Dr. Tom Ryan:

I can confirm that March was the first time we raised the issue of UV disinfection. It is only in recent years that we have been tracking the deterioration with Irish Water through sampling and measurement. The number of giardia detections was one in 2015, one in 2016, two in 2017 and one in 2018, but there have been ten such detections so far this year. There has been a deterioration in the infrastructure treating the plant. We are now convinced that this is the right way to go. We mentioned it in March. We strongly recommended it in our October audit.

The Deputy asked about the recommendation that the plant should be shut down automatically. When we came back, we found it was implemented on one of the lines only. The audit finding was very much that the shutdown should apply to the entire plant. It is clear that this was misunderstood. This was remediated when we got back out there in October.

The Deputy also asked about the lag time. The current situation is evolving. We are satisfied that we have been notified promptly. We were involved in discussions yesterday on the implementation of the boil water notice.

The Deputy also asked about the issue that arose in October. Clearly, there was an operational difficulty that allowed a window of time to happen when remedial action could have been taken. Alarms were not responded to. It was not a normal or foreseen event. The alarm is usually raised when there are operational or mechanical difficulties. We are usually notified when there is an issue. It is clear that there was a period of time the plant was operating even though alarms were ringing.

That said, once we are notified, we get involved in conversations with the HSE and Irish Water. Public health is first and foremost in everybody's mind in that regard and, as such, the boil water notice was issued and precautionary measures, which I am sure will be addressed in detail by Irish Water, were taken, such as flushing out the system before the boil water notice is lifted. I hope that addresses the Deputy's queries.