IMPACTS OF LONGWALL COAL MINING ON THE …australiancoalalliance.com/Information/TEC LCM...

Total Environment Centrewww.tec.org.au

January 2007

PO Box A176

Sydney South. 1235

Ph: 02 9261 3437

Fax: 02 9261 3990

Email: [email protected]

IMPACTS OF LONGWALL COAL MINING ON THE ENVIRONMENT IN NEW SOUTH WALES

CONTENTS

Impacts of Longwall Coal Mining on the Environment in New South Wales Page 1

01 OVERVIEW 3

02 BACKGROUND 5

2.1 Definition 5

2.2 The Longwall Mining Industry in New South Wales 6

2.3 Longwall Mines & Production in New South Wales

2.4 Policy Framework for Longwall Mining 6

2.5 Longwall Mining as a Key Threatening Process 7

03 DAMAGE OCCURRING AS A RESULT OF LONGWALL MINING 9

3.1 Damage to the Environment 9

3.2 Southern Coalfield Impacts 11

3.3 Western Coalfield Impacts 13

3.4 Hunter Coalfield Impacts 15

3.5 Newcastle Coalfield Impacts 15

04 LONGWALL MINING IN WATER CATCHMENTS 17

05 OTHER EMERGING THREATS 19

5.1 Longwall Mining near National Parks 19

5.2 Longwall Mining under the Liverpool Plains 19

5.3 Longwall Top Coal Caving 20

06 REMEDIATION & MONITORING 21

6.1 Avoidance 21

6.2 Amelioration 22

6.3 Rehabilitation 22

6.4 Monitoring 23

07 KEY ISSUES AND RECOMMENDATIONS 24

7.1 The Approvals Process 24

7.2 Buffer Zones 26

7.3 Southern Coalfields Inquiry 27

08 APPENDIX – EDO ADVICE 27

EDO Drafting Instructions for Legislation on Longwall Mining

09 REFERENCES 35

Cover Image: The now dry riverbed of Waratah Rivulet, cracked,uplifted and drained by longwall mining in 2006. The Rivulet comprisesnearly 30% of the Woronora Dam catchment.

ABBREVIATIONS


ABC Australian Broadcasting Corporation

ACARP Australian Coal Association Research Program

AMCI American Metals and Coal International

BHPB Broken Hill Proprietary Billiton

CMA Catchment Management Authority

CoI Commission of Inquiry

CSIRO Commonwealth Scientific and Industrial Research Organisation

DEC Department of Environment and Conservation

DIPNR Department of Infrastructure Planning and Natural Resources

DLWC Department of Land and Water Conservation

DMR Department of Mineral Resources

DPI Department of Primary Industry

EDO Environmental Defenders Office

EIS Environmental Impact Statement

EP&A Environmental Planning and Assessment

KTP Key Threatening Process

LTCC Longwall Top Coal Caving

NPA National Parks Association

NSW New South Wales

SMP Subsidence Management Plan

TEC Total Environment Centre

01 OVERVIEW


Longwall mining is a form of underground coalmining that was introduced to Australia and theUnited States from Europe in the early 1960s. Itallows mining companies better access and vastlyimproved recovery rates than older methods ofunderground mining. It also results in far moredynamic land subsidence than the traditionalmethods. The effects of mine subsidence uponman-made infrastructure are well known.However, subsidence from longwall mining hashad, and continues to have, a dramatic effectupon the natural environment.

The practice of longwall mining first came underthe spotlight in 1974, when a dispute arosebetween the then Metropolitan Water Sewerageand Drainage Board and the Department of Minesover the proximity of longwall mining to the city’swater supply dams south of Sydney. An inquirywas established under Justice Reynolds into ‘CoalMining Under or In the Vicinity of the StoredWaters of the Nepean, Avon, Cordeaux, Cataractand Woronora Reservoirs’. Justice Reynolds madeseveral important findings, which were handeddown in 1977, including restriction zones arounddam walls and stored water. Reynold’s findingsalso identified an “angle of draw” at which certainlevels of subsidence are likely to occur (Reynolds1977).

In the early 1980s environment groups werealerted to numerous cliff falls on the NewnesPlateau, north of Lithgow, that had occurred as aresult of land subsidence due to longwall miningby nearby collieries. It later emerged thatCentennial Coal were also pumping 14 megalitresper day (about 14 Olympic swimming pools) ofmine effluent into the Wollangambe River,polluting it with a black muck that spreaddownstream.

By the 1990s, residents who lived along theCataract River southwest of Sydney reported largecracks in the riverbed above longwall panelsoperated by BHP (now BHP Billiton). Along withthe cracking, sections of the river downstreamfrom the cracking started to dry up, iron oxide

01Native Dog Creek: A large pool that would have been several metresdeep and a drought refuge for wildlife, has now been drained bylongwall mining. Note rock debris from destablisation of abutting cliff.


pollution stained parts of the river red, methanegas leaked to the surface, fish skeletons werediscovered and cliff falls occurred along the steepgorges running alongside the river. A 1998 courtjudgement found in favour of seven parties whohad sued BHP over the damage to the river – thecourt decided that 80% of the damage could beattributed to longwall coal mining.

Widespread cracking and draining of river andcreek beds and underground aquifers, cliff falls,the draining of rare swamps, fish kills, methanegas bubbling to the surface, iron oxide pollutionand the release of wastewater into river systemscontinue to occur across four coal mining regionsof New South Wales as a result of longwallmining. A very significant number of operationstake place in the Southern Coalfields in Sydney’swater supply catchment and longwall mining isalso proposed in the Central Coast’s water supplycatchment. Longwall mining poses a grave threatto the integrity of rivers and ecologicalcommunities in National Parks in the WesternCoalfield, while BHP Billiton’s Caroona project inthe Gunnedah Basin, currently in the explorationstage, threatens multiple levels of aquifers undersome of Australia’s richest agricultural land.

It is not disputed by any authority that subsidencedue to longwall mining can cause deformation ofground surfaces as well as cracking of valleyfloors and creeklines. This can affect natural waterflow regimes and water quality, depending onsuch factors as the width of the crack, riverbedsteepness, the riverbed material and the presenceof organic matter. Subsidence is known to occurup to 3km from a longwall panel.

In turn, these impacts can lead to the alteration ofspecies habitats and changes to the ecologicalfunction of communities (see Section 2.5,Longwall Mining as a Key threatening Process).Effects can be temporary or long-term. Whenwater flows are altered, there can be permanenteffects on the functioning of ecosystems inlocalised areas, which may be exacerbated indrought conditions.

Industry and government have responded to thissituation with monitoring and rehabilitationprograms. Although hailed by the industry assuccessful, past remediation efforts have failed.They have included concreting or grouting overcracks in riverbeds. However in many cases thecracks run hundreds of feet deep and have

reopened. In other cases cracking has occurredunder sandy riverbeds and cannot be detected. Insome cases the mining companies have had tobuy water from the water supply dams to providean environmental flow back to the damagedstream – but this is not a sustainable solution (andwastes water in times of drought).

The damage that was occurring to rivers fromlongwall mining forced changes in NSWGovernment policy through a new approvalsprocess that was introduced in 2004 (see 2.4,Policy Framework for Subsidence Management).This required mining companies to submit aSubsidence Management Plan (SMP) for newlongwall panels they were intending to mine.However, there is widespread concern that thenew approvals process is failing to protect theenvironment from subsidence damage.

SMP’s are being approved largely withoutamendments that ensure avoidance ofenvironmental impacts. While becoming moreaccurate in predicting the levels of subsidence,they offer no accurate assessment of the damagethat may occur to rivers and creeks. Currentgovernment policy responses are to monitor thedamage and try to fix it up later with unprovenremediation techniques. In cases where a river orcreek has suffered a loss of flow after mining, themining company will often try to shift the blame todrought conditions, even though streams inadjacent valleys are still flowing.

There are no protection zones mandated for riversbeing affected by longwall mining despitenumerous reports by government agencies andindependent bodies recommending such a policy.This could simply be implemented through abuffer zone around rivers and streams. The miningindustry continues to resist the concept of aprotection zone arguing that it is unnecessary andthat the viability of their longwall mines would beunder threat.

In November 2006 the Total Environment Centre(TEC) instructed The Environmental Defender’sOffice (EDO) to prepare drafting instructions forlegislation in relation to longwall mining includingthe establishment of a 1km buffer zone aroundrivers and creeks (see Appendix).

02 BACKGROUND


2.1 Definition

Longwall mining is a form of underground coalmining where ‘panels’ of coal are mined side byside separated by narrow ‘pillars’ of rock that actas supports. A long wall panel can be up to 4kmlong, 250-400m wide and 1-2m thick. Chocks arethen placed lines of up to 400 m in length tosupport the roof. Coal is cut by a machine called ashearer that moves along the length of the face infront of the chocks, disintegrating the coal, whichis then taken by a series of conveyors to thesurface.

As coal is removed, the chocks are moved intothe newly created cavity. As the longwallprogresses through the seam, the cavity behindthe longwall, known as the goaf, increases andeventually collapses under the weight of theoverlying strata. This collapsing can causeconsiderable surface subsidence that may damagethe environment and human infrastructure.

For the industry, the advantage of longwall mininglies in increased recovery rates of about 60percent over the more traditional bord and pillarmethod. Subsidence is largely immediate, most ofit occurring within two months. Theoretically, thisallows for better planning and more accountabilityby the mining companies. (University ofWollongong)

2.2 The Longwall Mining Industry in New

South Wales

Longwall mining in NSW began in 1962. In1983/84 it accounted for 11% of the state’s rawcoal production. This had increased to 36% by1993/94 and stood at 29% in 2003/04.

In 2003/04, there were 17 longwall coal minesoperating in NSW with several others proposed orabout to commence operating. Some minescombine a mixture of longwall and open cutmethods. The NSW coal industry predicts that by2013 about half of its production will come fromnew mines or extensions to existing mines.

The underground coal mining industry currentlyemploys about 5 000 people in NSW. Longwallmining accounts for approximately 89% of rawcoal obtained from underground miningoperations. About 72% of all coal produced inNSW is exported with 23% being used fordomestic power generation and the rest in steelmaking and other domestic industries such as -cement manufacturing.

Nearly all of the coal mined in NSW lies within theSydney-Gunnedah Basin and in the five definedcoalfields of Gunnedah, Hunter, Newcastle,Western (in the Lithgow / Mudgee area) andSouthern (in the Campbelltown / Illawarra area).Virtually all coal mining in the Southern andWestern coalfields is underground.

In recent times, mine ownership in the NSW coalindustry has followed a global trend to becomemore concentrated. The three major longwallplayers in NSW are BHP Billiton, Centennial andXstrata.

