The Nuclear Decommissioning Authority

NDA Sites Monthly Performance Update

General Evaluation - Key Elements

• The programme delivers work in-line with budgeted costs.
• The overall NDA programme is behind schedule.
• Under Portfolio Management the first efficiency performance reviews have taken place.
• Year to date electricity generation remains above target.

For financial year 2007/8 with the exception of Sellafield plans are not over pressured. Work is ongoing to assess the funding requirements for Sellafield. Under Portfolio Management the first efficiency performance reviews have taken place. Cashable efficiency savings will be released to Portfolio Management and non-cashable efficiency savings will be retained for acceleration. Financial year 2007/8 efficiency targets have been set and the monitoring programme has started. Year to Date Cost and Schedule Performance At the end of July 2007, the programme delivered work in-line with expected costs. Measured against the year to date budget the programme of work at July is behind schedule.

Year to Date Cost and Schedule Performance
At the end of July 2007, the programme delivered work in-line with expected costs. Measured against the year to date budget the programme of work at July is behind schedule.

Please note: We use Earned Value Performance Management to measure programme performance. This compares the budgeted cost of work that was scheduled with the budgeted cost of work that was actually performed to determine schedule performance and the budgeted cost  of work actually performed with its actual cost to determine cost performance.

Year to date Electricity generation at the fleet of Magnox nuclear reactors operated by the NDA was above target at the end of July 2007. Electricity generation for the month was marginally below target.

Items of Interest

Key Elements

• THORP restarts shearing after 2 years 3 months following the Feed Clarification Cell (FCC) event.
• Progress has been made in a number of areas at the Sellafield MOX Plant (SMP).
• At the Low Level Waste (LLW) Repository SLC Limited the last bulk drummed Plutonium Contaminated Material (PCM) was returned to Sellafield during the period.
• The LLW Repository Ltd formally came into being at midnight on 28 July 2007.
• Hunterston A has been given approval to make the necessary modifications to the Skip Transporter in the Cartridge Cooling Pond.
• The leaking fuel element at Sizewell A has been shipped to Sellafield.
• The Dounreay Material Test Reactor (DMTR) pond at Dounreay has been drained. Man entries are due to start in August.
• Thorium Nitrate drums have been successfully returned to Dounreay from Peru.
• Achievements have been made on Piles Projects at Windscale.
• Schedule slippage has been seen on the Effluent Pipeline Project at Chapelcross.
• The Magnox Dissolution Plant has been shutdown at Dungeness A.
• Sizewell A has suffered the effects of localised freak weather.
• Work continues on the Dounreay Cementation Plant (DCP) recovery programme.

• The first pellet lot following clean down has been successfully processed within the pelleting areas which signifies the start of the medium enrichment campaign.
• The qualification report for the Rod Works Order on Line 1 has been approved. This is a key stage in certifying the fuel prior to shipping.
• Alternative Residue Storage - Phase 1 store has been successfully works tested with operators. This represents progress toward mitigating a key plant operations risk.
• X-Ray Obsolescence - The key milestone of identifying replacement end weld and linear array detectors has been achieved and the results presented to Process Engineering & Quality Control with excellent feedback received. This is a key mitigator of Area 400 plant obsolescence risk.

At the Low Level Waste Repository the last bulk drummed Plutonium Contaminated Material (PCM) was returned to Sellafield on 20 July 2007. This was an enabler to site re-licensing.

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The LLW Repository Ltd formally came into being at midnight on 28 July 2007. The new company is a requirement for the competition programme. The new company was also re-licensed under Nuclear Site Licence 82. Simultaneously the Environment Agency (EA) transferred the Radioactive Substances Authorisation to the new company and the Department for Business, Environment and Regulatory Reform (DBERR) signed the Nuclear Transfer Scheme.

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Hunterston A has been given approval by the regulator to make the necessary modifications to the Skip Transporter in the Cartridge Cooling Pond. The site has now satisfied the regulators in all matters relating to the pond improvement plan. This is a critical step towards the recovery of the Skip Decommissioning Project.

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The leaking fuel element at Sizewell A, has been shipped to Sellafield. The despatch of this element, which has been “wet-bottled” in the pond since removal from Reactor 1 in October 2006, represents a major achievement for the site in terms of hazard reduction.

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The Dounreay Material Test Reactor (DMTR) pond has been drained and is ready for man entries to start in August. This will be the first pond at Dounreay to be decommissioned.

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The return of the Thorium Nitrate drums from Peru to Dounreay has been completed satisfactorily.

