bajool marble quarry - environment · consist of haul roads, three waste rock emplacement areas, a...

Bajool Marble Quarry Water Management Plan

Omya Australia Pty Ltd

0802-02-C2, 5 January 2018

For and on behalf of WRM Water & Environment Pty Ltd Level 9, 135 Wickham Tce, Spring Hill PO Box 10703 Brisbane Adelaide St Qld 4000 Tel 07 3225 0200

David Newton Director

NOTE: This report has been prepared on the assumption that all information, data and reports provided to us by our client, on behalf of our client, or by third parties (e.g. government agencies) is complete and accurate and on the basis that such other assumptions we have identified (whether or not those assumptions have been identified in this advice) are correct. You must inform us if any of the assumptions are not complete or accurate. We retain ownership of all copyright in this report. Except where you obtain our prior written consent, this report may only be used by our client for the purpose for which it has been provided by us.

wrmwater.com.au 0802-02-C2| 5 January 2018 |

Contents

1 Introduction ___________________________________________________ 5

1.1 Overview ________________________________________________________ 5

1.2 Purpose and scope ________________________________________________ 5

1.3 Project description _______________________________________________ 5

1.4 Plan of operation _________________________________________________ 6

2 Existing Environment ____________________________________________ 9

2.1 Overview ________________________________________________________ 9

2.2 Receiving water environmental values _______________________________ 9

2.3 Drainage characteristics __________________________________________ 11

2.3.1 Regional drainage__________________________________________ 11

2.3.2 Local drainage ____________________________________________ 11

2.4 Release limits ___________________________________________________ 13

2.5 Water quality ___________________________________________________ 14

3 Surface water management system ________________________________ 18

3.1 Water types ____________________________________________________ 18

3.1.1 External or raw water ______________________________________ 18

3.1.2 Diverted water ____________________________________________ 18

3.1.3 Surface water _____________________________________________ 18

3.1.4 Worked water _____________________________________________ 18

3.1.5 Associated water __________________________________________ 18

3.2 Water management objectives ____________________________________ 18

3.3 Water management infrastructure _________________________________ 19

3.4 Contaminant sources _____________________________________________ 20

3.4.1 Saline drainage and acid rock drainage _______________________ 21

3.5 Erosion and sediment control _____________________________________ 21

3.5.1 Overview _________________________________________________ 21

3.5.2 Objectives and principles ___________________________________ 21

3.5.3 Drainage control measures __________________________________ 22

3.5.4 Erosion control measures ___________________________________ 23

3.5.5 Sediment control measures _________________________________ 24

4 Groundwater aquifers __________________________________________ 25

4.1 Overview _______________________________________________________ 25

4.2 Geological setting _______________________________________________ 25

4.3 Regional groundwater aquifers ____________________________________ 25

4.4 Impact of mining on groundwater __________________________________ 26

4.5 Associated water monitoring ______________________________________ 26

5 Mine site water balance _________________________________________ 28

http://wrmwater.com.au/


5.1 Overview _______________________________________________________ 28

5.2 Available data __________________________________________________ 28

5.2.1 Rainfall __________________________________________________ 28

5.2.2 Evaporation _______________________________________________ 29

5.3 Water balance model ____________________________________________ 30

5.3.1 Simulation methodology ____________________________________ 30

5.3.2 Catchment area ___________________________________________ 30

5.3.3 Catchment runoff __________________________________________ 33

5.3.4 Site water demands ________________________________________ 33

5.3.5 Water storages ____________________________________________ 33

5.3.6 Model results______________________________________________ 34

6 Water Monitoring Plan __________________________________________ 37

6.1 Surface water quality ____________________________________________ 37

6.2 Surface water quantity ___________________________________________ 37

6.3 Groundwater quality _____________________________________________ 37

6.3.1 Groundwater Monitoring ____________________________________ 37

7 Emergency and Contingency Plan _________________________________ 39

7.1 Overview _______________________________________________________ 39

7.2 Water releases __________________________________________________ 39

7.3 Post-event monitoring____________________________________________ 39

8 Responsibilities and Review ______________________________________ 40

9 References ___________________________________________________ 41



List of Figures

Figure 1.1 – Regional drainage network and locality _________________________________ 7

Figure 1.2 –Bajool Marble Mine Tenements _________________________________________ 8

Figure 2.1 – Local drainage network ______________________________________________ 12

Figure 2.2 – Photograph of sediment dam showing trapped sediment and permeable dam wall ___________________________________________________________ 13

Figure 2.3 – Water monitoring locations ___________________________________________ 14

Figure 2.4 – Water quality results, electrical conductivity ___________________________ 15

Figure 2.5 – Water quality results, pH ____________________________________________ 16

Figure 2.6 – Water quality results, total suspended solids ____________________________ 16

Figure 3.1 – Water management system schematic _________________________________ 20

Figure 3.2 – Photograph showing low turbidity of water in active quarry pit ____________ 21

Figure 4.1 – Location of bores within 3 km of Bajool Marble Mine _____________________ 26

Figure 5.1 – Mean monthly rainfall and lake evaporation at BMM, Jan 1889 to Jun 2017 ___________________________________________________________ 29

Figure 5.2 – Catchment and landuse boundary _____________________________________ 32

Figure 5.3 – Quarry yearly overflow volume________________________________________ 35

Figure 5.4 – North Quarry daily volume under different climatic conditions ____________ 36

Figure 5.5 – Wells Quarry daily total volume under different climatic conditions ________ 36

List of Tables

Table 2.1 – Water quality objectives, Raglan Creek and tributaries in the Fitzroy River sub-basin ........................................................................... 10

Table 2.2 – Monitoring locations and mine water affected water release limits ............. 13

Table 2.3 – Statistical analysis of water quality results .......................................... 17

Table 3.1 – Contaminant sources and destination of runoff ..................................... 20

Table 3.2 – Allowable flow velocities for open earth lined drains .............................. 22

Table 3.3 – Summary of erosion control techniques .............................................. 23

Table 3.4 – Summary of supplementary sediment control techniques ......................... 24

Table 4.1 – Details of regional registered bores within 3 km of the mine ..................... 25

Table 5.1 – Mean monthly rainfall and evaporation ............................................... 29

Table 5.2 – Adopted catchment area ................................................................ 31

Table 5.3 – AWBM parameters for various catchment types ..................................... 33

Table 5.4 – Storage catchment areas and volumes ................................................ 34



1 Introduction

1.1 OVERVIEW This document presents a Water Management Plan (WMP) for the Bajool Marble Mine (BMM) operations, including the proposed expansion of the Wells Rock Emplacement Area (WREA). The document has been developed consistent with the Department of Environment and Heritage Protection (DEHP) guideline “Preparation of Water Management Plans for Mining Activities – EM324” (DEHP, 2012).

