National list MP Maureen Pugh and National leader Simon Bridges at a rally in Greymouth to oppose Government policies.

Claims the West Coast has 1000 years worth of coal left to mine have been debunked.

National MP Maureen Pugh shared the statement on Twitter, but was repeating the assertion made by Bathurst Mining chief executive Richard Tacon at a recent rally of about 4000 West Coasters concerned about Government policies affecting the region's economy.

National Party leader Simon Bridges was there, as was West Coast-based list MP Pugh.

A Twitter user asked Bridges and Pugh if the West Coast's "best course of action is developing more sustainable tourism like the Paparoa Track or Old Ghost Road, or mining coal until it's all gone?"

Pugh responded: "We have another 1000 years' of reserves so we'll have come up with an alternative by then."

She was bombarded with comments, including from one Twitter user who said: "Simon, this MP is doing more harm to your party than you are. Did neither of you see the #climatestrike in the media?"

Joanne Carroll/Stuff Bathurst Resources Ltd chief executive Richard Tacon claimed there was 1000 years worth of coal left to mine on the West Coast. MBIE says a more realistic estimate is 96 years.

The Ministry of Business, Innovation and Employment (MBIE) has said 96 years is a more realistic figure for the amount of coal left on the Coast.

The West Coast has about 664.1 million tonnes of coal resources and reserves left, but not all of the coal could realistically be recovered.

Based on New Zealand's annual consumption of 2.5 million tonnes, the West Coast had 266 years' worth of coal left.

MBIE said a more correct estimate would be to include realistic recovery rates, which showed there was only 96 years of coal left.

Bathurst Resources Ltd chief executive Richard Tacon told the rally there was about 800 mining jobs on the West Coast.

However, Development West Coast figures show only 470 people were employed in mining on the Coast in 2018.

Tacon on Friday said his figures included alluvial gold and quarry workers, which were "not counted as miners in traditional head counts by [Government] agencies but the general public regard these as mines."

At the rally, Tacon also said there was no alternative to coal for making steel and there would be no dairy in the South Island without coal.

"There is no alternative to using coal in those processes. We don't need an alternative. We've 1000 years of coal supplies on the Coast to meet the needs what is really a small part of our overall business but a really important part because it is returning export dollars," he said.

Joanne Carroll / Stuff Grey mayor Tania Gibson makes an impassioned plea for the Government to listen to West Coasters.

"It's mining and the environment, it's not mining or the environment. It's not a black and white binary decision. Governments and companies around the world are realising its the way to go," he said.

Tacon on Friday said his comments related to the supply of coal to the West Coast's dairy plant, which used about 65,000 tonnes a year.

"The number from MBIE would be 100 per cent correct for the whole of New Zealand coal use per annum."

Fonterra is the country's largest coal user. It says it burns about 500,000 tonnes a year, resulting in emissions of 873,000 tonnes of carbon dioxide a year.

Coal Action Network Aotearoa Cindy Baxter said there were plenty of alternatives to coal for the dairy industry. Fonterra had committed to being carbon neutral by 2050 and had already started using wood biomass in its dairy processing.

"The world is rushing to find alternatives. There have been massive strides forward in finding alternatives to coal for steel," she said.

ALDEN WILLIAMS/STUFF Bathurst's coal handling facilities for Stockton mine, at Ngakawau on the northern West Coast.

New Zealand should stop burning any more coal if it was serious about reducing climate change, regardless of how much coal was left, she said.

"The West Coast is already seeing very real impacts of climate change, which is costing jobs, causing slips, causing dumps to be scattered all over our coastlines," she said.

Tacon and Pugh did not respond to requests for comment, but Pugh earlier told Parliament West Coasters felt uncertain about their futures. She said they wanted to be consulted and the Government was not delivering on its promise of a "just transition".

Pugh was dragged into the limelight last year when Botany MP Jami-Lee Ross released a recording of Bridges describing her has "f...ing useless". She later publicly forgave Bridges.

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