COMMISSION STAFF WORKING PAPER Accompanying document to the Report "Operation of the High Flux Reactor in the year 2011"
Date: 2013-07-03
Institutions: European Commission
Subjects: EAEC, Joint Research Centre, Netherlands, North Holland, nuclear reactor, nuclear safety, report, research programme

EUROPEAN 
COMMISSION 

Brussels, 3.7.2013  
SWD(2013) 238 final 

COMMISSION STAFF WORKING PAPER 

Accompanying document to the Report "Operation of the High Flux Reactor in the year 
2011" 

{COM(2013) 489 final} 

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COMMISSION STAFF WORKING PAPER 

Accompanying document to the Report "Operation of the High Flux Reactor in the year 
2011" 

1. 

INTRODUCTION 

This staff working document is a companion document to the Report from the Commission to 
the  Council  and  the  European  Parliament  "Operation  of  the  High  Flux  Reactor  in  the  year 
2011". 

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, and 
following  a  new  vessel  replacement  in  1984  and  large  repair  in  2010  on  the  Bottom  Plug 
Liners (BPL), 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,  excellently  equipped  hot  cell 
laboratories on the site provide Post Irradiation Examinations possibilities. 

The European Atomic Energy Community (Euratom) is the owner of the plant (for a lease of 
99  years  from  the  Dutch  state).  The  HFR  is  managed  by  the  European  Commission’s  Joint 
Research Centre (JRC) and operated by the Nuclear Research and Consultancy Group (NRG). 
The close co-operation between the JRC and the NRG on all aspects of nuclear research and 
technology has led to a unique HFR structure, in which both organisations are involved. The 
JRC  is  the  plant  and  budget  manager  and  develops  a  platform  around  HFR  as  a  tool  for 
European  collaborative  programmes,  while  NRG  operates  and  maintains  the  plant  and 
manages the commercial activities around the reactor. Furthermore each organisation provides 
complementary  possibilities  around  the  reactor  activities,  such  as  the  hot  cell  facilities  of 
NRG or the experiment commissioning laboratory of the JRC. 

As of February 2005, NRG has become the holder of the operation licence granted under the 
Dutch Nuclear Energy Law.  

During  the  last  three  decades  the  HFR  has  been  operated  from  supplementary  research 
programmes  regularly  discussed  and  approved  by  the  European  Council.  On  25  May  2009, 
the European Council adopted a three-year (2009-2011) supplementary research programme 
to  be  implemented  by  the  JRC  for  Euratom  concerning  the  operation  of  the  Community’s 
High Flux Reactor.  

The present document reports the results of the implementation of the scientific and technical 
activities  for  the  year  2011.  The  report  also  provides  information  regarding  the  financial 
contributions received for the execution of the programme and the yearly contribution to the 
decommissioning fund that the supplementary research programme provides to Euratom. 

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1. 

HFR: REACTOR MANAGEMENT 

The  HFR  reactor  has  an  operating  licence  granted  by  the  Dutch  national  regulator,  the 
Kernfysische  Dienst.  In  April  2011,  the  HFR  has  been  the  subject  of  an  independent 
INtegrated Safety Assessment for Research Reactors (INSARR) review mission performed by 
the International Atomic Energy Agency (IAEA). 

1.1. 

HFR Safety, Operation and Related Services 

Operating Schedule 

In 2011 the regular cycle pattern consisted of a scheduled number of 293 operation days and 
two  maintenance  periods  of  19  and  16  days  respectively.  The  In-Service  Inspection  of  the 
north and south reducer and the annual leak test of the reactor containment were performed 
during the summer maintenance period in August 2011, which implied a final effective annual 
operation  time  of  the  HFR  of  290  days  (see  Figure  1).  This  performance  corresponds  to  an 
actual availability of 99.22 % with reference to the original scheduled operation plan. 

Nominal power was 45 MW with a total energy production in 2011 of approximately 13,008 
MWd, corresponding to a fuel consumption of about 16.24 kg U-235. The detailed operating 
characteristics are given in Table 1. 

During  the  reporting  period  the  power  distribution  measurements  for  the  FLUX  2011 
programme  was  carried  out.  In  the  framework  of  the  regular  HFR  operators’  training,  the 
annual  30  MW  reactor  training  course  for  the  operators  was  performed  after  the  scheduled 
end of each cycle at 45 MW operation. 

