3 Million Pounds of Nitrogen Removed and Counting at the Fairfax County NCPCP

Water Resource Reclamation Facilities (WRRFs) in the Chesapeake Bay watershed face regulatory pressures to treat to low effluent total nitrogen (TN) levels. Many WRRFs are now required to remove TN to below 3 mg/L, either on a mass load allocation or concentration basis, and some facilities are faced with even more stringent effluent limits. Conventional process configurations in the form of 4 or 5 stage BNR (Bardenpho) and/or tertiary denitrification filters are typical for treating to these stringent TN limits. The purpose of this paper is to document the performance of the Fairfax County Noman M Cole Jr. Pollution Control Plant (NCPCP), a 67-MGD WRRF that utilizes an alternate approach to Enhanced Nutrient Removal (ENR).