Letter from Julie – Mudgee District Environment Group
When my family first bought our property Gleniston in 1973, we were enthralled by the beauty and soul of this unique river – where clear water meandered through beds of sand and peat, between soaring sandstone cliffs and gorges, like a scene from the Northern Territory. At Ulan, a pit pony named Mary still pulled the coal carts that supplied fuel to the local hospital furnaces.
By the early 1980s we were horrified to learn that White Industries were planning a huge open cut coal mine that involved diverting the headwaters of the Goulburn River and mining of the river bed and adjacent alluvial flats. An inadequate Environmental Impact Statement (EIS) was produced and my family’s submission along with many others challenged the wisdom of the diversion and long term impacts on groundwater and river flow.
The mine was given the go ahead and in 1983 further permission to expand the open cut plus two additional underground mines was granted. The Goulburn River was diverted into a man-made chasm for approximately 4 kms of its length. In the process tonnes of sediment washed downriver, depositing dirt and clay onto the sandy bed.
After 25 years the legacy of the diversion channel remains: the unstable, poorly battered vertical walls are still eroding, shedding sediments into the river, while around 1 million litres of water per day is lost from the base flow into the old mine workings. Over time there is also a significant risk that mine waste (buried in the mining void adjacent to the channel) may contaminate the river. While the underground mining has been shown to significantly interfere and degrade the groundwater resources of the area.
History of Coal Mining In The Upper Goulburn River Catchment
1. Water, water everywhere!
With the development of the underground mine Ulan Coal Mines became a ‘wet’ mine. They had to dewater or pump an apparent endless source of water – more than they could handle. With government permission in the mid 1980s they discharged mine water1 into the Goulburn River, 3-4 megalitres/day increasing to 11-15 megalitres/day by the latter 1990s.
We wrote letters, started collecting information, monitoring the river and graphing the results. We presented them to the mine and EPA and invited them to take a look at the salty deposit forming on the river banks. The EPA went into a huddle and informed the mine they had to “work towards NIL Discharge”.
Groundwater inflow to the underground mine was up to five times the predicted amount stated in the 1998 EIS and 2001 Water Management Plan! This amount of increase was not anticipated by earlier drilling, modelling or hydrogeological surveys of the area, unless leakage from aquifers overlying the coal seam was ‘contributing the majority of the inflow’ (National Centre for Groundwater Management 1998)
Recent more comprehensive groundwater investigations by Ulan Coal Mine (2008) have confirmed that mine subsidence cracks the overlying strata and drains upper aquifers. The current water make of around 15 million litres per day is predicted to exceed 18 million litres per day by 2011 (3 years).
The water pumped from the mine creates a regional ‘drawdown’ effectively diverting natural flows of underground water that normally provide the base flow to the Goulburn River.
2. Decline in Water quality and River Flow
By the early 1990s, the ensuing decline in the quality and reliability of the river water flow made it necessary for us to establish an alternative water system and bore at considerable personal cost. Our worst fears had been confirmed.
Groundwater in contact with the disturbed coal seam becomes saltier and more acidic the longer it remains. We urged the mine to remove the water before it became contaminated by the disturbed coal seam and release it down the river as environmental flow to compensate for the ‘lost’ base flow to the river.
In response to EPA regulations and local pressure Ulan Coal Mines developed some engineering ‘solutions’. Initially evaporating the water, called the ‘Big Gun’ method, where water cannons sprayed skywards concentrating a salty brine in the old mine pit below.
This was followed by the Bobadeen Irrigation Scheme where water was disposed through the irrigation of pasture to produce stock fodder.
Over the subsequent summer months of 2001-2006 the river further deteriorated and ceased to flow. This lack of surface flow for extended periods was unprecedented – even in the severe 1980s drought the river maintained a flow (pre mine expansion). Any minimal flow over the clay imbibed sandy bed grew algae. It was a very sad sight.
The excess water problems at Ulan Coal mine continue. In 2008 the EPA granted permission for the Mine to discharge water to the river at around 800-900 EC (twice the natural background level) using a desalination or reverse osmosis plant to improve the water quality. This ‘environmental flow’ may replace some of the loss of base river flow caused by the mining interference but does not solve the long term problem resulting from the fracturing and dewatering of the groundwater system.
New Coal Mines
Two more huge coal mines have been approved for this area – Wilpinjong & Moolarben Coal Projects to produce 8 and 10 Million tonnes of coal per annum.
Ulan Coal mine is also expanding operations, in effect another new coal mine. It is proposing to double its coal output to 20 Million Tonnes per year for 21 years. It uses the widest longwalls in the southern hemisphere (400m).The environmental impacts of the resulting subsidence are still to be determined.
All these mines directly impact on the headwaters and groundwater that feed the Goulburn River.
The cumulative impacts of these three mines threaten the integrity and long term viability of the Goulburn River a major tributary of the already stressed Hunter River (see www.savethedrip.com for further information).
Moolarben Coal Project – Plans to long wall mine up to 80m from the bed of the Goulburn River and open cut three large areas in the picturesque Moolarben valley. straddles the headwaters of the Goulburn River. The long wall mine is to come within 400m of the magnificent sandstone cliffs and gorges along the river – including significant landforms such as ‘The Great Dripping Wall’ (The Drip – an outstanding spring-fed cliff line) and ‘The Corner Gorge’. Both are widely used recreational and educational sites within 20 minutes walk from the main Ulan Cassilis Road.
Long wall mining within a kilometre of these fragile cliff lines would threaten their stability, undermine public safety and damage our natural heritage. The area is also of considerable cultural importance, with important examples of rock art in undercut caves along the river.
Wilpinjong Coal Project – has commenced mining, over the next few years it will divert a number of creeks around the new proposed open cut coal mining area and remove 290 hectares of remnant woodland vegetation, in a valley home to a range of endangered species and communities. This huge open cut mine is likely to impact on groundwater in the area and has the potential for offsite saline and acid drainage.
Irreversible environmental damage is an inescapable consequence of coal mining in this sensitive catchment. This was predicted in the 1980s but there were minimal amendments to the mining conditions or monitoring of the outcomes. We are now being given assurances that “the highest environmental conditions will be applied”. The new environmental conditions basically require monitoring the effects and mitigating the impacts – after the event.
We are now locked into this massive expansion of the coal industry in this area for at least the next 20 years. The community will bear the real environmental cost of coal mining. Our rivers are part of our natural heritage and should be protected for all Australians now and into the future. We should not be expanding this unsustainable, dirty and destructive industry that is a direct threat to climate stability and our precious water resources.