COMMISSION STAFF WORKING DOCUMENT Commission Staff Working Document Accompanying the document Report from the Commission to the Council and the European Parliament "Operation of the High Flux Reactor in the years 2014-15"
Date: 2018-02-27
Institutions: European Commission, Joint Research Centre
Subjects: EU research policy, Netherlands, North Holland, nuclear reactor, nuclear research, nuclear safety, nuclear technology, research programme

EN 

  EN 

   EUROPEAN COMMISSION  Brussels, 27.2.2018  SWD(2018) 46 final  COMMISSION STAFF WORKING DOCUMENT Commission Staff Working Document Accompanying the document Report from the Commission to the Council and the European Parliament "Operation of the High Flux Reactor in the years 2014-15" {COM(2018) 76 final}  
 
 
COMMISSION STAFF WORKING DOCUMENT 

Accompanying the Report from the Commission to the Council and the European 
Parliament ‘Operation of the high flux reactor in the years 2014-15’ 

This  staff  working  document  is  a  companion  document  to  the  Commission’s  report  on 
‘Operation of the high flux reactor in the years 2014-15’, sent to the Council and the European 
Parliament. 

The high flux reactor (HFR), located in Petten (The Netherlands), is one of the most powerful 
multi-purpose  materials-testing  reactors in  the world.  The reactor is  of  the  tank-in-pool  type, 
light  water  cooled,  moderated  and  operated  at  45  MW.  In  operation  since  1961,  the  reactor 
provides a variety of irradiation location possibilities (reactor core, reflector region and in the 
poolside).  Horizontal  beam  tubes  are  available  for  research  with  neutrons  as  well  as  gamma 
irradiation facilities. Furthermore, fully equipped on-site hot cell laboratories make it possible 
to carry out post irradiation examinations (PIEs). 

The close cooperation between the European Commission Joint Research Centre (JRC) and the 
NRG  has  led  to  a  unique  system  of  managing  the  HFR,  involving  both  organisations.  The 
European  Atomic  Energy  Community  (Euratom)  owns  the  plant  (which  is  leased  from  the 
Dutch  state  for  99  years)  but  is  operated  by  the  Dutch  Nuclear  Research  and  Consultancy 
Group (NRG). As of February 2005, the NRG has become the holder of the operation licence 
granted under the Dutch Nuclear Energy Law. 

Over  the  last  three  decades,  the  HFR  has  been  operated  and  partly  financed  through 
supplementary  research  programmes  which  were  regularly  discussed  and  unanimously 
approved  by  the  European  Council  on  the  basis  of  Article  7  of  Euratom  Treaty.  On  13 
November  2012,  the  Council  adopted  a  four-year  (2012-15)  supplementary  research 
programme for the HFR (Council Decision 2012/709/Euratom — OJ L321/59, 20.12.2012), to 
be implemented by the JRC. 

This document reports on the results of the scientific and technical work carried out in 2014-
15.  It  also  provides  information  on  the  financial  contributions  received for  implementing  the 
programme  and  the  annual  contribution  to  the  decommissioning  fund  provided  by  the 
supplementary research programme. 

1. 

HFR: REACTOR MANAGEMENT 

The  HFR’s  operating  licence  for  the  reporting  period  was  granted  by  the  Dutch  national 
regulator, the Kernfysische Dienst. 

1.1. 

HFR safety, operation and related services 

Operating schedule 

2014 

The HFR returned to service in February 2014 after an unplanned shutdown period of about 4 
months.  In  2014  the  regular  cycle  pattern  consisted  of  a  scheduled  number  of  216  operation 
days,  regular  4-day  reactor  stops  and  a  larger  shutdown  period  of  65  days  in  October  and 
November.  This  corresponds  to  an  actual  availability  of  almost  100%  with  reference  to  the 
original scheduled operation plan. Nominal power has been 45 MW. 

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During the reporting period, the annual 30 MW reactor training for the operators and the yearly 
flux measurements have been carried out in December 2014. 

2015 
The HFR was scheduled to operate for 9 cycles in 2015. Planned full power days were 271 of 
which 230 were realized. The main cause for the lost full power days was the cancellation of 
cycle  2015-08  in  October.  This  cycle  was  skipped  because  of  a  deviation  in  the  control  rod 
system.  Inspection  and  analyses  revealed  a  marginal  play  in  one  of  the  reactor  control  rods 
used to adjust the reactor power. While this play did not affect the functionality of the control 
rod nor reactor safety in any way, preventively a new procedure for assembly, commissioning 
and maintenance/inspection of the control rods has been developed to avoid such effects in the 
future. This has been included in the safety case which was evaluated by the Reactor Safety 
Committee  and  by  the  ANVS,  the  Dutch  nuclear  regulator  The  ANVS  provided  a  formal 
statement of no objection to reactor restart. The HFR was safely restarted in December 2015. 
Nominal power was 45 MW. During the reporting period the annual 30 MW reactor training 
for the operators and the yearly flux measurements have been carried out as scheduled. 

