These unique root cellar plans show you how to build a root cellar for food storage by adapting a new concrete septic tank. Read more: http://www.motherearthnews.com/diy/root-cellar-plans-zm0z14amzreb.aspx#ixzz2wQ9IUSsA
Root Cellar - the author said it cost about $1,000 for this 8x8 foot cellar: concrete blocks were $1 each at the time, and he used about 320. About $500 for concrete and mortar, and the remainder for rebar, wood, etc. He contacted a local gravedigger to use a backhoe to dig out the space for the cellar.