HFR cycle 11.08 was preceded by short runs of reactivity measurements at low power. The 
aim  of  the  measurements  was  to  test  the  reactivity  characteristics  of  two  new  fresh  fuel 
elements. The result of the measurements showed that the characteristics were consistent with 
regular fuel elements and that the elements could be used as test elements in the HFR starting 
with cycle 11.08. 

All details on power interruptions and power disturbances, which occurred in 2011, are given 
in Table 2. This table shows that twelve automatic reactor scrams, two manual reactor shut-
downs and three automatic power decreases occurred (see also figure 2). Two of these scrams 
were due to human intervention while the remaining ones were due to normal intervention by 
the safety protection systems of the reactor instrumentation devices. 

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Figure 1: HFR availability 

120

e
g
a
t
n
e
c
r
e
P

100

16

14

12

80

10

r
e
b
60
m
u
N
40

8

6

4

2

0

20

0

A1: Number of days at
power / (Number of
B1: Number of
days at power +
unplanned reactor
Number of days of
shutdowns initiated by
unscheduled shut-
reactor protection
downs)
system/manual
A2: Number of days at
intervention
B2: Number of
power / 365
unplanned reactor
shutdowns initiated by
experiments under
irradiation

A3: Number of days at
power / scheduled
operating days

B3: Total reactor
shutdowns (B1 + B2)

2002
2003
2002

2003
2004

2004
2005

2005
2006

2006
2008
2007
2007
2009
2008
2010

2009
2011

2010

2011

Year

Year

Figure 2: HFR unscheduled shutdowns 

Maintenance Activities 

In  2011  the  maintenance  activities  consisted  of  the  preventive,  corrective  and  breakdown 
maintenance  of  all  Systems,  Structures  and  Components  of  the  HFR,  as  described  in  the 
annual and long-term maintenance plans. These activities are executed with the objective to 
enable the safe and reliable operation of the HFR and to prevent inadvertent scrams caused by 
insufficient maintenance. 

The  periodic  leak  testing,  as  one  of  the  licence  requirements  (0.5  bars  overpressure  for  48 
hours  duration)  and  the  In-Service  Inspection  of  the  north  and  south  reducers,  were  also 
successfully  performed.  As  part  of  the  HFR  Modification  Plan,  several  modifications  were 
performed (LOCA 4, 5 and 6). All modifications were implemented after the revision of the 
plant  description  and  operating  instructions  and  following  successful  commissioning  and 
testing and licensing approval where necessary. 

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1.2. 

Fuel cycle 

Front end 

During  2011,  50  Low  Enriched  Uranium  (LEU)  fuel  elements  and  15  control  rods  were 
inspected  at  the  manufacturer’s  site  and  delivered  to  Petten.  Since  May  2006,  the  HFR  is 
running completely on LEU fuel. 

Back end 

In  the  first  quarter  of  2011,  the  last  18  High  Enriched  Uranium  (HEU)  spent  fuel  elements 
were shipped in a CASTOR MTR2 container to the storage facility (HABOG) of the Dutch 
Central Organisation for Radioactive Waste (COVRA). Before this shipment, all HEU spent 
fuel  elements  used  in  the  HFR  have  been  either  sent  back  to  the  USA  (between  2005  and 
2006) or are stored in the HABOG. 

Support has also been provided to the “Interfacultair Reactor Instituut” (IRI) of TU Delft in 
the second quarter of 2011 by providing a MTR-2 container and equipment for a transport of 
spent fuel from the Delft research reactor to the HABOG by making available . 

In  the  third  quarter  of  2011,  the  “Gesellschaft  für  Nuklear-Service”  (GNS)  successfully 
carried  out  the  compulsory  3  years  inspection  of  the  MTR2  container  GP-24,  the  6  year 
inspection  of  the  MTR2  container  GP-23,  as  well  as  of  other  transport  and  ancillary 
equipment. 

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Table 1: 2011 operational characteristics 

Cycle 
Begin-End 

2011 

HFR 
Cycle 

Generated  
Energy 

Planned 

MWd 

OPERATING TIME 

SHUT-DOWN TIME 

Low 
Power 

h.min 

Nom. 
Power 

h.min 

272.00 

Other 
Use 

h.min 

Total 

Planned 

Unscheduled 

Number of 
Interruptions 

h.min 

h.min 

h.min 

Power Dec. 

