Peak coal the US has declined as mining shifts to coals of lower rank. Although the tonnage of coal mined in the United States reached its latest peak in 2008, the peak in terms of coal energy content occurred in 1998, at 598 Millions of metric tons of oil equivalent (Mtoe); by 2005 this had fallen to 576 Mtoe, or about 4% lower. Australia has substantial coal resources, mostly brown coal. It is responsible for almost 40% of global coal exports worldwide, and much of its current electricity is generated from coal-fired power stations. There are tentative plans to very slowly phase
Environmental impact of the coal industry This is due to the relaxation of pressure and fracturing of the strata during mining activity, which gives rise to safety concerns for the coal miners if not managed properly. The buildup of pressure in the strata can lead to explosions during (or after) the mining process if prevention methods, such as "methane draining", are not taken. In 2008 James E. Hansen and Pushker Kharecha published a peer-reviewed scientific study analyzing the effect of a coal phase-out on atmospheric CO levels. Their baseline mitigation scenario was a phaseout of global coal emissions by 2050. Under the "Business as Usual" scenario,