The Environmental Protection Authority has had to extend the submission period on an application to mine the seabed off Taranaki because it was tardy in posting key documents on its website.
Trans-Tasman Resources wants to mine iron ore from 65 square kilometres of seabed, 22 kilometres off the coast of Patea.
Submissions on whether a marine consent should be granted were supposed to end on Thursday.
However, the authority has admitted documents were not available on its website for submitters for all of the submission timeframe.
Radio New Zealand understands this includes an overview report of the project and maps.
Submissions now close on 28 January next year.