Summary of Radioactivity in Food and the Environment 2004-2008

Northern Ireland Environment www.ni-environment.gov.uk Agency

ENVIRONMENTAGENCY FOOD STANDARDS AGENCY NORTHERNIRELANDENVIRONMENTAGENCY SCOTTISHENVIRONMENTPROTECTIONAGENCY

April 2010 This report was compiled by the Centre for Environment, Fisheries and Aquaculture Science on behalf of the Environment Agency, Food Standards Agency, Northern Ireland Environment Agency and the Scottish Environment Protection Agency.

Printed on paper made from a minimum 75% de-inked post-consumer waste.

Front cover picture: Oldbury Power Station. Published with the kind permission of the Environment Agency. © Crown Copyright, 2010

Requests for the reproduction of materials contained in this report and for other information should be addressed to: • in England and Wales, Radiological Monitoring and Assessment Team of the Environment Agency ([email protected]) or the Food Safety Contaminants Division of the Food Standards Agency ([email protected]) • in Scotland, the Radioactive Substances Unit of SEPA ([email protected]) and • in Northern Ireland, the Industrial Pollution and Radiochemical Inspectorate of NIEA ([email protected]) Contents Page

LIST OF FIGURES AND TABLES ...... 4

PREFACE ...... 5

INTRODUCTION ...... 6

1. Overview of total dose and environmental indicators near the UK’s nuclear sites ...... 8 1.1 Total dose assessment ...... 8 1.2 Environmental indicators close to and away from nuclear sites ...... 8 1.3 Doses to the public from diet away from nuclear sites ...... 11

2. Nuclear fuel production and reprocessing...... 12 2.1 Public’s exposure to radiation due to discharges of radioactive waste ...... 12 2.2 Sellafield, Cumbria ...... 14 2.2.1 Discharges of radioactive waste...... 14 2.2.2 Concentrations of radionuclides in food and the environment ...... 15 2.3 Capenhurst – Discharges of radioactive waste and concentrations of radionuclides in food and the environment ...... 16 2.4 Springfields – Discharges of radioactive waste and concentrations of radionuclides in food and the environment ...... 16 2.5 Summary ...... 18

3. Research establishments ...... 19 3.1 Public’s exposure to radiation due to discharges of radioactive waste...... 19 3.2 Dounreay – Discharges of radioactive waste and concentrations of radionuclides in food and the environment ...... 19 3.3 Harwell – Discharges of radioactive waste and concentrations of radionuclides in food and the environment ...... 20 3.4 Winfrith – Discharges of radioactive waste and concentrations of radionuclides in food and the environment ...... 21 3.5 Summary ...... 23

4. Nuclear power stations ...... 24 4.1 Public’s exposure to radiation due to discharges of radioactive waste...... 24 4.2 Discharges of radioactive waste from nuclear power stations...... 26 4.3 Concentrations of radionuclides in food and the environment ...... 29 4.4 Trawsfynydd – Discharges of radioactive waste and concentrations of radionuclides in the environment ...... 29 4.5 Summary ...... 31

5. Defence establishments ...... 32 5.1 Public’s exposure to radiation due to discharges of radioactive waste...... 32 5.2 Aldermaston, Devonport, Faslane and Coulport, and Rosyth – Discharges of radioactive waste...... 32 5.3 Defence establishments – Concentrations of radionuclides in food and the environment ...... 32 5.4 Summary ...... 35

6. Radiochemical production...... 36 6.1 Public’s exposure to radiation due to discharges of radioactive waste...... 36 6.2 Amersham – Discharges of radioactive waste and concentrations of radionuclides in food and the environment ...... 36 6.3 Cardiff – Discharges of radioactive waste and concentrations of radionuclides in food and the environment ...... 37 6.4 Summary...... 38

Summary and Conclusions ...... 40

3 List of Figures and Tables

Abbreviated Figure Title Number ...... Page

Total dose and environmental indicators UK doses from all sources 1 ...... 9 Indicator monitoring- technetium-99 in seaweed 2 ...... 10

Nuclear fuel production and reprocessing Doses from discharges – including wider communities 3 ...... 13 Sellafield – discharges of radioactive waste 4 ...... 14 Sellafield – monitoring from radioactive waste 5 ...... 15 Capenhurst – discharges and monitoring the environment 6 ...... 17 Springfields – discharges and monitoring the environment 7 ...... 18

Research establishments Doses from discharges 8 ...... 20 Dounreay – discharges and monitoring the environment 9 ...... 21 Harwell – discharges and monitoring the environment 10 ...... 22 Winfrith – discharges and monitoring the environment 11 ...... 23

Nuclear power stations Doses from discharges 12 ...... 25 Discharges of gaseous radioactive waste 13 ...... 27 Discharges of liquid radioactive waste 14 ...... 28 Monitoring – caesium-137 in marine sediments 15 ...... 30 Trawsfynydd – discharges and monitoring the environment 16 ...... 31

Defence Doses from discharges 17 ...... 33 Discharges of radioactive waste 18 ...... 34 Aldermaston – monitoring the environment 19 ...... 35

Radiochemical production Doses from discharges 20 ...... 37 Amersham – discharges and monitoring the environment 21 ...... 38 Cardiff – discharges and monitoring the environment 22 ...... 39

Abbreviated Table Title Number ...... Page

Total dose and environmental indicators UK general diet (Total Diet Study) 1 ...... 11

Nuclear fuel production and reprocessing Summary of trends for sector 2 ...... 18

Research establishments Summary of trends for sector 3 ...... 23

Nuclear power stations Summary of trends for sector 4 ...... 31

Defence Summary of trends for sector 5 ...... 35

Radiochemical production Summary of trends for sector 6 ...... 38

Summary and Conclusions Overall summary for nuclear sectors 7 ...... 40

4 Preface

Each year the Environment Agency, the Food Standards second largest total dose, with trends broadly reflecting a Agency, the Northern Ireland Environment Agency (NIEA) combination of changes in shellfish consumption rates, and and the Scottish Environment Protection Agency (SEPA) carry the concentrations of naturally-occurring radionuclides arising out a UK wide monitoring programme of radioactivity in food as a result of past discharges from the former phosphate and the environment around all 39 nuclear licensed sites and works at Whitehaven, in these shellfish. assess the public’s exposure to radiation. The cessation, decommissioning and defueling of the majority As partner agencies for environment and food protection, we of first generation nuclear power stations and reduction in publish our joint findings in an annual report, ‘Radioactivity reprocessing over the review period has clearly had a significant in Food and the Environment’ (RIFE) which brings together impact in reducing discharges and radiation doses to the the results of our radiological monitoring and provides an overall public. detailed assessment of radioactivity for the UK. The report is a compilation of the evaluations we make on the public’s For nuclear power station sites, the most significant trend over exposure to ionising radiation from authorised discharges, to the five-year period was an overall decline in gaseous and liquid show that exposure is within EU and UK limits. discharges. The most pronounced effects were at Chapelcross where discharges reduced significantly after the site stopped Building on the information derived from the last five RIFE generating electricity and at Hartlepool where all radionuclide reports (RIFE 10-14), we have prepared this review to give an discharges reduced whilst the site was closed down for repair overview of recent trends in data from 2004-2008. The report work. primarily focuses on trends associated with: Discharges of man-made radionuclides over the last two • radiation exposure (doses) to people living around nuclear decades have shown large and sustained reductions of the sites most important radionuclides. This is particularly true of the • disposals of radioactive waste (discharges) to air and nuclear fuel reprocessing sector where investment, for example water in new treatment plants, has had a significant effect. • radionuclide activity (concentrations) in samples collected Concentrations of radionuclides in food and the environment around nuclear sites have also declined over a similar time-frame. In addition, reductions in discharges and doses have occurred from older This report shows that for all 39 nuclear licensed sites, the Magnox power stations where the reactors have been shut overall amount of radiation the public was exposed to was down and ended electricity production. Therefore, in less than the UK and European limit of 1 millisievert (mSv, a comparison to earlier decades, some downward trends in measure of dose) per year, in each year over the five-year review environmental concentrations have become less significant in period. A key observation is that radionuclide concentrations the last five years. Where there have been radionuclide were very low at many sites, indeed so low they could not be fluctuations in recent years, this has been mostly at low detected with the sensitive methods used. In many cases concentrations in the environment, due to normal year to year there is a correlation between lower environmental variation. In some cases no clear trend is apparent and variation concentrations and reducing discharges to the environment, or ‘noise’ is a key feature of the monitoring data. showing that the efforts of regulators and the industry to progressively reduce discharges is having a beneficial effect. It is important to note that this is a summary of trend data over the last five years and is not a detailed technical report. At several nuclear sites, trends in total doses were dominated Anyone wanting to understand the in-depth background to by direct radiation (radiation arising from processes or the methodologies applied in the specific yearly assessments operations on the premises), with the largest total dose over should consult the relevant annual RIFE report. the five-year period reported at Dungeness. However, this direct radiation reduced after 2006 when the first generation http://www.food.gov.uk/science/surveillance/radiosurv/rife Magnox reactors at Dungeness A ceased power generation. Radiation exposure around Sellafield and Whitehaven was the

Preface 5 Introduction

This report provides a summary of the public’s exposure The UK Strategy for Radioactive (doses) to radiation to people, between 2004 and 2008, Discharges living around nuclear sites. It also gives more detail of time trends on discharges of radioactivity to the environment and The first UK Strategy for Radioactive Discharges was published concentrations of radionuclides in food and the environment in July 2002 and was updated in 2009. The Strategy was over the same time period for each of the nuclear industry prepared in response to commitments entered into by the UK sectors (e.g. nuclear fuel production and processing). The in 1998 as one of the OSPAR Contracting Parties. It gives a information in this report is taken from more detailed data framework for implementing the UK’s obligations in respect published in the annual Radioactivity in Food and the of the OSPAR Radioactive Substances Strategy. It presents a Environment (RIFE) reports. The RIFE reports give analytical strategic framework for discharge reductions by each nuclear results from independent monitoring carried out by the sector to help decision making by the nuclear industry and Environment Agency, SEPA, NIEA and the Food Standards regulators. There are some specific objectives in the Strategy, Agency. including achieving progressive and substantial reductions in radioactive discharges so that human doses should be kept The data are presented to indicate the overall trends in doses, as low as reasonably achievable. discharges and concentrations. These data allow a broad interpretation of the picture with time to whether the trends The UK Strategy for Radioactive Discharges presents Key are generally increasing, decreasing, largely staying the same Marine Environmental Indicators (KMEIs) at a number of or not showing a trend. locations around the coast of the UK. These help evaluate progress against the OSPAR targets and are included in the The report provides information that can be considered in its OSPAR Periodic Report Series. The KMEIs include seaweed at own right and in relation to a strategic view of the UK all the site locations. At some locations KMEIs include marine approach to managing the impact of radioactive discharges foods and seawater. All of the KMEI data are from monitoring over recent years. In particular it allows the radioactivity carried out by the Environment Agency, the Food Standards concentrations and public radiation doses to be considered Agency, SEPA and the NIEA. Selected KMEI data have been in relation to the 1998 Ministerial OSPAR agreement and the presented in this report. UK’s commitments under its national Radioactive Discharge Strategy. Westminster and Devolved Administrations have Statutory Guidance to the Environment also recently published guidance to the Environment Agency Agency and SEPA on Regulation of and SEPA on regulation of discharges so as to deliver the Discharges into the Environment requirements of the Strategy.

