evaluation of the bickham coal mine water management planbcag.com.au/submissions/frogtech for water...

1The conclusions and recommendations expressed in this material represent the opinions of the authors based on the data available to them. The opinions

and recommendations provided from this information are in response to a request from the client and no liability is accepted for commercial decisions or

actions resulting from them. Please cite this work appropriately if portions of it are copied or altered for use in other documents. The correct citation is

Hostetler S, et al, 2009, Evaluation of the Bickham Coal Mine Water Management Plan, Confidential Report by FrOG Tech Pty Ltd.

Evaluation of the Bickham Coal Mine Water Management Plan

FrOG Tech Pty Ltd T: +61 (0)2 6283 4800

PO Box 250 - Level 1, 2 King Street F: +61 (0)2 6283 4801

DEAKIN WEST, ACT 2600 W: www.frogtech.com.au

CANBERRA, AUSTRALIA E: [email protected]

ABN: 29 129 411 981

S Hostetler, BSc ................ [email protected]

Table of Contents

Tom Loutit, PhD

Jane Blevin, PhD

Karen Romine, PhD

Lynn Pryer, PhD

Karen Connors, PhD

Cedric Jorand, PhD

Andrew Krassay, PhD

Rob Hus, PhD

Donna Cathro, PhD

Nick Direen, PhD

Lisa Hall, PhD

Silvano Sommacal, PhD

Zhiqun Shi, PhD

Marie-Aude Boddonet, PhD

Yvette Poudjom Djomani, PhD

Stephen Hostetler, BSc (Hons)

Marina den Hartog, MSc

Rosalyn Canicula, MSc

Nicola Fry, MEStud

Martin Sykes, MEarthSc

Janssen Canicula, BSc

Julie Sandow, BEIS

James Chapman, MA

John Vizy, DipGS

Philip Henley

Allan Mills, BE

Adrian Dehelean, ADipSI

Cath McKenna

Meredith Guy-Villon, DipFA

Matthew Valetich

Stephen Hostetler Tom Loutit

Lead Interpreter Managing Director

FrOG Tech Project Team:

Evaluation of the Bickham Coal

Water Management PlanNovember 2009

FrOG Tech Project Code:

HUN801

Author:

www.frogtech.com.au

Executive Summary ........................................................................ 2

Analysis of Known Risks ................................................................... 3

Additional Risks ................................................................................ 4

Introduction ..................................................................................... 5 Hunter Region Climate ..................................................................... 7 Blandford Region Geology ................................................................ 8 Regional Groundwater Contours .................................................... 10

Locations of Stream Gauges and Analysis of Data Used ......... 11 Hunter Region Gauge Locations .......................................... 12 Pages River at Blandford Gauge Location ........................... 13 Pages River at Blandford Data Used for Analysis ................ 14 Pages River at Gundy Gauge Location ................................ 15 Pages River at Gundy Data Used for Analysis ..................... 16 Kingdon Ponds Creek at Parkville Gauge Location ............. 17 Kingdon Ponds Creek at Parkville Data Used for Analysis .. 18

A Full Analysis of Potential Impacts ........................................... 19

Catchment At Risk ........................................................................ 20 Pages River at Blandford ..................................................... 21 Pages River at Gundy .......................................................... 22 Kingdon Ponds Creek at Parkville ........................................ 23

Increase In No Flow Days ............................................................ 24 Pages River at Blandford ..................................................... 25 Pages River at Gundy .......................................................... 27 Kingdon Ponds Creek at Parkville ........................................ 29

Effects Of Climate Change ........................................................... 31 Pages River at Blandford ..................................................... 32 Pages River at Gundy .......................................................... 34 Kingdon Ponds Creek at Parkville ........................................ 36

Supplemental Flow Inadequate ................................................... 38 Pages River at Blandford ..................................................... 39 Pages River at Gundy .......................................................... 40

Kingdon Ponds Creek at Parkville ........................................ 40

Conclusions .................................................................................. 42

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mailto:[email protected]











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Executive Summary

This document provides an assessment of the risks to the water supply identified

by the proponents of the Bickham Mine as set forth in “Bickham Coal Project

Water Resource Assessment and Draft Water Management Plan”: (WMP).

While a number of risks were identified, the one with the greatest potential for

affecting the flow of Pages River and Kingdon Ponds Creek was identified as the

effect of reduced baseflow on the river system.

This study shows the both Pages River and Kingdon Ponds Creek are already

highly stressed due to the combination of landuse changes, presence of farm

dams, climate change and current extractive users (see pages 20-23).

Groundwater modelling predicts that the maximum effect (Year 35) on baseflow

will be 220 KL/day for Pages River and 15 KL/day for Kingdon Ponds Creek.

Had the mine existed throughout the monitoring history of the river system (see

pages 24-30), the additional decrease in baseflow due to the mine would have

increased (compared to current conditions) the number of historic no flow days

(days when the river ceased to flow) from:

• 30 to 96 days for Pages River at Blandford (in addition to baseflow impacts,

there will also be 0.3% decrease in catchment due to the mine which will have the

effect of decreasing runoff by an average of 108 ML/yr);

• 123 to 477 days for Pages River at Gundy; and

• 1072 to 1208 days for Kingdon Ponds Creek at Parkville.

In especially dry years (eg. 2006-2007) the effects are more apparent. For

example had the mine existed in 2006, the number of no flow days of the Pages

River at Gundy would have increased from 9 to 98.

In addition to the increase in no flow days, the presence of the mine will decrease

the 10%ile (1 in 10 year event) flows by 12% for Pages River at Blandford, 22%

for Pages River at Gundy and 8% for Kingdon Ponds Creek at Parkville.

If the combined effects of climate change and reduced baseflow (see pages 31-

37) are included in the analysis (10% decrease in runoff) then the number of

historic no flow days (compared to current conditions) would increase from:

• 30 to 693 days for Pages River at Blandford;

• 123 to 1694 days for Pages River at Gundy; and

• 1072 to 1844 days for Kingdon Ponds Creek at Parkville.

The combined mine/climate change scenario will also strongly affect flow statistics

with the median (50%ile) flow being reduced by 10% for Pages River at

Blandford, 6% for Pages River at Gundy and 10% for Kingdon Ponds Creek at

Parkville.

Executive Summary

The proponents of the mine plan to supplement the water supply in the river/creek

this is scheduled to cease 2 years after mining finishes. However, modelling (see

pages 38-41) shows that the reduced baseflow will continue to affect the number

of no flow days until about Year 93 (68 years after mining ceases) for Pages

River; and that pre-mine baseflow inflows will never recover (at least within the life

of the groundwater model) for Kingdon Ponds Creek.

Existing factors such as landuse change, farm dams, other extractive users and

climate change means that the ecology of Pages River and Kingdon Ponds Creek

are already stressed. The additional impact caused by the impost of the Bickham

Mine could provide a „tipping point‟ beyond which the ecology of the river will not

easily return.

It should be noted that any future expansion of the mine will likely alter the

assumptions of the current groundwater model and will result in a further

reduction in baseflow in both Pages River and Kingdon Ponds Creek.












