As part of its monitoring strategy, HSE is committed to carrying out a number of audits. The first was carried out in Transco's West Midlands Region in December 2002. It focused on verifying that the 2002/03 plan for iron mains abandonment was being met in relation to a) Transco's policy replacement and b) the replacement of Medium Pressure Ductile Iron (MPDI) mains.
The audit found a well-established organisational structure in place to manage the mains replacement process. It also provided reassurance about the accuracy, quality and reliability of the mains replacement performance data presented to HSE on a quarterly basis. Transco implemented a detailed action plan in response to the auditors' recommendations.
Over the period January 2002 to March 2003, Transco planned to replace 2575 km of iron mains. In the event they achieved 2846 km, some 271km over budget. This figure includes a substantial amount of Medium Pressure Ductile Iron (MPDI) mains, necessary to meet the terms of an Improvement Notice served on Transco in September 2000. This required Transco to replace all their MPDI mains within 30 metres of buildings by 31st December 2002.
In this period, Transco abandoned 1411 km of MPDI mains, 335 km more than forecast. These additional lengths of MPDI were discovered during the course of the planned work. A small amount came to light late in 2002 and could not be abandoned before the expiry date of the Notice. The Notice was extended to 30th April 2003 to allow planned removal. This was achieved and the Notice discharged.
Transco achieved their mains replacement targets for the period January 2002 - March 2003. The removal of more than 2800km of MPDI mains in response to the Improvement Notice is not only a significant achievement, but has also removed a substantial risk from the network.
HSE's audit of Transco's mains replacement activity in the West Midlands region found that Transco had sophisticated systems for planning and managing mains replacement activity, together with sufficient trained and competent staff to deliver the programme. The audit confirmed the accuracy and reliability of data submitted by Transco to HSE.
HSE followed-up Transco's action plan for implementing the report's recommendations and are satisfied that these were fully implemented.