Maryland has, by statute, permanently banned the practice of hydraulic fracturing, or fracking. There had been years of protests by landowners, health leaders, and environmentalists.
This makes Maryland the first state with proven gas reserves to use legislation to ban fracking. New York has banned the drilling process via executive order. Vermont has a statutory ban but the state has no frackable gas reserves at present.
Maryland only has gas reserves in the far Western end. This makes the ban less significant than it would be in states such as South Dakota, Texas, or even West Virginia but a ban is a ban no matter how small.