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Analysis Of Known Risks

Assessment of the risks identified in the Bickham Coal Project Water Resource Assessmentand Draft Water Management Plan (WMP).

Risks coloured green are though to be of low risk, those coloured yellow of moderate riskand those coloured red of high risk.

• Direct leakage of Pages River to the pitGroundwater modelling shows that water from Pages River will not enter the pit.

• Excessive inflow rate to pitDue to the low hydraulic conductivity of the aquifers in the mine area shows thatinflows to the mine will be manageable. However, the total volume of water inflowinto the pit is still large at 26.5 GL (1060 ML/yr). This is ~15% of recharge.

• Excessive baseflow impacts to either the Pages River or Kingdon Ponds CreekAny water extraction will have some effect on other users. Groundwater modellingshows that maximum baseflow impact (Year 35) will be 220 KL/day for Pages River and15 KL/day for Kingdon Ponds Creek. Detailed analysis of the historic flow record (seefull analysis on Pages 19-41) shows that due to baseflow decrease caused by the minethe number of historic no flow days (days when the river/creek ceases to flow) wouldhave increased from 30 to 96 for Pages River at Blandford, from 123 to 477 for PagesRiver at Gundy and from 1072 to 1208 days for Kingdon Ponds Creek at Parkville.

The reduced baseflow caused by the presence of the mine will continue to affect thenumber of no flow days until about Year 93 (68 years after mining ceases) for PagesRiver; while pre-mine baseflow levels will never recover (at least within the life of thegroundwater model) for Kingdon Ponds Creek.

In addition to the increase in the number of no flow days for Pages River and KingdonPonds Creek, the presence of the mine will alter the river’s flow characteristics up tothe median flow statistics.

Existing factors such as landuse, farm dams, other users and climate change meansthat the ecology of Pages River and Kingdon Ponds Creek are already stressed. Theadditional impact caused by the impost of the Bickham Mine could provide a ‘tippingpoint’ beyond which the ecology of the river can not easily return.

• Very low groundwater inflows to pitGroundwater modelling shows that groundwater inflows to the pit should take care ofthe mine’s water needs.

Analysis of Known Risks

• Interception of saline groundwater that might significantly elevate the salinity orlower the pH of the groundwater discharge into the pit or the dewatering boresThe proponents did fairly thorough sampling of groundwater from multiple aquifers inthe mine region. The average salinities of all units are relatively low, however in someof the coal seams salinities can be over 3000 mg/L. While still low (stock quality) caremust be taken with use of the higher salinity water (shandying etc.) to prevent anyproblems.

• Salinity of in-pit water post-mining and whether this could adversely impactgroundwater quality around the pitDue to the combination of capture of runoff and the high quality of groundwaterinflows, the in-pit water id modelled to be less than Pages River.

• Salinity of stormwater infiltrating through the out-of-pit dump and whether thiscould adversely impact on groundwater/surface water qualityI think that this risk is low.

• pH changes from any potential acid mine drainage and whether this could adverselyimpact on groundwater/surface water qualityAcid mine drainage is a major problem in many coal mines. Bore OH86 from the ASeam has a minimum lab pH of 3.31(~equivalent to about the pH of orange juice). Theproponents should provide more specific information on how they will dispose ofhighly acidic water.

• Drawdown interferencewith existing water supply bores, wells or soaksThe proponents of the mine have promised to come to a remediation agreement withany affected users. However, as any potential effects can last up to 70 years beyondthe life of the mine, the proponent should put into place a plan to address legacyissues.












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Additional Risks

In addition to the risks identified in the WMP, FrOG Tech has identified the followingadditional risks.

Risks coloured green are though to be of low risk, those coloured yellow of moderaterisk and those coloured red of high risk.

• The groundwater model is a fairly simplistic both structurally and stratigraphicallyThe groundwater model prepared by Aquaterra calibrates well with current conditions.However, it may fail to predict the full effects of mining. This is because the UpperHunter Region lies at the junction of the Sydney Basin, Gunnedah Basin and the NewEngland Fold Belt and contains multiple large-scale faults and complex stratigraphy. Evenwithin formations there can be high permeability zones depending on the facies setting.Such high permeability zones are difficult to resolve through drilling alone. A full studyutilising the full range of geoscientific tools such as geophysics, seismic and basinmodelling will ensure that the groundwater model is fully representative of the area.

•Reactivation of faults and fractures due to removal of rocks due to mining.Relaxation of dominant stress direction due to the removal of large volumes of rock cancause currently closed fractures to re-open. While the hydraulic conductivity of fracturesin the Upper Hunter are currently low, changes in stress conditions can increasehydraulic conductivities by 3-4 orders of magnitude.

• Effects of increased recharge due to irrigation of the excess mine water not includedin the groundwater modelIrrigation inevitably causes an increase in recharge below the irrigated crop. The mineproposes to use excess pit inflow water to irrigate pasture on its land at ‘South Bickham’and “Glencoe’ properties. The longterm effects of changing recharge conditions in theseareas are not known.

Additional Risks












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INTRODUCTION

TO AREA

Introduction












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Blandford Region: Satellite Image

Blandford Region

Figure 1:Image Source: Google Maps












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Hunter Region Climate: Comparison of recent to longterm

Recent rainfall (1998-2007) in theHunter region has been generally at orabove the longterm average (1900-2007). Data is from ftp://ftp-anon.dwd.de/pub/data/gpcc/PDF/GPCC_intro_products_2008.pdf.

Despite the slightly above averagerainfall there has been an over alldecrease in streamflow in the keygauges in the Upper Hunter (see Pages11-18).

In addition, climate change is forecastto decrease rainfall by ~3% whichequates to a decrease of runoff of~10% (Appendix 19 page 34).

Hunter Region Climate

Figure 2:



ftp://ftp-anon.dwd.de/pub/data/gpcc/PDF/GPCC_intro_products_2008.pdf






















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Blandford Region: Geology (Formations)

Stratigraphy of the Sydney Basin

The Sydney Basin contains up to 5500m of mostlyPermian to Triassic age sediments that thin to thewest across a basement-controlled depositionalhinge, and around the margins of the basin as aresult of uplift. Cenozoic sediments occur inisolated parts of the onshore basin and as aprogradational wedge up to 700+m thick in theoffshore basin.

The detailed stratigraphic nomenclature of theSydney Basin can be quite complex due to thenumber of locally mapped formations, membersand beds – most being lithologically definedBlevin, J., Hall, L., Chapman, J., and Pryer, L., 2007.Sydney Basin Reservoir Study. Report for the NSWDepartment of Primary Industrieshttp://www.dpi.nsw.gov.au/__data/assets/pdf_file/0006/191814/Sydney_Basin_Reservoir_Study.pdf).

Blandford Region: Geology

Figure 3:



http://www.dpi.nsw.gov.au/__data/assets/pdf_file/0006/191814/Sydney_Basin_Reservoir_Study.pdf




























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Blandford Region: Structural Elements

The proposed mine at South Bickham is locatednear the junction of the Gunnedah Basin, SydneyBasin and the New England Fold Belt.

