145. The owner must conduct leak detection tests on underground tanks and piping in accordance with the second paragraph of section 8.130 of Chapter VIII of the Construction Code (chapter B-1.1, r. 2) each time one of the following occurs inexplicably:
(1) a volume loss of at least 0.5% of the petroleum products removed from a tank or a number of tanks containing the same product over a period of 1 month;
(2) a loss of petroleum products over at least 5 consecutive days;
(3) a loss of petroleum products over at least 18 days in a month, if the product level is measured every day;
(4) a loss or gain of petroleum products over at least 15 days in one month, if the product level is measured 6 days a week; or
(5) the water level in the bottom of the tank exceeds 50 mm.
If the leak detection test indicates a leak, all defective components in the installation must be repaired or replaced and another leak detection test must be conducted.