There is a need to better quantify the wet deposition of nitrogen species not measured routinely by the NADP’s NTN and AIRMoN, including concentrations of nitrite ion and organic nitrogen. The Central Analytical Laboratory (CAL) measured nitrite ion and organic nitrogen in Atmospheric Integrated Research Monitoring Network (AIRMoN) samples collected in February – August, 2014. These nitrogen fractions were measured in addition to the existing nitrogen measurements which include ammonium and nitrate ions. This special study was part of a wider initiative sponsored by the U.S. EPA’s National Risk Management Research Laboratory to better quantify total dissolved nitrogen (TDN) in wet deposition samples. For the study period, the fraction of nitrite ion as total nitrogen ranged from 0 – 6.6%, with a median of 0.52%. The fraction of organic nitrogen ranged from 0 -  60%, with a median of 2.6%.  This poster presents an overview of the TDN quantification study, including an evaluation of quality assurance and quality control.