Presentaci

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ARN Nuclear Regulatory Authority
Spent Fuel Management of NPPs in Argentina D.E.
Alvarez and H.M. Lee Gonzales
International Conference on Management of Spent
Fuel from Nuclear Power Reactors 31 May - 4 June
2010, Vienna Austria
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Spent Fuel Management of NPPs in Argentina
Uses and applications of nuclear energy have
begun in Argentina in 1950, the year that the
National Atomic Energy Commission (CNEA) has been
created
Wide variety of activities were performed in the
nuclear field
Management of spent fuel and radioactive waste
Applying the legal and regulatory provisions in
force
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Spent Fuel Management of NPPs in Argentina
- National Congress Act Nº 24804 (1997)
to regulate the Nuclear Activity
Nuclear Regulatory Authority ARN- (1997)

to regulate and supervise

the nuclear activity
- National Congress Act Nº 25018 (1998)


to determine the Radioactive Waste

Management Regime (Nat. Radioact.

Waste Management Prog. - CNEA -)
- Joint Convention on the Safety of Spent Fuel
Management and on the Safety of Radioactive Waste
Management (2001)
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Spent Fuel Management of NPPs in Argentina
Argentine Government
Nuclear Regulatory Authority (ARN)
Ministry of Federal Planning, Public Invest
Services
Secretary of Energy
Nucleoeléctrica Argentina S. A. (NA-SA)
National Atomic Energy Commission (CNEA)
NPPs
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Spent Fuel Management of NPPs in Argentina
Government of Argentina exercises state ownership
of special radioactive fission material contained
in spent fuels from any origin NPPs and
experimental, research and/or production reactors
According to the Strategic Plan, the decision to
reuse fissile material contained in spent fuel
will be adopted before 2030
Meanwhile, the spent fuel generated by the NPP in
Argentina is being stored in interim storages
(Primary Responsible NA-SA)
At decommissioning time, an appropriate transfer
of Responsible Entity will be needed and before
that a decommissioning license should be required
by CNEA
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Spent Fuel Management of NPPs in Argentina
EMBALSE NPP
PHWR - 648 MW 700 km from Buenos Aires
BUENOS AIRES
ATUCHA I NPP
PHWR - 357 MW 112 km from Buenos Aires
ATUCHA II NPP under construction
PHWR - 692 MW 112 km from Buenos Aires
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Spent Fuel Management of NPPs in Argentina
Atucha I NPP
CNA I is a PHWR (357 MWe) of German origin which
is in operation since 1974
Former times natural uranium fuel
(0.71) Between 1995 and 2000 fresh fuel
gradually modified from natural to slightly
enriched uranium (0.85 nominal)
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Spent Fuel Management of NPPs in Argentina
Burnup MWd / tU Refueling
Natural uranium 6.000 1.29/day
SEU (0.85) 11.300 0.72/day
Fuel element composed by 36 bars ( 1), active
length of 5323 mm. Each bar contains 442 UO2
pellets cladding in a zircaloy-4 alloy tube with
an external diameter of 13.82 mm and 0.5 mm
thick. Fuel assembly (153.5 Kg of U) is very
slender, total length of 6028.5 mm, external
diameter of 107.8 mm and a weight of approx. 200
kg. Total number of fuel elements in the reactor
core is 252
Atucha I NPP
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Spent Fuel Management of NPPs in Argentina
Spent fuel is stored temporarily under water
hanging vertically in stainless steel racks
Atucha I NPP
two Pool Buildings
maneuvering pool four decay pools
maneuvering pool two decay pools
initial capacity 6944 FE positions compact
arrangement storing capacity of 8304 FE
completed full 3240 FE
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Spent Fuel Management of NPPs in Argentina
Atucha I NPP
With a load factor of 85, the arrangement will
satisfy the storage demand up to 2015. But the
end of the design of life of the Plant would be
reached in 2017 it will be required to arrange a
minimum of 620 free positions inside of the spent
fuel facility

A decision about life extension or
decommissioning should be taken in the near
future
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Spent Fuel Management of NPPs in Argentina
Atucha I NPP