1.2 PURPOSE AND SCOPE This WMP has been prepared in response to an information request from DEHP. The WMP aims to:

x Provide for effective management of actual and potential environmental impacts resulting from water management associated with the mining activity carried out under this environmental authority; and

x Be developed in accordance with the Department of Environment and Heritage Protection (DEHP) Guidelines on the Preparation of Water Management Plans for Mining Activities (DEHP, 2013a) including:

o A study of the source of contaminants;

o A water balance model for the site;

o A water management system for the site;

o Measures to manage and prevent saline drainage;

o Measures to manage and prevent acid rock drainage;

o Contingency procedures for emergencies; and

o A program for monitoring and review of the effectiveness of the Water Management Plan.

The WMP examines and addresses all issues relevant to the importation, generation, use, and management of water on a mining project in order to minimise the quantity of water that is contaminated. During the care and maintenance phase, water will not be needed for operational use. The key goals of the water management system (WMS) will be:

x Maintain compliance with the BMM’s EA;

x Minimise the generation of water on site, while maximizing the volume of water that runs off site, consistent with the site Plan of Operations and Environmental Management Plan; and

x Minimise the use of site resources for pumping.

The potential risks of environmental harm to natural waterways posed by mining activities have been identified and management actions that will effectively minimise these risks have been presented.

1.3 PROJECT DESCRIPTION The mine is located approximately 17 km south of Bajool, Queensland. Figure 1.1 shows the location of BMM and Figure 1.2 shows the various tenements. BMM is owned and operated by Omya Australia Pty Ltd. The mine leases cover 232.94 ha. In 2015, BMM produced 226,000 tonnes of crusher feed and 58,000 tonnes of pit waste from the crusher feed. The mining and processing rates will not be influenced by the expansion of the



WREA. BMM has forecast approximately 300,000 tpa of product rock to be mined each year.

The main mining area at BMM site is the active Wells Quarry. North Quarry, located to the north of Wells Quarry, is an inactive mining area. The key components of the operation consist of haul roads, three waste rock emplacement areas, a crushing plant, a small stone dust mill, bagging plant, maintenance workshop and associated infrastructure.

1.4 PLAN OF OPERATION The BMM has been in operation since 1980, producing white high purity crushed marble. Due to the large size of the deposit and the small annual rate of production, the mine life is considered to be indefinite (Omya, 2016).

A detailed description of the operation is provided in the Omya Plan of Operation 2014-2019 document (Omya, n.d.). The document was prepared to address the conditions stated in the Non-standard Environmental Authority (Mining Activities) Permit No. EPML00657813 and in accordance to Section 288 of the Queensland Environmental Protection Act 1994.



Figure 1.1 – Regional drainage network and locality



Figure 1.2 –Bajool Marble Mine Tenements

North Quarry

Wells Quarry



2 Existing Environment

2.1 OVERVIEW This section of the WMP describes the environmental values and the regional drainage characteristics in the vicinity of BMM. The environmental values as defined by the Environmental Protection Act 1994, Environmental Protection (Water) Policy 2009 and the Australian and New Zealand Guidelines for Fresh and Marine Water Quality (ANZECC/ARMCANZ 2000) and regulations of these waterways are described.

2.2 RECEIVING WATER ENVIRONMENTAL VALUES The Environmental Protection Act 1994 aims to protect Queensland’s water, whilst allowing ecologically sustainable development through the Environmental Protection (Water) Policy 2009 (EPP Water). The EPP Water achieves this within the following framework:

x Identifying environmental values (EVs) for aquatic ecosystems and for human use; and

x Determine Water Quality Guidelines (WQGs) and Water Quality Objectives (WQOs) to enhance or protect the EVs.

Environmental values are the qualities of waterways to be protected from activities in the catchment. Protecting environmental values aims to ensure healthy aquatic ecosystems and waterways that are safe and suitable for community use. Environmental values reflect the ecological, social and economic values and uses of the waterway, (such as stock water, swimming, fishing and agriculture).

The processes to identify EVs and determine WQGs and WQOs are based on the National Water Quality Management Strategy (ANZECC/ARMCANZ, 1994), Implementation Guidelines (1998) and further outlined in the Australian and New Zealand Guidelines for Fresh and Marine Water Quality (ANZECC/ARMCANZ 2000). EVs and WQOs adopted for particular Queensland waters are included in Schedule 1 of the EPP Water.

BMM is located within the Fitzroy River Sub-basin in the Raglan Creek and tributaries section (DEHP, 2013). The identified environmental values for the BMM site are:

x Aquatic ecosystems;

x Irrigation;

x Farm supply/use;

x Stock water;

x Human consumer;

x Primary recreation;

x Secondary recreation;

x Visual recreation;

x Drinking water;

x Industrial use; and

x Cultural and spiritual values.

Table 2.1 shows the water quality objectives for the Raglan Creek and tributaries given in the Fitzroy River Sub-basin (DEHP, 2013) and the Australian and New Zealand Guidelines for Fresh and Marine Water Quality (ANZECC, 2000). The Raglan Creek and tributaries are Ephemeral with short flow durations after rain.



Table 2.1 – Water quality objectives, Raglan Creek and tributaries in the Fitzroy River sub-basin

Parameters A

quat

ic

Ecos

yste

ms

Irri

gati

on

Stoc

k W

ater

Aqu

acul

ture

(F

resh

Wat

er)

Prim

ary

Recr

eati

on

Seco

ndar

y Re

crea

tion

Indu

stri

al U

se

pH 6.5-8.5 6.8-9.5 6.5-8.5

Salinity

<445 𝜇S/cm baseflow

<250 𝜇S/cm high flow

0-5 ppt <450 𝜇S/cm

Turbidity (NTU) <50 <80

Total Phosphorus <50 𝜇g/L

Total Nitrogen <500 𝜇g/L

Dissolved Oxygen (%) 85-110 >4 >80

Total Dissolved Solids (mg/L)

4000 for beef cattle 5000 for sheep 2000 for poultry

1,000,000 𝜇g/L

Temperature (0C) 21-32 16-34

Suspended Solids (mg/L) <85

Sulphate (mg/L) <15 400,000 𝜇g/L

Nitrate (NO3) (mg/L) 1-100 10,000 𝜇g/L

Nitrate (NO2) (mg/L) <0.1 1000 𝜇g/L

Aluminium (mg/L) 5 5 200 𝜇g/L

Arsenic (mg/L) 0.1 0.5 <0.05 50 𝜇g/L

Cadmium (mg/L) 0.01 0.01 <0.003 5 𝜇g/L

Calcium/Magnesium (mg/L)