Maintenance activities 

2014 and 2015 

In  2014  and  2015,  maintenance  activities  consisted  of  the  preventive,  corrective  and 
breakdown  maintenance  of  all  systems,  structures  and  components  (SSC)  of  the  HFR,  as 
described in the annual and long-term maintenance plans. These activities were carried out to 
ensure  the  HFR’s  safe  and  reliable  operation  and  to  prevent  inadvertent  scrams  caused  by 
insufficient maintenance. The following activities were successfully completed: 

 

 

 

 

 

 

Scheduled Regular preventive and corrective maintenance; 

Periodic  leak  testing  of  the  containment  building  as  one  of  the  license  requirements 
(0.02 MPa overpressure for 24 h); 

In Service Inspection of the safety relevant parts of the primary system (reactor vessel, 
the  outlet  reducers,  the  bottom  plug  and  primary  piping  in  the  Primary  Pump 
Building); 

Cleaning of the secondary cooling system; 

Revision of the emergency power diesels 

Two week training for the HFR operator staff. 

Concerning  the  total  discharged  activity  of  noble  gas  and  tritium  in  the  license  limit  is  100 
RE/year. The total discharged activity in 2014 was approximately 13 RE and approximately 11 
RE in 2015. 

2. 

2.1. 

HFR AS A TOOL FOR RESEARCH ON REACTOR MATERIALS AND FUEL CYCLES 

Towards  a  fuel  cycle  with 
PELGRIMM projects 

less  nuclear  waste:  the  FAIRFUELS  AND 

The two closely linked 4-year projects FAIRFUELS (fabrication, irradiation and reprocessing 
of  fuels  and  targets  for  transmutation,  and  PELGRIMM  (pellets  vs  granulates:  irradiation, 
manufacturing  and  modelling)  run  under  the  EURATOM  7th  Framework  Programme  (FP7) 

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indirect  actions.  They  aim  at  a  more  efficient  use  of  fissile  material  in  nuclear  reactors  by 
implementing transmutation. Transmutation provides a way to reduce the volume and hazard 
of  high-level  radioactive  waste  by  recycling  and converting  the  most  long-lived  components 
into  shorter-lived  species.  In  this  way,  the  nuclear  fuel  cycle  can  be  closed  in  a  sustainable 
way, producing less and shorter-lived radioactive waste. 
The  FAIRFUELS  consortium  consists  of  10  European  research  institutes,  universities  and 
industry  representatives.  The  project  started  in  2009  and  is  coordinated  by  the  NRG.  The 
PELGRIMM consortium consists of 12 European research institutes, universities and industry 
representatives.  The  project  started  in  2012  and  is  coordinated  by  the  Centre  d'Etudes 
Atomiques (CEA), France. 
The NRG and the JRC work closely together on the HFR irradiations that are scheduled as part 
of the FAIRFUELS and PELGRIMM projects. 

SPHERE 

The SPHERE irradiation test was planned under the FP7 FAIRFUELS project. SPHERE was 
designed  to  compare  conventional  pellet-type  fuels  with  so-called  sphere-pac  fuels  under 
similar irradiation conditions. The latter have the advantage of an easier, dust free production 
process. Especially when dealing with highly radioactive minor actinides, dust-free production 
processes are essential to reducing the risk of contamination. 
To assess the irradiation performance of sphere-pac  fuels compared  with conventional pellet 
fuel, an americium-containing driver fuel for fast reactors (both in pellet- and sphere-pac form) 
was produced at the JRC in Germany. These fuels are irradiated in the HFR, in a dedicated test 
facility. This is the first irradiation test of this kind, as americium-bearing sphere-pac driving 
fuel has never been irradiated before. 
In 2012, SPHERE’s design was finalised; the fuel was produced by JRC and delivered to NRG 
in  the  summer  of  2012.  The  production,  assembly  and  commissioning  of  the  irradiation 
experiment  was  completed  so  that  SPHERE  was  ready  for  irradiation  as  soon  as  the  HFR 
resumed  operation  in  2013.  The  SPHERE  irradiation  in  the  HFR  core  started  on  28  August 
2013 and lasted for approximately 300 full power days before finishing on 26 April 2015. In 
2014,  after  the  first  irradiation  cycle,  a  neutron  radiograph  was  taken  and  compared  with  a 
neutron  radiograph  made  before  the  irradiation.  The  formation  of  the  expected  fuel 
restructuration  in  the  sphere-pac  could  be  confirmed.  Central  hole  formation  was  clearly 
observed  in  the  sphere-pac  fuel  indicating  initial  central  fuel  temperatures  above  2000°C. 
Pellet fuel only showed cracking, an indication of significantly lower central temperatures. In 
2015, after the cool-down period, dismantling of SPHERE started at the NRG Hot Cell Labs 
for post-irradiation examinations. 

