In fact, surface casing vents are literally designed to be a relief, a pressure relief. In addition, to several layers of casing and cement a safety device called a casing vent is installed on every well. The casing vent is designed to vent natural gas normally found in farmer wells and other natural gas seeps near surface. It is also designed to detect any deep gas leaks that while uncommon can develop in the casing and cement. Monitoring of the casing vents allows us to determine whether natural gas is of the normal surface seep variety common throughout the Lowlands or the not very common deep gas sort.
Surface gas is common in Quebec and can be found, for example, at the well known la Fontaine du Diable. It is completely normal to have small low pressure vent flows especially in areas such as the Lowlands that naturally has shallow natural gas seeping in to wells and to surface. By relieving the pressure and detecting and fixing deep gas leaks we protect farmers’ wells. It is good to know our surface vents are working according to design which is why we monitor them. The public must also be relieved to find that the MNRF is doing its job and monitoring this issue as they should.
By the way, one of Questerre’s wells is mentioned by the MRNF. Barely enough gas to measure flowed through this well when it was wide open. We are sure the amounts are insignificant relative to either safety or greenhouse gas emissions when it is closed.