The NSW Government benefits from the coalindustry through mining royalties. The revenue

02


raised by these royalties has risen sharply in thelast few years as the international coal market hasboomed. The current royalty rates for undergroundmining stand at 5% for mines deeper than 400mor 6% for mines at less than this depth (MiningRegulation 2003). The NSW Government raised$354 million from coal mining royalties in the2004/05 financial year (DPI 2004/05). Royaltiespaid by mining companies to the NSWGovernment remain confidential, but on March30th 2005 Minister for Mineral Resources, KerryHickey, told a parliamentary committee on 30/3/05that “estimated royalties for longwall mines in2002/3 were $602 million” (Rivers SOS).

2.3 Longwall Mines in New South Wales

17 longwall mines in New South Wales producedover 37 million tonnes of coal during the 2003/04financial year.

2.4 Policy Framework for Subsidence

Management

On March 1st 2004 the NSW Governmentenacted a new policy framework for themanagement of coal mining subsidence inresponse to concern in the community and fromenvironmental regulators. This section is asummary of this process taken from the

Department of Mineral Resources New ApprovalProcess for Management of Coal MiningSubsidence, 2003.

The key element of the revised process is that anapproved Subsidence Management Plan (SMP) isnow required wherever underground mining islikely to lead to subsidence. The requirement foran SMP arises through a new condition attachedto the mining leases of all new and existingunderground coal mines. All subsidenceassessment is controlled under this new approval.Preparation of an SMP and adherence to its termsis managed under the Mining Act 1992, includingenforcement powers.

The Director-General of the Department of MineralResources (DMR) determines applications forapproval of SMPs. Prior to this, an interagencyreview committee reviews all draft SMPs and

advises the Director-General on approvalconditions. The Committee also participates in theongoing monitoring of subsidence management.However, it is the Director-General alone whomakes the final decision as to whether an SMP isapproved or not.

Public consultation processes apply to thepreparation and lodgment of all draft SMPs.

Mine Coalfield Owner LW Prod (t)

Angus Place West Centennial 956 367Appin South BHBP 2 999 752Baal Bone West Centennial 1 858 985Beltana No 1 Hunter Xstrata 5 446 703Cumnock Hunter Xstrata 380 591Dartbrook Hunter Anglo 3 248 326Elouera South BHBP 1 814 579Glennies Creek Hunter AMCI 2 195 725Metropolitan South Excel 1 084 851Newstan Newcastle Centennial 3 147 562Southland Newcastle Southland 857 038Springvale West Centennial 2 056 062Tahmoor South Centennial 1 015 490Ulan West Xstrata 3 090 627United Hunter Xstrata 3 228 757West Cliff South BHBP 1 414 087West Wallsend Newcastle Xstrata 3 041 860

37 837 362

N.B. Numerous mines have opened or changed ownership and a number of mines have closed inthe two years since. (Source: Department of Primary Industries, New South Wales Coal IndustryProfile, 2005)


Applicants must advertise their intention todevelop a draft SMP, identify and consult with alldirectly affected landholders and local councils,and take their views into account. Applicants mustreadvertise when the draft SMP is finalised andsubmitted to DMR. Members of the communityare free to make submissions to DMR in itsconsideration of the draft SMP.

Subsidence and its impacts must be addressedwithin the EIS as part of the development consentprocess. The preparation and approval of an SMPwill is then required as a condition of consent.Environmental impact assessment fordevelopment consent and other approvals is takeninto account in the SMP application process. TheDMR will aim for the full integration of conditionsimposed under the SMP, development consentand other approvals. Existing underground coalmines which already have development consentor operate under existing use rights will requirethe preparation and approval of an SMP beforebeginning new mining which causes subsidence.

The new approvals process applies to not justsecond workings but also first workingsassociated with secondary extraction panels suchas longwalls. An SMP is required if first workingsalone might lead to subsidence. SMPs are alsorequired before pillar extraction programs.

Part of this report reviews the success of the newregime.

2.5 Longwall Mining as a Key Threatening

Process

In July 2005 the ‘Alteration of habitat followingsubsidence due to longwall mining’ was listed bythe independent NSW Scientific Committee as akey threatening process under Schedule 3 of theThreatened Species Conservation Act 1995. A keythreatening process is defined as a process thatthreatens, or could threaten, the survival orevolutionary development of species, populationsor ecological communities, in particular if itadversely affects two or more threatened species,populations or ecological communities; or couldcause species, populations or ecologicalcommunities that are not currently threatened tobecome threatened.

The Scientific Committee recognised thatsubsidence due to longwall mining is the cause ofhabitat alteration, including cracks beneath astream or other water bodies, and that subsidencemay lead to “a temporary or permanent loss ofwater flows and could cause permanent changesto riparian community structure and composition”.

The Committee also noted that, “Species andecological communities that depend on aquaticand semi-aquatic habitats are particularly

Native Dog Creek, in Sydney’s water catchment area. Numerousriverbed cracks are caused by subsidence from underground longwallmining, resulting in complete loss of water and habitat.


susceptible to the impacts of subsidence.Subsidence can cause a decrease in water qualitysuch as reduced oxygen availability, encouragingbacterial growth, smothering native plants andanimals. Subsidence can also increase the amountof iron oxides in the water which directly affectsnative plants and animals”. (NSW ScientificCommittee, Alteration of habitat followingsubsidence due to longwall mining - keythreatening process declaration, 2005)

Five endangered species, twenty-three vulnerablespecies and four endangered ecologicalcommunities were listed as likely to be subjectedto alteration of habitat as a result of longwallmining. A further eleven species not currentlythreatened were also listed as “may becomethreatened” as a result of subsidence impacts.

A total of 4 threat abatement strategies wereidentified to help tackle this key threateningprocess. These were:

1 Establish management agreements with publicauthorities CMAs and land managers/owners.Continue DEC commitment to inter-agencycommittee for the review of SubsidenceManagement Plans with Dept. of PrimaryIndustries, Dept. of Lands, Dept of Planning &Dept of Natural Resources, to provide adviceon the protection of biodiversity.

2 Prepare Statement of Intent. Prepare astatement of intent to establish links betweenexisting regulation of clearing of nativevegetation and identifying strategies for theprotection of biodiversity.

3 Review and amend or adopt existing legislationand policies. Support the implementation of theMining Act 1992 and associated subsidencemanagement planing processes.

4 Review evidence of impacts. Determineimpacts of longwall mining and subsidence onbiodiversity with the aim to identifying prioritythreatened species, populations andendangered ecological communities impactedby this KTP.

03 DAMAGE OCCURRING AS A RESULT OF LONGWALL MINING


3.1 Damage to the Environment

The definition of successful [subsidence]prediction, therefore, depends upon theconsequences of predicting incorrectly. When thepossible cost of failure is small, the name of thegame is accuracy of prediction, and skating closeto the edge may be justified. When the cost islarge, then there is no game; safety andconservatism is paramount. (Holla and Barclay,Mine Subsidence in the Southern Coalfield, NSW,Australia, page 34, Department of MineralResources, 2000).

In this report we ask, ‘are current practices basedon conservatism?’ Chapters 3 and 4 are an outlineof the damage to date.

3.1.1 Subsidence

The amount of subsidence that results fromlongwall mining depends upon the width of alongwall panel (150-400m), the depth at whichmining takes place (in the Southern Coalfieldabout 500m), the height of the coal seam (2-4m),the width of the panels (20-50m) and a variety ofgeotechnical factors.

Following mining in an area, the gap left from theextraction of coal (approximately 3 metres whenmining the Bulli seam), collapses, forming what isknown as the ‘goaf’. After most longwalloperations in NSW this typically results inapproximately 1-2m of displacement at surfacelevel. As this collapse occurs, stress is placed onrock strata above, and uneven movement of thesurface and rocks below the surface results infracturing of the rock.

Areas of tensile and compressive strain occurnaturally in the environment, resulting, forexample, when mountains push down causingstrain on river valleys. Given that the area of least

resistance is upwards, into the air, a processreferred to as ‘upsidence’ may occur which maycompensate for some of the subsidence or mayincrease tensile strain at different points of thesurface.

Mining subsidence accelerates and exacerbates aprocess that may occur over thousands of yearsinto a few short weeks or months with about 80%of subsidence occurring within 2 months oflongwall mining.

Impacts can manifest in the form of fracturing ofrivers and rock benches, rock falls and slumping.Cracking may occur in other parts of thelandscape but these are often hidden by soil andvegetation. It is generally accepted that steepergorge type environments are more highly affectedby subsidence than flatter areas due to greatervariation in compressive and tensile strains. (EcoLogical Australia, 2004)

3.1.2 Cracking and Fracturing

In areas where fracturing of the riverbed occursand the river is not connected to the naturalwatertable, a net loss of surface water to theunderlying groundwater occurs. (Hawkesbury-Nepean River Management Forum, 2004)

The tensile and compressive strains that comeabout as a result of subsidence often result in thecracking or fracturing of surface rock. This has thegreatest impact when occurring alongwatercourses or rock shelves. Fractures range insize from up to around 50cm. Such fracturing mayresult in water loss, gas release and rock falls, aswell as impacting upon manmade infrastructure.Cracking may also take place when soil separatesas a result of subsidence. Monitoring indicatesthis to be a fairly rare occurrence, howeverevidence of cracking is likely to be less notable

03


due to vegetation cover and filling of cracksthrough erosive processes. (Ecological Australia,2004)

3.1.3 Rock and Cliff Falls

Rock benches and overhangs, common acrossareas of Hawkesbury Sandstone where muchlongwall mining takes place, are susceptible tofracturing in the same way as riverbeds. Cliff fallshave occurred in such places as the NewnesPlateau, the Illawarra Escarpment and the CataractRiver. These may have a dramatic impact uponcliff line ecology and sites of Aboriginalsignificance. (Eco Logical Australia, 2004)

3.1.4 Water Loss

Subsidence-induced cracks occurring beneath astream or other surface water body may result inthe loss of water to near-surface groundwaterflows. If the water body is located in an areawhere the coal seam is less than approximately100-120 m below the surface, longwall mining cancause the water body to lose flow permanently. Ifthe coal seam is deeper than approximately 150 m,the water loss may be temporary unless the areais affected by severe geological disturbances suchas strong faulting. It is claimed that in the majorityof cases, surface waters lost to the sub-surfacere-emerge downstream. The ability of the waterbody to recover is dependent on the width of thecrack, the surface gradient, the substratecomposition and the presence of organic matter.An already-reduced flow rate due to droughtconditions or an upstream dam or weir willincrease the impact of water loss throughcracking.

The potential for closure of surface cracks isimproved at sites with a low surface gradientalthough even temporary cracking, leading to lossof flow, may have long-term effects on ecologicalfunction in localised areas. The steeper thegradient, the more likely that any solidstransported by water flow will be moveddownstream allowing the void to remain open andthe potential loss of flows to the subsurface tocontinue. A lack of thick alluvium in the streambedmay also prolong stream dewatering (by at least13 years in one case study in West Virginia).Impacts on the flows of ephemeral creeks arelikely to be greater than those on permanentcreeks. Cracking and subsequent water loss canresult in permanent changes to ripariancommunity structure and composition. (NSWScientific Committee, Alteration of habitat

following subsidence due to longwall mining - keythreatening process declaration, 2005)

Upland swamps, particularly on the NewnesPlateau and in the Southern catchments, have alsosuffered damage from water losses and resultedin the Newnes Plateau Shrub Swamp being listedas an endangered ecological community.

