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We wish to reply to the question, “Does hydraulic fracturing or fracing, as it is called in the industry, with hazardous chemicals present a threat to the environment and ground water supplies?” An appropriate answer requires a discussion of the ingredients that are used in the fracing process and a description of the fracing process itself. For starters, the process consists of the injection under high pressure of a mixture or solution of water and sand along with a relatively small volume of chemicals into a formation for the purpose of creating a multitude of fractures in that formation. The water and sand comprise 99 % by volume and the chemical additives amount to about 1%. The water serves as the transporting medium, while the sand serves as a propping agent, which holds the fractures open after the fracing has been completed. The purpose of the high pressure is two fold; to create sufficient force to break the formation and cause the fractures, and to create a stream velocity sufficient to keep the sand entrained as it is transported into the formation. The ingredients that comprise the fracing fluid, other than the water and sand, are specifically selected chemicals to assist in assuring the highest efficiency of the fracing process. In a typical frac job those chemicals would be as follows: Gel Agent Guar gum or hydroxyethyl cellulose----------thickening agent Bactericide Glutaraldehyde-----------------------eliminates harmful bacteria Acid Hydrochloric acid------------dissolves minerals/initiates cracks Inhibitor Formamide---------------------prevents corrosion of well casing Crosslinker Borate salts-------------------------------maintains fluid viscosity Friction agent Petro distillate-----------------reduces water friction/slick water Stabilizer Potassium chloride----prohibits fluid invading formation clays pH agent Potassium carbonate----------assists crosslinker and other agents Surfactant Isopropanol-----------------reduces surface tension of frac fluids It should be noted that all of these chemical additives are typically used in everyday products such as hair coloring, medical disinfectants, laundry detergents, swimming pool cleaners, pharmaceuticals, cosmetics, household cleaners, deodorants, plastics, and antiperspirants. They have been proven through these many uses to pose no risk to the environment, nor to the men and women who use them. These are not hazardous chemicals. In the typical frac job, a well is drilled and cased to the depth of the target formation using a surface string of casing, an intermediate string of casing and finally a production string. The surface string is placed in drilled hole deep enough to have passed through any and all aquifers. Cement is then introduced into this casing and forced out the bottom or shoe of the casing and on up the outside of the casing until the cement reaches the surface. This cement is then allowed to dry, providing a bond between the wall of the drilled hole and the outside of the casing. A test is made of this cement job to be sure that it has isolated the aquifers and all other formations from each other behind the surface casing. The operator then proceeds into the hole with another bit of smaller size and drills the intermediate hole to some programmed depth above the target formation. Then the intermediate string of casing is lowered into that hole and cemented back up to the shoe of the surface string of casing to provide isolation of all the formations behind that intermediate string from each other in a manner similar to the cementing of the surface casing. After that cement job has dried, the operator goes inside the intermediate casing string with a new smaller bit and drills out the shoe of the intermediate string and proceeds to drill down through the target formation to the programmed total depth. The final production string of casing is then run in this hole and cemented back up to the shoe of the intermediate string. When that cement is dried, the operator goes inside the production string with a smaller bit to drill out the cement remaining inside the production string to a depth sufficient to allow the perforation of the target formation. It is important to note here that the production string may be in a vertical hole or at the operator’s election in a lateral leg or horizontal leg of the well. The cementing process is essentially the same for a vertical or horizontal leg of the well. When the inside of the production string has been cleaned out, the perforation process begins. In shale wells particularly, the perforating may be in several sets or stages, which allows the frac job to be done in stages. This is more effective than to try to perform and effective frac job on one long set of perforations for the whole producing formation. When the frac job has been completed the frac fluids are allowed to flow back up to the surface along with the gas that will now be flowing out of the shale formation. All of these flow back fluids are directed into carefully lined pits or into containing tanks brought to the well site for this purpose. At the surface the gas is separated from the liquids and portions of the sand that also flow back, and the gas is normally flared until the well clean up period is concluded. Great care is given to the containment of the liquids which are either transported to the next well location for use in a frac job on that well or sent to a processing plant where the water is stripped of its impurities and returned to other uses. Now the frac job has been directed at a formation thousands of feet below the aquifers that are isolated behind the surface casing and there is no possibility of those frac fluids coming in contact with those aquifers or any other source of potable water. In fact, through the 60 year history of hydraulic fracturing there has never been a verified case of any contamination of aquifers or other water supplies from hydraulic fracturing. It is really easy to see why, since there are thousands of feet of cemented casing separating the frac fluids from the aquifers.