The EA has today published RPS C25 which sets out when you can accept LFD testing waste that has been coded 18 01 04 and 18 01 07 or 20 01 99 without the need to formally vary your Permit.
The conditions in the RPS must be followed and written agreement must be obtained from the EA before using it. Note that the EA reserves the right to decline a request if the site that is the subject of the request is performing poorly.