In the afternoon of July 20, a blast resounded through a tunnel being constructed in Sikkim’s Namchi district. The explosion took place in the head-race tunnel of the 500-MW Teesta VI hydropower project being constructed by NHPC, a public enterprise. Because of these constraints, only about 44% of the head race tunnel work has been completed. The NHPC safety document notes that “The explosibility of methane gas is between 5 to 15 percent” and that the “percentage of Methane required for maximum explosive violence is 10 percent”. Construction work during rainy seasonA notification issued in May by the Namchi district collector’s office pointed to other safety risks that projects like Teesta VI faced.