Changes to drainage and moisture conditions insome swamps, including the largest example ofthe community, are caused by damming ofswamp watercourses; roading across theswamps; sedimentation and erosion associatedwith roadways, quarries, mines and plantationharvesting within swamp catchments; anddisposal of waste water from underground coalmines. These changes pose threats to thepersistence and integrity of Newnes PlateauShrub Swamp, given the crucial roles of waterregimes in the composition, structure and functionof the community. Alteration to the natural flowregimes of rivers and streams and their floodplainsand wetlands is listed as a Key ThreateningProcess under the Threatened SpeciesConservation Act (1995) – NSW ScientificCommittee, Newnes Plateau Shrub Swamp in theSydney Basin Bioregion - endangered ecologicalcommunity listing – final determination, NSWScientific Committee, 2005)

3.1.5 Water Quality

When water is redirected as a result of fracturingor cracking, it interacts with the varioussubsurface strata that it comes in contact with.Within such strata there is an array of compoundsand sediments that may be dissolved by thewater, eventually ‘leaching’ back into the drainagelines. Iron oxides are a typical material in manyNew South Wales creeks undermined by longwallmining. These have an impact on water chemistryand aesthetics as well as increasing the level ofsuspended solids resulting in a significantreduction in the quality of water and aquatichabitat. (Eco Logical Australia, 2004)

3.1.6 Gas

Fracturing of rock strata may result in gas release.Such gas is associated with near surface geology,not the coal seam being mined. The gases arepredominantly carbon based (C4 and C6) andmethane. Impacts may include localisedalterations to water chemistry, soil heating anddieback of riparian vegetation, as occurred in thenearby Cataract River during the 1990s. (EcoLogical Australia, 2004)


3.1.7 Wastewater

Large amounts of water are used in bothunderground and above ground longwall miningoperations. In addition, runoff from the colliery andwashery sites can include coal dust, oils etc. Thecoal washery is designed to recycle the bulk ofthe water in use. However, the water in use hasan inherent level of salinity that is graduallyincreased as a result of evaporation.

When required, water is discharged from anumber of collieries to maintain environmentalflows in the rivers and creeks to offset water lossthrough fracturing of the riverbed. The waterutilised for mining operations has chemicalcharacteristics that do not meet minimumrequirements for discharge into the river system.In order to meet licence standards and maintainenvironmental flows, mines mix this water withpotable town water or water from storage dams,which, (given the current drought conditions andassociated water restrictions), can be seen as apoor use of a valuable resource.

In the case of the Lower Cataract River, where itwas cracked below the Broughtons Pass Weir, thecurrent environmental flow releases (purchased byBHP from the Sydney Catchment Authority (SCA)and released from Broughtons Pass Weir) are not

enough to keep the river flowing or to maintainacceptable water quality. (Ecological Australia,2004)

3.1.8 Slumping

Slumping generally occurs on steeper slopeswhen unconsolidated surface material movesdown slope. This increases localised soil erosionand can result in higher levels of sedimentation,loss of vegetation and reduction of water quality.(Eco Logical Australia, 2004)

3.2 Southern Coalfield Impacts

3.2.1 Lower Cataract River – Tower

Colliery now absorbed by Douglas Colliery

(BHP Billiton)

Nine longwall panels were mined directly underthe Lower Cataract from 1988 to 2000. Localresidents began to report damage to the river in1994. Water had drained away, hundreds of cracksin the riverbed were revealed, as were theskeletons of fish up to 1m in length. From 1996onwards, large amounts of methane gas beganventing in spots in the riverbed. At its height,sections of the river appeared to be boiling andthe gas could be set alight.

The dam wall of Broughtons Pass Weir, controlling20% of Sydney’s water supply, was also crackedin four places and leaked across its face. A pumphouse adjoining the weir was also damaged. TheNepean Tunnel and the Upper Canal were crackedand the extent of water loss was unknown. (TEC& Colong Foundation, 2001)

In its submission to the Dendrobium Commissionof Inquiry in 2001, the NSW Department of Landand Water Conservation estimated that theCataract River had lost 50% of its flow downcracks (DLWC).

According to a report by DIPNR’s Hawkesbury-Nepean River Management Forum,“Investigations confirmed that the loss of waterwas primarily attributable to long-wall mining. BHPundertook rehabilitation by grouting the crackedstreambed at key sites to reduce the loss ofwater” (Hawkesbury-Nepean River ManagementForum, 2004). The current environmental flowreleases of 1.7 ML/day in the Cataract Riverreleased from Broughtons Pass Weir are notenough to keep the river flowing or to maintainacceptable water quality.

In August 2006, Primary Industry Minister IanMacdonald approved the Appin 3 proposal by BHP

Cataract River: crack caused by longwall mining.


Billiton. This will see three longwall panels comewithin 60m of the Cataract River. Minutes of theSMP Interagency Review Committee meetingheld on August 2nd 2006 show that anindependent consultant recommended that miningcome no closer than 350m to the Cataract River.

3.2.2 Upper Georges River – Appin

Colliery & West Cliff Colliery (BHP Billiton)

Surface cracking of the riverbed in the upperreaches of the Georges River, near Appin, hasoccurred due to the subsidence that has resultedfrom the longwall coal mining. This surfacecracking has caused loss of river water andconsequently the loss of instream habitats,instream biota and degraded water quality.Changes to the local groundwater movement haveoccurred, as has damage to the surroundinglandscape – The Hon Ian Macdonald, Minister forNatural Resources, 1st July 2003

The Upper Georges River catchment is affectedby mining at both the Appin and West CliffCollieries. In 2000 Jutt’s Crossing on the GeorgesRiver at Appin cracked and water in rock poolsdisappeared. Further cracking to the River wasreported in 2001. In 2002 Marhnyes Hole, apopular swimming hole near Appin, cracked andwater disappeared. Rock fall collapses forced thetemporary closure of the swimming hole to thepublic on safety grounds.

Through licences issued by DEC, BHPB ispermitted to discharge polluted water, high in pHand salinity from the mines, primarily over theBrennans Creek Dam Spillway. Part of BrennansCreek was redirected to allow for modifieddrainage resulting from coal waste emplacementareas for Appin, West Cliff and Dendrobiummines. Discharges from the Appin town watersupply are also be used to maintain environmentalflow. BHPB pumps 1.5 - 2 megalitres of water perday back into the river system. The water comesfrom the Appin town water supply, supplied bythe Cataract Dam, and includes 1% recycledwater from the Appin mine.

3.2.3 Stokes Creek – Appin Colliery and

West Cliff Colliery (BHP Billiton)

Stokes Creek was undermined between 1990 and1999. Surveys in 2004 identified substantial areaswhere water levels had dropped considerably aswell as ongoing problems with the leaching ofoxides. No such drops in water level wereobserved in areas that had not been undermined(Eco Logical Australia, 2004).

BHPB indicated that remediation work would becarried out but it appears that this has not yettaken place (NPA Macarthur Branch 2005).

3.2.4 Bargo River – Tahmoor Colliery

(Centennial Coal)

Longwall damage to the Bargo River in 1994 wasamong the first to be reported in the SouthernCoalfields. In 2002 a 2km section of the BargoRiver near Tahmoor was reported as beingcompletely dry and large cracks were found in theriverbed. The Tahmoor Colliery is pumping anaverage of 5 tonnes of salt per day from itsworkings into the river. Longwalls proposed in2006 would come within 230m of cliff lines alongthe Bargo River. Wollondilly Council has indicatedits intention to petition the NSW Governmentagainst longwall mining near the Bargo Gorge. Thesection of the River affected by longwall mining islisted as an Indicative Place on the Register of theNational Estate.

The Bargo River catchment is one of theMacarthur Region’s most significant natural andcultural features, and one of the few substantialbushland areas around Sydney that is notprotected in a National Park or MetropolitanCatchment Area (National Parks Association,1999).

3.2.5 Upper Nepean River – Appin Colliery

(BHP Billiton)

Minister Macdonald approved four new longwallsforming part of BHPB’s Douglas Area 7 Projectwithout modification in November 2006. Thesewill come within 180m of the Nepean River. In theyear 2000 the bridge where the F5 Freewaycrosses the Nepean at Douglas Park had to bestrengthened and repaired when mining camewithin 600m as the hinge joints on the bridgewere opening up. Mining was halted at that point.With a sandy riverbed, it will be more difficult todetect fracturing and implement remediationefforts.

3.2.6 Flying Fox Creek, Wongawilli Creek

& Native Dog Creek – Dendrobium Mine &

Elouera Mines (BHP Billiton)

The NSW Scientific Committee’s key threateningprocess declaration states that these creeks haveall suffered from subsidence-induced crackingwithin the streambed, followed by significantdewatering of permanent pools and in some casescomplete absence of surface flow. In the case ofWongawilli Creek, upland swamps have beendrained and pollution has also occurred


downstream. All are located in the SouthernCatchments feeding the Avon and CordeauxDams. (NSW Scientific Committee, 2005)

3.2.7 Waratah Rivulet – Metropolitan

Colliery (recently acquired by Peabody

Energy from Excel Coal)

Waratah Rivulet is located just to the west ofHelensburgh and flows into the Woronora Damfrom the south. Along with its tributaries, it makesup about 29% of the Dam catchment. In 1999 theHealthy Rivers Commission described thecondition of the Woronora catchment upstream ofthe dam, as largely pristine. The Dam providesboth the Sutherland Shire and Helensburgh withdrinking water. Metropolitan Colliery operatesunder the Woronora Special Area. Recentunderground operations have taken place and stillare taking place directly below the Waratah Rivuletand its catchment area.

In September 2006, the TEC and ColongFoundation were informed that serious damage tothe Waratah Rivulet had taken place. Aninspection was organised through the SCA thatcovered the length of the Rivulet that flows overthe longwall panels. The Rivulet had ceased toflow for much of its length. The sandstonestreambed is cracked in a way typical of thatcaused by longwall mining in the SouthernCoalfield. SCA officers indicated that at one seriesof pools, water levels had dropped about 3m.Anecdotal evidence suggests the Rivulet hasceased to pass over places never previouslyknown to have stopped flowing.

The watercourse has also tilted to the east as aresult of the subsidence and upsidence. Iron oxidepollution has also occurred. Attempts atremediation have failed with a distinctly differentcoloured sand having washed out of cracks andnow sitting on the dry riverbed or in pools. Alsoundermined was Flat Rock Swamp at thesouthernmost extremity of the longwall panels. Itis believed to be the main source of waterrecharge for the Waratah Rivulet. It is highly likelythat the swamp has been drained and tilted.

