Some of you have commented on the final sentence in the previous post which reads: Image above taken of Misson Springs drilling rig, 11th March 2019, shows drilling rig in foreground and gas vent to atmosphere (presumably also effervescing gas) in background.
It should be noted that this sentence was not from IGas, rather from this writer!
I am rather hung up about methane venting or perhaps better described free gas emission to atmosphere (Environment Agency (EA) definition see below) that undoubtedly occurs during drilling. My view is that such flows from the vent stack on the mud gas separator should be metered. It is not beyond the wit of man, or indeed exploratory drillers, to install a gas flow measuring device on the vent stack (venturi perhaps) to measure the gas as it exits the vent stack. Perhaps the gas flow is already measured somehow. That gas flow has an impact on global warming, it affects us all and the volumetric flows from hydrocarbon drilling operations should thus be made public.
We have consulted the EA about our concerns on free gas emissions during the drilling phase at Tinker Lane and their response, to clarify the issue, follows:
“However, if you are concerned about how any gas encountered in an exploratory borehole during the drilling phase is managed then the following extra information may help explain how this would be dealt with if any were encountered during the drilling process.
In general terms venting may be considered as an option for managing gas from an exploratory borehole only if it was carried out in a managed and controlled way and only if the quantities involved were below the threshold whereby using another form of abatement such as using a flare would be feasible.
Waste gases, including fugitive emissions, are considered an ‘extractive waste’ underthe Mining Waste Directive. As such the management of fugitive gas emissions is reflected in the mining waste permit that was issued for the site.
Operators submit a Waste Management Plan as part of their permit application which sets out measures to control the waste on site to make sure it does not escape in an unmanaged fugitive way.
The Operator provided a specific risk assessment for this scenario which includes monitoring and proposes abatement and emergency control measure specific to gas management. These included:-
- mud weight will be adjusted as required to control formation fluids and pressures;
- a blow-out preventer will be in place while drilling against formations withpotential to produce hydrocarbons;
- monitoring of surface returns will be undertaken to detect gas and oilcontamination;
- monitoring of methane using an explosive atmosphere monitor. We have no evidence to suggest there were any quantities of “free” gas found duringthe drilling of the borehole at Tinker Lane that required the deployment of these control measures.