These more strategic elements are briefly described below. Statutory Guidance has been issued to the Environment Agency by the Department of Energy and Climate Change OSPAR (DECC) and the Welsh Assembly Government (WAG), and to SEPA by the Scottish Government. This offers additional The OSPAR Radioactive Substances Strategy was agreed by strategic high-level guidance on the key responsibilities of the Ministers in 1998. Its strategic objective is to prevent pollution Environment Agency for England and Wales and SEPA for of the OSPAR maritime area (marine environment of the Scotland. It provides guidance about how the environment North-East Atlantic) from ionising radiation through progressive agencies should implement the UK Strategy for Radioactive and substantial reductions in radioactive discharges, emissions Discharges and OSPAR commitments. The implementation and and losses. This has the ultimate aim of concentrations in the development of detailed guidance is the responsibility of the environment near background values for naturally-occurring regulator. radioactive substances and close to zero for artificial radioactive substances. This Strategy will be implemented so that by the The main focus of the Guidance from DECC and WAG to the year 2020 any releases of radioactive substances are low Environment Agency is the combination of Best Practicable enough so that any increase in the levels, above historic levels, Means (BPM) and Best Practicable Environmental Option in the marine environment from these discharges will be close (BPEO) as Best Available Techniques (BAT), as the main to zero. regulatory tool for controlling radioactive discharges. The Guidance also highlights the importance of the use of BAT in the optimisation of doses and the setting of discharge limits. In Scotland, Statutory Guidance to SEPA retains both BPM and BPEO approaches for regulation and the authorisation of

6 Introduction discharges which requires the optimisation of doses. SEPA takes account of the requirements of the UK Discharge Strategy and OSPAR during the authorisation process.

The Environment Agency has prepared “Regulatory Environmental Principles” (REPs) which underpin how it will implement the Statutory Guidance.

In Northern Ireland, the Department of the Environment does not provide statutory guidance but instead directs the Chief Inspector to ensure that when granting discharge authorisations they are consistent with the UK Waste Discharge Strategy. NIEA currently retains the BPM approach to regulation and authorisation of radioactive discharges.

Introduction 7 1. Overview of total dose and environmental indicators near the UK’s nuclear sites

This section considers the time trends of total dose1 summed over all sources at each site in the UK. It also considers Key Key points Marine Environmental Indicators (KMEIs) around the UK that • All total doses were less than the UK and have been used to evaluate the UK Strategy for Radioactive European dose limit Discharges. • Total dose and their trends were dominated by direct radiation at many sites 1.1 Total dose assessment • Total dose trend at Sellafield was influenced by changes in natural radioactivity from non- By 2008, the environment agencies and the Food Standards nuclear industry activity Agency had assessed total doses to the public at 24 nuclear • Total dose declined when electricity site locations. Trends of total dose over time (2004–2008) generation ended at several older Magnox around UK’snuclear sites are shown in Figure 1. The total doses power stations. from radiation at all sites were all less than the annual national • Trends in Key Marine Environmental Indicators (UK) and the European limit for members of the public of 1 mSv around the UK show decreasing per year, in each year over the five year period. An additional concentrations over the time period comparison can be made with doses from natural radioactivity. The UK average has been reported to be 2.2 mSv per year, with a range across the UK counties from 1.5 to 7.2 mSv very low and decreased over time. The largest contributor to per year. dose was low levels of external radiation above sediment at Cardiff. This was due to naturally-occurring radionuclides or Figure 1 shows the annual total dose was highest at Dungeness radioactive sources other than from the GE Healthcare site in in Kent, ranging between 0.28 and 0.63 mSv, over the five- Cardiff. The total dose at Sizewell in Suffolk declined at the year period. Total doses at Dungeness were dominated by direct end of 2006, following the closure of the Magnox reactors radiation, and following 2006, this dose declined due to the at Sizewell A. This was attributable in recent years to direct end of power generation from the first generation Magnox radiation. At Springfields in Lancashire the total dose decreased reactors. over time, although there was an increase in 2008 compared with 2007. The trend at this site was primarily due to variations The second highest annual total dose was at Sellafield and in gamma dose rates over sediment and improvements in the Whitehaven in Cumbria, ranging between 0.37 and 0.58 mSv methods used for dose assessments. over the five years. This trend broadly reflected a combination of changes in the amount of shellfish eaten and of naturally- Total doses at all the remaining locations in Figure 1 were low. occurring radionuclides from the non-nuclear industry in Any variations in total doses with time at these sites were these shellfish. The larger step changes (from 2004 to 2005 primarily due to changes in direct radiation or variations in and from 2007 to 2008) were due to variations in naturally- gamma dose rates from environmental variability. occurring radionuclides (mainly polonium-210 and lead-210). These radiologically significant concentrations are enhanced 1.2 Environmental indicators close to in fish and shellfish near Whitehaven because of past discharges and away from nuclear sites from a former phosphate plant. The changes in total dose in the intervening years (from 2005 to 2007) were mainly a Monitoring carried out by the Environment Agency, SEPA, NIEA result of changes in seafood consumption rates. The third and the Food Standards Agency includes data that are used highest exposure was at Amersham in Buckinghamshire, as part of the KMEIs. These are used to show how the UK is where annual total doses ranged from 0.22 and 0.24 mSv over meeting its OSPAR obligations. The KMEI include concentrations the five-year period. This trend remained broadly similar with of radionuclides in fish and shellfish, seaweed and seawater. time and was dominated by direct radiation. Seaweed data are available for a wide range of locations around the UK (as indicators for Sellafield-derived technetium- Other notable observations in total dose included increased 99) and are shown in Figure 2. The data show that exposure at Capenhurst in Cheshire. This was attributable in concentrations of all radionuclides have either reduced or are recent years to direct radiation. At Cardiff, the total doses were unchanged over the five-year period.

1 Total dose is an assessment that uses a defined method that takes account of all exposure pathways in combination e.g. radionuclides in food, the environment and direct radiation.

8 1. Overview of total dose and environmental indicators near the UK’s nuclear sites 0.75 A 0.75 2004 2005 2006 2007 2008 R 0.50

0.50 mSv 0.25 mSv 0.25 0 Dounreay

0 A 0.75 Hunterston B 0.75 Q 0.50 mSv 0.50 0.25 mSv 0.25 0 Torness 0.75 0 C Chapelcross 0.75 P 0.50 mSv 0.50 0.25 mSv 0.25 0 Hartlepool 0.75 0 Sellafield/Whitehaven D 0.75 O B 0.50 mSv 0.50 R 0.25

mSv 0 0.25 Amersham 0.75 E 0 Q Heysham 0.75 N 0.50 mSv 0.50 P C 0.25 mSv 0.25 0 Sizewell 0.75 0 F Springfields O N 0.50 0.75

M 0.75 mSv S 0.25 0.50 L M 0.50 mSv 0 0.25

mSv Bradwell K 0.25 0 Capenhurst 0 0.75 Harwell E L 0.50 S mSv 0.25 D F

0 I Wylfa J 0.75 K H 0.50 G mSv 0.25

0 Trawsfynydd 0.75 0.75 0.75 0.75 G J H

0.50 0.50 I 0.50 0.50 mSv mSv mSv mSv 0.25 0.25 0.25 0.25

0 0 0 0 Cardiff Berkeley & Oldbury Hinkley Dungeness Figure 1. Total radiation exposures around the UK’s nuclear sites due to radioactive waste discharges and direct radiation (2004-2008). (Exposures at Sellafield/Whitehaven receive a significant contribution to the dose from technologically enhanced naturally occurring radionuclides from previous non-nuclear industrial operations)

Footnote: Trends at Aldermaston and Burghfield, Devonport, Faslane and Coulport, Rosyth and Winfrith are excluded from the figure as, throughout the time period, the total doses from all sources were assessed to have been less than 0.005mSv. Total dose assessments have been updated from values reported in previous RIFE publications, to take into account revised direct radiation data.

1. Overview of total dose and environmental indicators near the UK’s nuclear sites 9 1000 Dounreay 5000 Chapelcross A J

(fresh) 500 -1

(fresh) 2500 -1

A Bq kg Bq kg

0 2004 2005 2006 2007 2008 0 2004 2005 2006 2007 2008

5000 Heysham

I 1000 Torness B

(fresh) 2500 -1 (fresh) Bq kg 500 -1 Bq kg

0 2004 2005 2006 2007 2008

5000 N Ireland H B 1000 Hartlepool

(fresh) 2500 C -1 Bq kg (fresh)

-1 500 Bq kg 0 2004 2005 2006 2007 2008 J

0 2004 2005 2006 2007 2008 H G C

5000 Sellafield G I (fresh)

-1 2500

Bq kg F

0 2004 2005 2006 2007 2008

5000 Wylfa F (fresh)

-1 2500

Bq kg D

0 2004 2005 2006 2007 2008

E 1000 Winfrith 1000 Bradwell E D (fresh) (fresh) -1 500 -1 500 Bq kg Bq kg

0 0 2004 2005 2006 2007 2008 2004 2005 2006 2007 2008

Figure 2. Technetium-99 concentrations in seaweed around the UK (2004-2008)

10 1. Overview of total dose and environmental indicators near the UK’s nuclear sites 1.3 Doses to the public from diet away from nuclear sites

The Food Standards Agency also has responsibility for food safety, and determines the doses from radionuclides in foods eaten around the UK. These data are presented in Table 1. This gives an indication of the range of doses to the public from foods between 2005 and 2008.

