If you look through the site link below at Maryland, West Virginia, and Virginia, there are some groups listed that you might like. Some of these groups are in DC suburbs. Some are a little farther away. http://www.buddhanet.info/wbd/country.php?country_id=2
This is a forest tradition a few hours away from you in West Virginia. To get there, you would need to drive.http://www.bhavanasociety.org/about/
I hope you find something to your liking. To start a group, i would suggest advertising in health food stores, co-ops, new age bookstores, and on college campuses. Good luck!