Regular monitoring of the quality of the Paka River in
the influence area of the Šoštanj Thermal Power Plant has been carried out
since 1990 and comprises monitoring of the hinterland, biological analyses of
embankments and the river bottom (phytobenthos and macrozoobenthos) and
physical-chemical analyses. Samples are taken four times a year in different
seasons and in periods of low flow of the Paka River in Pesje, in Preloge, in
front of TEŠ, behind TEŠ and in Skorno. The monitoring includes all elements
prescribed by applicable legislation. The quality of the Paka River has
improved in recent years, predominantly the result of construction and
modernisation of the sewage system in the Šaleška dolina Valley, the extension
of the Central Treatment Plant for sewage waters with biological purification
and changed method of transport of ashes and gypsum from TEŠ to the
rehabilitation area of the collapsed formation between the Velenje and Družmir
lakes.