MSNBC has a good story about the closure of Fort Reno Park in Washington, D.C. A video of the local news report can be viewed by clicking on the link titled 'Watch The Report'
http://video.nbc4.com/player/?id=251860 . Several other parks in the area have also been tested for arsenic, however the decision was made not to close them. It's still unclear how long Fort Reno may remain closed.
http://www.msnbc.msn.com/id/24656659/