Tailings Deposition into Open Pit Consolidation Modelling · 2017-03-21 · Tailings Deposition...

McArthur River Mine

Overburden Management Project

Draft Environmental Impact Statement

ACAppendix AC

Tailings Deposition intoOpen Pit Consolidation Modelling

3 November 2016

Jamie Hacker

McArthur River Mining

PO Box 36821

Winnellie NT 0821

Our ref: 32/17476/05 65221 Your ref:

Dear Jamie

Tailings Deposition into Open Pit

Consolidation Modelling and Deposition Concept

1 Introduction

McArthur River Mine (MRM) is planning to utilise the existing pit void, approximately 385 m deep, for long

term storage of the tailings and Potential Acid Forming (PAF) waste rock at closure. Tailings are

currently stored at the out-of-pit Tailings Storage Facility (TSF) and will be dredged and reprocessed and

the resulting tailings slurry would be pumped to the pit void for in-pit disposal. The in-pit deposition will

be undertaken over a 10-year period at a production rate of 10.5 Mtpa.

This letter report summarises the results of consolidation analyses undertaken for the in-pit disposal of

the tailings under short-term and long-term conditions.

To assist with the analysis, MRM has provided the ultimate pit design, inclusive of the In-Pit Dump (IPD),

which is a volume of waste rock that MRM intend to place into the pit during the last 5 to 6 years of mine

operation – i.e. before the tailings deposition commences.

In addition to the IPD, MRM has also advised that they intend to co-dispose 7.5MT of PAF waste rock

into the pit during the second year of tailings deposition. Waiting until Year 2 – by which point the pit will

be partially filled with tailings – will help to reduce the haulage distance for the PAF waste rock.

The rate of rise is anticipated to be very high during initial years (e.g. estimated 96 to 98 metre rise in

Year 1) and gradually decreases to 5 to 10 m per year during final years.

2 Objectives

The objectives of the consolidation analyses are to

to estimate how tailings deposited into the MRM open pit would consolidate under self-weight

during and after deposition

to estimate consolidation water and rate of release into the pond in the pit

to estimate consolidation time after completion of deposition at closure

to estimate the dry density of deposited tailings and the storage volumes of tailings during and

after deposition under long-term conditions

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3 Scope of Work

Desktop study only, using available information on tailings properties and GHD’s experience in

tailings consolidation properties from similar tailings.

Review KCB groundwater model with regards to the forecast groundwater recharge with time

following the cessation of mining activities.

Review available geotechnical information on the tailings to establish model parameters.

Model the consolidation of the tailings under self-weight during the deposition cycles and water

losses through drainage boundaries using a one dimensional self-weight consolidation program.

Model consolidation to determine volume of water released to the pit.

Estimate water loss due to evaporation.

Estimate the dry density profile of the tailings and the storage capacity of the pit void, including the

elevation of the tailings surface is to reach during deposition cycles.

Make recommendations on next steps to enabling more detailed estimates to be made, including

further testing of tailings.

4 Large Deformation Modelling of Tailings Consolidation under Self-Weight

4.1 Tailings Consolidation and Drying

After deposition discharge, tailings slurry with low solids content will bleed due to settling of the tailings

particles. Following settling, the tailings will undergo self-weight consolidation and consolidation water

will be expelled out of the tailings matrix due to the volume change of the tailings during consolidation.

The rate of water coming to the surface from self-weight consolidation is generally greater than

evaporation rates due to high moisture content. After initial consolidation, evaporation starts to have an

effect on the void ratio when the initial large volume change due to consolidation is diminishing.

4.2 Initial consolidation of tailings – large deformation modelling

During self-weight consolidation, tailings will undergo large deformations because the initial effective

stress is low and the void ratio is high in the early stage of development of the tailings matrix. During

tailings deposition, the drainage path increases as the thickness of the deposit gradually increases.

