Over 800,000 cubic metres of soil contaminated with substances such as oil, petrol, tar, arsenic and lead, is being cleaned so it can be reused to create the Olympic Park and land for future development.

Sixty scientists, technicians and other specialist staff based in a laboratory on site are utilising state-of-the-art equipment which runs around the clock testing soil to see if it needs to be cleaned and if decontaminated soil is ready to be reused on site. The scientists are also monitoring ground and surface water and air across the site to check for contamination and track the clean up progress on a weekly basis.

ODA Director of Infrastructure and Utilities Simon Wright said: 'The clean up of the Olympic Park is one of the most challenging ever undertaken in the UK. With this laboratory on site we are able to use cutting edge technology to quickly tell when soil needs to be cleaned and when it’s clean enough for reuse on site. This rapid process is helping us prepare former industrial land for the construction of world class venues and a brand new urban park. The team of scientists are also helping us ensure the safety of local people and the site workforce and protect the environment as we transform a neglected corner of east London.'

Almost the entire Olympic Park site (95 per cent) has now been investigated. Two large remediation facilities have been created on the Olympic Park with four soil washing machines installed to wash, sieve and shake out contamination.

To support the clean up a full-scale soil analysis laboratory has been set up site. The team of 60 scientists, technicians, engineers and data management staff are using state of the art analytical equipment to test up to 80 samples of soil a day to ensure it is ready for reuse on site.

An off-site laboratory is also being utilised to monitor water and air samples from across the site. To date approximately 1,000 surface and ground water and 5,400 atmospheric samples have been taken. The laboratory is also guiding exactly how soil can be reused on site, such as how much weight it can hold.

Notes to editors:

Soil washing will be used to treat most of the estimated 800,000 cubic metres of contaminated soil. Machines add water to soil and separate it from contamination by either shaking or leaving it to settle and filtering out clean sand or gravel that is safe to reuse. In some instances chemicals are added to the water to tackle particular types of contamination. The water is reused after being treated. A small amount of concentrated waste from the process is squeezed to reduce its water content and it is then taken to a licensed landfill.

In some instances other treatment methods may be used. If soil contains just petrol related substances (petroleum hydrocarbons) and no other contamination it may be treated by bioremediation. This involves storing the soil in large concrete containers and adding oxygen to help breakdown the contamination naturally, a process similar to composting. Some kinds of contamination will be contained where it is, using a process of chemical stabilization to trap contaminants under the ground and prevent them leaking into the ground water system.

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

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