Aerial view of Asse mine (Photo: BGE)Germany’s Federal Association for Final Storage (BGE) has taken another step towards retrieving the radioactive waste from the former Asse II salt mine in the district of Wolfenbüttel, Lower Saxony.

Between 1967 and 1978, thousands of barrels of mostly low-level radioactive waste were emplaced at the Asse II mine on behalf of the federal government. However, the facility has proven unstable and retrieval of the waste has been legally mandated since 2013.

On 20 December, BGE issued the design and approval planning for the waste treatment plant and the interim storage facility, awarding the contract to a bidding consortium consisting of Uniper Anlagenservice GmbH, Uniper Technologies GmbH and Brenk Systemplanung GmbH. The consortium must submit the plans by the end of 2023.

The contract provides for the creation of the basic assessment, preliminary, draft and approval planning for the waste treatment plant and the interim storage facility. This includes interiors, outdoor facilities, engineering structures and traffic facilities. It covers structural planning and technical equipment for buffering, characterisation, conditioning and interim storage for the radioactive waste to be retrieved from the mine. The goal is an approvable draft and approval planning.

BGE management board chairman Stefan Studt said: “BGE is consistently pushing ahead with planning without creating irrevocable facts. That's how we agreed on it at the end of last year in the so-called lighting process."

According to BGE’s 2020 recovery plan, the contract should provide for the waste treatment plant and interim storage facility to be built in the immediate vicinity of existing company premises. The above-ground systems are to be designed  to handle around 100,000 cubic metres of recovered low and medium-level radioactive waste, including contaminated material. Following conditioning of the radioactive waste, the total volume to be temporarily stored is estimated at around 200,000 cubic metres.  

BGE plans to accommodate the necessary system areas for buffering, characterisation, conditioning and temporary storage in a building complex, taking into account the optimised space and surface requirements. For this, permits are required, among other things, in accordance with the Radiation Protection Act and the Radiation Protection Ordinance. The facility is designed to handle nuclear fuels in accordance with Section 9 of the Atomic Energy Act. The special location in a landscape protection area is also taken into account. The area borders directly on a protected biotope and a nature reserve according to the European Flora-Fauna-Habitat Directive. 

The suggestion of a site close to Asse for a waste treatment plant and interim storage facility was discussed intensively in the region. In February 2021, the Asse-II support group, the Federal Environment Ministry and the Lower Saxony Environment Ministry agreed to review the location decision. The Federal Environment Ministry commissioned four experts to carry out the review. In October they published their report, "Illumination of the site selection process for an interim storage facility as part of the retrieval of radioactive waste from the Asse II mine". 

The report is currently being intensively examined by all parties involved and BGE is re-examining the reasoning for the siting of the waste treatment plant and interim storage facility. However, it was agreed in February 2021 that plans would not be interrupted to avoid any delay to the expected start of retrieval in 2033.  

BGE is a federally owned company within the remit of the Federal Environment Ministry. In April 2017, BGE took over responsibility as operator of the Asse II mine and the Konrad and Morsleben repositories from the Federal Office for Radiation Protection. Other tasks include the search for a repository site to dispose of the highly radioactive waste generated in Germany.

Photo: Aerial view of the Asse II mine (Credit: BGE)