Table 1. Ranges of estimated dose from radionuclides in diet between 2005-2008#

Country Mean exposure mSv/y

Man-made radionuclides Naturally-occurring radionuclides All radionuclides

England 0.001 - 0.002 0.035 - 0.28 0.036 - 0.28 Wales 0.001 0.029 - 0.098 0.030 - 0.099 Northern Ireland 0.001 - 0.002 0.039 - 0.075 0.04 - 0.077 Scotland 0.002 - 0.003 0.054 - 0.16 0.057 - 0.17 UK 0.001 - 0.002 0.039 - 0.24 0.040 - 0.24

# Note : no equivalent dose data by region was reported in 2004 (RIFE 10)

1. Overview of total dose and environmental indicators near the UK’s nuclear sites 11 2. Nuclear fuel production and reprocessing

This section looks at the trends over the five years (2004-2008) from the UK’s nuclear fuel production and reprocessing sites. Key points The time trends show the public’s exposure, discharges of • All doses were significantly less than the dose radioactive waste and concentrations of radionuclides in food limit for members of the public of 1 mSv per and the environment. The public’s exposure* (dose) from year radioactive waste discharges is assessed using radionuclide • Highest annual dose (from artificial concentrations and gamma dose rates in the environment. radionuclides) was 0.24 mSv at Sellafield The public’s exposure from naturally-occurring radionuclides • Overall trend was a reduction in gaseous and is also considered near Sellafield. liquid discharges, with all authorised discharges below authorised limits There are four sites in the UK involved with production and • Doses from historic non-nuclear industry reprocessing of nuclear fuel. Capenhurst, near Ellesmere Port activity (naturally-occurring radionuclides) in Cheshire has two licensed nuclear sites; one produces were significant near Sellafield enriched uranium and the other is currently being decommissioned. The third site is at Springfields, near Preston, where fuel for nuclear power stations is made. The fourth site is Sellafield in West Cumbria where irradiated fuel from Figure 3 also shows the trend of doses to people who ate nuclear power stations is reprocessed. seafood near Sellafield resulting from the historic discharges of naturally-occurring radionuclides from the former phosphate 2.1 Public’s exposure to radiation due works (non-nuclear industry) at Whitehaven (shown in green). to discharges of radioactive The data show that the doses from naturally-occurring waste radionuclides were significantly larger than for artificial radionuclides. The increases in dose for naturally-occurring radionuclides in recent years were due to changes to both Trends over time (2004-2008) for the exposure to radiation concentrations (polonium-210) in sea food and consumption due to waste discharges from the UK’s nuclear fuel production rates (of fish and shellfish). and reprocessing sites are for those groups most exposed to radiation and shown in Figure 3. Exposure of communities associated with fisheries in other parts of the Irish Sea was also assessed. These included Whitehaven, At all locations, the doses from radioactive waste discharges Dumfries and Galloway, Morecambe Bay, Fleetwood, Northern were significantly below the UK and European limit for Ireland, North Wales and the Isle of Man. The assessments members of the public of 1 mSv per year. show that exposures in these areas were lower than to people local to Sellafield. This was due to the lower concentrations The highest annual dose (from artificial radionuclides) was 0.24 and dose rates further away from Sellafield. There were small mSv in 2008 near Sellafield. Over the five years these Sellafield changes in the reported doses in each area over the time period. annual doses ranged from 0.22 to 0.24 mSv. This was less than These were caused by variations in gamma dose rates over a quarter of the dose limit. This was determined in people who sediment, new information on people’s eating habits and ate seafood, and was mostly due to the accumulation of fluctuations in radionuclide concentrations (mainly americium- radionuclides including caesium-137, plutonium isotopes and 241 in some shellfish). americium-241 in seafood and the environment. These doses were attributable to historic liquid discharges from Sellafield At Dumfries and Galloway, the people who consumed seafood which were at their highest during the 1970s and 80s. received the highest annual dose in Scotland over the five year- Between 2004 and 2007, habit surveys indicated an increase period. This was the group most exposed to the effects of in the amount of fish and shellfish eaten, which led to a Sellafield discharges. The annual doses ranged between 0.031 slight rise in doses during this time. In 2008 consumption went and 0.060 mSv over the five-year period. The increase in down again leading to a reduction in doses, together with a dose in 2007 around Dumfries and Galloway was attributed reduction in dose from artificial radionuclides. to an increase in the amount of shellfish eaten, identified from

* The monitoring results are interpreted in terms of radiation exposures of the public, commonly termed ‘doses’. These people are a group, who generally eat large quantities of locally grown food (high rate consumers) or who spend long periods of time in the locations being assessed. This dose, referred to in Sections 2-6, is an exposure that uses a different assessment method to that of total dose in Section 1.

12 2. Nuclear fuel production and reprocessing 0.20

0.10 mSv

0 Dumfries and Galloway

0.10 0.10 A

0.05 mSv

mSv 0.05 A 0 B Whitehaven 0 Northern Ireland 0.10 0.75 B B 0.5 0.05 mSv 0.10 mSv 0.25

0.05 0

mSv 0 Sellafield (aquatic) Sellafield (gaseous)

0 Isle of Man 0.10 D

0.05 D mSv 0.10 C 0 Morecambe Bay 0.05

mSv C

0 Fleetwood 0.20 E E

0.10 mSv 0.10 F

0 0.05 Springfields mSv

0 Capenhurst

Naturally occurring radionuclides 0.10 F 2004 2005 2006 2007 2008 0.05 Artificial radionuclides mSv 2004 2005 2006 2007 2008 20 km 0 North Wales Figure 3. Individual radiation exposures to most exposed groups from artificial radionuclides, Irish Sea (2004-2008) (includes exposures from naturally-occurring radionuclides near Whitehaven)

new habits survey information. For all assessments of exposure The next group most affected by artificial radionuclide of the fishing communities, there would also have been discharges was in the Ribble Estuary near the Springfields site. fluctuations in concentrations due to normal sampling For those people living on houseboats in the Ribble Estuary, variability. Whilst there were changes between years in the there was an apparent increase in annual dose, which ranged concentrations of some radionuclides in seafood, their effect between 0.037 and 0.130 mSv over the five-year period. was relatively minor. However, the trend over time included improvements in the methods used for dose assessments. The increase in doses from The annual doses received by people at Sellafield, who were 2006 was due to updated information and additional exposed to gaseous discharges from the site ranged between measurements concerning the exact location of houseboats. 0.023 and 0.036 mSv over the five-year period. The dose was The further increase in 2008 was due to a combination of from inhaling gases, from radiation emitted from the gas increased gamma dose rates and the time spent on the and from eating food grown on land around the site. Before houseboats. 2008, this trend was generally declining because of the permanent shut down of Calder Hall power station on the At Capenhurst, children playing in and around Rivacre Brook Sellafield site which ended gaseous discharges of argon-41 received the highest annual dose. This ranged between 0.007 and sulphur-35. In 2008, the assessment method changed and 0.010 mSv over the five-year period. The doses were slightly to include cobalt-60 results (which were at the limits estimated using gamma dose rates, assuming children spent of analytical detection) which increased the dose over previous time on the banks of the brook and swallowed some water years. and sediment. The changes in dose over time were due to variations in gamma dose rates over sediment.

2. Nuclear fuel production and reprocessing 13 2.2 Sellafield, Cumbria Gaseous discharges from Calder Hall dropped significantly from then on. Since 2004, the overall trend was a reduction of 2.2.1 Discharges of radioactive waste gaseous and liquid discharges with time. In 2008, a revised gaseous authorisation limit was introduced for antimony-125 Authorised discharges of gaseous and liquid waste are released to reflect increased discharges of this radionuclide as a result into the atmosphere and into the Irish Sea, from a wide of reprocessing Magnox spent fuel. All liquid discharges variety of facilities and sources. Figure 4 shows the trends of followed a pattern of overall reduction, technetium-99 for discharges over time (2004–2008) for a number of the example continued to significantly decline over the five-year authorised radionuclides. period. Other reductions in liquid discharges in recent years were due to a decrease in the rate of spent fuel reprocessing The Sellafield site included a Magnox power station, at Calder operations. Hall. In 2003 the power station stopped generating electricity.

Liquid discharges Gaseous discharges

1.0 Carbon-14 20 Carbon-14

0.5 10 TBq TBq

0 0 2004 2005 2006 2007 2008 2004 2005 2006 2007 2008 0.00010 Strontium-90 1.0 Cobalt-60 TBq

0.00005 0.5 TBq

0 0 2004 2005 2006 2007 2008 2004 2005 2006 2007 2008 0.010 Ruthenium-106 20 Technetium-99

0.005 TBq 10 TBq

0 2004 2005 2006 2007 2008 0.010 0 2004 2005 2006 2007 2008 Antimony-125

20 Caesium-137

0.005 TBq

10 TBq

0 Sellafield 2004 2005 2006 2007 2008 0.10 Iodine-129 0 2004 2005 2006 2007 2008

0.10 Americium-241 0.05 TBq

0.05 TBq 0 2004 2005 2006 2007 2008 0.00010 Plutonium-alpha 0 2004 2005 2006 2007 2008

1.0 0.00005

Plutonium-239+240 TBq

0.5 0 TBq 2004 2005 2006 2007 2008 0.0010 Caesium-137

0 2004 2005 2006 2007 2008

0.0005 TBq

15 km 0 2004 2005 2006 2007 2008

Figure 4. Authorised discharges of gaseous and liquid wastes, Sellafield (2004-2008)

14 2. Nuclear fuel production and reprocessing 2.2.2 Concentrations of radionuclides 2008. All radionuclide concentrations in the environment in food and the environment from gaseous discharges were very low. Over the five-year period, concentrations of caesium-137, carbon-14 and The food and environment monitoring programmes around strontium-90 in milk were relatively constant. Sellafield are the most extensive in the UK; this includes monitoring for the effects from Sellafield in other parts of the Concentrations of radionuclides in seafood generally continued Irish Sea. The monitoring reflects the range and concentrations to reflect changes in liquid discharges over the five years. The of radionuclides that have been discharged from Sellafield over majority of trends for carbon-14 and cobalt-60 concentrations a considerable number of years. showed large decreases directly associated with a fall in discharges since 2004. Similarly, technetium-99 concentrations Figure 5 shows the trends of radionuclide concentrations in in shellfish declined significantly. Between 2004 and 2008, food (winkles, lobsters, plaice and milk) and the environment concentrations of caesium-137 in seafood were relatively (seawater and sediment) near Sellafield between 2004 and constant, with any changes attributable to natural variation

12 Caesium-137 (seafood)

8 (fresh) Lobsters -1 Winkles 1.0 Plaice Caesium-137 (seawater) at St Bees

Bq kg 4 0.8

0.6 -1 0 2004 2005 2006 2007 2008 Bq l 0.4

0.2 4000 Technetium-99 (seafood) Lobsters 0 Winkles x 10 3000 Plaice x 100 1986 2000 2005 1995 1990 (fresh) -1 2000 25 Activity (milk) Bq kg

1000 20

15 -1 0

2004 2005 2006 2007 2008 Bq l 10

30 Cobalt-60 (seafood) 5 Cs-137 x100 C-14 Lobsters x 10 Sr-90 x100 Winkles 0 Plaice x 100 2004 2005 2006 2007 2008 20 (fresh) -1

10 Bq kg

0 2004 2005 2006 2007 2008 St Bees

500 Carbon-14 (seafood) Lobsters 400 Winkles Plaice

300

(fresh) Sellafield -1 200 2000 Bq kg 100 Activity (sediment) at Ravenglass Am-241 0 Pu-239+240 2004 2005 2006 2007 2008 Cs-137 Co-60 x 10 (dry) Ravenglass -1 1000 60 Plutonium-239+240 (seafood) Bq kg

(fresh) 0

-1 Lobsters x 100 2004 2005 2006 2007 2008 Winkles Plaice x 100 20 Bq kg

0 2004 2005 2006 2007 2008

80 Americium-241 (seafood)

Lobsters x 10 Winkles Plaice x 10 (fresh) 40 -1 Bq kg

0 2004 2005 2006 2007 2008

15 km

Figure 5. Monitoring of the environment from discharges of radioactive wastes, Sellafield (2004-2008)

