British Gypsum plans to retain more than 150 jobs until 2044 by extending the south of Bantycock Quarry near Newark, Nottinghamshire.
The company currently has permission until 31 December 2027 to extract high-grade gypsum in the northern part of the site near Fernwood and Balderton, with final restoration to be completed by 31 December 2029 .
British Gypsum, which is part of French multinational Saint-Gobain Group, said that the reserves were anticipated to be used up by 2024/25.
The southern extension will allow the company to extract up to a further five million tonnes of high-grade gypsum.
The gypsum at Bantycock Quarry lies close to the surface and is found in beds, or seams, separated by a type of mudrock (interburden) and also covered by clay/mudrock (overburden) and soils.
Soil stripping will be followed by archaeological investigations before the overburden is removed and gypsum extracted.
A public consultation is expected to last four months before Nottinghamshire County Council makes a decision by the middle of 2021.
Gypsum is used to produce plaster products for sectors including ceramics, food, brewing, decorative work, medical and dentistry.
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