Scram 

272.05 

16.00 

01.01 – 12.01 

11.01 

510.04 

13.01 – 13.02 

11.02 

1291.83 

14.02 – 16.03 

11.03 

1247.90 

17.03 – 17.04 

11.04 

1204.75 

18.04 – 06.05 

07.05 – 05.06 

11.05 

1279.33 

06.06 – 05.07 

11.06 

1201.73 

06.07 – 07.08 

11.07 

1281.66 

hrs 

272 

688 

664 

688 

640 

688 

02.05 

688.41 

690.46 

77.08 

03.16 

666.09 

669.25 

74.25 

04.51 

640.48 

645.39 

74.21 

Maintenance period 

456.00 

02.23 

681.45 

684.08 

35.33 

02.34 

639.17 

641.51 

78.00 

00.06 

00.10 

47.00 

00.19 

00.09 

05.45 

682.16 

688.01 

102.05 

01.54 

08.08 – 23.08 

Maintenance period and ISI inspection reducers 

384.00 

24.08 – 23.09 

11.08 

1239.51 

24.09 – 24.10 

11.09 

1253.50 

25.10 – 27.11 

11.10 

1248.37 

28.11 – 28.12 

11.11 

1232.69 

29.12 – 31.12 

12.01 

16.94 

664 

664 

688 

664 

8 

04.20 

660.19 

664.39 

77.39 

01.42 

02.23 

666.45 

669.08 

74.52 

03.18 

661.05 

664.23 

122.32 

30.05 

01.43 

657.45 

659.28 

84.32 

01.55 

08.45 

10.40 

61.20 

1 

1 

4 

3 

2 

2 

1 

1 

1 

1 

TOTAL : 

13008.27 

7016 

35.52 

6925.35 

6961.27 

1717.08 

81.25 

3 

14 

Percentage of total time in 2011 (8760 h): 

0.41 

79.06 

79.47 

19.60 

0.93 

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DATE  CYCLE  TIME 

OF 

ACTION 

RESTART 
OR 
POWER IN-
CREASE 

NOMINAL/
ORIGINAL
POWER 

Table 2: 2011 full power interruptions of HFR 

ELAPSED TIME TO 

DISTURBANCE CODE 

RESTART  OR 
POWER 
INCREASE 

NOMINAL/ 

1 

2 

3 

ORIGINAL 

MW 

POWER 

h.min 

REACTOR 
SYSTEM 
EXPERIMENT 
CODE 

COMMENTS 

OR 

2011 

hour 

hour 

hour 

h.min 

11 Feb 

11.02 

16.16 

16.22 

16.35 

00.06 

00.13 

AS 

0 

A 

E  Main Power 
interruption 

Main power interruption caused an automatic 
reactor shutdown. 

24 Feb 

11.03 

16.16 

16.22 

16.35 

00.06 

00.13 

AP 

37.5 

R  H  Power demand 

27 Feb 

11.03 

00.33 

00.43 

01.06 

29 Mar 

11.04 

09.42 

08.21 

09.30 

00.10 

46.31 

00.23 

AS 

47.48 

MS 

01 Apr 

11.04 

00.42 

00.51 

01.24 

00.09 

00.33 

AS 

01 Apr 

11.04 

01.33 

01.38 

01.55 

14 Apr  

11.04 

16.04 

16.10 

16.24 

09 May 

11.05 

22.33 

22.38 

23.00 

20 May 

11.05 

11.00 

11.08 

11.24 

31 May 

11.05 

22.33 

22.39 

22.50 

14 Jun 

11.06 

09.21 

09.26 

09.43 

00.06 

00.06 

00.05 

00.08 

00.06 

00.05 

EN 

00.16 

AS 

00.20 

AS 

00.22 

AS 

00.16 

MS 

00.11 

AS 

00.22 

AS 

7 

0 

0 

0 

0 

0 

0 

0 

0 

0 

P 

P 

P 

P 

P 

P 

P 

I  Experiment 354-01 

R  M  Power demand 

P 

I  Experiment 354-01 

I  Experiment 354-01 

I  Experiment 354-01 

I  Experiment 354-01 

A wrong switch was activated so that the reactor 
power demand was not switched on, with as result 
an automatic power decrease. 

Cooling water pressure of experiment 354-01 too 
low with an automatic reactor shut-down as result. 

The control rod could not be moved due to a 
defect in power demand, the reactor was stopped 
manually. 

Cooling water pressure of experiment 354-01 too 
high with an automatic reactor shut-down as 
result. 

Cooling water pressure of experiment 354-01 too 
low with an automatic reactor shut-down as result. 

Cooling water pressure of experiment 354-01 too 
low with an automatic reactor shut-down as result. 

Cooling water pressure of experiment 354-01 too 
low with an automatic reactor shut-down as result. 