10-160

Chromium (mg/L) 0.1 1 <0.1 50 𝜇g/L

Copper (mg/L) 0.2

0.4 for sheep 1 for cattle 5 for pigs

5 for poultry

<0.006 in soft water

1000 𝜇g/L

Cyanide (mg/L) <0.005 100 𝜇g/L

Iron (mg/L) 0.2 - <0.5 300 𝜇g/L

Lead (mg/L) 2 0.1 <0.03 50 𝜇g/L

Manganese (mg/L) 0.2 - <0.01 100 𝜇g/L

Mercury (mg/L) 0.002 0.002 <0.00005 1 𝜇g/L

Nickel (mg/L) 0.2 1 <0.01 in soft water <0.04 in hard water 100 𝜇g/L

Tin (mg/L) <0.001 mg/L

Zinc (mg/L) 2 20 0.03-0.06 in soft

water 1-2 in hard water

1000 𝜇g/L

Note: No numerical values provided for Farm Supply, Human Consumption, Visual Appreciation or Cultural & Spiritual Values



2.3 DRAINAGE CHARACTERISTICS

2.3.1 Regional drainage BMM is located on the western side of Mt McCamley within the catchment of Eight Mile Creek, a tributary of Raglan Creek. The regional drainage in the vicinity of the project is shown in Figure 1.1.

2.3.2 Local drainage The local drainage features are shown in Figure 2.1, Eight Mile Creek is the receiving waters for BMM. Undisturbed upslope catchments are directed through existing drainage lines or drains which are constructed and maintained in accordance with the BMM ESCP and the IECA (2008) guidelines for upslope diversion drains.

Disturbed areas of the site drain to sediment dams for sediment settlement prior to discharge from the site in accordance with the BMM ESCP. Sediment dams are a Type A sediment basin (IECA 2008) which allow “low flow” free drainage through a rock embankment. The rock embankments are constructed using waste rock material and are densely vegetated to provide scour and erosion protection. Sediment basin outflows occur by slow seepage through the permeable dam walls, as shown in Figure 2.2.

There are levees and drains surrounding the Wells Quarry and haul roads that direct runoff from disturbed areas away from the active pit. A levee on the northern boundary of Wells Quarry directs runoff away from the active pit to a tributary of Langmorn Creek. Disturbed area runoff is collected within the mine water system.



Figure 2.1 – Local drainage network

Clean water diversion levee



Figure 2.2 – Photograph of sediment dam showing trapped sediment and permeable dam wall

2.4 RELEASE LIMITS The contaminant release limits specified in the EA (EMPL00657813, DEHP 2014) are shown in Table 2.2. Figure 2.3 shows the surface water monitoring locations.

Table 2.2 – Monitoring locations and mine water affected water release limits

* WAT3b (BQW 2) is the alternate monitoring locations until July 2017 as access to BQW 2 was not able to be safely achieved. All monitoring locations will be undertaken at BQW2 as per the EA conditions from August 2017.

Location pH (pH units)

Electrical conductivity

(µS/cm)

Total Suspended Solids (mg/L)

Receiving water monitoring locations

BQW 1 (upstream of receiving

water) - - -

BQW 2* (downstream of receiving water)

- If BQW1>250 µS/cm then BQW2 not more

than 10%>BQW1

If BQW1<250 mg/L then BQW2=250 mg/L

If BQW1>250 mg/L

then BQW2 not more than 10%>250 mg/L

Release point monitoring locations

BQW 3 (stormwater) 6.5 - 8.5 250 500

BQW 4 (pit water) 6.5 - 8.5 1000 50



Figure 2.3 – Water monitoring locations

2.5 WATER QUALITY The latest water quality results include samples from November 2016 to April 2017. Figure 2.4, Figure 2.5 and Figure 2.6 show graphs of laboratory results and EA limits for electrical conductivity, pH and suspended solids respectively. Table 2.3 shows the statistical analysis of the water quality results at BMM. The period of record for the water quality data is from February 2010 to June 2011 and November 2016 to April 2017.

The number of samples during 2016 and 2017 is less than the minimum required to derive local water quality values (at least 18 samples in 12-24 months) for sites excluding BQW 4 (pit water) (ANZECC, 2000).

Based on the sampling results for BQW 4 (pit water), the following is of note:

x EC values are below the release limit of 1,000 μs/cm, therefore the risk of exceedance is low;

x pH values are within the release limits of 6.5 to 8.5, therefore the risk of exceedance is low; and

x TSS values are below the release limit of 50 mg/L, therefore the risk of exceedance is low;

Based on the sampling results for BQW 3 (stormwater), the following is of note:

x median EC value of 489 μs/cm is above the release limit of 250 μs/cm, therefore there is a risk of exceedance;

x pH values are within the release limits of 6.5 to 8.5, therefore the risk of exceedance is low; and



x three TSS results are reported, one of which exceeded the TSS limit of 500 mg/L, therefore there is a risk of exceedance;

Based on the sampling results at BQW 1 and BQW 2 (upstream and downstream receiving waters) the following is of note:

x the maximum EC recorded is above the release limit of 1,000 μs/cm, which indicates that the receiving waters can have higher background EC values than the release limits;

x the maximum pH recorded is above the release limit of 8.5, which indicates that the receiving waters can have higher background pH values than the release limits; and

x the maximum pH recorded is above the release limit of 50 mg/L for pit water, which indicates that the receiving waters can have higher background TSS values than the release limits.

The recorded water quality data indicates that there is some risk of exceedances to EA conditions from the release of stormwater. However, elevated levels of EC, pH and TSS in the receiving waters indicate that background water quality may exceed the release limits, therefore the risk of environmental harm from releases of water from BMM is low.

Water quality monitoring for additional parameters such as metals and hydrocarbons commenced in the 2016/2017 wet season. Two events were sampled in the 2016/2017 wet season. There were no exceedances for metals in Wells Pit or the receiving waters compared to TABLE F3 of the BMM EA. Based on the ANZECC (2000) guidelines, at least 18 samples are required over a 12 to 24 month period to derive local trigger levels for metals. Additional sampling will be required before site specific local trigger levels can be derived.