MARINE 

MARINE is planned as part of the FP7 PELGRIMM project. The MARINE experiment was 
designed  to  compare  conventional  pellet-type  fuels  with  the  so-called  sphere-pac  fuels 
described  previously.  The  goal  of  the  MARINE  irradiation  is  to  determine  helium  release 
behaviour  and  fuel  swelling  in  an  element  which  is  representative  of  the  minor  actinide-
bearing blanket material to be used for transmutation in sodium fast reactors (SFR). 
Americium-containing  fuels  will  be  produced  at  the  JRC  and  they  will  be  irradiated  at  the 
HFR in a dedicated test facility. The irradiation will use internal pressure sensors to monitor 

3 

 
 
 
online the production of helium, which is characteristic of this kind of americium-containing 
fuel. The MARINE irradiation is expected to start in early 2015 and will last for approximately 
300 full power days. 
During 2014 the design of MARINE was finalized. Unfortunately, the start of the MARINE 
irradiation had to be significantly delayed until fall 2015, mostly as a consequence of NRG’s 
return to service program and subsequent reorganization of NRG. The fuel was fabricated and 
delivered to Petten. The nuclear analysis was completed; the thermomechanical analysis is on-
going.  The  experiment  will  be  irradiated  in  2016  in  position  H8  of  the  HFR  where  the 
conditions in the blanket of a Sodium Fast Reactor (power, temperature, Helium production) 
can be most closely reproduced. Since the pins of MARINE must be connected to a pressure 
transducer, a detailed document for the assembly and welding in the Actinide Laboratory and 
at ECN had to be prepared. 

2.2. 

Fuel and graphite qualification for high-temperature reactors 

High-temperature  reactors  (HTRs)  are  being  investigated  in  a  number  of  countries  as  a  safe 
and efficient source of energy, in particular for the cogeneration of industrial process heat and 
electricity.  Related  new  demonstration  projects  are  either  in  place  or  planned  in  several 
countries  (e.g.  Japan,  China,  US,  South  Korea)  and  are  the  subject  of  current  R&D  being 
carried out in Europe. The HFR is used in particular for the qualification of fuel and graphite 
which are key to ensuring that this type of reactor performs safely. 

HFR-INET 
The Institute of Nuclear and New Energy Technology (INET) of the Tsinghua University in 
Beijing,  China  is  currently  building  the  Chinese  Modular  High  Temperature  Gas-cooled 
Reactor Demonstration Plant (HTR-PM). The fuel for HTR-PM is produced by INET. INET 
requires  qualification  of  their  fuel  to  support  the  licensing  of  HTR-  PM.  The  HFR-INET 
irradiation  is  the  first  step  in  the  HTR  fuel  qualification  process  for  HTR-PM  and  is  being 
carried out by the NRG. 
The  first  step  in  the  fuel  qualification  (under  operational  conditions)  is  performed  by  NRG. 
Similar  to  earlier  tests  for  related  European  programs,  five  spherical  HTR  fuel  elements 
(‘pebbles’)  are  irradiated  under  controlled  conditions  in  the  HFR,  at  almost  constant  central 
pebble temperature, while fission gas release is measured continuously online using the sweep 
loop facility. This sweep loop facility was developed and in the past used by the JRC and is 
currently  being  used  by  the  NRG.  Fission  gas  release  is  an  important  measure  for  fuel 
performance and quality under operational conditions, and forms an essential part of the fuel 
qualification process. A dedicated irradiation test facility was designed and produced for the 
qualification irradiation process. 
The  irradiation  started  in  September  2012  in  a  high  flux  in-core  position  of  the  HFR  and 
finished on 30 December 2014, when the irradiation targets were met. In 2015, the irradiation 
rig was dismantled, and non-destructive Post Irradiation Examinations (PIE) were performed 
in  the  NRG  Hot  Cells.  This  non-destructive  PIE  consists  of  dimensional  and  weight 
measurements, gamma scanning and visual inspection. 
For the second step of the fuel qualification process, the five HTR pebbles are subjected to a 
heating test at the JRC in Karlsruhe in Germany, in the so-called KÜFA-facility. The heating 
test  is  to  demonstrate  the  integrity  and  proper  performance  of  irradiated  HTR  fuel  under 

4 

 
 
 
 
accident  conditions.  Low  radioactive  release  from  the  pebbles  under  these  conditions  then 
demonstrates the integrity and proper performance of irradiated HTR fuel which is a licensing 
requirement.  In  2015,  the  transport  from  Petten  to  Karlsruhe  was  prepared  with  an  expected 
target date in spring 2016. 

INNOGRAPH-1C 
Graphite is used as a moderator and reflector material in an HTR and is known to first shrink 
and  then  swell  under  irradiation.  This  behaviour  depends  on  temperature,  neutron  dose  and 
graphite grades. An understanding of graphite is required for the proper design of HTRs and to 
enable  the  graphite  manufacturing  industry  to  produce  suitable  graphite  grades  with  stable 
properties over longer periods of time. 
The INNOGRAPH-1C irradiation is performed as part of the FP7 ARCHER project (advanced 
high-temperature  reactors  for  cogeneration  of  heat  and  electricity  R&D).  It  follows  earlier 
irradiation  tests,  and  will  complete  the  data  set  for  different  graphite  grades  at  various 
temperatures, under a range of neutron doses. The experiment is a technical building block for 
nuclear cogeneration using HTRs as an alternative to fossil fuels. 
The  experiment  was  successfully  commissioned  for  irradiation  in  2012.The  irradiation  of  3 
HFR cycles was completed in September 2013. Post-irradiation examination was completed in 
2014.  These  examinations  include  for  instance  irradiation-  induced  dimensional  change, 
dynamic Young’s modulus, and coefficient of thermal expansion. Next to that, a selection of 
specimens  was  used  for  further  examinations  with  optical  microscopy,  electron  microscopy, 
and x-ray diffraction. 

