## 2 Material and Methods
### Laboratory Research  
#### 2.3.1 Radiation Research  
The activities of natural and artificial radionuclides were measured in soil samples. For research, a gamma-spectrometry machine was used. One of the main elements of the device is the spectrometric track consisting of a multichannel analyzer (MCA). The analyzer works with a germanium semiconductor detector (high-purity germanium (HPGe) with an efficiency of 25% and a resolution of 1.8 keV for the second cobalt \({}^{60}\)Co line (energy of 1332 [keV]). The input voltage at the detector was 4000 V. The spectrometer was calibrated for energy by acquiring a spectrum from radioactive standard sources of known energies \begin{table}
\begin{tabular}{l l l l} \hline
**Site** & **Name of Point** & **Attitude** & **Longitude** \\ \hline
16 & Uroczysko Laski & 51\({}^{\circ}\)21\({}^{\prime}\)26\({}^{\prime\prime}\) & 23\({}^{\circ}\)15\({}^{\prime}\)36\({}^{\prime\prime}\) \\ \hline
17 & Urszulin Prehod & 51\({}^{\circ}\)27\({}^{\prime}\)45\({}^{\prime\prime}\) & 23\({}^{\circ}\)7\({}^{\prime}\)24\({}^{\prime\prime}\) \\ \hline
18 & Wielki Lan & 51\({}^{\circ}\)28\({}^{\prime}\)56\({}^{\prime\prime}\) & 23\({}^{\circ}\)11\({}^{\prime}\)36\({}^{\prime\prime}\) \\ \hline
19 & Wola Wereszczynska & 51\({}^{\circ}\)26\({}^{\prime}\)7\({}^{\prime\prime}\) & 23\({}^{\circ}\)6\({}^{\prime}\)8\({}^{\prime\prime}\) \\ \hline
20 & Wolka Wytycka & 51\({}^{\circ}\)26\({}^{\prime}\)39\({}^{\prime\prime}\) & 23\({}^{\circ}\)12\({}^{\prime}\)46\({}^{\prime\prime}\) \\ \hline
21 & Zereminfska & 51\({}^{\circ}\)28\({}^{\prime}\)52\({}^{\prime\prime}\) & 23\({}^{\circ}\)9\({}^{\prime}\)15\({}^{\prime\prime}\) \\ \hline \end{tabular}
\end{table} 
Table 1: _Cont._like cobalt \({}^{60}\)Co (1332 keV, 1773 keV) and cesium \({}^{137}\)Cs (662 keV). A soil sample was placed on the HPGe detector, so the measurement could begin. The measurement time for a single sample was 80,000 [s], that is about 22.5 h.  
After the series of measurements was completed, the results of the tests were statistically analyzed. The results of the activity of the natural potassium \({}^{40}\)K, radium \({}^{226}\)Ra, and actinium \({}^{228}\)Ac radionuclides and of artificial origin--cesium \({}^{137}\)Cs in the soil were converted into a mass unit and the radionuclide concentrations were determined. The activity concentrations of actinium \({}^{228}\)Ac, potassium \({}^{40}\)K, radium \({}^{226}\)Ra and cesium \({}^{137}\)Cs were determined using a single peaks of 583.19 keV (intensity 84.5%), 1461 keV (intensity 10.72%), 186 keV (intensity 96.1%), and 661.7 keV (intensity 90.1%), respectively. The following equation was used to calculate activity concentrations of radionuclides in Bqkg\({}^{-1}\)[11; 37]:  
\[A_{Ei}=\frac{C_{Ei}}{C_{eff}\cdot\gamma\cdot m\cdot t}\ \left[\frac{Bq}{kg}\right] \tag{1}\]  
where:  
C\({}_{\rm EI}\)--total count of a peak at energy \(E\),  
C\({}_{eff}\)--detection efficiency at energy \(E\),  
\(\gamma\)--the percentage of gamma emission probability of the radionuclide \(i\) for a transition at energy \(E\),  
\(m\)--mass of measured samples (kg),  
\(t\)--counting time (s). The content of anthropogenic radionuclides in the soil is often provided on the surface area in kBqm\({}^{-2}\). Such a quantity is called a deposition. The deposition of cesium \({}^{137}\)Cs is described by the following equation:  
\[Dep\ \left[\frac{kBq}{m^{2}}\right]=\frac{A_{Ei}\left[\frac{Bq}{kg}\right]}{100 0}\times\frac{M[kg]}{7\times P\ [m^{2}]}=\frac{S\times m}{1750\times\pi\times D^{2}}\ \left[\frac{kBq}{m^{2}}\right] \tag{2}\]  
where:  
\(Dep\)--surface concentration in kBq/m\({}^{2}\) (deposition),  
\(P=\frac{\pi\times D^{2}}{4}\)--is a field the surface from which the soil is taken using a die with a diameter of \(D\). In the study, the absorbed dose rate and the annual effective dose rate have been calculated.