Oil and Gas at Your Door? (2005 Edition) - Earthworks

STAGES OF OIL & GAS DEVELOPMENT
PRODUCTION STAGE—ISSUES AND IMPACTS
Surface Disturbance
• Additional land disturbance may occur as a result of the construction of production facilities
and infrastructure such as compressors, pipelines, etc.
• Reclamation of areas disturbed during the drilling process should be conducted during the
production stage. This is known as interim reclamation.
Air Pollution
There are a number of pollutants that are associated with the production
stage. These include volatile organic compounds (VOCs), nitrogen oxides,
sulfur dioxide, carbon monoxide, benzene, toluene, ethylbenzene, xylene,
polycyclic aromatic hydrocarbons, hydrogen sulfide, particulate matter,
ozone and methane. For more information on these air emissions, read
about Impacts Associated with Oil and Gas Operations.
In 2001, the oil and gas industry in the U.S. vented and flared about 86
billion cubic feet of gas. 117 Not only do venting and flaring waste natural
gas (which should be a concern for mineral owner who would have
received royalties on the gas), these emissions also contribute to air pollution
and greenhouse gases in the atmosphere.
Venting of natural gas may occur during:
• Well testing.
• Oil and gas processing. Solution gases from oil wells, batteries or
tanks, and natural gas from compressor vents, instrument gas stations,
pneumatic devices, dehydrators and storage tanks may be
intentionally or unintentionally released.
• Pipeline maintenance operations. Prior to any work on a pipeline,
gases in the line are purged and may be vented directly to the atmosphere.
Flaring of natural gas may occur during:
• Well testing.
• Cavitation and hydraulic fracturing (see flareless completions in the
section on Alternative Technologies and Practices later in this chapter)
• Oil processing. It occurs at batteries where oil is processed and
stored. These flares burn constantly, because gas is a by-product of
oil production. Known as solution gas, this gas is the largest source
of flaring in Alberta, Canada. 118
• Gas processing. At processing plants, gas by-products that have no
market are burned off. Gas may also be flared during emergency situations.
• Pipeline maintenance operations. Prior to work on a pipeline, gases
in the line are purged and may be flared.
FIGURE I-19. VENTING OF GAS WELL
Source of methane, a greenhouse gas.
FIGURE I-20. FLARING DURING COMPLETION
OF A COALBED METHANE WELL.
Photo by OGAP.
It has been argued that flaring is better than allowing the gases to be
vented directly into the atmosphere because of the health threats posed
by some of these substances (e.g., H 2 S). While it is true that flaring can
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