SALIENT 
Molten salt fuel forms have received a significantly growing interest in the past years. NRG 
has  started  a  collaboration  with  JRC  and  the  TU  Delft  with  the  aim  to  develop  molten  salt 
technology  and  investigate  the  feasibility  of  molten  salt  reactors,  under  the  program  name 
LUMOS (Learning to Understand MOlten Salts). 
The first step in the LUMOS program is the preparation and execution of an in-pile irradiation 
test  of  molten  salts,  followed  by  dedicated  post-irradiation  examinations  to  generate 
experimental  data.  This  first  irradiation  is  proposed  under  the  name  SALIENT  (SALt 
Irradiation  and  Examination  of  Nuclide  Trapping).  The  purpose  of  the  SALIENT  irradiation 
can be summarized as follows: 

 

 

 

 

to gain experience in handling and irradiating molten fluoride salts, and in treating the 
associated waste; 

to  confirm  claims  of  high  fission  product  stability  compared  to  oxide  fuel,  in 
particular with respect to Cs and I, which dominated the release of activity during the 
Fukushima accident; 

to assess uptake of Xe and other fission products by the graphite crucibles; 

to measure the size distribution for noble metal particles and develop techniques for 
removing the noble gas and noble metal fission products from the salt mixture; 

In  SALIENT,  4  fluoride  salt  samples  are  to  be  irradiated  in  graphite  crucibles  within  triple 
containment.  Small  metal  specimens  will  be  included  in  some  of  the  crucibles.  In  2015, 
preparations were made for this irradiation which is scheduled to start in the course of 2016 

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2.3.  Materials irradiation 

BLACKSTONE 
The United Kingdom’s EdF Energy operates a fleet of advanced gas cooled reactors (AGRs). 
Graphite  degradation  is  considered  to  be  one  of  the  key  issues  that  determine  the  remaining 
service life of an AGR. Data on graphite’s behaviour at high irradiation doses and weight loss 
is  required  to  make  it  possible  to  predict  and  assess  the  behaviour  of  AGR  graphite  cores 
beyond their currently estimated lifetimes, thus ensuring continued safe operation and lifetime 
extension.  The  BLACKSTONE  irradiations  use  samples  trepanned  from  AGR  core  graphite 
and  subjects  them  to  accelerated  degradation  in  the  HFR.  The  tests  are  designed  to  make  it 
possible to predict the future condition of the AGR graphite with confidence. 
After phase I of BLACKSTONE, which finished in 2012, EdF Energy have successfully used 
this  data  to  support  an  updated  safety  case  for  their  AGR  power  stations,  following  an 
evaluation of the data and methods used by the UK nuclear regulator. In the meantime, phase 
II was also completed, with the irradiation of the two capsules for 12 and 16 irradiation cycles. 
The  first  capsule  was  dismantled  in  late  2012,  with  measurements  being  taken  throughout 
2013. The second capsule was dismantled in February 2014, with measurements being taken 
until  October  2014.  Following  these  successes  a  Phase  III  is  now  planned  with  irradiations 
starting in the second half of 2017. New material that is extracted from AGR power stations 
has been transported and received in the NRG hot cell laboratories to machine specimens and 
perform pre-characterisation 

ACCENT 
The  ACCENT  irradiations  also  use  samples  trepanned  from  AGR  core  graphite  and  apply 
pressure to the sample during irradiation. These tests aim to predict microscopic variation in 
the size of the material, to make it possible to predict the future condition of the AGR graphite 
with confidence. 
Phase  I  of  ACCENT  began  at  the  very  end  of  2012,  with  the  design  and  construction 
completed  in  time  for  the  first  irradiation  of  one  HFR  cycle  in  the  summer  of  2013.  The 
sample  was  dismantled  and  measurements  completed  in  the  autumn  of  2013.  Following  the 
success of Phase I, Phase II began with an irradiation lasting 6 HFR cycles between February 
and August 2014. Post-irradiation characterisation on the specimens was successfully carried 
out in September 2014. 
Phase 3a then followed, taking 4 cycles between March and August 2015. Phase 3b lasted 3 
cycles:  from  December  2015  to  March  2016.  Between  phases,  the  modules  were  dismantled 
and  the  samples  characterised.  The  modular  concept  of  the  experiment  has  allowed  for 
flexibility  in  the  design:  In  Phases  3a  and  3b  a  module  without  bellows  was  added  so  as  to 
allow  previously  stressed  samples  to  be  irradiated  without  load.  This  enabled  the  study  of 
creep recovery in graphite by an irradiation anneal. 

