Rivers SOS meeting above Cataract Gorge, Douglas Park

The Rivers SOS group met at Caroline's place at Douglas Park, for our quarterly meeting, in May 2009.

Here are four images of the group, just getting the meeting under way.
Taken from the back end of the room.

From the top end of the room (with light behind me).
Here is a group photo of the Rivers SOS meeting, taken after our meeting adjourned.
It was good to be joined by a number of Environmental Studies students.
Caroline is very proud of the sign writing.
(Click to read the words)

After dinner (and a very fine dinner it was), we were entertained by two very fine musicians, Mirabai Peart (who has been a member of the Rivers SOS group for some time) and Mahesh Radhakrishnan. They play together in "Tapestries of Sound"

Mahesh sings and plays guitar, and Mirabai is a very fine violin player.

Here Mahesh is playing a Thamboura.After the music, we had an informal party.

Next morning, the resident Swamp Wallaby was up nice and early
tasting the delights of Caroline's vegetable garden.
This Wallaby has suffered some kind of injury, unfortunately.
After breakfast (his and ours) we went out to explore the local area.

We started with a quick look over the Cataract River Gorge.

Here is a zoom shot showing the river flowing below.

After the rain of the week before, there was a good flow happening.While walking back I noticed this plant, which I think is a Crowea exalata.
Then we drove over to the West Cliff Colliery.
I could not believe their "Zero Harm" slogan. Can you?

Then we went to "Marhnyes Hole", below Appin.
This is on the Georges River.

Here, Julie is explaining the damage which occurred after subsidence caused by BHP longwall mines. There has been much "remediation" work in this area. And, after a week of rain, the river was flowing reasonably well. Neville and Amanda are looking on.We hope to meet again, next time, at Stroud, to find out more about the efforts of the locals to save Mammy Johnson's River.
Neville ("Chappy") Williams is from Lake Cowal, in western NSW, where Barrick Gold's mine is destroying the lake, with the support of the NSW Government.

The future of Water is Black - Black as Coal

The future of water is black - Black as coal.

Longwall Mining under rivers and aquifers is totally unsustainable, and against the best interests of society as we know it.
Humans have not evolved to drink coal – we need water.

What is Longwall Mining?
Longwall Mining is an underground mining technique using a huge rotary cutter (“shearer”), on a rail system, which extracts coal from a seam in continuous “faces” up to 300 metres wide. Each “panel” of removed coal may be as long as 2 kilometres. The height of the “shearer” is adjusted to the coal seam being extracted, but in the Illawarra region it averages approximately 2-3 metres high.

Longwall Mining machine, with "shearer" and rails.

Photo: - Coal Leader

In effect it cuts out an underground “room” as wide as 3 football fields are long, and extending for 2 kilometres in length. That is for each single panel. Panels are normally laid out in series, separated by walls of coal, known as “chain pillars”, which vary in thickness from 20 to 50 metres wide.

As mining progresses, the roof of the excavated area is allowed to collapse into the void (known as a “goaf”) behind where the shearer has been working. A collapse zone is formed above the extracted area. Above the collapse zone is a fractured zone where the permeability is increased to a lesser extent than in the collapse zone. Above this level, the surface strata will crack as a result of bending strains, with the cracks varying in size according to the level of strain, thickness of the overlying rock stratum and frequency of natural joints or planes of weakness the strata (Holla and Barclay 2000). The principal surface impact of underground coal mining is subsidence (lowering of the surface above areas that are mined).

Diagram of Longwall Mining - BHP.

(Click to enlarge - there is a tiny figure of a miner there - for scale).

The following notes have been extracted from the NSW Scientific Committee’s declaration of Longwall Mining as a Key Threatening Process under Schedule 3 of the NSW Threatened Species Conservation Act 1995.

1. Longwall mining occurs in the Northern, Southern and Western Coalfields of NSW. The Northern Coalfields are centred on the Newcastle-Hunter region. The Southern Coalfield lies principally beneath the Woronora, Nepean and Georges River catchments approximately 80-120 km SSW of Sydney. Coalmines in the Western Coalfield occur along the western margin of the Sydney Basin. Virtually all coal mining in the Southern and Western Coalfields is underground mining.

