You are asking for a recommendation so I will answer this with what I would do.
First thing to try, calling your local trash hauler or your county or whoever regulates trash hauling services and asking them what materials they would take in your regular trash and what is recyclable.
Then I would dig a hole deep enough to bury the material deeply enough that it will not be a future issue. Usually 20cm is plenty for a lawn area. If instead you might be using the area for gardening I would put it down 40-60cm so it would not be disturbed again.
As you are digging up and moving the material sift through it to remove the rusty metals and pieces of glass and put those in recycling or in your household trash. Small pieces of rock are not a problem buried down deeply enough for either grass or garden vegetables.
Ashes from burning are not horrible for a garden if it was just pieces of wood and other organic materials that were burned there. You can mix some of this with your topsoil as you are filling the hole back in.
If you suspect the soil is contaminated with oil or other things you do not want at all then you are looking at either getting rid of it in your trash or having to pay someone to take it. This is not a fun situation to be in when you do not know what is in there.
Contaminated wastes in our area require special handling and the county has a scheduled drop off date for various materials so that would be something you could ask the local waste officials.