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The main objective of ThermoMap project was to develop a methodology for estimating the thermal conductivity and heat capacity in the first 10 m of the ground, in order to identify areas favourable for installation of ground heat source pumps. Based on best available data regarding climate, soil type, soil texture, geology and water table depth, maps of the thermal parameters were computed in test areas from partner countries. Three depth layers were investigated: 0-3, 3-6 and 6-10 m, each one characteristic for different types of ground source heat pumps. In order to check the computed values, samples were collected in test areas and measured in the laboratory. This paper presents the results of the validation performed for Constanta county test area (Romania). Samples of soil and Quaternary formations collected in the Danube terraces and the Black Sea high shores were analyzed in the laboratory for determining the bulk density, soil texture, thermal conductivity and heat capacity. The measurements were performed on samples simulating the three possible system conditions: unsaturated (arid or humid) and saturated conditions. The values determined by laboratory measurements were interpolated in order to obtain the appropriate thermal conductivity values for the defined bulk density values used by ThermoMap for each depth layer. The comparison between ThermoMap computed data and the laboratory measurements of thermal conductivity showed that out of three samples, at least two are within the specified error range of ±25 %. The best fit occurs for layer 3-6 m, whose assigned density is closer to the mean of measured bulk density values. [ABSTRACT FROM AUTHOR]