With the help of the GEORADAR-EXPERT software system an assessment was made of the consequences of a breakthrough in the capacity of a septic tank located in permafrost soils (Mirny, Yakutia). As a result of the penetration of warm sewage into the frozen ground, there was a threat to the integrity of the foundations of nearby buildings. The purpose of the GPR survey is to determine the thawing zones of the ground. The figure below shows the layout of the septic tank and GPR profiles. The blue arrow shows the position of the GPR profile, the result of the analysis of the backscatter field BSEF which is shown in this publication.

Below is the result of constructing a section of the real part of the complex relative permittivity along the GPR profile intersecting the location of the septic tank. On the section, soils with temperatures below zero degrees Celsius are displayed in blue shades. The thawed soil is represented by a yellow - red color scheme, and the more moist the soil, the more saturated the red color. The section shows that the greatest moisture is at the location of the septic tank (elevation 27 m) and the thawing depth reaches 5 meters.