Energy production was shut down at France's oldest nuclear power plant after a pipe defect was discovered.
The plant, which is near the Swiss and German borders, was closed on Saturday due to a flaw in a pipe in the machine room, which does not house nuclear material.
Activists have long campaigned for the plant's permanent closure due to its age. The Fessenheim plant is made up of two 900 megawatt reactors and has been running since 1977, making its France's oldest operating plant.
Greenpeace activists have voiced their complaints to French President François Hollande and German Chancellor Angela Merkel to push Europe towards a real energy transition, rather than depend on either nuclear power, as is the case in France or coal power, as in Germany.
