Geological Disposal Facility Design

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CIVE5707M: Integrated design project IVStakeholder: National Nuclear Laboratory (NNL)Client: Professor P. Purnell

University Of Leeds, School of Civil Engineering Session 2012/2013

Group 12:Alexander CarrBen Fadida

James KingmanHonor NewmanRomain SidotiJoshua Wood


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ABSTRACT

To cope with our legacy and future nuclear waste production within the United Kingdom, a solutionwas required to facilitate the disposal of the nuclear waste. Geological disposal has been selected, bythe UK government, as the preferred option for the long-term management of nuclear waste. Sizewell

was selected as the most appropriate location to situate a Geological Disposal Facility (GDF).Detailed designs for the surface and subterranean facilities were developed, based on the NDAspecifications, and the identified site. Transport of existing nuclear waste, by sea, directly fromSellafield to Sizewell was identified as the most appropriate method of transport.

The GDF facility will remain operational until 2222, after which the facility will be backfilled, andthe site redeveloped to ensure future safety. A combination of stewardship and archives, along withdurable markers, have been proposed to ensure that knowledge of the dangers of the site aremaintained over the many tens of thousands of years that the waste will remain radioactive.


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Table of Contents1. Pre-Qualification Exercise: Preliminary assessment of proposed sites ......... 1

1.1 Introduction .............................................................................................. 1

1.2 West Cumbria ........................................................................................... 1 1.2.1 Introduction ..................................................................................................................... 1 1.2.2 Transport links ................................................................................................................. 1 1.2.3 Natural capital of the area ................................................................................................ 1 1.2.4 Community opposition ..................................................................................................... 2 1.2.5 Topography ...................................................................................................................... 2 1.2.6 Geology ............................................................................................................................ 3

1.2.6.1 Carboniferous rocks ............................................................................................................ 3 1.2.6.2 Permian, Jurassic and Triassic rocks .................................................................................... 3

1.2.6.3 Ordovician rocks .................................................................................................................. 3 1.2.7 Conclusion ........................................................................................................................ 4

1.3 Romney Marsh, Kent ................................................................................. 4 1.3.1 Introduction ..................................................................................................................... 4 1.3.2 Level of Experience within Nuclear Industry and Employment Benefits ........ ........ ......... ..... 4 1.3.3 Transport Links ................................................................................................................. 4 1.3.4 Natural Capital of the Area ............................................................................................... 4 1.3.5 Community Opposition ..................................................................................................... 5 1.3.6 Geology ............................................................................................................................ 5

1.3.6.1 Sub-surface Unsuitability Test ............................................................................................. 5 1.3.6.2 Topography, Geomorphology and Flood Risk ..................................................................... 6

1.4 Selection of alternative site for geological disposal facility ........................ 7

1.5 Sizewell ..................................................................................................... 7 1.5.1 Community opposition ..................................................................................................... 8 1.5.2 Earthquake and fault zones ............................................................................................... 8 1.5.3 Topography ...................................................................................................................... 9 1.5.4 Flooding ........................................................................................................................... 9

1.5.5 Transport ......................................................................................................................... 9 1.5.6 Geology ............................................................................................................................ 9

1.6 Decision Making Procedure ..................................................................... 10 1.6.1 Weightings ..................................................................................................................... 10 1.6.2 Uncertainty .................................................................................................................... 11 1.6.3 Weighted Average Multipliers ........................................................................................ 11

1.7 Decision Matrix ....................................................................................... 12

1.8 Conclusion .............................................................................................. 13

2. Pre-Qualification exercise: Design Development ....................................... 14


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2.1 Introduction ............................................................................................ 14

2.2 Waste Quantities for Disposal ................................................................. 14 2.2.1 Data Sources .................................................................................................................. 14

2.2.1.1 The 2010 UK Radioactive Waste Inventory (UKRWI) ........................................................ 14 2.2.1.2 The 2010 Estimate of Waste for Geological Disposal (EWGD) .......................................... 14 2.2.1.3 Nirex Report N/085 ........................................................................................................... 15

2.2.2 Assumptions................................................................................................................... 15 2.2.2.1 Nuclear New Build Program .............................................................................................. 15 2.2.2.2 Spent Fuel, Uranium and Plutonium ................................................................................. 15 2.2.2.3 Waste Quantity Conversions ............................................................................................. 15

2.2.3 Waste Quantities for Design ........................................................................................... 16 2.2.4 Waste Locations for Design ............................................................................................. 16

2.3 Transportation of Waste to Site .............................................................. 17 2.3.1 Modes of Transport ........................................................................................................ 17

2.3.1.1 Transport by Sea ............................................................................................................... 17 2.3.1.2 Transport by Rail ............................................................................................................... 17 2.3.1.3 Transport by Road ............................................................................................................. 17

2.3.2 Options for Transport ..................................................................................................... 17 2.3.2.1 Option 1 ............................................................................................................................. 18 2.3.2.2 Option 2 ............................................................................................................................. 18 2.3.2.3 Option 3 ............................................................................................................................. 18 2.3.2.4 Option 4 ............................................................................................................................. 18

2.3.2.5 Option 5 ............................................................................................................................. 18 2.3.2.6 Transport Option Preference Hierarchy ............................................................................ 18

2.3.3 Selection of Modes of Transport for Existing Sites ........................................................... 18 2.3.4 Logistics and Delivery Rates ............................................................................................ 19

2.3.4.1 Transport Vessels .............................................................................................................. 19 2.3.4.2 Accident Rates and Risk Assessment ................................................................................ 20 2.3.4.3 Summary of Logistics ......................................................................................................... 20

2.4 Design specification: Development of the brief ....................................... 21 2.4.1 Surface Facilities ............................................................................................................. 21

2.4.2 Underground Operational Requirements ........................................................................ 22 2.4.3 Waste Transport and Infrastructure Requirements .......................................................... 22 2.4.4 Safety ............................................................................................................................. 22 2.4.5 Sustainability and environmental impacts ....................................................................... 23

2.5 Preliminary Design of Proposed Sites in Sizewell ..................................... 23 2.5.1 Introduction ................................................................................................................... 23 2.5.2 Location of Sites ............................................................................................................. 24 2.5.3 Constraints and Opportunities ........................................................................................ 25

2.5.3.1 Site 1 .................................................................................................................................. 25

2.5.3.2 Site 2 .................................................................................................................................. 25 2.5.4 Conceptual layouts for Surface Facilities .......................................................................... 26


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2.5.4.1 Surface Facilities layouts ................................................................................................... 26 2.5.4.2 Decision Matrix ................................................................................................................. 28

2.5.5 Conceptual layouts for Underground Facilities................................................................. 29 2.5.5.1 Decision Matrix ................................................................................................................. 29

2.6 Emplacement Process ............................................................................. 30 2.6.1 Surface Handling Processes ............................................................................................. 30

2.6.1.1 Sea ..................................................................................................................................... 30 2.6.1.2 Unloading .......................................................................................................................... 30 2.6.1.3 Site check in ....................................................................................................................... 30 2.6.1.4 Waste Package Transfer Facility ........................................................................................ 30 2.6.1.5 Drift Tunnel ....................................................................................................................... 30

2.6.2 Surface Facility Process Flow Chart .................................................................................. 31 2.6.3 Underground Handling Processes (Nuclear Decomissioning Authority, 2010) ..... ........ ...... 32

2.7 Detailed design ....................................................................................... 33 2.7.1 Surface Facility ............................................................................................................... 33

2.7.1.1 Operational Site Layout ..................................................................................................... 33 2.7.1.2 Construction Phase Site Layout ......................................................................................... 35 2.7.1.3 Waste Reception and Handling Facilities .......................................................................... 35 2.7.1.4 Port .................................................................................................................................... 35

2.7.2 Underground Facilities .................................................................................................... 36 2.7.2.1 Underground Facility detailed design ............................................................................... 36

2.7.3 Construction of the Underground Facilities and Backfilling .............................................. 38 2.7.3.1 Excavation methods .......................................................................................................... 38 2.7.3.2 Construction Process ......................................................................................................... 38 2.7.3.3 Backfilling .......................................................................................................................... 38 2.7.3.4 Spoil Management ............................................................................................................ 39

