I'm making a garden and i have some Styrofoam chunks from a TV I bought. I need the garden raise off the ground so I built a retaining wall and I was going to fill it with dirt, can I bury the styrofoam to save money and effort on filling it completely with dirt? I know styrofoam is a horrible product environmentally, so I was wondering if this would be a safe way to recycle it. I already use styrofoam cups as pots from my plants. Is there any chemical in the styrofoam i should be worried about or a problem with it that i didn't think of? I planned on burying it deep so it wouldn't float to the surface.