A prominent 16ha block bordering the seaside settlement of Rapahoe and State Highway 6 could be subdivided into lifestyle-size residential blocks.
However, developer Terry Birchfield says he is also exploring the possibility of mining the site, which has a spectacular Twelve Apostles Range backdrop.
Tall flax and scrub and some bush re-growth has been flattened or cleared and new drains formed since Birchfield purchased the property earlier this year.
Fox River resident Andrew Beaumont contacted the Greymouth Star concerned that work might be destroying what appeared to be a natural wetland.
"They're chopping into that regrowth of bush and putting in drains," he said. "It looks to me like a very large native wetland area that could be looked after."
However, Birchfield said the block was not naturally swampy, despite passing impressions. Run-off from the adjacent highway meant water had nowhere else to go.
"The road drain runs across into our place and there is no drain running away from it, and it's made a bloody mess of it. The road board (NZTA) is growling at me. We're taking the water from the other side of the road."
The site itself had good natural drainage on sand, about 1m to 1.5m beneath the top layer of soil, he said.
The future subdivision would be serviced with power and connected to water, being close to services in Runanga and Rapahoe.
Any development was a fairly "slow job" but the land was attractive for subdivision given its proximity to the coastline.
At the same time, test sampling for possible sand-based mineral content had been undertaken.
"There's all sorts of minerals around these days. Gold is one of them, but we're all a bit ahead of our time," Birchfield said.
West Coast Regional Council acting consents and compliance manager Rachel Clark said the council was aware of preliminary work for some kind of future development along Rapahoe straight.
"We are reviewing it, and we need to look into it. I believe they were doing most of what they were doing under permitted activity rules."
Grey District Council senior planner Michael McEnaney said the site was not an identified significant natural area within the district plan. Nor had it been identified as an outstanding natural landscape or an area of high natural character within the proposed Te Tai o Poutini Plan.
The NZ Transport Agency has been approached for comment.
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