The proposed mine is also located near theHunter-Mooki Thrust Fault. (Blevin, J., Hall, L.,Chapman, J., and Pryer, L., 2007. Sydney BasinReservoir Study. Report for the NSW Departmentof Primary Industrieshttp://www.dpi.nsw.gov.au/__data/assets/pdf_file/0006/191814/Sydney_Basin_Reservoir_Study.pdf).

Blandford Region

Figure 4:






























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Hunter Region DEM: Regional Groundwater Contours

Using standing water levels (SWL) values derivedfrom the NSW Borehole database, FrOG Techproduced a set of regional groundwater levelcontours for the unconfined aquifer.

As expected, the groundwater level contoursgenerally follow the landscape. The regioncontains a major groundwater divide with thenorthwestern corner of the map flowing towardsthe alluvial aquifers of the Namoi River. Themajority of the region however flows into theSydney Basin.

NB: Groundwater information is from the Pineenadatabase INSW bore database). Water levels wereconverted from the depth to water table and boreheight from the 9-second DEM.

Regional Groundwater Contours

Figure 5:












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LOCATIONS OF STREAM

GAUGES AND ANALYSIS OF

DATA USED

Locations of Stream Gauges and Analysis of Data Used












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Hunter Region DEM: Drainage and Gauge Locations

There are three key gauges located in thevicinity of the mine.

The gauges are:

• Pages River at Blandford (210061)• Pages River at Gundy (210052)• Kingdon Ponds Creek near Parkville

(210093)

Hunter Region DEM

Figure 6:












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Pages River at Blandford Gauge Location

The Pages River at Blandford gauge is one ofthe key sites for analysing the effects ofstreamflow for the proposed mine at ‘SouthBickham’. While the proposed mine is notwithin its drainage area, the gauge is locatedjust upstream of the mine and thus it isrepresentative of flow conditions near themine.

Much of the catchment consists of naturalcatchment, native pasture and irrigatedpasture.

The catchment delineated in blue on the mapwas derived using the 9-second DEM.

Total area of the catchment is ~303 km2.

Pages River at Blandford Gauge Location

Figure 7:

Image Source: Google Maps












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Pages River at Blandford: Comparison of Flow Statistics

Within +/-5% Within 5-20% Great than 20%

Using information obtained from the NSW Department of Environment, Climate Change and Water (http://waterinfo.nsw.gov.au/river-provisional-sites.shtml), FrOG Tech analysed average daily flowinformation from June 1960 (first full month of data) to October 2009 (last full month of data). The results are shown below and are compared to the analysis found in Appendix 18 – Surface WaterQuality and Flow Data. Data was accessed 17 November 2009.

Data used for analysis: The two tables are superficially similar, but 22% of values (pink boxes) differ by over 20% and 33% differ from each other by between 5 to 20% (FrOG Tech/Bickham WMP). It isexpected that there be some small differences between the two datasets as the FrOG Tech analysed data is about 1 year longer. However, it is not clear why there are substantial differences as shownin the bottom chart.

NB: There is significant missing data in the record. If a month was missing more than 10% of its record, itwas not included in the analysis. Similarly, if a year was missing more than 2 months data, it was notincluded in the analysis. Even if the missing data were used, the differences still exist.

FrOG Tech Analysis

January February March April May June July August September October November December Annual

Min 51 32 56 32 64 23 24 0 9 20 26 10 1,302

Average 7,014 2,617 1,855 1,297 2,646 2,509 4,164 4,565 2,791 3,459 3,577 2,666 36,906

Max 60,139 33,089 22,968 17,498 24,779 25,590 63,481 34,700 12,831 35,297 52,154 38,259 145,008

10%ile 129 101 114 104 110 84 139 186 185 254 190 221 4,867

50%ile 634 414 772 342 325 645 1,555 2,894 1,561 1,481 1,357 715 18,594

90%ile 25,556 5,131 3,411 2,806 8,765 5,882 7,779 8,200 7,762 8,194 7,163 4,883 83,432

Bickham Water Management Plan (Appendix 18 - page 7)


Min 52 31 56 32 63 46 51 32 49 61 0 10 1,302

Average 6,928 2,926 1,957 1,567 2,646 2,538 5,032 5,896 2,991 3,476 3,445 3,022 39,685

Max 59,823 33,383 23,972 17,555 26,159 26,014 78,046 60,457 19,456 31,433 67,464 57,100 163,957

10%ile 127 102 116 107 113 90 151 193 189 225 100 227 3,687

50%ile 594 497 609 339 410 791 1,898 3,001 1,578 1,553 1,089 757 21,426

90%ile 26,240 10,418 3,593 2,605 9,213 5,722 9,202 8,930 7,815 8,257 6,066 512 92,088

Analysis of difference (FT/BWMP)


Min 99% 103% 100% 99% 101% 51% 47% 2% 19% 32% N/A 101% 100%

Average 101% 89% 95% 83% 100% 99% 83% 77% 93% 100% 104% 88% 93%

Max 101% 99% 96% 100% 95% 98% 81% 57% 66% 112% 77% 67% 88%

10%ile 102% 99% 99% 97% 97% 93% 92% 97% 98% 113% 190% 97% 132%

50%ile 107% 83% 127% 101% 79% 82% 82% 96% 99% 95% 125% 94% 87%

90%ile 97% 49% 95% 108% 95% 103% 85% 92% 99% 99% 118% 954% 91%

Pages River at Blandford

Table 1:



http://waterinfo.nsw.gov.au/river-provisional-sites.shtml
























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Pages River at Gundy Gauge Location

The Pages River at Gundy gauge includeswithin its catchment the proposed mine at‘South Bickham’. The Gundy gauge site alsoincludes Camerons Gorge.

Much of the catchment consists of naturalcatchment, native pasture and irrigatedpasture.



Pages River at Gundy Gauge Location

Figure 8:













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Pages River at Gundy: Flow Statistics

Using information obtained from the NSW Department of Environment, Climate Change and Water (http://waterinfo.nsw.gov.au/river-provisional-sites.shtml), FrOG Tech analysed average daily flowinformation from October 1958 (first full month of data) to October 2009 (last full month of data). There are no comparison results as the Gundy Gauge was not included in Appendix 18 - Surface WaterQuality and Flow Data. Data was accessed 17 November 2009.


FrOG Tech Analysis


Min 0 3 2 1 1 0 53 20 80 14 19 2 461

Average 10,596 7,421 3,812 3,094 4,639 5,700 8,524 7,690 6,022 4,243 3,703 3,574 62,262

Max 119,516 108,688 62,097 33,409 53,429 35,563 81,493 53,387 35,754 19,717 27,204 21,068 256,070

10%ile 85 74 31 13 18 290 400 247 249 202 154 155 8,570

50%ile 1,334 1,069 911 618 655 1,852 2,993 4,209 3,617 2,528 2,434 1,876 37,269

90%ile 37,156 15,227 7,041 8,789 12,306 17,940 18,693 18,099 12,605 9,104 6,457 9,352 146,109

Pages River at Gundy

Table 2:



























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Kingdon Ponds Creek at Parkville Gauge Location

The Kingdon Ponds Creek at Parkville gaugeincludes within its catchment part of theproposed mine at ‘South Bickham'.

