RIASSUNTO
Abstract
Environmental stewardship has been and continues to be a critical component of the oil and gas industry, as exploitation of shale and other unconventional gas reservoirs requires large volumes of water for economic and efficient production. Evaluating and communicating the hazards of chemicals is done in a highly variable manner across the world. However the recent adoption of the Globally Harmonized System of Classification and Labeling of Chemicals (GHS) by multiple
Global regulatory bodies has brought international consensus to hazard criteria and definitions. This system is being implemented with REACH in the EU. In the US OSHA has just proposed the GHS criteria as the basis for modifying their hazard communication regulations. This standardization ensures information about hazards and toxicity of chemicals is more universally available, to enhance protection of human health and the environment during handling, transportation and use. It is this scheme that we are beginning to utilize as the basis for the ranking of products and systems.
This paper will describe the evaluation and implementation of a practical and quantitative process of ranking well servicing products based on their safety, health and environmental impacts. The ranking allows operators to select and use products that best fit their environmental stewardship goals, and provides scientifically sound tools for better research and development, and educational efforts.
Introduction
High-volume, high-rate hydraulic fracturing and horizontal drilling have unlocked vast potential reserves of natural gas in North America and throughout the world. However, as with most industrial efforts or processes, shale gas and oil exploitation does not come without manageable risks. In this case there is the concern of managing the depletion of valuable natural resources such as fresh water. This concern includes the perceived potential risk that chemicals used in the fracturing process could enter underground safe drinking water (USDW) reservoirs.
Extensive studies of hydraulic fracturing by the United States Environmental Protection Agency (EPA, 2004), independent interstate advocacy groups such as the Ground Water Protection Council, the Interstate Oil and Gas Compact Commission and state regulatory agency-sponsored studies (NY Department of Environmental Conservation, 2009) have found that hydraulic fracturing does not pose an unreasonable risk to subsurface drinking water supplies. Nevertheless, oil and gas companies, responsible for the development and transmission of natural gas to the market place are always seeking to utilize increasingly safer, technologies in oil and gas operations, including chemical application during hydraulic fracturing. However, current environmental guidelines for hydraulic fracturing in the United States are based predominately upon well construction controls and evolving state regulatory requirements.