Glencore's Mangoola coal mine expansion at Muswellbrook deemed a threat to farm land that's 'an extremely limited resource'

Future: Glencore's Mangoola coal mine 20 kilometres west of Muswellbrook in the Wybong valley. The company has proposed expanding the mine north to extract an additional 52 million tonnes of coal.
Future: Glencore's Mangoola coal mine 20 kilometres west of Muswellbrook in the Wybong valley. The company has proposed expanding the mine north to extract an additional 52 million tonnes of coal.

THE Department of Primary Industries has strongly criticised mining giant Glencore for appearing to make no attempt to avoid or remediate impacts on agricultural land as part of a plan to expand coal mining at its Mangoola mine west of Muswellbrook.

In a short but pointed submission DPI agricultural land use manager Tamara Prentice rejected Glencore's agricultural impact statement for Mangoola as unacceptable, for failing to address how the project will impact key farm land in the Wybong valley.

The DPI rejected Glencore's plan to use more than 140 hectares of Biophysical Strategic Agricultural Land (BSAL) for biodiversity offset purposes because it was "the most productive land in NSW and an extremely limited resource", Ms Prentice said.

The DPI is one of a number of government departments and authorities to raise serious questions about the Mangoola expansion.

"There is no demonstration that the project attempts to avoid or remediate agricultural impacts," Ms Prentice said in a submission to the Department of Planning, which is assessing Glencore's plan to extract an additional 52 million tonnes of coal from Mangoola until 2030 by jumping Big Flat Creek and mining north of the existing site.

The new plan was proposed after a 2014 approval lifted Mangoola's extraction from 10.5 million tonnes to 13.5 million tonnes, bringing forward the mine closure from 2029 to 2025. It also comes 12 years after environment groups staged some of the state's first large climate change protests at the Wybong site, when Mangoola was known as the proposed Anvil Hill mine.

Legacy: An aerial view of the giant Mangoola coal mine at Wybong. Picture: Lock the Gate Alliance.

Legacy: An aerial view of the giant Mangoola coal mine at Wybong. Picture: Lock the Gate Alliance.

In the Department of Primary Industries submission Ms Prentice questioned the Mangoola expansion's cost benefit analysis after noting key agricultural production data was missing, which weakened the "rigour" of Glencore's assessment.

There was "no investigation into the cumulative effects of mining in general, and this project specifically, on the loss of agriculture in the locality and region", and the impact on agricultural employment in the Hunter was not assessed "beyond a statement that impacts are 'not anticipated'," Ms Prentice said.

In a response to submissions Glencore stood by its agricultural impact statement and said the land identified by the DPI as strategic agricultural land had not been cropped for 15 years. It put forward a consultant's assessment that the more than 140 hectares on Wybong heights was not BSAL land.

Impacts to agriculture from the mine expansion "are considered low" and Mangoola's strategies for mitigating impacts were considered appropriate, Glencore said.

Glencore has until February 14 to respond to water issues raised by the Independent Expert Scientific Committee on Coal Seam Gas and Large Coal Mining Development (IESC), after the mine submitted groundwater data from a single month in 2017 which showed water quality guideline exceedances for 11 metals, including lead, arsenic, aluminium and chromium.

The limited data showing "poor water quality... suggests that water from the pit water dam may add metal contaminants to the Hunter River, if not treated prior to discharge", the IESC said in a report which also questioned the reliability of Mangoola data predicting "large cumulative reductions in flow to Big Flat Creek" because additional mining would reduce its catchment by half.

The IESC also asked for more information about Mangoola's proposal to permanently retire 320 megalitres of water it can access under licence from Wybong Creek after data showed additional mining would reduce flow in the creek at that level. Such a plan "would not mitigate impacts to Big Flat Creek", the IESC said.

Workers: The Mangoola coal mine expansion plan will secure the jobs of 400 workers between 2025 and 2030 after an accelerated production approval brought forward a coal reserve exhaustion date to 2025.

Workers: The Mangoola coal mine expansion plan will secure the jobs of 400 workers between 2025 and 2030 after an accelerated production approval brought forward a coal reserve exhaustion date to 2025.

In a strongly worded submission Muswellbrook Shire Council criticised the expansion plan assessment for minimising or failing to acknowledge long-term impacts, including a projected 500-year recovery period for Big Flat Creek.

"What mechanisms will Mangoola put in place to take responsibility for ongoing issues after mine closure?" the council said.

It called for a condition of consent requiring Glencore to secure "lifestyle housing blocks" in Wybong after the mine closes, and to provide replacement housing for people to return to the area after data showed a dramatic population drop following the start of mining at Mangoola in 2010.

The council rejected Glencore's estimate that agricultural productivity loss over the life of the mine was just $930,000, and that local businesses benefited by more than $92 million. The council said only 8.7 per cent of supplier expenditure was paid to companies with offices in Muswellbrook shire.

A Glencore proposal to build a 5.4 metre overpass on Wybong Road to allow the mine's northern expansion was "of concern to council" because of the road's use by oversized trucks which cannot cross the Hunter River Bridge on the Denman Road. Council records showed 62 trucks higher than 5.4 metres used Wybong Road between January and June, 2019.

In its response Glencore agreed to a new plan for an overpass to accommodate much larger oversized vehicles.

While Muswellbrook Chamber of Commerce supported the Mangoola expansion to provide job security for more than 400 Mangoola workers after the existing coal reserve is exhausted by 2025, the Wybong Concerned Landowners Group slammed further expansion of a mine that "should never have been approved".

"The local community was devastated and has suffered all the negative impacts from a quiet rural area being subjected to a large open cut mine as a neighbour. No benefits have come to our local community," the group told the Department of Planning.

In its response Glencore said the expansion proposal would have a net benefit to NSW of more than $400 million, including royalties of more than $120 million.

It was "a logical continuation of the existing mining operations at Mangoola Coal Mine" that would "maximise efficient recovery of the state's coal resources", Glencore said.