ITERITER EDA DOCUMENTATION SERIES No. 24International Thermonuclear Experimental Reactor(ITER)Engineering Design Activities(EDA)ITER TECHNICAL BASISINTERNATIONAL ATOMIC ENERGY AGENCY, VIENNA, 2002ITER TECHNICAL BASISIAEA, VIENNA, 2002IAEA/ITER EDA/DS/24Printed by the IAEA in ViennaJanuary 2002FOREWORDDevelopmentofnuclearfusionasapracticalenergysourcecouldprovidegreat benefits.This fact has been widely recognized and fusion research has enjoyeda high level of international co-operation.Since early in its history, the InternationalAtomicEnergyAgencyhasactivelypromotedtheinternationalexchangeoffusioninformation.Inthiscontext,theIAEArespondedin1986tocallsatsummitlevelforexpansionofinternationalco-operationinfusionenergydevelopment.AttheinvitationoftheDirectorGeneraltherewasaseriesofmeetingsinViennaduring1987,atwhichrepresentativesoftheworld'sfourmajorfusionprogrammesdevelopedadetailedproposalforco-operationontheInternationalThermonuclearExperimentalReactor(ITER)ConceptualDesignActivities(CDA).TheDirectorGeneraltheninvitedeachinterestedPartytoco-operateintheCDAinaccordancewith the Terms of Reference that had been worked out.All four Parties accepted thisinvitation.TheITERCDA,undertheauspicesoftheIAEA,beganinApril1988andweresuccessfullycompletedinDecember1990.Theinformationproducedwithinthe CDA has been made available for the ITER Parties and IAEA Member States touse either in their own programmes or as part of an international collaboration.AftercompletingtheCDA,theITERPartiesenteredintoaseriesofconsultationsonhowITERshouldproceedfurther,resultinginthesigningoftheITEREDA(EngineeringDesignActivities)AgreementonJuly21,1992inWashington by representatives of the four Parties.The Agreement entered into forceuponsignatureoftheParties,withtheEDAconductedundertheauspicesoftheIAEA.As the original six-year EDA Agreement approached a successful conclusion,thePartiesenteredintoaseriesofconsultationsonhowfuturestepscouldbetakentowarddecisionsonconstruction.AprovisionalunderstandingwasreachedthattheEDA Agreement should be extended by three years to enable the Parties to completetheir preparations for possible construction decisions.By the time of the expiration oftheoriginalEDAAgreement,theEU,JAandRFPartieshadagreedtoextendtheAgreementwhiletheUSParty,complyingwithCongressionalviews,didnotparticipate beyond an orderly close out activity ending in September, 1999.TheITEREngineeringDesignActivitiesweresuccessfullyterminatedon21July 2001.As part of its support of ITER, the IAEA is pleased to publish the documentssummarizingtheresultsoftheEngineeringDesignActivities.Togetherwiththetwenty-three previous volumes in the ITER EDA Documentation Series, on:- ITER EDA Agreement and Protocol 1 (DS/1)- Relevant Documents Initiating the EDA (DS/2)- ITER Council Proceedings: 1992 (DS/3)- ITER Council Proceedings: 1993 (DS/4)- ITER EDA Agreement and Protocol 2 (DS/5)- ITER Council Proceedings: 1994 (DS/6)- Technical Basis for the ITER Interim Design Report, Cost Review and Safety Analysis (DS/7)- ITER Council Proceedings: 1995 (DS/8)- ITER Interim Design Report Package and Relevant Documents (DS/9)-ITER Interim Design Report Package Documents (DS/10)-ITER Council Proceedings: 1996 (DS/11)-ITER Council Proceedings:1997 (DS/12)-Technical Basis for the ITER Detailed Design Report Cost Review and Safety Analysis (DDR) (DS/13)-ITER Final Design Report, Cost Review and Safety Analysis (FDR) and Relevant Documents (DS/14)-ITER Council Proceedings: 1998 (DS/15)-Technical Basis for the ITER Final Design Report, Cost Review and Safety Analysis (FDR) (DS/16)-ITER Council Proceedings: 1999 (DS/17)-ITER-FEAT Outline Design Report (DS/18)-Technical Basis for the ITER-FEAT Outline Design (DS/19)-ITER Council Proceedings: 2000 (DS/20)-Final Report of the ITER EDA (DS/21)-Summary of the ITER Final Design Report (DS/22)-ITER Council Proceedings: 2001 (DS/23)this document presents essential information on the evolution of the ITER EDA. CONTENTS PLANT DESIGN SPECIFICATION PLANT DESCRIPTION DOCUMENT INTRODUCTIONFollowing on from the Final Report of the EDA (DS/21), and the Summary ofthe ITER Final Design Report (DS/22), the technical basis gives further details of thedesignofITER.Itisintwoparts.Thefirst,thePlantDesignSpecification,summarises the main constraints on the plant design and operation from the viewpointofengineeringandphysicsassumptions,compliancewithsafetyregulations,andsitingrequirementsandassumptions.Thesecond,thePlantDescriptionDocument,describes the physics performance and engineering characteristics of the plant design,illustratesthepotentialoperationalconsequencesforthelocalityofagenericsite,givestheconstruction,commissioning,exploitationanddecommissioningschedule,and reports the estimated lifetime costing based on data from the industry of the EDAParties.ITER Technical Basis G A0 SP 2 01-06-01 R2.0Plant Design Specification(PDS)ITER Technical BasisG A0 SP 2 01-06-01 R2.0Plant Design Specification Page 3Table of Contents1 Programmatic Objective..................................................................................................52 Technical Objectives and their Interpretation..............................................................52.1 Interpretation..............................................................................................................52.2 Scope of the EDA ...................................................................................................... 112.3 Design Principles....................................................................................................... 123 Safety Principles and Criteria.......................................................................................123.1 Safety Objectives....................................................................................................... 133.2 Safety Principles........................................................................................................ 133.2.1 'As Low as Reasonably Achievable' .......................................................................... 133.2.2 Defence-in-Depth.................................................................................................. 133.2.3 Passive Safety....................................................................................................... 143.2.4 Consideration of ITERs Safety Characteristics........................................................... 143.2.5 Review and Assessment.......................................................................................... 153.3 Safety and Environmental Criteria ........................................................................... 153.4 Elements of the Generic Safety Approach................................................................. 163.4.1 Confinement......................................................................................................... 173.4.2 Component Classification ....................................................................................... 173.4.3 Earthquake........................................................................................................... 183.4.4 Environmental Qualification.................................................................................... 183.4.5 Fire..................................................................................................................... 183.4.6 Decommissioning and Waste................................................................................... 183.4.7 Effluents.............................................................................................................. 193.4.8 Radiation Protection............................................................................................... 193.4.9 Hazardous Materials .............................................................................................. 213.4.10 Conventional Hazards ............................................................................................ 213.4.11 Security and Proliferation........................................................................................ 214 Site Requirements & Assumptions ...............................................................................22Introduction.......................................................................................................................... 22I Principles for Site Requirements and Site Design Assumptions..................................... 22II Site Requirements ......................................................................................................... 23A. Land........................................................................................................................... 231. Land Area................................................................................................................ 232. Geotechnical Characteristics........................................................................................ 243. Water Supply............................................................................................................ 244. Sanitary and Industrial Sewage .................................................................................... 24B. Heat Sink..................................................................................................................... 25C. Energy and Electrical Power............................................................................................ 25D. Transport and Shipping.................................................................................................. 251. Maximum Size of Components to be Shipped................................................................. 252. Maximum Weight of Shipments................................................................................... 27E. External Hazards and Accident Initiators............................................................................ 27F. Infrastructure................................................................................................................ 27G. Regulations and Decommissioning................................................................................... 27III Site Design Assumptions ........................................................................................... 27A. Land........................................................................................................................... 271. Land Area................................................................................................................ 272. Topography.............................................................................................................. 283. Geotechnical Characteristics........................................................................................ 284. Hydrological Characteristics........................................................................................ 285. Seismic Characteristics............................................................................................... 286. Meteorological Characteristics..................................................................................... 