Therefore, for self-weight consolidation problems, the conventional Terzaghi consolidation theory

becomes invalid due to the inherent assumption of infinitesimal strains and fixed drainage paths. Gibson

et al. (1967) developed a finite strain consolidation theory for self-weight consolidation and established

the governing differential equation. Li et al. (2012) developed an approach to model self-weight

consolidation using analytical solutions solved for Gibson consolidation theory. It was proposed to use

the following power function to capture high nonlinearity due to initial large volume change at high void

ratio for tailings:

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e = AB

where:

e = void ratio.

' = effective stress.

A, B = material constants

The material constants A and B can be obtained from fitting the void ratio - logarithm effective stress

curve using the above equation.

The modelling approach proposed by Li et al. (2012) was developed specifically for tailings consolidation

during deposition at rate of rise and consolidation after deposition. This approach was adopted to model

the consolidation behaviour of the MRM tailings during in-pit deposition.

5 Assumptions

For the base case considered, the following key assumptions were made in the analyses.

The permeability of the rock at the bottom of the pit and around the pit wall is relatively low in

comparison to the permeability of the tailings. Therefore, it is reasonably assumed that a one-

way drainage to the top will prevail and tailings will consolidate under a one-dimensional

condition.

Tailings and the waste rock will be not comingled.

The volume change of waste rock is negligible.

The additional approximately 100m depth of water on top of the subaqueous tailings would have

negligible effect on the consolidation of the tailings during post deposition periods, because the

tailings are assumed to be essentially saturated throughout the deposit at the end of the

deposition in the final year. The 100 m of water would increase the total stress but will not

change the effective stress in between tailings particles.

The potential evaporation rate was assumed to be the same as that used in the O’Kane report

(2016). The pan factor due to potential reduced sunlight and wind was not assessed in this

study; these could be considered in more detailed future studies.

6 Model Parameters

Two column settling tests were conducted on slurry samples with initial solids content of 55.0% by weight

(ATC Williams, 2014) and the settled dry density was estimated to be 1.17 t/m3 and 1.24 t/m3

respectively. The specific gravity of the tailings is approximately 3.2. The consolidation tests have been

carried out by GHD (2016) and University of Queensland (2016) on tailings samples recovered from the

TSF. Figure 1 summarises the results of the previous consolidation tests. Sample 2 was taken from the

tailings beach with coarser tailings and Sample 5 was taken near the decant pond with finer tailings.

Sample 1 represents an average sample with respect to particle size distribution. Using Eq. 1 to match

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the results of the settling test and consolidation tests, the power function constants A and B were

estimated to be 1.5 and -1.2, respectively.

A coefficient of consolidation of 2.0 m/month was selected based on the average value of the coefficients

of consolidation measured in the laboratories as shown in Figure 2.

Figure 1 Results of Consolidation Tests and Selected Consolidation Curve for in-pit Tailings

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

2

0.1 1 10 100 1000 10000

Vo

id R

atio

Consolidation Pressure (kPa)

Sample (2015) at depth 6.65m Sample 1 Sample 2

Sample 5 Settling tests Selected in-pit tailings

UQ Density 1.7t/m3 UQ Density 1.9t/m3

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Figure 2 Coefficient of Consolidation

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0 100 200 300 400 500 600 700 800

Co

nso

lidat

ion

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effi

cien

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2/m

on

th)

Consolidation Pressure (kPa))

Sample (2015) at depth 6.65m UQ Density 1.7t/m3 UQ Density 1.9t/m3 Average

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7 Modelling Results

7.1 Consolidation During Deposition

The initial consolidation analyses were carried out to predict the elevation of the tailings surface at the

end of each year based on the production of the tailings for in-pit disposal. The tailings surface level was

determined through iterative analyses based on the average dry density of the tailings deposit and the

estimated volume of the tailings at each modelling period. Table 1 summarises the results of the

predicted tailings surface levels and the average dry density for each year.

