PART 504 — EXISTING POWERPLANTS [ 10 CFR 504 ]PART504 — EXISTING POWERPLANTS [ 10 CFR 504 ]Table of Contents§ 504.2 — Purpose and scope.[ Last FR update: 11/10/1982 ]§§ 504.3-504.4 — [Reserved]§ 504.5 — Prohibitions by order (certifyingpowerplants under section 301 of FUA, as amended).[ Last FR update: 04/21/1982 ]§ 504.6 — Prohibitions by order(case-by-case).[ Last FR update:11/10/1982 ]§ 504.7 — Prohibition against excessive useof petroleum or natural gas in mixtures—electing powerplants.[ Last FR update: 11/10/1982 ]§ 504.8 — Prohibitions against excessiveuse of petroleum or natural gas in mixtures—certifyingpowerplants.[ Last FR update:04/21/1982 ]§ 504.9 — Environmental requirements forcertifying powerplants.[ Last FRupdate: 04/21/1982 ]Appendix I to Part 504 — Procedures for the Computation of the Real Cost of Capital[ Last FR update: 12/07/1981 ]Appendix II to Part 504— Fuel Price Computation[ Last FR update: 12/22/1989 ]Authority: Depar...