Most of the catchment consists of nativepasture and irrigated pasture.



Kingdon Ponds Creek at Parkville Gauge Location

Figure 9:













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Kingdon Ponds Creek at Parkville: Comparison of Flow Statistics


Using information obtained from the NSW Department of Environment, Climate Change and Water (http://waterinfo.nsw.gov.au/river-provisional-sites.shtml), FrOG Tech analysed average daily flowinformation from June 1972 (first full month of data) to October 2009 (last full month of data). The results are shown below and are compared to the analysis found in Appendix 18 – Surface WaterQuality and Flow Data. Data was accessed 17 November 2009.

Data used for analysis: The two tables are superficially similar, but 14% of values (pink boxes) differ by over 20% and 15% differ from each other by between 5 to 20% (FrOG Tech/Bickham WMP). It isexpected that there be some small differences between the two datasets as the FrOG Tech analysed data is about 1 year longer. However, it is not clear why there are substantial differences as shownin the bottom chart.


FrOG Tech Analysis


Min 0 0 0 0 0 0 0 0 0 0 0 0 0

Average 2,139 365 1,283 222 758 964 917 582 468 406 932 386 9,547

Max 36,750 3,308 26,643 1,257 11,108 13,886 11,699 7,205 3,877 1,554 15,042 4,033 49,931

10%ile 0 0 0 0 1 40 34 29 17 5 2 0 747

50%ile 135 136 137 120 169 219 182 290 276 240 235 182 4,743

90%ile 1,969 905 1,198 473 1,039 2,123 1,981 781 970 1,334 1,227 667 29,702

Bickham Water Management Plan (Appendix 18 - page 9)


Min 0 0 0 0 0 0 0 0 0 0 0 0 0

Average 1,174 735 942 205 669 742 907 585 462 405 858 375 8,568

Max 16,660 12,962 14,538 1,136 10,457 6,829 11,847 7,203 3,916 1,640 15,124 4,284 31,099

10%ile 0 0 0 0 0 39 33 28 18 4 1 0 815

50%ile 129 165 140 119 169 216 177 290 276 242 189 179 4,556

90%ile 1,880 1,153 1,258 476 960 2,150 1,938 795 979 1,341 1,120 656 25,989

Analysis of difference (FT/BWMP)


Min N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/AAverage 182% 50% 136% 108% 113% 130% 101% 100% 101% 100% 109% 103% 111%

Max 221% 26% 183% 111% 106% 203% 99% 100% 99% 95% 99% 94% 161%

10%ile N/A N/A N/A N/A N/A 102% 102% 104% 95% 124% 186% N/A 92%

50%ile 104% 82% 98% 101% 100% 101% 103% 100% 100% 99% 124% 101% 104%

90%ile 105% 78% 95% 99% 108% 99% 102% 98% 99% 100% 110% 102% 114%

Kingdon Ponds Creek at Parkville

Table 3:



























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A full evaluation of the potential impacts on Pages River and Kingdon Ponds Creek

Catchment under stress:The current flow regime in both Pages River and Kingdon Ponds Creek have significantlyaltered since the start of record keeping. (see Pages 22-25)

• Pages River at Blandford: 55.3 ML/day average decrease in flow• Pages River at Gundy: 57.6 ML/day average decrease in flow• Kingdon Ponds Creek at Parkville: 36.5 ML/day average decrease in flow

Increase in no flow days:The introduction of the mine will decrease the volume of baseflow in Pages River by 220KL/day and in Kingdon Ponds Creek by 15 KL/day. (see Pages 26-32)

Using the historic record as a basis for comparison, during the maximum decrease inbaseflow (Year 35) the number of historic, no flow days (Daily Flow – Decrease inBaseflow) would increase from:

• Pages River at Blandford: 30 to 96 (if decrease in catchment due to the mine (90 ha)is included no flow days increases from 30 to 175)

• Pages River at Gundy: 123 to 477• Kingdon Ponds Creek at Parkville: 1072 to 1208

In addition, the presence of the mine will also dramatically change flow characteristics inthe all three of the affected catchments. While this effect is primarily seen in the lowerflow percentiles, the effects can be seen up to the median flow statistics (see Tables 5, 7,9).

Potential Impacts

Effects of climate change:Climate change is predicted to decrease streamflow by ~10%. (see Pages 33-39)

During the maximum decrease in baseflow (Year 35) the number of historic no flow days(Daily Flow – Decrease in Baseflow) would increase from:

• Pages River at Blandford: 30 to 693 (if decrease in catchment due to the mine (90ha) is included no flow days increases from 30 to 814)

• Pages River at Gundy: 123 to 1694• Kingdon Ponds Creek at Parkville: 1072 to 1844

Supplemental water inadequate:The proponent plans to supplement any potential baseflow effects for the 25 years ofthe mine plus 2 additional year. However as can be seen on pages 38-41, the negativebaseflow effects will continue for up to 68 years after mining ceases.

Combined effectThe combined effect of climate change, existing stress conditions, the increase in thenumber of no flow days and the inadequate time-scale of water supplementation meanssome existing water users be affected. The full effect on the river system will largelydepend on the amount of rainfall/runoff over the next 100 years. If the rainfall/runoff isrelatively high then the mine will have negligible impact. However, as climate change ispredicted to reduce runoff by 10%, this is unlikely.

Due to the nature of water demand, the longest lasting effects will probably fall uponenvironmental water users. The decrease in flow, particularly during low flows periodscould provide a ‘tipping point’ beyond which the ecology of the river can not easilyreturn.












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CATCHMENT AT RISK

Catchment At Risk












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Pages River at Blandford: Catchment at risk

Using information obtained from the NSW Department of Environment, Climate Changeand Water (http://waterinfo.nsw.gov.au/river-provisional-sites.shtml), FrOG Techanalysed average daily flow information from January 1961 (first full year of data) toOctober 2009 (last full month of data).

The figure to the right compares the relationship between “natural” conditions (taken asbeing equal to a regression line drawn through the first 10 years of data) and the“observed relationship”.

The figure show that the observed relationship differs significantly from “naturalconditions” and is getting worse over time.

The cumulative change as of 2006 (last year of rainfall data) is 2332 mm or 706.7 GL(assuming a catchment of 303 km2, or 20.2 GL/yr (55.3 ML/day) since 1971.

The decrease in streamflow is due to a myriad of reasons such as changes in landuse,increase in the number of farm dams, and direct wateruse from the river andgroundwater.


Figure 10:



























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Pages River at Gundy: Catchment at risk



The figure show that the observed relationship differs significantly from “naturalconditions” and while there has been a lot a of variability, the observed relationship isgetting worse over time.

The cumulative change as of 2006 (last year of rainfall data) is 725.4 mm or 778.2 GL(assuming a catchment of 1072.8 km2, or 21 GL/yr (57.6 ML/day) since 1969. Most of thedecrease in streamflow probably comes from Pages River (see Pages River at Blandford)rather than the Isis River.