2. Nuclear fuel production and reprocessing 15 in the samples taken from the environment. Caesium-137 Concentrations of technetium-99 in sediment (Rivacre Brook) concentrations in seafood may be affected by the release of from liquid discharges were detectable close to the discharge this radionuclide from seabed and estuary sediment. Over the point. The increase in 2007 was probably due to the discharge last five years, concentrations of plutonium-239+240 and occurring at the same time as environmental sampling. americium-241 in seafood were relatively constant, with a few Concentrations of caesium-137 and americium-241 in slightly elevated concentrations in shellfish in the most recent sediments at Rock Ferry and New Brighton on the Irish Sea years. coast were from past discharges from Sellafield carried into the area by tides and currents. The concentrations were Figure 5 also shows the trends in concentrations in sediment generally similar over the five years and any fluctuations were from Ravenglass (five years) and caesium-137 in seawater most likely due to normal changes in the environment. (1986-2008) at St Bees. For caesium-137 in seawater, the figure shows (as the rate of decrease is slower, relative to the 2.4 Springfields – Discharges of reduction rate of discharges, over the longer period) that the radioactive waste and current sources are liquid discharges from the site and the concentrations of radionuclides in release of caesium from sediments (from earlier discharges in earlier decades) into the water column. The concentrations food and the environment of most radionuclides in sediments have decreased over the past two decades, responding to decreases in discharges. The main radioactive constituent of gaseous discharges from Over the five-year period, sediment concentrations of cobalt- Springfields is uranium with small amounts of other 60 at Ravenglass followed the changes in discharge levels, with radionuclides from research and development facilities. some evidence of a lag time between discharge and sediment Authorised discharges of liquid waste (including alpha and beta concentrations. emitting radionuclides, technetium-99, thorium-230, thorium- 232, neptunium-237, uranium and other transuranic Over the last five years, there has been some variability in the radionuclides) are made from the Springfields site to the concentrations of several radionuclides in sediments at Ribble Estuary by two pipelines. The largest discharge for a Ravenglass. There is even a suggestion of progressive increases number of years was of short half-life beta emitting in the concentrations in sediments (peaking over the period radionuclides (mainly thorium-234). 2004–2006). This was followed by a decline to the lowest levels in 2008. This trend in concentrations was most likely due to Figure 7 shows the trends of these discharges over time (2004 disturbing, moving and resettling of fine-grained sediments – 2008) for a number of the authorised radionuclides. containing higher activity concentrations. For americium-241, increases in concentrations could be due to gradual in-growth The most significant change in the discharge trends was the from radioactive decay of plutonium-241. This is already step reduction of short half-life beta emitting radionuclides present in the environment from past site discharges. in liquid discharges, mostly thorium-234. The reduction was because the Uranium Ore Concentrate purification process 2.3 Capenhurst – Discharges of ended in 2006. Liquid discharges of uranium radionuclides radioactive waste and steadily decreased over time, whilst other discharges were concentrations of radionuclides in relatively constant. food and the environment Figure 7 also shows the trends of radionuclide concentrations in food (cabbage, shrimps, flounders and salmon) and the Uranium is main gaseous radionuclide discharged from the environment (sediment) near Springfields. two licensed nuclear sites at Capenhurst. Liquid waste discharges to the Rivacre Brook are authorised for tritium, The concentrations of radionuclides from gaseous discharges uranium and daughters, technetium-99 and non uranium were very low. Over the five-year period, concentrations of alpha (mainly neptunium-237). uranium were found in soil around the site, but the isotopic ratio showed they were naturally-occurring. Total uranium in Figure 6 shows the trends of these discharges over time cabbage samples was also detected during the period (no data (2004–2008) for a number of the authorised radionuclides. in 2006), but the apparent peak in 2007 was very low and significantly less, when compared to concentrations in slightly The overall trend was a reduction in gaseous and liquid elevated soil samples. discharges. Most of the reductions were attributed to progress in decommissioning some of the older plant and equipment. Concentrations of technetium-99 and caesium-137 were present in flounder, shrimps and salmon around Springfields. Figure 6 also provides selected monitoring trends to assess These were due to past liquid discharges from Sellafield, the impact on the surrounding environment. The carried from the waters off West Cumbria into the Ribble concentrations of technetium-99 in grass were relatively low Estuary by sea currents and adsorbed on fine-grained mud. during the five-year period. Concentrations of Uranium The change in concentrations was due to natural changes in radionuclides in food and the environment were very low. the environment.

16 2. Nuclear fuel production and reprocessing 0.000010 Uranium (gaseous) 0.0004 Uranium (liquid)

0.000005 TBq 0.0002 TBq

6 Activity (sediment at New Brighton)

0 0 2004 2005 2006 2007 2008 2004 2005 2006 2007 2008 (dry)

-1 3 0.0006 Uranium daughters (liquid) Bq kg Caesium-137 Americium-241

0 TBq 2004 2005 2006 2007 2008 0.0003

New Brighton

0 2004 2005 2006 2007 2008

0.00004 Non-uranic alpha (liquid) TBq 0.00002

Rock Ferry

150 Activity (sediment) at 0 Rock Ferry 2004 2005 2006 2007 2008

0.0004 100 Technetium-99 (liquid) (dry) -1

Bq kg Rivacre Brook TBq Caesium-137 0.0002 Americium-241

0 2004 2005 2006 2007 2008

Capenhurst site 0 1500 Technetium-99 (sediment) at Rivacre Brook 2004 2005 2006 2007 2008

3 1000 Technetium-99 in grass at Capenhurst (dry) -1

500 Bq kg (fresh)

-1 1.5

0 Bq kg 2004 2005 2006 2007 2008

0 2004 2005 2006 2007 2008

5 km

Figure 6. Discharges of gaseous and liquid radioactive wastes and monitoring of the environment, Capenhurst (2004-2008)

The trends over the five-year period of concentrations in sediments from liquid discharges are shown in Figure 7. The concentration trends were dominated by the reduction of thorium-234 in liquid discharges. Concentrations of caesium- 137 and americium-241 in marine life, which have shown a more gradual downward trend, were due to discharges from Sellafield, which have themselves reduced during this period.

2. Nuclear fuel production and reprocessing 17 120 Beta (liquid) 0.01 Neptunium-237 (liquid) 0.01 Uranium (gaseous) 1 Technetium-99 (liquid)

0.0075 0.0075 80

TBq 0.005 0.005

TBq 0.5 TBq TBq 40 0.0025 0.0025

0 0 0 0 2004 2005 2006 2007 2008 2004 2005 2006 2007 2008 2004 2005 2006 2007 2008 2004 2005 2006 2007 2008

0.1 Uranium (liquid) 0.01 Other transuranic nuclides (liquid) Springfields site 0.2 Total Uranium (cabbage) 0.0075

0.05 0.005 TBq TBq (fresh)

-1 0.1 0.0025 Bq kg

0 0 2004 2005 2006 2007 2008 2004 2005 2006 2007 2008 0 2004 2005 2006 2007 2008

0.50 Caesium-137 (salmon) Outfall

(fresh) 0.25 Lower -1 Penwortham Bq kg 160000 Activity (sediment) at outfall Park

0 Thorium-234 2004 2005 2006 2007 2008 120000 Caesium-137 x 100 Ribble Estuary Americium-241 x 100 (dry) -1 10 Caesium-137 (flounder) 80000 Bq kg 7.5 40000

(fresh) 5 -1 0 2004 2005 2006 2007 2008

Bq kg 2.5 Becconsall Activity (sediment) at 0 20000 Lower Penwortham Park 2004 2005 2006 2007 2008

15000 Thorium-234 1.6 Technetium-99 (shrimps) Caesium-137 x 10

(dry) Americium-241 x 10 -1 10000 1.2 Bq kg (fresh)

-1 0.8 5000

Bq kg 0 0.4 2004 2005 2006 2007 2008

0 2004 2005 2006 2007 2008 12000 Activity (sediment at Becconsall)

Thorium-234 Caesium-137 x 10 8000 Americium-241 x 10 (dry) -1

4000 Bq kg

0 2004 2005 2006 2007 2008 1 km

Figure 7. Discharges of gaseous and liquid radioactive wastes and monitoring of the environment, Springfields (2004-2008)

2.5 Summary

The information presented in Table 2 gives an overview of trends associated with doses, discharges and environmental concentrations described in Section 2.

Table 2. Summary of trend data for nuclear fuel production and reprocessing sector (2004-2008)*

Trend data Downwards No change Upwards Overall Gaseous discharges 711Majority downward trend Liquid discharges 13 02Majority downward trend Overall discharges 20 13Majority downward trend Environmental concentrations 513No overall direction Food concentrations 704Majority downward trend Food and the environment overall 12 17Majority downward trend All doses were below the dose limit

* Taken from the number of trend graphs for this sector presented in this report. This is a visual evaluation only.

18 2. Nuclear fuel production and reprocessing 3. Research establishments

This section looks at the trends over the five years (2004-2008) from the UK’s research establishments that hold Nuclear Site Key points Licences. The time trends show the public’sexposure, discharges • All doses were less than the dose limit for of radioactive waste and concentrations of radionuclides in members of the public of 1 mSv per year food and the environment. The public’s exposure* (dose) • Highest annual dose (from artificial from radioactive waste discharges is assessed using radionuclide radionuclides) was 0.047 mSv at Dounreay concentrations and gamma dose rates in the environment. • All authorised discharges were well below the authorised limits There are seven sites associated with research reactors that • Overall, gaseous and liquid discharges were are currently authorised to discharge radioactive waste in the low UK. The main sites are Dounreay in Highland, Harwell in • Concentrations in the marine and terrestrial Oxfordshire and Winfrith in Dorset. Other smaller research sites environment and food continued to be very include Culham (Oxfordshire), the Imperial College Reactor low Centre (Berkshire), the Scottish Universities’ Environmental Research Centre (Lanarkshire), and Windscale (Cumbria) which is on the Sellafield site. relatively small increase in dose was attributed to a general 3.1 Public’s exposure to radiation due increase in gamma dose rates. to discharges of radioactive waste At Harwell, the group of people most affected by radioactive waste discharges were anglers on the River Thames, with annual doses from less than 0.005 to 0.013 mSv over the five- The public’s exposure to radiation around all research year period. This change in dose with time was mainly due establishment sites was assessed. All doses were much less to a decrease in gamma dose rates (in 2006) and revised than the UK and European limit of 1 mSv per year for members occupancy rates on the river bank (in 2007). of the public. At Winfrith (and all the other smaller sites), all assessed doses Figure 8 shows the trends over the five years between 2004 were well below 0.005 mSv, which is less than 0.5 per cent and 2008 of the public’sexposure to radiation due to the effects of the dose limit for members of the public. of gaseous and liquid waste discharges at the main research sites. 3.2 Dounreay – Discharges of radioactive waste and The figure shows the highest annual dose was at Dounreay concentrations of radionuclides in from consuming food produced on land around the site. This ranged between 0.008 and 0.047 mSv over the five-year food and the environment period. The sudden increase in dose in 2005 (and subsequent dose thereafter) was due to dose estimates being more Gaseous and liquid discharges are released into the atmosphere conservative. They were more conservative because higher and into the sea (Pentland Firth). analytical limits of detection were used in the assessments. Figure 9 shows the trends of discharges over time (2004–2008) The annual dose from seafood consumption and external for a number of the authorised radionuclides. exposure over local beaches at Dounreay ranged from less than 0.005 to 0.010 mSv over the five year-period. Between 2004 The levels of several of the radionuclides from gaseous and and 2007, the variations in dose were mostly likely due to liquid discharges appeared to peak in 2005, but then reduced normal changes in the environment. In 2008 however, a in following years.

