A Catastrophic Nuclear accident, the Chernobyl disaster, a level 7 nuclear accident on the International Nuclear Event Scale (INES), occurred in the Number 4 light water graphite moderated reactor at theChernobyl Nuclear Power Plant nearPripyat, on 26 April 1986. At that time, this area belonged to theUkrainian Soviet Socialist Republic of theSoviet Union (USSR).

This horrific meltdown has rendered many regions of Ukraine dangerously radioactive, leading to rising cancer rates and straight deaths. The severity of the disaster was a strong blow for the Soviet Government and, since this incident, the global perceptions about nuclear power have changed drastically. The reason for the occurrence was many failures including faults in the reactor design, and poorly informed employees.

The major factors that led to the Chernobyl accident were the operation of the reactor at irregular intervals, violation of operating regulations and positive void coefficient characteristic of the reactor, which is a number used to get an estimate of the amount of reactivity of a nuclear reactor that changes along with the voids (typically steam bubbles) forming in the reactor moderator or coolant. In addition, perceptible lack of knowledge in the station staff regarding the characteristics and working of the reactor, substandard control rod design and inadequate monitoring were equally responsible. On the whole, it was the absence of the 'safety culture' that resulted in the disaster.

More than 30 people were killed at the place of the accident because of the radiation levels in the surrounding 20-mile radius, and nearly 1,35,000 people were evacuated. The consequences of this accident are being felt even today among which serious medical conditions such as cancer, breathing problems, skin diseases are just a few. Six people per million suffered from cancer before the accident had happened. But the statistics from 1986 - 1997 showed a rise to 45 cases per million.

As per the information in possession of the KGB of the USSR, design aberrations and violations of construction norms had occurred at various places in the structure. The pillars in the generator room were erected with a deviation of up to 100mm from the reference axis, and the horizontal connections were missing. Also, there was an

irregularity of up to 150 mm in the wall panels. Even the waterproofing was damaged in many places, and the Deputy Head of the Construction Directorate had ordered to backfill the foundation in those places. The damage could have led to groundwater seepage into the station, and consequently, radioactive contamination of the environment. The necessary attention was not paid to the foundation, and the cement plant operated erratically with a poor output. There were gaps during the laying of the foundation due to inconsistency while pouring cement.

The accident took place while performing an experiment. It was not under the normal

regime of operation, and no usual rules applied. Many safety procedures were also being violated as only 6 rods were in function whereas minimum 30 rods had to be used to control the fission of Uranium in the reactor. For the conduction of the test, the reactor should have had a power of 1000 MW but, because of operational error, the power dropped to 30 MW.

The engineers believed that they were fully aware of what was going on. 

Unfortunately, their judgement was utterly wrong! There was a lack of proper communication between the team in-charge and the personnel responsible for the operation of the nuclear reactor. The reactor became very unstable because of an increase in the coolant flow and a fall in the steam pressure following which, a sudden increase in temperature made the fuel explode as they completely lost control over the reactor.

The company was negligent towards its basic duty as no accurate and timely information on possible hazards to the people in the vicinity was provided although the public has a right to such information. People in the leading roles and the sub-staff were not technically trained, and the workers were not even given safety equipment. This holocaust was bound to happen! With there being such grave structural misapprehensions, it seems that the conditions were perfect.

For a nation as large as the then superpower, the USSR, the response to the disaster was not adequately handled, caused primarily due to a combination of a deficiency of foresight to have accurate radiation detection available to rescue crews in the vicinity and, shockingly, the government's reluctance to admit the gravity of the situation. The whole episode was a tightly knit web of unethical decisions which were taken before, during and after the Chernobyl Nuclear Reactor Explosion.