2.8 Method Statement .................................................................................. 40

2.9 Risk Assessment ...................................................................................... 41

3. Prequalification Exercise: Post-Closure ..................................................... 42

3.1 Post Closure Management ...................................................................... 42

3.2 Near Term Post Closure ........................................................................... 42 3.2.1 Considered Near Term Post Closure Uses ........................................................................ 42 3.2.2 Recommended Near Term Post Closure Use .................................................................... 44

3.3 Long Term Post Closure Management Approaches .................................. 44 3.3.1 Passive Institutional Control ........................................................................................... 44 3.3.2 Active Institutional Control ............................................................................................. 44 3.3.3 Total Abandonment ........................................................................................................ 44 3.3.4 The Communities Legacy ................................................................................................ 44 3.3.5 Adopted Approaches ...................................................................................................... 45 3.3.6 Adopted Passive Institutional Controls ........ ......... ........ ........ ........ ......... ........ ........ ........ . 45


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3.3.7 Adopted Active Institutional Controls ........................................................................... 46

3.4 Backfilling ............................................................................................... 46 3.4.1 Public Opinion ................................................................................................................ 46 3.4.2 Ethics ............................................................................................................................. 46 3.4.3 Costs .............................................................................................................................. 46 3.4.4 Safety and Safeguards .................................................................................................... 47

3.5 Project Timeline ...................................................................................... 47

Appendix A ................................................................................................... 48

Appendix B ................................................................................................... 49

Appendix C ................................................................................................... 50

Appendix D ................................................................................................... 51 Appendix E .................................................................................................... 52

Appendix F .................................................................................................... 53

Appendix G ................................................................................................... 56

Appendix H ................................................................................................... 58

Appendix I .................................................................................................... 61

Appendix J .................................................................................................... 64

Appendix K ................................................................................................... 65

Appendix L .................................................................................................... 67

Appendix M .................................................................................................. 70

Appendix N ................................................................................................... 74

Appendix O ................................................................................................... 79

Appendix P ................................................................................................... 93

Appendix Q ................................................................................................... 96

Appendix Project Implementation Plan .................................................... 100

Appendix- Meeting Minutes ....................................................................... 104

Appendix Full Brief ................................................................................... 122

Works Cited ................................................................................................ 130


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Table of Figures

Figure 1: West Cumbria Topography ......................................................................................... 2 Figure 2: Water Flow in Cumbria .............................................................................................. 3

Figure 3: Historic Coastline Contours ........................................................................................ 7 Figure 4: Earthquake history in the UK ...................................................................................... 8 Figure 5: Geological Fault zones in the UK ................................................................................ 8 Figure 6: Map of Sizewell ......................................................................................................... 24 Figure 7: Sizewell site 1 area .................................................................................................... 26 Figure 8: Sizewell site 2 area .................................................................................................... 26 Figure 9: Surface facilities conceptual design ......................................................................... 27 Figure 10: Process flow chart ................................................................................................... 31 Figure 11: Operational Site layout ........................................................................................... 34 Figure 12: Underground facility detailed design ..................................................................... 37 Figure 13: Marker stone sketch ............................................................................................... 45 Figure 14: Visitor center sketch ............................................................................................... 45 Figure 15: Project Timeline ...................................................................................................... 47


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1. Pre-Qualification Exercise: Preliminaryassessment of proposed sites

1.1 IntroductionThe Government has undertaken a search for possible geological disposal facility sites on a purelyvoluntary basis, stating that a repository will only be put somewhere where the geology is suitableand there is a community that has volunteered to have it (West Cumbria Managing RadioactiveWaste Safely Partnership, 2012).There are currently three local communities that have expressed interest in further exploring theopportunity of facilitating a GDF; these comprise of Allerdale and Copeland, which are both situatedin West Cumbria, along with Romney Marsh in Kent. There is also Sizewell, in Suffolk, which,although has not volunteered as a site, is currently being assessed for suitability.

As an incentive to encourage communities to accept the proposed geological disposal facility, the

Government is offering community benefits packages that will include substantial long-terminvestment into infrastructure, services and skills that will benefit the community as a whole.

1.2 West Cumbria

1.2.1 Introduction

Allerdale is one of six districts that makes up Cumbria, and is located in the West of the county,approximately 37km (Google Earth, 2012) away from the Sellafield site. Also situated in WestCumbria, Copeland is just 7km (Google Earth, 2012) away from the Sellafield site.

West Cumbria has a long history of nuclear industry with the Sellafield nuclear power plant beingcommissioned in 1956. (Sellafield Ltd, Unknown). The question is being raised as to whether they

should develop the area in to a local hub of excellence recognised internationally, or diversify.

1.2.2 Transport links

The presence of existing transport links is important, though not essential, when choosing the locationfor the GDF. Due to the length of time the facility will be operational for, it is important to considerseveral different methods of transport for each location. The mode of transport used for movingnuclear waste could change, and the potential cost of this to the project must be considered.

Both of the potential Cumbrian locations are close to existing rail links but lack sufficient road links.The nearest motorway (M6) is too far away from both of the sites to be used for regular transport of waste. For either Allerdale or Copeland to be chosen as the final location, significant improvement tothe road network must take place, which would be difficult in an area with a large area of protected

land. The nearest airfield is at Carlisle Airport, approximately 90km (Google Earth, 2012) by roadfrom Copeland, and 45km (Google Earth, 2012) from Allerdale.

1.2.3 Natural capital of the area

The presence of protected land and sites of special scientific interest could affect the decision on anyof the potential locations. Although close to the Lake District, Eskdale, in the Copeland district, hasan only small area of scientific interest surrounding it. There are small areas marked as nature reserves,although not in the immediate vicinity of Eskdale.

Silloth has the largest areas of special scientific areas of all the locations that are being considered,with relatively large nature reserve areas. (Natural England, Unknown)


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1.2.4 Community opposition

Many locals believe that the reputation of the entire area would be diminished if a GDF were to bebuilt in West Cumbria. Tourism brought in over 2.2 billion to the local economy in 2011 (CumbriaTourism, Unknown). People would be less willing to visit on holiday, and potentially wary of movingto the locality. This would affect the tourism and property values.

With the Lake District National Park being located in Cumbria, many people are opposed to the ideaof storing such hazardous waste under one of arguably the most beautiful parts of England. Localresidents rallied together in early 2012 and sent a postcard card to the Lake District National Park titled Remembering Chernobyl (Radiation Free Lakeland, 2012) demonstrating the fear the publicshare. There is also great uncertainty over what will be done with the spoil from the excavation of theunderground facility. There will be approximately the same amount as that from the channel tunnelexcavation (West Cumbria Managing Radioactive Waste Safely Partnership, 2012).

Some 68% of Copeland residents and 51% of Allerdale residents (World Nuclear News, 2012) are infavour of further investigation into the possibility of a geological disposal facility. This shows thatwhile there is great concern over the project, local communities are still in favour of furtherinvestigating the possibilities.

1.2.5 Topography

The technical aspects of a particular area both underground (geology) and over ground (topography)should be considered when looking at the suitability of West Cumbria in hosting a geological disposalfacility. A Topographic relief map of West Cumbria illustrating the difference in ground elevation of the partnership area reflects non-uniformity in the terrain.High mountainous areas lie in the eastern part of West Cumbria in the Lake District region. Thesemountainous chains continue south of Copeland but the terrain is much more subdued north of Allerdale on the Solway lowlands and along the coast of the Irish Sea.

It is clear from the color-coding of the above relief maps that the terrain is not leveled. Thetopography of the West Cumbria area should be sufficient to disregard it as an option for a geologicaldisposal facility because "water flow is driven by the elevation of mountains and inevitably rises tosurface as 'artesian' springs" (Smythe, 2010) as illustrated in figure 2 below.

