Cranleigh Blog

Leachate Lagoon... Leachate La-Gone

With the wet weather holding off until late November and the recent dry period we have managed to make more progress than expected. We have continued to gain better control over the site’s leachate production.  
Firstly, we have extended the clay cap over the middle of the site, so rainwater will run over the surface of the clay layer rather than percolating through the ground into the contaminated soils below.
Secondly, we have placed silt traps along the waterways inside the site so clean runoff water leaving our site has less silt in it. This is important as silt can be detrimental to streams, suffocating flora and fauna further downstream.
Finally, we have finished the ‘cut-off’ along the eastern edge of the brick shed. The ‘cut-off’ is a compacted strip of clay that goes into the virgin ground that acts as barrier for water that is seeping beneath the shed to join the contaminated water elsewhere on the site.
With more control over the volume of leachate we have been able to create a clay bank to separate the lagoon to allow access to the sludge.
UKPN visited the site in early February to divert power away from the substation in the corner of the brick shed and to re-route electric cable that had been hampering progress. Now all the electric cable buried onsite have no power running through them. This is part of a 3-phase plan to remove all original powerlines from our site, so we can continue with our capping programme. Phase 2, due to take place in mid-March, will bring the power cable back into the site through a new substation that will provide the power for the eventual 19 houses. The final phase, set for mid-spring, will be to move the overhead line that currently runs through the site to underground cables that will run along the current footpath of the site.