B-1.1, r. 2 - Construction Code

Full text
8.78. Every underground part of piping that is to contain petroleum products must, to be used, have a double wall that meets the requirements of section 8.28 and be connected at its lowest point with a liquid-tight collector well.
The collector well must, in addition, have an automatic leak detection system with a visual and audible alarm that meets the requirements of section 8.28.
O.C. 220-2007, s. 1.