Figure 11:



























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Kingdon Ponds Creek at Parkville: Catchment at risk



The figure show that the observed relationship differs significantly from “naturalconditions” and while there has been a lot a of variability, the observed relationship isgetting worse over time.

The cumulative change as of 2006 (last year of rainfall data) is 1701.2 mm or 306.1 GL(assuming a catchment of 179.1 km2, or 13.3 GL/yr (36.5 ML/day) since 1983.



Figure 12:



























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INCREASE IN NO

FLOW DAYS

Increase In No Flow Days












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Pages River at Blandford: Increase of no-flow days


Table 4, shows the number of no flows days modelled for the entire historic streamflowrecord under various scenarios.

• Natural: Historic no-flow days

• Mine Baseflow only: No-flow days during maximum baseflow reduction (220KL/day) subtracted from each day’s flow

• Mine Baseflow decrease double: No-flow days of maximum baseflow reduction isdoubled (440 KL/day) subtracted from each day’s flow.

• Mine Baseflow and Decreased Catchment: No-flow days during maximum baseflowreduction (220 KL/day) and decreased catchment (90 ha or 0.3% of total catchment)due to the presence of the mine (Average annual reduction of 108 ML/yr or ~300KL/day). Total reduction of 520 KL/day.

As can be seen in the modelled scenarios the presence of the Bickham Mine wouldincrease by 3-5 times over the natural scenario.

If the effects of climate change are included then in all but the wettest years Pages Riverwill not flow for large parts of the year.

Year Natural

Mine Baseflow

only

Mine Baseflow

decrease

double

Mine Baseflow

and Decreased

Catchment

1961 0 0 0 0

1962 0 0 0 0

1963 0 0 0 0

1964 0 0 0 0

1965 0 0 0 0

1966 0 0 0 0

1967 0 0 0 3

1968 0 0 0 0

1970 0 0 0 0

1971 0 0 0 0

1972 0 0 0 0

1973 0 0 0 0

1974 0 0 0 0

1975 0 0 0 0

1976 0 0 0 0

1977 0 0 0 0

1985 0 0 0 0

1986 0 0 0 0

1987 0 0 0 0

1988 0 0 0 0

1989 0 0 0 0

1994 0 0 0 0

1995 0 0 1 4

1996 0 0 0 0

1998 0 0 0 0

1999 0 0 0 0

2000 0 0 0 0

2001 0 0 0 0

2002 22 62 92 104

2003 0 0 0 0

2004 0 0 0 0

2005 0 0 0 0

2006 2 15 23 24

2007 6 19 35 40

2008 0 0 0 0

2009 0 0 0 0

Total 30 96 151 175


Table 4:



























ABN: 29 129 411 981

Pages River at Blandford: Comparison of Flow Statistics 2


Changes in flow statistics due to baseflow reduction and decrease of catchment.

Using information obtained from the NSW Department of Environment, Climate Change and Water (http://waterinfo.nsw.gov.au/river-provisional-sites.shtml), FrOG Tech analysed average daily flowinformation from June 1960 (first full month of data) to October 2009 (last full month of data). The results are shown below and are compared to the decrease in streamflow due to the decrease inbaseflow (220 KL/day) and catchment (300 KL/day) due to the proposed Bickham Mine. Data was accessed 17 November 2009.

The results show that there will be a significant change in flow behaviour during the lowest flow percentiles.


Historic


Min 51 32 56 32 64 23 24 0 9 20 26 10 1,302

Average 7,014 2,617 1,855 1,297 2,646 2,509 4,164 4,565 2,791 3,459 3,577 2,666 36,906

Max 60,139 33,089 22,968 17,498 24,779 25,590 63,481 34,700 12,831 35,297 52,154 38,259 145,008

10%ile 129 101 114 104 110 84 139 186 185 254 190 221 4,867

50%ile 634 414 772 342 325 645 1,555 2,894 1,561 1,481 1,357 715 18,594

90%ile 25,556 5,131 3,411 2,806 8,765 5,882 7,779 8,200 7,762 8,194 7,163 4,883 83,432

With maximum baseflow and decrease in catchment


Min 35 17 40 16 47 8 8 0 0 3 10 0 1,113

Average 6,998 2,602 1,839 1,281 2,630 2,494 4,148 4,549 2,775 3,443 3,561 2,650 36,721

Max 60,123 33,074 22,952 17,483 24,763 25,574 63,465 34,683 12,815 35,280 52,138 38,243 144,825

10%ile 113 86 98 89 93 68 123 170 169 238 174 205 4,696

50%ile 618 400 755 326 309 630 1,539 2,878 1,545 1,465 1,341 699 18,423

90%ile 25,540 5,115 3,395 2,791 8,749 5,866 7,762 8,184 7,747 8,178 7,147 4,867 83,242

Analysis of difference (original/modif ied)


Min 146% 183% 140% 198% 134% 298% 304% N/A N/A 574% 253% N/A 117%

Average 100% 101% 101% 101% 101% 101% 100% 100% 101% 100% 100% 101% 101%

Max 100% 100% 100% 100% 100% 100% 100% 100% 100% 100% 100% 100% 100%

10%ile 114% 117% 116% 118% 117% 123% 113% 109% 109% 107% 109% 108% 104%

50%ile 103% 104% 102% 105% 105% 102% 101% 101% 101% 101% 101% 102% 101%

90%ile 100% 100% 100% 101% 100% 100% 100% 100% 100% 100% 100% 100% 100%


Table 5:



























ABN: 29 129 411 981

Pages River at Gundy: Increase of no-flow days



• Natural: Historic no-flow days• Mine Baseflow only: No-flow days during maximum baseflow reduction (220

KL/day) subtracted from each day’s flow• Mine Baseflow decrease double: No-flow days of maximum baseflow reduction is

doubled (440 KL/day) subtracted from each day’s flow.

As can be seen in the modelled scenarios the presence of the Bickham Mine wouldincrease by about 4 times over the natural scenario.


Year Natural Mine

Mine Baseflow

decrease

double

1959 6 6 7

1960 0 0 0

1961 0 0 0

1962 0 0 0

1963 0 0 0

1964 0 0 0

1965 1 6 12

1966 0 89 143

1967 4 5 5

1968 0 0 0

1969 0 0 0

1970 0 0 0

1971 0 0 0

1972 0 0 0

1973 0 0 0

1974 0 0 0

1975 0 0 0

1976 0 9 12

1978 0 0 0

1979 0 0 0

1980 0 0 1

1981 21 35 53

1982 0 0 25

1983 0 0 26

1984 0 0 0

1985 0 0 0

1986 0 0 0

1987 0 0 0

1988 0 0 0

1989 0 0 5

1990 0 0 0

1991 0 0 2

1992 13 15 15

1993 0 0 0

1994 0 8 42

1995 29 119 131

2003 0 0 1

2004 0 16 24

2005 0 37 52

2006 9 98 143

2007 51 140 147

2008 0 0 0

2009 0 0 0

Total 123 477 679


Table 6:



























ABN: 29 129 411 981

Pages River at Gundy: Flow Statistics 2

Changes in flow statistics due to baseflow reduction.

