Yes, they are coffins. But most likely this is land leased by this company: www.vantageproducts.com

Wikileaks.com : 1000 US Soldiers Involved in ‘Terror Response’ training in Georgia between July 15 and August 8th, 2008 (the date the Georgian crisis commenced)

“How can I invade the middle of my own country?” barks the Georgian President, Saakashvili, at Wolf Blitzer on CNN. How about: “.. because it’s Russia?”