Nitrate Removal for On-Lot Sewage Treatment Systems: The POINT System

Nitrate-nitrogen (NO3-N) in groundwater is becoming a ubiquitous problem, particularly in rural and suburban areas where domestic water supplies are obtained from individual on-lot water supply wells. Nitrate in groundwater can come from natural sources such as soil, bedrock and organic material; however, the overwhelming loading of nitrate originates from anthropogenic sources, particularly agricultural practices and residential on-lot sewage treatment systems (a.k.a. “septic systems”). As residential subdivisions expand into previously undeveloped or agricultural areas, homeowners, developers, planners and township regulators are increasingly challenged with balancing sustained growth with a safe drinking water supply. Prevalent concerns are with high-density developments that utilize on-lot drinking water supply wells that draw from the same groundwater which is being impacted by the conventional nitrate-yielding on-lot septic systems. Unfortunately, the current solution implemented by most municipalities under the State’s (PA) sewage planning permit process is to require larger developable lot sizes, which only encourages sprawl.