Using information obtained from the NSW Department of Environment, Climate Change and Water (http://waterinfo.nsw.gov.au/river-provisional-sites.shtml), FrOG Tech analysed average daily flowinformation from October 1958 (first full month of data) to October 2009 (last full month of data). The results are not compared as other values were not included in Appendix 18 - Surface WaterQuality and Flow Data. Data was accessed 17 November 2009.

The results show that there will be a significant change in flow behaviour during the lowest flow percentiles.



Historic


Min 0 3 2 1 1 0 53 20 80 14 19 2 461

Average 10,596 7,421 3,812 3,094 4,639 5,700 8,524 7,690 6,022 4,243 3,703 3,574 62,262

Max 119,516 108,688 62,097 33,409 53,429 35,563 81,493 53,387 35,754 19,717 27,204 21,068 256,070

10%ile 85 74 31 13 18 290 400 247 249 202 154 155 8,570

50%ile 1,334 1,069 911 618 655 1,852 2,993 4,209 3,617 2,528 2,434 1,876 37,269

90%ile 37,156 15,227 7,041 8,789 12,306 17,940 18,693 18,099 12,605 9,104 6,457 9,352 146,109

With maximum baseflow decrease


Min 0 0 0 0 0 0 39 7 67 1 5 0 301

Average 10,582 7,408 3,799 3,081 4,626 5,687 8,510 7,677 6,009 4,229 3,690 3,560 62,106

Max 119,502 108,675 62,084 33,395 53,416 35,550 81,480 53,373 35,741 19,704 27,190 21,054 255,910

10%ile 71 62 18 0 8 276 386 233 236 188 141 141 8,409

50%ile 1,320 1,057 897 605 642 1,838 2,980 4,195 3,603 2,515 2,421 1,862 37,108

90%ile 37,143 15,214 7,027 8,776 12,292 17,929 18,680 18,085 12,592 9,090 6,444 9,339 145,948



Min N/A N/A N/A N/A N/A N/A 135% 305% 120% 1718% 348% N/A 153%

Average 100% 100% 100% 100% 100% 100% 100% 100% 100% 100% 100% 100% 100%

Max 100% 100% 100% 100% 100% 100% 100% 100% 100% 100% 100% 100% 100%

10%ile 119% 120% 177% N/A 228% 105% 104% 106% 106% 107% 109% 110% 102%

50%ile 101% 101% 102% 102% 102% 101% 100% 100% 100% 101% 101% 101% 100%

90%ile 100% 100% 100% 100% 100% 100% 100% 100% 100% 100% 100% 100% 100%


Table 7:



























ABN: 29 129 411 981

Kingdon Ponds Creek at Parkville: Increase of no-flow days



• Natural: Historic no-flow days• Mine Baseflow only: No-flow days during maximum baseflow reduction (15 KL/day)

subtracted from each day’s flow• Mine Baseflow decrease double: No-flow days of maximum baseflow reduction is

doubled (30 KL/day) subtracted from each day’s flow.

As can be seen in the modelled scenarios the presence of the Bickham Mine wouldincrease by about 13% over the natural scenario.


Year Natural Mine

Mine Baseflow

decrease

double

1973 0 0 0

1974 0 0 0

1975 0 0 0

1976 0 0 0

1977 0 0 0

1978 0 0 0

1979 0 0 0

1980 13 16 38

1981 104 112 119

1982 0 0 0

1983 64 94 97

1984 0 0 0

1985 0 0 0

1986 0 0 0

1987 0 0 0

1988 0 0 0

1993 0 0 0

1994 0 0 0

1995 0 0 0

1996 0 0 0

1997 0 0 0

1998 0 0 0

1999 0 0 0

2000 0 0 0

2001 0 0 0

2002 51 68 82

2003 354 365 365

2004 72 72 72

2005 51 90 155

2006 205 232 238

2007 158 159 159

2008 0 0 0

2009 0 0 0

Total 1072 1208 1325


Table 8:



























ABN: 29 129 411 981

Kingdon Ponds Creek at Parkville: Comparison of Flow Statistics 2


Changes in flow statistics due to baseflow reduction.

Using information obtained from the NSW Department of Environment, Climate Change and Water (http://waterinfo.nsw.gov.au/river-provisional-sites.shtml), FrOG Tech analysed average daily flowinformation from June 1972 (first full month of data) to October 2009 (last full month of data). The results are shown below and are compared to the decrease in streamflow due to the decrease inbaseflow (15 KL/day) due to the proposed Bickham Mine. Data was accessed 17 November 2009.

The results show that there will only be a small change to flow statistics.


Historic


Min 0 0 0 0 0 0 0 0 0 0 0 0 0

Average 2,139 365 1,283 222 758 964 917 582 468 406 932 386 9,547

Max 36,750 3,308 26,643 1,257 11,108 13,886 11,699 7,205 3,877 1,554 15,042 4,033 49,931

10%ile 0 0 0 0 1 40 34 29 17 5 2 0 747

50%ile 135 136 137 120 169 219 182 290 276 240 235 182 4,743

90%ile 1,969 905 1,198 473 1,039 2,123 1,981 781 970 1,334 1,227 667 29,702

With maximum baseflow decrease


Min 0 0 0 0 0 0 0 0 0 0 0 0 0

Average 2,139 364 1,282 221 758 963 916 582 468 405 932 385 9,541

Max 36,749 3,308 26,643 1,257 11,108 13,886 11,698 7,204 3,877 1,553 15,042 4,032 49,926

10%ile 0 0 0 0 0 40 33 29 17 5 1 0 742

50%ile 134 136 137 120 169 218 182 289 275 240 235 181 4,738

90%ile 1,969 904 1,198 473 1,039 2,123 1,981 781 969 1,334 1,227 666 29,697




Max 100% 100% 100% 100% 100% 100% 100% 100% 100% 100% 100% 100% 100%

10%ile N/A N/A N/A N/A N/A 101% 101% 102% 103% N/A 132% N/A 101%

50%ile 100% 100% 100% 100% 100% 100% 100% 100% 100% 100% 100% 100% 100%

90%ile 100% 100% 100% 100% 100% 100% 100% 100% 100% 100% 100% 100% 100%


Table 9:



























ABN: 29 129 411 981

EFFECTS OF

CLIMATE CHANGE

Effects Of Climate Change












ABN: 29 129 411 981

Pages River at Blandford: Increase of no-flow days due to climate change



• Climate: No-flow days due to the decrease in runoff due to climate change (for thepurpose of modelling the median daily runoff for each day was calculated and thendecreased by 10%).

• Climate Change and Mine Baseflow only: No-flow days due to the combination ofclimate change (10% decrease in runoff) and the maximum decrease in baseflow(220 KL/day).

• Climate Change and Mine Baseflow and Decreased Catchment: No-flow days dueto the combination of climate change (10% decrease in runoff) and the maximumbaseflow reduction and decreased catchment due to mine (520 KL/day).

As can be seen in the modelled scenarios the presence of the Bickham Mine wouldincrease by over 3-5 times over the natural scenario.


