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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
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Calder Hall Sellafield
Decommissioning
Martin AdamHeriot-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