Figure 2.4 – Water quality results, electrical conductivity

0

200

400

600

800

1000

1200

1/11

/201

6

1/12

/201

6

1/01

/201

7

1/02

/201

7

1/03

/201

7

1/04

/201

7

1/05

/201

7

1/06

/201

7

Elec

tric

al

Con

duct

ivit

y (µ

S/cm

)

Electrical Conductivity

BQW3 Upper Limit BQW4 Upper Limit BQW1 BQW2 BQW3 BQW4



Figure 2.5 – Water quality results, pH

*Note: Single value of 2620 mg/L recorded at BQW3 on 16/01/2017

Figure 2.6 – Water quality results, total suspended solids

6

6.5

7

7.5

8

8.5

91/

11/2

016

1/12

/201

6

1/01

/201

7

1/02

/201

7

1/03

/201

7

1/04

/201

7

1/05

/201

7

1/06

/201

7

pH (

pH u

nit)

pH

BQW3&4 Lower Limit BQW3&4 Upper Limit BQW1 BQW2 BQW3 BQW4

0

50

100

150

200

250

300

350

400

450

500

550

600

1/11

/201

6

1/12

/201

6

1/01

/201

7

1/02

/201

7

1/03

/201

7

1/04

/201

7

1/05

/201

7

1/06

/201

7

Susp

ende

d So

lids

(mg/

L)

Suspended Solids

BQW3 Upper Limit BQW4 Upper Limit BQW1 BQW2 BQW3 BQW4



Table 2.3 – Statistical analysis of water quality results

Location Parameter pH EC (µS/cm)

Turbidity (NTU) TSS (mg/L)

BQW 1 (Upstream)

Minimum 7.5 222 3.6 5

Median 7.8 323 30 7

Maximum 8.6 1060 228 173

No. of samples 7 7 5 4

BQW 2 (Downstream)

Minimum 7.4 120 1.4 5.0

Median 7.7 400 19.6 7.5

Maximum 8.6 1030 58 49


BQW 3 (Stormwater)

Minimum 7.6 139 10 138

Median 7.7 489 12 216

Maximum 8.2 591 4140 2620


BQW 4 (Pit Water)

Minimum 7.9 306 10 5.0

Median 8.0 412 10 5.0

Maximum 8.4 537 10 31




3 Surface water management system

3.1 WATER TYPES For water management system purposes, the water generated at BMM is divided into five types.

3.1.1 External or raw water

External or raw water is water brought onto site of potable quality, this is often from an external source (i.e. trucked in drinking water).

3.1.2 Diverted water

Diverted water is runoff from areas surrounding the mine that is undisturbed and diverted away from the operations with no impact from the mine site. Diverted water is directed to the receiving waters.

The effective operation of drainage structures diverting water away from disturbed area runoff water storages is critical to the effective management of disturbed area runoff in the site water containment systems. Diverted water is managed under the BMM ESCP.

3.1.3 Surface water

Surface water (Stormwater) is runoff from areas on the mine lease that have been disturbed but not in an active operational area, or have been rehabilitated. The only potential contaminant is suspended solids, and this can be controlled through the BMM ESCP. Surface water catchments should drain off the lease via control structures and not accumulate in dams. Any surface water that does accumulate in a dam shall only be discharged in compliance with BMM’s EA conditions.

3.1.4 Worked water

Worked water (pit water) is water that has come into contact with operational areas such as active mine areas, pits, the workshop or runoff from stockpiles. This water shall be stored in designated dams or pits. Discharge of this water must be in compliance with BMM’s EA conditions.

BMM shall maximise the reuse of worked water for all operational purposes that don’t require potable water.

3.1.5 Associated water

Associated water is water that drains into pits from groundwater sources. There is no dewatering of groundwater from bores at BMM. Associated water is managed as worked water on site.

3.2 WATER MANAGEMENT OBJECTIVES The objectives of water management on-site are based on the two types of water generated on site, worked water and surface water.

The worked water management hierarchy is to:

x Minimise worked water catchment area to reduce the potential contamination of water and the accumulation of water on site;

x Dewater worked water storages at risk of uncontrolled discharge; and

x Remove excess worked water from site via controlled releases as per BMM’s EA.



The surface water management on site is in accordance with the BMM ESCP, the hierarchy is to:

x Prevent and minimise disturbance and progressively rehabilitate disturbed land to reduce the catchment area of surface water catchments:

x Rehabilitated land will be allowed to drain off site so long as it does not cause any erosion, through installation of erosion protection as per the ESCP; and

x Any surface water catchments with disturbance that will only generate sediment as a contaminant, will be directed through and ESCP sediment control structure, such as a sediment basin to remove sediment loading to be compliant with release conditions in the BMM EA.

3.3 WATER MANAGEMENT INFRASTRUCTURE A schematised plan for the water management system configuration is shown in Figure 3.1. Figure 5.2 shows the locations of each storage at BMM. The surface water management system includes the following key features:

x North Quarry supplies water for dust suppression and the crusher plant.

x Process water from the crusher plant is stored in the Process Water Dam before being recycled through the crusher plant.

x Wells Quarry is continually dewatered to North Quarry. If North Quarry is full, water from Wells Quarry is dewatered to Sediment Dam 12 prior to release from site via BQW4.

x Sediment dams 1 to 8 collect surface water runoff from the North Quarry area.

x Sediment dams 12 and 13 collect surface water runoff from the Wells Quarry and associated waste rock emplacement.



Figure 3.1 – Water management system schematic

3.4 CONTAMINANT SOURCES The primary potential contaminants generated by the project is sediment. Dispersive soils have not been encountered at BMM and sediment readily settles within the quarry pit and sediment dams. Figure 3.2 is a photograph showing low turbidity water within the active quarry pit.

The key potential sources of contaminants are shown in Table 3.1, along with the destination storages that water from each source reports to.

Table 3.1 – Contaminant sources and destination of runoff

Contaminant source Destination water storage North Quarry Sediment dam

Wells Quarry Pumps to North Quarry or sediment dam

Groundwater inflows North Quarry and Wells Quarry

Haul road Sediment dams

Waste rock dumps Sediment dams

Crusher plant Process Water Dam and Sediment dams



3.4.1 Saline drainage and acid rock drainage

Water quality data in Section 2.5 and previous onsite investigations indicates that saline drainage and acid rock drainage are not present at BMM. Water quality in the pits and the sediment dams is generally neutral with EC below 1,000 μs/cm. Water quality monitoring as outlined in Section 6 will identify if any saline drainage or acid rock drainage occurs at site.

Figure 3.2 – Photograph showing low turbidity of water in active quarry pit

3.5 EROSION AND SEDIMENT CONTROL

3.5.1 Overview

Erosion and sediment control infrastructure across the site are documented in the Omya Environmental Management Plan which has been developed based on the principles outlined below.

