There are thousands of dirty old drill sites in Colorado. The state gave oil firms a $1bn pass

When Christiaan van Woudenberg moved to Erie, Colorado , in 2007, he never imagined he would become an anti-fracking activist. He simply thought he was buying his dream home – a four-bedroom with a panoramic mountain view, 30 minutes north of downtown Denver . Then, in 2014, the drilling started. Oil and gas rigs sprang up, some just 800ft (240m) from his bedroom window. The dream turned to nightmare: loud noises rumbled all night long, and the air stank like exhaust. …