Table 1 Predicted Dry Density Widths of sections to calculate seepage

Year Stored Dry Mass (tonne)

Dry Density

d (t/m3)

Height from Base* (m)

Elevation MGA94* (m)

Rate of Rise* (m/yr)

Year 1 10,500,000 1.387 96.0 -289.0 96.0

Year 2 21,000,000 1.399 136.0 -248.0 41.0

Year 3 31,500,000 1.415 154.0 -230.0 18.0

Year 4 42,000,000 1.427 169.0 -214.0 16.0

Year 5 52,500,000 1.420 183.0 -200.0 14.0

Year 6 63,000,000 1.445 194.0 -188.0 12.0

Year 7 73,500,000 1.452 204.0 -177.0 11.0

Year 8 84,000,000 1.459 214.0 -167.0 10.0

Year 9 94,500,000 1.464 223.0 -157.0 10.0

Year 10 105,000,000 1.473 227.0 -152.0 5.0

*Note: The levels and heights shown here are based on the pit storage spreadsheet provided by MRM

on 16 Sep 2016 and were the basis of the consolidation modelling. In the attached drawings SK001 to

SK005, GHD has also calculated tailings fill volumes and levels based upon the pit CAD model provided

by MRM on 06 Sep 2016. There are some minor differences between the year-to-year levels shown in

the table above and the attached drawings (on average less than 0.5m per year), which are considered

to be negligible for the current study.

Figure 3 shows the predicted density profile at the end of each operating year. Due to one-way drainage

condition and the relatively high rate of rise of the tailing surface, the tailings in the upper part the pit

would not experience significant consolidation during deposition and the dry density would be constant at

the initial dry density after settling. The tailings in the lower part of the pit will consolidate during

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deposition and the density increases with depth. The degree of consolidation with respect to settlement

ranges from 9.9% at the end of the first year to 33.0% at the end of the last year.

Figure 3 Dry Density Profiles of the Tailings During Deposition

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pth

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dry density (t/m3)

Year 1

Year 2

Year 3

Year 4

Year 6

Year 5

Yaer 7

Year 8

Year 9

Year 10

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7.2 Consolidation Water

Table 2 shows the accumulative consolidation water released to the surface, estimated flow rate and

average flux during the 10 years of the operating period. Figure 4 shows the estimated accumulative

consolidation water, increasing from approximately 0.93 Mm3 in Year 1 to 13,07 Mm3 in Year 10. The

estimated annual average flux from the underlying tailings to the tailings surface ranges from 12.4

mm/day/m2 in Year 1 to 3.7 mm/day/m2 in Year 10.

The average annual potential evaporation rate is approximately 1990 mm/year corresponding to 5.5

mm/day (O’Kane Consultants, 2016). Based on the estimated release rate of consolidation water to the

pit, the tailings are anticipated to be essentially saturated from Year 1 to Year 9 under average weather

conditions. In other words, the rate of tailings water loss due to the evaporation would be at a rate of 5.5

mm/day/m2 under the average weather conditions. The results of the consolidation analysis suggest that

the subaerial deposition would not provide significant advantages with respect to water losses and

volume change of the tailings under the average weather conditions.

Table 2 Estimated Consolidation Water, Flow Rate and Average Flux during Deposition

Tailings Accumulative Consolidation Water

Average Flow Rate

Surface Area

Average Flux

(tonne) (m3) m3/year

m2 mm/day/m2

Year 1 10,500,000 933,578 933,578 205,966 12.4

Year 2 21,000,000 1,994,680 1,061,102 373,075 7.8

Year 3 31,500,000 3,244,492 1,249,813 446,472 7.7

Year 4 42,000,000 4,575,578 1,331,086 509,506 7.2

Year 5 52,500,000 5,538,522 962,945 573,851 4.6

Year 6 63,000,000 7,415,108 1,876,585 640,036 8.0

Year 7 73,500,000 8,894,673 1,479,565 676,049 6.0

Year 8 84,000,000 10,442,897 1,548,223 736,427 5.8

Year 9 94,500,000 11,987,700 1,544,804 768,886 5.5

Year 10 100,000,000 13,066,624 1,078,924 805,614 3.7

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Figure 4 Estimated Consolidation Water to be Released to the Pond

7.3 Consolidation after Deposition

After deposition, the tailings will continue to consolidate under self-weight and water in the tailings matrix

will be expelled and release to the tailings surface due to volume change and decrease in void ratio.

