The Environmental Protection Agency (EPA) has confirmed a problem of odours near the Merck Milliipore factory in Carrigtwohill, Co Cork, has re-emerged in the past fortnight.
The EPA said its officials detected intermittent organic and musty odours in the vicinity of the east Cork plant after a number of reports of bad smells in the area in early January.
Members of the public had complained that the odours were similar to those reported in March and April last year which resulted in the EPA instructing Merck to take “significant action” to address the problem.
The EPA said inspectors had detected an odour at the boundary between the factory and the N25 on January 15, although no bad smells had been detected in the Carrigtwohill area earlier during a wider inspection.
It said the same odour was subsequently experienced in an area of the Merck factory during an inspection of its wastewater treatment plant.
At a meeting earlier this week, the EPA ordered Merck to investigate and report back on the source of the recent odour as well as to take corrective actions to ensure all odour-generating activities on the site were fully and consistently controlled.
The EPA has been monitoring the situation at the Tullagreen factory since complaints were first raised by local residents in December 2019.
The problem has been linked to the odour abatement system at the factory’s wastewater treatment plant with the EPA stating parts of the equipment were unsuitable and needed to be changed.
Merck recently installed a heater at the facility as a measure to contain the problem during periods of cold weather but its commissioning is not due to be completed until Sunday.
It has also proposed installing a regenerative thermal oxidiser (RTO) as a long-term measure to address the problem of odours but it is not due for completion until late 2021.
Merck had been instructed by the EPA to reduce discharges to its wastewater treatment plant by 20% last summer to reduce the odour being generated.
In November, the EPA agreed to a proposal by the company to gradually increase discharges above 80% on the basis that it would not generate any odours offsite.
However, the EPA said the wastewater treatment facility was currently operating below 80% of its capacity.
Merck says it has worked in recent months to treat odour omissions from the facility. It said short-term measures had been implemented while it had just completed medium-term measures with the installation of additional carbon beds.
It expects operation of an RTO from late 2021 will facilitate the removal of additional levels of odour compounds and increase capacity of its plant.