Frances Creek Mine 2017-18 Water Management Plan€¦ · 2.3 HYDROGEOLOGY & GEOCHEMISTRY ... 3.1...

Frances Creek Mine

2017-18 Water Management Plan

Prepared for: Territory Iron Pty Ltd

Revision Description Author Reviewer Approved Date

A Final KJE BJM BJM 17/11/2017

B Revision to amend WMP updates and reporting requirements

KJE BJM BJM 08/12/2017

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TABLE OF CONTENTS 1.0 INTRODUCTION ..................................................................................................................... 1

1.1 Purpose .................................................................................................................................. 1

1.2 Scope ..................................................................................................................................... 1

1.3 Objectives ............................................................................................................................... 1

1.4 Term ....................................................................................................................................... 1

1.5 Legal & Other Requirements .................................................................................................. 1

2.0 SITE CHARACTERISTICS ...................................................................................................... 2

2.1 LOCATION AND CLIMATE .................................................................................................... 2

2.2 SURFACE DRAINAGE .......................................................................................................... 2

2.2.1 Regional Catchments ...................................................................................................... 2

2.2.2 Project Area Drainage ..................................................................................................... 6

2.3 HYDROGEOLOGY & GEOCHEMISTRY ............................................................................. 10

2.4 SITE ACTIVITIES ................................................................................................................. 10

2.5 BENEFICIAL USES .............................................................................................................. 10

3.0 WATER RESOURCES .......................................................................................................... 11

3.1 WATER SUPPLY ................................................................................................................. 11

3.2 SURFACE WATER RESOURCES ...................................................................................... 11

4.0 OPERATIONAL WATER MANAGEMENT ............................................................................. 13

4.1 DESCRIPTION OF WATER MANAGEMENT SYSTEMS .................................................... 13

4.1.1 Upslope Diversions ....................................................................................................... 13

4.1.2 Passive Treatment Systems ......................................................................................... 13

4.1.3 Drainage & Seepage Capture ....................................................................................... 13

4.1.4 Active Pumping, Treatment & Release ......................................................................... 14

4.3 EROSION & SEDIMENT CONTROL ................................................................................... 19

4.4 PROBABILISTIC WATER BALANCE MODEL ..................................................................... 20

4.5 PROGRAM IMPROVEMENT ............................................................................................... 21

5.0 EMERGENCY PREPAREDNESS & RESPONSE ................................................................. 22

6.0 MONITORING & MAINTENANCE ......................................................................................... 23

6.1 STATUTORY & OPERATIONAL MONITORING PROGRAM .............................................. 25

6.1.1 Rainfall & Meteorological Monitoring ............................................................................. 25

6.1.2 Surface & Ground Water Monitoring ............................................................................. 25

6.1.3 Biological & Stream Sediment Monitoring ..................................................................... 30

6.1.4 Trigger Values ............................................................................................................... 31

6.1.5 Neutralant Sludge ......................................................................................................... 31

6.2 MAINTENANCE ................................................................................................................... 32

6.2.1 Embankments, Drains and Structures .......................................................................... 32

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6.2.2 Pumping and Water Treatment Infrastructure ............................................................... 33

7.0 REPORTING AND PLAN REVISIONS .................................................................................. 34

7.1 Reporting .............................................................................................................................. 34

7.1.1 WDL 191-06 .................................................................................................................. 34

Approval Decision 2006-2550 .............................................................................................. 34

7.1.2 ............................................................................................................................................. 34

7.1.3 Additional Reporting ...................................................................................................... 34

7.2 Plan Revisions ...................................................................................................................... 35

8.0 COMMITMENTS .................................................................................................................... 36

9.0 REFERENCES ...................................................................................................................... 38

LIST OF TABLES

TABLE 1 MONTHLY AVERAGE RECORDED RAINFALL AND PAN EVAPORATION – PINE CREEK 2

TABLE 2 SUMMARY MEDIAN MINE-AFFECTED WATER QUALITY (2014 TO 2016) 12

TABLE 3 SUMMARY OF SURFACE WATER MONITORING PROGRAM 27

TABLE 4 SUMMARY OF GROUNDWATER MONITORING PROGRAM 29

TABLE 5 SITE SPECIFIC TRIGGER VALUES (WDL 191-06) 32

TABLE 7 SUMMARY OF COMMITMENTS 36

LIST OF FIGURES

FIGURE 1 REGIONAL LOCATION .............................................................................................................. 4

