Removal of PPCPs within surface application wastewater systems

Pharmaceuticals and Personal Care Products (PPCPs) are used worldwide and enter the environment via wastewater treatment system effluent discharges. With increasing concern in water reuse, attention is turning to the wastewater stream. One of the most common reuse procedures is land application of wastewater, which follows a wastewater treatment plant or an onsite wastewater treatment system (OWTS). It is not known how well conventional on-site wastewater disposal practices function in removing PPCPs prior to percolation into ground water. The objective of this study is to investigate the removal of PPCPs from onsite wastewater systems where the final discharge is on the soil suriace and to compare the capacity of three land application structures, vegetated lawn, bare land and underground leach field, in PPCP removal. To accomplish the objectives, three different types of undisturbed soil columns: grass-covered, plastic-covered, and open columns, each with three replications, that were irrigated daily with synthetic wastewater. Leachate samples were collected and analyzed for pharmaceuticals concentrations using HPLC-MS analytical devices. The removal efficiencies were more than 95% for all compounds in all systems. However, the grass columns showed more than 73% increase (p<0.05) in the removal capacity in compare with the covered columns. The open columns showed more than 45% increase (p<0.05) in the removal capacity comparing to the covered columns. The results of this study would suggest that vegetated lawns have higher capacity in PPCP removal rather than bare land and underground leach fields.