3. Research establishments 19 2004 2005 2006 2007 2008

0.05 A A v 0.025 mS

0 Dounreay (aquatic)

0.05 A

Sv 0.025 m

0 Dounreay (terrestrial)

0.05 B

0.025 mSv

0 Harwell (aquatic)

0.05 C

0.025 mSv

0 Winfrith (aquatic)

Figure 8. Individual radiation exposures to most exposed groups from artificial radionuclides, Dounreay, Harwell and Winfrith (2004-2008)

Figure 9 also provides selected monitoring trends to assess 3.3 Harwell – Discharges of the impact on the surrounding environment. The majority of radioactive waste and measurements of radionuclide concentrations in food and the concentrations of radionuclides in environment were at or below the analytical limits of detection, which made it difficult to produce valuable trend monitoring food and the environment data that may correspond to discharge data. Nevertheless, concentrations of technetium-99 from Sellafield found in Gaseous and liquid releases from Harwell are discharged into seaweed taken from Sandside Bay, Kinlochbervie and Burwick the atmosphere and to the River Thames at Sutton Courtenay Pier showed an overall decline over the period. Variations were and to the Lydebank Brook north of the site. most likely due to the complexity of how radionuclides move around in the Irish Sea, with technetium-99 being dispersed Figure 10 shows trends of discharges over time (2004–2008) in varying amounts before arriving at distant locations. for a number of the authorised radionuclides. Concentrations of caesium-137 in sediments at Sandside Bay, Rennibister and Oigins Geo were likely to include a contribution The gaseous discharges were low and generally similar over from Sellafield discharges. The concentrations were generally the five-year period. There was an overall reduction in liquid unchanged over the five-year period, with any fluctuations discharges, particularly for cobalt-60, and, to a lesser extent, most likely due to normal variations in the environment. for caesium-137.

20 3. Research establishments 0.001 Beta (gaseous)

1 Strontium-90 (liquid)

0.0005 TBq

0.5 TBq

0 2004 2005 2006 2007 2008

0.0001 0 Strontium-90 (gaseous) 2004 2005 2006 2007 2008

0.1 Caesium-137 (liquid) 0.00005 TBq

0.05 TBq 0 2004 2005 2006 2007 2008

0.0001 0 Caesium-137 (gaseous) 2004 2005 2006 2007 2008

0.001 Alpha (liquid) 0.00005 TBq

0.0005 0 TBq 2004 2005 2006 2007 2008

0.001 Iodine-129 (gaseous)

0 2004 2005 2006 2007 2008

0.0005 TBq

0 2004 2005 2006 2007 2008

0.0001 Alpha (gaseous) Rennibister

300 Technetium-99 (seaweed) 0.00005 TBq Kinlochbervie Orkney Islands Sandside Bay Burwick Pier (fresh)

-1 150 0 2004 2005 2006 2007 2008 Bq kg

0 2004 2005 2006 2007 2008 Caesium-137 (sediment) 20 Oigins Geo Sandside Bay Rennibister Burwick Pier (dry)

-1 10 Bq kg

0 2004 2005 2006 2007 2008 Oigins Geo

Sandside Bay Dounreay site Kinlochbervie 10 km Wick Figure 9. Discharges of gaseous and liquid radioactive wastes and monitoring of the environment, Dounreay (2004-2008)

Figure 10 also provides monitoring trends from three locations 3.4 Winfrith – Discharges of to assess the impact on the surrounding environment. radioactive waste and Concentrations of caesium-137 in sediments from the Harwell concentrations of radionuclides in outfall, Appleford and Lydebank Brook were generally declining due to reduced liquid caesium-137 discharges. As expected, food and the environment the biggest difference in concentrations was observed near the discharge point. Discharges from Harwell to the Thames Gaseous emissions from Winfrith are discharged into the are not continuous but occur in batches when tanks are atmosphere, and liquids to deep water in Weymouth Bay and emptied. The slight increase in 2007 was probably due to the to the River Frome. discharge occurring at the same time as environmental sampling. Figure 11 shows the trends of discharges over time (2004– 2008) for a number of the authorised radionuclides.

Gaseous discharges of tritium peaked in 2006 and this coincided with a revised authorisation to increase tritium discharges from the site, for the processing of wastes. Other gaseous and liquid discharges remained at low rates over the period.

3. Research establishments 21 0.00000010 Cobalt-60 (liquid) Alpha (gaseous) 0.00001 TBq

0.00000005 TBq 0.000005

0 2004 2005 2006 2007 2008 0 2004 2005 2006 2007 2008 0.00001 Beta (gaseous) 0.0001 Alpha (liquid) TBq

0.000005 TBq River Thames 0.00005

0 2004 2005 2006 2007 2008 0 2004 2005 2006 2007 2008 1 Tritium (gaseous) 0.0001 Caesium-137 (liquid)

0.5 TBq 0.00005 TBq

0 2004 2005 2006 2007 2008 0 20 Caesium-137 (sediment) at outfall 2004 2005 2006 2007 2008

15 (dry)

-1 10 1 Radon-222 (gaseous) Bq kg 5

0 2004 2005 2006 2007 2008 0.5 TBq

Outfall 0 2004 2005 2006 2007 2008

Appleford

20 Caesium-137 (sediment) at Appleford

15 (dry)

-1 10 Bq kg 5

0 20 Caesium-137 (sediment) at Lydebank Brook 2004 2005 2006 2007 2008

15 Lydebank (dry) -1 10 Brook Harwell site Bq kg 5

0 2004 2005 2006 2007 2008 5km

Figure 10. Discharges of gaseous and liquid radioactive wastes and monitoring of the environment, Harwell (2004-2008)

Figure 11 also provides radionuclide concentrations from four Plutonium radionuclides and americium-241 concentrations locations, to assess the impact on the surrounding environment. in seafood from the Lulworth Ledges, Lulworth Cove and Poole Concentrations of tritium in a stream north of the site showed Bay were very low over the five-year period. Over the last five enhanced levels that slightly increased following the revision years, there has been some variability in the concentrations of the authorisation in 2006. These concentrations were still of these radionuclides in some foods, which may indicate that relatively low and were less than 10 per cent of the World these concentrations had followed the trend in alpha liquid Health Organisation’s screening levels for drinking water. discharges.

22 3. Research establishments 5 km 30 Tritium in freshwater (north of site)

20 -1 Bq l 20 Tritium (gaseous) River Frome 10

0 2004 2005 2006 2007 2008 10 TBq

Winfrith 0 site 2004 2005 2006 2007 2008 Poole Bay

0.01 Carbon-14 (gaseous)

0.0075

0.005 Lulworth Ledges Arish

TBq Mell 0.0025

0 Lulworth 2004 2005 2006 2007 2008 Banks

0.01 Americium-241 (seafood)

Poole Bay whelks Lulworth Banks crabs Lulworth Ledges scallops

(fresh) 0.005 -1 0.001 Alpha (liquid) Bq kg 0.00075

0 2004 2005 2006 2007 2008 TBq 0.0005

0.01 Plutonium-239+240 (seafood) 0.00025

0 Poole Bay whelks 2004 2005 2006 2007 2008 Lulworth Banks crabs Lulworth Ledges scallops 0.005 100

(fresh) Tritium (liquid) -1

75 Bq kg

50 0 TBq 2004 2005 2006 2007 2008 25

0 2004 2005 2006 2007 2008

Figure 11. Discharges of gaseous and liquid radioactive wastes and monitoring of the environment, Winfrith (2004-2008)

3.5 Summary

The information presented in Table 3 gives an overview of trends associated with doses, discharges and environmental concentrations described in Section 3.

Table 3. Summary of trend data for research sector (2004-2008)*

Trend data Downwards No change Upwards Overall Gaseous discharges 173No overall direction Liquid discharges 620Majority downward trend Overall discharges 793No overall direction Food and the environment overall 233No overall direction All doses were below the dose limit

* Taken from the number of trend graphs for this sector presented in this report. This is a visual evaluation only.

3. Research establishments 23 4. Nuclear power stations

This section looks at the trends over the five years (2004-2008) from the UK’s nuclear power stations. The time trends show Key points the public’s exposure, discharges of radioactive waste and • All doses were less than the dose limit for concentrations of radionuclides in food and the environment. members of the public of 1 mSv per year The public’sexposure* (dose) from radioactive waste discharges • Highest annual dose (from artificial is assessed using radionuclide concentrations and gamma radionuclides) was 0.068 mSv at Heysham dose rates in the environment. • Most changes in dose between years resulted from natural changes in the environment There are a total of 19 nuclear power stations at 14 locations, • Overall decline in gaseous and liquid nine in England (Berkeley, Oldbury, Bradwell, Calder Hall, discharges, with all authorised discharges well Dungeness, Hartlepool, Heysham, Hinkley Point and Sizewell), below the authorised limits three in Scotland (Chapelcross, Hunterston and Torness) and • Two Magnox sites (Oldbury and Wylfa) two in Wales (Trawsfynydd and Wylfa). Eleven of the 19 remained operational whilst stations at nuclear power stations are first generation Magnox power Chapelcross, Dungeness and Sizewell stopped stations, seven are more recent advanced gas-cooled reactor generating electricity during the period (AGR) power stations and one is a pressurised water reactor • Concentrations on the land continued to be (PWR) power station. Five out of the original 11 first generation very low and concentrations in the sea were Magnox Power stations were operating in 2004. Over the 5 affected by natural changes in the year-period of this report three more stopped operating. This environment and/or influenced by other only left two operational in 2008, at Oldbury and Wylfa. sources.

4.1 Public’s exposure to radiation due to discharges of radioactive waste trend reflected changes between years in measured gamma dose rates.

Figure 12 shows the trends over the five years between 2004 The next group of people most affected by radioactive waste and 2008 of the public’sexposure to radiation due to the effects discharges was at Hinkley Point. This was also a group of local of liquid waste discharges at the power stations. fishermen, with annual doses ranging between 0.017 and 0.040 mSv over the five-year period. The doses were from The dose is made up from consuming seafood and external external radiation measured above beach sediment and a exposure over intertidal areas. External dose from intertidal conservative estimate from tritium and carbon-14 in fish. areas can be important contributor to dose where people spend Carbon-14 and tritium were likely due to discharges from the a lot of time on beach area. At all locations, around these sites, GE Healthcare facility at Cardiff. The trend graph shows an the doses were all less than the UK and European limit for increase in dose in 2006. The increase was due to slightly members of the public of 1 mSv per year. enhanced external dose rates above sediments. Variations in these measurements have contributed to the trend in recent Figure 12 shows the annual dose was highest to a group of years. There was no site related reason to account for the trend local fishermen at Heysham, ranging between 0.037 and in dose rates, and the changes between years was most likely 0.068 mSv over the five-year period, and with the highest value due to variations in natural radiation. in 2004. The doses were affected by past discharges from Sellafield, where radionuclides have travelled with currents People living near Berkeley and Oldbury received annual doses around to the area. The decrease in dose after 2004 was due between 0.006 and 0.028 mSv. This included external radiation, to a reduction in the amount of shellfish eaten (containing and a conservative estimate due to the tritium from Cardiff. americium-241 from past discharges from Sellafield). Most of The apparent increase in dose in 2008 was due to a higher the dose to this group was affected by external radiation gamma dose rate measured in a different type of sediment measured above beaches and tidal areas and variations in the (mud). Before 2008, the changes in dose were likely due to normal changes in the environment.