29ITER Technical BasisG A0 SP 2 01-06-01 R2.0Plant Design Specification Page 4B. Heat Sink: Water Supply for the Heat Rejection System........................................................ 29C. Energy and Electrical Power............................................................................................ 301. Electrical Power Reliability during Operation ................................................................. 302. ITER Plant Pulsed Electrical Supply ............................................................................. 30D. Transport and Shipping.................................................................................................. 311. Highway Transport .................................................................................................... 312. Air Transport............................................................................................................ 313. Rail and Waterway Transport ...................................................................................... 31E. External Hazards and Accident Initiators............................................................................ 311. External Hazards....................................................................................................... 312. External (Natural) Accident Initiators............................................................................ 32F. Infrastructure................................................................................................................ 321. Industrial ................................................................................................................. 322. Workforce................................................................................................................ 333. Socioeconomic Infrastructure ...................................................................................... 34G. Regulations and Decommissioning................................................................................... 341. General Decommissioning .......................................................................................... 342. ITER Plant "Deactivation" Scope of Work ..................................................................... 35H. Construction Phase........................................................................................................ 35ITER Technical BasisG A0 SP 2 01-06-01 R2.0Plant Design Specification Page 51 Programmatic ObjectiveAccordingtotheITEREDAAgreement,"theoverallprogrammaticobjectiveofITERistodemonstratethescientificandtechnologicalfeasibilityoffusionenergyforpeacefulpurposes."2 Technical Objectives and their InterpretationFollowingtherecommendationsofaSpecialWorkingGroup(SWG)[seeverbatimquotefromthereportinthepaneloverleaf],theITERCouncilaskedtheDirector"tocontinueeffortswithhighprioritytowardestablishing,withtheassistanceoftheJointCentralTeam(JCT) and Home Teams (HTs), option(s) of minimum cost aimed at a target of approximately50%ofthedirectcapitalcostofthe[1998ITER]designwithreduceddetailedtechnicalobjectives,whichwouldstillsatisfytheoverallprogrammaticobjectiveofITER.Theworkshouldfollowtheadoptedtechnicalguidelinesandmakethemostcost-effectiveuseofexisting design solutions and their associated R&D."2.1 InterpretationThese technical objectives have been interpreted as follows: Theexistingphysicsdatabaseleadstoconstraininginductiveperformanceinthefollowing way:- H-mode scaling law as recommended by the Confinement Expert Group;- normalized beta, N = aB/I < 2.5 (a = plasma minor radius (m), B = toroidal fieldat the plasma geometric centre (T), I = plasma current (MA);- normalizeddensity,n/nGW =na2/I < 1.0 (n = electron density, nGW = Greenwalddensity);- safety factor at the 95% flux surface, q95 ~ 3;- impurity factor Zeff2.0;- a well controlled, divertor plasma configuration. The ITER design shall incorporate features that permit testing to:- demonstrate the reliability of nuclear components;- furnishdataforcomparingcandidateconceptsfornuclearcomponentsandtoprovide a basis of extrapolation;- demonstrate tritium breeding;- provide fusion materials testing data. Maintainabilityfeatureswillbeincorporatedintothedesigninsuchawayastoachievethemissionreliability,operationalavailability,andscheduledmaintenancerequirements.Inparticular,remotehandling(RH)featureswillbedesignedandqualifiedthatpermittimelyinsertionandremovalofin-vesselcomponents,testblanket modules and other test articles.ITER Technical BasisG A0 SP 2 01-06-01 R2.0Plant Design Specification Page 6Plasma PerformanceThe device should: achieve extended burn in inductively driven plasmas with the ratio of fusion power to auxiliary heatingpower of at least 10 for a range of operating scenarios and with a duration sufficient to achievestationary conditions on the timescales characteristic of plasma processes. aim at demonstrating steady-state operation using non-inductive current drive with the ratio of fusionpower to input power for current drive of at least 5.In addition, the possibility of controlled ignition should not be precluded.Engineering Performance and TestingThe device should: demonstrate the availability and integration of technologies essential for a fusion reactor (such assuperconducting magnets and remote maintenance); test components for a future reactor (such as systems to exhaust power and particles from the plasma); Test tritium breeding module concepts that would lead in a future reactor to tritium self-sufficiency, theextraction of high grade heat, and electricity production.Design Requirements Engineering choices and design solutions should be adopted which implement the above performancerequirements andmake maximum appropriate use of existing R&D database (technology and physics)developed for ITER. The choice of machine parameters should be consistent with margins that give confidence in achievingthe required plasma and engineering performance in accordance with physics design rules documentedand agreed upon by the ITER Physics Expert Groups. The design should be capable of supporting advanced modes of plasma operation under investigation inexisting experiments, and should permit a wide operating parameter space to allow for optimisingplasma performance. The design should be confirmed by the scientific and technological database available at the end of theEDA. In order to satisfy the above plasma performance requirements an inductive flat-top capability duringburn of 300 to 500 s, under nominal operating conditions, should be provided. In order to limit the fatigue of components, operation should be limited to a few 10s of thousands ofpulses In view of the goal of demonstrating steady-state operation using non-inductive current drive in reactor-relevant regimes, the machine design should be able to support equilibria with high bootstrap currentfraction and plasma heating dominated by alpha particles. To carry out nuclear and high heat flux component testing relevant to a future fusion reactor, theengineering requirements areAverage neutron flux 0.5 MW/m2Average neutron fluence 0.3 MWa/m2 The option for later installation of a tritium breeding blanket on the outboard of the device should not beprecluded. The engineering design choices should be made with the objective of achieving the minimum cost devicethat meets all the stated requirements.Operation RequirementsThe operation should address the issues of burning plasma, steady-state operation and improved modesof confinement, and testing of blanket modules. Burning plasma experiments will address confinement, stability, exhaust of helium ash, and impuritycontrol in plasmas dominated by alpha particle heating. Steady-state experiments will address issues of non-inductive current drive and other means for profileand burn control and for achieving improved modes of confinement and stability. Operating modes should be determined having sufficient reliability for nuclear testing.Provision shouldbe made for low-fluence functional tests of blanket modules to be conducted early in the experimentalprogramme.Higher fluence nuclear tests will be mainly dedicated to DEMO-relevant blanket modules inthe above flux and fluence conditions. In order to execute this program, the device is anticipated to operate over an approximately 20 yearperiod. Planning for operation must provide for an adequate tritium supply.It is assumed that there willbe an adequatesupply from external sources throughout the operational life.ITER Technical BasisG A0 SP 2 01-06-01 R2.0Plant Design Specification Page 7 Themechanicaldesignofthedeviceshallwithstandtheexpectedtemperatures,pressures,electromagneticfields,chemicalenvironment,andradiationenvironmentunder all projected operating conditions and assumed accident conditions. Prior to site selection, structural evaluation shall be in accordance with specific codesandstandardswhichareagreedamongthethreeParties.Ifnosuchcodesandstandardsexist,standardsorguidelinesestablishedbytheJCTshallbesurrogated.Thedesignmustnotprecludereadilyachievablemodificationstoincorporatealternate codes and standards, which may be required by the Host Party. The design shall facilitate decommissioning, and reduce occupational exposures, by:- use of modular components for easy dismantling;- segregating radioactive systems or components;- designing to avoid contamination or to allow easy decontamination;- selectionofconstructionmaterialstoreduceactivationproductsinmaterialssubject to irradiation. ITERshallhaveawastemanagementprogramthatminimiseswaste.ThetreatmentsystemsforradioactivewastesgeneratedinITERshallbedesignedtominimizedispersion of radioactive materials during all stages of handling.ITER systems shallbe designed to package radioactive waste in accordance with the requirements of thePartythatwillship,handleandinternthewaste,sothatnoadditionalhandlingorexposure is required by re-packaging. Delivery of components, systems and structures will be just in time to fulfil the needsof the experimental programme subject to the following limitations:- theinitialdesignandconstructionmustanticipatetherequirementsforallstagesandincludethosefeatureswhichareimpracticalorextremelycostlytoaddatalater time;- deferralofacomponent,systemorstructureshallnotincreasethecostofothercomponents,systemsorstructuresgreaterthantheamountofthecostsavedbydeferral. ITER will follow a staged approach to maximize the opportunities for deferring costandreducingthepeakdemandforfundinginanysingleyear.Thiswillalsoallowearlyexperimentalresultstobetterquantifythetechnicalrequirementsofsuccessivelyinstalledequipment.Inparticular,theabilitytostudysteadystateoperation will, if necessary, be provided through additional investment. ITERoperationisdividedintofourphases.Beforeachievingfulldeuterium-tritium(DT) operation, which itself is split into two phases, ITER is expected to go throughtwooperationphases,ahydrogen(H)phaseandadeuterium(D)phase,forcommissioning of the entire plant. The hydrogen phase is a non-nuclear phase, mainly planned for full commissioning ofthetokamaksysteminanon-nuclearenvironmentwherefullremotehandlingisnotrequired.ITER Technical BasisG A0 SP 2 01-06-01 R2.0Plant Design