0 m 1000 m

Figure 1- West Cumbria topography (Smythe, 2010)


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The high mountains of the Lake District willcreate a strong flow of water from East to Westtowards the Irish Sea, causing safety hazards assuitable aquifers from the Sherwood sandstonegroup are present along the coast. The Sherwoodsandstone group is the main aquifer that isexploited in the area and should not be in contactwith any nuclear waste in order to protect ourpresent or possible future water drinking systems.

Different relief maps of geological disposal facility sites around the world in Sweden and Finland inAppendix A show that a low relief system was chosen as compared to West Cumbria (Smythe, 2010).

1.2.6 Geology

The geology of West Cumbria varies enormously with a mixture of carboniferous, Triassic andOrdovician rocks. The Lake District area (Comprising North Copeland and South Allerdale) is mainlycomposed of the Ordovician group of rocks that includes the Eycott and Borrowdale Volcanic groupsand the Skiddaw group. Towards the more subdued terrain of West Cumbria in the Solway lowlandsas well as along the coast from St Bees towards Haverigg, younger carboniferous and Triassic rocksunderlie these ancient rocks and thicken towards the Irish Sea and Solway lowlands (BritishGeological Survey, 2010).

1.2.6.1 Carboniferous rocks

The Carboniferous Pennine Coal Measures Group is present north of Allerdale from Workingtonalong the coast towards Carlisle. It is part of the exclusion area because "although coal seams to froma small part of the total thickness of the group, typically less than 10%, their presence has made thisgroup of primary economic importance (British Geological Survey, 2010).

1.2.6.2 Permian, Jurassic and Triassic rocks

The Sherwood Sandstone group is present in different formations around West Cumbria: Ormskirk Sandstone formation, Calder Sandstone formation and St Bees Sandstone formation . The SherwoodSandstone group is the primary aquifer in the area and needs particular attention to ensure no radiationwill contaminate potential exploitable groundwater resources that are currently exploited or could beexploited in the future (British Geological Survey, 2010).The sandstone formation is also "the main reservoir for oil and gas in the Irish Sea" (Jackson et al.,1995) and has the greatest potential for these resources so this needs to be part of the exclusion area.

1.2.6.3 Ordovician rocks

The Ordovician Skiddaw group are predominant in the northern part of the Lake District and aresuitable for hosting a geological disposal facility as they consist of clayey material of lowpermeability, a material already used in other geological disposal facilities such as in Sweden andFinland. However this Skiddaw group sits below the Lake District National park region, which is anatural domain that needs to be preserved.The Borrowdale and Eycott Volcanic group which are also of Ordovician age consist of Andesiticlavas and sills and pyroclastic and volcaniclastic rocks (British Geological Survey, 2010). These liemore predominantly in the central core region of the Lake District. The rock could be suitable for ageological disposal facility as pyroclastic deposits have porosity and permeability characteristics likethose of poorly sorted sediments; however, the pyroclastic material might become welded and almostimper meable. (United States Geological Survey, Unknown)

Waste

Water

flow

West East

Figure 2- Water flow in Cumbria (Smythe, 2010)


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1.2.7 Conclusion

The high potential of exploitable natural resources (coal, oil and gas, aquifers and iron ore) imposesconstraints on the location of a possible underground facility in the partnership area. An exclusionarea has been developed from information provided by the British Geological Survey memoirs inorder to protect these potential beneficial natural resources from contamination by nuclear waste.

The Exclusion area map present in Appendix B illustrates the different natural resources present inCumbria that need to be protected. The Sherwood Sandstone Group main aquifer, The Pennine coalmeasures group and oil and gas activities are present. (British Geological Survey, 2010)

The large area of the National park in green only leaves a small portion of West Cumbria out of theExclusion area. The National park needs to be preserved of its landscape and so construction withinthe park is not an option, knowing the Lake District national park attracts millions of visitors to thearea every year (West Cumbria Managing Radioactive Waste Safely Partnership, 2012).

So even though the Lake District National park area is the only region that has suitable geology (fromsection 1.3.2 and 1.3.3), the natural aspect of the area protects it and the topography is not suitable.The mountainous relief terrain of the region around the Lake District makes it even harder to considerbuilding a surface facility.

1.3 Romney Marsh, Kent

1.3.1 Introduction

Romney Marsh is situated in the South East of England, approximately 13 km (DigiMap, 2012) fromthe existing Dungeness power stations.

1.3.2 Level of Experience within Nuclear Industry and Employment Benefits

In Romney Marsh, the presence of Dungeness power stations A and B means there is also localexpertise in area with regards to the nuclear industry. The Dungeness power stations have created alarge amount of jobs for the local population , accounting for 8% of the all employment in theRomney Marsh Area. (BBC News, 2012). Dungeness power station B is due to fully close in 2017and Dungeness power station A to close in 2018 or 2023 if granted an extension. (BBC News, 2012).The closure of this power station in the near future will increase unemployment in the region. It istherefore possible that should Romney Marsh be approved as a location, some of the job losses thatwould come about from the closure of the power stations could potentially be offset.

1.3.3 Transport LinksRomney Marsh is easily accessible by road. It is in close proximity to the M20 motorway, as well astwo nearby A-roads, the A259 and A2070.Lydd (London Ashford) Airport is also within 10km of thetown of New Romney.

Rail links to the area are present, with a local railway station that has a direct line to the Dungenesspower stations. However, it could be argued that an improvement to the railway links to the Northwould be required for Romney Marsh to be a feasible location. (Google Earth, 2012).

1.3.4 Natural Capital of the Area

The presence of protected land and any sites of special scientific interest could affect the decision onany of the potential locations. There are small areas of Romney Marsh that are marked as sites of scientific interest, as well as smaller areas marked as nature reserves (Natural England, Unknown).


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1.3.5 Community Opposition

Despite the opportunities this project could bring for the residents of Romney Marsh, there remainsstrong opposition to the idea due to the health and environmental hazards that a GDF can pose. Thisworry is heightened by the fact that Kent is particularly vulnerable to flooding.

This negative view on the proposal seems to be shared by Kent County council leader Paul Carter,who went on record saying that Kent County Council is totally opposed to initiating any process t hateven entertains the possibility of building a nuclear waste disposal site anywhere near or around Kent (Griffiths, 2012). He then went on to suggest a Countywide referendum should the idea be pushedthrough.

This view is shared with the majority of the local residents. A local poll showed that 63% (BBC News,2012) of the community are against the idea. This leaves little room for possibility of Romney Marshbeing chosen as the location for the facility, with the government reluctant to select a location againstthe wishes of the local community.

1.3.6 Geology1.3.6.1 Sub-surface Unsuitability Test

The government managing radioactive waste safely White Paper (Department for Environment Foodand Rural affairs, 2008) identifies a number of basic criteria that can be used to determine if the basicgeology of a proposed site is unsuitable to host a geological disposal facility. The derivedunsuitability criteria are summarized (table.1).

To be applied as anexclusion criteria

Reasons/Explanations andQualifying Comments

Present atRomney Marsh?

Coal Deposits Yes Intrusion risk to depth, only whenresource at


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The Romney Marsh area was tested, using the unsuitability criteria, and currently available geologicaldata for the area under consideration (Appendix C). The results of the test are summarized (table.1).

Six deep boreholes exist within the area surrounding Romney Marsh (Appendix C). These boreholesindicate that the predominant deposits in the depth range being considered as Kimmeridge Clayoverlying the Corrallian Beds and Oxford Clay. All of these deposits can generally be described as

sedimentary mudstones or siltstones.Kimmeridge Clay is known to generally contain significant quantities of Hydrocarbons (Gallois,2004). In the Romney Marsh area, however, no commercially significant hydrocarbon deposits havebeen reported or licensed (British Geological Society and Lake R.D, 1987) (Department forCommunities and Local Government, 2006) (Department for Energy and Climate Change, 2012).

The hydrogeology of the Romney Marsh area is described as being of limited potential for watersupply of uncertain quality (British Geological Society, 1977). The main source of water in the area isabove ground storage with reduced reliance on aquifers (British Geological Society and Lake R.D,1987). The permeability of deposits in the area is generally considered to be low with fissures actingas the main transport mechanism for flow (British Geological Society and Lake R.D, 1987).

