Miner OceanaGold has had its bid to buy land for a new tailings dam near its Waihi mine turned down by the government.

The ASX-listed firm, New Zealand's biggest gold miner, is mostly owned by US and UK investors and needed Overseas Investment Office approval to buy about 178 hectares of farmland on Trig Road south-east of the town.

Its provisional recommendation, provided in November, was that the purchase be approved.

But while Associate Finance Minister David Clark believed the purchase was likely to create "substantial and identifiable benefits", coalition colleague and Land Information Minister Eugenie Sage did not.


"Minister Sage does not believe using productive rural farmland to establish a long-term tailings reservoir of mining waste creates substantial and identifiable benefits," the ministers said in a joint statement.

When ministers are split on a decision, it is declined.

Gold has been mined at Waihi for more than 100 years. The company, which also operates the Macrae's Mine near Dunedin, produced 83,500 ounces of gold at Waihi last year and is aiming for 60-70,000 this year.

In December, the company was granted consent to extend mining there by about 12 years.

Today the company said it was extremely disappointed by Sage's decision not to allow the purchase of the two farms.

"The purchase of these properties would allow us to plan for the future and extend our investment in Waihi beyond the current life of the mine and our significant economic contribution locally, in the Hauraki region and nationally," said Kit Wilson, the company's senior community advisor at Waihi.

"We are disappointed by what we have heard but have not had the opportunity to read the decision in full. We will review the decision and consider our next steps."

Last year, an independent panel cleared the company to extend the Martha pit in the middle of Waihi slightly to the north. It was also cleared to undertake new underground mining beneath the Martha Pit, and a new area of underground workings below an area of residential, reserve and commercial land south-east of the pit.


OceanaGold estimated the project would extend the mine's life by about 12 years, and deliver economic gains of about $73 million annually for that period.

The OIO noted that ministers are entitled to determine the weight they give when considering potential benefits to New Zealand from such investments.

"The ministers carefully considered the applications. They met regularly to discuss the applications and requested additional information and advice. In February 2019 they requested further information from the applicant, which OceanaGold provided."

Also today, the Overseas Investment Office approved OceanaGold's purchase of four residential properties in central Waihi as part of its mining operation.

The office noted that the company is a significant employer in the region and has undertaken "a number of previous investments that are of benefit to New Zealand."

The land being acquired is for purposes incidental to the mining activities and the purchase meets the requirements of the Overseas Investment Act.

"The OIO is satisfied that the overseas investment is likely to benefit New Zealand."