The SMP for the next series of longwall panelssurprisingly states that there has been nosignificant impact upon net flow or water quality.Peabody intends to extract a further 27 longwallpanels that will run under the Rivulet and finishunder the Woronora Dam storage area itself. Thepanels responsible for the current damage arerelatively small longwalls with a width of 158m.

3.3 Western Coalfield Impacts

3.3.1 Goulburn River & Moolarben Creek –

Moolarben Coal Project (Felix Resources),

Ulan Mine (Xstrata Coal)

The Moolarben Coal Project is a proposal thatconstitutes three open cut mines and 24 longwallpanels at the top of the Goulburn Rivercatchment. The longwall panels are proposed tocome within 50-200m of the Goulburn River. Thesite is bounded by the Goulburn River to the northand west, and Goulburn River National Park to theeast. Mining will threaten the fragile sandstonecliffs and gorges along the Goulburn River,including the well-known Great Dripping Wall, andthe groundwater system with numerousunderground springs feeding the river. The areafeatures important aboriginal cultural sites(including cave paintings). The company are alsoproposing three open cut mines in the MoolarbenValley.

The Wilpinjong Open Cut Mine (Peabody CoalLimited) was recently granted a DA to open cutmine 28 square kilometres of the valley, whileUlan Coal Mines (Xstrata) has been granteddevelopment permission to expand its open cutand longwall operations, including a 400m widelongwall – the largest in Australia. Ulan Coal Minecurrently produces over 11 million litres of excessmine water per day and discharges up to 5ML/dayof salt-affected water into Ulan Creek. Minesubsidence and dewatering of the undergroundmine creates a regional ‘draw down’ affectcausing interference to surrounding aquifers andthe base flow of the Goulburn River.

3.3.2 Wollangambe River & Farmers

Creek – Clarence Colliery (Centennial Coal)

Farmers Creek suffers from cracking and had tobe paved with cement where it runs throughLithgow. Pumpouts of 14 megalitres a day fromCentennial mine into Farmers Creek and theWollangambe River have badly polluted the waterwith iron and manganese being deposited on thecreekbed. Farmers Creek supplies the town ofLithgow with its drinking water and theWollangambe River forms part of the Sydneycatchment and runs through the Blue MountainsWorld Heritage Area.

In 1999, Centennial Coal stated that to do nothingabout Clarence Colliery’s pollution of theWollangambe River “is not an option that isacceptable to Centennial, Department of Land andWater Conservation, Lithgow City Council, or the


Environment Protection Authority”. TheEnvironmental Impact Statement for a greatlyexpanded Clarence Colliery that followed,however, did not propose any solutions to theWollangambe pollution problem. (ColongFoundation for Wilderness)

Longwall mining under the Newnes Plateau andthe draining of swamps and aquifers as a resultplayed a significant role in the listing of NewnesPlateau Shrub Swamp in the Sydney BasinBioregion as an endangered ecological communityin 2005. Hundreds of cliff collapses have occurredon the Plateau as a result of longwall mining:

The Newnes plateau is underlain by extractablecoal seams at varying depths, with undergroundlongwall mining occurring, or proposed to occur,beneath the majority of the swamps. Subsidenceof the land surface, and associated fracturing ofbedrock between the coal seam and the surface,occurs after longwall mining, and this may changethe hydrology of catchments and swamps theycontain. Specifically, the conversion of perchedwater table flows into subsurface flows throughmine-related voids may significantly alter thewater balance of upland swamps (Young and Wray2000). Changes to surface morphology within ornear the swamps as a result of mine subsidencemay also create nick points which become thefocus of severe and rapid erosion (Young 1982).These changes pose threats to the persistenceand integrity of, the community. Alteration ofhabitat following subsidence due to longwallmining is listed as a Key Threatening Processunder the Threatened Species Conservation Act(1995) – NSW Scientific Committee, NewnesPlateau Shrub Swamp in the Sydney BasinBioregion - endangered ecological communitylisting – final determination, NSW ScientificCommittee, 2005)

3.3.3 Cox’s River – Angus Place,

Springvale & Clarence Collieries

(Centennial Coal)

The Cox’s River catchment is affected bynumerous longwall mines operating in the top ofits catchment. Hanging swamps have beendamaged and decreasing environmental flowshave been recorded. There is also rising salinityand alkalinity due to mine dewatering. LongSwamp, at the source of Cox’s River, is drying,probably as a result of longwall mining.

In 2002 the CSIRO reported that:

Although there have been some efforts atremediation, there is considerable contaminationof streams within the Cox’s River catchment fromcoal stockpiles, coal mining wastes and aciddraining from operating and derelict mines. Twooperating collieries within the vicinity, Angus Placeand Clarence, are discharging good-quality minewater into other catchments at the same time thatDelta Electricity is extracting potable water fromthe Cox’s catchment and 8,000 megalitres perannum from the Fish River Reservoir. Somerationalisation of this water management wouldensure an adequate supply for Delta Electricityand environmental flows in the Cox’s River.(CSIRO, 2002)

3.3.4 Kangaroo Creek – Angus Place

(Centennial Coal)

The puncturing of two underground aquifers hasresulted in significant amounts of salinegroundwater flowing into the mine. CentennialCoal currently pumps 12 megalitres ofgroundwater per day from the mine. Up untilrecently, this water has been discharged (underDEC licence) into Kangaroo Creek, which lieswithin Sydney’s drinking water catchment. Arecently implemented water transfer system to

Cataract River: clean pool in 1975 Same pool in 2005. Lost water sometimes re-emerges polluted(turbidity and oxides) from flowing through underground strata.


the nearby Delta Electricity power stations hasreduced discharges to the Kangaroo Creek andWolgan River catchments down to 3.5-4megalitres per day. There are 5 main aquifers inthe rock strata above the mining area and it is thelower 2 of these that have been punctured.

Studies by the company have concluded that thelower two aquifers are not hydraulically connectedto those above them, “do not directly contributeto surface environmental flows, and do notsignificantly contribute to Sydney’s drinking watercatchment”. The upper aquifers are a vital sourceof water for the ecologically endangered NewnesPlateau Shrub Swamps (NSW Department ofPlanning, 2006) that are located above longwallsthat are currently being mined and a number ofwhich have been badly damaged by mines acrossthe coalfield.

3.4 Hunter Coalfield Impacts

3.4.1 Hunter River

While not undermined by longwall panels orthreatened by future longwall proposals, theHunter River suffers from the combined effects ofa number of mining operations (open cut andlongwall) in the catchment including pollution,salinity, river diversions and losses of environmentflows. The Goulburn River in the WesternCoalfield (see Section 3.3.1) is the Hunter’s largestand most westerly tributary.

3.5.2 Bowman’s Creek

In the 1980s Bowman’s Creek, near Singleton,had its bed cracked from underground mining,causing a total loss of water in some areas and anincrease in salinity where it started flowing againdownstream. Anecdotal evidence (Hunter ValleyMinewatch, Stateline, ABC, 30/7/04) describes theowner of a property in Ravensworth going to lookat his cattle and seeing that that the water thathad been flowing the day before had stopped.After walking up the creek, into the next-doorproperty, the owner found that the creek bed hadcracked and dropped, and flow has not returned tothis day.

3.4.3 South Wambo Creek – Hunter Coal

(Wollemi UGM)

Also impacted by open cut coal mining, SouthWambo creek was cracked and drained causingsurface water to enter underground workings(NSW Department Of Planning, 2002).

3.4.4 Glennies Creek, Eui Creek, Fishery

Creek, Black Creek & Foy Brook

All listed as being damaged, cracked and polluted(NSW Scientific Committee, Alteration of habitatfollowing subsidence due to longwall mining - keythreatening process declaration, 2005; and RiversSOS, NSW Rivers of Shame, 2006)

3.5 Newcastle Coalfield Impacts

3.5.1 Wyong River & Jilliby Creek –

Wyong Proposal (Kores)

In terms of longwall mining and the threats itposes to water supply catchments, the proposalto establish a longwall mine under the Dooralongand Yarramalong Valleys on the Central Coast isthe most contentious issue outside of the SydneyMetropolitan catchments. Both Wyong andGosford Councils have stated their opposition tomining in the catchment.

3.5.2 Diega Creek – West Wallsend

Colliery (Xstrata Coal)

Diega Creek is now the subject of a rehabilitationproject involving Xstrata, various governmentagencies and the local community. Cracks of up to10cm wide formed after longwall mining underthe creek between 1999 and 2005. Despite asignificant loss of water suffered by the creek,Xstrata stated that they only became aware of theproblem midway through 2006. The company alsoclaimed that grazing could have been acontributing factor to the loss of water. (ABCNews, Newcastle, 7/7/06)


Environmental Impacts of Longwall Mines in NSW

Mine

RegionO

wner

Cracking/Draining

Pollution/SalinityCliff/Rock Falls

Major River

Creek or StreamSupply Catchm

entN

ational Park/SCA

Tower

SouthernBHPB

YY

Ylow

er CataractM

etropolitan

West Cliff

SouthernBHPB

YY

Yupper Georges

AppinSouthern

BHPBcom

menced

comm

encedcom

menced

upper Cataract

AppinSouthern

BHPBY

Yupper Georges

Stokes Creek

Tahmoor

SouthernCentennial

YY

Bargo

Dendrobium /

Delta

(former Elouera)

SouthernBHPB

YY

YW

ongawilli Creek

Metropolitan

Delta

(former Elouera)

SouthernBHPB

YY

Native Dog Creek

Metropolitan

Metropolitan

SouthernPeabody

YY

YW

aratah RivuletM

etropolitan

Metropolitan

SouthernPeabody

YHacking

Camp Gully Creek

Royal

Moolarben

Western

Felixproposal

proposalproposal

GoulburnGoulburn River

UlanW

esternXstrata

YY

GoulburnUlan Creek

Goulburn River

ClarenceW

esternCentennial

YW

ollangambe

Farmers Creek

Metropolitan

Blue Mountains

Angus Place / Springvale

Western

CentennialY

YW

olgan & Cox's

numerous

Metropolitan

Wollem

i/Gardens of Stone

Baal BoneW

esternXstrata

YJew

's CreekM

etropolitanW

ollemi

numerous

HunterY

Hunternum

erous

Wollem

i UGMHunter

Hunter CoalY

HunterSouth W

ambo Creek

HunterY

YHunter

Bowm

ans Creek

Wyong Proposal

New

castleKores Australia

proposalproposal

proposalW

yongJilliby Creek

Central CoastJilliby SCA

West W

allsendN

ewcastle

XstrataY

YDiega Creek

Caroona ProposalGunnedah

BHPBexploration

explorationN

amoi (&

major aquifers)

04 LONGWALL MINING IN WATER CATCHMENTS


A number of operating longwall coal mines in theSouthern Coalfield and the Western Coalfieldoccur within the Sydney water catchment. Thesepristine catchments are also home to 30threatened animals and 26 threatened plants,including the Spotted-tail Quoll and contain theonly viable koala populations near Sydney. Thecatchments cradle significant rainforest and tall oldgrowth forests remnants, as well as uplandswamps of very high conservation significance.These catchments were recommended for WorldHeritage listing values in 1994 by the RoyalBotanic Gardens as part of the Blue Mountainsand surrounding plateaux nomination. (ColongFoundation)

There is also a proposal for longwall mining totake place in the Wyong catchment on the CentralCoast. Other towns, such us Lithgow andRichmond, also take their drinking water fromrivers subject to the effects of longwall miningupstream.