I  Experiment 354-01  Manual shut-down for testing the reactor interlock 

I  Experiment 354-01 

I  Experiment 354-01 

settings of cooling water systems of experiment 
354-01.  

Cooling water pressure of experiment 354-01 too 
low with an automatic reactor shut-down as result. 

Cooling water pressure of experiment 354-01 too 
low with an automatic reactor shut-down as result. 

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14 Jun 

11.06 

11.44 

11.48 

12.05 

00.04 

00.21 

AS 

01 Aug 

11.07 

14.18 

14.22 

14.39 

00.04 

00.21 

AS 

07 Aug 

11.07 

06.10 

AS 

0 

0 

0 

02 Sep 

11.08 

11.40 

11.44 

11.48 

00.04 

00.08 

MP 

35 

P 

P 

P 

P 

I  Experiment 354-01 

Cooling water pressure of experiment 354-01 too 
low with an automatic reactor shut-down as result. 

I  Experiment 292-01 

Cooling water pressure of experiment 292-01 too 
high with an automatic reactor shut-down as 
result. 

I  Experiment 354-01 

Cooling water pressure of experiment 354-01 too 
low with an automatic reactor shut-down as result. 

S  Experiment 354-02 

Reactor power temporary decreased to 35 MW to 
check if the production of bubbles in the cooling 
water outlet of Prod. Facility 354-02 depends on 
the reactor power.  

Reactor ventilation stopped due to the failure of a 
relay in the instrumentation. This caused an 
automatic power decrease to 0 MW 

After repair and Xenon decay the reactor was 
restarted on 31 Oct at 03.45 hr. 

29 Oct 

11.10 

22.29 

AP 

0 

R  A  Reactor Ventilation 

31 Oct 

11.10 

03.45 

04.15 

30.01 

00.30 

  Restart  

04 Nov 

11.10 

08.34 

08.38 

09.03 

00.04 

00.25 

AS 

0 

A 

E  Main power 
interruption 

Main power interruption caused an automatic 
reactor shutdown 

1. LEADING TO 

- automatic shut-down 

- manual shut-down 

- automatic power decrease 

- manual power decrease 

AS 

MS 

AP 

MP 

2. RELATED TO 

- reactor 

- experiment 

- auxiliary system 

- production facility 

R 

E 

A 

P 

3. CAUSE 

- scheduled 

- requirements 

- instrumentation 

- mechanical 

- electrical 

- human 

S 

R 

I 

M 

E 

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2. 

INSAAR 2011 

At the request of the Dutch authorities, a full scope IAEA-INSARR mission was performed at 
the  HFR  in  March  2011.  The  general  objectives  of  the  mission  were  to  conduct  a 
comprehensive  safety  review  of  the  HFR  research  reactor  according  to  the  applicable 
documents and IAEA standards. 

The  findings/recommendations  formulated  in  the  previous  IAEA-INSARR  mission  (13-18 
February 2005) and in the 2010 IAEA inspection dedicated to the repair of the BPL were also 
scrutinized,  in  order  to  determine  the  degree  of  implementation  of  the  related  corrective 
actions. The safety areas to be examined in detail were determined in a Pre-INSARR mission 
in January 2011. 

The  INSARR  Team  (3  IAEA  experts  +  5  external  experts)  and  inspectors  of  the  Dutch 
regulatory  body  conducted  the  review  by  means  of  documentation  analyses,  facilities  walk-
through, and observation of the operations and interviews with the personnel. 

The INSARR review concluded that  all  the recommendations/suggestions deriving from the 
safety review  regarding the BPL repair  and  about 50% of those deriving  from the INSARR 
2005 mission have been addressed. The implementation of all the corrective actions will be 
completed in 2012. 

3. 

EU STRESS TESTS  

Following the nuclear disaster in Fukushima, Japan, in March 2011, all of the nuclear power 
plants  in  Europe  were  subject  to  stress  tests.  Although  the  HFR  is  not  a  power  plant,  but  a 
research and isotope production reactor, it was subject of such a stress test on both the reactor 
and on the other nuclear facilities on the nuclear site.  

The stress test investigated the impact of flooding events, earthquakes and extreme weather as 
well  as  events  resulting  from  human  activities  (such  as  explosions,  fires,  malevolence  and 
aircraft  crashes).  NRG  has  employed  the  same  scenarios  as  used  for  nuclear  power  plants, 
which were ‘tailored’ to the specific nature of the facilities in Petten.  

