Proof of delivery in metal recycling

Hi

We are a trading company dealing in scrap. Our business requirement are as follows.

1. In our material master we have the following materials
   1. HM
   2. LS
   3. OS
2. We have scheduling agreement for HM
3. We deliver HM to our customer say 20 MT
4. When the customer receives the material they inspect the material and classify it as
   1. HM 18 mt
   2. LS 0.5 mt
   3. OS 0.5 mt
   4. Trash as 1 mt
5. In our Inventory we will PGI HM 20 MT
6. While Billing to the customer it should be based on the items classified by the customer

My question is

1. is it possible to record in POD the materials as classified by the customer
2. If not is there a workaround

Thanks and Regards

Arun Kumar Menon