Specification Page 8Thedischargescenario ofthefullDTphasereferenceoperationsuchasplasmacurrentinitiation,currentramp-up,formationofadivertorconfigurationandcurrentramp-down can be developed or simulated in this phase.The semi-detached divertoroperation in DT plasma can be also checked since the peak heat flux onto the divertortarget will be of the same order of magnitude as for the full DT phase.Characteristicsofelectromagneticloadsduetodisruptionsorverticaldisplacementevents, and heat loads due to runaway electrons, will be basically the same as those oftheDTphase.Studiesofthedesign-basisphysicswillsignificantlyreducetheuncertaintiesofthefullDToperation.Mitigationofseveredisruptionsandverticaldisplacementevents(VDEs)orbettercontroloftheseeventsinlaterphaseswillbecome possible, leading to a more efficient DT operational phase.However,someimportanttechnicalissueswillnotbefullytestedinthisphasebecause of smaller plasma thermal energy content and lack of neutrons and energeticalpha-particles.Forexample,evaporationofthedivertortargetsurfaceexpectedatthe thermal quench phase of disruption, effects of neutron irradiation of the in-vesselmaterials, and alpha-particle heating of the plasma, will not be tested.The following studies can be carried out to prepare for the full DT phase:(1) accessibilityoftheH-modeandotherimprovedconfinementmodes(confirmation of the adequacy of the heating power);(2) verificationofoperationalcompatibilitywithplasmadensityclosetotheGreenwaldlimit,betalimit,q95~3,semi-detacheddivertor,lowimpuritylevel,andsufficientlygoodconfinement,whichisrequiredinthereferencehigh energy multiplication (Q) operation in the full DT phase; studies of highN operation by stabilising neoclassical modes with electron cyclotron currentdrive(ECCD)etc.,highplasmadensityoperationbyoptimizedfuellingetc.,andfurtherimprovedconfinementmodes;assessmentofthenecessitytoimprove these capabilities;(3) steadystateoperationwithanegativeorweakcentralmagneticshearandaninternaltransportbarrier;improvementofthebetalimitbystabilisingkinkmodesandresistivewallmodes;assessmentofthenecessitytoimprovecurrent drive capabilities and stability control.Ifthehydrogenphaseissubstantial,theinitialconstructioncostofITERcouldbesignificantlyreducedbydelayingtheinstallationofsomeofthenuclear-relatedfacilities.The actual length of the hydrogen operation phase will depend on the meritof this phase with regard to its impact on the later full DT operation. Operation in thisphase is subject to several uncertainties: how high the magnetic field can be withouttheplasmadensityexceedingtheGreenwaldlimit,andhowhightheplasmadensityneedstobetoaccesstheH-mode,avoidinglockedmodesandbeamshine-through,and ensuring adequate divertor operation.EC heating at the 2nd harmonic is expectedto help in these respects.ITER Technical BasisG A0 SP 2 01-06-01 R2.0Plant Design Specification Page 9 In the deuterium phase, neutrons will be produced, and tritium will be produced fromDDreactions.PartofthistritiumwillthenbeburntinDTreactions.Althoughthefusionpowerislow,theactivationlevelinsidethevacuumvesselwillnotallowhumanaccessafterseveraldeuteriumdischargeswithpowerfulheating.However,thecapacityoftheheattransfersystem(exceptforthedivertorandheatingdevices)could be minimal, and demand for the tritium processing system would be very small.Characteristics of deuterium plasma behaviour are very similar to those of DT plasmaexceptfortheamountofalphaheating.Therefore,thereferenceDToperationalscenarios,i.e.,highQ,inductiveoperationandnon-inductivesteadystateoperation,can be simulated in this phase.Since tritium already exists in the plasma, addition ofasmallamountoftritiumfromanexternalsourcewillnotsignificantlychangetheactivation level of the machine.Fusion power production at a significant power levelforashortperiodoftimewithoutfullyimplementingcoolingandtritium-recyclesystems which would be required in the subsequent full DT phase could therefore alsobedemonstrated.Byusinglimitedamountsoftritiuminadeuteriumplasma,theintegratedcommissioningofthedeviceispossible.Inparticular,theshieldingperformancecanbechecked.ThemajorachievementsintheDphaseshouldbeasfollows:- replacement of H by D, clean D plasma;- confirmation of L-H (mode) threshold power and confinement scalings;- establishmentofareferenceplasma(current,heatingpower,density,detached/semi-detached divertor, ELMy (edge localised mode) H-mode, etc.);- particle control (fuel/ash/impurity/fuelling/pumping);- steady-state operation with full heating power;- finalisation ofnuclear commissioning with a limited amount of tritium;- demonstrationofhighfusionpowercomparabletothenominalvalueforthefull DT burn, for a short time. FollowingthesetwophasestheITERplantwillhavebeenalmostfullycommissioned.MostoftheplasmaoperationalandcontroltechniquesnecessarytoachievethetechnicalgoalsoftheDTphasewillhavebeenmasteredbythen.DToperation can be divided into two phases predominantly oriented towards physics andengineering goals respectivelyDuringthefirstphasethefusionpowerandburnpulselengthwillbegraduallyincreased until the inductive operational goal is reached.Non-inductive, steady-stateoperation will also be developed. The DEMO-relevant test blanket modules will alsobetestedwheneversignificantneutronfluxesareavailable,andareferencemodeofoperation for that testing will be established.ThesecondphaseoffullDToperationwillemphasiseimprovementoftheoverallperformanceandthetestingofcomponentsandmaterialswithhigherneutronfluences. This phase should address the issues of higher availability of operation andfurther improved modes of plasma operation.Implementation of this phase should bedecided following a review of the results from the preceding three operational phasesand assessment of the merits and priorities of programmatic proposals.ITER Technical BasisG A0 SP 2 01-06-01 R2.0Plant Design Specification Page 10AdecisiononincorporatingtritiumbreedingduringthecourseofthesecondDTphase will be decided on the basis of the availability of tritium from external sources,theresultsofbreederblankettesting,andexperiencewithplasmaandmachineperformance.SuchadecisionwilldependontheR&Dcompletedduringthefirstphase indicating the viability of a tritium-breeding blanket, almost certainly within thesame space envelope as the shielding blanket on the outboard side, able to maintain alow tritium inventory with bakeout at 240C. Inalloperatingphases,ITERshallprovidefacilitiesforthereceipt,storage,processing/recyclingandutilisationofhydrogenisotopesforthetokamak.Apartfrom the H phase, this will include tritium, and the recycling capability shall includethe possibility to recover tritium from plasma-facing materials. ITER shall have a duty factor1capability of about 25%. Comprehensive plasma diagnostic information shall allow attainment and monitoringofreliablemodesofoperation.Inthefinalpartofthetwentyyearoperation,pulsereliability2shallbegreaterthan90%.Inthefinalpartofthetwentyyearoperation,ITER will also be required to operate at very high availability3 for periods lasting 1-2weeks.

1the ratio of plasma burn to total pulse length (including both electrical-on and dwell times)2 defined as the fraction of pulses for which: the necessary subset of data for achieving the goal of a given pulse is successfully acquired and archived,and no failure during the pulse which would preclude the initiation of the next pulse.3 the ratio of the product of the actual number of pulses and their average duration in an operation plan period inwhich the device is operational at its acceptable or planned performance level, to the product of the number ofpulses and their average duration which could be achieved during that run period in the absence of componentfailures and software errors.ITER Technical BasisG A0 SP 2 01-06-01 R2.0Plant Design Specification Page 112.2 Scope of the EDAThe scope of the EDA is described in the adjacent panel from the ITER EDA Agreement.The Parties shall conduct the following EDA:(a)to establish the engineering design of ITER including(i) a complete description of the tokamak and its auxiliary systems and facilities,(ii) detaileddesignswithspecifications,calculationsanddrawingsofthecomponents of ITER with specific regard to their interfaces,(iii) aplanningscheduleforthevariousstagesofsupply,construction,assembly,tests and commissioning of ITER together with corresponding plan for humanand financial resource requirements,(iv) specifications allowing [timely] calls for tender for the supply of items neededfor the start-up of the construction of ITER if and when so decided; (b) toestablishthesiterequirementsforITER,andperformthenecessarysafety,environmental and economic analyses; (c) toestablishboththeproposedprogramandthecost,manpowerandscheduleestimates for the operation, exploitation and decommissioning of ITER;(d) tocarryoutvalidatingresearchanddevelopmentworkrequiredforperformingtheactivitiesdescribedabove,includingdevelopment,manufacturingandtestingofscalable models to ensure engineering feasibility;(e) todevelopproposalsonapproachestojointimplementationfordecisionsbytheParties on future construction, operation, exploitation and decommissioning of ITER.For the EDA extension this is interpreted as in the following. (a) (ii) shall apply only for components critical to the construction decision during theEDA.Fortheremainder,thedesignshouldbescopedtoensurethatitcanbedeveloped in time within the constraints produced by the detailed design of the criticalcomponents. Sitespecificactivitiesshallincludedesignadaptationsandtheircostestimates,andsafety analysis and technical support for the preparation of license applications. ITER shall maintain a current estimate of the construction costs, as design progresses.TheJCTshallberesponsiblefordevelopingadaptationsofthedesignandcostestimatestocandidatesiteswhichthePartieshaveproposed.Afinalcostestimatemay be developed for the site selected with the assistance of the site host. ProjectschedulesshallbedevelopedbytheJCTrelevanttotheITERProjectandsiting decisions reached by the Parties. A cost estimate and schedule for deferred components, systems or structures shall bedevelopedsothattheymaybeprocured,constructedandcommissionedpriortothestage in which they are required. TheJCTshallmaintaincurrentestimatesoftheR&Dcostsasthedesignprogressesand shall justify deviations from the construction costs given above.ITER Technical BasisG A0 SP 2 01-06-01 R2.0Plant Design Specification Page 122.3 Design PrinciplesBasedonalltheforegoing,theITERdesignduringtheEDAhasadoptedthefollowingdesign principles: optimise the design for the objectives of the first phase of active operation and ensureflexibilityandcapabilitytoaccommodatethegoalsandconstraintsoffollowingphases; within the given resources, maximise the development of the basic tokamak machineand defer that of external systems that can be changed or added later; useadvancedbutproventechnologies,butkeeptheflexibilitytointroducenewtechnologies when proven; avoid irrevocable choices today if they may be made later when better information isavailable; for systems to be developed and designed later, reserve the maximum space available; avoid on-site production and testing as much as