Total dose to terrestrial critical group (adults)Ģ. Critical group doses from operations at Sellafield (µSv)Įxternal radiation from beach occupancy (marine)Įxternal radiation from beach occupancy (terrestrial) The emissions within the direct control of the company are dominated by the use of electricity and steam at the Sellafield site (>90%). Sellafield Ltd’s carbon footprint was reduced by 12% from 2018/19. This provides reassurance that they are part of the same general population and are within the range of activities that were considered in the health risk assessment. The distributions of caesium-137 and americium-241 activities for particles and larger objects recovered in 2019 were within the ranges previously observed. In particular, tritium discharges are dominated by operational activities and will virtually cease when reprocessing is completed. In considering future effluent discharge projections, the operational liquid and gaseous discharges are projected to reduce substantially as reprocessing activities are completed. The monitoring of the wells located around the site perimeter which detect any migration of radioactivity from the site have shown consistent results over the last five years, 2015 – 2019, indicating no significant levels of radioactivity have reached the site perimeter over this time period. Strontium-90, total alpha and total beta all remain similar to 2018 results. Groundwater investigations in 2019 have shown that the activity concentrations of tritium, technetium-99, The estimated doses for the marine (75 µSv) and terrestrial critical groups (11 µSv) are much lower than the dose constraint of 1000 µSv for exposure of members of the UK public to man-made controlled sources of radiation. The environmental concentrations of these radionuclides are also mostly due to historic rather than 2019 discharges. The most significant radionuclide contributing to dose received from the consumption of terrestrial foodstuffs is caesium-137 in sheep (0.88 µSv). The total dose to the terrestrial critical group (adults) was about 11 µSv. Inclusion of dose contributions to this group from inhalation, immersion, external radiation from beach occupancy and marine food consumption results in a dose of about 8 µSv.ĭoses due to direct radiation from plants on site were estimated as being up to 3.2 µSv to the most exposed members of the public who live nearby. The estimated dose in 2019 due to discharges to the atmosphere to members of the critical group who consume terrestrial foodstuffs was about 5 µSv. The most significant radionuclides contributing to this dose are Pu-alpha and americium-241 (32 µSv) - the environmental concentrations of these radionuclides are mostly due to historic discharges.
Taking into account doses due to beach occupancy and aerial pathways, the total dose to this group was about 75 µSv, lower than 2018. Doses due to discharges to sea from Sellafield to adult members of the critical group who consume fish and shellfish from the local area were about 37 microSieverts (µSv). The estimated doses in 2019 are summarised in the table below. Radioactive discharges (aerial and liquid) were well below the permitted limits and were generally lower than those in 2018. There were no instances in 2019 of non-compliance with the numerical limits of permits regulating discharges and disposals of radioactive wastes at Sellafield. The report provides a summary of the comprehensive data that are available for inspection by members of the public on the Public Registers maintained by the Environment Agency. It now includes information on beach monitoring, groundwater investigations, corporate carbon footprint and future effluent discharge projections. It provides detailed information on radioactive discharges and disposals, monitoring of the environment and radiological impact, and also includes information on non-radioactive discharges and disposals. This 2019 report has been produced by Sellafield Ltd and covers the Sellafield site in Cumbria.
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