NDA PhD Bursary Land Quality Nick Atherton, Sellafield Ltd Richard Short and Bill Thompson, Dounreay Site Restoration Ltd 29/09/15 1

NWDRF Land Quality Working Group Activities Sub-group of the Nuclear Industry Group for Land Quality and also reports to the NWDRF Nuclear Waste Research Forum –Share information on existing Research and Development (R&D) programmes –discussing common R&D needs, risks and opportunities –develop an action plan and where appropriate, take action to implement solutions to enable the improved delivery of the NDA mission and potentially aid the wider nuclear industry Membership includes: –NDA representative, AWE, NDA, Sellafield, MAGNOX, DSRL, RSRL, LLWR, RWM –Synergies exist with the Characterisation WG and Decommissioning WG 2

NWDRF Land Quality Working Group Activities Example projects directly managed by the WG –Improving the segregation of contaminated soils and building rubble during clean-up operations –Review of databases and archives of land characterisation and remediation techniques –Development of a methodology toolkit for sampling and interpretation of contaminated land data –Long term monitoring methodologies for contaminated land: A guide to good practice in data management and storage –Review of the US EPA Data Quality Objectives process –Industry Guidance Qualitative Risk Assessment for Land Contamination, including Radioactive Contamination –Real-time scanning and sorting of bulk soil and similar material –Dual beta-gamma probe for in-situ measurement of radioactively contaminated materials –Emerging Issues in Land Quality Management –Nuclear industry code of practice (NICoP) for routine water quality monitoring –Use of decommissioning rubble for void filling and landscaping on nuclear sites 3

PhD call decommissioning topics 1.Development of low cost technologies that can treat high volumes of groundwater with environmentally sensitive levels of Tc-99, Sr-90 and/or C Development of sensors (e.g. electrochemical, biological) that could be incorporated into a remote groundwater sensing network for the monitoring of common, problematic radionuclides. 3.Incorporating natural attenuation into design and management strategies for contaminated sites. 4.Diffusion & desorption of radionuclides (Cs & Sr) from concrete including characterisation and modelling of activated products in concrete, and mobilisation of these into the environment. 5.Assessment of stakeholder concerns pertaining to application of statistical approaches to decision making – specifically wrt systems applied to land quality issues. 6.Understanding the Chemotoxicity of radionuclides in waste scenarios found at nuclear licensed sites. 7.Expansion of performance envelope of latest generation analytical instruments to address RA contaminants found at NDA sites. 4

Development of low cost technologies that can treat high volumes of groundwater with environmentally sensitive levels of Tc-99, Sr-90 and/or C-14 Potential need to manage contaminated groundwater during site restoration challenge. –To support removal of contaminated soils –Protection of receptors –Longer term management of residual contamination Existing effluent treatment systems struggle to cope with completing ions and variability of effluent feed Not necessarily limited to ex-situ treatment Needs to be ‘relatively simple’ for deployment alongside site remediation Ongoing PhD is aligned to this topic. 5

Development of sensors (e.g. electrochemical, biological) that could be incorporated into a remote groundwater sensing network for the monitoring of common, problematic radionuclides Groundwater monitoring widely used and likely to be a long term requirement. –for example, Sellafield Ltd collect over 600 samples per year –With over 26 different analysis methods used Two areas of potential focus: –High frequency monitoring data to support decommissioning challenges (e.g. leak detection) –Long term remote monitoring (reassurance monitoring) Radionuclides include technetium-99, strontium-90 and carbon-14 Potential crossover with characterisation WG for sensors used in effluent treatment or waste retrieval systems 6

Incorporating natural attenuation into design and management strategies for contaminated sites Recognition that it may not be practicable or sustainable to remove all radioactive soils during site restoration. NDA strategy identifies the need for consideration of the applicability of Natural Attenuation, or ‘In-situ disposal’ Natural Attenuation needs to be scientifically underpinned to allow regulatory ‘buy-in’ Radionuclides include technetium-99, strontium-90, carbon-14, caesium-137, uranium and plutonium isotopes (and decay chains) Need to consider implications for safety case and/or post closure assessments Need to consider implications for long term liability management Ongoing PhD is aligned to this topic. 7

Diffusion & desorption of radionuclides (Cs & Sr) from concrete including characterisation and modelling of activated products in concrete, and mobilisation of these into the environment Many nuclear plants are of concrete construction and have deep foundations –Sites also contain a large number of below ground concrete structures (active drains etc) There are situations where the concrete has become contaminated (or is potentially contaminated) If these structures are left in-situ we need to understand: –How the contaminants are leached and released into the wider ground / groundwater environment –The long term risk that the release of contamination presents and the mechanisms involved, to complement existing understanding of contamination in soils We also need to find ways to characterise underground contaminated structures in-situ Potential crossover with the decommissioning and characterisation WGs 8

Assessment of stakeholder concerns pertaining to application of statistical approaches to decision making – specifically wrt systems applied to land quality issues Robust and rational decisions are required for the management of contaminated ground and groundwater issues on nuclear sites. –Identification of areas of concern –Management of contamination in-situ –De-licensing Some lack of stakeholder acceptance of statistical approaches (born from unfamiliarity and / or distrust) However: –Need to be able to quantify uncertainty in the decision and underpinning data –Need to be able to demonstrate safety performance General lack of capability within industry which generally relies upon direct comparisons with thresholds and lines of evidence Potential crossover with Characterisation WG 9

Understanding the Chemotoxicity of radionuclides in wastes scenarios found at nuclear licensed sites Ideally, radionuclides and hazardous materials should be assessed on a common risk management basis such that consistent assumptions are employed in assessments and consistent criteria used in the evaluation of risk. –However this is not commonly the case. Review of international approaches to the assessment of co- contamination of radioactive and chemotoxic substances –pragmatic way of maintaining consistency could be identified and trialled The assessment community is not always able to undertake the quality of assessment necessary to support regulatory and other decisions, due to a lack of supporting information and science. –This scientific underpinning could also support contaminated land assessment where material is left in-situ 10

Expansion of performance envelope of latest generation analytical instruments to address RA contaminants found at NDA sites Decommissioning and site restoration activities are often supported by intensive sampling and analysis campaigns Analytical methodologies have largely developed: –To support nuclear plant operations –To support environmental monitoring programmes –To support contamination exposure assessments The additional focus on sample analysis for decommissioning is already seen to cause ‘bottlenecks’ adding delays and extra costs to projects Potential focus areas: faster methods; less sample preparation; different media Also potential future skills gap in analytical chemistry and radioecology 11