3.5.2 Objectives and principles

Preventing exceedances of EA conditions for total suspended solids (sediment) from leaving the site and entering the receiving waters is outlined in detail in the BMM Erosion and Sediment Control Plan (ESC). As per IECA (2008), ESC activities on the site should be managed to achieve the following key objectives:

x Drainage control – prevention or reduction of soil erosion by concentrated flows and appropriate management and separation of the movement of clean and dirty water through the area of concern.

x Erosion control – prevention or minimisation of soil erosion (from dispersive, non-dispersive or competent material) caused by rain drop impact and exacerbated overland flow on disturbed surfaces.

x Sediment control – trapping or retention of sediment either moving along the land surface, contained within runoff (e.g. from up-slope erosion) or from windborne particles.

For ESC to be effective, the following fundamentals are required (IECA, 2008):

x ensure ESC measures are designed and constructed effectively;

x minimise the duration and extent of soil exposure;

x promptly stabilise disturbed areas;

x maximise sediment retention on the site;

x control water movement through the site;



x minimise soil erosion wherever possible rather than applying down slope sediment controls;

x utilise existing topography and adopt construction practices that minimise soil erosion and sediment discharge from area;

x integrate erosion and sediment control issues / measures into the planning phases of mine operations;

x choose the ESC technique to account for site conditions such as soil, weather and construction conditions;

x maintain all ESC measures in proper working order at all times; and

x monitor the site and adjust ESC practices to maintain the required performance standard.

3.5.3 Drainage control measures

Drainage channels, whether permanent or temporary, should be designed and constructed at a gradient that limits the maximum flow velocity for the adopted design event standard to a value not exceeding the maximum allowable flow velocity for the given surface material.

Excessive flow velocities can cause channel erosion, usually along the invert of the drain, which can then lead to bank slumping and widening of the channel. Table 3.2 lists allowable flow velocities for earth lines drains as per IECA (2008).

Table 3.2 – Allowable flow velocities for open earth lined drains

Soil description Allowable velocity (m/s)

Comments

Extremely erodible soils

0.3 x Dispersive clays are highly erodible even at low flow velocities and therefore must either be treated (e.g. with gypsum) or covered with a minimum of 100mm of stable soil.

x Highly erodible soils may include: Lithosols, Alluvials, Podzols, Siliceous sands, Soloths, Solodized solonetz, Grey podzolics, some Black earths, fine surface texture-contract soils and Soil Groups ML and CL.

x Moderately erodible may include: Red earths, Red or Yellow podzolics, some Black earths, Grey or Brown clays, Prarie soils and Soil Groups SW, SP, SM, SC.

x Erosion-resistant soils may include: Xanthozem, Euchrozem, Krasnozems, some Red earth soils and Soil Groups GW, GP, GM, GC, MH and CH.

Sandy soils 0.45

Highly erodible soils

0.4 to 0.5

Sandy loam soils 0.5

Moderately erodible soils

0.6

Silty loam soils 0.6

Low erodible soils

0.7

Firm loam soils 0.7

Stiff clay very colloidal soils

1.1

The flow velocity can be reduced by either:

x Reducing the depth of flow (increasing the width of the channel);

x Reducing the bed slope;

x Reducing the peak discharge (reducing catchment area); or

x Increasing channel roughness.



If the channel width, depth or gradient cannot be altered, then there are two options for controlling erosion as follows:

x Reduce the flow velocity through the placement of rock check dams;

x Increase the effective scour resistance in the channel through the placement of an effective channel liner such as rock or an appropriate liners.

3.5.4 Erosion control measures

Wells waste rock emplacement is designed to have a slope of 330 and maximum vertical distance of 10 m wide bench/erosion control structures (Omya, 2016). It is profiled to provide erosion control. The waste rock emplacement area will be progressively revegetated as necessary.

A list of potential erosion control techniques which con potentially be used across the site is provided in Table 3.3.

Table 3.3 – Summary of erosion control techniques

Technique Typical use

Cellular confinement systems

x Containment of topsoil or rock mulch on medium to steep slopes.

x Control erosion on non-vegetated medium to steep slopes such as bridge abutments.

Compost blanket x Used during the revegetation of steep slopes either incorporating grasses or other plants.

x Particularly useful when the slope is too steep for the placement of topsoil, or when sufficient topsoil is absent from the slope.

Gravelling x Protection of non-vegetated soils from raindrop impact erosion.

x Stabilisation of site office area, car parks and access roads.

Heavy mulching x Stabilisation of soil surfaces that are expected to remain non-vegetated for medium to long periods.

x Suppression of weed growth on non-grassed areas.

Light mulching x Control of raindrop impact erosion on flat and mild slopes. May be placed on steeper slopes with appropriate anchoring.

x Control water loss and assist seed germination on newly seeded soil.

Revegetation x Temporary and permanent stabilisation of soil.

x Stabilisation of long term stockpiles.

Rock mulching x Stabilisation of long term, non-vegetated banks and minor drainage channels.



3.5.5 Sediment control measures

Sediment dams are used on the site to trap sediment from disturbed area runoff. The sizes and locations of sediment dams are described in 5.3.5.

Due to the nature of the site geology, sediment generated by in-pit operations readily settles out of suspension. As demonstrated by the water quality data for pit discharges (see Section 2.5), the current sediment control system for pit discharges is highly effective in limiting suspended sediment to very low values.

The sediment control system at BMM has evolved over the period of historic operations. Any future modifications to site sediment controls should be undertaken to contemporary standards.

Supplementary sediment controls should be implemented where the sediment producing catchment is small or the potential for producing sediment laden runoff is low. A list of appropriate supplementary sediment control techniques is given in Table 3.4.

Table 3.4 – Summary of supplementary sediment control techniques

Technique Typical use

Rock filter dam x Locations where there is sufficient room to construct a relatively large rock embankment.

x The incorporation of a filter cloth is the preferred construction technique if the removal of fine grained sediment is critical (high maintenance).

Check dam sediment trap

x Supplementary sediment trap in minor concentrated flow areas.

x Trapping sediments in table drains and minor drainage lines

x Check dams may be constructed of rock, sand bags or compost filled socks

Buffer zones/ grass filter strips

x Mostly suited to sandy soils

x Can provide some degree of turbidity control while the buffer zone remains unsaturated.

Sediment fence x Supplementary device for sheet flow from minor catchment areas

x Suitable for all soil types

x Require maintenance after every runoff event.



4 Groundwater aquifers

4.1 OVERVIEW An assessment of groundwater in the vicinity of the BMM site, as presented below, has been undertaken by Australasian Groundwater and Environmental Consultants.

Data in this report is derived from the Queensland Department of Natural Resources and Mines (DNRM) database, the Environment Authority Amendment application (Omya, 2016) and Bajool Marble Quarry Final Void Water Balance (WRM, 2011).