The Romney Marsh area is not categorized as unsuitable based on the sub-surface criteria suggestedfor initial screening. It is therefore reasonable to conclude that a suitable sub-surface geologicalsetting could be found within the area to host a GDF.

1.3.6.2 Topography, Geomorphology and Flood Risk

Romney Marsh is a flat low-lying crescent shaped expanse that is generally below high tide level(Appendix C). (May & Hansom, 2003) suggest that the marsh formed due to a sandy bar formingacross a crescent shaped bay creating a lagoon that subsequently silted-up to form Romney Marsh. Tothe seaward side of the sandy bar a cuspate shingle foreland formed due to the prevailing eastwardcurrent transporting shingle from the Sussex coast. The cuspate foreland is constantly being eroded

and reshaped by the prevailing currents with the exact position of the coastline changing significantlyover relatively short time scales (fig.3). The environment agency currently assesses the majority of theRomney Marsh area to have a risk of flood of 1 in 75 years (Environment Agency, n.d.)

It has been demonstrated, through the safe construction and operation of the Dungeness nuclear powerstations, that it is possible to provide robust flood defences in the area. The current flood protectionstrategy is to replenish shingle, eroded from the south coast with shingle sourced from the north coastof the cuspate foreland (Environment Agency, 2010). The use of replenishment for the protection of the shoreline is under constant review. Estimates of the replenishment rate are in the order of 50,000m 3 per year with a year on year increase of approximately 880 m 3 /year (Maddrell et al., 1994).

Due to the topography and geomorphology of the Romney Marsh area a significant flood risk existsthat will continue to increase in severity with time. The safe operation of the Dungeness nuclearpower station demonstrates that safe and economical flood defences can be constructed in the area.Siting a GDF in the area would, however, require a larger scale more longer term flood defencescheme potentially permanently altering a coast line t hat is described as being of internationalimportance

(English Nature, Unknown).


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1.4 Selection of alternative site for geological disposal facility

Even though West Cumbria and Romney Marsh were two areas that were put forward for furtheranalysis from the stakeholders, it was felt necessary to consider other areas that could possibly host ageological disposal facility. This report will look at one other area in the UK that seems most suitablefor hosting a geological disposal facility. This area will then be compared to West Cumbria and Kentin a decision matrix table in order to identify the most suitable site that could host the geologicaldisposal facility.

The starting point in proposing an alternative suitable location for a geological disposal facility is torule out areas in the UK where it is unsuitable to dispose of nuclear waste. The remaining areas canthen be investigated to identify whether the site meets the geological requirements for establishing ageological disposal facility together with other factors.

The following criteria will be used to identify a site location for a repository in the UK: Locate site near running or closed down nuclear power stations. Site must not be located in an area which could significantly affect the surrounding natural

environment. Site must be distant from earthquake prone areas. Site must not be within a rock fault zone. Site must have an average spacing of 100m between adjacent faults in the rock. There must be relatively low stressed rocks. Subsurface rocks should have a high thermal conductivity.

The above factors are essential safety features for the location that will be selected for the repository(Olsson et al., 2009).

1.5 SizewellSizewell has been chosen as our alternative site and will be investigated in this report. It is located onthe Suffolk coast and is home to two separate Nuclear reactors with one in the process of beingdecommissioned, and a third being proposed. It is a small village otherwise known for its fishing andtourism.

Figure 3- Historic Coastline Contours (British Geological Society and Lake R.D, 1987)


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1.5.1 Community opposition

As Sizewell has not expressed an official interest in the search for a GDF, there is little informationavailable on the potential public opinion. Sizewell is already home to two nuclear reactors, and withanother one in the planning stages, a level of public opinion towards the nuclear industry can beascertained.

There are many groups set on shutting down the Sizewell plants, however most of the arguments forthis are to do with Nuclear power production itself and less to do with the Sizewell area. Every year agroup of protestors hold a camp near the Sizewell plant (Stop Nuclear Power, 2012). Thisdemonstration is designed to promote their views, and try to educate the local population on thedangers of Nuclear power. With the recent Fukushima disaster in Japan, and a recent study in France -(Shutdown Sizewell Campaign, Unknown) showing that children living in the vicinity of a Nuclearpower plant have a higher leukaemia incidence rate - the public are very worried about the dangers of Nuclear power.

1.5.2 Earthquake and fault zones

A map of geological fault zones in the UK as shown in figure 5 shows the North of England, Scotland,Wales, Southwest and West midlands as having a high frequency of fault zones as compared with theSouth East and East midlands.

The identification of fractures within the bedrock at an existing geological disposal facility in Swedenwas considered the biggest factor for long -term safety as it is essential to limit groundwater flow (Olsson et al., 2009).The effects earthquakes would have on altering the structure of bedrock was also considered to ensurelong term safety of the facility. Historic data of earthquakes in the United Kingdom were studied toensure that the future geological facility would not be close to any earthquake prone areas. Figure 4shows that earthquakes have historically occurred numerous times in the west as compared to the eastof the UK. This figure agrees with figure 5 which shows that the majority of the fault zones also lie inthis region. The South-East, North-East, East Scotland and Southwest Scotland have reduced

seismometer readings, making the South-East a suitable proposition for the location of the GDF.

Figure 5 Geological fault zonesin the UK (Esri, 2010)

Figure 4- Earthquake historyin the UK (British Geologicalsociety, Unknown)


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1.5.3 Topography

The topography of the area is also important when looking at the suitability of a geological disposalfacility. As mentioned previously in the report, the existing repository facilities around the world wereall constructed on a low relief terrain with little variation in the regional topography. The relief map of the United Kingdom in Appendix D illustrates the height level of land above water, clearly illustratingthe East midlands and South-East region as being the lowest relief terrains with little variation in thetopography. This region was also identified as suitable in the previous section when looking at faultzones and earthquakes.

1.5.4 Flooding

Andra, the agency in charge of the management for nuclear waste in France had identified thepotential for flooding as one of the main criteria in deciding the location of its underground repository.Appendix D illustrates the flood plain zones in England. The East-midlands flood plain zones aresignificant compared to the rest of the UK which has limited flooding warnings.

1.5.5 Transport

Sizewell, which is located on the coast, has a large shipping port located nearby at Harwich. There areno adequate road links currently to enable the movement of waste from the rest of the country toSizewell. There are however rail links nearby, but they do not currently service Sizewell. The nearestairfield is Bentwaters Royal Air Force Base just 18km (Google Earth, 2012) away by road. Again,significant investments would need to be made to facilitate the disposal of waste at this site.

1.5.6 Geology

The following table 2 from (Royal Haskoning, 2009) gives a description of the geology under theSizewell B in sequential and descending order. Sizewell B power plant is situated very close to thepotential geological disposal facility location in Sizewell.

Table 2- Geology of Sizewell B (Royal Haskoning, 2009)
http://www.virtualtenby.co.uk/airport.asp?PhoneNumber=Bentwaters%20Royal%20Air%20Force%20Basehttp://www.virtualtenby.co.uk/airport.asp?PhoneNumber=Bentwaters%20Royal%20Air%20Force%20Base


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The upper Chalk layer was found to be down to -150 m Ordnance Datum. The sequence of materialsbetween the upper chalk layer and the pre-permian rocks which are below are not known due limiteddata information. With limited geological data available from the British Geological Society, Deepboreholes at Harwich were analysed and indicated that the pre-permian rocks start at -400 m OD andextend down to a considerable depth. This is why it was chosen that our geological disposal facilitywould be down to -500 m in depth. (EDF Energy, 2011).

The report by produced by EDF also states that the Sizewell region lies within the Anglo -BrabantPlatform, a crustal block that has suffered only limited deformatio n in the past 450 million years (EDF Energy, 2011).

