The Fessenheim Nuclear Power Plant is located in the Fessenheim commune in the Haut-Rhin department in Grand Est in north-eastern France, north east of the Mulhouse urban area, within of the border with Germany, and approximately from Switzerland. Unit 1 was closed in February 2020 and unit 2 on 29 June 2020.
Description The Fessenheim plant has two pressurized water reactors, which each generated 920 MWe. Construction at Fessenheim began in 1970 and the plant was commissioned in 1977. Autorité de sûreté nucléaire, accessed 2009-05-17 It is built alongside the Grand Canal d'Alsace, a canal channelling the Upper Rhine river, from which it drew of cooling water annually.Eléments de diagnostic de la partie française Agence de l'Eau Rhin Meuse, published April 2005, accessed 2011-03-30
The plant employed around 700 staff and 200 contractors,Nucléaire: une année de grands travaux en 2011 à Fessenheim (Haut-Rhin) Décideurs en Région, published 2011, accessed 2011-04-13 and indirectly supports a further 600 to 2,000 people during maintenance operations. The plant contributed around 16,000,000 euro in tax to the various local authorities, including providing the commune of Fessenheim with 70% of its revenue. – Alsapresse.com, published 2006-03-31.
In October 2009 the plant's third 10-yearly inspection on reactor 1 began, in advance of a decision on whether the plant could continue to operate for a further decade.Aire Urbaine | La centrale de Fessenheim est-elle à l’abri d’un accident majeur ? Le Pays, 2011-03-15, accessed 2011-04-13 A full decision was made in 2011, with permission to operate reactor 1 given.French Nuclear Watchdog Plans Fessenheim Decision in ‘Weeks’ Bloomberg, accessed 2011-04-13 Reactor 1 was permanently shut down on February 22, 2020. The second reactor was inspected in mid April 2011.Fessenheim: début lundi de la visite décennale du réacteur N°2 (syndicats) le Parisien, published 2011-04-13, accessed 2011-04-13 The local Information and Oversight Commission asked GSIEN to conduct a parallel independent inspection alongside the official inspection by the Nuclear Safety Authority.GSIEN – Groupement des scientifiques pour l'information sur l'énergie nucléaire Réseau national de mesures de la radioactivité de l'environnement, accessed 2011-04-11 Reactor 2 shut down on 29 June 2020.
Technical data
Unit Type / Model Net Capacity Gross Capacity Thermal Capacity Construction Start First Criticality Grid Connection Commercial Operation Permanent Shutdown Fessen-heim 1 PWR / CP0 880 MW 920 MW 2785 MW 1971-09-01 1977-02-07 1977-04-06 1978-01-01 2020-02-22 Fessen-heim 2 PWR / CP0 880 MW 920 MW 2785 MW 1972-02-01 1977-06-27 1977-10-07 1978-04-01 2020-06-30
Selected incidents and accidents On April 9, 2014, a tank on the non-nuclear equipment cooling system was accidentally overfilled due to incorrect level indicators. As the overflow drain pipe on this tank was blocked near ground level and could not drain the overflow water as designed, the overflowing water from this tank backed up through multiple other pipes and eventually began overflowing into a room next to Unit 1's control room. The failure of several supposedly water-tight seals between floors allowed the leaking water to descend into lower levels, eventually encountering and shorting out electrical equipment used for some of the nuclear control systems. One of the two redundant reactor protection system trains became unavailable due to the water damage, and the reactor control rod visual position indicators were totally disabled. Although by this point the water leak had already been stopped, the loss of the reactor control rod visual position indicators meant that the reactor could not be shut down via normal control rod operation, and would need to be shut down through an alternate system (either via an uncontrolled emergency drop of the safety shutdown rods or by utilizing the boron injection system). The operators on duty chose to slowly bring the reactor to a normal shutdown via the use of the boron injection system (which was permitted under normal operation rules), and the reactor reached a "maintenance cold shutdown" state on April 11, 2014. This event was rated at 'level 1' on the International Nuclear Event Scale (INES). Following the repair, testing, and recertification of all damaged equipment, Unit 1 was subsequently reconnected to the grid on May 28, 2014. On September 5, 2012, two employees were mildly injured by a steam release caused by a minor chemical accident which also triggered fire alarms at the plant. On April 10, 2011, operator error led to one of the reactors automatically shutting down. The incident had no further consequences and was rated at 'level 1' on the International Nuclear Event Scale (INES).Centrale de Fessenheim: une manœuvre cause un incident nucléaire de niveau 1 Tribune de Genève, published 2011-04-08, accessed 2011-04-12 On December 27, 2009, a 'level 1' incident on the INES occurred when plant matter was drawn into the Essential Service Water System intake, reducing the flow rate, although the flow remained sufficient to avoid endangering the security of the plant.Communiqué n°2 à 17h15 – Incident en voie de résolution à la centrale nucléaire de Fessenheim, published 2009-12-27, accessed 2011-03-30 On January 24, 2004, the water in the primary circuit water of Unit 1 was contaminated by radioactive resin from a system used to filter out boron, quickly blocking several filters and endangering the integrity of the joints on the pumps.Incident à la centrale de Fessenheim IRSN, published 2004-02-10 accessed 2011-03-30Tranche 1 De La Centrale Nucleaire De Fessenheim Incidents De Janvier 2004 Stop Transports, accessed 2011-03-30 Seven EDF employees inhaled radioactive dust during the replacement of the filters, and another was slightly irradiated during the clean-up the following month. The incident was categorised at 'level 1' on the INES.Les cahiers de Global Chance – N° 25 – septembre 2008 Global Chance, published September 2008, accessed 2011-03-30
Risks Due to its location, the Fessenheim plant is subject to particular risks from seismic activity and flooding, and there is an ongoing debate about the adequacy of its design in these respects.
