Contact Energy To Clean Up Waikato River Discharge

Contact Energy To Clean Up Waikato River Discharges

Contact Energy today announced a major new initiative to improve the quality of the water discharged into the Waikato River from its Wairakei geothermal plant.

“Contact has listened carefully to the submissions it has received from river users and communities on its application to renew resource consents to operate its plant at Wairakei,” said Contact’s chief executive, Mr Steve Barrett.

Contact had already pledged in its 2001 resource consent renewal applications to substantially remove hydrogen sulphide from the plant’s cooling water discharge, which was the primary concern identified in scientific studies prepared for Contact.

“We are now adding to that commitment our proposals to remove or reduce other trace elements, including arsenic, which are found in small quantities in the separated geothermal bore water.

Waikato River water is already treated by companies such as Watercare to ensure that it is suitable for drinking. Contact’s commitment will improve the quality of the water in the river prior to such treatment.

“We will be reducing Contact’s discharges to the maximum extent practicable and will consider the feasibility of various options including treatment or reinjection techniques,” Mr Barrett said. “We will be exploring the best options to reduce discharges over the next few months.

“The most likely options are water treatment and further outfield re-injection, where water is returned underground but away from the geothermal field. These two methods are more sustainable than increasing the level of re-injection of water back into the geothermal field itself which will quench the Wairakei-Tauhara field and reduce the lifespan of a nationally important source of electricity generation.”

The initiative will be implemented once Contact’s application for a resource consent renewal to operate the plant is finalised. It is expected to take several years to fully implement and will require construction of new treatment facilities.

Generation Operations Manager David Hill said that the decision reflected Contact’s ongoing commitment to reducing the environmental effects of its operations.

“We have a commitment to clean up discharges from the Wairakei geothermal field.

“We have listened to the key interested and affected parties including the local hapu collective group, Department of Conservation, Taupo District Council and Watercare and worked with them to find the best way to improve our environmental management.”

Mr Tom Walters, a spokesperson for the Wairakei-Tauhara Hapu Collective, which has worked closely with Contact on the matter, welcomed the decision.

“When the New Zealand Electricity Department built the Wairakei plant in the 1950’s little thought was given to the effect of the river discharges,” said Mr Walters. “It’s great news that the company is now turning its attention to dealing with these discharges to the extent that it is proposing. We have had very positive discussions with Contact on a number of issues and are delighted that these have resulted in this initiative.”

Mr Paul Green, Conservator of the Department of Conservation Tongariro-Taupo Conservancy, is also very pleased with the decision.

“We have been working jointly with Fish & Game New Zealand over the last few years to highlight to Contact Energy our concerns with the Wairakei discharges. We really appreciate that Contact has listened to input from the community prior to the formal RMA hearings and is prepared to alter its approach on the basis of understanding those concerns,” Mr Green said.

Contact is aware that some ventures rely on the existing supply of separated geothermal water from Wairakei. Some river discharge will probably have to continue to permit these ventures or activities to remain viable.

Mr Hill said the decision was an important milestone in the company’s environmental management.

“Contact Energy wants to maintain its operations in the region in both an environmentally responsible and commercially sustainable manner. We are very pleased to make continued progress in this area.”

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