The United States is now the world's largest oil and gas producer.

That is in part because of what is happening in North Dakota where advances in fracking have unlocked crude oil in the Bakken shale formation in the western part of the state.

North Dakota is now producing more than a million barrels of oil a day. Ten years ago there were fewer than 200 oil-producing wells in the Bakken. Now there are more than 8,000.

The rapid pace of development has made North Dakota the state with the lowest unemployment rate in the nation, but the boom has brought with it a serious problem: It has the highest worker fatality rate in the nation.

Fault Lines spent six months investigating safety risks in North Dakota's oil fields and uncovered a dark side to the boom - the human cost. Why are so many dying and who should be held responsible?

Source: Al Jazeera