LYRA-10 
The LYRA irradiation rig is used in the framework of the European AMES (Ageing Materials 
and Evaluation Studies) network activities with the main goal of understanding the irradiation 
behaviour of reactor pressure vessel (RPV) steels, thermal annealing efficiency and sensitivity 
to re-irradiation damage. The LYRA-10 experiment carried out in the pool side facility of the 

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HFR consists of the irradiation of different specimen types representative of reactor pressure 
vessel materials, namely model steels, realistic welds and high-nickel welds. The model steels 
are  grouped  into  12  batches  with  the  basic,  typical  composition  of  WWER-1000  and  PWR 
reactor  pressure  vessel  materials  studied  by  the  JRC  to  understand  the  role  and  influence  of 
Nikel, Silicon, Chromium and Manganesen as alloying elements and certain impurities such as 
Carbon and Vanadium on the mechanical properties of steels. The realistic welds are created at 
eight different heats, specially manufactured based on typical WWER-1000 weld composition 
with  variation  of  certain  elements,  such  as  Nikel,  Silicon,  Chromium  and  Manganese.  It  is 
important to investigate the role and synergisms of alloying elements in the radiation-induced 
degradation of RPV welds. 
The LYRA-10 irradiation campaign started in May 2007 and was interrupted due to technical 
problems  several  times;  it  has  so  far  included  six  HFR  cycles  at  an  average  temperature  of 
283 °C.  The  original  plan  included  the  irradiation  of  seven  more  cycles  to  achieve  a  fast 
fluence, but it was decided during the LYRA-10 outage that at least 10 more HFR cycles were 
required to determine whether a ‘late-blooming’ effect occurs in the irradiated materials. ‘Late 
blooming’ is a possibly increased effect on material properties at higher irradiation doses, e.g. 
a  stronger  decrease  of  ductile-to-brittle  transition  temperature  in  materials  which  would  not 
match currently used correlations. 
In  order  to  proceed  with  the  resumption  of  the  LYRA-10  experiment,  a  number  of  actions 
were carried out in 2012 to make the rig fit for irradiation. The experiment should have started 
at  the  end  of  2012  but  due  to  the  HFR  shutdown,  it  was  delayed  into  2013.  In  2013,  it  was 
irradiated  for  two  more  cycles,  for  a  total  of  eight  HFR  cycles  at  an  average  temperature  of 
283 °C. It is planned to continue the irradiation for five more cycles to achieve the fast fluence 
requested. 
The  experiment  is  currently  on  hold.  In  2014,  a  certain  number  of  components  had  to  be 
repaired,  among  them  the  temperature  controller  of  the  heater  to  maintain  stable  irradiation 
conditions. After updating and approval of the safety documentation and related analyses, the 
experiment was approved for restart in the Pool Side Facility of the HFR in the beginning of 
2016. 

2.4. 

Irradiations for fusion technology 

ITER PRIMUS 
In 2005, an experiment was defined with the members of the European Fusion Development 
Agreement  (EFDA)  to  test  thermal  fatigue  of  normal  heat  flux  modules  for  ITER  during 
irradiation. This experiment was planned to take place at the HFR pool side facility position 
for the duration of 22 cycles. It had to be designed in a way so that the stress conditions and 
temperatures  would  reflect  ITER  first  wall  conditions.  Between  2005  and  2007,  multiple 
iterations and adjustments have been made to achieve the ITER conditions. These led to a final 
design in 2008, but could not continue because of an HFR outage. In 2009, the position in the 
HFR  pool  side  facility  was  not  available.  In  2010,  the  Reactor  Safety  Committee  gave  the 
feedback that the thermal cycling in the HFR was not possible due to the intrinsic design of the 
automatic control rod system.  
This issue was discussed with the Joint Undertaking 'Fusion for Energy' (hereinafter F4E) as 
EFDA ceased to exist by end of December 2013 and instead a stagnant in-pile experiment was 
proposed, to achieve 1 dpa in beryllium, and to perform the thermal cycling afterwards in the 
JUDITH facility in Jülich was proposed. 

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To perform this irradiation, a new experiment called PRIMUS was designed. 
In 2012, a new conceptual design was presented by F4E and extensive activation calculations 
showed that the mock ups were too active to be handled in the JUDITH facility. Therefore, a 
proposal  was  made  to  cut  the  steel  back  from  the  mock-ups,  without  jeopardising  the  stress 
conditions on the beryllium/CuCrZr interface. 
This  led  to  a  proposal  which  reduced  the  activation  to  levels  acceptable  for  JUDITH.  The 
mock-ups were sent back to France, where the cutting procedure started. 
In 2013 the adapted first wall mock-ups were delivered by F4E. The stainless steel part on the 
back  of  the  mock-up  was  reduced  by  60 %  to  decrease  the  activation  after  irradiation.  New 
irradiation  design  calculations  were  performed  using  the  new  geometry,  and  the  irradiation 
proposal was drafted.  
In 2014 the conceptual design of the mock- up irradiation was completed and the irradiation 
proposal was sent to the Reactor Safety Committee for information. In this conceptual design 
the  mock-ups  were  be  clamped  between  aluminium  filler  material  to  enhance  dissipation  of 
heat  to  the  primary  coolant  of  the  HFR.  The  irradiation  rig  was  instrumented  with  23 
thermocouples  and  dosimeter  sets  to  register  temperature  and  dose  levels  obtained  during 
irradiation. The irradiation targets were 265°C at the interface of the CuCrZr and Be at a dose 
of 1 dpa. Due to the Return to Service program of NRG the project was delayed until 2015. 
In 2015 the irradiation capsule for the PRIMUS mock-ups was fabricated and assembled and 
the  design  and  safety  report  was  approved  by  the  reactor  safety  committee.  After  the 
irradiation  approval  was  given,  the  irradiation  started  on  20  August  2015.  The  target 
temperatures were met in two cycles conducted in 2015. The other three irradiation cycles will 
be performed in 2016. 

