Class 4 Sewage Systems

(1)This Section applies to the construction of a Class 4 sewage system.

(1)The treatment unit shall be connected to a leaching bed constructed in accordance with the requirements of Section 8.7.

(1)Where the total length of distribution pipe or leaching chamber required is 150 m or more, the sewage system shall have at least one pump or a siphon contained in a dosing tank that may be a separate compartment within the tank structure, for distribution of the effluent.

(2)Where the total length of leaching chamber is 150 m or more, a distribution pipe shall be installed at the centre line of the leaching chamber and extend the total length of leaching chamber to allow for dosing of the effluent.

(3)Alternating siphons shall not be installed in a sewage system.

(4)Where 2 or more pumps are employed within a dosing tank, the pumps shall be designed such that the pumps alternate dosing, and dosing shall continue in the event that one pump fails.

(5)Where a pump or siphon is required, the pump or siphon shall be designed to discharge a dose of at least 75% of the internal volume of the distribution pipe within a time period not exceeding 15 min.

(6)Where a pump or siphon is required, the pump or siphon shall be equipped with a device that shall produce an audible and visual alarm signal that indicates a high water level in the pump or siphon chamber.

(1)An effluent filter shall be installed in the outlet flow path of every septic tank that discharges effluent to a leaching bed.

(2)The septic tank effluent filter required by Sentence (1) shall,

• (a) conform to the requirements of NSF/ANSI 46, "Evaluation of Components and Devices Used in Wastewater Treatment Systems,"
• (b) be sized to filter particles of 1.6 mm,
• (c) have a minimum area of 550 cm2, and
• (d) be installed in accordance with the manufacturer's recommendations.

(3)A secured access opening to allow for regular maintenance of the effluent filter shall be provided at the ground surface.

(1)Except as provided in Sentence (2), a treatment unit, other than a septic tank, shall be designed such that the effluent does not exceed, for the level of the treatment unit set out in Column 1 of Table 8.6.2.2., the maximum concentrations set out opposite it in Columns 2 and 3 of Table 8.6.2.2.

(2)A treatment unit that is used in conjunction with a leaching bed constructed as a shallow buried trench, Type A dispersal bed or Type B dispersal bed shall be designed such that the effluent does not exceed the maximum concentrations set out opposite a Level IV treatment unit in Columns 2 and 3 of Table 8.6.2.2.

(3)All treatment units referred to in Sentences (1) and (2) that contain mechanical components shall be equipped with an audible and visual warning alarm so located to warn the occupants of the building served or the operator of the treatment unit of a malfunction in the operation of the treatment unit.

(4)All treatment units referred to in Sentences (1) and (2) shall permit the sampling of the effluent.

(5)A treatment unit is deemed to comply with Sentences (1) and (2) if it has been certified to CAN/BNQ 3680-600, "Onsite Residential Wastewater Treatment Technologies" using a temperature condition listed under option a) or b) of Clause 8.2.2. of that standard.

(6)Every operator of a treatment unit shall obtain, from the manufacturer or distributor of the treatment unit, literature that describes the unit in detail and provides complete instructions regarding the operation, servicing, and maintenance requirements of the unit and its related components necessary to ensure the continued proper operation in accordance with the original design and specifications.