Is it possible to flare off the gas?
I would think so. Here in the U.S. we punch wells down into the landfill and pump the contaminated air to filter and such. Some places use it to run generators. But just a flare would at least get rid of the contaminated air. I imagine there are residues that might not be so great, but nothing like the hydrogen sulphide. Although I’m not sure how affects the body. I know if it gets too high it can kill you quickly - I think it replaces the O2 in your lungs so you sufficate? On oil rigs they have the H2S alarm.
More than likely. If theres that much its gotta have enough methane to burn, even if it didnt though you could run it through and engine with supplemental fuel.
Get this, at a old closed landfill in [undisclosed N. CA location] it was just pumping out of monitoring wells there. Engineer tells me they could run the whole facility off 4 cyl generators digesting it but Air Resources Board says no, it might emit some NOx...