Managing stray gas is the subject of a fourth guidance document from the Marcellus Shale Coalition, issued October16th. The essentials of this article were compiled by Pam Kasey as published by the State Journal.
In its three-page “Recommended Practices: Responding to Stray Gas Incidents,” the Pennsylvania-based natural gas industry group lays out simple guidelines for oil and gas operators that can also inform the public about what to expect when an incident occurs.
Stray gas can originate from sources including coal beds, oil and gas wells, landfills, pipelines and microbial sources. It can migrate from there into groundwater, surface water, soil and structures, the MSC points out. The industry has frequently identified the presence of stray gas during pre-drill baseline water surveys, according to a media release accompanying the guidance document.
The document aims to provide detailed steps that operators can take when stray gas is encountered: from developing proper plans of action to notification of regulators as well as initial response actions and performing site reconnaissance surveys. When stray gas is detected in a structure, depending on the level, oil and natural gas producers may install ventilation and methane-specific alarms as a precautionary measure.
Where elevated levels of methane are detected in water wells, ventilation may also be considered. When methane is detected in a water source servicing a structure, the operator should consider providing an alternate water source until additional testing determines the source of the stray gas.
The document prioritizes public and employee safety and the prevention of damage to property and the environment and emphasizes the importance in responding to an incident of maintaining lines of communication with state regulators, local officials, first responders and homeowners.
“For the most critical situations,” the document reads, “immediate action should be taken to protect public safety and property. These measures may include evacuation and/or ventilation procedures. Because operators do not have the authority to initiate an evacuation, notification and cooperation with local emergency response organizations is critical.”
The MSC has previously released recommended practices on (1) site planning, development and restoration; (2) supply chain; and (3) pre-drill water supply surveys.