The major aquifer present at Sizewell is the confined Chalk group. The Chalk and Crag aquifers arecurrently assessed as poor (quantitative) with poor chemical quality (Department of Energy andClimate Change, 2010). The Sizewell area is not known to have any other suitable natural resourcesunderground (oil and gas, hydrocarbons, coal deposits). It is therefore reasonable to conclude that asuitable sub-surface geological setting could be found within the area to host a GDF.

1.6 Decision Making ProcedureThe site selection decision is based on a large range of interrelated and, in some cases disparate,considerations. The site selection method must, therefore, fairly compare these issues in an accurateand transparent manner.A comparative scoring system, based on a one to five scale with five being the best score, has beenemployed. Four critical considerations have been identified for the site selection; social issues,technical issues, proximity to transport infrastructure and cost. The score for each of the criticalconsiderations is to be based on the average score of a number of sub-categories. This system allows awide reaching assessment to be made of each of the critical considerations using a large range of datasources.

The site with the highest average score across these four critical considerations will be carried forwardto the design stage of the project.

1.6.1 Weightings

Weighting have been applied to each of the critical consideration to reflect their various importance inrelation to the construction of a GDF. The weightings, along with a rational for their derivation, ispresented (table.1)


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Table 3- Weightings for Decision Matrix table

1.6.2 Uncertainty

Where significant uncertainty exists in the allocation of a score to a sub criterion the weightingapplied to that sub criteria is to be reduced by 25%. This is to reduce the impact uncertainty has on thesite selection process.

1.6.3 Weighted Average Multipliers

Under the currently adopted procedure for selecting a site for a GDF two critical conditions must bemet; the area passes and initial geological screening and the local population accepts the proposals. Toaccount for these conditions in the decision-making process two multipliers will be applied to theweighted average for each of the sites.

If a site does not meet the initial geological screening criteria the weighted average score will bemultiplied by zero. If the site does meet the initial screening criteria the weighted average score is tobe multiplied by one. This is to prevent any sites that are inherently geologically unsuitable frombeing considered.

If a community has formally rejected a proposal for a GDF the final weighted average is to bemultiplied by zero. If a community has committed to the construction of a GDF the final weightedaverage is to be multiplied by one. If a community is still at the decision-making phase a multiplier tobe used that represents the probability that the community will accept the construction of a GDF.

CriticalConsideration

Weighting Rational

Social Issues 3 The population density of the UK necessitates that social issues be theprimary concern regarding the construction of a GDF since it is not feasibleto site the GDF in a sufficiently isolated location to avoid impacting oncommunities.

Technical Issues 1.5 It was felt that technical issues are subordinate to social issues in relation tothe construction of a GDF since Nirex identified numerous technicallyfeasible site but failed to implement a GDF due to a lack of consideration of social issues.

Proximity toTransportInfrastructure

1 Transporting waste safely to the GDF will be crucial to the success of theproject. It maybe desirable for numerous modes of transport to be employed.New transport infrastructure will also represent a significant cost andplanning obstacle to the project. It was, however felt that social andtechnical issues are more critical than those of waste transport.

Cost 0.75 Whilst it will be desirable to achieve value for money during theimplementation of the GDF the cost of the facility will not be critical to theimplementation of the GDF since it is considered a necessity under theMRWS white paper.


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Table 4 Decision matrix table

1.7 Decision Matrix

Allerdale Copeland RomneyMarsh

Sizewell

Criteria Score Weight Score Weight Score Weight Score Weight

Social

Level of previous experience withthe nuclear industry

4 3 5 3 3 3 4 3

Impact on tourism and communityimage

1 3 1 3 2 3 2 2.25

Natural capital of the area 1 3 2 3 2 3 3 3

Historical capital of the area 4 3 4 3 4 3 4 3

Population within the proposedarea

4 3 4 3 4 3 4 3

Weighted Average Score 8.4 9.6 9.0 10.2

Technical

Susceptibility of the area toflooding

5 1.5 5 1.5 1 1.5 4 1.5

Complexity of local topography 1 1.5 1 1.5 3 1.5 5 1.5

Reliance of local populations onsubsurface aquifers

1 1.5 1 1.5 3 1.5 4 1.5

Avenues for spoil storage anddisposal

2 1.5 2 1.5 4 1.125 3 1.5

Weighted Average Score 3.4 3.4 3.8 6

Transport

Proximity to existing waste stores 4 1 4 1 1 1 2 1

Proximity to rail infrastructure 5 1 4 1 4 1 3 1

Proximity to road infrastructure 1 1 1 1 4 1 2 1

Proximity to airports 3 1 1 1 4 1 4 1

Proximity to ports 2 1 1 1 4 1 4 1

Weighted Average Score 3 2.2 3.4 3

Cost

Facility cost 4 0.75 4 0.75 2 0.75 3 0.75

Weighted Average Cost CriteriaScore

3 3 1.5 2.25

AVERAGE SCORE FOREACH SET OF CRITERIA

4.5 4.6 4.4 5.4

Does the site pass the initialgeological screening criteria?

1 1 1 1

What is the likelihood of thelocal council accepting theconstruction of a GDF?

0.80 0.85 0 0.75

Final Score 3.6 3.91 0 4.1


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1.8 ConclusionFrom the decision matrix in section 1.7, the Sizewell location proves to be the best option for hostingthe future geological disposal facility. Sizewell received a Score of 4.1 which is higher than the scorereceived by Allerdale, Copeland and Romney Marsh.

The Allerdale and Copeland sites had a lower score mainly due to their geological formation and theimpact building the geological facility will have on tourism, with the Lake District National Park sitedin Cumbria. West Cumbria has inconsistencies in the geological subsurface rock formations. Thereare also major aquifers in the area that are currently being exploited, creating a large exclusion areaacross West Cumbria. The variation in height of the land surface also means that the topography isunsuitable. The area of West Cumbria was supposedly known to be - basement under sedimentarycover (BUSC) ideally suitable to store radioactive nuclear waste beneath, however recent analysishas shown there are multiple fault zones in the structure of the rock, deeming the area unsafe toconstruct a repository (Smythe, 2011) .

Romney Marsh was not chosen from the decision matrix mainly due to social and political factors.Section 1.3.5 show that 63% of the local population was against the idea of having a geologicaldisposal facility built in Kent. The social factor is a major issue as a geological disposal facility willonly be put in a location where the local community has volunteered, which is why the social issuehad a larger factor than any other issue in the decision matrix table. Romney Marsh is also prone toflooding which would require a substantial flood defence scheme to be conceived, adding to the costand complexity of the operation of building the geological disposal facility.

Sizewell is the location that has been chosen mainly due to its convenient location: It is in the South-East of England close to the sea, which is beneficial when looking at transport routes with being closeto a port. The major negative impact about Sizewell was the impact Sizewell would have on tourismin the area. However, Since Sizewell already hosts two nuclear power stations and is planning to buildanother one; we decided it would not alter the area significantly.


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2. Pre-Qualification exercise: Design Development2.1 IntroductionSizewell was chosen as a result of the preliminary assessment of the suitability of all the potential

sites that were proposed to host the geological disposal facility in Section 1 of the report. This sectionwill look at the design of the geological disposal facility in Sizewell, both for the underground andsurface facilities. An appropriate preliminary design and location for the surface facilities andunderground facilities will be developed. More detailed design drawings will follow and will beproduced on AutoCAD illustrating the civil/structural aspects of the GDF (surface facilities, wastetransport and reception, underground access). The waste quantities that will need to be disposed of inthe geological disposal facility will be explored in order to determine appropriate transport logisticsfor the operations of the facility. A Process flow Chart will be done for the emplacement of the wastefrom the port in Sizewell to the disposal area, as well as underground from the point of reception atthe base of the drift tunnel to the respective storage areas of the waste packages underground.

2.2 Waste Quantities for DisposalThe quantity of waste to be disposed of via geological disposal is a key consideration in the design of a geological disposal facility. In this section the data sources, assumptions and chosen wastequantities for the design of the geological disposal facility are presented. The reliability and accuracyof the chosen data sources is also explored.

