 According to the 2010 census , the county has a total area of 486 @.@ 52 square miles ( 1 @,@ 260 @.@ 1 km2 ) , of which 484 @.@ 52 square miles ( 1 @,@ 254 @.@ 9 km2 ) ( or 99 @.@ 59 % ) is land and 2 @.@ 00 square miles ( 5 @.@ 2 km2 ) ( or 0 @.@ 41 % ) is water . 
