Emissions Related to Hydraulic Fracturing

The hydraulic fracturing process is part of the completion phase of a well.  It stimulates the reservoir to unlock large reserves of natural gas held in shale or other normally impermeable reservoirs.  This unconventional process requires a unique set of steps in addition to the drilling phase of a conventional process.

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The hydraulic fracturing process requires on average 3-7 millions gallons of water for the completion of the well.  In many instances the water must be trucked in to the remote drilling sites.  This increased amount of truck traffic causes increased air emissions from the truck engines as well as an increase in particulate matter from the use of unpaved roads.  

VOC Emissions

After the hydraulic fracturing process is completed, the frac fluid is allowed to flow back to the surface for recovery.  During this time the natural gas that flows back can contain volatile organic compounds(VOCs).  Each state regulates these emissions with EPA approval to ensure the well is operating within federal air quality standards. In addition to this some companies have utilized Green Completions.

Reducing Air Emissions

Reducing the environmental footprint of a hydraulic fracturing well can be accomplished with reducing the amount of water, as well as reducing the amount of sites the well sites are being drilled from.  The use of multiwell pad drilling as well as the recycling of frac water has shown to greatly reduce the amount of trucks need for the well site.  Manufacturers of diesel engines are required to meet many regulations from the EPA.  According to the EPA, emissions from new diesel engines has been reduced by approximately 75% in the last ten years, and will be reduced by another 90% within the next five to six years.