such as trona to absorb the acid mist - and the addition of baghouses and booster fans to capture the resulting particulate. SCRs without baghouses are expected to cost about $600 million to construct and about $12 million per year to operate and maintain. SCRs with baghouses would cost about $1.1 billion to construct and about $20 million per year to operate and maintain. The SCRs by themselves would need about 15 MW to operate, requiring the burning of an additional 50,000 tons of coal per year and increasing CO2 emissions by 125,000 tons per year. If baghouses are also needed, the systems would need about 30 MW to operate, requiring an additional 100,000 tons of coal per year and increasing CO2 emissions by 250,000 tons per year. The operation would also consume some 40,000 pounds of anhydrous ammonia daily. The plant faced a number of hurdles to retrofitting SCRs in the allotted time. Before the plant's owners could invest in SCRs, they will have to resolve the site lease, rights-of-way for the railroad, transmission and water lines, and the coal supply agreement. One participant – LADWP – cannot invest in the improvements due to California law prohibiting long term investment in coal-fired power plants, and plans to sell its share in the plant by 2015. NV Energy announced it also intends to pull out of participation in the plant, planning to divest its interest by 2019. Extension of the plantsite lease with the Navajo Nation requires the approval of the Secretary of the Interior, who cannot approve it until environmental assessments required by the National Environmental Policy Act (NEPA) and the Endangered Species Act (ESA) are completed. The current lease expired in 2019 and the environmental assessments are expected to take about five years to complete. After the EPA issued a proposed BART rule it solicited input from stakeholders: the Department of the Interior, the Central Arizona Project, the Navajo Nation, the Gila River Indian Community, the Salt River Project, the Environmental Defense Fund, and Western Resources Advocates who as a technical working group negotiated a "Reasonable Progress Alternative to BART" which was submitted by the Department of the Interior to the EPA on July 26, 2013, for consideration in development of a final rule: The Parties shall submit this Agreement to EPA and request that EPA: adopt the Reasonable Progress Alternative to BART set forth in Appendix B