Onsite wastewater system nitrogen contributions to groundwater in coastal North Carolina.
The objective of the study described in this article was to evaluate the nitrogen contributions from two onsite wastewater systems (sites 1 and 2) to groundwater and adjacent surface waters in coastal Beaufort County, North Carolina. Groundwater levels and water quality parameters including total nitrogen, nitrogen species, temperature, and pH were monitored from October 2009 to May 2010. Nitrogen was also tested in groundwater from deeper irrigation or drinking water wells from the two sites and six additional neighboring residences. Mean total nitrogen concentrations in groundwater beneath onsite wastewater systems 1 and 2 were 34.3 +/- 16.7 mg/L and 12.2 +/- 2.9 mg/L, respectively, and significantly higher than background groundwater concentrations (< 1 mg/L). Groundwater in the deeper wells appeared not to be influenced by the onsite systems. Groundwater nitrogen concentrations typically decreased with distance down-gradient from the systems, but were still elevated relative to background conditions more than 15 m from the systems and near the estuary. This was a pioneering effort to better understand the link of onsite systems, the fate of nitrogen in the environment, and public health.
Environmental Health Sciences Program, East Carolina University, USA.
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Humphrey
Department of Geological Sciences, East Carolina University, USA.
M A
MA
O'Driscoll
North Carolina Department of Health and Human Services, USA.
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NE
Deal
Department of Soil Science and Cooperative Extension, North Carolina State University, USA.
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Lindbo
Department of Geological Sciences, East Carolina University, USA.
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SC
Thieme
Environmental Health Services Branch, Centers for Disease Control, and Prevention, Atlanta, GA 30341, USA.
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MA
Zarate-Bermudez
D004784:Environmental Monitoring; D060587:Groundwater / Q000032:analysis*; D009584:Nitrogen / Q000032:analysis*; D009657:North Carolina; D014865:Waste Disposal, Fluid; D014874:Water Pollutants, Chemical / Q000032:analysis*
D014874:Water Pollutants, Chemical; D009584:Nitrogen