groundwater

Protect Our Water Alliance

Dendrobium Damage Update #2

South32 has finished mining Longwall 17 in “Area 3b” in the Dendrobium Mine, which of course is on unceded Dharawal Country, and just north of the Avon Reservoir.

Your faithful friends here at POWA have trawled through the End of Panel report, and distilled some Dendrobium Damage for you. Spoiler alert: longwall mining is highly destructive, and South32’s contractors only appear to have surveyed a small part of the undermined (and adjacent) area.

Update #2

The average daily inflow to Area 3b during Longwall 17 extraction was 5.2 megalitres per day (ML/day) – this represents 64% of total mine inflow for the period.

Compared with the previous longwall, the total mine inflow increased by 23% and the inflow in Area 3B increased by 36%.

Seepage losses from Avon Dam have been estimated by regional and local scale numerical models to be in the range 0.09 to 0.69 ML/day as at the end of Longwall 17.

Longwall 17 passed beneath, or within 400m of, Swamps 14, 23, 149 and 35a.

  • A Level 3 TARP for shallow groundwater remains in place at Swamp 14 from previous Longwalls.
  • Shallow groundwater at Swamp 23 has been increased to a Level 3 TARP.
  • Soil Moisture at Swamp 14 has been increased to a Level 3 TARP.

Reduction in aquatic habitat for over 2 years at Donalds Castle Creek and WC21 constitutes a Level 3 TARP trigger.

In summary — we are losing loads of water into the mine due to subsidence effects. Endangered Upland Swamps are being drained dry by this mining, reducing their ability to act as filters and holders of water in the ecosystem. Lastly, Donalds Castle Creek is being trashed and the aquatic life there is dying.

Stay tuned for update #3!

If you’re super keen and want to read the report yourself, you can find it here.

Protect Our Water Alliance

WATCH POWATalks #1 – The Essential Importance of Upland Swamps, with Dr Tanya Mason

Did you know? Coastal upland swamps are linchpins in essential ecosystem functions and biodiversity conservation. Dr Tanya Mason talks in this presentation about essential importance of upland swamps to the Sydney-Illawarra Water catchments. They capture and store rainwater, then release water slowly as base flow in dry periods. They level out storm hydrographs and extract excess nutrients in turn supporting and protecting Sydney’s potable water supply. Swamps capture large amounts of carbon through the accumulation of humus and peat and support unique biodiversity.

Long-wall mining dries out and reduces the biodiversity of upland swamps. There is no evidence that swamps ever recover. There are no known methods of rehabilitation. The best way to protect these crucial water capturing ecosystems is to stop long-wall mining.

ABOUT POWAtalks:
A series of bite-sized talks with leading researchers on the wonders of the Greater Sydney water catchment and why it’s worth protecting.

We acknowledge the land that we live, work and join together to protect is stolen land. We pay our respects to elders past and present, and stand in solidarity with Dharawal, Yuin, Wodi Wodi and all First Nations people fighting for justice and self-determination.