My pool has been covered in bitumen can I use a liner on this?

If the pool has been covered in bitumen, it would not be suitable to directly install a liner on top of it. The bitumen could leak through and cause discoloration and other issues with the liner. In this case, a more thorough solution would be required to prepare the surface for a liner or other type of pool surface. This might include removing the bitumen or sealing it with a suitable barrier that would prevent any interaction with the liner. Consultation with a pool professional who has experience with this type of situation would be highly recommended to determine the best course of action.