Information on reports on minor natural gas emanations

07.01.2011

Media reports have recently commented on some minor natural gas emanations that have been observed during regulatory inspections.  We wish to confirm that wells are regularly monitored by the companies that operate them, as well as by government regulators.  QOGA members always test the equipment they install in these wells, in particular the casing that protects the water table.

In natural gas development, there is a limited potential for gas or liquid to flow up to the surface of a well. This is known in the industry as surface casing vent flows (SCVF) and gas migration (GM). The primary concern with these types of gas flows is safety.  In this regard, it is important to be aware that at no time was there any danger to the public or workers as a result of these flows.

Identifying and managing SCVF and GM flows is a well-established and regulated practice in the industry.  Wellheads are equipped with a surface casing vent which allows natural gas to be released safely to the atmosphere and monitored by the operator.  Surface casing vent flows are tested prior to the initial completion of the well and routinely throughout the life of the well. If a SCVF is identified, it is reported to the Ministère des Ressources naturelles et de la Faune and further investigation is conducted.  Flows are categorized and appropriate corrective actions are determined in consultation with the regulator and in accordance with standard industry practices.  In most cases, the risk is so low that only monitoring is required, immediate repair is not necessary and corrective action is deferred until well abandonment.  This is consistent with all gas producing jurisdictions in North America.

It is important to recognize, that the presence of natural gas at surface is not necessarily an indication of SCVF or Gas Migration.  In Quebec and in other jurisdictions, it is not unusual for natural gas to be naturally present in shallow soils and aquifers. Natural gas is often found in water wells, independent of oil and gas activities.  In some cases, this gas can flow to surface using the well as a pathway.

Protecting the population, workers, and the environment is a very important concern for our industry. That is why we work under strong safety standards. No industry is risk free. However, the risks in the natural gas industry are very well known, as are the solutions and protective safety and environmental measures to address these risks.  Regulatory standards for these issues and others are in place in many other areas.

What causes SCVF or gas migration?

Identifying and managing SCVF and GM flows is a well-established practice in the industry.  It can occur when there is an incomplete seal between the steel casing and the cement or the cement and the surrounding formation. This can create a pathway for gas to flow to the surface.  While venting does release gas safely to the atmosphere, the GHG emission from these flows is not significant and is well understood in all regulated and mature gas producing regions.

Bureau d’audiences publiques sur l’environnement (BAPE) commissioners are currently drafting their report which will lead to enhancing the current regulatory framework for Quebec’s shale gas industry. The BAPE will make recommendations to the government by the end of February.  We look forward to a strong safety and regulatory framework that will govern our industry, which, it should be noted, will still be in the exploration phase for a few more years.