The paper presents the variation of tritium activity concentration in the environment of Experimental Pilot Plant for Tritium and Deuterium Separation (PESTD) over 6 years of observations. The tritium level was established in surface water, air, precipitation, home-grown vegetable, meat and milk. The yearly average tritium concentrations in air were slightly higher than values for the preoperational monitoring program. The values of tritium concentration in surface water and fresh products used for human consumption did not exceed 3 Bq/kg fresh weight. Nuclear activity of PESTD did not have any impact on the environment so far.