# Transmission of Heavy Metals in River Water and Self-Purification Capacity of Ile River
## 3 Research and Results
\begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multirow{2}{*}{**Season of Sampling**} & \multirow{2}{*}{**Sampling Site**} & **Cu** & **Zn** & **Pb** & **Cd** & **Co** & **Ni** \\ \cline{3-8}  & & \multicolumn{6}{c}{**mg/L**} \\ \hline  & Dobyn & 0.0131 & 0.0081 & 0.001 & 0.0072 & 0.0708 & 0.021 \\  & 164 km above HPP & 0.0001 & 0.0075 & 0.0099 & 0.0037 & 0.0756 & 0.0191 \\ Winter & 37 km below HPP & 0.0079 & 0.0062 & 0.0083 & 0.0037 & 0.0643 & 0.0285 \\  & Ushzharma & 0.0096 & 0.0073 & 0.0068 & 0.0025 & 0.0659 & 0.0191 \\  & Kokzhide & 0.0105 & 0.0071 & 0.0052 & 0.0041 & 0.0659 & 0.0154 \\ \hline  & Dobyn & 0.0062 & 0.0158 & 0.0078 & 0.0029 & 0.0643 & 0.0285 \\  & 164 km above HPP & 0.0079 & 0.0117 & 0.0042 & 0.0025 & 0.074 & 0.0416 \\ Spring & 37 km below HPP & 0.0053 & 0.01 & 0.0031 & 0.0021 & 0.0611 & 0.0416 \\  & Ushzharma & 0.0044 & 0.0104 & 0.0047 & 0.0029 & 0.0595 & 0.0191 \\  & Kokzhide & 0.0053 & 0.0121 & 0.0042 & 0.0002 & 0.0481 & 0.0341 \\ \hline  & Dobyn & 0.0079 & 0.0156 & 0.0094 & 0.0002 & 0.0416 & 0.0611 \\  & 164 km above HPP & 0.0018 & 0.0135 & 0.0099 & 0.0001 & 0.0434 & 0.0627 \\ Summer & 37 km below HPP & 0.0027 & 0.0121 & 0.0094 & 0.0000 & 0.0453 & 0.0724 \\  & Ushzharma & 0.0018 & 0.0121 & 0.0089 & 0.0000 & 0.021 & 0.0578 \\  & Kokzhide & 0.0053 & 0.011 & 0.0068 & 0.0001 & 0.0397 & 0.0675 \\ \hline  & Dobyn & 0.0125 & 0.0554 & 0.0062 & 0.0118 & 0.0756 & 0.0098 \\  & 164 km above HPP & 0.0119 & 0.0444 & 0.0052 & 0.0122 & 0.0708 & 0.0228 \\ Autumn & 37 km below HPP & 0.0112 & 0.0804 & 0.0062 & 0.0103 & 0.074 & 0.0098 \\  & Ushzharma & 0.0129 & 0.0823 & 0.0052 & 0.0114 & 0.0789 & 0.0079 \\  & Kokzhide & 0.0127 & 0.0548 & 0.0047 & 0.0114 & 0.0837 & 0.0154 \\ \hline  & MPCpx & 0.001 & 0.01 & 0.01 & 0.005 & 0.01 & 0.01 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Average heavy metal concentrations in Ile River water from October 2023 to September 2024 based on monthly measurements. of cobalt in this area was maximally high, exceeding the MPC\({}_{\rm f}\) up to 7.6. Insignificant exceedances were recorded for nickel (1.9 MPC\({}_{\rm f}\)) and lead (1 MPC\({}_{\rm f}\)), and zinc and cadmium were within the norm. Concentrations of heavy metals in water upward to the Kapshagai reservoir are given in Figure 3.  
In the transformation dynamics of the considered metals up to the reservoir, the increase from the level of the border post was noted in spring for copper, cobalt, and nickel; significant decreases in the concentration of these trace elements were recorded for copper in winter and summer. Characteristic regularities in fluctuations in temporal and spatial aspects (upward to the Kapshagai reservoir) of trace elements were not observed (Figures 2 and 3), obviously associated with the presence in the catchment area of the river basin sources of anthropogenic pollution by these compounds. Consequently, the growth of toxicant concentrations in transboundary runoff occurs mainly due to contributed pollutants and the inflow of metals from the Sharpn River to the point at 164 km. The role of denudation processes in the basin, obviously, has a subordinate position. Within the Kapshagai reservoir, samples were taken to identify the distribution of heavy metals in the water area during the spring period of 2024. The spatial distribution of heavy metals is given in Figures 4-6. Exceedances of the MPC\({}_{\rm f}\) for copper were observed from 1.8 times in the central part to 11.4 times in the dam zone of the reservoir during spring. The lowest copper MPC\({}_{\rm f}\) exceedances were observed in the area of the Yesik River confluence and in the central part of the reservoir. The highest MPC\({}_{\rm f}\) exceedances were recorded around the confluence of the Shengeldy River on the right side of the reservoir; on the left side of the Turgen, Baltabai, and Kaskelen rivers; and in the upstream zone due to return water inflow.