I work on the north of the Olympic Park and our team runs two soil washing machines. The machines are helping to clean up contaminated soil (mostly from the previous industrial use of the area) so that it can reused in the creation of the Park.
Across the site, soil has been tested for a range of contamination, which consists mostly of hydrocarbons such as petrol and oil. Samples of contaminated soil are tested in an on-site lab to measure the levels of contamination and to establish the appropriate treatment. The soil is then sent to our 'Soil Treatment Centre (STC)'.
Soil washing on the Olympic Park:
The soil washing process is ideal for cleaning and separating contaminated soil. Afterwards, washed sands and gravel are blended again to suit the area on which they are going to be reused.
The washing process works by stripping the contamination away from the larger particles (sands and gravels) and concentrating it in the finer silts and clays. These then undergo further testing and treatment to minimise the amount of material that has to be sent to landfill because it can’t be reused. The soil washing machine also uses powerful magnets to draw scrap metals out of the contaminated soil, which is often found in ground that has been 'made' from rubble or landfill.
A digger puts some soil into the soil washing machine:
As well as reusing gravel and sand, we are able to reuse any dirty water from the contaminated soil by washing it along with the soil in the soil washing machines.
We also use the machines to clean silt picked up by road sweeping machines active across the site, rather than this being removed to an off-site facility.