Consolidation settlement will also develop and result in a lowering tailings surface with time until

consolidation is completed. The degree of the consolidation is estimated based on the settlement.

Figure 5 shows the estimated maximum settlement at the centre of the pit (i.e. the deepest location)

versus time. It is estimated that the tailings will reach 35.0%, 43.0%, 90.0% and 98% consolidation after

1 year, 10 years, 100 years and 300 years respectively, during the post deposition periods. The

maximum consolidation settlement would be 54.0 m at the centre of the pit. However, the average

settlement could be less than 27.0 m due to the three dimensional effect. Figure 8 shows the dry density

profiles at Year 20, Year 100, Year 300 and at the end of consolidation. The final average dry density is

estimated to be 1.93 t/m3.

0

2,000,000

4,000,000

6,000,000

8,000,000

10,000,000

12,000,000

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0 2 4 6 8 10 12

Co

nso

lidat

ion

Wat

er

(m3

)

Time (year)

DuringDeposition

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Figure 5 Settlement vs. Time After Deposition

The estimated accumulative consolidation water after the deposition is shown in Figure 6. The volume of

the consolidation water is estimated to decrease from 220,900 m3 in the initial year (Year 11) to less than

4,000 m3 in Year 300. The estimated daily flow rate is shown in Figure 7.

Figure 6 Consolidation Water to Be Released to the Pond During Post Deposition Periods

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lem

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nso

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ion

Wat

er

(m3)

Time (year)

Post Deposition

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Figure 7 Flow Rate of Consolidation Water During Post Deposition Periods

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500

1000

1500

2000

0 20 40 60 80 100 120 140 160 180 200 220 240 260 280 300

Flo

w r

ate

(m

3/d

ay)

Time after Deposition (year)

Flow rate (m3/day)

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Figure 8 Estimated Dry Density Profiles During Post Deposition Periods

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De

pth

(m

)

Dry density (t/m3)

Year 20 Year 100 Year 300 Final

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8 Water Balance Estimates

In addition to the estimates of consolidation water volumes provided above in Section 7, we have also

estimated the overall volume of free water that could be generated by the tailings in-pit deposition

operation, and the volume of make-up water that could be required each year at the TSF to continue

slurrying of the tailings with water monitors as described in the draft Retreat Concept report (MRM,

2016).

The water balance estimates take into consideration the following elements:

Tailings density and moisture content characteristics as summarised in Table 3 below.

Bleed water recovered from the initial settlement of the tailings once deposited into the pit (i.e. the

differential water content between Stages 2 and 3 in Table 3 below).

Free water generated from consolidation of the tailings (i.e. consolidation water, as calculated in

Section 7 above).

Annual average evaporation from the surface area of the tailings (2,735 mm per annum).

Annual average rainfall over the plan area of the pit (805 mm per annum over an area of 2.55Mm2).

A run-off coefficient of 1 has been selected for rainfall, and a sensitivity analysis was conducted by

considering a range of annual rainfalls from the 10th percentile (i.e. dry) year to the 90th percentile

(i.e. wet year).

As advised by KCB (refer email dated 20th Sep 2016, titled “MRM In-Pit Tailings Consolidation Works -

notes from kick off meeting - groundwater inputs”), groundwater and potential inflows from McArthur

River, were not considered in this water balance estimate, on the basis that:

There will be no river flow entering the pit during tailings/waste rock placement.

Groundwater will continue to be managed through the dewatering system and will not enter the pit.

Table 3 Tailings Density at Various Stages During the In-Pit Deposition Operations

Property Stage 1

Tailings in TSF

Stage 2 Tailings Slurry Piped from TSF

to Pit

Stage 3 Tailings in Pit

Following Initial Settlement

Stage 4 Tailings in Pit After 10 Years

% solids by weight 82% 45% 66.1% 72.2%

% water by weight 18% 55% 33.9% 27.8%

% solids by volume 59% 21% 38.1% 45.2%

% voids by volume 41% 79% 61.9% 54.8%

Dry density [t/m3] 1.85 0.65 1.21 1.43

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Property Stage 1

Tailings in TSF

Stage 2 Tailings Slurry Piped from TSF

to Pit

Stage 3 Tailings in Pit

Following Initial Settlement

Stage 4 Tailings in Pit After 10 Years

Wet density [t/m3] 2.26 1.44 1.82 1.98

Specific gravity 3.16 3.16 3.16 3.16

Reference 2016 lab data

on tailings samples

MRM (2016) Retreat Concept

ATC Williams (2014) Outcomes of the study contained

herein.

