The mine is proposed by Hunter construction company ATB Morton on a 73-hectare site where Janet Parade meets Nelson Bay Road at Salt Ash.

ATB Morton spokesman Steve Smith said most of the sand was destined for the company's Redicrete concrete plants at Tomago, Cameron Park and Berkeley Vale but some was likely to be sold on the open market.

The quarry would employ four people using front-end loaders and trucks to mine about 3.7 million tonnes of sand at a rate of about about 200,000 tonnes a year for 18 to 20 years.

At a typical price of about $15 a tonne, the resource has an indicative value of about $55 million.

Documents on display with the NSW Department of Planning show as many as 13 sandmines along the grassed and wooded strip between Fullerton Cove and Anna Bay.

"The cumulative impact of sand quarrying operations in the locality may have some adverse impacts in terms of the tourism industry which rely heavily on the natural environment of the Stockton Bight sand dunes," ATB Morton's environmental assessment stated.

Other costs included heavy traffic and "potential impacts on the value of nearby housing and lands" but the Morton quarry was planned for private land and would be screened from public view.

Despite the huge reserves of bare dunes on Stockton Bight, Mr Smith said the State Government preferred companies to take sand from vegetated ground, which is why ATB Morton had leased the Janet Parade site.

About 27 hectares of coastal blackbutt forest would be lost to mining but this was being environmentally offset by the dedication "in perpetuity" of land at Markwell, on the edge of the Wang Wauk State Forest near Bulahdelah.

ATB Morton's environmental assessment acknowledged the Salt Ash quarry would remove some "supplementary" koala habitat but said this would be replanted as the mine moved along in stages.

The proposal is on display until April 21.