My lot has a lot of coal bits, broken glass bits, metal, mortar, concrete, brick pieces, etc. Structure is 126 years old, urban. Original heat was coal. I slowly get rid I f old soil and bring in compostables, and other enhancements. Any time we dig or it rains, we clean up small debris fields that surface. Sigh. We'll eventually get there but it does test the resolve at times. It is far from simple though. Small bits are well mixed into soil. Urban lots also often were used for the house waste as well. Luckily, I am not wanting to dig that deep!