The  results  of  this  test  showed  that  the  nuclear  installations  in  Petten  met  all  of  the  safety-
relevant  licensing  requirements  and  can  also  withstand  a  wide  range  of  extreme  external 
conditions, including flooding and earthquakes or a combination of both.  

The  stress  test  also  showed  that  it  is  feasible  to  increase  even  more  the  safety  margins  by 
taking  a  number  of  measures.  For  example,  measures  that  can  be  taken:  to  install  seismic 
instrumentation  with  notification  in  control  room,  to  make  it  possible  to  rapidly  install  an 
external  generator  for  power  supply  to  vital  reactor  systems;  to  improve  the  anchoring  of 
water  storage  tanks  in  the  event  of  an  earthquake  or  flood;  to  improve  the  autonomy  of  the 
emergency  response  organisation;  to  develop  new  procedures  when  there  is  a  threat  of  a 
serious situation.  

Finally, a number of other identified measures which can be envisaged to increase robustness 
of  the  nuclear  facilities  on  the  HFR  site  will  be  investigated  to  see  whether  any  additional 
measures could contribute to increasing the current safety margins. 

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4. 

HFR AS A TOOL FOR RESEARCH 

4.1. 

Network on Neutron Techniques Standardization for Structural Integrity (NeT) 

The European Network on Neutron Techniques Standardization for Structural Integrity (NeT) 
supports  progress  towards  improved  performance  and  safety  of  European  nuclear  energy 
production  systems.  The  JRC  organises  and  manages  the  Network  and  it  contributes  to  the 
scientific work through the neutron scattering for residual stress measurement and assessment 
of thermal material ageing effects, using its beam tube facilities at the HFR. 

The 19th and 20th Steering Committee Meetings of NeT took place in June and December in 
2011,  respectively.  About  35  organisations  are  actively  participating  in  the  work  of  NeT, 
including eight organisations from the new EU Member States and three organisations from 
candidate countries. From outside the EU, organisations from Japan, Australia and Russia are 
actively contributing to NeT. Furthermore, in 2011 for the first time measurements for NeT 
have been undertaken at the Spallation Neutron Source in Oak Ridge, TN, USA. 

While  the  final  output  documents  of  the  first  Task  Group  of  NeT  are  being  drafted,  a  new 
activity has been defined on residual stress investigations in a welded nickel-base alloy plate. 
Other possible future activities have been under discussion during the year. Furthermore the 
NeT  Task  Group  1  has  been  setting  a  benchmark  for  numerical  and  experimental  work 
available to nuclear engineers throughout the world for testing, in particular, the performance 
of their numerical methods. 

4.2. 

Neutron diffraction investigations at the HFR 

In the reporting period a feasibility study has been undertaken for diffraction measurements in 
the  nickel-base  alloy  that  is  considered  for  the  next  Task  Group  within  NeT.  Nickel  has  a 
considerably higher neutron attenuation coefficient than iron, and in addition it also produces 
a stronger background signal in neutron scattering. These effects result in higher limitations in 
the material thickness that can be covered by neutron diffraction experiments and in the need 
for longer counting times at comparable peak intensity due to the higher background. It was 
therefore  necessary  to  obtain  a  quantitative  estimation  of  the  magnitude  of  the  problems  in 
order to define the geometry of the specimens to be investigated. 

The measurements were undertaken at the Large Component Neutron Diffraction Facility at 
beam  tube  HB4  at  the  HFR.  They  resulted  in  an  estimate  for  the  attenuation  coefficient  of 
0.175  mm-1,  relevant  to  the  particular  nickel-based  alloy  and  relevant  to  the  (111)-
crystallographic  reflection  plane.  As  expected,  this  is  considerably  higher  than  the 
corresponding values observed for iron-based alloys in the past. Based on the findings it was 
concluded that specimens with a thickness of 12 mm could be investigated. Consequently it 
was  decided  at  the  NeT  Steering  Committee  Meeting  in  December  2011  that  specimens  of 
this thickness would be manufactured for the new Task Group. 

5. 

FUEL IRRADIATIONS IN THE HFR 

In  the  frame  of  the  Euratom  7th  Framework  Programme  (FP7),  the  4-year  project 
FAIRFUELS  (Fabrication,  Irradiation  and  Reprocessing  of  FUELS  and  targets  for 
transmutation)  aims  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 the most long-lived components. In this way, the 

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nuclear  fuel  cycle  can  be  closed  in  a  sustainable  manner.  The  FAIRFUELS  consortium 
consists  of ten European  research institutes, universities and industry. The project started in 
2009 and is coordinated by NRG. In 2011, both NRG and JRC continued working together in 
the planning of the HFR irradiations that are scheduled in FAIRFUELS. 

