Section 5(2)(a) in The Coking Coal Mines (Emergency Provisions) Act, 1971
(a)The Central Government may also appoint a person as the Custodian-General for exercising supervision and control over all the coking coal mines the management of which is taken over under this Act, and on such appointment, every Custodian, appointed under sub-section (1), shall act under the guidance, control and supervision of the Custodian-General.