Nearly two million tonnes of contaminated soil has been cleaned for reuse on the Olympic Park in the UK’s largest ever soil-washing operation.
The 2.5 sq km Olympic Park was heavily contaminated through decades of industrial use.
Five soil-washing machines have completed cleaning most of the one million cubic metres of soil contaminated with oil, petrol, tar, cyanide, arsenic and lead.
Over 80% of contaminated soil has been cleaned for reuse on the Olympic Park using soil-washing, bioremediation beds (large-scale composting) and sorting machines, and over 98% of demolition materials on site have been recycled.
ODA chief executive David Higgins said: “With the soil washing complete the focus now moves on to the "green build" and ensuring sustainability remains at the heart of our work to deliver the venues and parklands for the Games and legacy.”
Key features of the Olympic Park clean-up:
- Nearly 3000 site investigations carried out to investigate contamination on site since October 2006
- More than 220 buildings demolished with 98% of the materials by weight recycled
- Over two million cubic metres of earth moved to form the platform for the Olympic Park ‘big build’
- Over 80% of one million cubic metres of contaminated soil cleaned and reused on site using innovative techniques including soil washing and bioremediation (large scale composting)
- Over 20m gallons of contaminated groundwater which existed on the Olympic Park treated using innovative techniques including treatment to remove oil and ammonia, injecting compounds into the ground which generate oxygen which in turn breaks down harmful chemicals, and controlling the movement of groundwater to prevent contamination entering local rivers.
- 10 football fields cleared of invasive Japanese Knotweed.
- Eight steel-framed buildings reclaimed for business reuse.
- Over 5km of riverbanks replaced or refurbished and 30,000 tonnes of silt, gravel and other materials dredged from the rivers.
- 140 archaeology trenches uncovering the pre-historic, Roman and Victorian history of the Olympic Park.
- An ecologic action plan to protect habitats and wildlife including translocating 4,000 smooth newts, 100 toads, 300 common lizards and creating over one hectare of new wildlife habitat on Hackney Marshes.