Inferno by Amelia Jade

Hollie Fowler has given up all hope of living a normal life when she returns to Drake’s Crossing. She lives for her job, operating a heavy duty borer, Big Betty. Hired to run a train line through the nearby mountains, she hopes to breathe life back into her hometown. What she doesn’t know, is she’s about to stumble upon an ancient beast, one who stirs up feelings she’s buried so deep even Big Betty couldn’t hope to reach them.
When dragon shifter Obsidian is awoken from a peaceful slumber, he’s determined to teach someone a lesson. So what if he’s been asleep for a few centuries too long, he’s a dragon, master of his own destiny. Until he sees her. Feisty and unafraid, this human holds his fate in her small but capable hands.
Sparks fly as Hollie and Obsidian clash. Drawn to each other, yet intensely independent, they must find a way to work together…because the dragon wasn’t the only thing buried under the mountain. Can Hollie work alongside the blunt dragon, from another time, and save the town from a dark danger that has awoken? Will she tame his brash, reckless nature? Or succumb to his unimaginable power, which makes her heart race, and her body pulse with an ancient need of its own.