An investigation into the performance of septic tank soak-pit systems and alternative infiltration systems in low permeability subsoils in Ireland

Abstract

In Ireland, domestic wastewater from oyer one-third of the population, or approximately 500,000 dwellings is discharged to on-site treatment systems. With oyer 25% of our water supplies provided by groundwater, the prevention of nutrient and pathogen migration to our water bodies is of paramount importance. Up until recently, research has focused on the threat to groundwater due to effluent application to relatively permeable subsoils. Ireland's Environmental Protection Agency (EPA) published a Code of Practice for Single Houses in 2009 which outlines the subsoil conditions that will provide an acceptable level of treatment for on-site wastewater in order to protect our water sources from effluent contamination. In more recent times however, the risk to both surface water and groundwater quality from effluent run-off as a result of inadequate percolation has been raised.