Above: Angarsk Electrochemical Plant (Image courtesy AECC)

 

ROSATOM, RUSSIA’S STATE NUCLEAR CORPORATION, had recently planned a tender to select a contractor to decommission a building at the Angarsk Electrochemical Plant (AECC) in Irkutsk. The initial tender price for the work, on building No 802, was RUB973 million ($13.2 million). In the event, the tender was dropped and AECC itself undertook responsibility for the work, having earlier successfully decommissioned another large building — No 804 — at the site.

AECC will have to complete the work before 30 November 2022. Among the tasks, as specified in the original tender, are developing process control cards to confirm acceptability criteria for burial, dismantling ventilation outlets, accepting building 804/1 from the operating organisation, removing equipment from conservation, commissioning, rehabilitation of the territory within the boundaries of the excavated foundation pit buildings and more.

AECC is part of Rosatom’s fuel company TVEL. It was established in 1957 to undertake uranium enrichment and conversion. Two buildings (802 and 804), which housed gaseous diffusion uranium enrichment facilities, were shut down in 1987 and 1990, respectively, after Russia switched to gas centrifuge technology.

The company began decommissioning building 804 in 2016 within the framework of the federal target programme “Nuclear and Radiation Safety in 2016-2020 and until 2030” (FTP NRS-2). The project was titled “Decommissioning of Building 2 (Building No. 802) and Building 4 (Building No. 804) at AECC”. Decommissioning also included warehouse 35.

The total area of the facilities involved was more than 176,000 square metres. Previously, building 804, which was around one kilometre in length, housed a uranium enrichment plant using diffusion equipment. Two general contractors were appointed to undertake the initial work — FSUE “Radon” and JSC UDC PEM — with funding from the Russian federal budget. This entailed construction of a temporary site for radioactive waste management, organisation of access roads, installation of electricity supply networks and a transformer substation, construction of temporary storage sites for general waste and creation of an additional physical protection perimeter.

By the end of 2019, more than 4500 tonnes of equipment had been dismantled and decontaminated. Pure metal was sold on the market, with metal processing enterprises in the Irkutsk region acting as buyers.

“Before the start of the project, an engineering radiation survey was carried out, project documentation was prepared, which passed a sanitary and epidemiological examination, EIA (Environmental Impact Assessment) documents were prepared by independent experts and public discussions were held, and a licence was issued by Rostekhnadzor for the work,” said AECC general director Alexander Dudin.

“When analysing building structures, radiation monitoring is constantly carried out. Waste is classified,” he added. “Dismantling of building 804 is almost complete. Contaminated metal structures and construction waste have been deactivated, compacted, packaged in safe containers and handed over to the National Operator for Radioactive Waste Management (FSUE NO RAO) for placement at the radioactive waste final isolation point. More than 100 cubic metres have already been transferred.”

Current activities at the site

Conversion activities ceased at Angarsk in 2014. In 2011 TVEL began implementing a programme to concentrate Russian conversion capacities at the Siberian Chemical Combine (SCC) in Seversk. In the wake of this decision, AECC underwent restructuring aimed at increasing production efficiency and reducing production costs. Several auxiliary divisions of the plant were outsourced, including a dispensary, an industrial hygiene workshop, the car fleet, a repair and construction workshop, a food workshop and the communication department. The Palace of Culture and the Sports Hall were transferred to become municipal property, and the recreation camp was transferred to the ownership of the regional authorities.

While the main activity of AECC remains the production of enriched uranium hexafluoride, the company is also developing new non-nuclear business areas. Potassium bifluoride production is being launched, a joint venture is being created to produce silicon carbide and micro- powders based on it, research work has been done to create a new lithium hydroxide production line, and a joint venture between AECC and QSIL GmbH (Germany) has been created to produce highly pure quartz crystals.

In September 2018, TVEL and the Irkutsk Region signed a road map for the creation of an industrial park at the AECC site. The road map was adopted following the working meeting of Natalia Nikipelova, the president of TVEL, and Sergey Levchenko, the governor of the Irkutsk Region. The document aims to consolidate the strategic partnership between TVEL and the Irkutsk Region, which began with an Agreement of Intent to attract investors and residents to AECC to create new non-nuclear industries. TVEL is seeking not only to boost its presence in the nuclear market, but also to develop new types of business. “We are open for cooperation in the field of additive technologies, the production of energy storage devices, superconducting materials, special chemistry and metallurgy, as well as other areas,” said Nikipelova. “For us, this is not just business, but also an integral part of our social responsibility in the regions of our presence.”

Since December 2014, the separation plant at AECC has switched to the “mine” mode. The plant now extracts uranium-235 suitable for use in nuclear reactors from depleted uranium hexafluoride (DUHF) accumulated over the years the plant was active and stored at the site. The existing reserves are expected to be sufficient to allow such work to continue until 2035. The material is then transported to TVEL’s Electrochemical Plant in Zelenogorsk (Krasnoyarsk Territory) for further transfer to a safe storage form, following defluorination.

Dudin insisted that the storage of DUHF at AECC “does not pose a threat to the staff, population and environment of the region”. He explained that the DUHF ”is not a radioactive waste, but is considered as a valuable energy resource for future nuclear energy”. He said the concentration of radioactive uranium-235 in the composition of DUHF is so small (no more than 1%) that no restrictions on nuclear safety are needed when storing packages in open storage areas.

He added, “The practice of storing DUHF in open areas is global and recognised by the International Atomic Energy Agency. DUHF is stored in special containers whose walls are about 10 mm thick. The results of the studies confirm that the service life of containers for storage of DUHF is more than 80 years…. To prevent corrosion, containers are sprayed annually with cold gas-dynamic spraying and gas-thermal methods using polyurethane aluminium-zinc containing coatings.”

AECC also hosts the International Uranium Enrichment Centre (IUEC), which was set up in 2007 under the auspices of the International Atomic Energy Agency (IAEA). Russia proposed creating a guaranteed reserve of low enriched uranium (LEU) to be controlled by the IAEA, which could be used by member states unable to procure LEU from the open market for political reasons. The IUEC also provides uranium enrichment services to non-nuclear states. Enriched uranium is used for the manufacture of fuel assemblies and for the supply of nuclear fuel to the shareholder countries. The original shareholders of IUEC were Rosatom (50% plus 1 share), Kazatomprom (Kazakhstan, 10%), Nuclear Fuel Group (Ukraine, 10%) and the Armenian nuclear power plant CJSC (Armenia, 10%). Kazakhstan withdrew from IUEC earlier this year.

Author information: Judith Perera, Contributing Editor, Nuclear Engineering International