HOLE LOTTA FUN IN JAPAN

You've got to hand it to the Japanese for coming up with some of the most outlandish pursuits.  Today I read in the paper that Japan was hosting its National Hole Digging Competition.  Over 1,000 people took part in the competition which awarded prizes for the deepest hole, the most creative hole and for the most original costume being worn for digging.  First prize a golden shovel and around 100,000 YEN (about £820).  What I'd like to know is who gets to fill in the holes afterwards?