Abstract
Hydraulic fracturing processes have recently been the subject of increasing scrutiny with particular concern directed towards protection of water resources. Operators and fracturing services companies in the United States have been targeted by both federal and state legislators and the EPA with audits, inquiries, and regulations requiring disclosure of the chemicals pumped in fracturing treatments and banning the use of certain chemistries, such as diesel oil. Much effort has been expended to identify alternative, more environmentally acceptable products which maintain the needed material performance characteristics and cost basis.
A new quantitative process based upon the Globally Harmonized System for Classification and Labeling of Chemicals (GHS) has been employed to evaluate and rank the hazards posed by various treating fluid additives and potential alternatives. The GHS is a process is which has been adopted by the United Nations to standardize information regarding the hazards and toxicities of chemicals. Once the respective material hazards have been quantified, they may be ranked for comparison with like-purposed additives for their anticipated safety, health, and environmental impact. The best candidates by that measure may then be assessed for performance and cost. The process has become a valuable tool to guide fracturing R&D and oilfield chemical suppliers toward development of more environmentally acceptable products and systems.
The progress towards the objective of full implementation of environmentally acceptable chemistries in fracturing applications is documented. Working examples of the more acceptable chemical additive selections resulting from the applications of the hazard assessment process are provided. Furthermore, the migration to more environmentally responsible fracturing processes through quantification of hazardous risk "removed" from applications by replacement with more favorable alternatives is discussed.
The fruits of the process will be discussed in this endeavor, providing working examples of the chemical additive selection. Furthermore, the progress to more environmentally responsible fracturing processes through quantification of hazardous risk ‘removed’ from applications, i.e. amount of hazardous material removed by replacement with more favorable alternatives.
