New environmental permit for the Meltola wastewater treatment plant

The Regional Administrative Agency of Southern Finland has granted an environmental permit for the Imatra wastewater treatment plant.

In the granted permit, the permit conditions are tightened across the board.

—As a result of the renovation, the wastewater treatment process will be modernized and more efficient. The new facility is sized so that we can achieve the stricter conditions, water supply manager Kari Pietarinen says.

A transition period of one year has been granted for the new terms and they will enter into force at the beginning of 2024.

The bypass and overflow points must be equipped with measuring equipment

The limit values ​​set for treated wastewater in the new environmental permit are stricter than before. 

Starting in 2024, 95 percent of phosphorus, 95 percent of solids and 85 percent of nitrogen must be removed.

—The new values ​​comply with our proposal and are therefore expected, Pietarinen states.

In addition to the limit values, several other permit conditions have been set in the permit order.

The need for sanitation of the wastewater treatment plant must be determined by the end of 2025. The report must reveal what kind of effects the operation of the treatment plant has on the use of Vuoksi's waterways.

The license conditions also oblige to equip the bypass and overflow points with equipment that measures and registers the leaks.

"We don't have this kind of equipment yet, but the number of overflows and overflows has been estimated by other means," says Pietarinen.

Sewerage network renovation plan every five years

In the future, the condition of the sewer network must be checked regularly every five years. Based on the inspections, a maintenance plan is drawn up, according to which the network is maintained and renovated. The first plan must be made during 2023.

Noise limits have also been set for the wastewater treatment plant, as there is a residential area in its vicinity. The sound coming from the treatment plant must not exceed 55 decibels in the courtyard of residential buildings during the day. At night, the limit is 50 decibels.

—Noise restrictions have been taken into account in the renovation, and the limits should be realized with the planned sound insulation, Pietarinen states.

The renovation of the Meltola wastewater treatment plant began in 2021. At that time, a new environmental permit was also applied for for the plant, as the operation of the wastewater treatment plant will change significantly as a result of the renovation.

The estimated completion time of the renovation is autumn 2023.

For more information:

Water supply manager Kari Pietarinen, kari.pietarinenimatra.fi (kari[dot]pietarinen[at]imatra[dot]fi), tel. 020 617 4399