WorldWide Drilling Resource®

Protecting Long Island’s Sole-Source Aquifer Adapted from Information by the New York Department of Environmental Conservation and the U.S. Geological Survey The New York State Department of Environmental Conservation Commissioner Basil Seggos announced a new monitoring well will be drilled in Freeport, Nassau County. This well is the first of 25 being drilled throughout the area to support a comprehensive groundwa- ter study of the Long Island sole-source aquifer system. Most of Long Island is completely dependent on groundwater from the underlying sole-source aquifer system. This system provides more than 400 million gallons a day of freshwater to over 2.8 million people in Nassau and Suffolk Counties. As the name suggests, it is Long Island’s sole source of water for the Island’s population. The Long Island Aquifer System is comprised of several freshwater aquifers ranging in increas- ing depth from the upper glacial, North Shore, Jameco, Magothy, and finally the Lloyd aquifer, which is a largely untapped layer containing the oldest water, some of which has been held in the Aquifer System for more than 5000 years. One of the main issues the study will focus on is saltwa- ter intrusion. Long Island is surrounded by salt- water at the surface and at varying depths below ground. The freshwater which replenishes the aquifer system, slowly flows through and eventually exits the aquifer system at the coast, keeping the saltwater in the sediments offshore from pushing landward beneath Long Island. The area where the fresh groundwater flowing seaward to the coast meets the salty groundwater flowing landward toward the shore, is called the 43 WorldWide Drilling Resource ® MARCH 2020 Diagram courtesy of New York Department of Environmental Conservation. Not to scale. WTR Protecting Long Island cont’d on page 48.