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Koeberg has a series of lines of defence to ensure safety:
Safety codes require independent off-site sources of power. Koeberg has the national grid (400kV and 132kV lines into the station) plus a dedicated 132kV powerline to the three gas turbines at Acacia, near Monte Vista/Edgemead.
Should these off-site sources fail simultaneously, the codes require independent on-site power sources. Koeberg has two diesels dedicated to each reactor, which is the French standard, plus a fifth "swing"' diesel, which can be connected to either reactor. By design, the five diesels are entirely independent.
Any one diesel can supply sufficient emergency power for one reactor, including its associated spent fuel pool.
Should all the diesels somehow fail, the auxiliary feedwater system will continue to cool the core. It is steam-driven by heat still being generated in the shut-down reactor and does not need electric power. After a minimum of 10 hours' operation, the AFS water supply may have to be topped up and this can be done by various means.
If these standard procedures fail, emergency procedures maintained in the Koeberg control room and the technical support centre detail many other "non-standard" ways of injecting water into the reactor or, just as effectively, into the steam generators.
The safety systems at Koeberg MUST be operated from a power source outside Koeberg, otherwise when Koeberg has a problem, the safety systems cannot function. The default condition of Koeberg's safety systems is with the control rods removed from the reactor. So, when power is interrupted to the safety systems, the control rods are automatically removed from the reactor, which shuts it down. A good thing too, as running a nuclear reactor without any safety systems is dangerous business!
This means that when there is a disruption on the external power supply, Koeberg automatically shuts down. It is what is known as a "fail safe" system. It takes as much as 5 days to restart the reactor after it is shut down by the failsafe. This means that the Western Cape has several days of insufficient power to endure until the reactor is back on line and generating power.
Security at Koeberg is governed by the National Key Points legislation, which is dealt with by the security forces.
Television cameras which are connected directly with the International Atomic Energy Agency (IAEA) in Switzerland, have been installed in nearly every room.
In 1948 the Atomic Energy Act created the Atomic Energy Corporation (AEC). In 1963 the Nuclear Installations Act provided for licensing and in 1982 the Nuclear Energy Act made the AEC responsible for all nuclear matters including enrichment. An amendment to it created the autonomous Council for Nuclear Safety, responsible for licensing.
The Nuclear Energy Act of 1999 gives responsibility to the Minister of Minerals & Energy for nuclear power generation, management of radioactive wastes and the country's international commitments.
The National Nuclear Regulator Act of 1999 sets up the National Nuclear Regulator (previously the Council for Nuclear Safety) covering the full fuel cycle from mining to waste disposal. It is focused on health and safety.