2.2.1 Data Sources

The two primary data sources that are utilised to determine the quantity of waste to be stored in ageological disposal facility are: the 2010 UK radioactive waste inventory and the 2010 estimate of waste for geological disposal. These documents were prepared by the NDA and DECC and can beviewed as the most accurate publicly available sources of information regarding the quantities of radioactive waste within the UK. A third document, Nirex Report N/085 was also used as a source of supplementary information regarding the packaging of the waste to be disposed of.

2.2.1.1 The 2010 UK Radioactive Waste Inventory (UKRWI)

The UKWRI is the most recent inventory of what is currently classified as radioactive waste withinthe UK. The scope of the inventory extends to; HLW, ILW, LLW and some high volume low levelwaste (Department of Energy and Climate Change, 2011a). The inventory includes all currentlyexisting waste and also estimates for waste which will arise in the future as a result of currentprocesses. A break down is given of volumes of waste, volumes of waste when conditioned, volumesof waste when packaged and the resulting number of packages. Quantities of waste that exist and arepredicted to arise are also given on a site by site basis for all nuclear sites around the UK.

It is recognised that the UKWRI does not consider the following:

Waste that would require disposal via the GDF route arising from the construction of newnuclear power stations in the future

Spent fuel, Uranium and Plutonium is not currently considered waste and is therefore notincluded in the UKWRI

Overpacking of HLW waste canisters for final disposal

2.2.1.2 The 2010 Estimate of Waste for Geological Disposal (EWGD)

The EWGD provides a baseline inventory for geological disposal that is based on the UKWRI (see

section: 2.2.1.1). The baseline inventory differs from the UKWRI in the respect that it reports thevolume of radioactive waste and materials potentially destined for geological disposal (Department


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of Energy and Climate Change, 2011b). The scope of the report also extends to the estimation of quantities of spent fuel, plutonium and uranium that may need to be disposed of via the GDF route.

The EWGD also provides an upper inventory estimate. The upper inventory provides what isconsidered to be a realistic higher volume scenario (Department of Energy and Climate Change,2011b). This higher volume scenario includes disposal of waste arising from eight new build nuclear

reactors, the extended operation of existing nuclear reactors and the disposal of all defence uraniumand plutonium via the geological disposal route.

It is recognised that the EWGD has the following limitations:

Waste quantities arising from a nuclear new build program is inherently uncertain since theAP 1000 and EPR reactor types, being considered for construction in the UK (Department of Energy and Climate Change, 2011c), have never been tested

Package numbers for each type of waste are not specified The upper inventory is based on a large number of assumptions

2.2.1.3 Nirex Report N/085

Nirex report N/085 is an inventory of all radioactive waste in the UK, prepared by Nirex, in 2003. Thereport details the packaging methods for various types of waste including; spent fuel, uranium andplutonium. Nirex report N/085 will only be used to derive information regarding the packaging of various types of waste.

It is recognised that Nirex report N/085 has the following limitations:

Does not consider how waste arising from new build reactors will be packaged Details speculative methods for the packaging of uranium and plutonium that have not yet

been implemented

2.2.2 Assumptions

In the preparation of this report a number of assumptions regarding the quantities of waste be storedhave been made. The assumptions made are presented.

2.2.2.1 Nuclear New Build Program

It is assumed that the nuclear new build program involving the construction of eight new reactors willgo ahead. This assumption has been made in the context of shifting governmental policy towardsnuclear power (Department of Energy and Climate Change, 2012) (Harvey, 2012).

2.2.2.2 Spent Fuel, Uranium and Plutonium

It is assumed that all spent fuel will eventually be disposed of via the GDF route. In light of thenuclear new build program assumptions made (see section 2.2.2.1) the upper inventory as specified inthe EWGD is to be used as the final packaged volume.

The 2010 baseline inventory for quantities of uranium and plutonium as given in the EWGD are to beused. This assumption was made on the basis that the majority of extra waste considered in the upperinventory is a result of the disposal of uranium and plutonium associated with nuclear defenceactivities. It is not considered likely that nuclear defence activities will cease within the anticipatedtime frame of the GDF.

2.2.2.3 Waste Quantity Conversions

For planning purposes it is desirable to convert waste volumes to numbers of packages. Conversionfactors for LLW, ILW and HLW have been derived based on the information taken from table A1.2 of

the UKWRI (Appendix E). Conversion factors for spent fuel, uranium and plutonium have beenderived based on information taken from table 5, table 12 and table 14 of Nirex report N/085


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(Appendix F) The conversion factors were determined by dividing the packaged volume by thenumber of packages given in the relevant tables. The derived conversion factors to be used are:

LLW 70.76 m 3 /package ILW 2.17 m 3 /package HLW 0.196 m 3 /package Spent Fuel 1.7 m 3 /package Uranium 0.580/3.30 m 3 /package Plutonium 0.890 m 3 /package

It is recognised that these factors may vary for individual waste streams within each of the wastecategories. It is, however, hoped that these global averages will provide a sufficiently accurateestimate for planning purposes.

2.2.3 Waste Quantities for Design

The quantities of waste to be disposed of at the GDF are presented (Table.2).

Waste Type Final Packaged Volume forDisposal Including all Assumed

Future Arising (m 3)

ConversionFactor

(m 3/package)

Total Number of WastePackages

LLW 150,000 70.76 2150

ILW 786,000 2.17 365,000

HLW 12,000 0.196 61,500

Spent Fuel 22,200 1.70 13,100

Uranium(1) 106,000 0.580/3.30 183,000/32,100

Plutonium 7,820 0.890 8,790

Table 5 - Final Packaged Waste Volume for Geological Disposal Considering All Future Waste Arisingand Corresponding Package Numbers

Note 1: It is not currently known how Uranium will be packaged for transport and disposal. Two methods have beensuggested (Nirex, 2003), utilising the 500 litre drums and 3m 3 boxes. For planning purposes both methods were considered

2.2.4 Waste Locations for Design In order to determine the logistics of transporting waste to the GDF it is necessary to determine thedistribution of radioactive waste around the UK.

A spread sheet (Appendix G) was developed to determine the distribution of waste at various sitesaround the country. The basis of the spreadsheet was the UKWRI breakdown of waste quantities foreach site around the UK (Appendix H). It was assumed that future LLW, ILW and HLW, notconsidered in the UKWRI, would be distributed around the UK in the same proportions as currentwaste.

It is recommended that spent fuel, uranium and plutonium by conditioned and packaged at Sellafield.This recommendation was made on the basis that Sellafield already handles the reprocessing of spentfuel and therefore has the appropriate infrastructure. On this basis it is assumed that all spent fuel,uranium and plutonium must be transported from Sellafield to the GDF.


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2.3 Transportation of Waste to Site

2.3.1 Modes of Transport

As set out by the NDA (Nuclear Decomissioning Authority, 2010), there are three approved modes of transport that can be used to transfer nuclear waste to the chosen site at Sizewell. The approved modesof transport are rail, road and sea. Each method of transport has advantages and disadvantages, thestrength of which will depend on the type and length of journey, and the amount of safety issuesregarding the waste which is being transported.

2.3.1.1 Transport by Sea

Sea transport is the most desirable method for transporting the nuclear waste, as it has been usedsuccessfully and safely worldwide for over 30 years (Nuclear Decomissioning Authority, 2010)

One of the main benefits is the safety of the method of transport, as it will reduce the proximity of thewaste to the human population.

However, due to the level of handling required to allow ship transportation, it will be consideredunfeasible to use this method unless the distance from the waste-producing site to the waste storagesite is significant, and there is a large amount of waste to be transported. When these two conditionsare satisfied, and the waste-producing site is situated within a reasonable distance to a port, seatransport will be selected as the method to transfer waste.

2.3.1.2 Transport by Rail

Rail is the second most desirable method of transport for transferring the waste. It is considered arelatively safe mode of transport, although the waste is rarely kept away from the human population.

The advantage of using the rail network for the transport of waste is that it requires significantly lesshandling in order to load and unload the train. It may still be feasible to transport smaller amounts of waste to the storage site, even over a larger distance. If there is no local or on-site port at the waste-producing site, rail will be chosen as the mode of transport. If there is no close or on-site railwaystation, the feasibility of the construction of a station will be considered, depending on the volume andnature of the waste produced at the site in question.

