Technical Committee on Environet J.L.Goswami-BARC-India

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Technical Committee on Environet
J.L.Goswami-BARC-India

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Indian nuclear power programme

• For sustainable energy security, recycling of
  fissile /fertile element in spent fuel and
  capitalisation (utilisation) of vast thorium
  reserves is must
• Three stage strategy involving closed fuel cycle
• Ist stage utilisation of nat.uranium in PHWRs
  and production of Pu
• 2nd stage use of Pu in fast breeder reactors and
  utilisation of thorium
• 3rd stage utilisation of U-233 and Pu in AHWRs

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Indian Nuclear Power Programme
15 PHWRs 2 BWRs (4120 MWe) FBTR (40 MWth) KAMINI (30 kWth)
Under Construction 3 PHWRs 2 LWRs (2660 MWe) Under Construction PFBR (500 MWe) Under Planing AHWR (300 MWe)
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Indian perspective on Decommissioning and
Environmental Remediation

• Indian nuclear facilities have not yet reached
  the stage of final retirement
• The emphasis is on ageing management and life
  extension of facility by refurbishing,
  modifications and equipment replacements.
• These practices have been successfully deployed
  for Research Reactors , NPPs and Radiochemical
  plants
• Research Reactor CIRCUS
• Tarapur Atomic Power Station
• Reprocessing Plant Kalpakkam
• Presently following facilities are under
  planning for decommissioning
• Waste Immobilisation Plant Tarapur
• Advance Vitrification Facility Tarapur
• Some nuclear facilities have also been
  decommissioned for putting up advanced plants-
• Thoria reprocessing plant at Trombay
• Research Reactor Zerlina
• Research reactor Purnima

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Refurbishing of Research Reactor CIRUS

• Refurbishing undertaken during 1997-2002 after 30
  years of operation
• Assessment review was carried out during1992-97
  for structures, systems and components in
  respect of seismic requirement , stored energy in
  graphite reflectors ,safety analysis etc
• Total cost of refurbishing was 10 of a new
  replacement reactor and life extended for 20
  years
• Refurbishing Plan and Preparatory Work included
  Development of Procedures Special Tools and
  Regulatory Review

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Refurbishing of Research Reactor CIRUS

• Remote repairs for in-accessible areas
• Cover gas pipe flange joints replacement
• Leak rectification of aluminium thermal shield
  coolant pipe
• Primary coolant pipes replacement
• Ball tank leak repairs
• Extensive external corrosion protection measures
• Remote tools like remote sealing clamp tool ,
  gouging tool and tightening tool were developed
  and mock trials taken

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Partial Decommissioning of Fuel Reprocessing
Plant at Kalpakkam

• The plant remained shut down since Aug 2004 for
  revamping and modifications.
• Modifications have been carried out to improve
  plant performance and to address safety related
  issues encountered during previous campaigns.
• The radiation fields inside hot cells were around
  1-5 R/hr .The total man-Rem consumed was 760 Rem
• Total Solid waste generated Cat-I 2400 m3,
  Cat-II 17 m3, Cat-III 10 m3 , Cat-IV 12 m3

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Decommissioning of Fuel Reprocessing Plant
Trombay

• Partial decommissioning was taken up in 1974 to
  increase the capacity and life of the plant.
• Removal /emptying of recoverable nuclear material
  from the system/waste streams
• Detailed radiation survey of areas/equipment and
  piping
• Indirect decontamination of process equipment and
  piping using chemicals such as nitric acid, sod
  hydroxide etc to remove bulk of radioactivity
• Further decontamination to external surfaces by
  water jet and subsequent radiation mapping
• Dismantling of equipment and piping employing
  remote gadgets and for difficult positions
  manually by contact dismantling
• Installing the new equipment and piping
• Segregation of radioactive solid waste
• Management of the liquid waste
• The experience gained was valuable in identifying
  the design improvements such as Plant layout for
  removal of components, provisions for radiation
  survey preparedness in waste handling

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Decommissioning of Reprocessing Plant, Trombay

• Six out of the eight process cells were
  decontaminated, decommissioned, and
  reconditioned, reducing the radiation level to
  the minimum possible extent and also made all the
  surfaces of the process cells free of
  contamination to facilitate the erection of
  equipment and piping for the new plant, without
  undue exposure to the plant personnel.

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Decommissioning of a Thorium Processing Facility
at Trombay

• Plant started in 1955 to process natural thorium
  and due to ageing and excessive corrosion was
  decommissioned in 2000
• Initial Radiation field around 5-300 mR/hr
• The steps undertaken were decontamination and
  removal of tanks equipments from the plant with
  subsequent dismantling of civil structures
• Segregation and disposal of radioactive waste .
• Radioactive solid waste quantity of 2150 m3
  consisting mainly of 70 concrete and 30 as
  metallic waste was disposed in NSDF

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Tank Remediation by Ion Exchange

• A trailer mounted mobile IX unit for treatment
  of alkaline ILW consisting of
• Shielded IX Columns
• Piping and instrumentation
• Shielded enclosure
• Ventilation for enclosure
• Radiation monitoring
• Remotisation

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Decommissioning Robot Remote forklift
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Research and development efforts on Environmental
Remediation

• Analytical techniques for measurement
  (monitoring) of residual activity
• Treatment schemes for tailings from uranium
  extraction (mining/milling)
• Modelling studies on activity migration and
  treatment schemes /processes for soil
  decontamination

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Challenges ahead

• Development of remote cutting devices for steel
  plates, pipes, concrete etc
• Development of underwater tools for
  decontamination and dismantling
• In the wake of changed policy involving
  multinational participation some facilities may
  be decommissioned to the green field stage
  including environmental remediation
• Management and disposal of Radioactive Waste and
  final repository site selection and construction

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Thank You