Year Climate

Climate Change

and Mine

Baseflow only

Climate Change

and Mine

Baseflow and

Decreased

Catchment

1961 0 0 0

1962 0 0 0

1963 0 0 0

1964 0 0 0

1965 4 8 22

1966 59 73 84

1967 28 35 41

1968 0 0 0

1970 0 0 0

1971 0 0 0

1972 2 3 4

1973 1 2 3

1974 0 0 0

1975 0 0 0

1976 0 0 0

1977 0 0 0

1985 0 0 0

1986 4 6 15

1987 0 0 0

1988 0 0 0

1989 0 0 4

1994 34 47 60

1995 48 68 91

1996 0 0 0

1998 0 0 0

1999 0 0 1

2000 2 6 8

2001 0 0 0

2002 189 192 195

2003 17 23 39

2004 2 4 6

2005 0 0 0

2006 139 152 162

2007 66 74 79

2008 0 0 0

2009 0 0 0

Total 595 693 814


Table 10:



























ABN: 29 129 411 981

Pages River at Blandford: Comparison of Flow Statistics 3


Changes in flow statistics due to baseflow reduction, decrease in catchment and climate change.

Using information obtained from the NSW Department of Environment, Climate Change and Water (http://waterinfo.nsw.gov.au/river-provisional-sites.shtml), FrOG Tech analysed average daily flowinformation from June 1960 (first full month of data) to October 2009 (last full month of data). The results are shown below and are compared to potential changes from climate change (10% decreasein runoff), the decrease in streamflow due to the decrease in baseflow and catchment due to the proposed Bickham Mine. Data was accessed 17 November 2009.

The results show that there will be a significant change in flow behaviour during the lowest flow percentiles and median flow.


Historic


Min 51 32 56 32 64 23 24 0 9 20 26 10 1,302

Average 7,014 2,617 1,855 1,297 2,646 2,509 4,164 4,565 2,791 3,459 3,577 2,666 36,906

Max 60,139 33,089 22,968 17,498 24,779 25,590 63,481 34,700 12,831 35,297 52,154 38,259 145,008

10%ile 129 101 114 104 110 84 139 186 185 254 190 221 4,867

50%ile 634 414 772 342 325 645 1,555 2,894 1,561 1,481 1,357 715 18,594

90%ile 25,556 5,131 3,411 2,806 8,765 5,882 7,779 8,200 7,762 8,194 7,163 4,883 83,432

With climate change, maximum baseflow and decrease in catchment


Min 0 0 2 0 17 0 0 0 0 0 0 0 394

Average 6,961 2,568 1,802 1,253 2,600 2,450 4,060 4,447 2,660 3,361 3,492 2,603 36,020

Max 60,086 33,038 22,914 17,454 24,732 25,530 63,377 34,580 12,699 35,198 52,069 38,196 144,119

10%ile 76 52 61 60 63 24 35 68 54 154 105 157 4,048

50%ile 581 366 718 298 278 585 1,450 2,775 1,429 1,382 1,272 651 17,739

90%ile 25,503 5,079 3,358 2,763 8,718 5,822 7,674 8,082 7,630 8,094 7,078 4,820 82,522



Min N/A N/A 2297% N/A 377% N/A N/A N/A N/A N/A N/A N/A 331%

Average 101% 102% 103% 103% 102% 102% 103% 103% 105% 103% 102% 102% 102%

Max 100% 100% 100% 100% 100% 100% 100% 100% 101% 100% 100% 100% 101%

10%ile 170% 193% 188% 172% 174% 349% 399% 275% 341% 165% 181% 141% 120%

50%ile 109% 113% 107% 115% 117% 110% 107% 104% 109% 107% 107% 110% 105%

90%ile 100% 101% 102% 102% 101% 101% 101% 101% 102% 101% 101% 101% 101%


Table 11:



























ABN: 29 129 411 981

Pages River at Gundy: Increase of no-flow days

due to climate change



• Climate: No-flow days due to the decrease in runoff due to climate change (for thepurpose of modelling the median daily runoff for each day was calculated and thendecreased by 10%)

• Climate Change and Mine Baseflow only: No-flow days due to the combination ofclimate change (10% decrease in runoff) and the maximum decrease in baseflow(220 KL/day).

As can be seen in the modelled scenarios the presence of the Bickham Mine wouldincrease by about 4 times over the natural scenario.


Year Climate

Climate Change

and Mine

1959 8 8

1960 0 0

1961 0 0

1962 0 0

1963 0 0

1964 0 0

1965 54 55

1966 201 205

1967 50 52

1968 0 0

1969 0 0

1970 0 0

1971 0 0

1972 5 7

1973 15 17

1974 13 17

1975 49 52

1976 17 17

1978 0 0

1979 1 2

1980 175 184

1981 96 101

1982 129 134

1983 97 97

1984 0 0

1985 0 0

1986 4 7

1987 17 19

1988 0 0

1989 27 28

1990 0 0

1991 28 30

1992 19 19

1993 0 0

1994 101 102

1995 183 185

2003 24 28

2004 38 40

2005 89 94

2006 336 341

2007 169 169

2008 0 0

2009 9 11

Total 1636 1694


Table 12:



























ABN: 29 129 411 981

Pages River at Gundy: Flow Statistics 3

Changes in flow statistics due to baseflow reduction and climate change.

Using information obtained from the NSW Department of Environment, Climate Change and Water (http://waterinfo.nsw.gov.au/river-provisional-sites.shtml), FrOG Tech analysed average dailyflow information from October 1958 (first full month of data) to October 2009 (last full month of data). The results are not compared as other values were not included in Appendix 18 - SurfaceWater Quality and Flow Data. Data was accessed 17 November 2009.

The results show that there will be a significant change in flow behaviour during the lowest flow percentiles and median flow.



Historic


Min 0 3 2 1 1 0 53 20 80 14 19 2 461

Average 10,596 7,421 3,812 3,094 4,639 5,700 8,524 7,690 6,022 4,243 3,703 3,574 62,262

Max 119,516 108,688 62,097 33,409 53,429 35,563 81,493 53,387 35,754 19,717 27,204 21,068 256,070

10%ile 85 74 31 13 18 290 400 247 249 202 154 155 8,570

50%ile 1,334 1,069 911 618 655 1,852 2,993 4,209 3,617 2,528 2,434 1,876 37,269

90%ile 37,156 15,227 7,041 8,789 12,306 17,940 18,693 18,099 12,605 9,104 6,457 9,352 146,109

With climate change, maximum baseflow decrease


Min 0 0 0 0 0 0 0 0 0 0 0 0 0

Average 10,531 7,358 3,752 3,041 4,583 5,594 8,369 7,540 5,836 4,083 3,566 3,476 60,994

Max 119,451 108,623 62,038 33,355 53,370 35,454 81,339 53,235 35,566 19,557 27,067 20,971 254,772

10%ile 20 12 0 0 0 180 246 95 62 42 17 56 7,272

50%ile 1,269 1,006 851 565 596 1,740 2,839 4,057 3,429 2,370 2,297 1,778 35,971

90%ile 37,091 15,163 6,981 8,736 12,247 17,843 18,539 17,947 12,418 8,945 6,320 9,255 144,809



Min N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A

Average 101% 101% 102% 102% 101% 102% 102% 102% 103% 104% 104% 103% 102%

Max 100% 100% 100% 100% 100% 100% 100% 100% 101% 101% 101% 100% 101%

10%ile 421% 594% N/A N/A N/A 161% 163% 260% 403% 484% 909% 275% 118%

50%ile 105% 106% 107% 109% 110% 106% 105% 104% 105% 107% 106% 106% 104%

90%ile 100% 100% 101% 101% 100% 101% 101% 101% 102% 102% 102% 101% 101%


Table 13:



























ABN: 29 129 411 981

Kingdon Ponds Creek at Parkville: Increase of no-flow days due to climate change

Using information obtained from the NSW Department ofEnvironment, Climate Change and Water(http://waterinfo.nsw.gov.au/river-provisional-sites.shtml), FrOG Techanalysed average daily flow information from January 1973 (first fullyear of data) to October 2009 (last full month of data).

