We manage an inherited portfolio of historically contaminated land including former manufactured gas plants, industrial landfills, former and current gas holders and electricity substations on our transmission and distribution networks. Sites can sometimes have a complex mix of contamination dating back over 100 years.

National Grid manages land contamination issues on 678 sites, the majority of which were previously used for gas production. In the US, this includes obligations in relation to land owned by third parties.

During 2008/09, environmental work stages were completed on 316 sites of which 22 included remediation. As a proportion of the programme in the UK is linked to the redevelopment of brownfield sites, the economic downturn has adversely influenced the number of remediation work stages completed.