possible; nevercompromisesafetyofthemachineoperationtoimproveperformanceordecrease cost; plasma-facing components should be excluded from safety functions; emphasise passive safety in the design; maximisesimplicity,fail-safeandfault-tolerantdesign,redundancyanddiversity(wherever appropriate), independence, and testability.3 Safety Principles and CriteriaThis section provides: the safety objectives, principles and criteria that are the high level requirements whichshould be maintained independently from any design; generic elements for the implementation of the safety approach so that each Party candecidehowtheimplementationwillsatisfytheirnationallawsandregulations;orpossiblysothattheITERPartiescanagreeonacommonsafetyapproachforaninternational realisation of a first of a kind machine like ITER.Thissectionfocusesonthesafetyandenvironmentalissuesfromthedesignpointofview.Additionalaspectswouldneedtobeaddressedtomorefullyelaboratethesafetyprinciplesand generic elements of a safety approach for the operation phase.ITER Technical BasisG A0 SP 2 01-06-01 R2.0Plant Design Specification Page 13Inthefollowing,theword'shall'isusedtodenoteafirmrequirement,theword'should'todenote a desirable option and the word 'may' to denote permission, i.e. neither a requirementnor a desirable option.3.1 Safety ObjectivesA main goal of ITER is to demonstrate the safety and environmental potential of fusion andthereby provide a good precedent for the safety of future fusion power reactors.However, itisnecessarytoaccountfortheexperimentalnatureoftheITERfacility,therelateddesignandmaterialchoices,andthefactthatnotallofthemaresuitedforfuturefusionpowerreactors.Toaccomplishthis,ITERsafetyneedstoaddressthefullrangeofhazardsandminimise exposure to these, and to permit siting by any Party.The following safety objectives are taken into account: Generalsafety:toprotectindividuals,societyandtheenvironment;toensureinnormaloperationthatexposuretohazardswithinthepremisesandduetoreleaseofhazardousmaterialfromthepremisesiscontrolled,keptbelowprescribedlimitsandminimised;topreventaccidentswithhighconfidence,toensurethattheconsequencesofmorefrequentevents,ifany,areminor;toensurethattheconsequences of accidents are bounded and the likelihood is small. No evacuation: to demonstrate that the favourable safety characteristics of fusion andappropriatesafetyapproacheslimitthehazardsfrominternalaccidentssuchthatthereis,forsomecountries,technicaljustificationfornotneedingevacuationofthe public. Waste reduction: to reduce radioactive waste hazards and volumes.ITER shall be developed in such a way that it can be sited by any participant in the ITEREDA Agreement with minor design modifications.3.2 Safety PrinciplesThe following principles shall be considered in the safety approach.These safety principlesnot only provide direction to guide the design, but also include on-going, independent reviewand assessment to ensure the design will meet safety objectives.3.2.1 'As Low as Reasonably Achievable'Asabasicprinciple,exposurestohazardsshallbekeptaslowasreasonablyachievable(ALARA), economic and social factors being taken into account.3.2.2 Defence-in-DepthAllactivitiesaresubjecttooverlappinglevelsofsafetyprovisionssothatafailureatonelevelwouldbecompensatedbyotherprovisions.Priorityshallbegiventopreventingaccidents.Protectionmeasuresshallbeimplementedasneeded.Inaddition,measurestoITER Technical BasisG A0 SP 2 01-06-01 R2.0Plant Design Specification Page 14mitigatetheconsequencesofpostulatedaccidentsshallbeprovided,includingsuccessivebarriers for confinement of hazardous materials.3.2.3 Passive SafetyPassivesafetyshallbegivenspecialattention.Itisbasedonnaturallaws,propertiesofmaterials,andinternallystoredenergy.Passivefeatures,inparticularminimisationofhazardousinventories,helpassureultimatesafetymarginsinadditiontofusion'sfavourablesafety characteristics.3.2.4 Consideration of ITERs Safety CharacteristicsThesafetyapproachshallbedrivenbyadeploymentoffusion'sfavourablesafetycharacteristics to the maximum extent feasible. Relevant characteristics are:the fuel inventory in the plasma is always below 1 g so that the fusion energy contentis small;plasmaburnisterminatedinherentlywhenfuellingisstoppedduetothelimitedconfinement by the plasma of energy and particles;plasmaburnisself-limitingwithregardtopowerexcursions,excessivefuelling,andexcessive additional heating;plasmaburnispassivelyterminatedbytheingressofimpuritiesunderabnormalconditions (e.g. by evaporation or gas release or by coolant leakage);the energy and power densities are low;the energy inventories are relatively low;large heat transfer surfaces and big masses exist and are available as heat sinks;confinement barriers exist and must be leak-tight for operational reasons.However, the experimental nature of ITER shall also be addressed in the safety approach bythe following measures.Arobustsafetyenvelopewillbeprovidedtoenableflexibleexperimentalusage.SinceITERisthefirstexperimentalfusiondeviceonareactorscale,itwillbeequippedwithanumberofexperimentalcomponents,inparticularinsidethevacuumvessel.Nosafetyfunctionwillbeassignedtoexperimentalcomponents.However,experimentalcomponentswillbedesignedconsideringtheexpectedloadsfromplasmatransients,inordertoreducethedemandsonothersystemswhichdohave a safety function.Nevertheless, faults in experimental components that can affect safety will be subjecttosafetyassessments.Onthisbasis,relatedmeasureswillbeincorporatedinthedesign as appropriate.ITER Technical BasisG A0 SP 2 01-06-01 R2.0Plant Design Specification Page 15The experimental programs will be developed in such a way that design modificationswilltakeaccountofexperiencefromprecedingoperationsandwillstaywithinthesafety envelope of the design.3.2.5 Review and AssessmentSafety assessments shall be an integral part of the design process and results will be availableto improve the design and to assist in the preparation of safety documentation for regulatoryapproval.Theseanalysesshallcomprisenormaloperation,allcategoriesofaccidents,andwaste characterisation.Anassessmentshallbemadeofpotentialeffluentsfromthesitethroughoutitslifetime.Alleffluents(airborneandwaterborne)shallbeidentifiedandtheirquantityandcharacteristicsestimated. Effluent assessment shall address normal operation and maintenance. Releases ofradioactivematerialsshallbeassessedaspartofademonstrationthatsucheffluentsareALARA.A plant safety assessment shall be made, including a systematic review of the ways in whichcomponents might fail and identifying the consequences of such failures. It will also supportthe Safety Importance classification of components (see 3.4.2). To approach completeness asfaraspossible,acomprehensiveidentificationprocedureshallbeapplied:Postulatedinitiatingevents(PIEs)shouldbeidentifiedbyasystematicbottom-upmethodliketheFailure Modes and Effects Analysis (FMEA) as well as by a top-down approach like GlobalEventTreesorMasterLogicDiagrams.Asetofreferenceeventsshallbeselectedthatencompass the entire spectrum of events.Analysis of reference events shall also address lossof power and aggravating failures in safety systems.Hypothetical sequences should be used to investigate the ultimate safety margins. The intentis to demonstrate the robustness of the safety case with regard to the projects objectives andradiological requirements.3.3 Safety and Environmental CriteriaRegulatoryapprovalisrequiredbeforetheconstructionofITERandpreparationsforthefuture application for approval shall be included in the design process.Before site selection,thedesignwillfollowinternationalrecommendations,inparticulartechnology-independentones. Limits on doses to the public and staff from radioactivity and related releases shall bemetbydesign,construction,operationanddecommissioning.TheseprojectlimitsshallfollowtherecommendationsbytheICRP(InternationalCommissiononRadiationProtection)andtheIAEA(InternationalAtomicEnergyAgency).Followingsiteselection,Host Country regulations will apply.An important element of the safety analyses is the assessment of consequences.Doses fromreleasestotheenvironmentwilldependonthecharacteristicsofthesite,andthereforetheprojecthasfocussedonlimitingthephysicalreleasesthemselves,ratherthanthedose.Releases to the environment shall be limited and not exceed the guidelines established by theprojectinTable3-1.Theyshouldbeminimisedbydesignimprovementinlinewiththeprinciple of ALARA.ITER Technical BasisG A0 SP 2 01-06-01 R2.0Plant Design Specification Page 16Table 3-1Project Release GuidelinesEvents or Conditions Goal Project Release GuidelineNormal Operation, comprisingevents and plant conditions plannedand required for ITER normaloperation, including some faults,events or conditions which can occuras a result of the ITER experimentalnature.Reduce releases to levels as low asreasonably achievable but ensurethey do not exceed project releaseguideline for Normal Operation.< 1 g T as HT and 0.1 T as HTO and1 g metal as AP and 5 g metal asACP per year.Incidents, or deviations fromnormal operation, comprising eventsequences or plant conditions notplanned but likely to occur due tofailures one or more times during thelife of the plant but not includingNormal Operation.Reduce likelihood and magnitude ofreleases with the aim to preventreleases, but ensure they do notexceed project release guideline forIncidents.< 1 g T as HT or 0.1 g T as HTO or1 g metal as AP or 1 g metal as ACPor combination of these per event.Accidents, comprising postulatedevent sequences or conditions notlikely to occur during the life of theplant.Reduce likelihood and magnitude ofreleases but ensure they do notexceed project release guideline forAccidents.