donald trump big supporter u.s. oil gas coal industries promise get work quickly swear president unite state raise expectations sign slew executive order executive action maneuver could come quickly relate energy environment climate change trump republican promise kill democratic predecessor barack obama clean power plan require state cut carbon dioxide emissions power plant options simple others plan challenge 27 50 state court one option order justice department stop defend effectively give plaintiffs win trump could also seek voluntary remand ask court send rule back environmental protection agency review problem attorneys general state like new york california well environmental group would likely step gap defend rule another possibility would order epa enforce rule could open door lawsuits third option would trump administration try issue new regulation withdraw clean power plan even uphold court accord american energy alliance industry group help advise trump energy transition team move may fast one clean power plan finalize 2015 centerpiece obama broad climate change strategy water u.s. rule seek clarify waterways fall federal environmental protection mention repeatedly trump regulation hop overturn rule also challenge court legal experts say trump options similar one elegant ways overturn rule would voluntary remand legal vehicle would ask court return rule epa review would give trump administration ability kill revise rule could also draw lawsuits democratic attorneys general environmental group want rule preserve trump promise ask transcanada corp trp.to resubmit application build keystone xl pipeline project pipe canadian oil sand crude unite state reject obama administration years environmental lobby invitation resubmit could come quickly unclear whether transcanada would seek revive project give oil price far low company initially pursue trump may also seek issue order undo guidance issue last august white house council environmental quality require federal agencies quantify greenhouse gas emissions factor impact climate change evaluate project like pipelines council update decades-old national environmental policy act include greenhouse gas update trump could sign executive order approve dakota access pipeline north dakota order act secretary army approve project accord brigham mccown former head u.s. pipeline hazardous materials safety administration president george w. bush however move would highly unpopular among pipeline opponents camp construction site months leaders stand rock sioux tribe lead protest worry pipeline would threaten water quality vow challenge executive action pipeline own energy transfer partner lp etp.n one little-known tool use obama administration support regulations curb carbon emissions social cost carbon calculation make panel technical experts place dollar value public harm cause carbon dioxide emissions calculation use rule-making cost/benefit analysis current cost carbon put 36 per tonne rise 50 2030. american energy alliance believe trump could immediately order government agencies end use social cost carbon could help unravel number obama anti-carbon regulations trump could immediately lift department interior moratorium coal lease federal land department enact last year seek review program evaluate whether government adequately price value coal extract public land behalf taxpayer lift moratorium would improve industry access vast coal deposit remain powder river basin reverse obama recent move put federal acreage limit drill could complicate obama designate around 1.6 million acres federal land utah nevada monuments use tough-to-overturn law call antiquities act also permanently protect areas offshore arctic atlantic use another law legal experts say would challenge overturn obama administration finalize couple environmental regulations last weeks office likely quickly overturn include bureau land management methane rule stream protection act congressional leaders say would target rule congressional review act allow lawmakers use simple majority vote rescind regulation within 60 legislative days publication methane rule limit methane emissions energy installations federal land stream protection act protect waterways coal mine runoff rule affect agriculture industry could also fit category include u.s. department agriculture final rule regard production requirements organic livestock poultry establish minimum indoor outdoor space requirements chickens campaign white house trump say would pull unite state paris climate agreement within 100 days take office accord sign nearly 200 countries last year intend curb global warm slash emissions carbon dioxide greenhouse gas since november election trump soften stance slightly tell new york time would keep open mind deal nonetheless former new york businessman advise team swift options could take end u.s. participation accord include issue presidential order simply delete u.s. signature accord factbox quick action trump could take energy environment climate