In addition to the requirements of § 6429 of this title, the Authority is directed to undertake a feasibility analysis of establishing separate material and energy recovery facilities to Kent County and Sussex County independently. Such analysis shall include consideration of the availability of solid waste material, the market for recovered materials and energy, the effect of other recycling and waste reduction measures, general project economics and environmental impacts. The Authority shall not be entitled to proceed with a material and energy recovery facility under the provisions of § 6429 of this title until such time that the feasibility study required hereunder is filed with the Governor, the President Pro Tempore of the Senate, and the Speaker of the House of Representatives. Such feasibility analysis shall be completed and filed no later than January 15, 1991.