RISK ASSESSMENT OF SEWAGE FROM LEAKY SEWERS IN URBAN UNDERGROUND FOR SOIL AND GROUNDWATER

摘要

Trickling of sewage from leaky sewers was investigated in sand columns to simulate worst conditions for biological degradation, due to a short hydraulic retention. Experiments covered trickling of dilute and concentrated sewage, the soluble and particulate portion, changes of trickling rates with periodical colmation and the elimination of pharmaceuticals and of different bacterial groups during passage of sewage through the sand. A considerable part of the soluble organic material is non-degradable and many bacteria, including feacal bacteria are reaching the groundwater and creating a risc for health of humans, if the polluted groundwater is the source of potable water.