Back End Spent Nuclear Fuel Management in Germany · PDF file · 2014-07-17Back End – Spent Nuclear Fuel Management in Germany S. Geupel, ... Transportation of spent fuel from power

Back End – Spent Nuclear Fuel

Management in Germany

S. Geupel, K. Hummelsheim, W. Mester

Gesellschaft für Anlagen- und Reaktorsicherheit (GRS) mbH,

Germany

IAEA TM on Lessons Learned in Spent Fuel Management,

Vienna, 8 – 10 July 2014

German policy for spent fuel management

Concept and current status of spent fuel storage in Germany

Recycling of Plutonium and Uranium from reprocessing

Interdependencies with the disposal concept

2

Outline of the presentation

IAEA TM on Lessons Learned in Spent Fuel Management, Vienna, 8-10 July 2014

Dry storage before direct disposal in deep geological formations

Two centralised facilities for dry storage commissioned in the 1980s

(Gorleben, Ahaus)

Transportation of spent fuel from power reactors to foreign reprocessing

plants (La Hague, Sellafield) is prohibited since July 2005 (revision of

the Atomic Energy Act in 2002)

On-site dry storage facilities built at all NPP sites with existing spent fuel

inventories (except Obrigheim) since 2002

3

The German policy for spent fuel management


Dry spent fuel storage facilities in Germany

4

12 On-site storage facilities

in operation

(since 2002 – 2007)

1 On-site storage facility

applied for (2005)

3 Central storage facilities

in operation

(since 1992, 1995, 1999)

1 Local storage facility

at research center

in operation (since 1993)

License

expires

after

40 years

License

expired

since

July 2013

IAEA TM on Lessons Learned in Spent Fuel Management, Vienna, 8-10 July 2014 4

5

German concept for dry storage

Accident-safe dual purpose metal casks for storage

and transport with

two independent sealed barrier lids

permanent monitoring for leak-tightness

vacuum dried and helium filled cask interior

type B(U) certification

Casks emplaced in a storage building for additional

radiation shielding and weather protection


Operating licenses for centralised and on-site storage facilities are

generally limited to a period of 40 years, starting with the

emplacement of the first cask

Limitation relies on administrative reasons (anticipated startup of

a disposal facility for spent fuel and heat-generating waste), not on

the technical lifetime of the casks or the storage building

Pending site selection process for a disposal facility increases the

probability that an extension of the licensed storage period beyond

40 years will be needed

Stored casks have to be transportable at any time during storage

Design approval certificates for transport of casks are valid only for

periods of 3, 5 or 10 years

Aspects of licensing

6 IAEA TM on Lessons Learned in Spent Fuel Management, Vienna, 8-10 July 2014

16 Licenses for dry spent fuel storage facilities

1000 transport and storage casks with B(U) type approval emplaced

~ 650 to 700 casks for spent fuel are additionally needed

16 different cask types approved for spent fuel from power reactors,

research reactors and vitrified HAW from reprocessing

Cumulated amount of spent fuel generated until decommissioning of

all German NPPs (end of 2022): approximately 17,200 t HM, of which

Current status of spent fuel storage in Germany

7

~ 10,500 t HM are to be disposed of in a repository

~ 6,250 t HM were reprocessed, producing ~ 1,900 t heat-generating

waste to be disposed of in a repository

~ 350 t HM were disposed of via other pathways


8

8 NPPs were permanently shut down in 2011, awaiting

decommissioning and dismantling

Irradiated fuel has to be unloaded from the core and stored

Demand of 190 casks shortly for shutdown NPPs

Loading of 40 casks per year

Maximum enrichment of UO2 fuel between 4.0 and 4.7 % U-235

Several fuel elements irradiated only 11 to 300 full load days

Cask approval for special cases

Consequences in Germany from Fukushima accident

Some cask licenses require a minimum of burnup to ensure sub-criticality

Damaged fuel is not allowed in casks (due to corrosion, H2 generation)


German spent fuel for reprocessing

shipped to

9

37 t Pu-fiss

286 casks HAW + MAW

Urep

Spent fuel shipped for

reprocessing until 2005


Recycling of Plutonium as Mixed Oxide (MOX) fuel

10

Plutonium recycling as MOX carried out since 1966

Licensed in 12 German NPPs (light water reactors), actually used

in 5 operating NPPs

In the past also applied in German prototype reactors

Burning ~ 28% of Plutonium by use of MOX fuel

All Plutonium from reprocessing will be recycled until 2016,

currently 96% reached

Approximately 37 t fissile Plutonium in 2700 MOX fuel elements

recycled

Limited number of positions in dual purpose casks for spent MOX

fuel elements available

Cask approval with more MOX positions

Recycling of Plutonium as Mixed Oxide (MOX) fuel


11

Beside Plutonium, also Uranium is partly recycled

ERU fuel is used in 3 operating NPP (1800 fuel elements)