2.3.1.3 Transport by Road

Road transport has been identified as the least favourable mode of transport to be used for the transferof nuclear waste to the Sizewell site. It is seen as the least safe method, mainly due to the level of human influence that impacts upon each journey. Due to the safety issues involved with road transport,there are significant speed and routing restrictions for the use of this method of transport. It isestimated that around 45% of transport packages are likely to be too heavy for the use of roadtransport (Nuclear Decomissioning Authority, 2010).

It is clear that some level of road transport will be required particularly for sites producing relativelylow volumes of waste. Where there is no onsite railway or port facility it may be desirable to transportwaste to nearby rail or port facilities by road. Road transport is also a feasible option for short

journeys; however, it is unlikely that any waste producing sites will be sufficiently close to Sizewellfor this to be viable.

2.3.2 Options for Transport

For some waste-producing sites, more than one mode might be combined to create the most efficienttransport route to the storage facility at Sizewell. The five combinations of modes that can be used areset out by the NDA as the following; (Nuclear Decomissioning Authority, 2012)


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2.3.2.1 Option 1

Option 1 uses only rail transport to transfer waste. This option is only available for waste-producingsites with an on-site railway station.

2.3.2.2 Option 2

Option 2 again uses rail transport to transfer waste, but this option is for sites that do not have an on-site railway station, and so requires the use of HGVs vehicles and other road vehicles to get the wasteto the railway network.

2.3.2.3 Option 3

Option 3 uses only road transport to transfer the waste to the GDF site. This option is available for allsites.

2.3.2.4 Option 4

Option 4 involves transport by sea. It is assumed that either the waste-producing site has an on-site orlocal port, and that rail transport will be used to and from sites where required.

2.3.2.5 Option 5

Option 5 again involves the use of transport by sea, with the use of road transport to and from sites asrequired.

2.3.2.6 Transport Option Preference Hierarchy

Options 4 and 5 have been chosen as the most desirable options. Option 4 will be selected for any sitewith an existing onsite port. If a sufficiently large port exists within the locality of the wasteproducing site option 5 will be selected. Where no onsite or nearby port exists, options 1 or 2 will bechosen since rail transport has been identified as being lower risk than road transport. Option 3 willonly be chosen when no other options are feasible since it is not possible to transport all packages byroad and is also identified as the highest risk method of transport.

2.3.3 Selection of Modes of Transport for Existing Sites

A total of 38 waste producing sites have been considered in the design waste quantity (see section2.2.4 waste locations for design). Only sites producing significant quantities of waste destined forgeological disposal will be considered for the purpose of this report. A site producing significantquantities of waste was deemed to be any site that the UKWRI reports as having a combined total of over 1000 packages (Appendix G Distribution of Waste Spreadsheet).

The desired transport method for each of the sites producing significant quantities of waste has beendetermined based on the transport option preference hierarchy identified (Table.1).

Site Selected Option Justification

AWE Aldermaston 2 The site it too far from the coast for option 4 or 5 to be practical. No onsite rail link exists necessitating HGV transport to the nearby rail link inbasingstoke.

Berkeley 2 No local port means option 2 is the most viable transport mode forBerkeley.

Bradwell 2 As Bradwell is so close to Sizewell, it would not be justified to use seatransport, so option 2 is the most viable.

Calder Hall 4 Calder Hall is on the Sellafield site and can therefore utilize the onsiteport to be constructed at Sellafield


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Capenhurst 1 The onsite rail station at Capenhurst makes all rail transport the mostdesirable option.

Dounreay 4 It is recommended that an onsite port be constructed to enable option 4for the transport of waste to the GDF

Dungeness 5 As Dungeness is near to the coast, option 5 is appropriate, with a

number of local ports available, including Dover.

Hartlepool 5 Option 5 can be used for Hartlepool, with local but not on-site portsavailable.

Heysham 5 Option 5 can also be used for Heysham, with local ports available.

Hinkley Point 2 There is no on site railway terminal, and no local port. Option 2 is theselected mode of transport for Hinkley Point.

Hunterston 4 An onsite port exists at the Hunterston site enabling option 4

LLWR Drigg 5 Option 5 can be used for the LLWR in Cumbria, via the proposed onsite port at Sellafield.

Oldbury 2 The lack of an on-site port or rail terminal at the Oldbury power station

means that option 2 is the most viable transport option for this site.Sellafield 4 Option 4 will be used for transport from the Sellafield site with an on-

site port proposed for construction.

Sizewell 3 As the Sizewell site is so close to the GDF, option 3 is a suitabletransport mode.

Torness 4 An onsite port exists at Torness making option 4 possible

Trawsfynydd 3 Trawsfynydd nuclear power station is in an extremely remote locationwith no nearby ports and only local rail lines. Option 3 is the onlyfeasible option without the construction of extensive new localinfrastructure.

Windscale 4 Windscale is on the Sellafield site and can therefore utilize the onsite

port to be constructed at SellafieldWinfrith 2 Waste can be transported by road to the nearby Weymouth to London

Waterloo rail line

Wylfa 4 An onsite port exists at the Wylfa site. Option 4 is therefore viable.

Table 6 - Selection of Transport Methods for Major Waste Producing Sites

2.3.4 Logistics and Delivery Rates

The main challenge of siting a GDF in the east of England is facilitating the safe transportation of thelarge volume of waste arising at Sellafield to the GDF. A study has been undertaken to determine thelogistics of this operation.

The preferred transport option between Sellafield and the GDF has been identified as transport option4 (section 2.3.2.4). Barrow-in-Furness is currently utilised as a port for waste being shipped overseasfrom Sellafield (Nuclear Decomissioning Authority, 2010). In light of the quantity of waste to betransferred to the GDF from Sellafield it was not felt to be sustainable to continue the use of Barrow-in-Furness. It was concluded that the construction of a port on the Sellafield site would lower theoverall risk of the transport process and minimise the exposure of local residents to waste. It is alsointended for an onsite port to be constructed at the GDF.

2.3.4.1 Transport Vessels

The international maritime organisation requires that nuclear waste be transported using vessels thatconform to the International Code for the Safe Carriage of Packaged Irradiated Nuclear Fuel,

Plutonium and High-Level Radioactive Wastes on Board Ships (International Maritime Organisation,2011). Pacific Nuclear Transport Limited (PNTL) currently operates a fleet of ships that conform to


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these regulations (Appendix I). The specification assumed for ships transporting waste betweenSellafield and the GDF (table 4) is based on those of the ships operated by PNTL.

Table 7 - Specification of Waste Transport Ships

2.3.4.2 Accident Rates and Risk Assessment

It has been reported (International Atomic Energy Agency, 2001) that even if a transport ship isinvolved in a collision the risk of nuclear material being released into the environment is negligiblylow. This is due to the extensive safety measures in place to prevent the release of hazardous material.

It was, however, felt that even if a relatively modest incident were to occur the public perception of such an incident and the associated delays could have a serious impact on the project. A probabilisticrisk assessment was conducted to determine the total risk of an incident occurring during the course asingle journey from Sellafield to the GDF (Appendix J Transport Risk Calcs). It was found that theprobability of an incident occurring per journey is 4.0x10 -4.

The delay to the transport process associated with an incident occurring is difficult to determine sinceit would depend on the severity and cause of the incident. To estimate the potential delay to theproject a major national project, delayed due to an accident, was sought. The delay to the space shuttleprogram following the challenger disaster was found to be 3 years (National Geographic, 2012). Itwas felt that an incident involving the transport of nuclear waste would have a similar impact on thenational psyche and require an enquiry of a similar length prior to reinitiating the process.

