County-owned solid waste facilities shall not be subject to any tax or excise imposed by any city or town. Cities or towns may charge counties to mitigate impacts directly attributable to the solid waste facility: PROVIDED, That any city or town establishes that such charges are reasonably necessary to mitigate such impacts and that revenue generated from such charges is expended only to mitigate such impacts. Impacts resulting from commercial and residential solid waste collection within any city or town shall not be considered to be directly attributable to the solid waste facility. In the event that no agreement can be reached between the city or town and the county following a reasonable period of good faith negotiations, including mediation where appropriate, the matter shall be resolved by a board of arbitrators, to be convened at the request of either party, such board of arbitrators to consist of a representative from the city or town involved, a representative of the county, and a third representative to be appointed by the other two representatives. If no agreement can be reached with regard to said third representative, the third representative shall be appointed by a judge of the superior court of the county of the jurisdiction owning the solid waste facility. The determination by the board of arbitrators of the sum to be paid by the county shall be binding on all parties. Each party shall pay the costs of their individual representatives on the board of arbitrators and they shall pay one-half of the cost of the third representative.