Vt. Stat. tit. 10 § 2502
This agreement shall become operative immediately as to those states ratifying it whenever any two or more of the states of Maine, New Hampshire, Vermont, Rhode Island, Connecticut, New York, and the Commonwealth of Massachusetts have ratified it and the Congress has given its consent. Any state not mentioned in this article which is contiguous with any member state may become a party to this compact. Subject to the consent of the Congress of the United States, any province of the Dominion of Canada which is contiguous with any member state may become a party to this compact by taking such action as its laws and the laws of the Dominion of Canada may prescribe for ratification. In this event, the term "state" in this compact shall include within its meaning the term "province" and the procedures prescribed shall be applied in the instance of such provinces, in accordance with the forms and practices of the Canadian government.
10 V.S.A. § 2502