IAEA showcases environmental remediation success

It is now common practice to take environmental impacts and plans for remediation into account when planning and designing new projects, IAEA Deputy Director Mikhail Chudakov said in his opening address to a side event at the Agency's 63rd General Conference which took place in Vienna in September. However, many legacy sites around the world require decontamination and remediation, including mining, fuel cycle, military and research sites and also sites contaminated with naturally occurring radioactive materials (NORM). The IAEA will hold its first International Conference on the Management of Naturally Occurring Radioactive Material (NORM) in Industry in October 2020.

Decontamination and remediation projects for legacy sites are themselves national initiatives, but can face a lack of infrastructure and suitable human resources, Christope Xerri, director of the nuclear fuel cycle and waste technology division at the IAEA's Department of Nuclear Energy, said. The IAEA's role is to provide support by enabling staff to work together, he said. It does this by sharing and disseminating knowledge and building capacity to address common challenges using, for example, IAEA publications, dedicated programmes, peer review missions, and technical support and networking in a holistic approach involving both the IAEA's Technical Cooperation and Peaceful Uses initiatives.

The Agency's Technical Cooperation department has since 1995 supported 31 national decommissioning and environmental remediation projects of which 14 were to assist member states in decommissioning and 17 in environmental remediation, Ana Raffo-Caiado, director of the European division of the IAEA's Department of Tehcnical Cooperation, said. It has also supported 16 regional projects - seven in decommissioning and nine in remediation, and two inter-regional projects. Some 348 expert missions, 147 meetings and workshops, 77 training courses, 196 scientific visits and 339 Fellowships have been carried out.

Over the period 2020-2021, the IAEA Technical Cooperation programme expects to support 11 new decommissioning and environmental remediation projects with an estimated total budget of EUR5.9 million (USD6.4 million), she said. These include nine national projects and two inter-regional projects. It also expects to support 16 new radioactive waste management projects with a total estimated budget of EUR5.8 million.

NORM in Azerbaijan

An example of a project where the IAEA has provided support for remediation work is at NORM-contaminated sites related to former iodine-bromine production facilities in Azerbaijan. Iodine and bromine were extracted from oilfield water pumped out in conjunction with oil production, and extracted by adsorption on activated charcoal at three sites established from the 1930s onwards. Two of the sites remained active until the 1990s and one until 2004.

Substances left behind in the charcoal after the recovery of iodine and bromine included naturally occurring radium and its decay products. This resulted in site contamination from heaps of processed charcoal containing harmful substances such as chemicals and oil as well as radium compounds, said Vugar Husseynov, of Azerbaijan's State Agency for Nuclear and Radiological Activity Regulation. Additionally, the sites contained the remains of similarly contaminated equipment; soil polluted by oil and oil products, bitumen and crude oil; NORM-contaminated asbestos tubes from underground communications; contaminated scale on walls; and slightly contaminated construction debris.

Remediation of the iodine and bromine production sites at Ramany, Surakhany and Neftchala was the first such project ever to be implemented in Azerbaijan. Technical cooperation with the IAEA was seen as a way of overcoming a lack of experience in such remediation projects, Husseynov said. IAEA support was provided under two Technical Cooperation programmes, the first of which began in 2007. Expert missions under those programmes addressed, amongst other things: the formulation of remediation options; international standards and methodologies; planning for the disposal of NORM waste; technical support and recommendation for rehabilitation of production sites; and surface radiological characterisation of remediated sites.

The sites of the three iodine-bromine production plants, which cover a total area of 48.7 hectares, have now been decontaminated and rehabilitated, Husseynov said. About 400,000 cubic metres of NORM-contaminated waste has been removed from the sites and disposed at a newly built disposal facility, and the land has been rehabilitated and returned for economic activities.

Management of NORM wastes in the oil production industry continues to be a major area of technical cooperation between Azerbaijan and the IAEA, Husseynov said. Decontamination of a buffer lake adjacent to one of the rehabilitated sites will be the next challenge.

Chernobyl pond remediation

 
A project to remediate a cooling pond which was heavily contaminated with radionuclides following the 1986 accident at the Chernobyl nuclear power plant also received support from the IAEA. During the plant's operation, the pond, which lay between the plant and the Pripyat River, covered an area of nearly 23 square kilometres and held 150 million cubic metres of water.

