Sellafield Nuclear Power plant

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					Calder Hall
 Sellafield
Decommissioning

             Martin Adam
     Heriot-Watt Edinburgh
                      2008
History
 Located in Cumbria, England
 Worlds First Commercial Nuclear Power
  Station
 Construction started 1953, completed
  1956
 Her Majesty the Queen Opened the
  Power Station on 17 October 1956
 Generated Power Until March 2003
 Consisted of 4 Magnox reactors each
  capable of 50 Mwe of power each.
 Produced over 70TWh of electricity in its
  operational life.
 History

 Its early life primary function was to
  produce weapons grade plutonium

 From 1964 it was mainly used for
  commercial fuels

 Although it was not until 1995 when the
  UK government announced that all
  production of plutonium for weapons
  had ceased
Calder Hall Site Mission:

 Safely, securely and cost-effectively
  remove all fuel and buildings from site

 To processes, treat and dispose of all
  waste arise

 To remediate the ground, where
  necessary and make the land available
  for reuse.
Current plan

 Stage 1: Defuelling & Preparations 2003 – 2008

 Stage 2: Intermin Decommissioning 2004 – 2011

 Stage 3: Care & Maintenance 2011 – 2105

 Stage 4: Final Site Clearance 2105 - 2117
Defuelling & Preparations: 2003 - 2008

 Remove all spent fuel and transfer it to Sellafeild Fuel Handling
  Plant
 Arrangements must be taken to improve nuclear safety before
  defuelling can commence
 Removal of all fuel elements from the reactor core
 Despatch of all spent fuel from the station
 Calder Hall has four reactors, with each reactor holding 1696 fuel
  channels holding either five or six fuel elements
 Therefore the site had approx 40,000 elements to remove
 This phase also deals with maintenance issues dealing with both the
  defuelling process and the ongoing site management.
Intermin Decommissioning: 2004 - 2011
 Will begin in parallel with the defuelling process.
 Reactor 1 and Turbine Hall A, are currently under
  a request to become listed buildings.
 Conservation of remaining 3 reactors into
  safehouses to be used during the care &
  maintenance phase
 Hazard reduction activities; Asbestos removal from
  heat exchangers and from within the turbine halls
 Removal of redundant facilities (cooling systems,
  utilities, generators ext.)
 Cooling towers were demolished on 29th of
  September 2007
 All Plant not required for industrial Heritage
  purpose or C&M removed.
 Reactors 2, 3 & 4 heat exchangers dismantled and
  removed.
Intermin Decommissioning: 2004 - 2011
 Intermediate waste arising will be transported
  to the low level waste repository in sellafield
 New construction activities are required
 Three reactors will require weather proofing
  and conversion.
 This will involve re-cladding the roofs which
  will also have to been replaced/refurbished
  every 30 years during the care and
  maintenance phase
 Modification to existing facilities to maintain
  services such as water, telecommunication,
  fire detection and security system
 A new electrical ring main will be installed, to
  allow safe termination of existing services
 Before C&M can start all hazards must be
  immobilised in a safe and secure way
Care & Maintenance: 2011 - 2105
 This stage is designed to ensure that minimal human intervention is
  needed during the 100-year Care and Maintenance Program
 Initial phase will last 5 years where the site will remain staffed
 After this phase, surveillance, safety and security will be of great
  importance
 Safehouses will be routinely maintained, inspected regularly and will
  undergo periodic surveys.
 The Scope will also include inspections following severe weather
  conditions to check for any failure of the watertight envelope.
 Weekly external inspections (e.g. identification of any damage)
 Monthly ground maintenance on the site
 Half-yearly external engineering inspections for minor maintenance
  issues
 Annual internal engineering inspections for minor maintenance issues
 External/Internal inspections at 25 year intervals for major maintenance
  issues
Final Site Clearance: 2105 -2117
 To facilitate this stage a suitable site
  infrastructure will be installed
 A waste management facility (WMF) will be
  constructed to process the waste arising
  during this phase
 Wastes will be transferred in a controlled
  manned to the WMF, monitored and
  sentenced
     Active waste will be packed in a waste
       disposal boxes, transported off site and
       disposed off
     Clean waste will be used of infilling voids
       or disposed of off site
 Reactor 1 and Turbine Hall A are assumed to
  no longer be listed buildings, therefore will be
  removed
Final Site Clearance: 2105 -2117
 Entry to safehouse will be gained during
  early phases of clearance to carry out
  preliminary structural and radiological
  surveys
 In turn a section of each safehouse roof will
  be removed to allow large items of the plant
  to be lifted out
 Once all active plant and any contamination
  have been removed from the safehouses
  they will be demolished and any voids
  below GWL backfilled
 Near the end of the phase all services,
  structures installed to support the project
  will be deplanted, demolished and
  removed.
Cost:



 Total overall estimated
  cost around 1 Billion
  GBP




                            Cost Distribution by
                              Key Phase (£k)
Thank You For
Your Attention

				
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posted:1/21/2012
language:English
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