The department is hereby empowered to investigate the conditions and methods relating to the disposal of sewage in any municipality, as set forth in N.H. Rev. Stat. § 486:1, and to require the installation of public sewers, as defined in N.H. Rev. Stat. § 147:8, whenever such investigation demonstrates that individual sewage disposal systems are inadequate or incapable of protecting the health and welfare of the citizens of the affected municipality or preventing pollution of the surface waters of the state, as defined in RSA 485-A. Before issuing an order requiring the installation of public sewer facilities, the department shall notify the municipality of its findings and shall give the municipality an opportunity to be heard. After such hearing if it shall be determined that said facilities are necessary, the municipality shall be so notified in writing and the requirements so ordered shall be effected pursuant to N.H. Rev. Stat. § 38:25 within a reasonable time to be fixed by the department. If any municipality whose duty it is to act shall fail or refuse for a period of 10 days after the expiration of the time fixed by said order, or, in the case of appeal for a period of 10 days after final judgment shall have been entered, to obey the same or in good faith to begin to make the installation as ordered, such municipality so failing shall be fined not more than $1,000 for each day of failure to comply with the order of the department. Said fine shall be paid to the state and may be recovered in an action of debt brought by the attorney general in the name of the state treasurer.