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Achievements have been made during the month on Windscale Piles Projects:-

• The first shipment of prototype removal equipment has been delivered. This means that the project is ahead of schedule to have the prototype available for demonstration as part of the Pile 1 50th anniversary activities.
• Pile 2 isotopes have been placed in Intermediate Level Waste (ILW) storage. This work has been successfully completed under budget. No isotopes now remain in the Pile 2 Reactor.

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Work continues on the Evaporator D project at Sellafield with progress being made on the bulk removal of the spoil. Blinding to the south of the site has been completed and construction of skin walls is progressing.

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A number of leaks into and out of the Effluent Pipeline at Chapelcross have been detected between Manholes 18 and 19. Cleaning works on the pipeline have been severely hampered and temporarily stopped to allow investigation and remedial action to allow the line to be returned to temporary service to allow discharge of built-up effluent from the site. Until the investigation is completed and a Best Practical Environmental/Engineering Option is concluded and recommendations implemented, work on the Effluent Pipeline cleaning will be stopped.

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At Dungeness A, filters on the Magnox Dissolution Plant were found to be clogged with sand. The facility was shutdown without incident. Nozzle failure with the sand filters is being investigated and repairs are expected to take 8 weeks.

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Sizewell A has suffered the effects of localised freak weather damage as a result of lightening strikes and torrential rainfall. The following areas have been affected:-

• Water ingress into new accommodation building;
• Temporary failure of security alarms and cameras;
• Some delay and clean up work required in project areas; and
• Active Effluent Discharge Refurbishment Project affected by a 4-week delay.

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Recovery work continued during the period on the Dounreay Cementation Plant (DCP) recovery programme with dismantling and decontamination of the W3 mobile shield plug successfully completed and the temporary shielded enclosure dismantled. New containment has been erected around the plug to facilitate modification.

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Safety and Environment Performance

Safety and Environment - Key Elements

• No INES level 1 or higher events reported.
• Three RIDDOR reportable events, all at Sellafield.
• Two environmental non compliances have been reported.
• Recycling achievements are noted at Chapelcross and Trawsfynydd.

Dosimetry is the measurement of absorbed dose in matter and tissue resulting from the exposure to ionizing radiations.

Nuclear Safety

No events rated at Level 1 or higher on the International Nuclear Event Scale (INES) have been reported at NDA sites during the period.

Oldbury successfully demonstrated their emergency arrangements to the regulator.

Dosimetry

The sites provide data on average individual dose, maximum individual dose and collective dose. These metrics are measured separately for SLC employees and for contractors. Note that the dose is measured by a dosimeter which has to be processed before the dose can be added to the record. Therefore dose figures always lag behind the current date. Dose figures are reported by calendar year rather than financial year and the graphs below present the latest figures for dosimeters worn by workers in calendar year 2007 to date. Individual average and maximum doses should be compared with the legal annual limit of 20 mSv.

Industrial Health and Safety

Five RIDDOR events were reported in the period:

Three RIDDOR Lost Time Accident (LTA) events were reported in the period:-

• At Sellafield, a scaffolder jarred his arm whilst tightening a fitting resulting in pulled ligaments.
• At Sellafield, a scaffold labourer banged his wrist and was diagnosed with strained tendons and ligaments.
• At Sellafield, an operator twisted his ankle when he trod on a vertical support girder fixing bolt head resulting in ligament damage.

In addition, a further RIDDOR Lost Time Accident (LTA) event has been reported which occurred in June:-

• At Sellafield, an individual experienced pain in his back whilst testing a master slave manipulator.

Environmental Protection

Two environmental non-compliances have been reported in this period:-

• At Trawsfynydd, sediment was washed into drains as a result of high rainfall. This caused the Diversion Culvert discharge consent limit for suspended solids to be exceeded.
• At Dounreay, failure of the Castle Gate Seep Pump resulted in the discharge of low level radioactivity from an unauthorised discharge point.

A warning letter from the Environment Agency was received by Berkeley as a result of the Active Effluent Treatment Plant overflow event in March 2007.

Safety and Environmental Achievements

Following the successful demolition of the cooling towers at Chapelcross, 270 tonnes of steel reinforcing bar has been extracted from the rubble and sent for recycling.

The Trawsfynydd site have calculated that out of a total of 2400 tonnes of waste produced in 2006/7 (excluding tankered sewerage), 90% was recycled.

Wylfa has achieved the Corporate Standard Health at Work Gold Award from the Welsh Assembly. This is awarded to organisations demonstrating a commitment to health and wellbeing in the workplace.

Please note
We give the actual number of occurrences in each category. Not all sites employ the same number of people and/or undertake the same activities. This must be taken into account before comparisons between sites can be made.