5.1.  MARIOS Fuel Irradiation: Minor Actinide Recycling 

The  MARIOS  irradiation  programme,  as  part  of  FAIRFUELS,  is  a  series  of  irradiations 
dealing  with  heterogeneous  recycling  of  Minor  Actinides  (MAs)  in  sodium-cooled  fast 
reactors  (i.e.  the  MA-bearing  blanket  concept).  Minor  Actinides,  such  as  americium  and 
curium, are long-lived elements in the high level waste, which are currently not recycled. The 
aim  of  the  MARIOS  irradiation  test  is  to  investigate  more  closely  the  behaviour  of  minor 
actinide targets  in  a uranium oxide matrix carrier. In these targets, large amounts of  helium 
are  produced,  which  causes  significant  damage  to  the  material  under  irradiation.  This 
experiment is the first case where americium (241Am) is included in a (natural) uranium oxide 
matrix Am0.15U0.85O1.94 to conduct an experiment in order to study the behaviour in terms of 
helium production and swelling. 

After  having  obtained  the  approval  for  the  irradiation,  the  MARIOS  irradiation  started  as 
planned  on  19  March  2011.  The  test  specifications  of  MARIOS,  in  terms  of  controlled 
working  temperature  of  the  fuel  pellets,  are  very  strict  and  the  first  cycle  showed  a  small 
deviation from that expected. Nevertheless, due to the large operational margins foreseen in 
the design of the experiment, it was possible to successfully correct the deviation already from 
the second cycle. MARIOS will run till 1st April 2012 (approximately 300 days).  

5.2. 

SPHERE Fuel Irradiation: Safer Fuels 

Within the FP7 FAIRFUELS project, the irradiation test SPHERE has been planned for 2012. 
SPHERE has been designed to compare conventional pellet-type fuels with so-called Sphere-
Pac fuels. The latter have the advantage of an easier, dust-free fabrication process. Especially 
when  dealing  with  highly  radioactive  minor  actinides,  dust-free  fabrication  processes  are 
essential to reduce the risk of contamination.  

To  assess  the  irradiation  performance  of  Sphere-Pac  fuels  compared  to  conventional  pellet 
fuel,  a  dedicated  SPHERE  irradiation  experiment  will  be  performed.  For  this  purpose, 
americium-containing  fuel,  both  pellet-type  and  Sphere-Pac-type,  will  be  fabricated  at  JRC. 
These fuels will be irradiated at HFR in a dedicated test-facility. It is the first irradiation test 
of this kind, as Minor Actinides bearing Sphere-Pac fuel has never been irradiated before. The 
SPHERE irradiation should start in 2012 and will last for approximately 300 full power days. 

During  2011,  the  preliminary  design  of  SPHERE  has  been  finalised.  The  fuel  has  been 
fabricated at JRC and some preliminary nuclear analyses have been concluded.  

6. 

MATERIALS IRRADIATIONS 

6.1. 

BLACKSTONE Irradiations: Investigation of AGR Lifetime Extension 

The UK has a fleet of Advanced Gas Cooled Reactors (AGRs). In order to extend the lifetime 
of the AGRs, graphite data at high dose and weight loss is required, to allow prediction and 
assessment of the behaviour of AGR graphite cores beyond their currently estimated lifetimes. 
Graphite  degradation  is  considered  to  be  one  of  the  key  issues  that  will  determine  the 

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remaining life of the AGRs, thus materials property data at extended weight loss and dose is 
essential for continued safe operation and lifetime extension. The BLACKSTONE irradiations 
use samples extracted from AGR core graphite and subjected to accelerated degradation in the 
HFR.  The  results  are  designed  to  enable  the  future  behaviour  of  the  AGR  graphite  to  be 
predicted with confidence. 

The  first  BLACKSTONE  irradiations  were  completed  in  2010  after  achieving  the  required 
weight  loss  and  dose  levels.  In  2010  the  dismantling  of  both  BLACKSTONE  experiments 
took  place  and  the  larger  part  of  the  post  irradiation  examinations  have  been  performed  in 
2011. In the meantime two new irradiations have been designed and built to achieve higher 
dose  and  weight  loss  and  to  irradiate  material  from  different  AGRs.  The  objective  of  these 
experiments  is  to  consolidate  the  database  produced  in  phase  I  and  to  provide  an  extensive 
properties  database  for  graphite  from  the  Hartlepool  and  Heysham  1  AGRs.  These  Phase  II 
experiments were loaded into the HFR core in August 2011 and will be irradiated for a total 
of 11 and 16 monthly cycles respectively. 