CORONIS 
In  2011,  a  new  project  started  under  F4E,  focusing  on  ITER’s  material  development  and 
characterisation. The project was co-financed by the Dutch Ministry of Economic Affairs and 
F4E and ran from 1 January 2011 to October 2015. 
The  objective  was  to  measure  the  tensile,  fatigue  and  Charpy  impact  properties  of  shielding 
blanket material and shielding blanket joints before and after irradiation to 0.01, 0.1 and 0.7 
dpa at 250 °C. This material is planned to be used in the shielding blanket in ITER because of 
its  high  heat  dissipation.  This  property  could  be  jeopardised  if  the  material  fails  during  its 
operational lifetime in ITER. 
The irradiation was also performed with the Hungarian Institute AEKI, which took care of the 
low level dose irradiation (0.01 dpa). All post irradiation experiments were be performed in the 
NRG Hot Cells.  

In  2013,  the  CORONIS  01  and  CORONIS  02  experiments  were  developed,  assembled  and 
commissioned.  After  filling  with  sodium  in  the  ECN  workshop,  the  experiments  were 
transferred to the HFR for irradiation. 

 

 

CORONIS 01 will be irradiated for one cycle corresponding to 0.1 dpa.  

CORONIS 02 aims to accumulate 0.7 dpa corresponding to a three-cycle irradiation 
in the HFR. 

8 

 
 
 
Both  experiments  are  carried  out  at  a  homogeneous  temperature  of  250 °C.  The  materials  in 
CORONIS 01 and 02 are ones which will be used as heat sink material for ITER’s first wall 
shielding modules.  
In  2014 the irradiation  of CORONIS 01 and 02 was started in  the first  cycle and were fully 
completed  during  the  year.  After  a  cool-down  period  the  rigs  were  transported  to  HCL  for 
dismantling  and  Post  irradiation  testing  of  the  included  specimens.  The  examination  is 
ongoing  

FIWAMO 
In  July  2012,  a  new  contract  was  signed  between  ITER  International  Organization, 
Forschungszentrum Jülich (FZJ) and the NRG for the irradiation and high heat flux testing of 
eight enhanced heat flux first wall modules for ITER. 
The ITER first wall is produced using two technologies, normal heat flux (NHF) for loading 
up to 2 MW/m2 and enhanced heat flux (EHF) for loading up to 5 MW/m2. The plasma-facing 
surface  of  the  first  wall  is  made  of  beryllium  tiles  that  are  joined  to  a  heat  sink  using  hot 
isostatic pressing or brazing. The heat sink is attached to a supporting steel structure. 
The scope of this project is to perform a pre-irradiation screening of the modules, from SWIPP 
(China)  and  NIIEF  (Russia),  irradiation  in  the  HFR  to  0.1  and  0.7  dpa  at  200-250 C  and  to 
perform post irradiation high heat flux testing in the JUDITH facility at FZJ up to 5 MW/m2. 
In 2013, Phase 1 of the contract was concluded with the submission of a final design proposal 
for the irradiation capsule. 
The  mock-ups  consists  of  beryllium  tiles  that  are  joined  to  the  heat  sink  using  hot  isostatic 
pressing or brazing technology. They will be clamped between aluminium blocks to allow for 
radial heat dissipation during irradiation. The interface between the copper and beryllium will 
be held at 225  C. The mock-ups will be irradiated to doses of 0.1 and 0.6 dpa, respectively. 
In 2014 the second phase, did not start due to delayed fabrication of the mock- ups. For this 
second phase of the project, the detailed design will start in 2015 and irradiation is planned for 
2016. 

2.5. 

HFR support for research on the standardisation of materials 

Network on Neutron Techniques Standardisation for Structural Integrity (NeT) 
The European Network on Neutron Techniques Standardisation for Structural Integrity (NeT) 
fosters performance and safety improvements in European nuclear power plants. NeT mainly 
supports progress towards improved understanding and prediction of welding residual stresses 
relevant for the integrity of nuclear power plant components. 
The JRC organises and manages NeT and contributes to the scientific work through neutron 
scattering for residual stress measurement using its beam tube facilities at the HFR. 
The NeT members have met twice in 2014, once at EdF Research near Paris and once at Bilgi 
University, Istanbul, to review the work progress and to agree on the way forward. The NeT 
members have issued a comprehensive overview paper on the activities around the single bead 
on plate weld. A dedicated issue of a scientific journal on NeT Task Group 4 (three beads in a 
slot weld) was prepared; and the first specimens of Task Group 6 on a weld in a Nickel base 
alloy plate have been procured. 
The NeT members have met twice in 2015, once hosted by RATEN ICN/Pitesti in Bucharest 
and once at Helmholtz-Zentrum Berlin, to review the work progress and to agree on the way 

9 

 
 
