1. Erica Davey, Ellie Hoffman, Lisa Vienckowski R EMEDIATION OF THE 2012 L ONDON O LYMPICS S ITE

2. L ONDON O LYMPIC S ITE  2.5km 2 Site in East London’s Lea Valley  Over 800,000 cubic metres of contaminated soil  Over 20 million gallons of contaminated groundwater

3. W HAT W AS T HERE ?  Oil  Lead  Petrol  Tar  Cyanide  Arsenic  Low Level Radioactive Waste

4. H OW D ID I T G ET T HERE ?  Contaminated through centuries of industrial use, including:  Unregulated Landfill Site from the Victorian Era  Cosmetics, Soap and Lavender Factory  Calico Printers and Porcelain Factory  Petrol Factory  General Use and Dumping

5. W HY T HIS S ITE T HEN ?  Vision ‘to make a real change in London, across the UK and globally.’  Olympic Park surrounded by ‘some of the most diverse – and most deprived – communities in the country.’  Edge of the Thames Gateway Project – biggest regeneration project in Europe

6. P OSSIBLE S OLUTIONS  Site Flushing  Soil Vapor Extraction  Thermal Treatment  Soil Washing  Bioremediation

7. S ITE F LUSHING  Large volume of water and chemicals used to raise water table  Removes NAPLs  Advantages  Relative fast and inexpensive  In situ  Disadvantages  Can be expensive/difficult if many wells/chemicals needed  Handling chemicals can be dangerous  Chemicals left behind after cleanup may be harmful

8. S OIL V APOR E XTRACTION  Vacuum used to remove volatile and semivolatile organic compounds from the vadose zone  Special equipment separates clean air from vapors  Advantages  In situ  Works well when combined with air sparging  Air used encourages growth of microbes  Safe, relatively quick and simple  Cleans both soil and groundwater

9. T HERMAL T REATMENT  Different methods and techniques that apply heat to polluted soil and/or groundwater to destroy or volatilize organic chemicals  Used for DNAPLs or LNAPLs  Advantages  In situ  Works in clays where other methods may not  Can reach pollution in deep areas  Disadvantages  Less certainty about uniformity of cleanup  Gases may pollute air- use cover

10. A DOPTED S OLUTIONS  Soil washing, bioremediation, soil stabilisation/immobilisation, thermal desorption, and dredging and sediment treatment were all used.  Soil washing and bioremediation were the primary methods for cleaning the soil.  In an effort to be green, site remediation occurred mainly onsite.

11. S OIL W ASHING  Approximately 500,000 tonnes of soil were treated to remove primarily hydrocarbons and heavy metals.  50-tonne soil washing machines were used to treat the soil onsite.  Soil washing separates the soil based on particle size.  Separation of soil typesminimisesthe amount of soil that needs to be treated. http://www.epa.gov/tio/download/citizens/soilwashing.pdf

12. On site soil washing machine in action http://www.london2012.com/photos/2009/04/soil-washing-machine-53368.php

13. B IOREMEDIATION  50,000-tonnes of oil and petrol contaminated soil were cleaned using bioremediation.  Bioremediation was used to remove contaminants that weren’t removed through soil washing.  Microorganisms use natural processes to remove harmful chemicals.  Bioremediation is applicable for a wide range of contaminants.  Bioremediation was performed above the ground because the soil had already been removed for soil washing.

14. F ACT F ILE, UP UNTIL S EPTEMBER, 2009  Nearly 3000 site investigations carried out into contamination.  More than 200 buildings demolished  Approximately six million hours worked  Over 80% of 800,000 cubic metres of contaminated soil cleaned and reused.