The aircraft clipped the snowplow on takeoff late Monday and crashed, bursting into flames and killing Total SA Chief Executive Christophe de Margerie and the three crew members on board.
Investigators have detained the snowplow driver, who they say was drinking on the job. His lawyer, however, denies this.
Channel One television on Wednesday showed footage of the driver, Vladimir Martynenko, being questioned. He said he didn't notice that he had strayed onto the runway and didn't hear the plane over the noise of the snowplow or see any lights.