< 50 g T asHT or 5 g T as HTO or50 g metal as AP or 50 g metal asACP or combination of these perevent.HT:elemental tritium (including DT); HTO:tritium oxide (including DTO); AP:divertor or first-wallactivation products; ACP:activated corrosion products.IAEArecommendationsareusedtointerprettheno-evacuationobjective:thegenericoptimisedinterventionvaluefortemporaryevacuationis50mSvofavertabledoseinaperiod of no more than 1 week.ITERshallcomplywiththeICRPrecommendationsregardingpublicandoccupationalexposures(seeTable3-2forguidelinesestablishedbytheproject).TheradiationprotectionpracticesshallbeconsistentwiththeIAEAandICRPrecommendationsandshouldmakeuseofbestpractices.Inparticular,effortsshallbemadetodesignsuchthatexposuresduringoperation,maintenance,modificationanddecommissioningareALARA,economic and social factors being taken into account.Activatedmaterialsareconsideredlong-termwasteifcriteriaforunconditionalclearancefollowing IAEA recommendations are not met after a decay period of 100 years.Table 3-2 Limits and Project Guidelines for Doses from Occupational ExposureDose LimitsICRP recommended limit for annual individual workerdoses20 mSv/year averaged over 5 yearsnot to exceed 50 mSv/yearProject GuidelinesAnnual individual worker dose < 5 mSvIndividual dose for any given shift < 0.5 mSv/shift3.4 Elements of the Generic Safety ApproachTherecanbeanumberofacceptablesafetyapproachestomeetsafetyobjectives.Thefollowing sections provide the elements of a generic safety approach implementing the ITERsafety principles.ITER Technical BasisG A0 SP 2 01-06-01 R2.0Plant Design Specification Page 17Thesafetyapproachshallcoverbothpublicandoccupationalsafetyfornormaloperation,incidents,andaccidents.Theapproachshalluseacombinationofdesignfeaturesandadministrativecontrolstoprotectthesitestaffandthepublicfromhazardsandtocontrolreleasesofradionuclidesandhazardousmaterialsfromthefacility.Thelevelofprotectionrequired depends on the level of the hazard present in the facility.3.4.1 ConfinementConfinementofradioactiveandtoxicmaterialsisafundamentalsafetyrequirement.Confinement is provided by all types of physical and functional barriers which protect againstthe spread and release of radioactive material.Containment is a special type of confinementwhenitcanaccommodatesignificantpressurisation.Releaseswouldmostsignificantlyoccuruponbreachofbarriers,henceconfinementbarriersshallbeprotectedbyappropriatemeasures such as heat removal, control of energies and monitoring.Thebarriersshallbeofsufficientnumber,strengthandperformance(intermsofleaktightness,retentionfactors,reliability,etc.)sothatreleasesofradioactiveand/ortoxicmaterialsduringnormaloperationandforincidentsandaccidentsdonotexceedtheprojectrelease guidelines listed in Table 3-1.Thedesignofconfinementbarriersmaybegraded.Significant,vulnerable,radioactiveand/ortoxicinventorieswillrequirehighlyreliablebarriers,whereasmoderateandsmallinventories may require less reliable barriers.The design basis for the confinement barriers shall take into account all events, ranging fromtheinitiatingeventstoconsequentialfailures,loadsandenvironmentalconditionsasidentified by the safety assessments taking into account the experimental nature of ITER.Thedesignofconfinementbarriersshallimplementtheprinciplesofredundancy,diversityandindependence.Specifically,inthecaseofmultiplebarriers,failureofonebarriershallnot result in the failure of another barrier.Afterpressurisationduetoanaccident,confinementvolumesshallbereturnedtobelowatmosphericpressurewithinaspecifiedperiodfollowingtheaccidentandafiltered,monitoredpathwayshallbeprovidedtomaintainthepressureinsidethevolumetobelowatmospheric pressure.Measurestoprotectconfinementbarriersshallbeincorporatedasrequiredconsideringthepotential for damage.Considerationshouldalsobegiventothemitigationofconsequencesfromconfinementdegradationby,failuresbeyondaccidentsconsideredinthedesignassessment,i.e.byhypothetical sequences.3.4.2 Component ClassificationSystems,structuresandcomponents(termed'components'inthefollowing)importantforpersonnelandpublicsafety(classifiedasSafetyImportant,i.e.SIC)shallbeidentifiedandITER Technical BasisG A0 SP 2 01-06-01 R2.0Plant Design Specification Page 18appropriate requirements set.The identification and setting of requirements shall be based onthe consequences of failure as determined by safety assessments.The importance to safety ofcomponentsisnotuniform,thereforerequirementsshouldbeusedtodevelopcomponent-specific safety specifications, taking into account that operational requirements may be morerestrictive.Thequalitylevelrequiredforcomponentsshouldbecommensuratewiththerequired reliability.3.4.3 EarthquakeBefore the ITER site is decided, an assumption for design and safety analysis purposes is toconsiderthreeseismiclevels(SL-2,SL-1,SL-0)ofgroundmotion.ThesearespecifiedinSection 4.III.A.5.Components identified as important to safety (SIC, Section 3.4.2) shall not be damaged as aresult of an SL-0/SL-1 earthquake.Those SIC components that are required to perform a safety function during or after an SL-2earthquakeshallbeidentifiedanddesignedsuchthatthecapabilitiesaremaintained.Thecollapse, falling, dislodgement or any other spatial response of a component as a result of anearthquakeshallnotjeopardisethefunctioningofothercomponentsprovidingasafetyfunction.Thecombinationofloadsfromearthquakeswithotherloadingeventsshallbeconsidered.3.4.4 Environmental QualificationSICcomponentsshallbedesignedtowithstandtheenvironmentalconditionscreatedbyanaccident (such as pressure, temperature, radiation, flooding) under which they are expected toperform their safety function.3.4.5 FireITER shall be designed to assure that the: required safety functions are maintained in case of fire, through a combination of fireprevention,firedetectionandsuppression,andmitigationofadverseeffectsoncomponents important to safety (SIC); propagationoffireconsequencesthatmayimpairsafetyfunctionsarelimitedbyspatial separation, redundancy, diversity, etc.3.4.6 Decommissioning and WasteThe design shall support decommissioning as appropriate for an experimental device by: shielding to reduce induced activation of ex-vessel components during operation; use of modular components to simplify dismantling and reduce waste; use of remote handling equipment and procedures developed for normal operation.ITER Technical BasisG A0 SP 2 01-06-01 R2.0Plant Design Specification Page 19The design shall reduce the quantities of radioactive liquid waste.Thedesignshallfurtherincorporatemeanstoreducethevolumesandradiotoxicityofmaterials which may remain as long-term waste after decommissioning by: re-use of components to the extent practical; limiting impurities in the materials to allow their clearance as early as practical.3.4.7 EffluentsThe design shall: prove that the effluents comply with the project guidelines in Table 3-1; reduce radioactivity such that effluents are ALARA; monitor the effluents.3.4.8 Radiation ProtectionITERshallimplementdesignandadministrativemeasurestoprotecton-sitestaffagainstexposure to radiological hazards.Theworktobeperformedduringoperation,maintenance,andrepairshallbeassessedtodetermine the accessibility and the estimated exposures for activities, against the radiologicalrequirementsinTable3-2andagainstrecognisedlimitsofexposuretoconventional(non-nuclear) hazards.ThedesignshallprovidethemeanstoensurethatthespreadofcontaminationandoccupationalexposurestoradiologicalhazardsarekeptALARAduringoperation,maintenance and repair. This should include, but not be limited to, access control and zoning,theprovisionofremotehandling,shielding,contaminationcontrol,anddecontaminationequipment as appropriate.To assure that the radiological requirements are met, through the entire life cycle of ITER, aradiationprotectionprogram(RPP)shallbedevelopedandimplemented.ThescopeoftheRPP includes programs and processes required for the safety of staff during normal operationand maintenance work. The objectives of the RPP are to: prevent acute over-exposures; prevent occupational doses over legal limits; maintain staff doses ALARA; minimise spread of contamination.ITER Technical BasisG A0 SP 2 01-06-01 R2.0Plant Design Specification Page 20Access Control and ZoningAll areas of the ITER plant shall be zoned depending on the anticipated radiological hazardand conditions during short-term maintenance.During activities/events that cause prohibitiveradiationlevels(e.g.plasmaburnphase,in-vesselcomponentsmovedoutofthevacuumvessel,etc.),areasthatareotherwiseaccessiblemaybedesignatedasRestrictedforthedurationoftheactivity,andphysicalaccessshouldbeprevented.Suchlocationsshallbereturned to accessible only after a formal change control.Table3-3liststheRadiationAccessZones,personnelaccesslimitations,anddefinestheconditions acceptable in these zones. For contamination control, monitoring is required whencrossing from a higher to a lower contamination hazard area, and ventilated air flow shall notmove from a higher to a lower contamination hazard area.Table 3-3 Area Classifications and Radiation Access ZonesAccess Zone(Area Classification)Access Limitations Airborne / Total Dose Rate /Area Contamination CharacteristicsZone A(Non-SupervisedArea)Unlimited Access. No airborne contamination.Dose rate < 0.5 Sv/h;WHITE contamination control zones only:Nosurface or airborne contamination and no reasonablepossibility of cross-contamination.Zone B(Supervised Area)Limited Access for NRW. (a)Unlimited Access for RW. (a)Total dose rate (internal + external) < 10 Sv/h;GREEN contamination control zones acceptable:Noloose contamination tolerated.May be subject totemporary surface or airborne cross-contamination,airborne should not exceed 1 DAC.Zone C(Controlled Area)Limited Access for allworkers.Access requires planningand an appropriate level ofapproval for the hazards andthe class of personnelrequiring access.< 100 DAC and < 1 mSv/h;AMBER contamination control zones acceptable:Airborne and loose surface contamination toleratedbut must be identified and controlled.Contaminationlevels shall be maintained ALARA taking intoaccount the risk of exposure, capability of availableprotective equipment, possibility of contaminationspread, and cost. Airborne contamination in AMBERzones should not exceed 100 DAC.Zone D(Controlled /Restricted Area)These are restricted accessareas, entry occurs onlywith a high level ofapproval from both anoperational and aradiological safety view.These areas shall havephysical barriers to preventinadvertent personnel entry.Airborne >100 DAC or external dose rate > 1 mSv/h;RED contamination control zones are only toleratedin Zone D.These areas have permanent or higherthan AMBER levels of contamination.(a) Personnel performing work requiring exposure to radiological hazards will be designated as RadiationWorkers (RW).All other personnel, including non-designated visitors, will be treated as Non-RadiationWorkers (NRW).Notes:DAC = Derived Air Concentration: unprotected exposure to 1 DAC = 10 Sv/h1 DAC HTO = 3.1x105 Bq/m3 = 8.4x10-6 Ci/m3For internal dose rate, hazard defined in DAC of airborne contaminationFor external dose rate, hazard defined as Sv/hITER Technical BasisG A0 SP 2 01-06-01 R2.0Plant Design Specification Page 213.4.9 Hazardous MaterialsHandling,storageandtreatmentofhazardousmaterials(suchasintermediatelystoredradioactive waste, and chemically toxic or reactive materials) shall be designed to: limit exposure of site staff during all operations; limit the spread of contamination during all operations; ensure compatibility with other materials and the surrounding environment; prevent chemical reactions during normal operation and accidents.BerylliumTheprojectguidelinesforberylliumconcentrationsgiveninTable3-4areonetenthoftheoccupational exposure limits recognised internationally.Table 3-4Project Guidelines for Exposure to BerylliumSource Beryllium ConcentrationAirborne (Occupational Exposure Limit)0.2 g/m3Surface contamination10 g/m23.4.10 Conventional HazardsConventionalhazardsshallbecontrolledaccordingtoappropriatestandards.Suchhazardsincludeelectromagneticfields,asphyxiation,electrocution,cryogenicmaterials,vacuum,crane loads, and rotating machinery.Magnetic Field HazardsThe project guidelines for exposure to magnetic fields are listed in Table 3-5.Table 3-5Project Guidelines for Exposure to Magnetic Fields B (T)Uncontrolled access B < 10 mTDaily exposure B x time 60 mT-hRestricted access B > 100 mT3.4.11 Security and ProliferationThe design shall provide measures to prevent unauthorised entry to the site and its premisesto preclude theft or unauthorised removal of nuclear materials and sabotage.Design provisions, operational surveillance and administrative measures shall be provided tocomplywithanyinternationalagreementsontritium,lithium-6andrelatedsensitivetechnologies