Auckland's Volcanic Cone Society is fighting against a Karaka man's application for permission to build his dream home atop a huge, previously undiscovered volcano.
Wayne Valder, who owns the Karaka property, is planning on building a five-bedroom house with a basement and driveway on the site.
Valder had been working on the plans since purchasing the land in 2014, but it currently sits vacant.
An Auckland Council spokeswoman said five submissions have been lodged against the application for permission to build the home.
A planner assigned to the consent application would begin to assess each submission early next week.
Any issues raised would be included in a report on the application, which would recommend the next steps.
One of the submissions, filed by the Auckland Volcanic Cones society, recommended rejecting Valder's application.
Spokesman Greg Smith described the west Aucklander's plans as being "considerable" in size.
The site needed further surveying to assess the value of its landscape and geography, he said.
"This volcano is like the elephant in the room - I mean it's so big you can't see it."
The size nature of the volcano contributed to its rather late discovery, according to geologist Bruce Hayward.
Earlier this year Hayward was contracted by Auckland Council to survey the site after some Karaka locals raised questions about a rumoured volcano.
Hayward said he was "absolutely staggered" when he discovered an old degraded "castle and moat" volcano, by using high-tech scanning and on-site mapping.
Hayward said the find was rare - it was the first of its kind of be recognised for more than a century.
"There is an explosion crater with a tuff ring around the outside, and in the inside it's got a scoria cone," he said.
"The cone in the middle is surrounded by a moat, so it's a castle with a moat around it and then a ring of ash around that."
Valder's proposed earthworks and house sat on the outer crest of the volcano's tuff ring, with his suggested boundary for an Outstanding Natural Feature ran through the proposed house site.
"My suggested boundary was to try to preserve the crest and view of crest of the tuff ring from damage and development," Hayward said.
Smith agreed the landscape was "sensitive" and would undoubtedly be disrupted by the proposed development.
"When you actually look at the size of it - this is a huge volcano."
Smith urged council to put considerable time and effort into ensuring the natural feature was protected as much as possible.
When initially contacted by the Weekend Herald, Valder said the discovery was a surprise which was problematic to his plans.
After speaking to his lawyer, he declined to comment further about either his resource consent application or the volcano.
According to geologists' records there are 53 recognised volcanoes in the Auckland volcanic field.
A further 80 recognised volcanoes sit in the south Auckland field.
Most volcano forms in the Auckland region had been recognised and mapped in the 19th and early 20th centuries.