alt Hacker NewsItems degrade but what often remains is imprint of it in surrounding material, that over time becomes rock. We dumped enough shit all around us that is too smooth/right angled/whatever to look like natural product. If anybody digs enough, they will find enough evidence, direct or indirect.
That is, till all currently-up tectonic plates submerge for melting. But since they don't move by same speed, some of it will probably remain around till sun inflates and scorches surface or even absorbs Earth. That will be probably it, melted surface will hide or destroy all of it. But thats what, 1 billion years in future?
It all depends on how long. Eventually all the current surface will be sucked under tectonic plates and come out after passing some time in the mantle. We can plan for that by planting evidence in places that aren’t likely to go through that, but, give enough time, most of the crust will be recycled.