Section 15. For a period of three years from the effective date of this chapter, the department shall study the necessity and desirability of rate regulation, and thereafter it may, upon its own motion or upon request of any issuing authority or licensee, after due hearing and investigation, fix and establish, for each community antenna television system in the commonwealth, a fair and reasonable rate of return from subscription rates charged to subscribers, said rates to be adequate, just, reasonable and non-discriminatory. Notwithstanding any other provision of this paragraph, the department may, after due hearing and investigation, suspend regulation of rates and charges in any cable television system upon a finding that adequate competitive alternatives exist to the provision of services offered by cable television systems. In the event of such a suspension, the department shall, by oversight and surveillance, review periodically any facts or standards employed in determining the presence of said competition.

The department shall cause notice of the time and place of every such hearing to be published in at least one newspaper of general circulation in the municipality or service area affected. Such notice and schedule shall be in such form as the department may deem expedient.

The department may make, and, at any time, alter or amend, reasonable rules and regulations to facilitate the operation of this section and enforce the application of the rates fixed and established by them, may conduct hearings and investigations under this section, and may at any time require any company to file with them such data, statistics, schedules, or information as they may deem proper or necessary to enable them to fix and establish or secure and maintain fair and reasonable rates. They may issue such orders as they find proper, expedient or necessary to enforce and administer the provisions of this section, to secure compliance with any rules or regulations made thereunder, and to enforce adherence to the rates fixed and established by them. The superior court for the county of Suffolk shall have jurisdiction in equity upon the petition of the department and after a summary hearing, to enforce all lawful orders of the department. Memoranda of all actions, orders, findings, and decisions of the department shall be signed by them and filed in their office as public records open to public inspection.