Chemical composition monitoring of surface waters in the development zone of the Amur-Yakutsk Mainline

Abstract

A short-term (2007–2017) and long-term (1965, 1967–2017) monitoring of chemical composition of surface waters in the development zone of the Amur-Yakutsk Mainline (AYAM) in the territory of southern Yakutia were conducted. According to the results of the short-term monitoring, the chemical composition of most of the rivers studied in southern Yakutia varied insignificantly. All recorded changes in the chemical composition of these waters were within the seasonal variation of their contents and values caused primarily by natural factors. In our opinion, significant anthropogenic and technogenic influence over the observation period was recorded only on 3 small rivers, including the Sylgylyr, Mundruchuch and the Lyutenga rivers. As the result of the long-term monitoring conducted in the coal and gold mining areas in the territory of southern Yakutia, we have identified significant changes in chemical composition of the Chulman and Aldan rivers, as the result of technogenic influence during the 30–40-year period of industrial development of southern Yakutia. At the same time, changes in all chemical indicators in waters of the Chulman and Aldan rivers do not exceed their maximum allowable values and meet the standards for drinking water supplies. Changes in chemical indicators in waters of the Chulman and Aldan rivers during the period of 2007–2017 indicate that technogenic stress on the Chulman River is gradually decreasing, and remains at the same level on the Aldan River.