36.1. Low permeability soil: Where the soil of a disposal site is low permeability soil, the above-ground sand-filter bed must be built with a low pressure feed system.
If a non-watertight secondary treatment system is installed above an above-ground sand-filter bed, a low pressure feed system is not required if the treatment system ensures a uniform distribution of the hydraulic load over the seepage surface. The distribution method must be provided in the manufacturer’s manuals and have been certified by an engineer who is a member of the Ordre des ingénieurs du Québec.
O.C. 786-2000, s. 36; O.C. 567-2008, s. 8.