270. The authorization holder must, before the permanent closure of the well, conduct a flow test at the surface casing vent flow to determine if fluid is escaping from it.
A bubble test must be conducted using a pipe submerged at 2.5 cm under the water for at least 10 minutes. If, during that period, bubbles are present, the well is considered to have flow at the surface casing vent flow.
In such a case, the holder must
(1) conduct a flow test of that flow until a stabilized flow is obtained; and
(2) close the surface casing vent flow until a stabilized pressure is obtained.
The pressure is considered to be stabilized if, over a 6-hour period, the change in pressure is less than 2 kPa/h.