• Implementation of a dry storage seems to be the
  best solution to cover necessities to create
  additional capacity for
• Storing the spent fuel (extension of life) or
• To transfer all the spent fuel out of the NPP in
  the case of decommission

A simplified conceptual design of a dry storage
is under development underground vertical silos
placed in a new building annexed to one of the
Pool Buildings
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Spent Fuel Management of NPPs in Argentina
Atucha II NPP
CNA II is a PHWR similar to CNA I. Start
operation in 2011. Spent fuel will be storaged
under water untill a dry storage alternative will
be defined
Pool Building
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Spent Fuel Management of NPPs in Argentina
Embalse NPP
CNE reactor is a typical CANDU 6 (648 MWe) on
load PHWR that is in operation in Argentina since
1984
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Spent Fuel Management of NPPs in Argentina
Embalse NPP
Fuel bundles are composed by 37 bars of 495.3 mm
length. Each bar, containing 38 UO2 pellets
(natural uranium), is cladding in a zircaloy-4
alloy tube. Fuel assembly has an external
diameter of 102.74 mm and 22 Kg of UO2
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Spent Fuel Management of NPPs in Argentina
Embalse NPP
Calandria has 380 horizontal pressure tubes
/channels with a capacity of 4560 fuel bundles
(12 per channel)
Refueling frequency at full power is 15.2 fuel
bundles per day, maximum burn up 7800 MWd/tU
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Spent Fuel Management of NPPs in Argentina
Embalse NPP
Leaving the core, the spent fuel bundles are
transfered underwater to the reception bay
(capacity 4800 bundles). They are disposed
horizontally on trays of a double array of 12
bundles each one which are transfered to the
storage bay and stocked in piles (capacity for
45144 spent fuel bundles, it means 10 years at
maximum power)
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Spent Fuel Management of NPPs in Argentina
Embalse NPP
A dry storage alternative was implemented in 1993
to cope with the spent fuel storage demand up to
the end of the operative life of CNE. Spent fuel
bundles remain at least 6 years in the wet
storage for thermal cooling and radioactive decay
after being transfer to the dry storage concrete
canisters arranged in a yard at the power
station site.
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Spent Fuel Management of NPPs in Argentina
Embalse NPP
Each full loaded canister contains 9 steel sealed
piled baskets, each one with 60
bundles Canisters are 6.3 m high vertical
cylinders and approx. 3 m external diameter.
Cooled by natural convection, were designed to
support some accidental events as earthquakes,
floods, tornadoes and the risk of explosions No
especial activities of maintenance are necessary
when the canisters are filled and sealed. At
present, there are 152 full loaded silos from
216
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Spent Fuel Management of NPPs in Argentina
Embalse NPP
Canisters yard is inside a double fence which
surrounded the NPP for security protection
CNE was designed with a 30 years nominal life
(load factor of 80). Due load factor 88 in
the last 10 years, the plant design life will be
reached in 2011. Life extension project is under
development
The modular design of the dry storage allows to
be enlarged, with no fulfillment of special
requirements
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Spent Fuel Management of NPPs in Argentina
Conclusions
A decision about the fuel cycle back-end strategy
will be taken before 2030. It is important to
mention that, recently, the National Supreme
Court has been issued on a cause related with a
possible entry to the Country of the spent fuel
from an Australian reactor constructed by an
Argentine enterprise, based on the fact that
spent fuel is not radioactive waste Meanwhile,
the spent fuel in each Nuclear Plant is
temporarily storage on site. In Atucha I, the
spent fuel is being storage in pools but a dry
storage design is under development. Embalse
counts with a dry storage since 1993 the spent
fuel, after certain period of time kept in wet
storage, is transferred to dry storage silos.
Enlargement of the spent fuel interim storage
capacity at CNE is made easily through the
construction of new modules of dry storage silos
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Spent Fuel Management of NPPs in Argentina
Conclusions (cont.)
The management of the spent fuel, during the
operation life of the Nuclear Power Plants, is a
responsibility of the operator (NA-SA) and at the
time of decommissioning the responsibility will
be of the Responsible Organization (CNEA). A
reasonable time before that moment both Entities
must come to make the appropriate transfer
agreements as well as CNEA should start the
decommissioning license procedure
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Spent Fuel Management of NPPs in Argentina
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