The Stocamine company is a subsidiary of the Mines de potasse d’Alsace (MDPA), created to transform the former salt mine into a storage site for class 1 (hazardous) and class 0 (highly toxic) final waste, making this site the only one authorized to receive this type of waste on French soil. From 1999 to 2002 some 42,000 tonnes of waste were thus received in the municipality of Wittelsheim (Haut-Rhin) and stored approximately 500 meters underground.
In 2002, a fire put an end to this activity and raised the question of the final containment or the removal of the storage of the toxic waste that had been stored. The debate has been raging for 20 years because the first underground water reserve in Europe would be threatened. Indeed, the site of the old mine is located under the Alsace water table, which extends widely into Germany and Switzerland, and constitutes one of the largest reserves of drinking water in Europe. Is this a very real risk and what are the real issues?
A quickly ruined project
This project was born in the early 1990s as part of the conversion of historic potash mining activities in Alsace, an activity whose operation was to end in 2004 after having employed around 10,000 people for several decades. Even if its ambitions in terms of jobs are modest (a hundred jobs are planned), the planned storage activity appears to be a breath of fresh air in a labor market in great difficulty.
Stocamine was therefore created in 1991 with the main shareholder EMC, which is a public industrial and commercial establishment that also owns MDPA. The project was set up gradually between 1991 and 1997 andauthorization to use the site is the subject of a prefectural decree dated February 3, 1997 laying down the conditions that this operation must respect: the authorization is given for a maximum period of 30 years, after which a new authorization must be requested to continue the activity, or, failing that, at the end of which stored waste must be removed from storage.
Effective waste storage started in February 1999 with a storage target of 50,000 tonnes of waste per year. The rise in power is not as rapid as anticipated since the site will only receive 16,000 tonnes of waste in 2001, which will prove to be the peak of its activity. Indeed, the inThe burning of a block of waste, which occurred in September 2002, will modify the course of events and bring Stocamine into the closed circle of state affairs.
The reasons for failure
This fire is the consequence of shortcomings and major breaches occurring at different levels, as demonstrated by the judicial inquiry opened on this occasion and the judgment of the Mulhouse tribunal de grande instance of January 28, 2007, confirmed by the Colmar Court of Appeal in 1999condemning the company and its management for the offense of endangering others by manifestly deliberate violation of the prescriptions of the prefectural operating order. The origin of the drama comes mainly from a lack of strict control of the waste before its admission for storage. In fact, the admission procedure was based solely on the declarations made by the companies shipping the waste and a statistical check covering only a small part of the samples.
More specifically, the checks did not make it possible to rule out a batch of waste from the Solupack company, which nevertheless appeared to be non-compliant, and is considered to be the very probable cause of the fire. The way in which the batch of waste from Solupack was managed could also be linked to Stocamine’s profitability issue. Indeed, as we have seen, the volume of waste received was much lower than anticipated, and this lack of volume may have led the company to accept certain deposits without giving them all the necessary rigor.
From failure to scandal
The consequences of the 2002 fire, which took 2 months to be brought under control, are multiple. Indeed, since this event and the ensuing investigations, most of the certainties erected at the time of the launch of the project have proven to be shaky. The first is Stocamine’s inability to ensure control and traceability of the waste actually stored underground. This means concretely that no one really knows the nature and quantity of the products that are found today under the Alsatian water table.
The second is the company’s inability to guarantee the reversibility of the disposal of the stored waste. This point was however indeed an essential point put forward during the publication of the prefectoral operating order (article 2). Indeed, this reversibility is undermined by the insufficient quality of the envelopes (pallets and bags) containing the waste, which does not always seem sufficient to ensure destocking under good safety conditions. But even more this reversibility is made difficult by the deformation of the galleries beyond the initial anticipations. The technical analyzes carried out successively over the last few years on this subject have made it possible to confirm a risk of pollution of the water table due to the foreseeable flooding of the galleries of the mine and the rise of part of the pollution towards the groundwater.
The modeling of this risk, the occurrence of which seems to have been underestimated at the start of the project, is poorly controlled, and its occurrence is difficult to assess over time (the various studies on the subject indicate that flooding could occur in 70 to 500 years, but agree on the fact that this flooding seems inevitable). The exposure of the population and the environment to this risk is such, because of its potential seriousness, that it has been at the center of debate since 2007.
Errare humanum est, perseverare diabolicum
The previous information, gradually brought to the attention of the public and of local political decision-makers, broke the trust placed in the company. The lawsuit brought against Stocamine and its management between 2002 and 2007 and the convictions decided by the courts also contributed to depriving it of all credibility, as well as the State and its control bodies, for the management of the extinction of the activity decided following this crisis.
A certain number of technical studies have been carried out since 2007 in order to determine possible scenarios for the management of the 42,000 tonnes of waste stored in the mine. These scenarios essentially focused on the possibility of permanently confining the waste underground or on the possibility of extracting it in order to avoid any risk to the water table.
In June 2010, a report commissioned by the government revealed an intermediate solution advocating only removing the most dangerous products and confining other waste. It is on the basis of these proposals that the government decided in 2012 to destock some of the waste containing mercury and to contain other waste.
It nevertheless took no less than 5 years, 2 additional public inquiries and an expertise of the closure file submitted to the authorities before the prefectural decree of March 23, 2017 authorized the storage of waste for an unlimited period after removal of the waste containing mercury and certain phytosanitary wastes.
This was without counting on the legal action brought by the Haut-Rhin department, the Grand-Est region, the Alsace Nature association and the municipality of Wittenheim, asking the administrative court of Strasbourg to cancel this decree, account taking into account the risks identified and the alternative solutions that it seems possible to put in place. Initially dismissed (decision of June 5, 2019 of the Administrative Court of Strasbourg), the plaintiffs will win their case on appeal (decision of October 15, 2021 of the Court of Appeal of Nancy) before the State seizes the council of State, which will reject its appeal on September 29, 2022.
The cancellation of the waste landfill authorization decided in 2017 becomes final. The State must now resort to a new environmental assessment procedure if it wishes to confirm its decision to permanently bury the waste.
State behavior that creates confusion
20 years after the fire that put an end to Stocamine’s activity, the situation has hardly changed. A very small part of the waste has been removed in recent years, but precious time has been lost, making waste disposal increasingly difficult.
The most recent studies have shown that a period of 7 to 15 years would be necessary to evacuate all the waste that had been stored between 1999 and 2002. Most of this waste would therefore have already been evacuated or would be about to be be if that decision had been made.
In practice, the State has continued to delay the deadlines with an almost obsessive desire to permanently bury this highly toxic waste, despite the proven risk of polluting the largest groundwater table in Europe in the more or less long term. This attitude only strengthened the position of those in favor of destocking, by helping to create the feeling that the waste should under no circumstances be brought to the surface.
Worse still, the voice of the State is no longer audible, which appears extremely detrimental at a time when the storage of nuclear waste in deep geological layers represents, in a similar field, a major challenge for the coming decades and will have to be treated with transparency in order to restore the confidence of the population and elected officials.
Arnaud Allemann (MSIE 40 from EGE)