The soil biological pollutions of ger horoolol area of Ulaanbaatar city was studied by 10 meter deep sampling, with laboratory analysis of E.Coli, Clostridum perfringens, Proteus, Salmonella pathogens. The maximum average biological pollution depth in the ger horoolol area soils of Ulaanbaatar city was found at 2.8 meter. This depth is nearly similar with pit latrine depths. Maximum depth highest pollution is at 3.5 meter with a 3,46 PLI at D1 location. The bacteria distribution lowest point is about 4-9 meter and depends on soil texture and density properties. Average lowest depth of soil bacteria pollution is 6.3 meter. Generally below 10 meters bacteriological pollution is not penetrating.