6.2. 

LYRA-10 

The  LYRA  irradiation  rig  is  used  in  the  framework  of  the  AMES  (Ageing  Materials  and 
Evaluation  Studies)  European  Network  activities  with  the  main  goal  of  studying  the 
irradiation behaviour of reactor pressure vessel (RPV) steels, thermal annealing efficiency and 
sensibility to re-irradiation damage. 

The LYRA-10 experiment housed in the Pool Side Facility (PSF) of the HFR consists in the 
irradiation  of  different  specimens  representative  of  RPV  materials,  namely  model  steels, 
realistic welds and high-nickel welds. The model steels comprise of 12 batches of steels with 
the  basic,  typical  composition  of  WWER-1000  and  PWR  reactor  pressure  vessel  materials 
used by the JRC with the scope of understanding the role and influence of Ni, Si, Cr and Mn 
as alloying elements and certain impurities as C and V on the mechanical properties of steels. 

The realistic welds are created at eight different heats, specially manufactured on the bases of 
typical WWER-1000 weld composition with variation of certain elements, such as Ni, Si, Cr 
and Mn. They are of importance 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  up  to  now  underwent  6  HFR 
cycles. Originally planned to be irradiated for 7 more cycles, it has been decided during the 
LYRA-10  outage  that  at  least  10  more  cycles  will  be  required  to  allow  the  analysis  of  an 
hypothetically late-blooming effect that may take place in the irradiated materials. 

In order to proceed to the resumption of the LYRA-10 experiment, some mechanical testing 
and  other  revamping  actions  have  taken  place  in  2011.  Hence,  the  LYRA-10  feeding  lines 
(which  form  part  of  the  gas  panels  to  the  connection  set  next  to  the  pool)  were  adapted 
following  the  change  in  the  HFR  glove  box  system.  The  experiment  connection  head  was 
completely renewed (i.e. removal of the plastic hose, gas lines, etc.) and commissioned. Most 
of  the  still-pending  technical  issues  were  resolved  in  2011  and  LYRA-10  is  expected  to  be 
irradiated again in the PSF in 2012. 

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7. 

IRRADIATION FOR FUSION REACTOR TECHNOLOGY 

7.1. 

CORONIS 

In  2011  a  new  project  started  in  the  area  for  material  development  and  characterisation  for 
ITER.  This  project  is  conducted  in  the  framework  of  Fusion  for  Energy,  the  Europe  Joint 
Undertaking for fusion energy, founded in 2007. 

The  objective  is  to  measure  the  tensile,  fatigue  and  Charpy  impact  properties  of  CuCrZr 
material and CuCrZr/316L joints before and after irradiation to 0.01, 0.1 and 0.7 dpa at 250 
ºC. This material is foreseen in the shielding blanket in ITER due to the high heat dissipation 
of CuCrZr to the ITER cooling water. This property can be jeopardised if the material would 
fail during its operational lifetime in ITER. 

The irradiation will be performed with the Hungarian Institute AEKI, who will take account 
of  the  low  level  dose  irradiation  (0.01  dpa).  All  post-irradiation  experiments  will  be 
performed at the NRG Hot Cells. The project will run from January 2011 to September 2013.  

In 2011, the irradiation design of the two capsules to be irradiated in the HFR was completed, 
including  the  preparation  of  the  safety  analysis  report  for  licensing  purposes.  The  capsule 
consists  of  an  assembly  of  tensile  and  Charpy  specimens  and  will  be  filled  with  sodium  to 
increase  the  heat  transfer  during  irradiation.  The  capsules,  named  CORONIS  01  and 
CORONIS  2  will  be  irradiated  in  positions  H2  and  G3  in  the  HFR  for  1  and  3  cycles 
respectively. The start of irradiation is planned for cycle 12-06. 

8. 

ISOTOPE PRODUCTION 

After  three  disrupted  operational  years  for  isotope  production  in  the  HFR,  2011  was  a  year 
with  a  normal  operational  pattern  as  experienced  in  the  years  before  2008.  Once  again,  the 
HFR was able to demonstrate that it plays an essential role as the largest producer of medical 
isotopes in Europe and one of the largest producers in the world. The total volume and value 
of the isotopes and associated services supplied from the HFR grew again in 2011. 

New  interesting  product  development  ideas  progressed,  both  in  conventional  application 
areas,  as  well  as  some  ground  breaking  areas  of  medical  technology.  Existing  development 
projects also progressed well. 

