Annual simulation of the Ascó nuclear power plant
This Thursday morning, the Ascó nuclear power plant carried out its annual drill within the facility’s internal emergency plan. The exercise consisted of simulating the effects on the two units of an earthquake that would have caused the declaration of category 4 of the plan and the actions described in the procedures. External radiological emissions and the internal loss of communications have also been simulated. This drill was conducted from the Alternative Emergency Management Center (CAGE), an installation incorporated into the plant in the context of the improvements introduced to the state nuclear park following the accident at Fukushima Daiichi (Japan).
New unscheduled stop at the Ascó I unit
On the other hand, the Ascó I nuclear power plant has notified a new unscheduled shutdown of the unit for intervention in the main feed water control valve, which corresponds to steam generator C. The Nuclear Safety Council (CSN) has assured that the incident has had no impact on the safety of the facility, people or the environment. All the security systems have acted according to their design and the plant is in a “stable” situation, as reported by the CSN in a statement. At the beginning of April, there was already a similar stoppage. This event is classified as level 0 on the International Scale of Nuclear and Radiological Events (INES).
Decision to stop the plant
According to the CSN, the owner of the Ascó I nuclear power plant has taken the decision to stop the plant after observing oscillations in the speed of the two main feed water turbopumps (TBBAA), derived from ‘a high pressure in its discharge and after verifying that it was not corrected with the lowest power (70%). After analyzing the situation, its managers have decided to reduce the power of the plant to make an orderly shutdown and solve the problem. During the checks, they identified that the “real” position of the affected valve did not match the required one, therefore, “they deduce that the valve actuator was not in the original position and that it should have moved since last check”.