The union representing mine workers says the panel that gave consent for a mine under a Coromandel town was thorough and and considered the issue of vibrations from the mining operations.
Newmont Waihi Gold was granted consent on Monday to develop a mine that will sit beneath about 45 homes in Waihi and operate 24 hours a day, seven days a week.
Consent for the Correnso mine was granted under conditions that include restrictions on the magnitude and number of blasts, and property purchase and other assistance for affected homeowners.
The Independent Commissioners' Hearings Panel said it was the first area of gold mining directly below a residential area of New Zealand which indicated a precautionary approach was appropriate.
The Green Party says Waihi residents will suffer land instability and vibrations.
Green MP Catherine Delahunty says residents who wanted to protect their homes were outgunned by expensive experts hired by the mining company to present their case to commissioners.
"The local people couldn't afford expert testimony to dispute the company's experts. It's a David and Goliath situation every time, because people just don't have the money to produce the international expertise to show that their effects are more than anecdotal."
The Engineering Printing and Manufacturing Union says mining jobs have been winding down in other parts of Newmont's Waihi operations and the new mine will provide a much-needed boost for local employment and the town's economy.
Assistant national secretary Ged O'Connnell said the panel handled the application fairly and thoroughly.
"The commissioners asked for further reports in terms of the vibration elements of it. It seems to us that they went into it in a very thorough manner and process, and the interests of all parties have been balanced out coming to this decision."
The mine will have up to 400 fulltime employees, but most would transfer from other operations in the town as they wind down.
Stressful time for some
A spokesperson for a Waihi action group says some people are unhappy and fear falling housing prices.
Collette Spalding, of the Distressed Residents Action Team, says she is not against the mine but does not want mining under people's homes.
Tracey, a mother who has lived directly above the site for the past 12 years, says she feels helpless about her family's situation, as she can't afford to move.
She says many residents are distraught at the prospect of the mine.
"The stress that it's putting on families is just horrific - because at the end of the day, nobody can give a guarantee on what is going to happen, whether a house is going to withstand it."
Retired resident Merv Lauder says he fears the decision will set a precedent for more mining in the town.
The Hauraki District Council received 500 written submissions on the application with the majority in support and 115 opposed.
Newmont Waihi Gold sought a consent term of 20 years, but the hearings panel limited it to 10 years, and rejected consent for a much wider project covering more than 700 hectares.
The company says a lot of residents' worries may come down to misperceptions about underground mining.