with regard to proliferation control.ITER Technical BasisG A0 SP 2 01-06-01 R2.0Plant Design Specification Page 224 Site Requirements & AssumptionsThis following text is reproduced verbatim from the ITER Site Requirements and ITER SiteDesign Assumptions (N CL RI 3 99-10-19 W 0.2) updated October 1999.IntroductionThe objective of this document is to define a set of requirements that are compulsory for theITER site, supplemented by assumptions about the ITER site which are used for design andcostestimatesuntiltheactualITERsiteisknown.PartIofthisdocumentcontainstheprinciplesforthedevelopmentofthesiterequirementsandsitedesignassumptions.PartIIofthisdocumentcontainsthecompulsoryrequirementswhicharederivedfromtheITERdesign and the demands it makes on any site.Part III of this document contains site designassumptions which are characteristics of the site assumed to exist so that designers can designbuildings, structures and equipment that are site sensitive.Both the Site Requirements and the Site Design Assumptions are organized in the followingcategories: Land Heat Sink Energy and Electrical Power Transport and Shipping External Hazards and Accident Initiators Infrastructure Regulations and DecommissioningEachofthecategoriesissubdividedintorelatedelements.Someofthecategoriesarebroadlydefined.Forinstance,Infrastructureincludespersonnel,scientificandengineeringresources,manufacturingcapacityandmaterialsforconstructionandoperation.Requirements and assumptions for the various elements are justified in the Basesstatements.These statements explain the rationale for their inclusion and provide a perspective in whichthey may be used.I Principles for Site Requirements and Site Design Assumptions1. The compulsory site requirements are based on the ITER site layout and plant design.These requirements are firm in the sense that reasonable reconfiguration of the plantdesignwillnotresultinalessdemandingsetofrequirements.Someoftherequirementsarebasedinpartonhowtheplantandsomeofitsmajorcomponents,such as the vacuum vessel and the magnet coils, will be fabricated and installed.2. ThisdocumentalsoaddressestheassumptionsthathavebeenmadetocarryouttheITER design until a decision on siting is reached. These site design assumptions formsomeofthebasesfortheITERconstructioncostestimateandschedule.Theassumptions are not compulsory site requirements, but are guidelines for designers tofollow until the actual site is known.ITER Technical BasisG A0 SP 2 01-06-01 R2.0Plant Design Specification Page 233. Therequirementsforpublicsafetyandenvironmentalconsiderationsare,bytheirnature,sitesensitive.Also,theregulatoryrequirementsforsiting,constructing,operatinganddecommissioningITERarelikelytobesomewhatdifferentforeachpotentialhostcountry.Therefore,theSafetyContactPersons,designatedbyeachpotentialHostCountry,willhelptheProjectTeamtoconsideranyparticularrequirements that siting in their own country would impose.Until that time, the ITERPlant will be designed to a set of safety and environmental assumptions contained intheITERPlantSpecifications[see3],whichareexpectedtoapproximatetheactualrequirements.Sitesensitiveconsiderationsduringoperationsuchastheshipmentofradioactive materials including tritium to the site, the temporary storage of wastes onthesite,theshipmentofwastesfromthesiteandoftheeffluentsfromITERduringnormalandoff-normaloperation,areaddressedwiththedesignanalysis.Accordingly,aGenericSiteSafetyReport("Non-Site-SpecificSafetyReport")willbe available as a firm basis on which the Site Safety Report will later be established tosatisfy the licensing authorities of the Host Country.4. ThedecommissioningphaseoftheITERPlantdeservesspecialattention.Intheabsence of firm guidance and without prejudice to future negotiations of the Parties, itisassumedthattheorganizationinchargeofoperatingITERwillhaveafinalresponsibilityto"deactivate"theplant.Inthiscontext,"deactivation"isthefirstphaseofdecommissioningandincludesallactionstoshutdowntheITERplantandplace it in a safe, stable condition.The dismantling phase of decommissioning, whichmighttakeplacedecadesafterthe"deactivation"phase,isassumedtobecometheresponsibility of a new organization within the host country.A technical report on thestrategyofdeactivationanddismantlingwillbedescribedinsidethedesignreportdocumentation.5. Inconclusion,thesitedesignassumptionsareveryimportant,becausewithoutthemprogress is very limited for the site sensitive designs of buildings, power supplies, sitelayout and safety/environmental studies.These assumptions were selected so that thedesignwouldnotbesignificantlyinvalidatedbyactualsitedeviationsfromtheassumptions. Deviations from the site design assumptions by the actual ITER site mayrequire design and/or construction modifications, but these modifications are expectedtobefeasible.Themodificationsmayrevisethecostestimateandtheconstructionschedule.II Site RequirementsA. Land1. Land AreaRequirement The ITER Site shall be up to 40 hectares in area enclosed within a perimeter.All structures and improvements within the perimeter are the responsibility ofthe ITER project. Land within the perimeter must be committed to ITER usefor a period of at least 30 years.Bases TheminimumareafortheITERSiteispredicatedonsufficientareaforthebuildings,structuresandequipmentwithallowancesforexpansionofcertainbuildings if required for extension of the ITER programme.ITER Technical BasisG A0 SP 2 01-06-01 R2.0Plant Design Specification Page 24Thetimeperiodisspecifiedtocovertheconstruction(~10years)andoperations(~20years)phases.Beyondthat,therequirementsforanydecommissioning will be the responsibility of the Host Country.2. Geotechnical CharacteristicsRequirement TheITERSiteshallhavefoundationsoil-bearingcapacityadequateforbuilding loads of at least25 t/m2 at locations where buildings are to be built.Nevertheless,itisexpectedthatitwillbepossibletoprovideatthespecificlocationoftheTokamakBuildingmeanstosupporttheaverageloadof65 t/m2atadepthof25m.Thesoil(toadepthof25m)shallnothaveunstablesurroundinggroundfeatures.Thebuildingsitesshallnotbesusceptible to significant subsidence and differential settlement.Bases TheITERtokamakiscomposedoflarge,massivecomponentsthatmustultimatelybesupportedbythebasematofthestructuresthathousethem.Thereforesoil-bearingcapacityandstabilityunderloadsarecriticalrequirementsforanacceptablesite.TheTokamakBuildingiscomposedofthreeindependenthallsonseparatebasemats,butservedbythesamesetoflarge,overheadbridgecranes.Craneoperationwouldbeadverselyaffectedby significant subsidence and differential settlement.3. Water SupplyRequirement TheITERSitehostshallprovideacontinuousfreshwatersupplyof0.2 m3/minute average and 3 m3/minute peak consumption rates.The averagedailyconsumptionisestimatedtobeabout200m3.Thiswatersupplyshallrequirenotreatmentorprocessingforusessuchaspotablewaterandwatermakeup to the plant de-mineralised water system and other systems with lowlosses.Bases The ITER plant and its support facilities will require a reliable source of highqualitywater.Thepeakrateof3m3/minuteisspecifiedtodealwithconditionssuchasleakageorfires.Thiswatersupplyisnotusedforthecoolingtowersorotheruseswhichmaybesatisfiedbylowerquality,"raw"water.4. Sanitary and Industrial SewageRequirement The ITER Site host shall provide sanitary waste capacity for a peak ITER sitepopulation of 1000.The host shall also provide industrial sewage capacity foran average of 200 m3/day.Bases The ITER project will provide sewer lines to the site perimeter for connectionto the sewer service provided by the host.The peak industrial sewage rate isexpected to be adequate to deal with conditions such as leaks and drainage ofindustrialsewagestoredintanksuntilitcanbeanalyzedforrelease.Rainwater runoff is not included in industrial sewage.ITER Technical BasisG A0 SP 2 01-06-01 R2.0Plant Design Specification Page 25B. Heat SinkRequirement TheITERSiteshallhavethecapabilitytodissipate,onaverage,450MW(thermal) energy to the environment.Bases ITERanditsassociatedequipmentmaydevelopheatloadsashighas1200 MW (thermal) for pulse periods of the order of 500 s. The capability todissipate1200MWshouldbepossibleforsteady-stateoperationwhichisassumedtobecontinuousfullpowerforonehour.DutyCyclerequirementsfortheheatsinkatpeakloadswillnotexceed30%.Theaverageheatloadwould be no more than 450 MW for periods of 3 to 6 days.C. Energy and Electrical PowerITER Plant Steady State Electrical LoadsRequirement TheITERSiteshallhavethecapabilitytodrawfromthegrid120MWofcontinuouselectricalpower.Powershouldnotbeinterruptedbecauseofconnectionmaintenance.Atleasttwoconnectionsshouldbeprovidedfromthe supply grid to the site.Bases TheITERPlanthasanumberofsystemswhichrequireasteady-statesupplyofelectricalpowertooperatetheplant.Itisnotacceptabletointerruptthispowersupplyforthemaintenanceoftransmissionlines,thereforetheoffsitetransmission lines must be arranged such that scheduled line maintenance willnot cause interruption of service.This requirement is based on the operationalneeds of the ITER Plant.Maintenanceloadsareconsiderablylowerthanthepeakvaluebecauseheavyloads such as the tokamak heat transfer and heat rejection systems will operateonly during preparations for and actual pulsed operation of the tokamak.D. Transport and Shipping1. Maximum Size of Components to be ShippedRequirement The ITER Site shall be capable of receiving shipments for components havingmaximum dimensions (not simultaneously) of about:Width -9mHeight -8mLength- 15mBases Inordertofabricatethemaximumnumberofcomponents,suchasmagnetcoilsandlargetransformers,offsite,theITERsitemusthavethecapabilityofreceivinglargeshipments.Forthereferencecase,itisassumedthatonlythe Poloidal Field Coils will be manufactured on site, unless the possibility oftransportingandshippingtheselargecoilsisprovenfeasible.Forthesamereason, it is also assumed that the [Central Solenoid] will be assembled on siteITER Technical BasisG A0 SP 2 01-06-01 R2.0Plant Design Specification Page 26from six modules, unless it proves feasible that the Assembly may be suppliedasonelargeandcompleteunit.Thecryostatwillbeassembledonsitefromsmallerdeliveredparts.Thewidthisthemostcriticalmaximumdimensionand it is set by the Toroidal Field Coils, which are about 9 m wide.The heightisthenextmostcriticaldimensionwhichissetbythe40VacuumVesselSector.Alengthof15misrequiredfortheTFcoils.Thefollowingtableshows the largest (~ 100 t or more) ITER components to be shipped:Largest ITER Components to be ShippedComponentPkgs Width (m) Length (m) Height (m)Weight (t)Each Pkg.TF Coils 18 9 14.3 3.8 280Vac. Vessel 40Sector9 8 12 8575CS Modules 6 4.2 4.2 1.9 100Large HVTransformer3 4 12 5 250Crane TrolleyStructure*2(14)(18) (6) (600)*Crane dimensions and weight are preliminary estimates.PF Coils and CS Assembly**ComponentPkgs Width (m) Length (m) Height (m)Weight (t)Each Pkg.PF1 1 9.5 9.5 2.4 200PF2 1 18.5 18.5 1.9 200PF3 1 25.5 25.5 1.2 300PF4 1 26.0 26.0 1.2 450PF5 1 18.2 18.2 2.4 350PF6 1 10.8 10.8 2.4 300CS Assembly 1 4.2 18.8 4.2 850**Note that transportation and shipping of the PF Coils and of the CS Assembly are not requirements, butcould be considered an advantage. Note, too, that the PF Coils dimensions are for the coil and connection box envelope, and that for eachcoil