Washing out ready-mixed concrete trucks on-site
Ready-mixed concrete trucks should not be allowed to wash out anywhere other than the areas designated for the purpose. Purpose built wash-out skips are commercially available. Further guidance can be found at:
https://brmca.org.uk/documents/BRMCA_Best_Practice_Managing_Concrete_Wash_Waters_on_Site_31_October_2012.pdf
&
https://www.gov.uk/government/publications/treating-and-using-water-that-contains-concrete-and-silt-at-construction-sites-rps-235/treating-and-using-water-that-contains-concrete-and-silt-at-construction-sites-rps-235
Acknowledgement: Concrete Society