Fracking doesn’t always go to great depths
Shallow wells raise possibility of drinking water contamination
![U.S. oil and gas wells](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2015/07/bm_fracking_free.jpg?fit=860%2C460&ssl=1)
GOING DEEP? A surprising number of U.S. oil and gas wells, similar to this one, are hydraulically fractured at shallow depths, a new study finds.
Lilsqueaky/Wikimedia Commons (CC BY-SA 3.0)