Indiana Code Title 10. Public Safety § 10-14-5-11

(a) This compact shall become effective immediately upon its enactment into law by any two (2) states.  Thereafter, this compact shall become effective as to any other state upon enactment by such state.

(b) Any party state may withdraw from this compact by enacting a statute repealing the same, but no such withdrawal shall take effect until thirty (30) days after the governor of the withdrawing state has given notice in writing of such withdrawal to the governors of all other party states.  Such action shall not relieve the withdrawing state from obligations assumed under this compact before the effective date of withdrawal.

(c) Duly authenticated copies of this compact and of such supplementary agreements as may be entered into shall, at the time of their approval, be deposited with each of the party states and with the Federal Emergency Management Agency and other appropriate agencies of the United States Government.