White Sea–Baltic Canal had plans to carry 800,000 tonnes of fuel oil over the canal during 2003, and to increase the volume to in 2004. The fuel was transferred from Volgotanker river tankers to Latvian seagoing tankers at a floating transfer station near the Osinki Island in the Onega Bay of the White Sea, north-east of the port of Onega. Transfer operations began on 24 June 2003. But on 1 September 2003 a low-speed collision between Volgotanker's "Nefterudovoz-57M" and the Latvian "Zoja-I" during a transfer caused a crack in the "Nefterudovoz's" hull, with a subsequent oil spillage. Various estimates of the extent of
Onega stepanovi placed in phylum Proarticulata, as the segments in recently discovered, exceptionally well-preserved fossils display the glide, or "staggered", symmetry characteristic of the majority of proarticulatans. Imprints of "Onega stepanovi" have been found in the Verkhovka and Zimnie Gory Formations of the Ediacaran (Vendian) rocks of the Arkhangelsk Region, Russia. All the fossil specimens are negative imprints on the bases of fine-grained sandstone beds with the "elephant skin" and tubercle texture diagnostic of microbial mats. The same bedding planes contain various other Ediacaran species: "Cyclomedusa", "Ediacaria", palaeopascichnids, "Eoporpita", "Yorgia", "Andiva", "Archaeaspinus", "Vendia", "Dickinsonia", "Anfesta", "Albumares", "Tribrachidium", "Kimberella", "Parvancorina", "Charniodiscus" and others.