 
 
forward.  
NeT is currently mainly working on its Task Groups (TGs) 4 and 6. In TG4 residual stresses 
around  a  3  bead  in  a  slot  weld  in  an  austenitic  stainless  steel  plate  have  been  studied,  while 
TG6  deals  with  a  similar  specimen  geometry,  but  with  a  nickel  base  alloy  as  base  material. 
TG4 is already in the process of being summarized, whereas TG6 is still in its early stages. In 
2015, the first experimental and numerical results have been reported. 
The partners in NeT have initiated an activity to compile and document the achievements of 
the Network. In view of the upcoming 15th anniversary of NeT in 2017 it was considered a 
reasonably  well-timed  action.  NeT  has  produced  more  than  60  scientific  papers,  including  a 
dedicated issue of the International Journal of Pressure Vessels and Piping (with another one 
currently in preparation). NeT has contributed to at least  10 PhD theses in  several European 
countries  and,  last  but  not  least,  NeT  output  has  been  included  as  an  example  in  the  weld 
modelling guidelines of the R6 defect assessment procedure. 

Standardisation of the neutron diffraction method for residual stress measurement 
The scientific and engineering community use neutron diffraction as a technique for measuring 
residual stresses in materials and components. Work on the development of a standard for the 
method  has  been  in  progress  for  about  15  years.  The  JRC  has  been  involved  from  the 
beginning with its two dedicated diffractometers at the HFR. An ISO technical specification 
about the method was published in 2005. The activity is now entering its final phase, where 
the method’s technical specification is being upgraded to an international standard. 
In  2012,  negotiations  were  undertaken  with  the  ISO  and  several  national  neutron  beam 
facilities  in  order  to  set  up  a  working  group  that  would  thoroughly  review  the  existing 
specification. 
The new Working Group has been established in 2014 under ISO/TC 135/SC 5 charged with 
the  drafting  of  an  International  Standard  for  the  method  based  on  an  existing  Technical 
Specification.  JRC  has  been  entrusted  with  the  convenorship  of  this  Working  Group  with 
nominated  members  from  the  UK,  Germany,  Greece,  South  Africa  and  Canada  plus  one 
observing member from Japan. The first meeting of the group took place in December 2014 in 
Berlin, Germany. The Working Group is meeting as frequently as possibly in order to keep the 
relatively tight standard ISO timelines. In 2015 eight meetings have taken place, including two 
in-person meetings held in Berlin, and in Grenoble. For 2016, a similar number of meetings is 
envisaged, in order to prepare the draft standard for submission to TC 135/SC 5 before the end 
of the year 2016. 

for 

stress  measurements 

the  Euratom  Framework  Programme  project 

Residual 
MULTIMETAL 
The  members  of  the  MULTIMETAL  project  jointly  embarked  on  the  advancement  of 
knowledge  in  the  area  of  integrity  assessment  of  bimetallic  welds  for  nuclear  applications. 
Three  different  components  have  been  studied  in  the  programme;  and  sections  from  two  of 
these components have been at the HFR in 2014 for residual stress measurements by neutron 
diffraction.  Mock-up  no.  3  is  40  mm  thick  and  comprises  a  ferritic  steel  plate  welded  to  an 
austenitic stainless steel plate using austenitic stainless steel consumables. The materials used 
are Russian grade steels, as this specimen is representative of a VVER type reactor. Mock-up 
2  is  a  short  section,  29  mm  long,  of  a  bi-metallic  weld  representative  of  a  PWR  reactor  of 
French  origin.  While  these  two  specimens  were  made  from  similar  materials,  the  welding 

10 

 
 
 
 
geometries and restraint conditions during manufacturing were quite different. Therefore, the 
residual stress results were going to be different and the first data obtained indicated this to a 
certain extent. 
Measurements have continued in 2015, whereby several repeat measurements have been made 
in the ferritic steel part of the component. In these repeat measurements long counting times of 
up to 15 hours have been used in order to reduce the scatter in the data previously observed.. 
The experts from Bay-Logi in Hungary have in the meantime undertaken the first comparison 
of  the  measured  results  with  their  numerical  predictions  and  have  found  a  relatively  good 
agreement already with the first attempts. 
The measurements will continue in 2016 on the austenitic side of the component after repair of 
the neutron monochromator at the HFR neutron beam. 