there are vertical protrusions of ~ 1.5 1.8 m for the terminals.ITER Technical BasisG A0 SP 2 01-06-01 R2.0Plant Design Specification Page 272. Maximum Weight of ShipmentsRequirement TheITERSiteshallbecapableofreceivingaboutadozencomponents(packages)havingamaximumweightof600tandapproximately100packages with weight between 100 and 600 t each.Bases Inordertofabricatethemaximumnumberofcomponents,includingmagnetcoils, off site, the ITER site must have the capability of receiving very heavyshipments.Thesingleheaviestcomponent(VacuumVesselSector)isnotexpected to exceed 600 t.All other components are expected to weigh less.E. External Hazards and Accident InitiatorsNo Compulsory Requirements.F. InfrastructureNo Compulsory RequirementsG. Regulations and DecommissioningDetailsoftheregulatoryframeworkforITERwilldependontheHostCountry.Ataminimum,theHostsregulatorysystemmustprovideapracticablelicensingframeworktopermitITERtobebuiltandtooperate,taking into account, in particular, the following off-site matters:1. thetransportofkilogramsoftritiumduringthecourseofITERoperations;2. theacceptanceandsafestorageofactivatedmaterialintheorderofthousands of tonnes, arising from operation and decommissioning.TheagreementwiththeHostshouldprovidefortheissueoftheliabilityformattersbeyondthecapacityoftheprojectthatmayarisefromITERconstruction, operation and decommissioning.III Site Design AssumptionsThefollowingassumptionshavebeenmadeconcerningtheITERsite.Thesesitedesignassumptions are uniformly applied to all design work until the actual ITER Site is selected.A. Land1. Land AreaAssumption Duringtheconstructionitwillbenecessarytohavetemporaryuseofanadditional30hectaresoflandadjacenttoorreasonablyclosetothecompulsorylandarea.Itisassumedthislandisavailableforconstructionlaydown,fieldengineering,pre-assembly,concretebatchplant,excavationspoils and other construction activities.Duringoperatingphases,thislandshouldbeavailableforinterimwastestorage,heavyequipmentstorageandactivitiesrelatedtothemaintenanceorimprovement of the ITER Plant.ITER Technical BasisG A0 SP 2 01-06-01 R2.0Plant Design Specification Page 28Bases Theassumptionsmadeforthecostandscheduleestimatesarebasedonconstructionexperiencewhichusesanadditionalareaof25hectares.Onlyaverylimitedamountofvehicleparkingspace(5hectares)isallocatedtothecompulsoryarea,whereasasimilaramountwillberequiredtosatisfytemporary needs during construction.2. TopographyAssumption The ITER site is assumed to be a topographically "balanced" site.This meansthatthevolumesofsoilcutsandfillsareapproximatelyequaloverthecompulsorylandareainRequirementA.1.Themaximumelevationchangefor the "balanced" site is less than 10 m about the mean elevation over the landarea in the compulsory requirement.3. Geotechnical CharacteristicsAssumptionThe soil surface layer at the ITER Site is thick enough not to require removalof underlying hard rock, if present, for building excavations, except in the areaunder the Tokamak Building itself, at an excavation of about 25 m.4. Hydrological CharacteristicsAssumption Groundwaterisassumedtobepresentat10mbelownominalgrade,wellabovethetokamakbuildingembedmentofupto25mbelownominalgrade.Thisassumptionwillrequireengineeredgroundwatercontrolduringtheconstruction of the tokamak building pit.5. Seismic CharacteristicsAssumption Using the IAEA seismic classification levels of SL-2, SL-1, and SL-0 and theassumedseismichazardcurves,thefollowingseismicspecificationsarederived:IAEA level Return Period(years)Peak*Ground Acc.SL-2 50% tileSL-1 50% tileSL-0104102short**0.20.050.05* PeakGroundAccelerationisforbothhorizontalandverticalcomponentsin units of the gravitational acceleration, g.** Theseismicspecificationsarenotderivedprobabilistically-local(uniform) building codes are applied to this class.A peak value of 0.05 gis assumed equal to the SL-1 peak value.Bases Safetyassessmentsofexternalaccidentinitiatorsforfacilities,particularlywhenframedinaprobabilisticriskapproach,maybedominatedbyseismicevents.AssumedseismichazardcurvesareusedinaprobabilisticapproachwhichisconsistentwithIAEArecommendationsforclassificationasaITER Technical BasisG A0 SP 2 01-06-01 R2.0Plant Design Specification Page 29function of return period. The selection of the assumed seismic hazard curve isrelevant to regions of low to moderate seismic activity. Prior to site selection,specificationofthepeakhorizontalandverticalgroundaccelerationprovidetheITERdesignersguidelinesaccordingtothemethodologytobeusedforseismicanalysis,whichwillrelyonaspecifiedGroundMotionDesignResponseSpectrumandasuperpositionofmodalresponsesofthestructures(according to NRC recommendations).After site selection the actual seismicspecifications will be used to adjust the design, in particular by adding seismicisolation, if necessary.6. Meteorological CharacteristicsAssumption Ageneralsetofmeteorologicalconditionsareassumedfordesignofbuildings, civil structures and outdoor equipment, as follows: Maximum Steady, Horizontal Wind 140 km/h (at 10 m elevation) Maximum Air Temperature 35 C (24 hr average 30 C) Minimum Air Temperature -25 C (24 hr average -15 C)MaximumRel.Humidity(24hraverage)95%(correspondingvapourpressure 22 mbar)MaximumRel.Humidity(30dayaverage)90%(correspondingvapourpressure 18 mbar) Barometric Pressure - Sea Level to 500 m Maximum Snow Load - 150 kg/m2 Maximum Icing - 10 mm Maximum 24 hr Rainfall - 20 cm Maximum 1 hr Rainfall - 5 cm Heavy Air Pollution (Level 3 according to IEC-71-21)Bases The assumed meteorological data are used as design inputs.These data do notcompriseacompleteset,butrathertheextremeswhicharelikelytodefinestructuralorequipmentlimits.Ifintermediatemeteorologicaldataarerequired, the designer estimates these data based on the extremes listed above.Steady winds apply a static load on all buildings and outdoor equipment.B. Heat Sink: Water Supply for the Heat Rejection SystemAssumptionTheJCThasselectedforceddraft(mechanical)coolingtowersasadesignsolutionuntiltheITERsiteisselected.At30%pulsedutycycle(450MWaverageheatrejection)thetotalfresh("raw")waterrequirementisabout16 m3/minute.Thiswatermakesupevaporativelossesandprovidesreplacementforblowdownusedtoreducetheaccumulationofdissolvedandparticulate contaminants in the circulating water system.During periods of nopulsing the water requirement would drop to about 5 m3/minute.Eachblowdownactionwillleadtoapeakindustrialsewagerateof3000 m3/day.Bases The actual ITER Site could use a number of different methods to provide theheatsinkforITER,butforthepurposesofthesitenon-specificdesign,the

1 Insulation Co-ordination Part 2 Application Guide, Provisional Scale of Natural Pollution LevelsITER Technical BasisG A0 SP 2 01-06-01 R2.0Plant Design Specification Page 30induced draft (mechanical) cooling towers have been assumed.These coolingtowers require significant quantities of fresh water ("raw") for their operation.For 450 MW average dissipation, approximately 16 m3/minute of the water islost by evaporation and drift of water droplets entrained in the air plume, andbyblowdown.Thiswateralsosuppliesmakeuptothestoragetanksforthefireprotectionsystemaftertheinitialwaterinventoryisdepleted.Coolingtowers may not be suitable for an ITER site on a seacoast or near a large, coolbodyoffreshwater.Thereforeopencyclecoolingwillbeconsideredasadesign option.C. Energy and Electrical Power1. Electrical Power Reliability during OperationAssumption The grid supply to the Steady State and to the Pulsed switchyards is assumedto have the following characteristics with respect to reliability:Single Phase Faults - a few tens/year 80%: t < 1 s- a few / year20%: 1 s < t < 5 minwhere t = duration of faultThree Phase Faults- a few/yearBases ITER power supplies have a direct bearing on equipment availability which isrequiredfortokamakoperation.Ifoperationofsupportsystemssuchasthecryoplant,TFcoilsuppliesandotherkeyequipmentareinterruptedbyfrequentorextendedpoweroutages,thetimerequiredtorecovertonormaloperating conditions is so lengthy that availability goals for the tokamak maynotbeachieved.Emergencypowersuppliesarebasedonthesepowerreliability and operational assumptions.2. ITER Plant Pulsed Electrical SupplyAssumption AhighvoltagelinesuppliestheITER"pulsedloads".Thefollowingtableshows the "pulsed load" parameters for the ITER Site:CharacteristicValuesPeak Active Power*,#500 MWPeak Reactive Power 400 MvarPower Derivative* 200MW/sPower Steps* 60MW Fault Level 10-25 GVAPulse Repetition time 1800 sPulsed Power Duration** 1000 s#from which up to 400 MW is a quasi-steady-state load during the sustainedburnphase,whiletheremaining80120MWhasessentiallypulsecharacterforplasmashapecontrolwithamaximumpulsedurationof5 10 s and an energy content in the range of 250 500 MJ.ITER Technical BasisG A0 SP 2 01-06-01 R2.0Plant Design Specification Page 31* Thesepowerparametersaretobeconsideredbothpositiveandnegative.Positive refers to power from the grid, while negative refers to power to thegrid.Powervariationswillremainwithinthelimitsgivenaboveforthemaximum power and for the power derivatives.** Thecapabilitytoincreasethepulsepowerdurationto3600sisalsoassumed,inwhichcasetherepetitiontimewouldincreaseaccordinglytomaintain the same duty factor.Bases Thepeakactivepower,thepeakreactivepowerandthepowerstepsquotedaboveareevaluatedfromscenariosunderstudy.Occasionalpowerstepsarepresentinthepowerwaveform.Thesupplylineforpulsedoperationwilldemand a very "stiff" node on the grid to meet the assumption.D. Transport and ShippingBases SeveralmodesoftransportandshippingareassumedforITERbecausethediversityofthesemodesprovidesprotectionagainstdisruptionsfortimelydeliveryofmaterialsandequipmentneededbytheproject.Theassumptionsfor transport and shipping are based on some general considerations which arecommon for all modes.Whentheassumptionsdescribethesiteashaving"access"toamodeoftransportorshipping,itmeansthatthesiteisnotsofarawayfromthetransport that the assumed mode would be impractical.Air transport is a goodexample,becauseiftheairportisnotwithinreasonablecommutingtime,thetime advantage of this mode would be lost (i.e. it would become impractical).1. Highway TransportAssumption The ITER Site is accessible by a major highway which connects to major portsof entry and other centers of commerce.2. Air TransportAssumption TheITERSiteislocatedwithinreasonablecommutingtimefromanairportwith connections to international air service.3. Rail and Waterway TransportAssumption It is assumed the ITER site will have rail and waterway access.The railway isassumed to connect to major manufacturing centres and ports of entry.E. External Hazards and Accident Initiators1. External HazardsAssumption It is assumed the ITER Site is not subject to significant industrial and otherman-made hazards.ITER Technical BasisG A0 SP 2 01-06-01 R2.0Plant Design Specification Page 32Bases Externalhazards,ifpresentattheITERsite,mustberecognisedinsafety,operational and environmental analyses.If these hazards present a significantrisk,mitigatingactionsmustbetakentoensureacceptablelevelsofpublicsafety and financial risk.2. External (Natural) Accident InitiatorsAssumption ItisassumedtheITERSiteisnotsubjecttohorizontalwindsgreaterthan140 km/hr (at an elevation of 10 m) or tornadic winds greater than 200 