sentences:  It was also announced that 60 coal mines in the surrounding area were to be inspected for similar violations soon after the disaster, and that the entirety of the nation's mines would be inspected during the coming weeks.Preliminary findings from the Ulyanovskaya investigation found that safety equipment had been tampered with deliberately to decrease the readings of methane levels in the mine.According to Governor Tulayev, this was done "consciously in order to increase coal production".