36. Installation conditions: Where the effluent of a treatment system is carried towards a soil absorption system and a soil absorption field or seepage bed may not be built because it is impossible to comply with section 17 or 26, the treatment system may be connected to an above-ground sand-filter bed insofar as the disposal site complies with the following standards:
(a) the soil of the disposal site must be high permeability, permeable or low permeability soil;
(b) the bedrock, underground water or any layer of impervious ground must be at least 60 cm below the surface of the disposal site;
(c) the grade of the disposal site must be equal to or less than 10%.