Non-PRO English to Arabic Other Food & Drink product waste

It is important that only product waste found at that station be placed in these buckets.
Product waste happens in a restaurant. It may be caused by a preparation error or by overproducing product.

Obviously, they mean the products that expired of get defected for any reason and become waste in a restaurant. The first sentence is talking about the waste and the second one is about the situation. I need a correspondent that could fit in these both instances. Do you have any suggestions?

Thanks in advance,