WILHELMSHAVEN (dpa-AFX) - An expert report commissioned by Deutsche Umwelthilfe (DUH) calls into question the permanent biocide discharge at the LNG terminal in Wilhelmshaven approved by the Lower Saxony authorities. The terminal operator Uniper uses chlorine extracted from North Sea water as a biocide to prevent the seawater systems of the LNG terminal ship from becoming overgrown with algae and mussels, for example. Such continuous chlorination "cannot be regarded as the best available technology," according to the statement by Hamburg-based laboratory LimnoMar published Thursday by the environmental aid group and obtained by Deutsche Presse-Agentur. The process is not compatible with either national laws or the EU Water Framework Directive, it said.

The authors recommend that the process at least be changed to so-called shock chlorination - in other words, that chlorine only be used when the fouling pressure of algae and mussels requires it. In the long term, the report says, an environmentally friendly cleaning process based on ultrasound, for example, should be used instead of chlorine.

Umwelthilfe and also other environmental protection associations have long criticized the discharge of chlorine-treated wastewater into the Jade at the LNG terminal ship "Höegh Esperanza," which went into operation in December. Among other things, they fear damage to the adjacent Wadden Sea ecosystem. "Electrochlorination is an outdated technology, extremely harmful to the environment and also not legally permissible," said DUH energy expert Constantin Zerger.

The association again called on the Lower Saxony licensing authority to order the retrofit to a different cleaning process. "Otherwise, we will initiate further legal steps based on the expert opinion to protect the Wadden Sea National Park from the discharge of the toxic biocide," Zerger said.

In contrast, the licensing authority, the Lower Saxony State Agency for Water Management, Coastal Protection and Nature Conservation (NLWKN), had previously stated in the permit that the chlorine-based purification system was "state of the art." The Ministry of the Environment in Hanover stated on request that the statement of the expert opinion was not correct. The basis for determining the "state of the art" are technical environmental standards of an internationally recognized standard. This recommended for a floating LNG import terminal (FSRU), "(...) that a chlorination system should be in place when using seawater as a heating medium."

Terminal operator Uniper said in response to a query that the use of other cleaning methods, such as ultrasound, had been investigated. "So far, no alternative process met the special requirements that are placed on an application on the FSRU "Höegh Esperanza"." The licensing authority, however, has required Uniper to submit proposals by the summer on how to reduce biocide use. To this end, together with the Höegh shipping company, it is "currently in numerous discussions" with manufacturers, suppliers and experts, Uniper further announced./len/DP/zb