Increasingly stringent restrictions on mercury concentrations in wastewater discharge may be problematic for aging research laboratory facilities. Relatively high levels of mercury compounds may exist and concentrate deep in the plumbing system and their sediments, resulting in elevated wastewater concentrations. This study was conducted to assess total mercury levels in an aging laboratory building wastewater system. Wastewater outflow, sink trap water, and pipe sediment samples were collected from the building. The Jerome 431 Mercury Vapor Analyzer was assessed as a tool for screening lab sink trap drains for mercury deposition. Results revealed that the three day average for mercury discharge from this single structure, if not diluted by other waters, would be above the local total release parameters to the wastewater treatment plant. The sink traps did not contain a majority of the mercury; however, the pipe sediment and outflow samples revealed consistently elevated concentrations.