Seismicity
The majority of the Haut-Rhin département, including Fessenheim, is classified as being in a zone of moderate seismicity; the southern third is in a medium-risk zone.Quatre centrales sur une zone sismique Les quatre éléments published 2011-03-15, accessed 2011-04-13 The most recent earthquake in this zone, with a magnitude of 3.9, took place on Saturday, 10 September 2022, 1.2km from Flaxlanden (epicenter 47.693°N 7.359°E with a 8.9 km depth). Previously an earthquake of magnitude 4.7, was recorded in this southern third at Sierentz in July 1980. The last major earthquake in the region was the 1356 Basel earthquake, estimated to have had a Mw magnitude of up to 7.1.Centrale Nucléaire de Fessenheim : appréciation du risque sismique Résonance Ingénieurs-Conseils SA, published 2007-09-05, accessed 2011-03-30
A report commissioned by the Swiss canton of Basel-Stadt, published in 2007, concluded that the previous seismic evaluations undertaken by both EDF and, to a lesser extent, by the Institut de radioprotection et de sûreté nucléaire (Radioprotection and Nuclear Safety Institute, IRSN) had underestimated the risks involved. In particular, although the location of the fault in the Rhine Rift Valley that led to the 1356 Basel earthquake was sufficiently well known for national and regional purposes, its location was not known precisely enough to evaluate a particular site. Studies conducted by other scientists have, for example, reached different conclusions about which faults might have been involved in the 1356 earthquake, its magnitude (ranging from 6.0 to 7.1 on the moment magnitude scale), and the distance from the fault to the plant (ranging from to away, compared to the distances of and used by EDF and the IRSN respectively). EDF also failed to take into account the possibility of a moderate local earthquake, which may have the potential to do greater damage than one which is larger but more distant, and the report was also critical of some aspects of the RFS 2001-01 assessment requirements. The report found that the design standards in force when the plant was built were similar to those that apply to present-day public buildings: the plant had been designed to accommodate movement, but it was not possible to determine whether or not the safety margins used would be adequate if a more realistic seismic evaluation were to be used.
On March 11, 2011, the local Information and Oversight Commission announced that it was commissioning two independent second opinions, to be delivered as soon as possible, one on 'the safety of the plant in the event of an earthquake of magnitude 7.2, corresponding to the new seismic reference point proposed by the Swiss experts', the other on the 'redundancy of the cooling systems' in case of flooding.Centrale de Fessenheim : la CLIS demande deux nouvelles contre-expertises Le Parisien, published 2011-04-11, accessed 2011-04-11 GSIEN has been commissioned to produce one of the reports.Alsace | Fessenheim : contre- expertises et nouvelles études L'Alsace, published 2011-04-11, accessed 2011-04-11
Flood Although situated around below the level of the adjacent Grand Canal d'Alsace, it is not clear whether, taking into account the calculation methods in the 1960s, the design took adequate account the consequences of a breach in the canal. In its initial report following the 1999 Blayais Nuclear Power Plant flood, the Institute for Nuclear Protection and Safety (now part of the Radioprotection and Nuclear Safety Institute) called for the risk of flooding at Fessenheim to be re-examined due to the presence of the canal.Rapport sur l'inondation du site du Blayais survenue le 27 décembre 1999 Institute for Nuclear Protection and Safety, published 2000-01-17, accessed 2011-03-21
On March 11, 2011, the local Information and Oversight Commission announced that it had commissioned an urgent report on the 'redundancy of the cooling systems' in case of flooding and that another report 'to determine the areas to strengthen to guarantee the safety of the plant in the event of a breach in the canal', which had already started, was expected in June 2011.Fessenheim : contre-expertises demandées France 3, published 2011-04-11, accessed 2011-04-11
Aquifer The station is built on top of a large aquifer (French Fossé rhénan, German Oberrhein-Aquifer), contamination of which would be very harmful. A concrete slab is built below the reactor in order to reduce the risk of polluting the aquifer.
Cooling water In August 2018, the plant was shut down during a heat wave to ensure that cooling water being released into the nearby river did not overheat it.
Opposition Opposition to the Fessenheim plant dates back to the 1970s when its construction was proposed, and in June 1977 the pirate radio station Radio Verte Fessenheim (Green Radio Fessenheim) began broadcasting against the plant. Internationale Rundfunk und Fernseh-Chronik, accessed 2011-04-14