Table 14, shows the number of no flows days modelled for the entirehistoric streamflow record under various scenarios.

• Climate: No-flow days due to the decrease in runoff due toclimate change (for the purpose of modelling the median dailyrunoff for each day was calculated and then decreased by 10%).

• Climate Change and Mine Baseflow only: No-flow days due tothe combination of climate change (10% decrease in runoff) andthe maximum decrease in baseflow (15 KL/day).

As can be seen in the modelled scenarios the presence of theBickham Mine would increase by about 13% over the naturalscenario.

If the effects of climate change are included then in all but thewettest years Pages River will not flow for large parts of the year.

Year Climate

Climate Change

and Mine

1973 0 0

1974 0 0

1975 0 0

1976 0 0

1977 0 0

1978 0 0

1979 0 0

1980 106 107

1981 200 200

1982 9 10

1983 131 131

1984 0 0

1985 0 0

1986 0 0

1987 0 0

1988 0 0

1993 0 0

1994 24 25

1995 0 0

1996 0 0

1997 0 0

1998 0 0

1999 0 0

2000 0 0

2001 0 0

2002 127 127

2003 365 365

2004 72 72

2005 285 286

2006 362 362

2007 159 159

2008 0 0

2009 0 0

Total 1840 1844


Table 14:



























ABN: 29 129 411 981


Changes in flow statistics due to climate change and baseflow reduction.

Using information obtained from the NSW Department of Environment, Climate Change and Water (http://waterinfo.nsw.gov.au/river-provisional-sites.shtml), FrOG Tech analysed average daily flowinformation from June 1972 (first full month of data) to October 2009 (last full month of data). The results are shown below and are compared to the decrease in streamflow due to the decrease inbaseflow (15 KL/day) due to the proposed Bickham Mine. Data was accessed 17 November 2009.

The results show that there will be a moderate decrease in both the 10%ile and median flow statistics.


Historic


Min 0 0 0 0 0 0 0 0 0 0 0 0 0

Average 2,139 365 1,283 222 758 964 917 582 468 406 932 386 9,547

Max 36,750 3,308 26,643 1,257 11,108 13,886 11,699 7,205 3,877 1,554 15,042 4,033 49,931

10%ile 0 0 0 0 1 40 34 29 17 5 2 0 747

50%ile 135 136 137 120 169 219 182 290 276 240 235 182 4,743

90%ile 1,969 905 1,198 473 1,039 2,123 1,981 781 970 1,334 1,227 667 29,702

With climate change, maximum baseflow decrease


Min 0 0 0 0 0 0 0 0 0 0 0 0 0

Average 2,126 352 1,270 209 743 945 900 563 445 384 915 369 9,349

Max 36,736 3,295 26,631 1,244 11,092 13,868 11,682 7,185 3,853 1,532 15,026 4,016 49,727

10%ile 0 0 0 0 0 21 17 9 0 0 0 0 571

50%ile 121 123 125 107 153 200 165 270 252 218 218 164 4,540

90%ile 1,956 892 1,186 460 1,024 2,105 1,964 761 946 1,312 1,210 650 29,499




Max 100% 100% 100% 101% 100% 100% 100% 100% 101% 101% 100% 100% 100%

10%ile N/A N/A N/A N/A N/A 187% 203% 316% N/A N/A N/A N/A 131%

50%ile 111% 110% 110% 112% 110% 109% 110% 107% 109% 110% 108% 111% 104%

90%ile 101% 101% 101% 103% 102% 101% 101% 103% 102% 102% 101% 103% 101%

Kingdon Ponds Creek at Parkville: Comparison of Flow Statistics 3


Table 15:



























ABN: 29 129 411 981

SUPPLEMENTAL

FLOW INADEQUATE

Supplemental Flow Inadequate












ABN: 29 129 411 981

Pages River at Blandford: Years to flow back to normal

The maximum decrease in baseflowoccurs at year 35 (10 years after miningceases).

During peak decrease of baseflow (220KL/day), historic no flow days wouldhave increased from 30 to 96 (seepages 25-26).

At year 65 (40 years after miningceases) the decrease in baseflow dueto the mine would still be 63.

At year 78 (53 years after miningceases) the decrease in baseflow dueto the mine would be 46.

It is not until about year 93 (68 yearsafter mining ceases) that the decreasein baseflow due to the mine will causenegligible impact.


Figure 13:












ABN: 29 129 411 981

Pages River at Gundy: Years to flow back to normal




At year 78 (53 years after miningceases) the decrease in baseflow dueto the mine would be 239.

It is not until about year 93 (68 yearsafter mining ceases) that the decreasein baseflow due to the mine will causenegligible impact.


Figure 14:












ABN: 29 129 411 981

Kingdon Ponds Creek at Parkville: Years to flow back to normal




Baseflow in the Kingdon Ponds Creek ismodelled to not return to normal evenafter 100 years of recovery, but stay ~8KL/day. This would equate 1165 noflow days (8% increase over normal).


Figure 15:












ABN: 29 129 411 981

In order of potential effect, the major water, risk factors for the Bickham area are:

1. Excessive baseflow impacts to either the Pages River or Kingdon Ponds Creek

2. Excessive inflow rate to pit

3. pH changes from any potential acid mine drainage and whether this couldadversely impact on groundwater/surface water quality

4. Drawdown interferencewith existing water supply bores, wells or soaks

5. The groundwater model is a fairly simplistic both structurally and stratigraphically

6. Direct leakage of Pages River to the pit

7. Very low groundwater inflows to pit

8. Interception of saline groundwater that might significantly elevate the salinity orlower the pH of the groundwater discharge into the pit or the dewatering bores

9. Salinity of in-pit water post-mining and whether this could adversely impactgroundwater quality around the pit

10. Salinity of stormwater infiltrating through the out-of-pit dump and whether thiscould adversely impact on groundwater/surface water quality

11. Reactivation of faults and fractures due to removal of rocks due to mining.

12. Effects of increased recharge due to irrigation of the excess mine water notincluded in the groundwater model

Conclusions

Conclusions



evaluation of the bickham coal mine water management planbcag.com.au/submissions/frogtech for water...

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