He doesn't say anything as she works, but he does watch her. Because she believes she can do, she can do it. But there are hundreds of thousands of dead to dispose of.

It takes a long time for one woman.

At first it also doesn't seem to do anything really. There's so many corpses that one or two or a dozen or a hundred or a thousand make no dent int the piles of the dead.

Make no dent in the atmosphere.

But, slowly, very slowly, there begins to be a shift. And as she finally finishes about halfway, the light seems to get better, less gloomy.