How do I stop my dad from digging through trash?

My dad is a hoarder and pulls broken crud out of the trash. He digs out stiff like broken tiles and dishes, empty pill bottles, etc. He's not recycling. He just piles it into the garage or basement. He even pulls my dirty underwear out and packs them into the already over-stuffed garage. This is really creeping me out. How do I stop him?