The Ontario Building Code | Sampling of Treatment Units
8.9.2.4. Sampling of Treatment Units
(1) Every person operating 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,
(a) take a grab sample of the effluent to determine the level of CBOD5 and suspended solids in the effluent,
(b) carry out the sampling required by Clause (1)(a) in accordance with the methods described in the APHA/AWWA/WEF, "Standard Methods for the Examination of water and Wastewater", and
(c) promptly submit the results of the sampling required by Clause (a) to the chief building official.
(2) Except as provided in Sentence (4), the sampling required by Sentence (1) shall be conducted,
(a) initially, once during the first 12 months after the sewage system was put into use, and
(b) thereafter, once during every 12 month period, at least 10 months and not more than 18 months after the previous sampling has been completed.
(3) The concentration of CBOD5 and suspended solids in the grab sample described in Sentences (1) and (4) is deemed to comply with the maximum concentration requirements set out in Table 8.6.2.2. when it does not exceed 20 mg/L for each of these parameters.
(4) If the results of the sampling required by Sentence (1) do not comply with Sentence (3), the person operating the treatment unit shall,
(a) resample the effluentin accordance with Clauses (1)(a) and (b) within 6 months after the previous sampling has been completed, and
(b) promptly submit the results of the resampling required by Clause (a) to the chief building official.
In Plain Language
Treatment units within these systems must be sampled periodically as set out in this article, checking that the treatment process is actually working as designed.
This is a plain-language summary of the 2012/2017 Ontario Building Code text above, for general understanding only and not a substitute for the Code. Always confirm current requirements against the 2024 edition (O.Reg. 163/24) or a qualified professional before construction.