BAM Nuttall were carrying out work as part of the M1 widening scheme. During works our client was granted a permit to discharge 2 m³/day of treated concrete washwater into a motorway drainage channel which linked into a surface watercourse.
The Overall Objective
Washdown waters from the onsite batching plant and the 7 no. lorries that were feeding the slipform paving machines on the motorway, were held in a catchpit.
At the end of each day 2 m³ of water was transferred into the water holding tank and treated using the pHD unit ready for discharge to the surface watercourse in the morning.