Mochovce NPP: Coronavirus countermeasures will affect the planned general overhaul

Mochovce NPP: Coronavirus countermeasures will affect the planned general overhaul
In 2020, the series of general overhauls (GO) of Slovak nuclear units starts at the Mochovce NPP Unit 1 on Saturday, 28 March.

Due to the measures the Company introduced against the spread of coronavirus, the biggest electricity producer in Slovakia will execute only the most important works during the planned general overhaul, based on approval by the Slovak Nuclear Regulatory Authority, hence minimising the number of people or their social interaction in the nuclear power plant premises.

Overhaul goal

The main goal of the Mochovce nuclear power plant GO is to replace about one fifth of the fuel in the reactor and to carry out repairs and investment projects to increase the plant‘s safety. Works on this year's GO are reduced, but the length remains unchanged and should take less than three weeks.

The crucial activities include works at important technical water system (water for cooling of systems important for nuclear safety), emergency core cooling systems, and electrical substations. Non-destructive inspections, inspections of heterogeneous weld joints of one of six steam generators, and overhaul of one reactor coolant pump are also planned.

Works during pandemic

As a consequence of coronavirus measures, some of the initially planned investment projects will be implemented in a limited scope. However, the planned works related to seismic reinforcement project will be done in full extent. As for the severe accident management project, which has already been completed, the outage will include planned regular revisions, inspections and tests of equipment.

Working shifts of the staff were also changed from 8 to 12 hours to reduce employee rotation and thus also the risk of potential coronavirus spread. The adopted modifications will not affect safety or reliability of the plant's operation and were discussed and approved by the Nuclear Regulatory Authority of the Slovak Republic.

In March, Mochovce and all other power plants of Slovenské elektráne introduced mandatory contactless temperature measurement at the plants' entry points. After passing through the thermal camera checkpoint, each entrant must sign a declaration on clinical symptoms and his or her travel history. There are disinfection stations at all busy places of the power plant, it is obligatory to wear face masks, which are even sewn by the plant laundry employees and volunteers who work from home office. In closed spaces, such as control rooms, Slovenske elektrarne deployed germicidal UV lamps.

„We have adjusted the scope only to the necessary activities that we will ensure with in-house capacities. In addition to the generally applied measures to prevent the spread of coronavirus we have introduced also specific measures to workers who take part at the overhaul. Conservatively, we don not plan to use all our capacities, and so having a reserve in place if we had to quarantine some employees.“

Miroslav Tokár
Director of the Nuclear Power Plant Division
Slovenské elektrárne, a.s.

The Unit 1 general overhaul in Mochovce will be followed in mid-May by general overhaul of Bohunice NPP Unit 4. Bohunice Unit 3 will be shut down in the second half of June and the marathon of overhauls will be completed in September by Mochovce Unit 2 general overhaul.