Nitrate Reduction by in-situ Bio-Denitrification in Groundwater Available to Purchase

This paper reports the results of a preliminary investigation designed to assess the potential of using in-situ bio-denitrification to reduce nitrate concentration in contaminated groundwater. The main objectives were to identify problems that may be expected to arise in in-situ groundwater denitrification; study chemical, physical and biological factors controlling subsurface bio-denitrification; and evaluate the effects of biological reactions on the resulting groundwater quality. Results confirm the technical feasibility of using in-situ nitrate removal. The relative stability of denitrification performance was observed at high carbon concentration (C:N=1.5), providing a maximum nitrate removal efficiency of 80%. The proliferation of biomass profoundly affected the potential interactions of contaminants and microorganism in subsurface region. Relatively high solids accumulation in the vicinity of the wells and their nearby aquifer matrix caused severe clogging problems and created high head-loss in the aquifer system.