The production of Neutron Transmutation Doped (NTD) silicon for the specialist electronics 
industry was resumed after the final repair of the HFR in September 2010. During 2011, NRG 
returned to using a standard configuration of the HFR production facilities and reintroduced 
the  irradiation  of  silicon  ingots  to  produce  high  quality  products  used  in  high  voltage  and 
other specialist electronic applications that can only be served with NTD silicon. 

In  2011  NRG  continued  to  work  closely  with  other  players  in  the  Medical  Isotope  supply 
network, as well as with the Medical Community, Governments, the European Commission, 
AIPES,  the  OECD/NEA  and  the  IAEA.  These  actions  were  to  continue  to  support  the 
coordinated  efforts  necessary  to  minimise  the  future  risks  to  security  of  supply  of  critical 
medical isotopes. 

The  European  Commission  fully  supports  the  recommendations  of  the  OECD/NEA  High 
Level  Group  on  the  security  of  supply  of  medical  isotopes  and  actively  participates  in  the 

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work of the European Observatory on the supply of medical radioisotopes. NRG is working 
together with other international stakeholders on important issues such as full-cost recovery, 
outage  reserved  capacity  provision,  future  infrastructure  investment  and  conversion  to  LEU 
targets  for  Mo-99  production.  Further  work  to  ensure  the  sustainable  supply  of  medical 
isotopes will be carried out in  these international forums to establish an  enduring long term 
solution. 

9. 

FINANCIAL CONTRIBUTIONS FOR THE EXECUTION OF THE PROGRAMME. 

In  2011,  the  following  financial  contributions  were  received  from  Member  States  for  the 
execution of the programme: 

• 

• 

• 

Belgium: 400,000 € 

France: 300,000 € 

The Netherlands: 8,223,000 € 

It  should  be  noted  that  these  contributions  cover  the  expenses  according  to  Annex  II  of 
Council Decision 2009/410/Euratom. These amounts have been calculated in order to balance 
the forecasted costs of the reactor for the period 2011 taking into account an expected level of 
commercial income. In no case does the Commission cover any operational deficit, including 
potential costs for maintenance or repair. 

From this amount the Commission received 800,000 € as provisions for the Decommissioning 
fund1. 

As  of  31  December  2011,  the  total  amount  originating  from  the  decommissioning  fund  is 
13,949,000 €  

Other  expenditures  incurred  by  the  JRC  and  paid  from  the  supplementary  research 
programme budget:  

• 

• 

• 

1 

Direct  Personnel  (e.g.  for  HFR  supplementary  research  program  Management): 
257,000 € 

Materials  :  Support  HFR  (e.g.  Legal  Advice):  84,000  €,  Utilities  (e.g.,  electricity, 
water, heating): 582,000 €, Spent Fuel Management: 1,652,000 €  

Incidental Expenditures 2,222,000€  

The yearly contribution to the decommissioning fund has passed from 400,000 €/year to 800,000 €/year 
since 2004 due to a re-evaluation of decommissioning costs. This amount is taken from both the regular 
budget of the supplementary research programme and by the gained interest on the bank account of the 
supplementary  research  programme  (the  amount  of  the  interest  over  2011  was    333K€  and  therefore, 
467K€ was added from the regular supplementary research programme budget of 2011). 

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Glossary and Acronyms 

BPL 

Bottom Plug Liner 

COVRA 

Dutch Central Organisation for Radioactive Waste 

dpa 

EU 

displacements per atom  

European Union 

Euratom 

European Atomic Energy Community  

FAIRFUELS 

Fabrication, Irradiation and Reprocessing of FUELS and target for transmutation 

FP 

HB 

HEU 

HFR 

IAEA 

Framework Programme 

Horizontal Beam Tube 

Highly Enriched Uranium 

High Flux Reactor 

International Atomic Energy Agency 

INSARR 

INtegrated Safety Assessment of Research Reactors 

ISI 

ITER 

JRC 

LEU 

In-Service Inspection 

International Thermonuclear Experimental Reactor 

Joint Research Centre  

Low Enriched Uranium 

MARIOS 

Minor Actinides in Sodium-cooled Fast Reactors 

NeT 

NRG 

EU Network on Neutron Techniques Standardization for Structural Integrity 

Nuclear Research and consultancy Group 

OECD/NEA 

Organization for Economic Cooperation and Development / Nuclear Energy Agency 

PSF 

Pool Side Facility (PSF)  

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