 Globally, since 1940 till end 70s the production of coals Ombilin declined, and returned only tens of thousands of tons per year.Sawahlunto also faced a decline in coal production indicative of the decline in population to only 13,561 inhabitants in the 1980.With the increased number of facilities, a change in management and the application of new technology, the mining industry increased again since the beginning of the 80s.