Be careful, PCBs have been found to penetrate 10s of metres vertically
through the thick and apparently impermeable glacial till sheet covering
much of Canada. Travel faster than recharge by moving through
micrometre fissures.
A good source of conceptual understanding on DNAPL behaviour is The
Illustrated DNAPL Handbook:
http://publications.environment-agency.gov.uk/pdf/SCHO0604BHIT-e-e.pdf
David
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David Lerner +44 114 222 5743
Catchment Science Centre: www.shef.ac.uk/csc
URSULA urban rivers project: www.ursula.ac.uk
HNet hyporheic network: www.hyporheic.net
On 04/06/2010 2:44 PM, Lucy Hooper wrote:
> Thanks all, answers back up my initial thinking:
>
> They are very viscous oils.. don’t go very far at all.. 5m.. ish even in gravels.. I dug out a few hotspots of PCB in gravels a while back. They were only ever 2-3m by the same and only 1m deep and that was in a cable factory.
>
> The higher the soil organic content, the lower their mobility, as they will tend to adsorb to it more strongly. They are highly insoluble in aqueous media
>
> Low mobility... unless your PCBs are dissolved in an organic solvent or attached to organic matter content which is then reworked on your site
>
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