prompt: In what year were the Mercury and Air Toxics Standards adopted? 
  
  The proposed rule will support and strengthen EPA's Mercury and Air Toxics Standards, which have delivered a 90% reduction in mercury emissions from power plants since they were adopted in 2012 under President Barack Obama, EPA Administrator Michael Regan said.
  
  "By leveraging proven, emissions-reduction measures available at reasonable costs and encouraging new, advanced control technologies, we can reduce hazardous pollution from coal-fired power plants — protecting our planet and improving public health for all," Regan said in a statement.
chosen.role: system
chosen.content: A chat.
chosen.role: user
chosen.content: In what year were the Mercury and Air Toxics Standards adopted? 
  
  The proposed rule will support and strengthen EPA's Mercury and Air Toxics Standards, which have delivered a 90% reduction in mercury emissions from power plants since they were adopted in 2012 under President Barack Obama, EPA Administrator Michael Regan said.
  
  "By leveraging proven, emissions-reduction measures available at reasonable costs and encouraging new, advanced control technologies, we can reduce hazardous pollution from coal-fired power plants — protecting our planet and improving public health for all," Regan said in a statement.
chosen.role: assistant
chosen.content: 2012
rejected.role: system
rejected.content: A chat.
rejected.role: user
rejected.content: In what year were the Mercury and Air Toxics Standards adopted? 
  
  The proposed rule will support and strengthen EPA's Mercury and Air Toxics Standards, which have delivered a 90% reduction in mercury emissions from power plants since they were adopted in 2012 under President Barack Obama, EPA Administrator Michael Regan said.
  
  "By leveraging proven, emissions-reduction measures available at reasonable costs and encouraging new, advanced control technologies, we can reduce hazardous pollution from coal-fired power plants — protecting our planet and improving public health for all," Regan said in a statement.
rejected.role: assistant