24 4. Nuclear power stations 2004 2005 2006 2007 2008 0.08 A

0.04 mSv

0 0.08 Torness L 0.08 B 0.04 mSv

0.04 mSv 0 Hunterston

0 Hartlepool

0.08 C 0.08 K

0.04 mSv 0.04 mSv A 0 Sizewell 0 L Chapelcross 0.08 D

K 0.04 0.08 J mSv

B 0 0.04 Bradwell mSv 0.08 E 0 Heysham J 0.04 mSv

I 0 Dungeness 0.08 I H

0.04 mSv C

0 Wylfa

D 0.08 H G

0.04 F mSv E

0 Trawsfynydd

0.08 0.08 G F

0.04 0.04 mSv mSv

0 0 Berkeley & Oldbury Hinkley

Figure 12. Individual radiation exposures around nuclear power stations from aquatic pathways for artificial radionuclides (2004-2008) (Small doses less than or equal to 0.005mSv are recorded as being 0.005mSv)

4. Nuclear power stations 25 Local fisherman at Chapelcross received annual doses ranging All assessed doses were much less than 0.005 mSv at both from 0.018 to 0.024 mSv over the five-year period. The Sizewell and Torness, over the five-year period, with no changes in doses were attributed to variations in gamma significant variation in doses to seafood consumers. dose rate measurements over sediments. The discharges from Chapelcross contributed a very small fraction of the dose to 4.2 Discharges of radioactive waste the local population. Most of the dose was attributed to from nuclear power stations historic Sellafield discharges. Authorised discharges of gaseous and liquid waste are made At Bradwell, the annual dose ranged from less than 0.005 to to the atmosphere and into the sea (except at Trawsfyndd 0.017 mSv. The highest dose was in 2007. In 2007, new where liquid discharges are released into Lake Trawsfynydd habits information became available including about occupancy – see section 4.4 for discharges). Figures 13 and 14 respectively, of boats at the main mooring locations. These data were show the trends of gaseous and liquid discharges over time included in the assessment of dose and lead to an increase (2004–2008) for a number of radionuclides. in the dose calculated for the group. Before 2007, the changes were mainly due to normal changes in the environment. In For Magnox stations, radionuclide authorisations include 2008, a decrease was observed in dose rate above beaches tritium and carbon-14 (gaseous), and tritium and caesium-137 and this lead to a decrease in doses to the group. (liquid). For operating Magnox stations authorised discharges of argon-41 and sulphur-35 gases are made. For AGR and PWR At Dungeness, the annual dose to a group of local bait diggers stations, these include tritium, carbon-14, sulphur-35 and or a group of people living on houseboats ranged between argon-41(for gaseous discharges), and tritium, sulphur-35, 0.007 and 0.014 mSv. The changes in dose were mainly due cobalt-60 and caesium-137 (for liquid discharges). to the normal variations in concentrations and dose rates in the environment. For the sites with only Magnox reactors (excluding Trawsfynydd – see section 4.4), the most significant trend over the five- At Hartlepool, between 2004 and 2007, the annual dose to year period was an overall decline in the gaseous discharges a group of local fishermen was assessed to be less than 0.005 of tritium and carbon-14 and liquid discharges of tritium and mSv over the period. The apparent increase in 2008 was due caesium-137. There was a pronounced decrease in the to the identification and assessment of a new pathway, for discharge of gaseous and liquid tritium from Chapelcross. This the external exposure of sea coal collectors. is because Chapelcross stopped generating electricity in 2004. Sizewell A and Dungeness A, both showed significant declines At Hunterston, the annual dose ranged from less than 0.005 in gaseous discharges of argon-41 and sulphur-35 after 2006. to 0.012 mSv. This included a contribution from technetium- This was the year that they were shut down permanently. 99 in shellfish, the activity having been discharged from Gaseous and liquid tritium discharges from Berkeley and Sellafield. Over the five-year period, the trend was due to Oldbury also reduced with time. Gaseous tritium and carbon- differences in measured gamma dose rates from normal 14 discharges at Bradwell were low and liquid discharges of changes in the environment. tritium decreased. Gaseous and liquid discharges at Wylfa were reasonably similar over the period (except for gaseous argon- At Trawsfynydd, the annual dose ranged between 0.008 and 41 which decreased overall and a peak increase in liquid 0.010 mSv over the five years. The assessed dose was for a tritium in 2005). group of anglers using the lake for fishing. Part of their dose was from external exposure. It has proved difficult to obtain For the sites with AGR or PWR reactors, the overall trend was a reliable dose rate from artificial radionuclides by measurement, an overall decline in gaseous and liquid discharges. The most because of uncertainty in the dose rate from natural pronounced observation was the decreases of gaseous and radionuclides. So for this assessment, external dose was liquid discharges in 2008 at Hartlepool. This is because both calculated from radionuclide concentrations (in particular reactors at Hartlepool were shut down in 2008. Gaseous and caesium-137) using an external dose rate model. Caesium- liquid tritium discharges from Hinkley Point and from 137 concentrations in sediments have declined over the 5 year Hunterston also reduced with time. Liquid tritium discharges period so the model predicts a reduction in dose rate. from Dungeness B and Heysham 1 and 2 also declined with time. In 2008, liquid tritium discharges reduced due to the At Wylfa, the annual dose to a group of people who ate a shutdown of Heysham 1. The most recent decrease Peak large amount of fish and shellfish ranges from less than 0.005 discharges occurred for gaseous tritium at Hinkley Point in 2006 to 0.007 mSv. The reduction in dose in 2004 at Wylfa was and for liquid tritium at Heysham in 2005. due to new estimates of consumption and occupancy rates. There was no significant trend in doses from marine pathways in recent years.

26 4. Nuclear power stations 100 Hunterston (gaseous) 10 Torness (gaseous) K Argon-41 Argon-41 Sulphur-35 x 10 Sulphur-35 x 100 A Tritium Tritium x 10 Carbon-14 Carbon-14 x 5 50

TBq 5 TBq

0 2004 2005 2006 2007 2008 0 2004 2005 2006 2007 2008

10 1000 Hartlepool (gaseous) Argon-41 Chapelcross (gaseous) Sulphur-35 x 100 B Tritium J Carbon-14 Tritium

500 5 TBq TBq

0 0 2004 2005 2006 2007 2008 2004 2005 2006 2007 2008

100 Heysham (gaseous) 50005000 Sizewell (gaseous) Argon-41 Argon-41 Sulphur-35 x 100 Tritium x 100 Tritium x 5 Carbon-14 x 100 I Carbon-14 x 10 A 50 2500 TBq K TBq C

0 2004 2005 2006 2007 2008 0 J 2004 2005 2006 2007 2008

100 Wylfa (gaseous) 0.10 Bradwell (gaseous) Argon-41 D Sulphur-35 x 10 B Tritium H Tritium x 5 Carbon-14 x 10 Carbon-14 x 5

50 0.50 TBq TBq I

0 0 2004 2005 2006 2007 2008 2004 2005 2006 2007 2008 H 100 Berkeley & Oldbury (gaseous)

G Argon-41 Tritium x 10 Carbon-14 x 10 Sulphur-35 x 10 50 TBq C

0 2004 2005 2006 2007 2008

D 100 Hinkley (gaseous) Argon-41 Sulphur-35 x 100 F Tritium x 10 G Carbon-14 x 5

50 F TBq E

0 2004 2005 2006 2007 2008

5000 Dungeness (gaseous) Argon-41 Sulphur-35 x 10000 E Tritium x 100 Carbon-14 x 100

2500 TBq

0 2004 2005 2006 2007 2008

Figure 13. Authorised discharges of gaseous wastes from nuclear power stations (2004-2008)

4. Nuclear power stations 27 1000 Hunterston (liquid) 1000 Torness (liquid)

K Tritium A Tritium Sulphur-35 x 100 Cobalt-60 x 100000 Cobalt-60 x 100000 q Bq 500

T 500 TB

0 0 2004 2005 2006 2007 2008 2004 2005 2006 2007 2008

0.10 Chapelcross (liquid) 1000 Hartlepool (liquid) B Tritium Tritium Sulphur-35 x 100 J Cobalt-60 x 10000 0.05

TBq 500 TBq

0 2004 2005 2006 2007 2008 0 2004 2005 2006 2007 2008

1000 Heysham (liquid) 100 Tritium Sizewell (liquid) Sulphur-35 x 100 Cobalt-60 x 10000 Tritium I C Caesium-137 x 10 A 500 50 TBq K TBq

0 0 2004 2005 2006 2007 2008 2004 2005 2006 2007 2008 J 1.0 100 Wylfa (liquid) Bradwell (liquid)

D Caesium-137 H Tritium Tritium B

q 50 0.5 TBq TB

0 I 0 2004 2005 2006 2007 2008 2004 2005 2006 2007 2008

1.0 Berkeley & Oldbury (liquid) H Caesium-137 G Tritium

0.5 TBq

0 2004 2005 2006 2007 2008

1000 Hinkley (liquid) F D Tritium Sulphur-35 x 100 Cobalt-60 x 10000

Bq 500 Caesium-137 x 100

T G

F 0 2004 2005 2006 2007 2008 E

1000 Dungeness (liquid)

Tritium E Caesium-137 x 1000 Sulphur-35 x 100 Cobalt-60 x 10000

500 TBq

0 2004 2005 2006 2007 2008

Figure 14. Authorised discharges of liquid wastes from nuclear power stations (2004-2008)

28 4. Nuclear power stations 4.3 Concentrations of radionuclides 4.4 Trawsfynydd – Discharges of in food and the environment radioactive waste and concentrations of radionuclides in Monitoring of food and the environment is carried out around the environment each of the power stations in the UK. The majority of measurements of radionuclide concentrations were at or below the analytical limits of detection. This meant that it was Trawsfynydd power station is authorised to discharge low levels only possible to establish trends for a few radionuclides in of liquid waste to Lake Trawsfynydd. All the other power environmental samples. Figure 15 shows monitoring trends stations make liquid discharges to the coastal environment. of caesium-137 in sediments from marine locations to help Figure 16 shows the trends of gaseous and liquid discharges assess the overall impact on the surrounding environment. over time (2004–2008) for a number of the authorised Furthermore, it is difficult to differentiate the low concentrations radionuclides. Gaseous tritium discharges from Trawsfynydd of activity in marine material between site discharge and slightly increased in recent years, peaking in 2007, whilst other factors such as liquid discharges of nearby sites, fallout liquid tritium discharges reduced with time. from weapons testing and Chernobyl, and long distance contributions (including past discharges) from nuclear Figure 16 also shows trends of caesium-137 in lake sediments reprocessing plants at Sellafield and Cap de la Hague (France). from Trawsfynydd to help assess the overall impact on the surrounding environment. In the lake itself, there remains clear Overall, the concentrations of caesium-137 in UK sediments evidence of the effects of caesium-137 discharges from the were low over time at all locations. Data in Figure 15 show power station, particularly in sediment. A substantial decline that, although there were minor changes between years for in environmental radionuclide concentrations was observed individual sites, the general trends were for activity in the late 1990s in line with reducing discharges. Over the concentrations to decrease or remain relatively constant over last five years (and more), the observed concentrations were the five-year period. The declining trend was most pronounced mainly affected by sample variability, including movement of at Chapelcross and Heysham; the two power station sites (near activity on sediments from beneath the sediment surface. the Irish Sea) most influenced by Sellafield. Further afield, the Nevertheless, the lowest caesium-137 concentrations in effects of Sellafield were less noticeable, partly due to the sediments were observed in 2007 and 2008. influence of releases from other sources and environmental variability.

