EPA findings on chemical spill at east Mayo water treatment plant published
"The drinking water quality entering the Kiltimagh public water supply was not affected as a result of the chemical spill."
The Environmental Protection Agency (EPA) has published its inspection report on a chemical spill at Kiltimagh water treatment plant on September 3 last.
According to EPA inspector Donal Howley, the spill occurred due to 'an operational error' while filling the chemical day tanks.
The drinking water quality entering the Kiltimagh public water supply was not affected as a result of this chemical spill, the report stated.
Irish Water notified Inland Fisheries Ireland of the incident, as the chemical has discharged into the River Glore.
Inland Fisheries Ireland is conducting an investigation into the incident, the audit outlined.
The Kiltimagh water supply produces approximately 801 m3/day of water serving a population of 1,618.
Raw water is abstracted from the Glore River and treatment includes coagulation, clarification, filtration, and disinfection at the Kiltimagh water treatment plant.
This audit was carried out in response to Irish Water's notification to the EPA of a chemical spill at the plant which
The chemical spill on September 3, which overflowed from the day tanks between 8.22 and 11.01 a.m., entered the river at the discharge point, which is downstream of where the water is abstracted from the river for treatment at the Kiltimagh water treatment plant, the audit confirmed.
At approximately 10:30 a.m. on the date in question, Mayo County Council was notified by members of the public of a potential pollution incident at the Glore River and water services staff were contacted by the council's environmental section to investigate.
Water services staff returned to the treatment plant and turned off the flow at approximately 11:01 a.m. and immediately notified the appropriate personnel of the chemical spill and began on-site clean-up.
A contractor attended the site on September 4 to carry out a full clean-up of the water treatment plant's internal channel network and sandbag the channel outlet to ensure no further discharge occurred during the clean-up period.
The council also carried out remediation works from the water treatment plant outlet to the confluence of the Glore and Pollagh rivers on September 4.
A jet-vacuum system was used to remove isolated pockets of polyaluminium chloride deposits that had accumulated in areas with restricted river flows.
The EPA issued the following recommendations.
1. Irish Water should ensure that standard operating procedures for chemical use on-site (acceptance of chemical deliveries, chemical transfer, chemical management) are made available at the Kiltimagh water treatment plant.
2. Irish Water should ensure that operators receive the appropriate training in relation to chemical use on-site at water treatment plants.
3. Irish Water should review the sludge management procedures at the Kiltimagh water treatment plant to ensure sludge arising from the treatment processes is adequately managed.
4. Irish Water should carry out further sampling of the River Glore and carry out further remediation works if necessary, to ensure no further polyaluminium chloride residuals remain in the river.
5. Irish Water should repair the pipe located in the manhole inspected during the audit, as appropriate.
Under the European Union (Drinking Water) Regulations 2014 as amended, the Environmental Protection Agency is the supervisory authority in relation to Irish Water and its role in the provision of public water supplies.