Mass. Gen. Laws ch. 21D § 13
A siting agreement may be established by the signature of the chief executive officer of a host community who has been directed by a majority vote of the local assessment committee of said host community to sign and the signature of any officer of the developer expressly authorized by the developer to sign said agreement, or by arbitration pursuant to section fifteen.
All state agencies shall endeavor to assist in facilitating negotiations between local assessment committees, the chief executive officer of abutting communities, and the developer. The council shall be available during such negotiations to assist in the exchange of information and to encourage and facilitate access to opinions, reports, documents and other materials relevant to the siting agreement including, but not limited to, all public records produced as part of the hazardous waste facility siting process established by this chapter.
Mass. Gen. Laws ch. 21D, § 13