Table 4 provides a summary of the water balance calculations undertaken and indicates that make up

water in the range of 0.62 to 2.11 Mm3 would be required at the TSF in order to slurry the tailings for the

case of average annual rainfall in each year.

Table 4 Summary of Water Balance Calculations

Year

Water required at

TSF to slurry

tailings [m3]

At the Pit

Make Up Water

Required at TSF (Mm3)

Bleed water from initial settlement

[m3]

Consolidation water [m3]

Evaporation from tailings beach area

[m3]

Average rainfall

inflow from pit

catchment

1 10,478,170 7,440,153 933,578 -563,317 2,049,216 0.62

2 10,478,170 7,440,153 1,061,102 -1,020,360 2,049,216 0.95

3 10,478,170 7,440,153 1,249,813 -1,221,101 2,049,216 0.96

4 10,478,170 7,440,153 1,331,086 -1,393,499 2,049,216 1.05

5 10,478,170 7,440,153 962,945 -1,569,482 2,049,216 1.60

6 10,478,170 7,440,153 1,876,585 -1,750,498 2,049,216 0.86

7 10,478,170 7,440,153 1,479,565 -1,848,994 2,049,216 1.36

8 10,478,170 7,440,153 1,548,223 -2,014,128 2,049,216 1.45

9 10,478,170 7,440,153 1,544,804 -2,102,903 2,049,216 1.55

10 10,478,170 7,440,153 1,078,924 -2,203,354 2,049,216 2.11

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In the case of 10th percentile rainfall occurring each year, an additional 0.9Mm3 of make-up water would

be required each year.

In the case of 90th percentile rainfall occurring each year we estimate that 0.98Mm3 less make-up water

would be required each year, such that there would be a surplus of water in Years 1, 2, 3 and 6.

9 Tailings Deposition Concept

The attached drawings SK001 to SK005 provide an indication of the filling of the pit over the 10 years.

Key aspects of the deposition concept include:

Tailings discharge pipe installed along the Western Ramp, and then down the western pit wall which

has a gradient of approximately 20°. Access to the discharge point would be required so that it could

be regularly adjusted – to allow for the increasing tailings beach elevation – and realigned

northwards / southwards to maximise the efficiency of the tailings deposition into the pit.

Tailings beach of a similar gradient (1V:150H) to that at the TSF has been estimated for this study.

A decant pond at the eastern side of the pit, to enable access to the pond via the main ramp for

installation and maintenance of pump(s) and associated infrastructure.

Construction of the 7.5 MT PAF waste rock cell in Year 2, based on its height being the same as the

depth of tailings deposited in Year 2. We have attempted to maximise the founding of the PAF

waste rockfill on rock (i.e. the IPD and the pit), however the drawings indicate that a portion of the

rockfill would be founded on tailings. The feasibility of this will require further analysis and

consideration because the tailings may not have sufficient strength to support such a rapid

development of the waste rockfill without careful design, planning and implementation.

10 Recommendations

It should be noted that consolidation of the tailings under self-weight will depend on the consolidation

characteristics of the tailings under different stress conditions encompassing a stress range from very

low effective stress after settling to very high effect stress at the bottom of the pit. The following

recommendations are provided for the further study of the project.

Column settling tests should be carried out at the target solids content.

Slurry consolidation tests should be carried out on the representative tailings samples to characterise

the consolidation properties of the tailings at different initial solids content.

It is recommended to carry out the slurry consolidation tests in connections of permeability tests at

different stress levels.

More detailed analyses should be undertaken with consolidation of three dimensional effect of the pit

geometries and the effect of the waste rock on the consolidation of the tailings.

