Pollution of Tyya River and Lake Baikal littoral surface waters in the zone of influence of waste water from the Severobaikalsk Town wastewater treatment facilities: assessment by geochemical method

Original Paper

Abstract

The composition of chemical elements from the Tyya River, wastewater from water treatment facilities (WTF) in Severobaikalsk town and from surface waters of Lake Baikal littoral in the zone of influence of polluted riverine waters were studied using the ICP-MS method. It is found out that water fraction of WTF waste waters from Severobaikalsk town into total riverine drainage of the Tyya R. is very low (~0.04%) due to a great water content of the river itself. However, geochemical contributions by several elements are rather considerable (Cl – 29%, P – 7,3%, Na – 4,2%, Zn – 2,7%). The influence of the Tyya R. polluted waters onto the adjacent littoral of Lake Baikal is limited by the sector of 200-300 m from water edge in frontal direction (water fractions of riverine waters are 26-4%), however, in the coastal zone it extends out of the delta. Among the studied objects, maximal geochemical effect of WTF waste waters from Severobaikalsk town concerns the Tyya R. and coastal water in Lake Baikal littoral in 550 m rightward from the mouth of main duct, where water fraction of riverine waters is maximal (86%). In these objects, Summary Geochemical Fraction (SGCF) of waste waters calculated by 41 informative chemical elements was 53 and 35%, respectively. At other stations in Lake Baikal littoral in the coastal zone, SGCF is not great – 2.8-7.5%. In the sector of 200-300 m from water edge, SGCF is comparable with the coastal zone – 1.5-8.1%. In the sectors of 500-600 and 800 m from the water edge, SGCF is minimal – 0.07-0.21%. In WTF waste waters from Severobaikalsk town, exceeding of regulations by P (69 MAC), Mn (6 MAC), Zn (3.4 MAC), Cu (2.1 MAC), Mo (1.7 MAC) and V (1.3 MAC) was detected.