FIGURE 2 PROJECT AREA LOCAL DRAINAGE ........................................................................................... 5

FIGURE 3 SOUTHERN PROJECT AREA STORAGES AND DRAINAGE ........................................................... 7

FIGURE 4 NORTHERN PROJECT AREA STORAGES AND DRAINAGE ........................................................... 9

FIGURE 5 ACTIVE WATER MANAGEMENT SYSTEM ................................................................................. 17

FIGURE 6 WATER RELATED MONITORING LOCATIONS ........................................................................... 23

APPENDICES APPENDIX A APPROVAL DECISION 2006-2550

APPENDIX B WASTE DISCHARGE LICENCE WDL 191-06

1.0 INTRODUCTION

This Water Management Plan (WMP) has been developed as a component of the Mining Management Plan (MMP) for the Frances Creek Iron Ore Project (the Project). This WMP describes the current and planned water management for the Project and how potential environmental impacts associated with surface and groundwater are and will be managed during the current phase of the Project, including monitoring and reporting.

1.1 Purpose

The purpose of the WMP is to describe the water management system and the operational controls and strategies implemented by Territory Iron Pty Ltd (TIPL) to ensure efficient and effective management of water to control environmental impacts in accordance with regulatory requirements.

1.2 Scope

Mining and processing of iron ore ceased at the Project in late 2014 and the site is now under care and maintenance, with resumption of operations not planned for the term of this WMP. This WMP applies to the Project at its existing phase – i.e. under care and maintenance (including rehabilitation) and therefore differs significantly from previous WMPs prepared during the operational phase of the Project.

The WMP has been prepared by Hydro Engineering & Consulting Pty Ltd in consultation with TIPL personnel.

1.3 Objectives

The main objective of the WMP and the water management system is to ensure protection of the environmental values of Frances Creek and other watercourses downstream of the Project. A further objective is to assist in managing the long-term water-related liabilities associated with the Project.

1.4 Term

The term of this WMP is the 12 month period from 1 October 2017 to 30 September 2018 inclusive. A revision may be prepared in the interim to include the results of forecast water balance modelling (refer Section 4.4).

1.5 Legal & Other Requirements

The WMP addresses the Project approval requirements which include the WMP components of:

the MMP requirements of the Northern Territory Department of Primary Industry and Resources (DPIR) under the Northern Territory Mine Management Act (2012); and

Approval Decision 2006-2550 and subsequent March 2012 & October 2014 variations, issued by the Commonwealth Government Department of Environment and Energy, under the Environment Protection and Biodiversity Conservation Act 1999. A copy has been included as Appendix A.

The WMP also takes cognisance of, and complies where relevant, with the conditions of Northern Territory Waste Discharge Licence WDL 191-06, issued by the Northern Territory Environment Protection Authority (EPA), including the relevant Beneficial Use Declaration (refer Section 2.5). A copy of WDL 191-06 is provided as Appendix B.

2.0 SITE CHARACTERISTICS

2.1 LOCATION AND CLIMATE

The Project area is located approximately 25 kilometres (km) north of Pine Creek and 167 km south-east of Darwin in the Northern Territory (refer Figure 2-1). The area experiences a typical top end monsoonal climate, with a hot, humid wet season from approximately November to March and a dry season typically from May to September, with October and April comprising transitional months with variable rainfall. The nearest operational Bureau of Meteorology (BoM) rainfall station is located at Pine Creek (Station No. 14933), with records available since 1874. The long term average annual rainfall at this station is 1,141 mm – monthly averages are summarised in Table 11.

Pan evaporation records are available from the BoM Pine Creek Council (Station No. 14960), with records available since 2000. Annual pan evaporation for the period of available data averages approximately 2,410 mm – monthly averages are also summarised in Table 12.

