"It is certainly in our best interests to keep our staff, and we will do everything we can to do so, but if Correnso does not start production until 2015 there will be very limited work for any underground staff."
Operations at Newmont's Martha open pit and the process plant would not be affected by the production gap and would continue to operate, with Martha open pit due to close in March 2016, Mr Grindlay said.
Earlier this month, Green Party MP Catherine Delahunty launched her Crown Minerals (Homes and Residences Exemption) Amendment Bill, which will prohibit the granting of mining permits for minerals in respect of land within 300 metres of residential premises.
The bill would protect people from having minerals companies disrupt their lives, Ms Delahunty said.
Newmont Gold has permits to mine underneath land with 1100 houses on in Waihi.
"Residents should not have to be put through an ordeal, possibly lasting several years, in an attempt to protect themselves against the noise, vibration disruption, and health risks from having mineral mining underneath their homes," Ms Delahunty said.