Mining in catchment areas poses one of thebiggest threats to the environment and watersupplies due to the potential for water quality andquantity to be compromised.

Five dams are located within the SouthernCoalfield supplying water to the Sydney region.The Nepean, Cordeaux and Cataract Dams supplySydney with about 20% of its drinking water viaProspect Reservoir. This water is taken from theUpper Nepean River via the Nepean Tunnel toBroughtons Pass Weir. From there it travels viathe Cataract Tunnel and Upper Canal to ProspectReservoir. The Avon Dam and also the NepeanDam supply the Illawarra region, while theWoronora Dam provides water to the SutherlandShire and the town of Helensburgh. TheMacarthur region takes its water from a filtration

plant at Broughtons Pass Weir. (SydneyCatchment Authority)

The past decade has seen an intensification ofmining in the immediate vicinity of the major riversin the Sydney catchment. Mining companies,mainly BHP, had avoided mining under the riversuntil the late 1980s and it was the damage to theCataract River that brought the issue to publicattention in the mid 1990s.

The Cataract Tunnel had longwall panels fromBHP’s Appin Mine extracted underneath itbetween 1997 and 1999. Greater shear stressfractures and cracks in the wall and roof of thetunnel were reported. An SMP for Longwall 409of the Appin mine was submitted in 2006. Theproposed longwall panel passes underneath theUpper Canal and below a wrought iron viaduct. Inthe 2003-04 financial year the SCA spent $5.58million on the Upper Canal; $2.13 million of thiswas for “extensive mining-related preventivework”. (Sydney Morning Herald 28/1/05)

In the case of the BHP Elouera Mine, whichundermined two creeks in the water supplycatchments, the longwalls were 185m wide at adepth of 340m. The damage to the creeksincluded extensive and intense cracking of theirrock beds and draining of all rock pools (small andlarge) in mined areas, where under normalunmined circumstances the affected streamswould be flowing (as was the case with similarcreeks in the vicinity not subject to mining). TheElouera Mine reported increased water inflow(225 megalitres a month) into the mine itself. Theloss of water is most serious in terms of thecatchments’ capacity to supply water, particularlyin drought years and the loss of catchmentintegrity and biota. (Colong Foundation 2001)

04


The issue of water loss and damage to thecatchment was highlighted at the 2001Commission of Inquiry into the proposedDendrobium Mine – which commenced operatingin 2004. In its submission, Sydney CatchmentAuthority said, “ There is evidence of pools beingdrained, reduce flows and a reduction in waterquality….a potential for cracking beneath swampsto drain a significant amount of water containedin the swamps. This could lead to drying ofswamps – adversely affecting their ecologicalintegrity but also reducing water flowsdownstream. Practical means of remediation aregenerally not available.” (30 July 2001)

The TEC and Colong Foundation also noted that,“in the shale geology of the metropolitancatchment and environs, the groundwater is eco-toxic, containing dissolved salts, dissolvedhydrogen sulphide which is toxic to aquatic life,low oxygen levels and elevated soluble ironlevels.” (TEC and Colong Foundation, 2001)

In 2001 the CSIRO conducted an audit for theSydney Catchment Authority. In regard to thedamage being inflicted upon the catchment areasby longwall mining, the audit claimed it would besome years before definitive trends arerecognised and benchmark data was absent.

The study also raised concerns over theenvironmental wellbeing of hanging swamps inthe Special Areas:

Another concern is that subsidence will result inthe loss of water and aquatic ecosystems fromhanging swamps in the Special Areas. A survey byBiosis (Selga Harrington 2001) has revealed someholes and cracks in Swamp 18 above the Eloueramine with accompanying desiccation and fallenvegetation. A subsequent inspection by staff ofBHP Billiton, SCA, Biosis and MSB was unable tofind unequivocal reasons for these features. Aswith Wongawilli Creek, there are no baseline dataand monitoring of this and other hanging swampsis to commence. (CSIRO, 2002)

It is apparent that the current managementresponse in the sensitive and importantcatchment lands is to monitor even thoughdamage is obvious and continuing. This is afundamental failure of the precautionary principle,with the protection regime taking second place tocoal extraction.

The CSIRO Audit also noted that in 1999 thereexisted less than optimal relations between theSCA and the relevant State Governmentdepartment (Department of Mineral Resources –DMR).

Without strong and effective protection measures,water supplies critical to Sydney and Wollongongwill suffer further longwall damage and becomemore polluted. The catchment is managed by theSydney Catchment Authority, which was createdin 1998 after a series of water contaminationincidents. The Catchment Authority has alegislative duty to preserve the ecological integrityof the area, but does not have any power toprevent mining. The new approvals process didgive the SCA a greater say in the regulation ofmines within the Special Areas but only advisorypowers, as the Director-General of the DPI is thesole authority who approves SMP applications.

The damage that took place in the Waratah Rivulet(see 3.2.7) in 2006 was the result of longwallpanels that pre-date the current approvals regime.In light of this, the further granting of an approvalof an SMP for four more longwall panels underthe Waratah Rivulet, without modification, is botha serious indictment on the SCA’s power toinfluence the Department of Mineral Resourcesand the integrity of the current approvals regime.

Other government rules and policies, such asSydney Catchment Regional Environmental Planand the Sydney Water Catchment ManagementAct 1998 state that development in catchmentsshould have only a “neutral or beneficial effect”on water quality and are being overridden by theMining Act 1992. The SCA appears powerless tohalt the damage to Sydney’s water supply.

05 OTHER EMERGING THREATS


5.1 Longwall Mining near National Parks

Longwall mining has taken and is taking place upto the boundaries of several National Parks,particularly in the Western and SouthernCoalfields. This has caused damage to naturalfeatures such as the cliffs and rock formations inthe Gardens of Stone National Park and poses athreat to places such as the Great Dripping Wall inthe Goulburn River National Park.

As part of the 1998 NSW Forest Agreements, thenew tenure of State Conservation Area (SCA) wascreated specifically to allow mining in areas wherelogging was prohibited. This has already hadadverse effects in Barrington Tops near PolblueSwamp, where ruby mining is taking place in theheadwaters of the Manning River.

Proposed longwall panels at the Tahmoor Collieryalso threaten the proposed Bargo National Park.

5.2 Longwall Mining under the Liverpool

Plains

In June 2006 the NSW Government granted coalexploration rights to a 350-square-kilometre areaof the Liverpool Plains in the Gunnedah Basin.BHP Billiton paid more than $100 million for this.Near Quirindi in northwest NSW, the explorationsite is in the centre of the Liverpool Plains wellknown for their rich alluvial soils and vastunderground water resources.

The coal seam under the Liverpool Plains lies at adepth of 400m below the surface meaning thatlongwall mining would be the most likely methodof extraction. There are concerns among farmersgroups that subsidence on the Liverpool Plains willdramatically alter drainage patterns andcompromise the farming land. The NSWGovernment recently made dramatic cuts to

farmers’ groundwater entitlements.

Longwall mining has never taken place under suchdeep alluvial soils, which are up to 80m in places.Along with the farmers, towns along the NamoiRiver rely upon the underground basin for theirwater.

The Prime Minister John Howard has written tothe Independent Member for New England TonyWindsor giving an assurance that the Governmentis considering an ‘independent’ study into coalmining on the Liverpool Plains.

Map Source: BHP Billiton

05


5.3 Longwall Top Coal Caving

Longwall Top Coal Caving (LTCC) is a form oflongwall mining previously practised only in China.However, the method is currently being used on atrial basis in two longwall panels at the AustarColliery (formerly Southland Colliery) nearCessnock in the Newcastle Coalfield. SouthlandColliery was closed following a fire in 2003. It waspurchased a year later for $32m by the YanzhouCoal Mining Company of China, and renamedAustar Coal Mine. Yanzhou is among the fourlargest Chinese coal miners in eastern China, withsix underground mines in Shandong Provinceproducing more than 40Mtpa of coal, 90% ofwhich is extracted using LTCC.

The development of LTCC took place in Francemore than 20 years ago but has been furtherrefined in China for dealing with thick seams andwhere the Chinese government has decreed thatat least 85% of a seam must be extracted.

The front of a LTCC machine functions like astandard longwall system but with a secondarmoured face conveyer – an articulated chainconveyor that transports the coal along thelongwall face after it has been cut by the coalshearer – that runs behind the base of thesupports to clear coal that subsequently falls fromthe roof once the chocks have moved forward.

In 2000 the CSIRO signed an agreement to workwith the Chinese Yankuang Mining Group to studythe potential for LTCC in Australia. The CSIROconcluded that the method was suitable forseams of 4.5-12m thickness. This would not beapplicable in the Southern Coalfields of NSW butwould be in some of the seams in the Hunter,Newcastle and Gunnedah Basin coalfields.

According to the CSIRO, “Longwall top coalcaving offers significant reductions in cost andimproved capital utilization. The method couldpotentially double longwall recoverable tonnesmined per metre of gateroad development. Lessdevelopment metres, less frequent longwallmoves and the potential for a more even coal floware major advantages”. (CSIRO, Longwall Top CoalCaving, Fact Sheet, 2003)

The CSIRO also noted that “additional research isrequired particularly in the area of geotechnicalfeasibility”, and acknowledged that thegeotechnical elements of LTCC are not wellunderstood. Austar Mine’s Statement ofEnvironmental Effects predicts subsidencebetween 3.9 to 4.2 metres and maximum crackwidths of up to 90mm, although local residentsclaim to have been told that subsidence of up to6m may occur (Media Release by local residentJohn Harvey, 10/7/06).

06 REMEDIATION AND MONITORING


There is no long-term evidence that grouting,mortaring and a number of other remediationmeasures are capable of returning river systemsback to health following longwall mining.Environmental flows may not return without thecontinuing practice of replenishing flow with waterfrom the mine or purchased from town supplies orwater catchments. Changes in the chemicalcomposition of rivers and creeks from iron oxideleaching may not support the return of aquaticspecies to an area.

There is also the substantial problem that damagebetween the mine operations and the surface isoften undetectable. Some cracking occursbeneath alluvial, sandy deposits and simplycannot be seen. According to the EnvironmentalImpact Statement for BHPB’s Douglas Area 7Project, “It is … not possible to visually identifythe location and extent of additional fractures thatmay have occurred as a result of mining previouslongwalls”.

