight and the government released an official

Carl Michelson, a science-fiction writer with adept expertise in nuclear engineering and a respected advisor in the world of nuclear reactors also brings to attention a fault in the Babcock and Wilcox pressurizer. He notes that a U-shaped pipe between the pressurizer and coolant loop could prevent water from flowing, thus filling the pressurizer beyond a safe limit while draining the reactor. Yet again, this warning was halted by the choking grip of bureaucratic

On the 11th of March, 2011, a 9.0-magnitude earthquake struck near the eastern coast of Japan. Emergency shutdown procedures went into effect when the earthquake was spotted, but this was not the main cause of the destruction of the nuclear reactor. The first line of defense was to immediately stop the nuclear fission within the reactor by inserting neutron absorbing rods to stop the reaction. After the engineers successfully stopped the nuclear fission reaction, immense heat and pressure was still prominent and needed to be relieved as soon as possible. Fresh water was brought in and dumped onto the rods but a tsunami inevitably followed as soon as the earthquake was felt as the source of the natural disaster was on the ocean floor. The tidal wave severely damaged the power supply system that was meant to maintain the flow was cold water. On March 12, 2011, diesel powered generators were initiated in an attempt to alleviate the failure of the generators that were powering the entire plant. Unfortunately, the diesel powered generator was insufficient enough to cool the large reactor as the heat building up within was accumulating in large amounts; more than what nuclear engineers originally presumed. Water continued to evaporate causing a hydrogen gas to form when the fuel rods underwent a chemical reaction with the steam. Hydrogen gas is an important element to take into consideration as too much of this element can cause an explosion within the reactor. Workers quickly

An author from Engineering.com named, The Engineer wrote a fairly descriptive article on the events that took place at Three Mile Island in October of 2006. The Three Mile Island incident occurred on March 27, 1979. Two men were cleaning a clog in an ion-exchange tank using compressed air from a general-purpose air system. There was a water line and another compressed air system that controlled valves in the plant. The Engineer (2006), points out that the 3 systems have similar fittings and a hose was connected between the instrument air system and the water line. This led to a loss of feed water to the steam generators and no way to cool down the reactor. With no way to be cooled, the system

Figure 1 shows normal operation of a reactor along with the meltdown process to put in to perspective the summary of Fukushima Daiichi disaster events. In Short it does something like this: The Tohoku earthquake, March 11 2011, triggered a tsunami both of which caused damage to the 4 power plants at Fukushima. The damage caused equipment failures and a loss-of coolant accident due to the in ability to supply the reactors with cooling

After the dramatic power surge occurred, and the ensuing steam and hydrogen explosion that destroyed the reactor core and killed several workers, there was a second explosion. This caused the graphite moderator to burst into flames, which was the main cause of the release of radioactivity into the environment (Kubiszewski & Cleveland 2009). According to Freedom for Fussion Organization, the lack of a steel reinforcement concrete containment

The time schedule for the experimental operation suffered an unexpected delay. The Kiev power grid suffered a shortage of electricity in the grid. The control grid operator requested the Chernobyl facility to delay the operation in order to assist in the electricity demand of the peak hour. The Chernobyl director agreed to the request and officially postponed the operation until their energy output was no longer necessary. Despite the delay, the staff of reactor four proceeded in necessary preparation for experiment. The crew disabled non-energy affecting routines and the passive cooling system responsible for maintaining the reactor four's core; the system supplied emergency

This happened due to a flaw in the RBMK design (Smith and Beresford, 2005). In most reactors, a pending disaster would lead to the machine reducing its power, and avoiding this type of disaster (Smith and Beresford, 2005). However, in this design of reactor, when water or steam is lost, power levels rise, steam is created, and toxins can be released (Smith and Beresford, 2005). Thus, the radiation from this explosion was spread in the air.

Despite these modifications, the RBMK reactors continue to have problems. One site in particular, the Leningrad Nuclear Power Plant, has had multiple issues in the last few years. In 2013, the graphite moderator was operating improperly due to deformities and cracks in its graphite moderator core. These types of moderator failures have the potential to lead to larger problems, such as the ones identified after the Chernobyl incident. Therefore, the reactor was shut down for an 18-month period in order to repair the deformed moderator [12]. The 18-month project included research and experimentation with reactor operating and monitoring procedures, and will lead to the discovered solutions implementation on all existing RBMK reactors in the future. Despite this solution, the Leningrad RBMKs shut down again for multiple days in October 2015 due to a minor storm that blew seaweed into the reactor’s water supply intake [13]. The reactor faced no issues except for minor production delays and its automatic SCRAM procedures went off without issue; however, the fact that a minor natural occurrence caused a shutdown of the reactor raised eyebrows to the reactors’ true safety. It should be noted that water intake caused shutdowns have occurred internationally, yet they face specific scrutinization when involved with the RBMK reactors [13].

For 83 minutes, reactor number 4 exploded, sparking the first disaster of its kind in the history of mankind (Rybar). The blaze would last for ten days, making it essentially impossible for anyone to enter the plant in order to slow or stop the amount of radioactive materials the were leaking into the

On March 28, 1979, near Middletown, Pennsylvania, a Unit 2 (TMI-2) reactor partially melted down. The reactor released small amounts of radioactivity, but none of it had any detectable health effects on employees or workers at the plant. Then, from the years of 1980 to 1993, workers helped to clean up the accident. This accident created a need for better safety precautions and work operations. It changed emergency response planning, reactor operator training, human factors engineering, and radiation protection, which are only a few nuclear power plant operations that demanded to be fixed (“Backgrounder on the Three Mile Island accident”, 2014). As stated by Columbia Electronic Encyclopedia in the article “Three Mile Island” (2013), “The accident also increased public concern over the dangers of nuclear power and slowed construction of other reactors; no new reactors were approved for construction following the accident until 2012.” There were two nuclear reactors located at the plant, both owned by General Public Utilities, however only one of the two failed to work (Bowen, Robert M., 1983). This accident had a large impact on how stable mechanisms in nuclear situations need to be as well as how situations such as this one are handled.