After the final operating unit at Chernobyl closed in 2000 such a large body of water was no longer required, and the pond's water feed from the river was halted in 2015. However there remained concerns that decommissioning the pond may risk additional radioactive contamination of the surrounding area, Viktor Kuchynskyi, deputy head of the Chernobyl nuclear power plant strategic planning department, said.

"With IAEA support, a team of international and Ukrainian scientists designed and implemented a project to safely decommission the cooling pond," Kuchynskyi said. As the water level decreased, comprehensive monitoring of radiation and environmental changes was carried out. Today, a "natural state" at the former cooling pond has been achieved and the radiation situation corresponds to the surrounding territory. In the process, unique experience in organising and implementing activities in radiation-contaminated territories has been gained and a large database of radiation and environmental observations built up. "The staff of the Chernobyl plant gained valuable new experience, which we are ready to share," he said.

The side event on IAEA Support to Environmental Remediation Projects at the 63rd General Conference (Image: H Boening/IAEA)

Plan from the start

Tanzania is home to the Mkuju River uranium project, which was discovered in 2007. Dennis Amos Mwalongo of the Tanzania Atomic Energy Commission (TAEC) described IAEA support to address the challenges the country was facing while developing its uranium mining and processing capability.

The Selous Game Reserve, within which Mkuju River is located, was in 1982 classified as a World Heritage Site and is one of the largest protected areas in Africa. This means Tanzania faces the challenges of regulating its first uranium mine in an environmentally sensitive area, with overlapping or conflicted mandates between government departments, Mwalongo said. This prompted the government of Tanzania to request an IAEA Uranium Production Site Appraisal Team (UPSAT) mission to address the challenges the country was facing while developing its uranium mining and processing capability. This 14-day in-depth mission, which took place in 2013, led to recognition of a potential problem with tailings storage and a revised flowsheet for mine operations.

"Planning for uranium mining and remediation and decommissioning should start well before actual mining starts," Mwalongo said. "The IAEA project helped us learn from the experience of others and so avoid any potential mistakes or higher than necessary costs."

In addition to the UPSAT mission, IAEA support for Tanzania has included an Integrated Regulatory Review Service mission, training courses on the uranium mining lifecycle, a School of Decommissioning and Environmental Remediation, and an introduction to other donors and partners, including the European Commission, the Canadian Nuclear Safety Commission, the US Department of Energy and the US Nuclear Regulatory Commission, Mwalongo said. The IAEA has also provided support for the procurement of equipment and user training, and investments in TAEC infrastructure and competencies. These processes have helped to build a high level of government trust in TAEC, measured in increased government investment and prioritisation of TAEC's future work, he said.

Sharing experience

Capacity building is one way in which the IAEA Technical Cooperation programme supports waste management, decommissioning and environmental remediation projects. The agency has over the past decade hosted numerous decommissioning and environmental remediation training courses at Argonne National Laboratory in the USA. Karen Smith, of the laboratory's Environmental Science Division, shared outcomes and lessons learned.

Decommissioning and environmental remediation projects are technically complex and highly interdisciplinary, and a diverse set of skills beyond critical science and engineering capacity is needed to ensure the ability to integrate information, develop strategies, make fully informed decisions, communicate about the project, and plan for and manage activities, Smith said. A lack of capacity can hamper implementation of projects that successfully reduce risk in the safest, most cost-effective, and technically appropriate manner possible.

Some 265 participants from 48 countries, including regulators, operators, technical staff, researchers, academics and consultants with a wide range of ages and levels of experience, have attended the training courses at Argonne, where the emphasis has been on providing practical skills relevant to overcoming barriers and constraints to successful implementation of decommissioning and environmental remediation projects. The courses aim to provide awareness-level training for project managers, planners, and other staff, covering topics including: project planning and decision-making; cost estimation; stakeholder involvement; regulation and policy; characterisation, sampling, and analysis; risk assessment and communication; waste management and material clearance; remediation technology selection; decontamination and dismantling; and site closure.

Experience has shown that capacity building is not a one-off event but should be a sustained process with follow-up training and engagements such as mentoring and fellowships, Smith said. "What proved to be a key to success is having a comprehensive curriculum that identifies the baseline level of knowledge required to succeed in a course and maps out the training materials in a structured way," she said.

ENVIRONET was created in 2009 to promote the exchange of experiences and good practices amongst environmental remediation project implementers, regulators and representatives from the technical and scientific communities, and to promote competence building in IAEA Member States.