Enrichment up to 4.6% U-235

Burnup up to 60 GWd / tHM

No distinction is made between UO2 and ERU for spent fuel storage

in casks

Recycling of Enriched Reprocessed Uranium (ERU)


12

Stress test for German spent fuel storage facilities

after Fukushima accident (1)

The German Nuclear Waste Management Commission (ESK) was

asked by advisory request by the Federal Ministry of Environment,

Nature Conservation and Nuclear Safety (BMU) to carry out a stress

test for all 4 centralised and 12 on-site storage facilities for spent fuel

The stress test should assess the robustness of spent fuel storage

facilities regarding beyond design basis accidents

Security measures are not addressed by the stress test

Assessment of the stress test was performed by the ESK with

technical support by external experts


13

Load cases that have been assessed:

Results of the stress test were published by the ESK in March 2013

http://www.entsorgungskommission.de/englisch/downloads/eskstress

testteil114032013revenhp.pdf


1 Earthquakes

2 Flooding

3 Heavy rain

4 Other weather-related events

5 Loss of electrical power

6 Internal fires

7 External fires

8 Aircraft crashes

9 Blast waves

Stress test for German spent fuel storage facilities

after Fukushima accident (2)

http://www.entsorgungskommission.de/englisch/downloads/eskstresstestteil114032013revenhp.pdf

http://www.entsorgungskommission.de/englisch/downloads/eskstresstestteil114032013revenhp.pdf

14

The analyses and assessments carried out by the ESK have shown

that the storage facilities for spent fuel and heat-generating waste

comply with the highest stress levels and reach the highest degree

of protection for almost all load cases

The design of the transport and storage casks ensures compliance

with the general protection goals during storage and also ensures

that even in case of beyond design basis accidents, no major

disaster control measures are required

For none of the facilities considered in the stress test, a failure of

components or measures due to the postulated beyond design load

cases that may lead to a sudden rise of the radiological effects

outside the facility is to be feared

No deficiencies in the design requirements of the facilities have

become apparent in the stress test

Results of the stress test


15

Milestones from storage to disposal

Exploration of Gorleben salt dome suspended

Preliminary safety analysis of the Gorleben site finished

Approval of the Site Selection Act by the German Parliament

Commission ‘Disposal of high active waste’ will prepare basic

principles for decision making with regard to

safety requirements, methodology for safety assessment

general and host-rock specific selection and exclusion criteria

participation of the public

Aboveground exploration of up to 5 sites

Underground exploration of up to 2 sites

Final decision for a repository site

Licensing procedure for the construction, operation and closure

of the repository

Commissioning of the repository

End of 2012

March 2013

July 2013

Mid of 2014 –

Mid of 2016

2016 – 2023

2024 – 2031

End of 2031

2032 – ???

???


16

Site Selection Act for a repository for spent fuel

and heat-generating radioactive waste

Main objective: Selection of a disposal site until 2031

Key provisions:

New site selection procedure starting with a blank map of Germany without

any site proposals

Site selection based on scientific criteria and the highest safety standards

No premature decisions by excluding individual sites

Fundamental decisions to be taken by the German Parliament

Transparency and public participation in all phases of the stepwise

procedure in order to reach a decision based on broad consensus

Projected costs until finishing the site selection procedure:

ca. 2 Billion Euros (to be paid by the waste producers)


Key issues being relevant for

the site selection process will be

evaluated by the Commission

‘Disposal of high active waste’

Drift emplacement

of spent fuel in

thick-walled casks

(POLLUX or CASTOR)

Borehole emplacement

of spent fuel in canisters

(BSK 3)


German disposal concepts for spent fuel

pursued as reference and alternative concepts for the disposal of spent fuel in a salt formation

until commencement of the Site Selection Act in 2013

17

18

German container concepts for spent fuel disposal

POLLUX

self-shielding, thick-walled

POLLUX cask

Reference Concept Alternative Concepts

On-site storage in

Conditioning after

intermediate storage

Reloading

Transfer to disposal

Emplacement in

Current status

non-shielding

BSK 3 canister

CASTOR V/19 casks (PWR fuel)

CASTOR V/52 casks (BWR fuel)

BSK 3

Drift Borehole

Transfer cask

Disassembling of

spent fuel assemblies

Aboveground testing finished in

2000, basis for repository layout

Aboveground testing

finished in 2009

DIREGT

Borehole

CASTOR V/19

CASTOR V/52

Whole spent fuel

assemblies

Feasibility studies

ongoing


TM on Lessons Learned in Spent Fuel Management, IAEA 8-10 July 2014 19

Potentially suitable host rock formations

for a geologic repository in Germany

Exploration mine Gorleben

20

Thank you for your interest !

Any questions ?

NPP Brokdorf NPP Grohnde


Documents

Back End Spent Nuclear Fuel Management in Germany · PDF file · 2014-07-17Back End – Spent Nuclear Fuel Management in Germany S. Geupel, ... Transportation of spent fuel from power