The evaporative drying modelling of the tailings and drying tests should be carried out only to

investigate the effects of volume change during desiccation if a subaerial deposition is to be adopted

and the tailings are anticipated to be desiccated during dry seasons.

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Options for co-disposal of the 7.5MT PAF rockfill with the tailings in Year 2 should be further

considered. From a geotechnical perspective, it would be preferable to found the rockfill on rock. In

this regard, the possibility of spreading the rockfill disposal over a longer time period so that it could

have a greater height, and lesser footprint area could be considered. If the rockfill is to be founded

on tailings, further analysis and modelling should be undertaken to determine a suitable way for

undertaking this safely, in order to maintain stability of the placed rockfill and so as to maintain the

decant water quality.

11 References

GHD, 2016. MRM TSF – Stability Analysis for Life of Mine Preliminary Design, 8 March 2016.

Li, A.L., Been, K., Wislesky, I, Eldridge, T. and Williams, D. (2012). Tailings initial consolidation and

evaporative drying after deposition. The International Seminar on Paste and Thickened Tailings, Paste

2012, 16–19 April, 2012, Sun City, South Africa, pp.25-42.

ATC Williams, 2014 –McArthur River Mine Tailings Storage Facility Projected 5-Year Management Plan,

August 2014, document 111351.16.R01-b

MRM, 2016. MRM Tailings Retreatment Project Concept Study, 04 April 2016 Version 1 (Draft)

O’Kane Consultants, 2016, McArthur River Mine – Initial Consolidation Modelling for In-Pit Tailings; Fatal

Flaw Analysis for Pit Water Quality. 29 May 2016.

Kind Regards

GHD Pty Ltd

Allen LI & Matthew Daley

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Conditions of Use: This document may only be used by GHD's client (and any other

person who GHD has agreed can use this document) for the purpose for which it was

prepared and must not be used by any other person or for any other purpose.

rev description app'd date

SK

2 Salamanca Square Hobart TAS 7000 Australia

GPO Box 667 Hobart TAS 7001

T 61 3 6210 0600 F 61 3 6210 0601

E [email protected] W www.ghd.com

GHD STANDARD A3 SHEET CAD File No.: GHD_G_1022 Updated: 08-07-03 Version: 1.1

Plot Date: Cad File No:5 October 2016 - 1:15 PM G:\32\1747605\CADD\Drawings\32-1747605-SK001.dwgPlotted by: Stephanie Magaling