Sometimes proposed measures are not alwayspractical. Following the fish kills that occurred inthe Cataract River, BHP offered to restock theriver. This was unable to be done due to the lackof flow and water quality of the river, whichcontinues to the present day.

In 2004 the TEC commissioned Eco LogicalAustralia to produce a report into The Impacts ofLongwall Mining on the Upper Georges RiverCatchment. The report found that there werethree measures or considerations that must betaken in regard to the impacts of longwall mining.These were:

Avoidance

Amelioration

Rehabilitation.

This section draws largely on Eco LogicalAustralia’s report to assess these issues in a state-wide context.

6.1 Avoidance

Avoiding significant impacts is the key toecologically sustainable development and isfundamental for effective land use planning. In thecase of longwall mining identifying valuesvulnerable to impacts and being able to accuratelypredict where unacceptable impacts will occurforms the basis for sound strategic planning. Thisis best exemplified by not mining under or tooclose to rivers, creeks and underground aquifersthat are likely to be impacted.

The coal mining industry has a poor record onavoidance. The introduction of SMPs in 2004made some advances towards predictingsubsidence impacts. However unacceptable levelsof damage to water resources and natural featuresare still taking place across NSW. Miningcompanies’ SMPs are routinely approved withlittle or no additional conditions imposed by theDPI to avoid subsidence impacts and with a focuson amelioration and rehabilitation, along withongoing monitoring programs.

6.2 Amelioration

Where impacts are not avoided, ameliorating theintensity and longevity of the impacts is the nextobjective. Amelioration techniques include watertreatment, environmental flows, stress-relievingslots and grouting.

6.2.1 Water Treatment

Water from surface and underground operations inlongwall mines undergoes a number of treatmentsbefore being released back into the river systems.

06


These include settling ponds to facilitate removalof particles and chemical treatment to improvewater quality. DEC specifies minimum waterquality parameters for water being released intoriver systems. As well as the above treatments,mines use potable town water mixed with themine water to ensure that maximum salinity levelsare not exceeded.

6.2.2 Environmental Flows

To offset water loss and drops in water level as aresult of fracturing and extended periods of lowrainfall, numerous longwall coal mines releasesubstantial amounts water of into river systems asenvironmental flows. This assists in maintainingminimum water levels in ponds and channels andis intended as a temporary measure to be used inthe time between impact and when rehabilitationcan be implemented. Given Sydney’s water supplyproblems and environmental problems associatedwith low flow in dammed rivers, the release oflarge amounts of potable water to compensate forenvironmentally poor mine planning is consideredto be an unnecessary waste of a precious naturalresource.

6.2.3 Stress Relieving Slots

In an attempt to prevent fracturing of the rock barupstream from Marhnyes Hole, which wasfractured as a result of longwall mining in theUpper Georges River Catchment, a stressrelieving slot was drilled for a distance ofapproximately 28.5 metres. Whilst some fracturingstill occurred it was small in nature and on themargin of the slots’ effective area.

While this technique may prove effective, it wasinvasive and a number of factors prevent it frombeing carried out in all but the most extreme (andmost publicised) of cases. Due to the mechanicsinvolved it may not be possible to drill these typesof slots in steep environments or areas withoutvehicular access. For example, ameliorationequipment and materials being used in theWaratah Rivulet in the upper Woronora catchmentare being transported into the area by helicopter.

6.2.4 Grouting

Grouting is sometimes carried out as miningprogresses under an area. Difficulties faced bygrouting when used as an ameliorative measureinclude washouts and ongoing subsidence.Grouting as an effective measure to reduce theimpacts of longwall mining subsidence on riversystems is a contentious topic and is discussedfurther in Section 6.3.3.

6.3 Rehabilitation

The final option is to rehabilitate or remediatedegraded environments. Mining companies spendmillions of dollars each year on remediation works.Whilst some short-term results have beensuccessful, the long-term effectiveness ofrehabilitation techniques is currently unknown.The dominant forms of rehabilitation include:

Environmental flows, Mortaring, Grouting and theNatural sealing of rock fractures.

6.3.1 Environmental Flows

When used to maintain water flows over a longerperiod of time, environmental flows can besuggested to be a rehabilitation measure. Whilstthere are benefits to maintaining environmentalflows, they can lead to changes in waterchemistry and ecology and, given the need to mixwater with town water, may put pressure onpotable water supplies, particularly during droughtperiods. The long-term viability of maintainingenvironmental flows from potable water suppliesis low.

6.3.2 Mortaring

Site inspections of the mortaring that took placeas part of remediation work carried out atMarhnyes Hole identified cracking and flaking ofthe mortaring. This is believed to be a result offurther subsidence related movement and raisesdoubts about the effectiveness of this technique.

6.3.3 Grouting

The aim of grouting is to fill the fractures belowthe surface through which water has beenflowing. This reduces the redirection of waterfrom the surface and reduces the amount ofdissolved oxidants that are brought up when thewater resurfaces.

Negative impacts from grouting includedisturbance of vegetation and other surfacefeatures through access, drilling and the like, anddamage from source material extraction/supplyThere is also the serious problem of practicality –grouting cannot be applied to the thousands ofcracks, nor can all the works be effectivelymonitored.

The Minister for Primary Industry Ian Macdonaldand mining companies regularly claim thatgrouting has ‘repaired’ damaged rivers such as theCataract and the upper Georges.


6.3.4 Natural Sealing

Natural sealing on its own appears to be a slow ifnot ineffectual technique. Examples (based onrock staining and vegetation) show water levelsdropping in a number of river systems followinglongwall mining and possible natural sealing. Nosuch drops in water level were observed in areasthat had not been undermined suggesting cautionshould be exercised in relying on natural sealingas the sole rehabilitation technique.

6.4 Monitoring

As discussed in Section 4, monitoring is a keygovernment and industry response andbenchmark data is absent.

Since the damage occurred to the Cataract Riverand through the conditions enacted by the newapprovals process, extensive monitoring of waterquality and quantity takes place before and withevery longwall mining operation. Most monitoringprograms are conducted by mining companiesthemselves and sometimes by variousgovernment agencies, such as the SCA if miningis taking place within a supply catchment.

While programs that provide more information anddata about the effects of longwall mining on riversystems are no doubt beneficial in the long term,mining companies are using data taken frommonitoring programs to justify continued miningnear rivers. Highly generalised statements in mineplans, such as ‘flow observations indicate that theunderflow [the water that has disappeared downcracks] reappears as surface flow furtherdownstream’ (Helensburgh Coal, 2006) are maderoutinely without acknowledging the absence ofbaseline data as described by the CSIRO.

In the case of the Waratah Rivulet, the recentSMP referred to studies done in 2004 and 2005 tojustify more longwall panels, when the longwallpanel that had caused catastrophic damage to theriverbed was mined in 2006.

It is a routine practice of the miners and itsregulator to assume the most optimistic situationand to undervalue the extent of risk.

Cracking of the Waratah Rivulet bed, in Sydney catchment area

07 KEY ISSUES AND RECOMMENDATIONS


Despite the careless attitudes of industry and theMines department, government has receivedsufficient warning about the situation from a widerange of community groups and also keygovernment agencies. For instance the Water andSydney’s Future report (Hawkesbury-Nepean RiverManagement Forum, DPINR, 2004) to theMinister for Planning, Minister for NaturalResources and Minister for the Environmentfound that longwall mining in the Hawkesbury-Nepean catchment had the potential “to causeirreversible long-term damage to aquatic andgroundwater dependent ecosystems”.

The report made one recommendation regardingunderground coal mining in the catchment:

That all underground coal mining be required toeliminate existing impacts and to avoid futureimpacts upon the water supply system, rivers,streams and wetlands within the Hawkesbury-Nepean, Shoalhaven and Woronora catchments.(Hawkesbury-Nepean River Management Forum,2004, Recommendation PEF19)

The operation of coal mining under section 138 ofThe Mining Act 1992, and indeed under the newapprovals regime and SMP process, is theantithesis of the precautionary principle. Too manyrisks are being taken with natural resources,including a large volume of the Sydney catchment,and key items of infrastructure. Unlike damage toman-made structures, damage to naturalresources, ecosystems and places of recreationdo not attract financial compensation. This reflectsa lack of legal recognition for the damage beingcaused and the absence of an enforcementregime to protect environmental services andpristine environments that should be retained forthe benefit of future generations. Unlike man-made infrastructure, financial compensation for

damage to aquatic ecosystems is neither possiblenor advisable.

7.1 The Approvals Process

Although established to address environmentalimpact issues, Environmental Impact Statementsand Subsidence Management Plans submitted aspart of the new approvals process invariably statethat subsidence can be managed, yet offer noassured results from past monitoring andrehabilitation. New mines are approved with littleor no focus on avoidance, but instead onspeculative amelioration and rehabilitation andendless monitoring that simply records thedamage and does not inform the future.

The Department of Mineral Resources is a lawunto itself when it comes to final approvals fornew longwall mines. There are also significantquestions over the DMR fulfilling theirobligations to the public and the integrity oftheir desire to achieve good environmentaloutcomes.

In their annual report of 2003/04, the SCAreported that the Southern Coalfield RiverRemediation Committee, an interagencycommittee established to address the notinsignificant issue of rehabilitation ‘continued toencourage and oversee the remediation ofwatercourses that have suffered subsidencedamage as a result of underground coalmining’.

However the Committee has not met for overthree years and after making a number of inquiriesinto the Committee’s status, Rivers SOS wereinformed that it had been disbanded after theDMR moved to Newcastle.

The penultimate role in the new approvalsprocess, before the DMR makes a final

07


determination, is held by the SMP InteragencyReview Committee. The role of this Committee isto “advise on conditions for their approval and toparticipate in ongoing monitoring of subsidencemanagement”. Given the number of SMPs thatare approved by the DMR without modification,the ability of the Review Committee to influenceenvironmental outcomes for the better must bebrought into serious question.

An example of the problems faced by theInteragency Review Committee can be found inthe recent approval of the Appin 3 mine. Minutesof the Committee’s August 2006 meeting(obtained through FOI by Rivers SOS) noted that:

the SMP was deficient in the provision ofmanagement plans;

Illawarra Coal (BHPB) had been hard to obtaininformation from and when information wasreceived it was “minimal with no backupinformation”;

there was pressure to approve prior to thecompletion of management plans;

the SCA had commissioned an independentconsultant to determine a “suitable barrier” toprotect the Cataract River from cracking andthat a distance of 350m had been determined,and also that substantial discussion would needto take place on this before approval;

that it would be very difficult to grout andensure success and that the SCA was notconfident with the grouting managementprogram; and

that the SCA was going to produce a documentrecommending changes to approval conditions

Less than a month after the meeting Appin 3 wasapproved without any significant conditions andallowed mining to come to within 80m of theCataract River.

