Olympic Park clean up on track ahead of ‘Big Build’ start

All of the ‘Big Five’ venue sites are clear ahead of the start of the ‘Big Build’ this summer and two-thirds of the whole site, over one million square metres in total, has been cleared.

Over the past century the Olympic Park area has been contaminated through heavy industrial use. The ODA has been evaluating the area for contamination through desk studies, soil samples, monitoring and digging deep boreholes. These tests have found a range of different contaminants which are now being treated, including:

• petrol, oil, tar;
• heavy metals such as arsenic and lead;
• a 10cm gauge dial face painted with radium-based luminous paint, alongside other very low-level readings in small isolated areas;
• four hectares (around ten football pitches) of soil contaminated with Japanese Knotweed, a highly invasive and tough to kill plant;

Treatment is well underway with 1.5 million tonnes of contaminated soil being cleaned for reuse creating the platform for venues and parklands. Five soil washing machines have been installed on the Olympic Park to wash, sieve and shake out this contamination.

Billions of naturally occurring microorganisms are also helping clean nearly 50,000 tonnes of contaminated soil by eating petrol and diesel in large ‘composts’ on site. Japanese Knotweed has either been treated with herbicide over a number of growing seasons or macerated into tiny pieces then buried on site encased in secure membrane root barriers so deep that it cannot re-grow.

Work is also ongoing sorting over 120,000 tonnes of materials from a one hundred year old tip on the Velodrome site so that it can either be reused on site or recycled off site.

ODA Chief Executive David Higgins said: 'Getting the Olympic Park site, much of it contaminated, ready for the start of construction is a major challenge and we are on track. We are cleaning up neglected and polluted land both for the Games and legacy but we are also using the latest technology to do it in a sustainable way, reusing materials wherever possible and taking the minimum amount to landfill.'

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Images of the Olympic Park clean up are available on the London 2012 image library

For further information please contact the Olympic Delivery Authority Press Office on +44 (0)203 2012 700.

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