Possible aircraft attack
There has been a lot of contemplation over the consequences of occurrence of an attack by a large aircraft similar to the 2001 World Trade Centre attack in New York. This time the target being a nuclear facility aiming at radioactive materials. Studies show that nuclear reactors would be robust as compared to any other civil installations used to resist such attacks. A thorough study financed by the US department of Energy and conducted by US Electric Power Research Institute (EPRI) concluded that the US reactor would be strong enough to withstand attacks from large commercial aircraft.
A fully fueled Boeing 767-400 weighing over 200 metric tons and flying at its precision speed of 560 km/h close to the ground was used as the basis of the study. The wingspan of this plane was greater than the diameter of reactor containment buildings and has 4.3 metric ton engines 15 meters apart. The analysis used two approaches to assess the impacts of the attacks. First, they focused on the impact of a single engine because this would be the most direct and detrimental missile on the centerline of the containment building. Secondly, they assessed the what-ifs of the entire aircraft when its fuselage made a direct hit on the centerline of the containment building, in which the engines would ricochet off the fuselage. In both cases, no part of the aircraft, no matter how hard it hit the centerline, penetrated the containment and other studies affirmed this fact.
Penetrating reinforced concrete is not as simple as it seems, it has a lot of impediments that the terrorists wouldn’t even lay their hands on. For instance, even a relatively weak reinforced concrete would only succumb to high-speed artillery shells or specially designed “bunker busting” ordnance. An aircraft hitting the containment heavily-reinforced concrete would immediately disintegrate with little or no impact on the containment reactors. Findings documented by EPRI in 1981 reported that a lot of testing are in place to assess the implications of even the worst possible realistic chances of core melting and containment failure would cause very negligible if any to the public no matter the cause of the containment failure.
By 1988, there were extensive testing to prove that a nuclear plant would stand the impacts of a massive aircraft attack and Sandia National Laboratories in the US was tasked with the duty of demonstrating the unequal distribution of energy absorption when a large aircraft hit a hardened target. This was to see if a proposed Japanese nuclear power plant would stand the impacts of an aircraft attack. For this demo, they used a rocket propelled a 27-metric ton F4 Phantom jet which had both engines close to its fuselage, would hit hard on a 7m thick slab at a fast speed of 765 km/h. Most of the impacts went to the destruction of the aircraft itself, actually about 96% of the kinetic energy within the aircraft was responsible for its own destruction and slightly on the penetration of the concrete while the other remaining about 4% was lost off trying to penetrate the 700-tonne slab. The maximum damage on this experiment was only a slight 60 mm.
As early as the late 1970s, there were already conclusions put in place by the UK Central Electricity Generating Board on the possibilities of a fully laden and fully fueled large passenger aircraft deliberately slamming into a nuclear reactor as a consequence of a hijack. They deduced that no possible or foreseen damage would happen to the nuclear reactor since the aircraft would crash up on the many obstacle buildings and concrete even before reaching the concrete biological shield surrounding the reactor. By the 1980s, there were already plants in the US that were structured and deigned to literally stand the hard hits of a fully laden large military transport aircraft and maintain a cold shutdown with precision.
Security measures
The US has always been proactive in matters of security measures brought about by the mishaps of such events and has put up very stern security measures. The US Nuclear Regulatory Commission is mandated to oversee these measures and require that any nuclear power plant should have laid out measures to ensure the safety of the public from danger of radioactive elements in case of any breach in the plant. It requires plants to setup barriers, a non-penetrative security station as well as the physical structure to be strong enough; all these would sum up to $2 billion to the industry. Anyway, these regulations check on:
- The building in which the reactor containment segment is
- Security personnel and surveillance of the premises
- Safety and security clearance of plant employees
The construction and structure of the building
The reactor containment buildings are designed to withstand any form of danger. With a lot of reinforced concrete coupled with a number of safety shutdown systems that are able to withstand even the trials of hurricanes, floods, aircraft attacks or even tornadoes, these buildings are constructed in such a way that they become resilient and withstand any physical catastrophe or threat.
The physical requirements of the barricade should be composed of thick layers of concrete reinforced with steel in order to ensure maximum safety. These concrete barricades are in layers in which they protect the radioactive nuclear elements.
Security force and personnel
The US Nuclear Regulatory Commission requires that each and every nuclear plant should deploy well trained and well-armed security guards that cover the grounds with very tight security each and every minute of the day. Also, there must be hi-tech electronic surveillance that works hand in hand with the security personnel in taking cover of the nuclear plant.
Periodic tests and mock drills are should be conducted by the plant to demonstrate that the plant can withstand raids of well-trained paramilitary force. These mocks are conducted in such a way that they resemble the real-life scenario in which the plant might be under attack or siege, and the plant security personnel should disable this threat. The attackers would be in possession of weapons and explosives trying to break in and it is upon the security to end the attack. The mock drills are conducted under the supervision of Nuclear Regulatory Commission where they assume to have an insider within the plant that feeds the attackers with vital information on the equipment within the plant. The Nuclear Regulatory Commission assesses the drill and if they require any necessary reinforcements to the already existing security measure, they advise from the results of such a drill.
Nuclear power plant protection from internal threats
The nuclear power plant might have threats from within in that plant personnel might be part of a terrorist group or might be aiding in the same course. So, the Nuclear Regulatory Commission ensures that plants have programs in place to avoid any such instance. It requires that energy companies should conduct impromptu drug tests to at least half of its employees annually. Employees pass a very strict background checks evaluating their education, psychological, criminal and drug related histories for starters. New employees and contractors are subjected to a mandatory drugs and alcohol screening tests which they must pass to be considered fit to work.
The US Federal Bureau of Investigation goes ahead to classify nuclear plants as ‘hardened’ targets because of the rigorous security measures and activities put in place in the maintenance of the premises.
There was a study conducted in the 1970s examining the possible effects in case a terrorist attack was successful and caused a breach in the containment structure and a meltdown in the core, in which such an occurrence would never happen. The study showed that these radioactive materials would stick on to the surface of the containment or become soluble salts trapped in the remnants of the containment building. Though there were some radioactive materials that would escape the containment reactor that would still reach the general population, and it is only under such an extreme situation, and only under these rare conditions. This damage would only affect a small population on several kilometers from the plant facilities.
Wrap up
While there were already robust structures put in place to withstand the tests of attacks by the start of the 21st century, the 2001 attack was an eye-opener that led to reinforcement in the security measure and oversight of NRC on such plants. The various studies in place have time and again depicted that these reactors would stand the ultimate force of any attack and would retain all its radioactive elements untouched, even under the attack of any paramilitary sabotage on the plants, giving more people peace of mind. Clearly, the massive structures that are already in place would be very hard for terrorists to even try to attack, even if they attack, they would cause little or no damage to the physical structure itself. The radioactive element will be safely protected and such attacks would not result in any radioactive releases.