4. Nuclear power stations 29 100 Hunterston

K 100 Torness (dry) -1 50 A Bq kg (dry) -1 50 Bq kg 0 2004 2005 2006 2007 2008

0 2004 2005 2006 2007 2008

200 Chapelcross 100 Hartlepool 150 J B (dry) -1 100 (dry) -1

Bq kg 50

50 Bq kg

0 2004 2005 2006 2007 2008 0 2004 2005 2006 2007 2008

100 Sizewell 100 Heysham C I

A (dry) -1 (dry) 50 -1 50

K Bq kg Bq kg

0 0 2004 2005 2006 2007 2008 2004 2005 2006 2007 2008 J 100 Bradwell

100 Wylfa D (dry) H B -1 50 (dry) Bq kg -1 50 Bq kg

0 I 2004 2005 2006 2007 2008

0 2004 2005 2006 2007 2008 H 100 Berkeley & Oldbury G (dry) -1 50 Bq kg C

0 2004 2005 2006 2007 2008

100 Hinkley D F G (dry) -1 50 Bq kg F E 0 2004 2005 2006 2007 2008

100 Dungeness E (dry)

-1 50 Bq kg

0 2004 2005 2006 2007 2008

Figure 15. Caesium-137 concentrations in marine sediments near nuclear power stations (2004-2008)

30 4. Nuclear power stations 1 Discharge (gaseous)

1200 Caesium-137 in lake sediment

Tritium 800 Carbon-14 x 10

(dry) 0.5 TBq -1 Bq kg

400

0 0 2004 2005 2006 2007 2008 2004 2005 2006 2007 2008

Porthmadog Trawsfynydd

0.1 Discharge (liquid)

Tritium Strontium-90 x 5 Caesium-137 x 5 0.05 TBq

0 2004 2005 2006 2007 2008

5 km

Figure 16. Authorised discharges of gaseous and liquid radioactive wastes and monitoring of the environment, Trawsfynydd (2004-2008)

4.5 Summary

The information presented in Table 4 gives an overview of trends associated with doses, discharges and environmental concentrations described in Section 4.

Table 4. Summary of trend data for nuclear power sector (2004-2008)*

Trend data Downwards No change Upwards Overall Gaseous discharges 831Majority downward trend Liquid discharges 921Majority downward trend Overall discharges 17 52Majority downward trend Food and the environment overall 660No overall direction All doses were below the dose limit

* Taken from the number of trend graphs for this sector presented in this report. This is a visual evaluation only.

4. Nuclear power stations 31 5. Defence establishments

This section looks at the trends over the five years (2004-2008) from the UK’s defence establishments. The time trends show Key points the public’s exposure, discharges of radioactive waste and • All doses were significantly less than the dose concentrations of radionuclides in food and the environment. limit for members of the public of 1 mSv per The public’sexposure* (dose) from radioactive waste discharges year is assessed using radionuclide concentrations and gamma • All doses (from artificial radionuclides) were dose rates in the environment. less than 0.005 mSv • All authorised discharges were well below the There are nine defence-related establishments that are currently authorised limits authorised to discharge radioactive waste in the UK. The • Overall, gaseous and liquid discharges were main sites are Aldermaston (and Burghfield) in Berkshire, low Devonport in Devon, Faslane and Coulport in Argyll and Bute, • Concentrations around the sites continued to and Rosyth in Fife. Other minor defence sites include Barrow be very low (Cumbria), Derby (Derbyshire), Holy Loch (Argyll and Bute) and Vulcan (Highland). These latter smaller sites make small discharges overall, and are not considered in detail here. Rosyth (liquid only) showed some minor changes over the 5.1 Public’s exposure to radiation due period, but the discharges were very low. to discharges of radioactive waste 5.3 Defence establishments – Figure 17 shows the trend of group doses over time (2004– Concentrations of radionuclides 2008) due to the effects of gaseous and liquid waste discharges. in food and the environment At all locations the doses were all less than 0.005 mSv over the whole five year-period, and much less than the national UK and European limit for members of the public of 1 mSv The Atomic Weapons Establishment at Aldermaston provides per year. and maintains fundamental components of the UK’s nuclear deterrent on behalf of the Ministry of Defence. Gaseous and 5.2 Aldermaston, Devonport, Faslane liquid discharges are released into the atmosphere and to the and Coulport, and Rosyth – sewage works at Silchester and to Aldermaston Stream. The Discharges of radioactive waste concentrations of all artificially detected radionuclides in the Thames catchment area were very low (or below the limit of detection). The gross alpha (and gross beta) activity Gaseous and liquid discharges (mainly tritium, carbon-14 and concentrations were below the World Health Organisation’s cobalt-60) are released into the atmosphere and to the sea. screening levels for drinking water over the whole period. Figure Figure 18 shows the trends of discharges over time (2004– 19 provides some monitoring trends to assess the impact on 2008) for a number of the authorised radionuclides. the surrounding environment. Concentrations of plutonium radionuclides and americium-241 (alpha emitting radionuclides) Gaseous tritium discharges from Aldermaston significantly in freshwater crayfish from Ufton Bridge to Theale also showed declined over the five-year period. Other gaseous radionuclides low levels. Concentrations of alpha emitting radionuclides in discharged from the site were very low and reasonably constant sediments at Aldermaston, Mapledurham and Pangbourne with time. The Pangbourne pipeline (which previously were shown to decrease initially. This corresponded with a discharged liquid waste to the River Thames at Pangbourne) reduction in liquid alpha emitting radionuclides from 2004. closed in 2005. Consequently, liquid discharges of tritium, alpha Any fluctuations in recent years, for both food and sediment, emitting radionuclides and plutonium-241 decreased after that. were most likely due to normal variations in the environment. At Devonport, gaseous and liquid discharges were relatively constant for tritium and cobalt-60 over the five years. Gaseous For other defence establishments, the majority of carbon-14 discharges were elevated in 2005 and 2006. measurements of food and environmental samples were at Gaseous and liquid discharges at Faslane and Coulport, and or below the analytical limits of detection, which made it difficult to produce trend data from monitoring results.

32 5. Defence establishments 2004 2005 2006 2007 2008

0.010 A

0.005 mSv

0 Rosyth

0.010 D

0.005 mSv

0 Faslane and Coulport D A

0.010 B

0.005 mSv

0 Aldermaston

0.010 C B

0.005 mSv

0 Devonport C

Figure 17. Individual radiation exposures to most exposed groups from artificial radionuclides, Aldermaston, Devonport, Faslane and Coulport, and Rosyth (2004-2008) (Doses less than 0.005mSv are recorded as being 0.005mSv)

5. Defence establishments 33 0.5 Faslane and Coulport (liquid) D

Tritium 0.25 Cobalt-60 x 1000 TBq 0.005 Rosyth (liquid) A

Tritium Cobalt-60 0 2004 2005 2006 2007 2008 0.0025 TBq

0.01 Faslane & Coulport (gaseous) D Tritium 0 2004 2005 2006 2007 2008

0.005 TBq D A

0 2004 2005 2006 2007 2008

0.1 Aldermaston (liquid) Tritium Alpha x 1000 B Plutonium-241 x 1000

0.05 TBq

0 2004 2005 2006 2007 2008

50 Aldermaston (gaseous) B Tritium Alpha x 1000000 Carbon-14 x 1000000 Plutonium-241 x 1000000 Krypton-85 x 100 0.5 Devonport (liquid) 25 TBq C

Tritium Cobalt-60 x 100 0.25 0 TBq 2004 2005 2006 2007 2008

B 0 2004 2005 2006 2007 2008

0.01 Devonport (gaseous) C C

0.005 Carbon-14

TBq Tritium

0 2004 2005 2006 2007 2008

Figure 18. Authorised discharges of gaseous and liquid radioactive wastes, Aldermaston, Devonport, Faslane and Coulport, and Rosyth (2004-2008)

34 5. Defence establishments 400 Alpha activity (sediment) at Pangbourne 400 Alpha activity (sediment) at Mapledurham (dry) (dry) -1 200 -1 200 Bq kg Bq kg

0 0 2004 2005 2006 2007 2008 2004 2005 2006 2007 2008

Mapledurham

Ufton bridge R. Thames Pangbourne Theale

0.005 Activity (signal crayfish) at Ufton bridge- Theale

Plutonium-239+240

-1 Americium-241 0.0025 Bq kg

R. Kennett 0 2004 2005 2006 2007 2008

400 Alpha activity (sediment) at Aldermaston Aldermaston (dry)

-1 200 Aldermaston Bq kg

0 2004 2005 2006 2007 2008 5km

Figure 19. Monitoring of the environment from discharges of radioactive wastes, Aldermaston (2004-2008)

5.4 Summary

The information presented in Table 5 gives an overview of trends associated with doses, discharges and environmental concentrations described in Section 5.

Table 5. Summary of trend data for defence sector (2004-2008)*

Trend data Downwards No change Upwards Overall Gaseous discharges 111No overall direction Liquid discharges 112No overall direction Overall discharges 223No overall direction Food and the environment overall 301Majority downward trend All doses were below the dose limit

* Taken from the number of trend graphs for this sector presented in this report. This is a visual evaluation only.

