N.H. Rev. Stat. Ann. § 147:46

Nothing contained in this subdivision shall relieve communities of obligations, existing under other provisions of law, to abate open dumps or nuisances, or to establish sanitary landfills, and nothing herein shall impose upon any municipality in this state a financial burden in excess of that required under the law as it existed prior to the enactment of this provision, except for requirements mandated by the general court in legislation passed to implement a state plan.