The county has a total area of 665 square miles ( 1,723 kmÂ ) . Out of this , 654 square miles ( 1,694 kmÂ ) is land and 11 square miles ( 30 kmÂ ) ( 1.72 % ) is water . According to the U.S. Census Bureau , the county has a total area of 665 square miles ( 1,723 kmÂ ) , of which 654 square miles ( 1,694 kmÂ ) is land and 11 square miles ( 30 kmÂ ) ( 1.72 % ) is water .