According to a French documentary television film "Tank on the Moon" by Jean Afanassieff, the Lunokhod design returned to the limelight 15 years later due to the Chernobyl nuclear power plant disaster on April 26, 1986. The East German-built remote controlled bulldozers available to Soviet civil defense troops weighed dozens of tons too heavy to operate on the remaining parts of the partially collapsed reactor building roof. Human labourers could not be employed to shovel debris since work shifts were limited to 90-second intervals due to intense ionizing radiation.