4.2 GEOLOGICAL SETTING The geology of the mine site and regional surrounds comprises Lower Devonian volcanics of the Mt. Holly Formation and Upper Permian granodiorites. The topographically lower and flatter ground associated with Eight Mile Creek and Langmorn Creek (Figure 4.1) comprises Holocene alluvial deposits overlying the volcanic rocks (Geological Survey of Queensland, 1974). The marble deposit occurs within the volcanic succession in the elevated and steep topography of Mount Kelly and Mount McCamley.

4.3 REGIONAL GROUNDWATER AQUIFERS The regional groundwater setting has been derived from five surrounding registered bores and the Omya domestic bore. The bores were drilled into volcanic rocks at depths of 18 to 36 metres with static water levels of 5.7 to 15.2 metres below ground level (RL 70 – 80 mAHD), and small yields from 0.5 to 3.85 L/s. The water quality is fresh with electrical conductivity of around 800 to 890 µS/cm (about double that of the surface water of 400 µS/cm). Groundwater occurs in the volcanics and alluvium, and flows away from the mountainous region where it discharges into Eight Mile and Langmorn Creeks. The weathered and fractured rock of the volcanics and the alluvium combine to form a regional minor aquifer.

Table 4.1 – Details of regional registered bores within 3 km of the mine

Registered Number

Easting Northing Depth

(m)

SWL (m)

Conductivity (µS/cm)

Yield (L/s)

Strata Source

RN91070 260230 7365332 21.7 -14.2 833 1.5 Mt Alma Fm DNRM

RN91147 260098 7365406 36.58 -15.2 797 0.5 Mt Alma Fm DNRM

RN136719 261169 7367113 28.35 -8.53 890 3.85 Mt Holly Fm DNRM

RN151284 263103 7364268 18 -5.7 860 0.43 Volcanics DNRM

RN151285 262669 7364335 21 -8 800 0.62 Volcanics DNRM

Omya Domestic

260060 7364722 - -15 - - - Omya

Marble is not usually considered as a groundwater-bearing aquifer unless it contains fractures or has developed into a Karst aquifer. Karst topography is a landscape formed from the dissolution of soluble rocks such as limestone, dolomite, and gypsum. It is characterized by underground drainage systems with sinkholes and caves. This is because thermal re-crystallisation of limestone (calcium carbonate) into marble destroys the primary porosity of the rock matrix. In the Bajool Marble mine, there are fractures indicated in the pits which discharge groundwater during the wet season and dry up during the dry season. This indicates a shallow ephemeral groundwater system in the marble. There appears to be no development of karst features within the mine.



It is likely that groundwater occurs in very small quantities within fractures in the marble. A higher water table than observed in the surrounding bores (a groundwater mound) will naturally form under the topographically higher ground, and thus will contribute to the groundwater flowing towards the creeks.

Figure 4.1 – Location of bores within 3 km of Bajool Marble Mine

4.4 IMPACT OF MINING ON GROUNDWATER A small amount of ephemeral groundwater has been observed to discharge into the pits, together with surface runoff. The water is subsequently used for dust suppression on the mine roads and in processing the marble. Unused water accumulates in the pits and small amounts will likely infiltrate to the groundwater below the pit and eventually move out to the surrounding volcanic and alluvial aquifers.

The mining process is expected to have almost no impact on groundwater unless the floor of the pit reaches the groundwater table or a karst feature (cave) is intersected. At this stage, the potential for contamination of the groundwater increases. This could occur later in the mine life when the quarry floor extends to about RL 90 mAHD level (estimated).

4.5 ASSOCIATED WATER MONITORING Site observations indicate that groundwater inflows are ephemeral and occur only after periods of rain. To quantify the volumes of associated water entering the pits, the water level within pits could be surveyed and recorded weekly when water is stored, along with estimated pumping volumes estimated from pump hours. This data will be used to



estimate the portion of inflows to the pits which are from groundwater, through the use of the site water balance.



5 Mine site water balance

5.1 OVERVIEW The water balance model (OPSIM) represents the movements of water within the BMM surface water management system over time based on inputs and operating rules. It includes all inflows (e.g. rainfall, surface runoff, groundwater inflows) and outflows (e.g. evaporation, storage overflows, pumped outflows, site water usage, off-site releases) affecting the on-site storages.

A daily (time-step) simulation model was developed based on the schematisation of the BMM water management system for the mine site as shown in Figure 3.1 to assess the performance of the water management system and determine its ability to manage during a range of climatic conditions, including extended ‘wet’ and ‘dry’ periods.

The BMM OPSIM water model was used to determine:

x the overall water balance;

x mine water storage inventory; and

x frequency and volumes of controlled release from the quarries and uncontrolled release from the site water storages.

5.2 AVAILABLE DATA Long term daily rainfall data at Bajool from January 1889 to June 2017 was obtained from the Queensland Government DSITIA Data Drill Service. The rainfall data is an aggregate of nearby stations to BMM and is not from a single station.

5.2.1 Rainfall

Table 5.1 shows the mean monthly rainfall and annual rainfall at Bajool for the 128 year period of record (January 1889 to July 2017). The rainfall data indicates that BMM has a distinct dry and wet season, with a wet season from November through to March.



Table 5.1 – Mean monthly rainfall and evaporation

Months Mean monthly rainfall and lake evaporation (mm) (January 1889 to July 2017)

Rainfall Morton’s lake Evaporation

Jan 158.8 194.3

Feb 150.5 164.3

Mar 95.6 162.1

Apr 46.2 128.5

May 42.2 97.0

Jun 45.0 76.0

Jul 34.8 85.1

Aug 26.6 111.2

Sept 27.3 142.8

Oct 52.6 178.6

Nov 76.4 191.1

Dec 113.4 204.5

Annual 870 1,736

5.2.2 Evaporation

Table 5.1 shows the mean monthly and annual Mortons’ lake evaporation at Bajool for the 77 year period of record (1939-2017). The average annual Morton’s lake evaporation at BMM site is approximately 1,736 mm. Evaporation rates are generally higher than rainfall throughout the year.

Figure 5.1 – Mean monthly rainfall and lake evaporation at BMM, Jan 1889 to Jun 2017

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Mean monthly rainfall (mm)Mean monthly evaporation (mm)



5.3 WATER BALANCE MODEL

5.3.1 Simulation methodology

The simulation used the ‘forecast’ simulation type in OPSIM. To assess the effects of varying climatic conditions, the forecast model was run for 124 realisations (with each realisation corresponding to the 5 years mine life), using 128 years of climatic data available from January 1889 to June 2016. A different rainfall input sequence is applied to each realisation. The first realisation adopts climatic data from 1889 to 1893, the second from 1890 to 1894 and so on through the 124 years of simulated climatic data. A percentile analysis of the resultant realisations can then be undertaken at user-defined confidence intervals to assess the behaviour of the various storages over extended dry and wet periods, reflecting the full range of climatic conditions experienced in the last 128 years.

