The Crown is going ahead with plans to allow companies to explore parts of Northland for metallic minerals, following feedback from iwi and members of the public.
Some submitters asked for areas not to be searched, arguing that wahi tapu sites need to be protected.
But the Ministry of Economic Development says the original proposed tender region remains unchanged and there are strict conditions in place to ensure that sacred areas are respected.
The ministry says firms that win five-year exploration permits have to engage with Maori and update the ministry once a year on how well they are getting on with iwi.
It says a permit doesn't give permission to mine - but surveys, sampling and exploration drilling can be carried out.
There is no automatic access to land and they have to negotiate with the owner to gain access.
Officials also say registered wahi tapu sites are covered under the Resource Management Act.
The area open to tender roughly stretches from Kaitaia to north of Whangarei, but excludes a big strip down the west side of Northland.
The size of any one permit will be limited to 7500 hectares.
Bids opened on Wednesday and close on 7 December.