By Howard Fielding and Mary Gentry GROUNDWATER. MANY PEOPLE have never heard of it, many take it for granted. Although hidden beneath the surface of the earth, groundwater is vital to everyone. About half of Louisiana's population relies on it for drinking water.
Groundwater supports farms, homes, and industries, and the quality of it shapes our economy and our environment. Nevertheless, out of sight, groundwater is often out of mind as well. Years of careless disposal of wastes and other human activities are posing significant threats to groundwater in many areas today. The results of this neglect are difficult to ignore. For example, in April 1992, the Village of Gilbert was forced to shut down both of its public water - supply wells due to benzene contamination from an abandoned service station. The cost of cleanup and well replacement is estimated at $1 million. Obviously, it is important that efforts be made to prevent groundwater contamination rather than suffer its consequences: a costly remediation process and possible health risks to the community. Section 1428 of the Safe Drinking Water Act Amendments of 1986 requires each state to submit to the U.S. Environmental Protection Agency a state program to protect wellhead areas from contaminants. A wellhead is the physical location of a well - that is, where the well reaches the surface of the earth. The term wellhead refers to public supply wells drilled into the earth for the purpose of obtaining potable water, or water suitable for drinking. DEQ was designated as the lead agency in Louisiana to administer the program, which was approved in March 1990. The fundamental goal of this Wellhead Protection Program is to protect wellhead areas from contaminants that may have adverse effects on human health. A wellhead protection area is the surface and subsurface area surrounding a well or wellfield through which contaminants are likely to pass and reach the well or wells. Most people are unaware of how groundwater actually gets into the ground, how it moves and reaches water wells, and how it can become contaminated. The focus of the Wellhead Protection Program is educating the public about potential sources of contamination of public water supplies.
An aquifer is an underground geologic formation that stores groundwater. An unconfined aquifer is one in which the upper boundary is formed by the water table, the level of groundwater beneath the earth's surface. This unconfined aquifer is the first saturated zone beneath the surface and is most susceptible to surface contamination since the water table is directly recharged, or replenished, by infiltration.
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