Tipperary Co-op and the Arrow Group, which is owned by Dawn Farm Foods, remain on the Environmental Protection Agency’s (EPA) national priority sites list.
The latest list identifies eight sites that are the focus of the EPA’s enforcement activities.
Three of these sites; Tipperary Co-operative Ltd, Merck Millipore Ltd and Limerick Gasworks, account for 62% of all odour complaints to the EPA from industrial and waste facilities.
Darragh Page, programme manager of EPA’s Office of Environmental Enforcement said: "The number of odour complaints received by the EPA in the first six months of 2020 was more than three times that of the same period the previous year.
“The COVID-19 pandemic has resulted in widespread disruption to society and businesses with many licensees temporarily closing or scaling back their activity.
“However, at a time when everyone was being asked to restrict their movements and to stay at home, it is unacceptable that a number of industrial and waste sites caused great distress to those living around them by emitting offensive and potentially harmful odours.
“Sites that continue to breach their licence conditions and cause environmental pollution can expect further enforcement action from EPA,” he said.
The list is a key enforcement tool for the EPA and is used to target enforcement efforts at the poorest performing sites and to drive improvements in environmental compliance.
Prosecution is often the end result of a site appearing on the list, with proceedings being initiated against the majority of the sites on the current list.