The operating rules and schematised plan for the water management system configuration is shown in Figure 3.1.

5.3.2 Catchment area

Table 5.2 and Figure 5.2 shows the adopted catchment and landuse areas draining to the relevant storages for the water balance model.



Table 5.2 – Adopted catchment area

Dam Catchment Area (ha)

Cleared Hardstand Natural Quarry Rehabilitated Stockpile Total

North Quarry 5.9 3.6 9.5

Old Waste Dump* 2.9 2.9

SD1 1.0 1.0

SD2 0.5 2.5 3.0

SD3 0.1 11.4 11.5

SD4 2.1 0.5 2.6

SD5 1.2 7.5 1.4 1.6 11.7

SD6 1.5 0.3 0.5 0.3 2.6

SD7 0.1 1.4 1.5

SD8 2.8 7.0 1.0 10.8

SD12 0.2 9.1 2.4 11.7

SD13 0.2 5.4 2.2 10.4 18.2

Wells Quarry 2.0 4.7 4.3 8.7 0.3 20.0

* The old waste dump is not included in the water balance model. The runoff from the old waste dump drains straight to a tributary of Eight Mile Creek, north of the BMM site.



Figure 5.2 – Catchment and landuse boundary



5.3.3 Catchment runoff

The AWBM model was used to represent the runoff characteristics of different land use types within local mine site catchments. AWBM uses a group of connected conceptual storages (3 surface storages and 1 groundwater storage) to represent a catchment. Water in the conceptual storages is replenished by rainfall and reduced by evapotranspiration. Simulated surface runoff occurs when these storages fill and overflow. The model parameters define the depth and relative area of each of the storages, as well as the rate of water flux between storages.

To accurately simulate the site water balance, it is necessary to define the runoff characteristics of the various catchment surface (land use) types. Table 5.3 shows the adopted AWBM parameters, taken from a previous investigation of the site water balance (WRM, 2011). Catchments across the site were characterised into the following land use types:

x Natural, representing areas undisturbed by mining;

x Cleared or pre-strip areas ahead of mining;

x Rehabilitated areas;

x Quarry; or

x Stockpiles, representing overburden materials.

It is recommended that the runoff characteristics of the mine site catchments be monitored to verify the adopted runoff characteristics for active spoil dumps and natural catchments to confirm the accuracy of the predicted results.

Table 5.3 – AWBM parameters for various catchment types

Parameter Natural Hardstand Cleared Quarry Stockpile Rehabilitated

A1 0.2 0.1 0.1 0.1 0.1 0.2

A2 0.4 0.9 0.9 0.9 0.9 0.4

A3 0.4 0 0 0 0 0.4

C1 60 4.1 4.1 4.1 4.1 60

C2 90 13 13 13 13 90

C3 180 0 0 0 0 180

BFI 0.15 0 0 0 0 0.15

Kb 0.953 0 0 0 0 0.953

Ks 0 0 0 0 0 0

5.3.4 Site water demands

The site water demands at BMM are from crusher plant and haul road dust suppressions of 3 ML/year and 4 ML/year, respectively. Water is pumped from the Northern Quarry to a storage tank where is it accessed by the onsite water suppression truck and pumped to the Crushing Plant as required.

5.3.5 Water storages

The sizes of sediment dams with unknown storage volumes were estimated from the dam surface area, assuming an average depth of 2 m. Details of storage volumes and catchment areas are shown in Table 5.4.



Table 5.4 – Storage catchment areas and volumes

Sediment Dam ID Surface Area (m2) Volume (m3) Catchment Area (ha)

SD 1* 68 642 1.0

SD 2* 51 2113 3.0

SD 3* 117 117 11.5

SD 4* 376 1147 2.6

SD 5* 192 192 11.7

SD 6* 60 60 2.6

SD 7* 27 27 1.5

SD 8* 27 27 10.8

SD 12* 917 515 11.7

SD 13* 605 1092 18.2

North Quarry 4900 27,000 9.5

Wells Quarry 4833 597,000 20.0

PWD* 405 405 -

* Not modelled

The assumptions for the water balance model are as follows:

x The pump rates between Wells Quarry to North Quarry and Wells Quarry to SD 12 is assumed to be 10 ML/d on the two separate pipelines. Wells Quarry will initially pump to North Quarry. In the event when North Quarry is at its maximum surface level (during extensive wet periods), Wells Quarry will stop pumping to North Quarry and start pumping to SD 12. Wells Quarry will pump back to North Quarry when North Quarry is no longer full.

x Seepage through the embankments is assumed to empty the sediment dams within a few hours and therefore are not explicitly modelled.

x Negligible groundwater inflows to the quarry pits;

x The water management system between the process water dam and crusher plant is a closed system. The process water dam is not included in the water balance model.

5.3.6 Model results

The interpretation of the results provides statistical analysis of the water management system’s performance over the 124 realisations with different climatic sequences.

The performance of the proposed water management system was assessed for five climatic conditions: very dry (99% confidence trace), dry (90% confidence trace), median (50% confidence trace), wet (10% confidence trace), and very wet (1% confidence trace) to provide a range of possible storage behaviours based on the 128 sequences of rainfall data modelled for the 5-year period. These confidence traces represent the following:

x The 99% confidence trace represents ‘very dry’ climatic conditions. There is a 1% chance that conditions will be this dry;

x The 90% confidence trace represents ‘dry’ climatic conditions. There is a 10% chance that conditions will be this dry;

x The 50% confidence trace represents ‘median’ climatic conditions and is the most likely scenario;



x The 10% confidence trace represents ‘wet’ climatic conditions. There is a 10% chance that conditions will be this wet; and

x The 1% confidence trace represents ‘very wet’ climatic conditions. There is a 1% chance that conditions will be this wet.

Whether a percentile trace corresponds to wet or dry conditions depends upon the parameter being considered. For site water storage, where the risk is that available storage capacity will be exceeded, the lower percentiles correspond to wet conditions. For example, there is only a small chance that the 1% percentile storage volume will be exceeded, which would correspond to wet conditions.

It should be noted that a percentile trace shows the likelihood of a particular value on each day, and does not represent continuous results from a single model realisation. For example, the 50% percentile trace does not represent the model time series for median climatic conditions.

5.3.6.1 Quarry pit overflows

The annual exceedance probability of North Quarry and Wells Quarry yearly overflow volume is shown in Figure 5.3. Pumping from Wells Quarry to SD 12 and North Quarry reduces the probability of Wells Quarry overflowing to 0%. North Quarry is likely to spill in most years. To reduce this spill volume, BMM should release water in accordance with the BMM EA in order to manage the water inventory.

