ASCE Policy Statement 539
Approved by the Energy, Environment and Water Policy Committee on March 22, 2012
Approved by the Public Policy Committee on May 4, 2012
Adopted by the Board of Direction on July 20, 2012
The American Society of Civil Engineers (ASCE) supports the exploration and production of oil and natural gas energy resources by means of hydraulic fracturing when based upon sound engineering and industry practices that protect public health, safety, and the environment. ASCE strongly recommends that current regulations be reviewed, revised or enhanced, as needed, to:
- Mandate full public disclosure of all chemicals and other propping agents in the fracturing fluid.
- Control the handling, use, and disposal of chemicals in the hydraulic fracturing process.
- Establish well construction and decommissioning standards to protect underground sources of drinking water and to prevent methane loss.
- Establish site closure and restoration standards.
- Reduce the freshwater footprint for each fracturing operation by reuse of the flowback fluid.
- Assure the safe treatment and disposal of used fracturing fluids, flowback fluid and producer well waters.
- Ensure adequate controls over stormwater runoff or overflow from the well site.
- Ensure that there is no surface infiltration of waste and production fluids into near-surface aquifers and recharge zones.
- Promote research on hydraulic fracturing, including the effects of multiple drilling operations in a single watershed.
- Protect in-stream water flows and determine the cumulative impact of multiple drilling operations within a single groundwater basin or watershed.
Hydraulic fracturing is a well-stimulation process used to maximize the extraction of underground resources, including oil, natural gas, and water. The oil and gas industry uses the process to enhance subsurface fracture systems to allow oil or natural gas to move more freely from the rock pores to production wells that bring the oil or gas to the surface. The process has been used to initiate oil and gas production in unconventional (low-permeability) oil and gas formations.
Production wells may be drilled in the vertical direction only or paired with horizontal or directional sections. Vertical well sections may be drilled hundreds to thousands of feet below the land surface and lateral sections may extend 1,000 to 6,000 feet away from the vertical well.
Fluids, commonly made up of water or gas, and chemical additives, are pumped into a geologic formation at high pressure during hydraulic fracturing. When the pressure exceeds the rock strength, the fluids open or enlarge fractures that can extend several hundred feet away from the well. After the fractures are created, a propping agent is pumped into the fractures to keep them from closing when the pumping pressure is released. All regulation of hydraulic fracturing is done by the states in the absence of federal rules.
After the fracturing process is completed, the internal pressure of the geologic formation causes the injected fracturing fluids to rise to the surface where they may be stored in tanks or pits prior to disposal or recycling. Recovered fracturing fluids are referred to as flowback. Disposal options for flowback include discharge into surface water, surface impoundment, or deep well injection. Surface water discharges of the flowback are regulated by the National Pollutant Discharge Elimination System (NPDES) program, which requires flowback to be treated prior to discharge. Treatment is typically performed by wastewater treatment facilities. When initial fracking operations are over, the well continues to produce oil and/or gas and water. This water continues to be discharged. These waters, called “producer water” have salinities similar to the initial frack water and must be managed over the longer term in accord with regulations, in an environmentally acceptable fashion.
Underground injection of flowback is regulated by EPA through the Underground Injection Control (UIC) program or a state with UIC enforcement authority. Under the Energy Policy Act of 2005, Congress exempted hydraulic fracturing from the underground injection control program requirements applicable to class II oil and gas related wells set forth in the Safe Drinking Water Act, except for when diesel fuels are used.
Regulation of hydraulic fracturing is necessary to ensure that the public health, safety, and welfare are protected from the potential for chemical contamination of underground sources of drinking-water and associated surface waters.
ASCE Policy Statement 539
First Approved 2012