Table 1 Monthly Average Recorded Rainfall and Pan Evaporation – Pine Creek

Month: Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year

Average Rainfall (BoM Station 14933 - mm): 279 248 199 52 7.5 2.3 2.0 1.4 8.2 43 114 214 1,141

Average Pan Evaporation (BoM

Station 14960 - mm): 177 160 180 189 195 183 198 223 234 257 222 202 2,410

2.2 SURFACE DRAINAGE

2.2.1 Regional Catchments

The majority of the Project area is located adjacent to Frances Creek and lies substantially within its upper catchment, except as noted below. Jasmine Creek, a small tributary of Frances Creek, is located in the northern portion of the Project area (refer Figure 2-2). Frances Creek drains to the Mary River approximately 22 km to the north-east near Mary River Station, at which point its catchment area is an estimated 158 square kilometres (km2). The Mary River flows northwards and drains into the Timor Sea approximately 140 km further north (refer Figure 2-1), with a total catchment area of approximately 8,100 km2 (1,987 km2 upstream of Frances Creek). A portion of the southern margin of the Project area drains to the catchment of Nellie Creek (refer Figure 2-2). Nellie Creek drains eastwards and then north to join the Mary River approximately 6 km south of the junction with Frances Creek.

During the operational phase of the Project, ore was transported by road to the Roney Rail Siding, which is located approximately 13 km to the south-west of the Project area, and is located in the headwaters of the McKinlay River catchment (refer Figure 2-1). The McKinlay River joins the Mary River near Annaburroo approximately 85 km north of the Roney Siding.

1 Data Source:

http://www.bom.gov.au/jsp/ncc/cdio/weatherData/av?p_nccObsCode=139&p_display_type=dataFile&p_stn_num=014933 – downloaded 16 May 2016.

2 Data Source: http://www.bom.gov.au/jsp/ncc/cdio/cvg/av?p_stn_num=014960&p_prim_element_index=34&p_display_type=statGraph&period_of_avg=ALL&normals_years=allYearOfData&staticPage= – downloaded 16 May 2016.

A satellite open cut pit was developed at Ochre Hills, approximately 8 km to the north of the Project area. This area is within the catchment of Maud Creek, which flows north-eastwards and into the Mary River approximately 18 km downstream of the junction with Frances Creek.

Figure 2-1 Regional Location

Timor Sea

Figure 2-2 Project Area Local Drainage

2.2.2 Project Area Drainage

The main Project area (shown in Figure 2-2) may be divided into a southern and a northern area. Figure 2-3 and Figure 2-4 show the layout of site storages and site drainage in these two areas. Site storages include former open cut pits, sumps and dams.

The following describes the main features of the southern Project area surface drainage system (Figure 2-3):

The largest open cut pit storage in this area is the FCA pit, comprising FCAN (north) and FCAS (south). The surface catchment boundary of the FCA pit is shown in Figure 2-3 and comprises predominantly the pit area, a portion of waste dump A (WDA) to the south and a small undisturbed area to the east of FCAS. A constructed diversion intercepts undisturbed catchment to the east of FCAN and directs this via a small ponded area (ST2) to the passive treatment system (refer below). The estimated capacity of the FCA pit is approximately 14,000 ML.

Drainage from WDA either reports to the headwaters of Frances Creek to the west (and to the passive treatment system – refer below), to FCAS or to the headwaters of Nellie Creek to the east. A small seepage sump to the north-west of WDA intercepts sub-surface seepage from WDA along a former drainage line. The WDA seepage sump includes an active water treatment system (Treatment Plant B) and forms part of the Project operational water management system (refer Section 4.1.4).

Drainage from areas to the west of the FCA pit, including the fuel storage and administration area, PP1, the former run-of-mine (ROM) and crusher pad areas and SP1, drain westwards into a series of ponds, voids and storages which form a passive treatment system, including P1, P2, P3, H11W, H11E, P4 and, ultimately, Frances Creek Dam (FC Dam). The FC Dam is the main non-open cut pit water storage in the Project area with an estimated storage capacity of 1,300 ML.

Drainage from the Valley Residue Storage Facility (VRSF) and the small undisturbed area to its east flows via H11E, H11W and P4 to FC Dam.

Smaller open cut pits H2 and FCC capture drainage from their immediate surrounds. FCC has very limited external catchment, while H2 has a small undisturbed area catchment to its east.

