The Nuclear Decommissioning Authority

NDA Sites Monthly Performance Update

General Evaluation - Key Elements

• Programme Performance was in line with expectations at the end of July 2009.  
• Electricity generation for July and Year to Date 2009/10 was above target.

Year to Date Cost and Schedule Performance
At the end of July 2009, the programme delivered work for less than planned cost.  Measured against the year to date budget the programme of work at the end of July was in line with expectations.

Earned Value Performance Management.  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.

Electricity generation at the fleet of Magnox nuclear reactors operated by the NDA was above target for July and Year to Date 2009/10. 

Items of Interest

Programme Items of Interest - Key Elements

• At Sellafield Thorp has reached a significant milestone having sheared its 6,000th tonne of fuel.  
• At Sellafield the Encapsulated Product Store 3 (EPS3) project team have achieved a major civil construction milestone.  
• Dungeness A has successfully completed a pathfinder project to explore the potential of a new method of temporarily storing intermediate level waste on site.

At Sellafield, Thorp has reached a significant milestone having sheared its 6,000th tonne of fuel.  Thorp sheared its first fuel on 27 March 1994 and has since reprocessed fuel from customers from nine different countries including the UK, Germany, Japan, Italy, Switzerland, Sweden, Netherlands, Canada and Spain.  There remains a substantial quantity of fuel which Thorp must process to meet its commitments under our existing contracts. Ultimately, the total amount of fuel to be reprocessed in Thorp will be determined by the NDA's Oxide Fuel Strategies.

At Sellafield the Encapsulated Product Store 3 (EPS3) project team have achieved a major milestone, completing the first roof concrete pour more than five weeks ahead of schedule.   This is one of the two Performance Based Indicators (PBI) milestones on the project, the other being the completion of the vault crane integrated works testing due in February 2010.  The roof-pour, at the west end of the store, required concrete to be poured over both the vaults, with approximately 900 cubic metres of concrete being poured.   The work leading up to the pour involved the erection of false work tables from the floor to the underside of the roof, which is approximately 17 meters high. It also saw the fixing of approximately 170 tonnes of steel and a number of encast items for the vault vent inlets.  This takes the total volume of concrete poured on the project to over 22,000 cubic metres since March 2008 and equates, in concrete pour terms, to around 70% completion of civil construction.  EPS3, when completed, will provide additional storage for Intermediate Level Waste (ILW) arising from reprocessing activities and potentially for ILW arising from legacy ponds & silos clean up activities.

Dungeness A has successfully completed a pathfinder project to explore the potential of a new method of temporarily storing intermediate level waste on site.  During the 20-week project rigorous testing was carried out before three MiniStore containers were filled with active resin slurry, dewatered, sealed and put into storage.  Regulatory approval from the Nuclear Installations Inspectorate (NII) has been granted for a period of 13 years storage, and not final disposal in a national repository.  However, the project could provide valuable data to support a case for using up to 50 boxes for longer term storage, negating the need for a purpose-built ILW store on site and potentially saving hundreds of thousands of pounds, and possibly final disposal.  A MiniStore is made of ductile cast iron, weighs around 18 tonnes and holds up to about 2.85m3 of waste.  The containers have been used extensively in Europe for 20 years, where they are certified for final disposal.  Magnox South is currently working with the NDA's Radioactive Waste Management Directorate (RWMD) and the regulators, including the NII and Environment Agency, on future potential use of the boxes.

Safety and Environment Performance

Safety and Environment - Key Elements

• One INES event  
• Two RIDDOR event  
• Three environmental non compliances

Nuclear Safety

One event rated at Level 1 on the International Nuclear Event Scale (INES) has been reported as occurring at NDA sites during the month.  

The INES event occurred at Capenhurst and was a result of a small leak from a Hex cylinder.

Radiological Protection

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. Dose figures are reported by calendar year rather than financial year and the following two graphs show average individual doses and maximum individual doses respectively (ordered by employee dose) for dosimeters worn by workers in calendar year 2008 and processed to date. Average individual doses and maximum individual doses should be compared with (and are all well below) the legal annual limit of 20 mSv.

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

Industrial Health and Safety

Two events reportable under RIDDOR occurred in the month.  

At Sellafield a Lost Time Accident (LTA) occurred as a result of a slip/trip/fall which resulted in a minor, but reportable leg injury.  

At Springfields the failure of an airline respirator occurred and was classified as a Dangerous Occurrence.

RIDDOR stands for the reporting of injuries diseases and dangerous occurrences regulations 1995.  RIDDOR '95 requires the reporting of work-related accidents, diseases and dangerous occurrences. It applies to all work activities, but not to all incidents.

Environmental Protection

Three environmental non-compliances have been reported in this period.  

At Oldbury a non-compliance occurred due to a high pH in partial effluent discharge.  

At Sellafield two non compliances occurred due to a liquor leak to ground via stuck ball cock and failure to deliver a Green House Gas (GHG) report on time.  

An Environmental Non Compliance is a breach of a permit condition set by the Environment Agency or the Scottish Environmental Protection Agency that prevents or controls risk of pollution to the environment.  

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.