Key potential environmental impacts

Air

Flaring and venting

Flaring is the controlled burning of natural gas at a well site or facility; venting is the release of uncombusted natural gas to the atmosphere.

With production of natural gas from unconventional sources, because natural gas is the primary commodity, flaring is generally only carried out during the testing period, and only if there are no pipelines available to receive the gas produced during testing.

With oil production, most flaring and venting involves the burning of "solution gas," natural gas that is dissolved in oil, and which comes out of solution as the oil is produced. If the amounts of solution gas are small, they are flared, otherwise the gas is recovered.

In both cases, industry must meet or exceed the regulations in place for flaring. As well, industry makes every effort to minimize flaring because it poses a hazard and it results in the loss of saleable product.

What is industry doing?

• voluntary action
  

  In Alberta, where most of Canada's oil and gas operations are concentrated, the industry has helped to develop strategies to reduce flaring and venting. Since 1994, the industry has participated in the Clean Air Strategic Alliance (CASA), a multi-stakeholder group that deals with air quality issues in the province. In 1998, industry helped develop a CASA framework for reducing and managing flaring and venting in Alberta. This framework included a provincial target to reduce routine flaring of solution gas in 2001 by 25 per cent below 1996 levels.

  This framework was reviewed in 2001, and new targets set, as the original targets had already been exceeded. By the end of 2003, a province wide effort by the industry had resulted in a 70 per cent reduction in flaring below 1996 levels. Venting of natural gas was also included and by the end of 2003 a 38 per cent reduction below venting levels in 2000 was reached.

• operational changes
  

  Changes in procedures and equipment in natural gas operations reduce the need for flaring during "upsets" and maintenance. Some plants have been reconfigured to process gas that does not meet pipeline specifications. Previously, this "non-spec" gas was flared. New well-testing methods also reduce the duration of flaring. If there are nearby pipelines to processing plants, the test gas can be sent to the plant rather than flared.

• new technology
  

  New technologies such as small gas-fired mini-turbine generators can produce electricity from gas that would otherwise be flared.

• research
  

  Industry sponsors research that boosts operating efficiencies and provides better understanding of environmental impacts. For example, a group of sponsors, including the industry and the Alberta and Canadian governments, participated in a three-year, $3.3-million study to improve the combustion efficiency of flares. The industry also supports the Western Inter-Provincial Scientific Study Association, a $19-million study looking at the possible impacts of solution gas flaring on livestock health in the four western provinces.

Many of the same technological and conservation measures also contribute to lower venting emissions. For example, industry is exploring opportunities to burn solution gas as fuel for small electrical generating units to reduce venting of methane and flare.

Sour gas and volatile organic compounds in relation to natural gas from coal

What is the issue?

Hydrogen sulphide and aromatic compounds in natural gas and crude oil create noxious odours and can be fatal in large enough concentrations. However, natural gas sourced from coals generally contains no hydrogen sulphide. In the rare cases where NGC (coalbed methane) is associated with hydrogen sulphide, the hydrogen sulphide is likely sourced from other zones.

In the majority of reservoirs, because NGC is almost pure methane, aromatic compounds and other components commonly found in emissions from conventional natural gas are not present when NGC is flared.

What is industry doing?

Industry is disseminating information regarding the composition of NGC.

Enhanced recovery of natural gas from coal using carbon dioxide

What is the issue?

Carbon dioxide is a greenhouse gas and as such, carbon dioxide emissions from the burning of fossil fuels may contribute to climate change. Various ways of removing carbon dioxide from industrial emissions and storing it underground are being examined.

What is industry doing?

The Alberta Research Council in conjunction with private industry and research organizations is researching carbon dioxide-enhanced recovery of NGC (coalbed methane) in unminable coals. The process involves injecting carbon dioxide into the coal to displace NGC from pores, fractures and coal surfaces while simultaneously storing the carbon dioxide. Carbon dioxide-enhanced recovery of NGC not only helps produce an environmentally friendly energy source, it helps in reducing CO2 emissions.

Release of methane into the atmosphere as a result of disassociation of gas hydrates

What is the issue?

Methane is ten times more potent as an agent of global warming than is carbon dioxide. Disassociation of gas hydrates and the consequent release of underlying natural gas could have a negative impact on the environment.

What is industry doing?

To date, there has been no commercial production of gas hydrates. Industry is currently researching ways to produce gas hydrates, or the conventional reservoirs underlying them, without disturbing the high-pressure, low-temperature environment under which hydrates are stable.