McARTHUR RIVER MINING

TAILINGS IN-PIT CONSOLIDATION

YEAR 1 TAILINGS BEACH

PLAN

001

A

32-1747605

PRELIMINARY

1:10000

OCT 2016

A INITIAL ISSUE

0 300m100 200

SCALE 1:10,000 AT ORIGINAL SIZE

N

MAIN RAMP

TAILINGS BEACH

DECANT POND

OREBODYFOOTWALL

POSSIBLE TAILINGSDISCHARGE PIPE ROUTE

WESTERN RAMP

IN PIT DUMP

IPD

10025

10025

10025 10025

10025

10025 10025 10025

10025

10025

10075

10075

10075

1007

5

10075

10050

10050

10050

10050 1005

0

10050

1005

0

10050

10050

10050

10050

10050

10050

1005

0

1005

0

10050

10050

10050

10050

1005

0

10050

10050

10050

10050

10050

1005

0

10050

1005

0

10050

10050

10050

10050 10050 10050

10050

10050

10025

10025

10025

10025

10025

10025 10025

10025

10025

10025

1002

5

10025 1002

5

1002

5

10025

1002

5

10025

10025

1002

5

1002

5 10025

10025

10025

1002

5 10025

10025

1002

5 10

025

10025 10025 10025

10025 10025

10025

10025

10025

10025

10025 10025

1002

5 10025

10025 10025 10025 10025

1002

5 10

025

1002

5 10

025

10025

10025

10025

10025

10025

10025

10025

10025

1002

5

1002

5

1002

5

1002

5

1002

5

1002

5

10025

10025 10025

10025

10000 10000

10000

1000

0 10

000

10000

10000 10000

10000

10000 10000

1000

0

10000

10000

10000 10000

1000

0 10000

10000

10000 10000

10000

1000

0

10000

1000

0 10

000

10000 10000

10000

10000

10000

1000

0

10000

1000

0

1000

0

10000

10000 10000

10000 1000

0

10000

10000

10000 10

000

10000

10000

1000

0 10000

1000

0

10000

1000

0 1000

0

10000 10000 10000

10000

10000

9975 9975

9975

9975

9975

9975

9975 99

75

9975 9975

9975

9975

9975

9975

9975

9975

9975

9975 9975

9950

9950

9950 9950

9950

9950

9950

9950

9950

9950

9950

9950

9950

9950

9950 99

50

9950

9925

9925

9925

9925

9925

9925

9925

9925 99

25 99

25

9925

9925 9925

9925

9925

9900

9900

9900

9900

9900

9900

9900

9900

9900

9900

9900

9900

9900

9900

9900

9875 98

75 98

75 9875

ASK005

ASK005

9750

.6

9753

.6

9751

.6

9752

.6

date

for A3

rev no.

job no.scale

approved (PD)





SK



T 61 3 6210 0600 F 61 3 6210 0601







PLAN

002

A

32-1747605

PRELIMINARY

1:10000

OCT 2016

A INITIAL ISSUE

0 300m100 200


N

MAIN RAMP

TAILINGS BEACH

DECANT POND

OREBODYFOOTWALL


WESTERN RAMP

IN PIT DUMP

IPD

LEGEND:

PAF CELL ABOVE YR1 DRY TAILINGS BEACH

PAF CELL

10025

10025

10025 10025

10025

10025 10025 10025

10025

10025

10075

10075

10075

1007

5

10075

10050

10050

10050

10050 1005

0

10050

1005

0

10050

10050

10050

10050

10050

10050

1005

0

1005

0

10050

10050

10050

10050

1005

0

10050

10050

10050

10050

10050

1005

0

10050

1005

0

10050

10050

10050

10050 10050 10050

10050

10050

10025

10025

10025

10025

10025

10025 10025

10025

10025

10025

1002

5

10025 1002

5

1002

5

10025

1002

5

10025

10025

1002

5

1002

5 10025

10025

10025

1002

5 10025

10025

1002

5 10

025

10025 10025 10025

10025 10025

10025

10025

10025

10025

10025 10025

1002

5 10025

10025 10025 10025 10025

1002

5 10

025

1002

5 10

025

10025

10025

10025

10025

10025

10025

10025

10025

1002

5

1002

5

1002

5

1002

5

1002

5

1002

5

10025

10025 10025

10025

10000 10000

10000

1000

0 10

000

10000

10000 10000

10000

10000 10000

1000

0

10000

10000

10000 10000

1000

0 10000

10000

10000 10000

10000

1000

0

10000

1000

0 10

000

10000 10000

10000

10000

10000

1000

0

10000

1000

0

1000

0

10000

10000 10000

10000 1000

0

10000

10000

10000 10

000

10000

10000

1000

0 10000

1000

0

10000

1000

0 1000

0

10000 10000 10000

10000

10000

9975 9975

9975

9975

9975

9975

9975 99

75

9975 9975

9975

9975

9975

9975

9975

9975

9975

9975 9975

9950

9950

9950 9950

9950

9950

9950

9950

9950

9950

9950

9950

9950

9950

9950 99

50

9950

9925

9925

9925

9925

9925

9925

9925

9925 99

25 99

25

9925

9925 9925

9925

9925

9900

9900

9900

9900

9900

9900

9900

9900

9900

9900

9900

9900

9900

9900

9900

9875 98

75 98

75 9875

ASK005

ASK005

9798

.39799

.3

9797

.3

9796

.3

9800

.3

date

for A3

rev no.

job no.scale

approved (PD)