WDC was developed by backfilling the Helene 3 open pit with reactive waste rock from Helene 5/6/7. Clean water diversions redirect runoff from the undisturbed catchment to the east of WDC, northwards via the H2 waste rock landform and eventually to Frances Creek. The PAF waste cell was encapsulated with a NAF buttress and dry cover during 2016 to reduce infiltration of rainfall. The cover includes an infiltration storage layer (ISL) which has been vegetated, overlying a reduced permeability layer (RPL). The cover has been designed and constructed to absorb all rainfall. Waters excess to the storage ability of the ISL move laterally through the ISL, to a subsurface spoon drain on the upper surface of the RPL. From here, they migrate to the south to the FCC open pit. A well (H3MB001) has been established in the PAF cell to support observation of the chemistry and SWL of the PAF cell. This well can be fitted with a pump to remove excess AMD affected waters should the need arise.

Runoff from WDD reports via sediment dams around its perimeter to Frances Creek.

Figure 2-3 Southern Project Area Storages & Drainages

The following describes the main features of the northern Project area surface drainage system (Figure 2-4):

The main open cut pit storage in this area is the FCB pit. The catchment area of this storage is limited to predominantly the pit area. Some upslope diversion of undisturbed area occurs around the northern perimeter of the pit. Water can be pumped to FCB from other storages in the area (refer Section 4.1.4). The estimated current capacity of FCB is approximately 1,400 ML.

Jasmine West (JW) pit is located to the west of FCB and adjacent to Jasmine Creek with a small external catchment area. Water from JW pit can be pumped to a water treatment system (Treatment Plant A) located near the pit (refer Section 4.1.4).

Thelma 2 pit is located to the south-west of waste dump B (WDB) and includes a significant ex-pit catchment area (estimated to total 56 hectares [ha]) comprising predominantly undisturbed area.

Rosemary (ROS) pit captures drainage from its immediate surrounds with very little external catchment. Water from ROS pit can be pumped to Treatment Plant A located near the JW pit (refer Section 4.1.4).

The south-eastern portion of WDB (In-Pit) has been developed predominantly by backfilling a former open cut pit (Thelma Rosemary [TR] pit) located adjacent to (but separate from) ROS pit. This area comprises mainly the waste dump itself, with limited upslope catchment. The surface of the backfilled waste rock is permeable and therefore a significant proportion of rainfall tends to percolate into the backfilled waste rock (refer also Section 4.1.3) although visible surface drainage occurs in the wet season (refer Figure 2-4). A dewatering bore located in the backfilled pit is available to pump accumulated water to Treatment Plant A located near the JW pit (refer Section 4.1.4).

The north-western portion of WDB (Ex-Pit) generates runoff which reports via a former haul road ramp to the WDB Sediment Trap, formed by the haul road to the north of WDB. Between the WDB Sediment Trap and WDB (Ex-Pit) a small seepage sump has been established to capture and monitor seepage from WDB (Ex-Pit).

Creek flows in the area are predominantly ephemeral, however some appear to exhibit flow persistence which suggests a significant baseflow component. Locally, this is most notable in Frances Creek, which contains some semi-permanent waterholes, and may be related to naturally shallow groundwater levels and seepage from the FC Dam. Regional streamflow data3 for nearby streamflow gauging stations located on an upper tributary of the Mary River (Harriet Creek G8180252) and on the upper McKinlay River (G8180069) suggests similar behaviour, with streamflow recorded on 68% and 60% of days for these two stations respectively.

3 Source: https://nt.gov.au/environment/water/water-data-portal

Figure 2-4 Northern Project Area Storages and Drainage

2.3 HYDROGEOLOGY & GEOCHEMISTRY

Previous hydrogeological studies (Golder, 2013) have identified that there are three key hydrogeological units lying within shallow, weathered sequences which overlie deeper siltstone, shale and granitic rocks. Groundwater is likely associated with the porosity of each of these units. Groundwater recharge likely occurs by downward percolation of rainfall and ponded water to these weathered sequences, however high rates of evaporation/evapotranspiration (refer Section 2.1) result in only a small difference between net average surface recharge and discharge or leakage to the underlying deeper strata. Groundwater flow is considered to be mostly vertical, however lateral seepage flow may occur where near-surface sediments are present near drainage lines. In the deeper strata, groundwater flows are likely to follow surface topographic gradients, except near open cut pits, where flow will be toward the pits, until such time and if the pits fill to above the surrounding groundwater level. Other than the fractured/weathered surficial layers, the majority of the strata have low permeability, which reduces the risk of significant outflow from the pits if they fill to above the surrounding groundwater level (GHD, 2015a).