2.3.4.3 Summary of Logistics

It is anticipated that the time frame for waste to be emplaced within the GDF will be approximately150 years. The logistics of delivering waste to the site was calculated (Appendix K logistics calcs)based on this timeframe. Delays to the transport program resulting from incidents during transportwere also included in the logistics calculations. The main outcomes of the logistics study arepresented (table.5)

Table 8 - Summary of Transport Logistics

Length 110 meters

Breadth 20 meters

Draft 7 meters

Speed 14 knots

Max Number of Packages 20

Deadweight 5000 tonnes

Average Number of Transport Vessels Arriving at the GDF per Week 4.5

Size of Transport Vessel Fleet 6

Maximum Number of Packages Delivered Per Week 92

Anticipated Number of Incidents During Waste Transport 12


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2.4 Design specification: Development of the brief

2.4.1 Surface Facilities Need multiple Access underground via three vertical shafts and a drift tunnel

Need separation of ventilation systems from operations Need Security of access in case of a default in shafts

Operational Requirements:

o Separate waste handling lines for ILW and HLW packages.

o LLW and ILW inspection, monitoring and emplacing process to be designed to

handle as maximum delivery rate of 92 packages per week (see section 2.3.4.3)

o HLW inspection, monitoring and emplacing process to be designed to handle a

maximum delivery rate of 9 packages per week.

o A facility management centre to control both surface and subsurface activities with an

unobstructed view of the entire site.

o Security installations at all entrances

o Medical services and Health Building

o Food Service Building

o Training Building

o Visitor Centre

o On site power generation system with redundancy

o Fire house

o Access Underground:

Two Vertical Shafts for Ventilation

One Vertical shaft for emergency (people access or could transport waste if

one of the other tunnels cannot be used)

2 drift tunnels to Transport waste underground

(Sorenson et al., 2008) (Nuclear Decomissioning authority, 2010) (Andra,

2010)

Construction Support Facilities: Building requirements

o Construction Management Offices

o Rock Crushing Facility (Including Crusher and Storage Area for Rock to be Crushed)

o Connection between dispatch rail siding and rock crusher to transport material off site

o Excavated Rock Stockpile: Minimum Capacity of 3500m 3 of Enclosed Storage Space

o Fire/Rescue Station: Full Fire Station (with support for minimum of 3 engines) and

Mines Rescue Capability

o Buffer Material Plant: Produces buffer material for sealing subsurface storage areas


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o Workshops and Storage areas for construction plant and materials.

o Access Underground:

2 Vertical shafts for ventilation and emergency use

1 Drift tunnel for movement of plant and materials between surface and

subsurface

2.4.2 Underground Operational Requirements Develop design for low strength sedimentary rock (Chalk)

Provide storage for 150,000m 3 LLW (See Section: 2.2.3)

Provide storage for 786,000m 3 ILW (See Section: 2.2.3)

Provide storage for 12,000m 3 HLW (See Section: 2.2.3)

Provide storage for 22,200m 3 SF (See Section 2.2.3)

Design facility with the capability to expand tunnels for future storage use.

Ensure minimum separation of 500m between different types of waste.

Facility must not hinder nearby Sites of Scientific Interest. (Sorenson et al., 2008)

2.4.3 Waste Transport and Infrastructure Requirements Provide a port to accommodate four transport ships. (Approximate dimensions 110m long x

20m wide with min operating depth of 15 meters)

Provide unloading and transfer system capable of unloading transport ships within 6 hours of

arrival (based on assumed cargo of 18 packages per ship)

Provide rail spur to connect GDF directly with Leiston rail spur

Provide eight 240 meter long sidings to accommodate trains arriving and awaiting dispatch

Provide parking space for 26 unloaded HGVs

Provide space for 2 HGVs carrying waste packages awaiting approval to enter site.

Provide unloading facility for one HGV

Provide parking for 100 staff

Provide parking for 20 visitors to the site

2.4.4 Safety Provide a robust flood defence scheme for the site

Ensure all above ground building designs are compatible with seismic design guidance

Minimise the exposure of local residents to waste packages.

Provide multiple emergency access routes by road to the site.


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2.4.5 Sustainability and environmental impacts Mitigate the visual impact of the surface facilities on the local communities of Sizewell and

Leiston

Optimise building designs to reduce whole life energy use, embodied carbon and use of non-

renewable resources

Surface facilities will not encroach on areas that have statutory protection (SSSIs and SACs)

Maximise opportunities to maintain and improve local biodiversity.

Ensure access to local community services is unaffected during and after construction

Maximise the onsite use/reuse of excavated spoil to minimise the quantities that must be

transported away from the site

2.5 Preliminary Design of Proposed Sites in Sizewell

2.5.1 Introduction

Sizewell has been selected as the most favourable area for the siting of a GDF. The surface facilitiesrepresent a relatively small part of the overall GDF construction project. It will, however, be thesurface facilities that project the image of the GDF to local communities and those visiting the site.The selection of an appropriate site and design for the surface facilities is therefore a critical designconsideration.

The area around the Sizewell nuclear power station is relatively constrained. Areas of environmentally protected land and areas already scheduled for the development of Sizewell C are notsuitable for the siting of the GDF surface facilities (fig 6: overview map showing potential sites).Siting the surface facilities to cause minimum disruption to the local communities of Leiston,Eastbridge and Sizewell was also a key consideration.

Two potentially suitable sites were identified for the siting of the surface facilities (fig 6: overviewmap showing potential sites). The constraints and opportunities associated with siting the surfacefacilities of the GDF on either of these two sites are explored. Preliminary designs for the surfacefacility layout are presented and analysed to determine the most promising site and layout for furtherdevelopment.


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2.5.2 Location of Sites

SITE 1

SITE 2

Figure 6- Map of Sizewell


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2.5.3 Constraints and Opportunities

2.5.3.1 Site 1

Site 1 is located to the North of the existing Nuclear reactors and extends to the edge of MinsmereLevel (RSPB Nature Reserve). The site totals the required area of 1km 2, consisting mainly of farmland, a small area of woodland (0.1km 2 (Google Earth, 2012)) and one residential property (AshWood Cottages). Located to the East of the site is a large area of land sitting on a flood plain. To theNorth of the site a farmhouse is situated close to the boundary, two residential properties and a smalllane (Sandings Lane) to the West, and to the South is woodland and one residential property. The siteis located over 2.5km away from Leiston centre (Google Earth, 2012).

Locating the GDF within Site 1 would require the destruction of 0.1km 2 of woodland, the purchasingof 1 residential property, and potential for disruption to another 4. Excluding the aforementionedproperties the surrounds would be largely unaffected. The site gently slopes from West to Eaststarting at 15m AOD falling to 9m AOD, this shouldnt present too much of a challenge for the sitelayout.

Road access to the site would either be from the West of the site via Sandings lane (which would needwidening to cope with the traffic), or via the South of the site as an extension of the current accessroad to Sizewell A, B and ostensibly C. the site is situated approximately 1km away from the coastwhich would mean waste could feasibly be transported ashore. To connect the site by rail, anextension to the Leiston spur would require roughly 2km of new track to be laid.

Extra site space could be found by extending the site to the North, encompassing Lower Abby Farmwhich is a Grade II listed building, and to the south where Sizewell C temporary works is to besituated. Lowe Abby Farm house could potentially be incorporated into the site without the need todemolish it. Site offices will be needed, and could provide the site with a touch of traditional character.

2.5.3.2 Site 2

Site 2 is located to the south west of the existing Sizewell A reactor. The site 2 has a total area of approximately 1-kilometer square. Sizewell Gap to the South, Lovers Lane to the West and SandyLane to the North border site 2. The Sizewell Belts SSSI borders the site to the Northeast. Themajority of site 2 is currently used for agriculture.

Approximately 20% of the site is covered by existing flora. It will prove necessary to remove the twoareas of flora to the north of the site. These areas of flora are generally poorly developed and notunder any specific protection. It is not anticipated that the tree line bordering the south of the site willneed to be removed. It may prove beneficial to extend and develop this tree line to mitigate the visualimpact of the site on the community of Leiston.

It is only anticipated that a single private property within the area of Site 2 would need to bepurchased as a result of the construction of the surface facilities. Thirteen private properties share aborder with the site. The five properties on Sandy Lane will be the most severely affected.Site 2 slopes from the so

Geological Disposal Facility Design

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