Bone Pit (The Gina Mazzio Series Book 3)

RN Gina Mazzio is not a wimp, but after nearly being murdered twice in the recent past, she needs a time out. Needs to get away from San Francisco and Ridgewood Hospital.
In this third Gina Mazzio, RN series of medical thrillers, Gina and fianc Harry Lucke sign up for a Travel Nurse assignment at a small Nevada facility involved in clinical drug trials, somewhere in the middle of nowhere. On their first day, driving down a long, creepy private road, ominous sentry-like boulders rise up to block out the sun. When they finally arrive, Gina's "warning" eye starts to twitch when she sees iron bars across all the second-story windows.
What kind of place is this, what are they really getting into?