SK



T 61 3 6210 0600 F 61 3 6210 0601







PLAN

003

A

32-1747605

PRELIMINARY

1:10000

OCT 2016

A INITIAL ISSUE

0 300m100 200


N

MAIN RAMP

OREBODYFOOTWALL

TAILINGS BEACH


WESTERN RAMP

IN PIT DUMP

IPD

DECANT POND

10025

10025

10025 10025

10025

10025 10025 10025

10025

10025

10075

10075

10075

1007

5

10075

10050

10050

10050

10050 1005

0

10050

1005

0

10050

10050

10050

10050

10050

10050

1005

0

1005

0

10050

10050

10050

10050

1005

0

10050

10050

10050

10050

10050

1005

0

10050

1005

0

10050

10050

10050

10050 10050 10050

10050

10050

10025

10025

10025

10025

10025

10025 10025

10025

10025

10025

1002

5

10025 1002

5

1002

5

10025

1002

5

10025

10025

1002

5

1002

5 10025

10025

10025

1002

5 10025

10025

1002

5 10

025

10025 10025 10025

10025 10025

10025

10025

10025

10025

10025 10025

1002

5 10025

10025 10025 10025 10025

1002

5 10

025

1002

5 10

025

10025

10025

10025

10025

10025

10025

10025

10025

1002

5

1002

5

1002

5

1002

5

1002

5

1002

5

10025

10025 10025

10025

10000 10000

10000

1000

0 10

000

10000

10000 10000

10000

10000 10000

1000

0

10000

10000

10000 10000

1000

0 10000

10000

10000 10000

10000

1000

0

10000

1000

0 10

000

10000 10000

10000

10000

10000

1000

0

10000

1000

0

1000

0

10000

10000 10000

10000 1000

0

10000

10000

10000 10

000

10000

10000

1000

0 10000

1000

0

10000

1000

0 1000

0

10000 10000 10000

10000

10000

9975 9975

9975

9975

9975

9975

9975 99

75

9975 9975

9975

9975

9975

9975

9975

9975

9975

9975 9975

9950

9950

9950 9950

9950

9950

9950

9950

9950

9950

9950

9950

9950

9950

9950 99

50

9950

9925

9925

9925

9925

9925

9925

9925

9925 99

25 99

25

9925

9925 9925

9925

9925

9900

9900

9900

9900

9900

9900

9900

9900

9900

9900

9900

9900

9900

9900

9900

9875 98

75 98

75 9875

ASK005

ASK005

9847

.5

9848

.5

9849

.5

9846

.5

9845

.5

9844

.59850

.5

date

for A3

rev no.

job no.scale

approved (PD)





SK



T 61 3 6210 0600 F 61 3 6210 0601







PLAN

004

A

32-1747605

PRELIMINARY

1:10000

OCT 2016

A INITIAL ISSUE

0 300m100 200


N

MAIN RAMP

TAILINGS BEACH

DECANT POND

OREBODYFOOTWALL


WESTERN RAMP

IN PIT DUMP

IPD

PAF ROCK

IPD SURFACE

PIT SURFACE

FALL 1:150 APPROXIMATE

FALL 1:150 APPROXIMATE

DECANTPOND

RL 9888

YR2 TAILINGS BEACH - RL 9754.5




YR6 TAILINGS BEACH - RL 9813.0YR7 TAILINGS BEACH - RL 9824.0

YR8 TAILINGS BEACH - RL 9834.0YR9 TAILINGS BEACH - RL 9843.0



RL 9616

TAILINGS DISCHARGE PIPE

date

for A3

rev no.

job no.scale

approved (PD)





SK



T 61 3 6210 0600 F 61 3 6210 0601






CROSS SECTION

005

A

32-1747605

PRELIMINARY

1:2500

OCT 2016

A INITIAL ISSUE

0 75m25 50

SCALE 1:2500 AT ORIGINAL SIZE

SECTIONASK001-SK004 SCALE 1:2500

NOTE:1. SECTION IS FOCUSED ON LOWER PORTION OF PIT AND

DOES NOT SHOW FULL EXTENT.

Tailings Deposition into Open Pit Consolidation Modelling · 2017-03-21 · Tailings Deposition...

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