2. Longwall mining involves removing a panel of coal by working a face of up to 300 m in width and up to two km long. Longwall panels are laid side by side with coal pillars, referred to as "chain pillars" separating the adjacent panels. Chain pillars generally vary in width from 20-50 m wide (Holla and Barclay 2000). The roof of the working face is temporarily held up by supports that are repositioned as the mine face advances (Karaman et al. 2001). The roof immediately above the coal seam then collapses into the void (also known as the goaf) and a collapse zone is formed above the extracted area. This zone is highly fractured and permeable and normally extends above the seam to a height of five times the extracted seam thickness (typical extracted seam thickness is approximately 2-3.5 m) (ACARP 2002). Above the collapse zone is a fractured zone where the permeability is increased to a lesser extent than in the collapse zone. The fractured zone extends to a height above the seam of approximately 20 times the seam thickness, though in weaker strata this can be as high as 30 times the seam thickness (ACARP 2002). Above this level, the surface strata will crack as a result of bending strains, with the cracks varying in size according to the level of strain, thickness of the overlying rock stratum and frequency of natural joints or planes of weakness in the strata (Holla and Barclay 2000).

3. The principal surface impact of underground coal mining is subsidence (lowering of the surface above areas that are mined)

Damage to some creek systems in the Hunter Valley has been associated with subsidence due to longwall mining. Affected creeks include Eui Creek, Wambo Creek, Bowmans Creek, Fishery Creek and Black Creek. Damage has occurred as a result of loss of stability, with consequent release of sediment into the downstream environment, loss of stream flow, death of fringing vegetation, and release of iron rich and occasionally highly acidic leachate. In the Southern Coalfields substantial surface cracking has occurred in watercourses within the Upper Nepean, Avon, Cordeaux, Cataract, Bargo, Georges and Woronora catchments, including Flying Fox Creek, Wongawilli Creek, Native Dog Creek and Waratah Rivulet. The usual sequence of events has been subsidence-induced cracking within the streambed, followed by significant dewatering of permanent pools and in some cases complete absence of surface flow.

Subsidence associated with longwall mining has contributed to adverse effects (see below) on upland swamps. These effects have been examined in most detail on the Woronora Plateau (e.g. Young 1982, Gibbins 2003, Sydney Catchment Authority, in lit.), although functionally similar swamps exist in the Blue Mountains and on Newnes Plateau and are likely to be affected by the same processes. These swamps occur in the headwaters of the Woronora River and O'Hares Creek, both major tributaries of the Georges River, as well as major tributaries of the Nepean River, including the Cataract and Cordeaux Rivers. The swamps are exceptionally species rich with up to 70 plant species in 15 m2 (Keith and Myerscough 1993) and are habitats of particular conservation significance for their biota.

Flora and fauna may also be affected by activities associated with longwall mining in addition to the direct impacts of subsidence. These activities include clearing of native vegetation and removal of bush rock for surface facilities such as roads and coal wash emplacement and discharge of mine water into swamps and streams. Weed invasion, erosion and siltation may occur following vegetation clearing or enrichment by mine water.

Source: “Alteration of habitat following subsidence due to longwall mining as a KEY THREATENING PROCESS” NSW Scientific Committee
http://www.nationalparks.nsw.gov.au/npws.nsf/Content/longwall_mining_ktp

*** *** *** *** ***

What has happened since this declaration was published in 2005? Business as usual, in the mining industry, that's what.

The Dept of Environment and Climate Change (formerly DEC) has done the right thing (in making this declaration), but it is an appalling indictment of the decision makers in the NSW Government, and particularly the Mining Department and the Department of Planning, that they have allowed, indeed promoted, the use of these disastrous mining techniques under the Rivers which are the catchment for Sydney's water supply.

When the estimated 91% of the Illawarra Catchment has been undermined (estimated at some 20 years), what will Sydney do for water, then?

This map shows coal leases under the Illawarra Catchment 5 dams and rivers (Source: NSW Dept of Planning)

The DECC as a "Toothless Tiger".

Don't get me wrong, I support what they have written. But have they really exercised their full powers under the Threatened Species Act to actually prevent damage being incurred? Or have they just issued a "determination" - and left it at that?