Figure 5.3 – Quarry yearly overflow volume

Figure 5.4 and Figure 5.5 show the North Quarry and Wells Quarry stored water volume under the different climatic conditions. North Quarry will not be empty under dry climatic conditions and will always have stored water for the site demands. The Wells Quarry will have stored water under the wet and very wet climatic conditions and will be empty under the dry and very dry climate conditions.



Figure 5.4 – North Quarry daily volume under different climatic conditions

Figure 5.5 – Wells Quarry daily total volume under different climatic conditions

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1% Very Wet Climate 10% Wet Climate 50% Median Climate 90% Dry Climate 99% Very Dry Climate



6 Water Monitoring Plan

Monitoring at BMM site is required to assess the compliance of the water quality with the EA conditions and the objectives of BMM WMP. Monitoring will be undertaken by a qualified person in accordance with the methods described in the latest edition of the administering authority’s Monitoring and Sampling Manual 2009 (DEHP, 2010).

6.1 SURFACE WATER QUALITY Surface water quality monitoring includes on-site water storages, receiving water and release water monitoring based on the sites EA conditions. The event based sampling enables quantification of any pollutant loads from the site and their corresponding impact on the receiving water quality. The locations of the monitoring sites are detailed in the EA conditions. Samples will be taken from the following locations:

x End of pipe release points to measure the stormwater and pit water from the site. These locations will provide an indication of pollutants generated from the BMM site.

x Receiving water sites located both upstream and downstream of the mine to assess the impact of the BMM on the existing environment. EA receiving water sampling points are monitored in accordance the BMM EA following rain events (>50mm).

The water quality at the site should comply with the EA requirements. In the event that water quality is above the trigger levels specified in the EA, an investigation on the cause of the exceedance will be undertaken.

6.2 SURFACE WATER QUANTITY Monthly monitoring of surface water quantity parameters will be used to assess site water inventory. Surface water quantity monitoring parameters will include:

x Water levels in dams and pits;

x Water level and duration of overtopping during any water releases (to be used to estimate release volume);

x Pump hours for transfer of water between storages;

x Rainfall runoff and evaporation estimates using site weather station data; and

x Water consumption estimates.

The collected surface water quantity data will be used to track the site water balance and report on site water management as required under EA conditions.

6.3 GROUNDWATER QUALITY The mining process is expected to have almost no impact on groundwater unless the floor of the pit reaches the groundwater table or a karst feature (cave) is intersected. At this stage, the potential for contamination of the groundwater increases. This could occur later in the mine life when the quarry floor extends to about RL 90 mAHD level (estimated).

6.3.1 Groundwater Monitoring

In order to monitor the groundwater in the mine area in advance of intersection by the mining activity, an exploration borehole near the pit be converted to a monitoring bore by installing uPVC casing (50 mm dia.) and a slotted screen to a depth of approximately 100 metres below ground level. The monitoring bore should be checked for depth to groundwater and water quality at least quarterly, and assess the same parameters as surface water monitoring.



Survey of water levels in the pits and estimates of pumping volumes will be used to estimate the groundwater inflows (associated water) to the pit.



7 Emergency and Contingency Plan

7.1 OVERVIEW Emergency responses will be carried out as per BMM Emergency Response Plan managed under the Safety and Health Management System to assist in managing specific incidents. With respect to water management, the Emergency Response Plan is implemented for a range of potential emergency scenarios:

x Exceedance of design rainfall events;

x Failure of containment structures;

x Loss of electrical supply;

x Supply of critical equipment and spare parts;

x Access to critical control and monitoring points under all weather conditions.

x Assignment and communication of responsibility of actions (including execution, monitoring and reporting) to relevant BMM site personnel.

7.2 WATER RELEASES The risk of significant water impacts from the release of water from uncontrolled spills from extreme rain events is low. The Water balance model predicts uncontrolled spills from North Pit, however the water quality indicates a low risk of exceedance to EA water quality release limits.

In the event of unexpected downstream water quality impacts during a controlled release event, all controlled releases from the site should be discontinued immediately until the reasons for the impact are identified and rectified. Actions taken should be in accordance with the BMM EA conditions.

7.3 POST-EVENT MONITORING Dams and drains on the site should be inspected after any significant rainfall event. Drains and dam spillways should be checked for erosion damage and repaired if required.



8 Responsibilities and Review

The management and implementation of the water management plan is administered through the following personnel:

x Plant Manager – accountable for the application of the WMP;

x Plant Manager – responsible for the documentation and revisions of the WMP;

x Plant Manager – responsible for monitoring and auditing of the WMP;

x Contractors engaged to undertake work at BMM are responsible for implementation of the WMP;

x Plant Manager – responsible for the implementation of the WMP.

The WMP is a static compliance document. Yearly reviews will focus around the BMM’s record of complying with this document and outlining actions for the year ahead to ensure continued compliance. The document will only be altered when changes occur to the site operations which will result in changes to the management of water. The yearly review will be completed by a competent person and will be responded to by site outlining the actions as required under the Environmental Authority.

Condition F27 of the BMM EA states a review and report of the Water Management Plan must be prepared each year by an appropriately qualified person. The report must:

x Asses the plan against the requirements under Conditions F27 of this environmental Authority;

x Include recommended actions to ensure actual and potential environmental impacts are effectively managed for the coming year; and

x Identify any amendments made to the water management plan following the review.



9 References

ANZECC, 2000 Australia and New Zealand Environment and Conservation Council, October 2000, ‘Australian and New Zealand Guidelines for Fresh and Marine Water Quality’.

DEHP, 2012 Queensland Government Department of Environment and Heritage Protection, July 2012, ‘Preparation of Water Management Plans for Mining Activities’.

DEHP, 2013 Queensland Government Department of Environment and Heritage Protection, July 2013, ‘Environmental Protection (Water) Policy 2009, Fitzroy River Sub-basin Environmental Values and Water Quality Objectives’.

Geological Survey of Queensland, 1974

Geological Survey of Queensland, Australia 1:250,000 Rockhampton Sheet SF 56-13, First Edition, Queensland.

IECA, 2008 International Erosion Control Association (Australasia), November 2008. ‘Best Practice Erosion and Sediment Control’.

Omya, n.d. Omya Australia Pty Ltd, n.d., Plan of Operations.

Omya, 2016 Omya Australia Pty Ltd, 11 August 2016, ‘Supporting Information’.

WRM, 2011 WRM Water & Environment Pty Ltd, 15 September 2011, ‘Bajool Marble Quarry Final Void Water Balance’, report prepared for Omya Australia Pty Ltd


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