Ust-TarkaUst-Tarka is a rural locality and the administrative center of Ust-Tarksky District, Novosibirsk Oblast, Russia. Population:GeographyUst-Tarka lies on the bank of the Om River by the confluence of the Tarka River, west of Novosibirsk and north of Tatarsk, where the Trans-Siberian Railway station is located.