ISOTOPE PRODUCTION 

isotopes 

to  mainly 

these  medical 

Worldwide, approximately 25.000 patients per day depend on medical radio-isotopes produced 
in the HFR in Petten for diagnosis and therapy. 
NRG  delivers 
radio-pharmaceutical  companies. 
Molybdenum-99  is  by  far  the  most  important  of  these  isotopes.  It  is  a  precursor  of 
Technetium-99m  which  represents  the  most  widely  used  medical  isotope  for  imaging, 
accounting  for  80%  of  nuclear  diagnostic  procedures.  It  performs  a  critical  role  in  the 
diagnosis of heart disease, and is also used in cancer diagnosis through bone and organ scans. 
In  addition,  new  treatment  methods  are  being  developed  thus  leading  to  ever  increasing 
demand for (new) isotopes. Given the half-life of the produced isotopes and the high demand 
for treatment, a well-oiled just-in-time logistic infrastructure is essential. 
The Dutch expertise from NRG, URENCO and TU Delft in the area of medical radioisotopes 
has  been  recently  bundled  into  the  association  "Dutch  Isotope  Valley"  (DIVA)  where 
knowledge,  skills,  capacity  and  alternative  production  methods  for  (medical)  isotopes  have 
attained  sufficient  weight  to  serve  the  world  market.  Considering  that  the  NRU  reactor  at 
Chalk River, Canada will stop routine production of Mo-99 in 2016 and will is planned to be 
shut down in 2018 and that Canada will concentrate on domestic demand as opposed to export, 
this represents an excellent opportunity for DIVA to fill the production gap. 
In order to carry out the asset integrity program which is a prerequisite to run the HFR and its 
ancillary installations until 2024, the Dutch government has granted NRG a loan (through its 
parent company ECN). In parallel, NRG has successfully increased prices for its entire service 
package  and  these  were  accepted  by  all  customers.  In  particular,  NRG's  top  6  isotope 
customers  have  expressed  their  confidence  in  NRG  through  signing  long-term  supply 
agreements. This was a successful step into the direction of financial robustness and viability. 
In  2014,  the  HFR  restarted  its  operation  on  14  February  and  has  performed  its  production 
schedule as planned during the rest of the year. The HFR was thus back on the international 
scene as one of the major producers of medical isotopes worldwide. In 2015, the HFR missed 
one production cycle in October but could be restarted in December. 

11 

 
 
 
FINANCIAL CONTRIBUTIONS TO THE PROGRAMME’S IMPLEMENTATION 

In 2014-15, the following financial contributions were received from Member States for the 
implementation of the supplementary programme: 

 

 

 

Belgium: EUR 300 000 (2014) + EUR 300 000 (2015), 

France: EUR 300 000 (2014) + EUR 300 000 (2015), 

The Netherlands: EUR 7 250 000 (2014) + EUR 7 250 000 (2014), 

for  a  total  of  EUR  15 700 000.  Note  that  these  contributions  cover  the  expenses  specified 
under Annex II of Council Decision 2012/709/Euratom. The Commission does not cover any 
operational deficits, including potential costs of maintenance or repair. 

Since 2004, due to a re-evaluation of decommissioning costs, the annual contribution  of the 
supplementary programme to the decommissioning fund increased from EUR 400 000/year to 
EUR  800 000/year.  This  amount  is  taken  from  (a)  the  regular  budget  of  the  supplementary 
research programme and (b) the interest earned on the bank account of the decommissioning 
fund of the supplementary research programme. For example, in 2014 the estimated amount 
of interest generated by the decommissioning fund was EUR 145 000. Therefore, only EUR 
655 000 was added from the regular supplementary research programme budget to reach the 
EUR 800 000/year. The total amount in the decommissioning fund is EUR 17 239 000. This 
fund  will  contribute  to  the  future  decommissioning  costs  of  the  HFR  (to  be  borne  by 
Euratom), estimated at EUR 72 600 000 in the most recent decommissioning study available.1 

Other  expenditure  incurred  by  the  JRC  during  the  reporting  period  and  paid  from  the 
supplementary research programme budget includes: 

 

 

 

 

1 

direct  staff  costs  (e.g.  HFR  supplementary  research  program  management):  EUR 
257 000 

HFR support costs (e.g. legal advice): EUR 166 000 

utilities (e.g. electricity, water, heating): EUR 1040 000 

spent fuel management costs: EUR 2 450 000 

from 

the  Commission 

Communication 
the  European  Parliament  on 
Decommissioning  of  Nuclear  Installations  and  Management  of  Radioactive  Waste:  Management  of 
Nuclear Liabilities arising out of the Activities of the Joint Research Centre (JRC) carried out under the 
Euratom Treaty — COM(2013) 734 final. 

the  Council  and 

to 

12 

 
 
                                                            
Glossary and Acronyms 

AIPES 

Association of Imaging Producers and Equipment Suppliers 

ARCHER 

Advanced High-Temperature Reactors for Cogeneration of Heat and Electricity R&D 

dpa 

displacements per atom 

Euratom 

European Atomic Energy Community 

FAIRFUELS 

Fabrication, Irradiation and Reprocessing of FUELS and target for transmutation 

F4E 

HFR 

IAEA 

INET 

ISO 

ITER 

JRC 

MA 

Fusion  for  Energy  (the  European  Union’s  Joint  Undertaking  for  ITER  and  the  
development of fusion energy) 

High Flux Reactor 

International Atomic Energy Agency 

Institute for Nuclear and New Energy Technology (Tsinghua University Beijing, China) 

International Organisation for Standardisation 

International Thermonuclear Experimental Reactor 

Joint Research Centre 

Minor Actinides 

MARIOS 

Minor Actinides in Sodium-cooled Fast Reactors 

NeT 

NRG 

EU Network on Neutron Techniques Standardisation for Structural Integrity 

Nuclear Research and consultancy Group 

OECD/NEA 

Organisation for Economic Cooperation and Development / Nuclear Energy Agency 

PELGRIMM 

PELlets versus GRanulates: Irradiation, Manufacturing & Modelling 

PIE 

RE 

Post Irradiation Examination 

1 RE: amount of radioactivity causing a dose of 1 Sv if inhaled or ingested 

13