The rapid approval for Appin 3 following theproblems noted by the Interagency ReviewCommittee raises major concerns and proves thatrecommendations and concerns about protectingrivers, remediation and access to information frommining companies are ignored by the DMR whengranting new approvals.

Under the new approvals policy, SMPs arerequired to be publicly available and applicationsfor and determinations made on SMPs arerequired to be exhibited publicly on the DMR’swebsite. However, the list exhibited is incompletewith the SMPs for several major longwall minesnot included. The DMR has also failed to respondto the TEC’s request for information on thisproblem.

The intention of government policy should be topreserve the ecological integrity of water supplycatchments, including maintenance of waterquality and flow as paramount to the production ofcoal. This requires a much improved protectionand an independent regulatory system for miningin these areas. It is necessary to prohibit highimpact coal mining in drinking water catchmentsand other environmentally sensitive areas.

Recommendations: The Department ofMineral Resources (DMR) has a conflictof interest in regulating mining, as theyare a strong promoter and advocate ofmining. The DMR should be immediatelyremoved as the approval body forlongwall mines.

An independent regulator with the powerto prevent longwall mining in sensitivesites is required, in addition to muchgreater involvement of Planning NSW,the Department of Environment andConservation (DEC) and the SydneyCatchment Authority (SCA).

Additionally provide monthly publicinternet reporting of mine subsidencedamage monitoring and advice from anindependent expert ecologicalcommittee.


7.2 Buffer Zone

Fifteen rivers in New South Wales have beendamaged since the 1990’s as a result of longwallmining with a further seven under threat fromcurrent plans (Rivers SOS 2006).

As noted at the beginning of this section, in 2004DIPNR’s Hawkesbury-Nepean River ManagementForum made a recommendation to “eliminate” allexisting impacts by longwall mining on Sydney’swater supply catchment.

In an assessment of coal mining potential in theUpper Hunter Valley, the NSW Department ofPlanning (NSW Department of Planning, 2005)made the recommendation ‘That formal policy toavoid or minimise the potential impacts of coalmining on major streams or aquifers andguidelines for assessment under Part 3A EP&AAct of such potential impacts by major coal minesbe developed by DoP in consultation with DNRand DPI’. In his media release following theassessment, Planning Minister Frank Sartor notedthat the recommendations included protecting thePages River, ‘from any significant impact from coalmining’ (NSW Minister for Planning, 20/12/2005).

In their key threatening process declaration, theNSW Scientific Committee (NSW ScientificCommittee, Alteration of habitat followingsubsidence due to longwall mining - keythreatening process declaration, 2005) notes that:

The surface area affected by ground movement isgreater than the area worked in the seam (Bell etal. 2000). In the NSW Southern Coalfield,horizontal displacements can extend for more thanone kilometre from mine workings (and inextreme cases in excess of three km) (ACARP2002, 2003)

In their report, Mine Subsidence in the SouthernCoalfield, Holla and Barclay state that “horizontalmovements of up to 25 mm near Cataract Dameven when underground mining was about 1500mfrom survey stations.”

Protection and buffer zones are already enforcedin regard to protecting man-made infrastructurefrom the impacts of longwall mining. Dam walls,railway lines and bridges all have set conditions toprevent longwall panels from coming too close.The necessity of protecting railway lines stemsfrom the 1970s when underground coal miningcaused significant damage to the Stanwell ParkRailway Viaduct and the creek beneath. Sectionsof the viaduct had to be replaced, and trains arestill obliged to slow down at this point. Thiscracking was caused by mines that wereapproximately 130m from the viaduct.

This concept can easily be extended toincorporate key natural areas such as supplycatchments, river systems, alluvial aquifers cliffsand other important landmarks.

TEC believes that special legislation should bepassed to ensure protection, along with strongpenalty provisions – the Appendix contains legaldrafting instructions to achieve this.

Recommendations: To enact in the firstparliamentary session after the 2007State Election, legislation for a 1kmprotection zone around rivers andstreams underlain by proposed longwallmining; development of additionalprotection measures from other miningimpacts and compliance measures.

A 1km mining exclusion zone aroundrivers and groundwater aquifersimmediately be made mandatory in allmining licences for all current longwallsthat have not proceeded to secondworkings.


7.3 Southern Coalfields Inquiry

On December 6th 2006 NSW Planning MinisterFrank Sartor announced an Independent Inquiryinto the NSW Southern Coalfields. The Terms ofReference are:

1. Undertake a strategic review of the impacts ofunderground mining in the Southern Coalfieldon significant natural features (i.e. rivers andsignificant streams, swamps and cliff lines),with particular emphasis on risks to waterflows, water quality and aquatic ecosystems;and

2. Provide advice on best practice in regard to:

a) assessment of subsidence impacts;

b) avoiding and/or minimising adverse impactson significant natural features; and

c) management, monitoring and remediation ofsubsidence and subsidence-related impacts;and

3. Report on the social and economic significanceto the region and the State of the coalresources in the Southern Coalfield.

The Inquiry comes in the wake of damage tonumerous rivers and creeks in the region and is adelaying tactic that will allow more damagingmining. New longwall mines may still be plannedand approved in the Southern coalfields while theInquiry proceeds. The Minister has announcedthat he will impose a new approval process after

2010, by which time many more longwalls willhave been granted consent under the currentfailed regime, extending operations beyond 2010.

Damage caused by longwall mining is a statewideproblem and the Inquiry should expand its scopebeyond the Southern Coalfield.

Recommendations: The NSWGovernment should institute a newprotection regime in 2007.

A moratorium on new longwall minesshould be established until the Inquiryhas handed down its findings.

It should also investigate longwallmining in supply catchments and theSpecial Areas as a separate term ofreference.

Finally, the scope of the Inquiry shouldbe expanded to acknowledge theprimacy of the precautionary principleand address the damage done to riversystems and water resources acrossNSW by coal mining.

08 APPENDIX – EDO ADVICE


Our Ref: 2006150

28 November 2006

Dave Burgess

Total Environment Centre

Level 4, 78 Liverpool Street

Sydney NSW

Dear Dave,

Longwall Mining

The Environmental Defender’s Office (EDO) has been instructed by the Total Environment Centre (TEC) toprepare drafting instructions for legislation in relation to longwall mining. In particular, the instruction relateto establishing:

a total prohibition on mining within 1km of waterways (including rivers and wetlands) in NSW,

appropriate penalties for breach of this buffer zone, and

making Subsidence Management Plans (SMPs) more robust.

To achieve these ends, any legislation would need to contain adequate provisions relating to:

environmental protection object clause

prohibition of mining

offence provisions

open standing

any exemptions clearly delineated

concurrence of the Department of Environment and Conservation

public participation

These are two options that are available to achieve the desired outcome:

1) A new, stand alone piece of legislation, or

2) Amending existing legislation.

These will be considered separately below. Within each option two alternatives will be considered: anabsolute prohibition of mining within the buffer zone, and a conditional prohibition subject to consent.

08


1. Stand alone legislation

Title

Example: Protection of Waterways (Longwall Mining) Act 2007.

Objects clause

A new separate Act would require appropriate objectives. The overriding objective is to prohibit longwallmining within 1km of waterways to ensure protection of water ways and avoidance of subsidence. Theobjects clause should also state that the Act is to operate in accordance with the principles of ecologicallysustainable development. Since it is well shown that longwall mining does cause subsidence withsignificant environmental impacts on river structure and rehabilitation techniques are doubtful in theireffectiveness, such an objective would be consistent with the precautionary principle.

Prohibition

A clear provision is required stating that mining is prohibited within 1km of waterways.

“Mining” activities and “waterway” should be clearly defined.

Exemptions

Provisions should be drafted to clarify how the legislation applies to existing mining approvals andactivities currently within the 1km buffer zone.

Offence provisions

The new Act would have to establish an appropriate enforcement mechanism for breaches of the Act,such as carrying out a prohibited activity in the buffer zone (without an existing licence); breach of arelevant condition; or providing false and misleading information. The accepted view is that stipulated inthe High Court case of He Kaw Teh. It recommends a 3-tiered structure for offences.

Tier 1 offences are the most serious offences and involve willful or negligent activities that breach thebuffer zone. That is, an appropriate state of mind must be proven in addition to the breach. Suchbreaches may lead to imprisonment in addition to a monetary penalty.

Tier 2 offences are ‘strict liability offences’. This means that to prove the offence, the prosecutor doesnot need to show that the defendant intended to breach the buffer zone or was negligent. Theprosecutor only has to prove that the defendant conducted mining activities within the prohibited zone,or conducted such activities without a licence. The appropriate penalty is a monetary fine.

A Tier 3 offence is the least serious of the three categories of offences. A Tier 3 offence is a Tier 2offence for which a penalty notice can be issued. These may be appropriate for breaches of ancillaryprovisions of the Act.

Open standing

The new Act should include provision for the public to enforce breaches of the Act under open standingprovisions. The standing clause should provide that any person may bring proceedings to challenge aMinister’s decision to award or refuse a permit (merits appeals), or to take civil proceedings to enforcebreaches of the Act or legal errors by the Minister in granting consents (judicial review).

2. Amendment to existing legislation

We refer to our previous advice (June 2004) regarding the current institutional, planning and regulatoryframework for mining which included reference to the following Acts:

Coal Acquisition Act 1981

Coal Acquisition Act 1981

Coal and Oil Shale Mine Workers (Superannuation) Act 1941

Coal Industry (Industrial Matters) Act 1941

Coal Industry Act 2001


Coal Mines (Health and Safety) Act 2002

Coal Mines Regulation Act 1982

Coal Mining Act 1973

Coal Ownership (Restitution) Act 1990

Environment Protection and Biodiversity Conservation Act 1999 (C’th)

Environmental Planning and Assessment act 1979

Environmental Planning and Assessment Regulation 2000

Fisheries Management act 1994

Mine Subsidence Compensation Act 1961

Mines Inspection (Amendment) Act 1998

Mines Inspection Act 1909

Mining Act 1909

Mining act 1973

Mining Act 1992

Mining Legislation (Health and Safety) Act 2002

Mining Regulation 2003

Mining Statute 1865

National Parks and Wildlife Act 1974

Protection of the Environment Operations Act 1997

Sydney Water Catchment Management Act 1998

Rivers and Foreshores Improvement Act 1948

Threatened Species Conservation Act 1995

Water Act 1912

Water Management Act 2000

As is apparent, there are many Acts that are potentially relevant to regulating longwall mining. Ifamendment of existing legislation is preferred to the option of stand alone legislation as discussed above,it would be necessary to ensure consistency between all existing instruments. This could be done byincluding key amendments on one Act, for example, the Mining Act 1992 or Rivers and ForeshoresImprovement Act 1948, and ensuring that the amendments cannot be overridden by loopholes in existinglegislation.