km/hr.TheITERSiteisnotsubjecttofloodingfromstreams,rivers,seawaterinundation,orsuddenrunofffromheavyrainfallorsnow/icemelting(flashflood).Allotherexternalaccidentinitiatorsexceptseismiceventsareassumed below regulatory consideration.Bases The wind speeds specified in this requirement are typical of a low to moderaterisksite.Tornadicwindsapplydynamicloadsofshortdurationtobuildingsand outdoor equipment by propelling objects at high speeds creating an impactinstead of a steady load. The design engineer uses the tornadic wind speed inmodelingadesignbasisprojectilewhichisassumedtobepropelledbythetornado.This design basis is important for buildings and structures that mustcontainhazardousorradioactivematerialsormustprotectequipmentwithacritical safety function.ITER is an electrically intensive plant, which would complicate recovery fromflooded conditions.This assumption does not address heavy rainfall or wateraccumulationthatcanbedivertedbytypicalstormwatermitigationsystems.Forthepurposesofthisassumption,accidentsinvolvingfire,floodingandotherinitiatorsoriginatingwithintheITERplantoritssupportfacilitiesarenot considered external accident initiators.F. InfrastructureBases TheITERProjectissufficientlylargeandextendedindurationthatinfrastructurewillhaveasignificantimpactontheoutcome.Industrial,workforceandsocioeconomicinfrastructureassumptionsarenotquantitativelystatedbecausethereareavarietyofwaystheseneedscanbemet.The assumptions are fulfilled if the actual ITER site and its surroundingregion already meets the infrastructure needs for a plant with similar technical,material and schedule needs as ITER requires.1. IndustrialAssumption ItisassumedtheITERSitehasaccesstotheindustrialinfrastructurethatwouldtypicallyberequiredtobuildandoperatealarge,complexindustrialplant.Industrialinfrastructureincludesscientificandengineeringresources,manufacturing capacity and materials for construction.It is assumed the ITERSite location does not adversely impactthe construction cost and time periodnor does it slow down operation.The following are examples of the specificinfrastructure items assumed to be available in the region of the site:Unskilled and skilled construction labourITER Technical BasisG A0 SP 2 01-06-01 R2.0Plant Design Specification Page 33Facilities or space for temporary construction labourFire Protection Station to supplement on-site fire brigadeMedical facilities for emergency and health careContractors for site engineering and scientific servicesBulk concrete materials (cement, sand, aggregate)Bulk steel (rebar, beams, trusses)Materials for concrete formsConstruction heavy equipmentOff-site hazardous waste storage and disposal facilitiesIndustrial solid waste disposal facilitiesOff-site laboratories for non-radioactive sample analysisBases Efficiencyduringconstructionandoperationofalarge,complexindustrialfacility varies significantly depending on the relative accessibility of industrialinfrastructure.Accessibilitytoinfrastructurecanbedemonstratedbycomparable plants operating in the general region of the site.2. WorkforceAssumption It is assumed that a competent operating and scientific workforce for the ITERPlantcanberecruitedfromneighbouringcommunitiesortheworkforcecanbe recruited elsewhere and relocated to the neighbouring communities.ItisalsoassumedthatITERhasthecapabilityforconductingexperimentsfrom remote locations elsewhere in the world.These remote locations wouldenable"real-time"interactionintheconductoftheexperiments,whileretainingmachinecontrolandsafetyresponsibilitiesattheITERSiteControlFacility.Bases Theworkforcetooperate,maintainandsupportITERwillrequireseveralhundred workers.The scientific workforce to conduct the ITER experimentalprogramwillalsorequireseveralhundredscientistsandengineers.Theassumptionthattheseworkersandscientist/engineerscomefromneighbouring communities is consistent with the site layout plans which haveno provisions for on-site dormitories or other housing for plant personnel. AsignificantscientificworkforcemustbelocatedattheITERSiteasindicatedintheAssumptions.However,thisstaffcanbegreatlyaugmentedandtheexperimentalvalueofITERcanbesignificantlyenhancedifremoteexperimentalcapabilityisprovided.Theresultoftheremoteexperimentisthatscientificstaffsaroundtheworldcouldparticipateinthescientificexploitation of ITER without the necessity of relocation to the ITER Site.RemoteexperimentalcapabilityisjudgedtobefeasiblebythetimeofITERoperationbecauseofadvancesinthespeedandvolumeofelectronicdatatransfers that are foreseen in the near future.ITER Technical BasisG A0 SP 2 01-06-01 R2.0Plant Design Specification Page 343. Socioeconomic InfrastructureAssumption TheITERSiteisassumedtohaveneighbouringcommunitieswhichprovidesocioeconomicinfrastructure.Neighbouringcommunitiesareassumedtobenotgreaterthan50kmfromthesite,oronehourtravel.Examplesofsocioeconomic infrastructure are described in the following list: Dwellings (Homes, Apartments, Dormitories) International Schools from Kindergarten to Secondary School Hospitals and Clinics Job Opportunities for Spouses and other Relatives of ITER workers Cultural life in a cosmopolitan environmentBases Over the life of the ITER plant, thousands of workers, scientists, engineers andtheirfamilieswillrelocatetemporarilyorpermanentlytothecommunitiessurroundingtheITERsite.ThesepeoplecouldcompriseallthenationalitiesrepresentedbytheParties.This"world"communitywillpresentspecialchallenges and opportunities to the host site communities.To attract a competent international workforce, international schools should beprovided.Teachingshouldbepartiallyinthemothertonguefollowingprogrammeswhicharecompatiblewithschoolsineachstudent'scountryoforigin.Allpartiesshouldassistwiththeinternationalschoolsservingthesestudents.Thelistofexamplesisnotintendedtobecompletebutitdoesillustratethefeaturesconsideredmostimportant.Theassumed50kmdistanceshouldmaintain reasonable commuting times less than one hour for workers and theirrelatives.G. Regulations and Decommissioning1. General DecommissioningAssumption Duringthefirstphaseofdecommissioning,theITERoperationsorganizationplacestheplantinasafe,stablecondition.Dismantlingmaytakeplacedecades after the "deactivation" phase.Dismantling of ITER is assumed to betheresponsibilityofaneworganizationwithinthehostcountry.TheITERoperations organization will provide the new organization all records, "as-builtprints",informationandequipmentpertinenttodecommissioning.Plantcharacterizationwillalsobeprovidedfordismantlingpurposesafter"deactivation".Bases Experienceandinternationalguidelines(IAEASafetySeriesNo.74,1986,SafetyinDecommissioningofResearchReactors)stresstheimportanceofgoodrecordkeepingbytheoperationsorganizationasakeytodecommissioning success.ITER Technical BasisG A0 SP 2 01-06-01 R2.0Plant Design Specification Page 352. ITER Plant "Deactivation" Scope of WorkAssumption TheITERoperationsorganizationwilldevelopaplantoputtheplantinasafe, stable condition while it awaits dismantling.ResidualtritiumpresentattheendofITERoperationswillbestabilisedorrecovered to secure storage and/or shipping containers.Residual mobile activation products and hazardous materials present at the endofITERoperationswillbestabilisedorrecoveredtosecurestorageand/orshippingcontainerssuchthattheycanbeshippedtoarepositoryassoonaspractical.ITER deactivation will include the removal of in-vessel components and theirpackaging in view of long-term storage. This removal from the vacuum vesselwill be done by personnel and remote handling tools, trained for maintenanceduring the previous normal operation.Liquids used in ITER systems may contain activation products, which must beremoved before they can be released to the environment or solidified as waste.It is assumed that all liquids will be rendered to a safe, stable form during the"deactivation" phase, and afterwards no more cooling will be necessaryITER"deactivation"willprovidecorrosionprotectionforcomponentswhichare vulnerable to corrosion during the storage and dismantling period, if suchcorrosionwouldleadtospreadofcontaminationorpresentunacceptablehazards to the public or workers.Bases Itisrecommended(IAEASafetySeriesNo.74,1986)thatallradioactivematerialsberenderedintoasafeandstableconditionassoonaspracticalafter the cessation of operations.H. Construction PhaseGeneralrequirementsfortheconstructionphase(exceptland)areverydependentonlocalpractice.However,water,sewageandpowersuppliesneedtobeprovidedatthesiteforaconstructionworkforceofupto3000people.ITER Technical Basis G A0 FDR 1 01-07-13 R1.0ITERPlant Description DocumentITER Technical Basis G A0 FDR 1 01-07-13 R1.0Plant Description Document Table of Contents1. Overview & Summary2. Plant Description: Tokamak Systems Design & Assessment2.1 Magnets2.2 Vacuum Vessel2.3 Blanket2.4 Divertor2.5 Additional Heating and Current Drive2.6 Plasma Diagnostic System2.7 Vacuum Pumping & Fuelling2.8 Cryostat, Vacuum Vessel Suppression System, and Thermal Shields2.9 Remote Handling2.10 Assembly Equipment and Procedures2.11 ITER Decommissioning Procedures2.12 Mechanical Loads and Machine Supports Configuration2.13 Materials Assessment2.14 Nuclear Assessment2.15 Tokamak Seismic Analysis3. Plant Description: Plant Systems Design & Assessment3.1 Tritium Plant & Detritiation3.2 Cryoplant and Cryodistribution3.3 Cooling Water3.4 Pulsed and Steady State Power Supplies3.5 Miscellaneous Plant Systems3.6 Site Layout and Buildings3.7 Plant Control4. Plasma Performance5. Safety6. Plans7. ResourcesITER Technical Basis G A0 FDR 1 01-07-13 R1.0Plant Description DocumentChapter 1 Page 11 Overview & Summary1.1 Introduction ......................................................................................................................... 31.1.1 Preface ........................................................................................................................................ 31.1.2 Evolution of the ITER Design.................................................................................................... 61.1.3 Guidelines and Objectives.......................................................................................................... 71.1.4 Modeling of Design Alternatives ............................................................................................... 91.1.5 Convergence to an Outline Design............................................................................................. 91.1.6 Conclusion................................................................................................................................ 101.2 Design Overview................................................................................................................ 111.2.1 Design....................................................................................................................................... 111.2.2 Operation Scenarios and Phases............................................................................................... 181.3 Plasma Performance ......................................................................................................... 201.3.1 ITER Plasma Current and Size...................................................................................