*****

These are just some of the powers available to be exercised by DECC:

Interim Protection Order: Minister for the Environment may make an interim protection order for a period of up to two years over an area of land that has natural, scientific or cultural significance. The Minister may also make an interim protection order on land where the DEC Director-General intends to exercise functions relating to threatened species, critical habitat, or declared critical habitat under the NP&W or TSC Acts.

Stop Work Order: The Director-General of DEC may make a stop work order for a period of 40 days if an action is being, or is about to be carried out that would harm a threatened species, population or ecological community or it’s habitat. These orders can be renewed for 40-day periods as required.

*****

I haven't heard of any such powers being used to stop Longwall Mining by BHP Billiton (or their subsidiaries) or their international mining conglomerate allies, such as Metropolitan (Peabody Pacific Pty Ltd) or Gujarat NRE.

Have you?

Appin and Douglas Park visit - birds and Orchids

Further to my post of yesterday, about the deplorable state of the Georges River, let me now give you the good news.

There were Honeyeaters galore in the trees in Caroline's backyard. Her house sits atop the cliffs of the Cataract River Gorge. There are many Gum Trees along this top edge of the gorge, and, many other native trees and plants down below, in the gorge itself, of course.

The first birds I noticed were the Yellow-faced Honeyeaters, and Little Wattlebirds, and a family of Superb Fairy Wrens ("Blue Wrens"). We sat on the back deck and had a coffee, and listened to the Striated Pardalotes in the trees (always hard to see, while feeding on Lerps on the Eucalypt leaves.) Eastern Spinebills flipped past us, their noisy wing-beats attracting our attention.

Caroline and I then drove past Appin, and went for a walk to the Georges River. We heard Whipbirds calling in the dense shrubbery, as we approached the river. Once we got there, I noticed some frogs calling (but not many). But it was the birds which I was most conscious of. The Yellow-faces were still around, but there were other Honeyeaters, including the wonderfully bright Yellow-tufted Honeyeater, and the ever-present New Holland Honeyeaters. Those birds love Banksias and Grevilleas, both of which were in flower. I saw a female Golden Whistler, and a Grey Shrike Thrush. Two Black Ducks were swimming fitfully on the river, near some reeds.

The highlight for me was hearing (could I believe my ears?) what I thought sounded like the call of the Peaceful Dove. I have not seen this species in more than 20 years. And when I did, it was in central NSW, near Forbes and Dubbo. Could they be here, on the edge of the Sydney Basin?
Sure enough, after a few minutes of walking along the banks of the Georges River, I saw first one Dove, and then, a pair of them, sitting on a dead shrub across the river.These are lovely birds, with a quiet, non-aggressive nature, and a quiet voice. So much "nicer' than the aggressive New Holland HoneyeatersThis photo is not great, but it is diagnostic. You can just make out the blue eye ring, and the fine markings on the back and neck. Definitely not the introduced Turtle Dove.

As we walked back up to the road, I noticed a grassy glade, which looked promising for Greenhoods. Sure enough, there were many large leaves of a Greenhood in this moist soil. After looking around I found two open flowers of the Blunt Greenhood (Pterostylis curta).

It has a lovely shape from side on. And from the front view you can clearly see the diagnostic twisted labellum (tongue).Back at Caroline's a beautifully marked Pied Butcherbird landed in the tree, while I was on the phone talking to Bernie. I whispered to Caroline that the Butcherbird was here, and straight away she went and got some pieces of bread and put them on the deck railing. Clearly the Butcherbird has got Caroline trained, and it rewarded her by zooming straight in and grabbing a morsel immediately.This snatch and grab movement was so fast I only had a moment to point and shoot. No chance to adjust shutter settings, before the bird was off. But you can see what good plumage it had. Clearly an adult male.

Late in the afternoon, the Noisy Miners had moved in and chased away the other Honeyeaters. But they did not disturb a pair of King Parrots feeding on the Wild Tobacco Plant (Solanum mauritianum).

As a late-afternoon bonus, a family of 8 Yellow-tailed Black Cockatoos flew out of the Gorge, below us, and flew to a neighbouring Pine Tree. The younger members of the group then started their droning noises, while waiting for the adults to feed them. Who would be a parent?