Objects clauses

Existing legislation may need to be amended to insert an appropriate waterways protection objectiveincluding reference to a prohibition on certain activities within 1km of waterways.

Prohibition

Existing legislation would need to be amended to include provisions stating that mining is prohibitedwithin 1km of waterways.

If the key offence prohibition is contained in one Act, for example in the Mining Act 1992, it is importantto also state that other legislation cannot override the prohibition.


Exemptions

Any new Act would require provisions exempting certain activities from the prohibition of mining such asexisting uses.

Existing provisions that may allow exemptions to the prohibition should be omitted by the amendinglegislation. (It is important to note that the removal of certain rights may give rise to compensation).

Offence provisions

A similar enforcement regimen would be required as for a stand alone Act, as discussed above.

Open standing

As noted above, amendments should state ‘any person’ may bring proceedings to enforce a breach of theprohibition or challenge a decision. It is important to note that the Mining Act 1992 and RFI Act 1948 donot provide such standing currently.

Example: Potential amendments to the Rivers and Foreshores Improvement Act 1948, and the Mining Act1992

The RFI Act 1948 currently applies to ‘protected waters’. These are defined as a river, lake into or fromwhich a river flows, coastal lake or lagoon (including any permanent or temporary channel between acoastal lake or lagoon and the sea).

The Act regulates certain activities within ‘protected land’. Such land is defined as:

(a) land that is the bank, shore or bed of protected waters, or

(b) land that is not more than 40 metres from the top of the bank or shore of protected waters(measured horizontally from the top of the bank or shore), or

(c) material at any time deposited, naturally or otherwise and whether or not in layers, on or under landreferred to in paragraph (a) or (b).

Section 22B of the RFI Act 1948 currently prohibits excavation on or under protected land unless a permithas been issued by the Minister of Public Works. Further, a person must not do anything which obstructsor detrimentally affects the flow of protected waters without a similar permit. Prima facie, this sectionwould mean that longwall mining activities cannot proceed unless a relevant permit has been given.However, this is not the case due to section 22H. It states that the above section does not apply to anylease, licence or permit relating to mining. Hence, as long as a relevant mining lease has been issued, theRFI Act 1948 does not apply. In order to achieve a 1km buffer around and under rivers, this exclusionwould have to be removed. Furthermore, the definition of ‘protected land’ would have to be amended toincrease the protected area from 40m to 1km for the purposes of longwall mining. It may also beappropriate to make the Department of Environment and Conservation a concurring authority.

The Mining Act 1992 will also need to be amended to ensure that no mining lease is issued where theproposed mining is to take place within 1km of protected waters, or no lease is approved withoutobtaining a relevant permit under the RFI Act. Part 5, Division 2 of the Act contains restrictions on thegrant on mining leases so that would be the appropriate section of the Act to include such a restriction.


3. Subsidence Management Plans

Legislative amendments may have implications for Subsidence Management Plans and Departmentalpolicies and guidelines.

If the aim of the new/amended legislation is to prohibit mining within a 1km buffer, but to allow suchmining to proceed with a relevant consent, licence or permit; then appropriate criteria will need to bedrafted which the consent authority must consider before granting or refusing an application. The existingSubsidence Management Plan (SMP) regime may form a logical part of that process, either as one of thecriterion to be considered or as a condition of consent. To be robust and effective, SMPs shouldencapsulate five elements:

1) community participation

2) legislative force

3) appropriate criteria for the making of SMPs

4) processes to challenge the granting or refusal of consent to a SMP.

5) effective monitoring of the plan.

Community Participation

The community already has a right to participate in the SMP process. All applicants must advertise theirintention to develop a draft SMP in a local and a State-wide newspaper; identify and consult with alldirectly affected landholders and local councils and take their views into account. Applicants mustreadvertise when the draft SMP is finalised and submitted to the Department of Primary Industries. Theadvertisements must contain details of where the SMP can be accessed by the public. All members ofthe community are free to make submissions on the draft SMP which must be considered by theDepartment of Primary Industries.

Legislative force

Under the existing system, SMPs must be prepared as part of the application process. The requirementto prepare SMPs is attached as a condition of mining leases. The plans assist in assessing the subsidencepotential of new underground mines and extensions to existing mines. However, since SMPs are requiredas conditions of mining leases, they do not have the same statutory protection as express provisions inan Act would. SMPs could therefore be strengthened through amendments to the Mining Act 1992making SMPs compulsory for all applications. Currently, there is nothing preventing the lease conditionsfrom being altered for particular mining applications. There would be no statutory recourse in such anevent. An appropriate provision in the Act would be one stating that SMPs are compulsory for all miningactivities that are likely to cause subsidence, and a requirement for SMPs to be approved before theconsent to mine is given.

Appropriate criteria for making of plans

Criteria already exist for the making of SMPs. These are founds in the Department’s Guideline forApplications for Subsidence Management Approvals. Criteria include an assessment of the economic andsocial benefits of the mine, proposals for rehabilitation of subsidence impacts and proposals for groundand surface water management. As part of their application, applicants must also report on the views ofthe public and how these views will be taken into account. However, the practice has been to allowlongwall mining and subsidence with a commitment to monitoring and rehabilitation, if possible. Theprimary criteria on proceeding to a SMP should be whether there can be an absolute assurance thatwaterways will not be damaged.


Processes to challenge the granting or refusal of consent to a SMP.

There are currently no processes that allow the public to enforce a breach of a SMP, nor challenge thegranting of one. Merits review and judicial review should be available.

Effective monitoring of the plan

There is currently a Subsidence Management Plan Review Committee established under the Departmentof Primary Industries. Its task includes an annual review of SMPs and assessing the results of monitoringdata supplied by the mining companies.

Commentary

The NSW Government seems to lend support to a buffer zone around waterways. In December 2005, theDepartment of Planning released Coal Mining Potential in the Upper Hunter Valley - StrategicAssessment. In reviewing the potential subsidence effects of coal mining in the Hunter Region, the reportstates that such effects “can be avoided by adopting a policy to restrict where appropriate coal minedevelopment within or beneath the alluvium or alluvial aquifers of major streams and rivers throughout theHunter Valley”. Furthermore, the (then) Department of Infrastructure, Planning and Natural Resources,released a set of stream/aquifer guidelines in April 2005. These guidelines propose that barriers should bemaintained (up to 150 metres) between mining operations and water sources. However, the Departmentof Natural Resources has stated that these guidelines only apply to the Hunter Region and do not formpart of government policy. Nevertheless, it is acknowledgment by government of the need to protectwaterways from subsidence effects caused by longwall mining.

For further information, please contact [email protected] or 9262 6989.

Yours sincerely

Environmental Defender’s Office Ltd

Rachel Walmsley

Policy Director

09 REFERENCES


BHP Billiton, Environmental Impact Statement andSubsidence Management Plan, Douglas Area 7Project, 2006

BHP Billiton, Illawarra Coal Holdings Pty Ltd,Longwall Mining and Subsidence Management,Letter from Colin Bloomfield to various politiciansand local councils, 2006

Colong Foundation for Wilderness, Briefing –Mining Impacts and the Metropolitan Catchments,2001

CSIRO, Audit of the Sydney Drinking WaterSupply Catchments managed by SydneyCatchment Authority, Final Report, November2002

CSIRO, Longwall Top Coal Caving, Fact Sheet,2003

Eco Logical Australia, The Impacts of LongwallMining on the Upper Georges River Catchment:Report to Total Environment Centre, 2004

Environment Liaison Office, Protecting the NSWEnvironment, 2006

Hawkesbury-Nepean River Management Forum,Water and Sydney’s Future: Balancing the valuesof our rivers and the economy, Department ofInfrastructure, Planning and Natural Resources,2004

Healthy Rivers Commission, Independent Inquiryinto the Woronora River System, Draft Report,1999

Helensburgh Coal, Metropolitan Colliery Longwall14-17 Subsidence Management Plan Application,May 2006.

Holla and Barclay, Mine Subsidence in theSouthern Coalfield, NSW, Australia, Department ofMineral Resources, 2000

Mudgee Environment Group, website,www.savethedrip.com

NSW Minister for Planning, Upper Hunter OffersLimited Coal Mining Potential, Media release,20/12/05

National Parks Association, National Parks Journal,Vol 45, No 4, 2001

National Parks Association Macarthur Branch,Submission Appin Area 3, November 2005

NSW Department of Land and WaterConservation, Submission to Dendrobium CoI,2001

NSW Department of Mineral Resources, NewApproval Process for Management of Coal MiningSubsidence, 2003

NSW Department Of Planning, Proposal by WhiteMining Ltd to Develop the Ashton Coal Project atCamberwell, 2002

NSW Department of Planning, Coal MiningPotential in the Upper Hunter Valley: StrategicAssessment, 2005

NSW Department of Planning, Major ProjectAssessment: Angus Place Coal Project, 2006

NSW Department of Primary Industries, AnnualReport, 2004/05

NSW Department of Primary Industries, NewSouth Wales Coal Industry Profile, 2005

NSW Greens, NSW Coal Affected Communitiesreport, 2005

NSW Minerals Council, Coal Taxation in NSW,Implications for a Sustainable Industry: Killing theGoose that Laid the Golden Egg, speech by DrNikki Williams to the Australian coal Conference,2004

09


NSW Minerals Council, Preliminary Listing –Longwall Mining Key threatening Process, 2005

NSW Minerals Council, Community Engagementin the NSW Minerals Industry, NSWMC website

NSW Scientific Committee, Alteration of habitatfollowing subsidence due to longwall mining - keythreatening process declaration, 2005

NSW Scientific Committee, Newnes PlateauShrub Swamp in the Sydney Basin Bioregion -endangered ecological community listing – finaldetermination, NSW Scientific Committee, 2005

Syddell, Longwall of China to debut Down Under,Reed Business Information website, July 2005

Reynolds, Justice R.G., Report of theCommissioner on an Inquiry into Coal Miningunder or in the vicinity of the Stored Waters of theNepean, Avon, Cordeaux, Cataract and WoronoraReservoirs, 1977

Rivers SOS, Addressing BHP Billiton’s SubsidenceManagement Plan for Appin 3, 2005

Rivers SOS, NSW Rivers of Shame, 2006

Rivers SOS, Submission Concerning Special AreasStrategic Plan of Management to SCA, 2006

Sivakumar, Singh and Morton, Mine WaterManagement and Controls in an EnvironmentallySensitive Region, Mine Water and TheEnvironment, Vol 13, No 1, 1994

SMP Interagency Review Committee, Minutes ofMeeting, 2nd August 2006

Sydney Catchment Authority, Annual Report,2003/04

Total Environment Centre and the ColongFoundation for Wilderness, Joint PrimarySubmission to the Commission of Inquiryregarding the Proposed Dendrobium Coal MineProject, 2001

University of Wollongong, Mining and Engineering,Longwall Mining website,www.uow.edu.au/eng/longwall

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