Myself and a colleague have had reason to visit a couple of construction sites recently for Crime Prevention Advice.
Whilst talking to the site managers they mentioned about being visited by scrap metal merchants on occasions.
Whether you are a private house, business or construction site please check that anyone who visits asking for scrap metal or other items etc are Licensed Waste Carriers. 
This means any business must register with the local Council if they transport waste ( a carrier ) or buy, sell or dispose of waster ( a dealer ) .
If you give your scrap or waste material to an unregistered carrier and they dump or Fly tip in a layby and the waste is identified back to yourselves, YOU would be liable to a fine which in some circumstances can be quite substantial.
Here is a link to find registered waste carriers or go to the https://orlo.uk/Q3Db9 website https://orlo.uk/wR0Te

Thank you PCSO 5410 Sarah