I have updated this investigation on 20th October.
Tank 1 on this site is currently showing improvement and therefore I have changed the status of the investigation to Fairbanks Monitoring. You will find this on the investigation report that will be sent out on Thursday.
Tank 5 has been recommended to have a PLIP B however the performance of this tank has improved recently. I would recommend that if the PLIP B has not been completed yet that it is delayed for a week whilst I monitor the performance of the tank this week to see if the improvement continues.