Memorandum signed on Bazhenov field between Russia's second largest oil producer and the French giant.
TNK-BP, a Russian-British company, is under fire concerning 784 environmental accidents reported in 2011, compared with 20 by rival Lukoil.
Floodwater from Ob River is black from spill as emergency workers flight to limit damage.
Three crashes in four days with total toll of 16.
A renaissance of one of Siberia's first outposts as the Far North becomes the new economic frontier.