[1][2] Representing the former Soviet Union, Tkach won a silver medal in the women's double trap at the 1991 ISSF World Shooting Championships in Perth, Australia, with a total score of 121 clay pigeons.

[3] She also defeated Lithuania's Daina Gudzinevičiūtė by one point for the gold medal in the women's trap at the 2002 ISSF World Shooting Championships in Lahti, Finland, accumulating a score of 93 targets.

[3][4] Tkach is also a member of the shooting team for Dynamo Voronezh, and is coached and trained by her teammate and two-time Olympian Maxim Kosarev.

She scored a total of 81 clay pigeons 65 in the preliminary rounds and 16 in the final) in the women's trap by five points behind German shooter and Olympic silver medalist Susanne Kiermayer, finishing only in sixth place.

[5] The following day, Tkach placed sixteenth in the qualifying rounds of the women's double trap by three points behind Canada's Susan Nattrass, accumulating a score of 90 targets.