Both happened on March 31st, not far from the capital Little Rock. There the controversial Mobile Exxon pipeline broke up and spilled "a river" of crude oil. Meanwhile the Arkansas Nuclear One power station is under "minor" emergency because an unclear accident that killed one worker, injured eight others and forced shutdown and venting of steam.
Source: Energy News (link 1, link 2, link 3).
Update: catastrophic consequences for wildlife, health risk for all → EneNews again.