5. Defence establishments 35 6. Radiochemical production

This section looks at the trends over the five years (2004-2008) from the UK’s radiochemical production sites. The time trends Key points show the public’s exposure, discharges of radioactive waste • All doses were less than the dose limit for and concentrations of radionuclides in food and the members of the public of 1 mSv per year environment. The public’s exposure* (dose) from radioactive • Highest annual dose (from artificial waste discharges is assessed using radionuclide concentrations radionuclides) was 0.029 mSv at Cardiff and gamma dose rates in the environment. GE Healthcare is • Highest group dose continually decreased with a health science company operating in worldwide commercial time healthcare and life science markets, with radiochemical facilities • All authorised discharges were well below the at Amersham, Cardiff and a small legacy waste processing unit authorised limits at Harwell. The trends of the Harwell facilities are covered under • Concentrations on the land continued to be Section 3 (Research establishments). very low and concentrations in the sea declined following reduction in discharges. 6.1 Public’s exposure to radiation due to discharges of radioactive waste 6.2 Amersham – Discharges of radioactive waste and Figure 20 shows the trend over the five years between 2004 concentrations of radionuclides in and 2008 of the public’sexposure to radiation due to the effects food and the environment of gaseous and liquid waste discharges. For locations near both sites, the doses were all much less than the UK and European Gaseous and liquid discharges from Amersham are released limit for members of the public of 1 mSv per year. into the atmosphere and to sewers serving the Maple Lodge sewage works. Releases subsequently enter the Grand Union The annual dose was highest at Cardiff from consuming fish Canal and the River Colne. Figure 21 shows the trends of and shellfish (combined with external exposure), and ranged discharges over time (2004–2008) for a number of the between 0.012 and 0.029 mSv over the five-year period with authorised radionuclides. a clear decline with time. The reduction in the doses for the Cardiff site was largely due to the continuing reductions in The gaseous discharges were low over the five-year period. concentrations of tritium (and carbon-14) in seafood, with the Discharges of iodine-125 declined over the period, whilst most significant reduction of tritium in seafood occurring in radon-222 and sulphur-35 generally increased. Limits for 2006. selenium-75 were removed in 2008. There was an overall reduction in liquid discharges of tritium, iodine-125 and At the Amersham site, the annual dose to people who ate caesium-137. locally grown food (combined with a contribution of discharged radionuclides in air) ranged between 0.015 and 0.020 mSv Figure 21 also provides monitoring trends of sulphur-35 and over the five years. The changes in trends at this site were mainly caesium-137 in food and in grass and sediment from three due to variations in the estimated air exposure from inhaling locations, to assess the impact on the surrounding environment. gases and emitted radiation of the gaseous discharges. Caesium-137 concentrations in sediment were low over the period and changes were attributed to natural variation. Although concentrations appeared to increase over time, at the outfall these were lower than further upstream. Caesium- 137 activity was likely due to fallout from weapons testing and Chernobyl. The trend for sulphur-35 concentrations in grass generally followed the pattern of gaseous discharges, although the activity concentrations were very low. In spinach, sulphur- 35 concentrations were significantly less than in grass.

36 6. Radiochemical production 2004 2005 2006 2007 2008

0.04 0.04 A B

0.02 0.02 mSv mSv

0 0 Amersham (terrestrial) Cardiff (aquatic)

20 km

Figure 20. Individual radiation exposures to most exposed groups from artificial radionuclides, Amersham and Cardiff (2004-2008)

6.3 Cardiff – Discharges of radioactive Figure 22 also provides monitoring trends of tritium, carbon- waste and concentrations of 14 and caesium-137 in seafood and from three locations, to radionuclides in food and the assess the impact on the surrounding environment. Overall, environment the trend was for concentrations of tritium in fish, molluscs and sediments to decline over the five years, in line with The gaseous discharges into the atmosphere from the Maynard recent reductions in liquid discharges. This also included the Centre, Cardiff, mainly consisted of tritium and carbon-14, low tritium concentrations being detected in sediment from with smaller amounts of phosphorus-32+33 and iodine-125 the Glamorganshire canal, which is not used as a source of also released. Liquid waste is released into the Ystradyfodwg water for public water supply. and Pontypridd public sewer. This joins the Cardiff East sewer, which after passing through a waste water treatment works, Over the five-year period, concentrations of carbon-14 and discharges into the Severn estuary near Orchard Ledges. caesium-137 in seafood and sediments were low and relatively Figure 22 shows the trends of discharges over time (2004– constant. Carbon-14 concentrations detected in sediment 2008) for a number of the authorised radionuclides. from the Glamorganshire canal declined after 2005. Changes between years were most likely due to normal changes in the In 2004, the Environment Agency issued a new authorisation environment, with caesium-137 coming from other nuclear for the site, which reduced all authorisation limits. Gaseous establishments and fallout from weapons testing and discharges of iodine-125 and phosphorus radionuclides Chernobyl. declined over the five-year period, with a step decrease in 2005. Whilst tritium and carbon-14 showed some minor variations, their trends were broadly similar to each other. Overall, liquid discharges declined over the period for each of the radionuclides, and were much lower by 2008.

6. Radiochemical production 37 Grand Union Canal 20 Caesium-137 (sediment) River Colne Upstream R iv Outfall (GUC) e ry) r C -1 h 10 e s

Bq kg (d Orchard s

Amersham

0 site 2004 2005 2006 2007 2008

l 4 km

r Co

River Thames U

Rive d

2 Sulphur-35 (spinach)

-1 1 Bq kg (fresh) 0.02 Sulphur-35 (gaseous)

0 2004 2005 2006 2007 2008

0.01 TBq 10 Sulphur-35 (grass)

0.002 Tritium (liquid) esh)

0 -1 5 2004 2005 2006 2007 2008 Next to site Bq kg (fr Orchard next to site 0.0004 Water Meadows (River Chess) 0.001 Selenium-75 (gaseous) TBq

0 2004 2005 2006 2007 2008

Bq 0.0002 0

T 2004 2005 2006 2007 2008

0.0001 Iodine-125 (liquid)

0 2004 2005 2006 2007 2008

0.002 Iodine-125 (gaseous) 0.00005 TBq

0.001 0 TBq 2004 2005 2006 2007 2008

0.00002 Caesium-137 (liquid)

0 2004 2005 2006 2007 2008

0.00001 5 Radon-222 (gaseous) TBq

2.5 0

TBq 2004 2005 2006 2007 2008

0 2004 2005 2006 2007 2008

Figure 21. Authorised discharges of gaseous and liquid radioactive wastes and monitoring of the environment, Amersham (2004-2008)

6.4 Summary

The information presented in Table 6 gives an overview of trends associated with doses, discharges and environmental concentrations described in Section 6.

Table 6. Summary of trend data for radiochemical production (2004-2008)*

Trend data Downwards No change Upwards Overall Gaseous discharges 603Majority downward trend Liquid discharges 601Majority downward trend Overall discharges 12 04Majority downward trend Food and the environment overall 521Majority downward trend All doses were below the dose limit

* Taken from the number of trend graphs for this sector presented in this report. This is a visual evaluation only.

38 6. Radiochemical production 0.000003 200 Phosphorus-32+33 (gaseous) Tritium (gaseous) 3 Carbon-14 (gaseous)

100 0.0000015

1.5 TBq TBq TBq

0 0 0 2004 2005 2006 2007 2008 2004 2005 2006 2007 2008 2004 2005 2006 2007 2008

0.02 Sulphur-35 (gaseous) 0.0001 Iodine-125 (gaseous)

0.01 0.00005 TBq TBq

0 0 2004 2005 2006 2007 2008 2004 2005 2006 2007 2008

500 Activity (sediment) Canal 200 Activity (sediment) west of pipeline 200 Activity (sediment) east of pipeline Tritium Carbon-14 Tritium Caesium-137 Tritium Carbon-14 Carbon-14 Caesium-137 Caesium-137 (dry) (dry) -1 (dry) 250 -1 100 -1 100 Bq kg Bq kg Bq kg

0 0 0 2004 2005 2006 2007 2008 2004 2005 2006 2007 2008 2004 2005 2006 2007 2008

Glamorganshire Canal Cardiff site

7000 Activity (molluscs)

Tritium 0.00003 Iodine-125 (liquid) Carbon-14 x 10 Caesium-137 x 1000

(fresh) 3500 -1

0.000015 Bq kg TBq

0 River 2004 2005 2006 2007 2008 0 2004 2005 2006 2007 2008 Taff

50 Tritium (liquid) Sewage 7000 Activity (fish) Works

Tritium 25 Carbon-14 x 10 TBq Caesium-137 x 1000

(fresh) 3500 -1 Bq kg 0 2004 2005 2006 2007 2008

0.3 Carbon-14 0 (liquid) 2004 2005 2006 2007 2008

0.15 TBq

0 2004 2005 2006 2007 2008 Orchard Ledges 0.0000050 Phosphorus-32+33 (liquid) Severn Estuary

0.0000025 TBq

0 1 km 2004 2005 2006 2007 2008

Figure 22. Discharges of gaseous and liquid radioactivity wastes and monitoring of the environment, Cardiff (2004-2008)

6. Radiochemical production 39 Summary and Conclusions

We have noted that over 2004 to 2008 discharges have shown a distinct decline in three of the five sectors. However, Key points environmental concentrations have responded relatively slowly Information presented in Table 7 gives an to these reductions. This is in part due to the legacy of higher overview of trends associated with discharges and environmental concentrations of radionuclides from past environmental concentrations for each of the five higher discharges. As discharges have fallen further, nuclear sectors described in Sections 2 – 6. The key environmental concentrations have reduced more slowly points are given below. because levels are being sustained from this legacy. • Discharge trends were downward in three of the five sectors with no clear trends in the We have not made an assessment of the overall dose trends other two sectors by sector. This is because doses are dependent on a number • Trends of radionuclide concentrations in food of inputs, including the method of assessment, concentrations and the environment were downward in two of radionuclides in food and the environment, measurements of the five sectors with no clear trends in the of dose rates and data on human activities. All these are other three sectors subject to variation and changes from year to year which can • Doses at all sites were less than the dose limit, affect the dose assessment outcomes and produce step and in most cases much less changes or false trends over the relatively short time of 5 years. We think that a longer time period of 10 years is required to provide a stronger basis to confirm overall dose trends.

Additional information on past discharges, radionuclide concentrations and doses for each year can be found in the RIFE reports.

Table 7. Overall summary for nuclear sectors (2004-2008)*

Sector 2004-2008 trend

All sectors Key Marine Environmental Indicators Majority downward trend Total diet No change, variation from year to year Nuclear fuel processing Discharges Majority downward trend Food and environmental concentrations Majority downward trend. Research sites Discharges No overall trend Food and environmental concentrations No overall trend Power production Discharges Majority downward trend Food and environmental concentrations No overall trend Defence sites Discharges No overall trend Food and environmental concentrations Majority downward trend Radiochemical production Discharges Majority downward trend Food and environmental concentrations Majority downward trend * Taken from the trends presented in this report. This is a visual evaluation only.

40 Summary and Conclusions

Environment Agency Radiological Monitoring and Assessment National Operations Group Lutra House, Off Seedlee Road, Walton Summit Bamber Bridge Preston PR5 8BX

Food Standards Agency Food Protection Division Aviation House 125 Kingsway London WC2B 6NH

Northern Ireland Environment www.ni-environment.gov.uk Agency

Northern Ireland Environment Agency Industrial Pollution and Radiochemical Inspectorate Klondyke Building Cromac Avenue Lower Ormeau Road Belfast BT7 2JA

Scottish Environment Protection Agency Radioactive Substances Policy Unit Erskine Court The Castle Business Park Stirling FK9 4TR

ISBN: 978 0 907545 34 7