Chapter 26 Water quality issues in the outer coastal plains: New Jersey

Abstract New Jersey is the most densely populated state in the US and yet it is home to one of the most pristine groundwater resources in the country, the Kirkwood–Cohansey Aquifer System. This chapter discusses some of the activities that affect water quality in New Jersey's coastal plains. The most significant activities are human induced and they include excessive groundwater withdrawal and the addition of non-point and point source contaminants. The effects of those human activities that alter surface soils in ways that promote the movement of chemicals to streams and groundwater is included. The chemicals addressed include point source contaminants coming from superfund sites, landfills, underground storage tanks (USTs), sewage facilities, stormwater runoff facilities, storage lagoons, and other “state permitted” discharges. The contaminants include nitrates (NO 3 − ), phosphates, pesticides, some chlorides and trace metals, and many volatile organic compounds (VOCs). Some of these come directly from their natural or human-induced deposition on the surface or come about because of the secondary impact of these deposited chemicals on surface soils and sediments. Well water withdrawals have also altered the pre-development groundwater and surface water flow patterns. Chlorides from brackish bays and tidal rivers and from the ocean itself have recharged coastal plain aquifers in Raritan Bay, Delaware and along the Atlantic Ocean. These pumping centers are also drawing chlorides and other ions from saline groundwater coming from deeper aquifers. In addition, VOCs and Fe have recharged underlying aquifers from contaminated rivers and point sources toward these pumping centers.