Moving empty packaging to Europe from UK and returning with soil in the packaging

My company is expanding into the EU and we are intending on moving our own packaging from the UK to the EU. Filling the packaging with soil samples and bringing the samples back to our lab for analysing. Re-usable packaging being Plastic pallets, clear plastic tubes with end caps and straps. I’m trying to understand if we move 20 pallets of reusable packaging to Europe can we bring them back into the UK in smaller batches, with soil samples in them or do we need to bring the same 20 pallets back at the same time? Does having soil samples in the packaging constitute as changing the packaging in anyway? Currently, I understand, soil samples for analysis can be imported into the UK from the EU without restrictions.

Hi,
 

I would advise contacting the Customs and International trade helpline on 0300 322 9434   . Thank you.