Potentially acid forming (PAF) materials have been identified to varying levels of acid forming capacity at various locations in the Project area. Acid Metalliferous Drainage (AMD), associated with the exposure and oxidation of sulphidic materials, has been identified in the pit walls of FCB and FCAN pits and in waste dumps WDC, WDB and some areas within WDA (GHD, 2015a). Drainage and seepage from these areas is closely managed (refer Section 0) and monitored (refer Section 6.0).

2.4 SITE ACTIVITIES

Mining and processing of iron ore ceased at the Project in late 2014 and the site is now under care and maintenance. Site activities comprise:

earthworks associated with rehabilitation activities (dry season);

active water management (refer Section 4.1.4);

environmental monitoring, including water related monitoring (refer Section 6.0); and

various maintenance activities.

2.5 BENEFICIAL USES

When determining the level of protection to assign to a natural system, consideration of environmental values, otherwise known as beneficial uses, is fundamental. Environmental values may be defined as “… particular uses of the environment that are important for a healthy ecosystem or for public benefit, welfare, safety or health…” (ANZECC/ARMCANZ, 2000). The Northern Territory Water Act (2013) defines seven different possible beneficial uses of water. In 2002, the following beneficial uses were declared for the Mary River including all tributaries, lakes, lagoons, swamps and marshes in the catchment.

Environment – to provide water to maintain the health of aquatic ecosystems. These comprise the animals, plants and micro-organisms that live in water, as well as and the physical and chemical regime with which they interact.

Riparian/rural stock and domestic which includes stock drinking water on downstream pastoral properties.

Cultural – to provide water to meet aesthetic, recreational and spiritual needs.

In 1989, a beneficial use of aquatic ecosystem protection was declared for the McKinlay River for the river reach in the vicinity of the Roney Siding.

3.0 WATER RESOURCES

3.1 WATER SUPPLY

The only current year-round use of water for the Project is for potable use and vehicle wash, with occasional use for dust suppression during earthworks associated with rehabilitation activities. Potable water supply is drawn from an old Frances Creek township bore (FCPB03 – registered bore RN 005 924), located approximately 1.5 km to the south-west of the Project area. No additional groundwater abstraction is planned. Construction water may be sourced when required from the FC Dam.

3.2 SURFACE WATER RESOURCES

The surface water resources in the Project area comprise (refer Figure 2-2):

the local creeks – namely Frances Creek, Jasmine Creek and their tributaries;

upslope diversions from areas unaffected by mining;

the FC Dam; and

the former mine open cut voids.

The FC Dam is the largest non-open cut void water resource in the Project area (refer Section 2.2.2 and Figure 2-2). Constructed in approximately 1971, the FC Dam receives runoff from the main (southern) Project area and the passive treatment system, providing final dilution and a monitoring location (refer Section 6.0). Overflow from FC Dam occurs to Frances Creek in the wet season and seepage occurs in the dry season. Recorded water quality in FC Dam since 2013 indicates near or slightly above neural pH and total dissolved solids (TDS) below approximately 240 mg/L.

Mine affected water comprises water that either accumulates in open cut pits, flows across or seeps through mine affected landforms (refer Section 2.2.2 for a description of Project area drainage). In terms of water management, mine-affected water may be broadly categorised as follows:

AMD low quality: pH less than approximately 2.5, elevated TDS and dissolved metals concentrations.

AMD medium quality: pH between approximately 2.5 and 5.0, moderate TDS (below approximately 1,000 mg/L) and moderate to low dissolved metals concentrations.

Non-AMD: pH above approximately 5.0, low TDS (below approximately 500 mg/L) and low dissolved metals concentrations but with possibly elevated total suspended solids (TSS).

These classifications are site specific and align with the manner in which each category is managed. Management involves:

AMD low quality: Minimise generation and contain;

AMD medium quality: Treat and release; and

Non-AMD: Passive release.

Median water quality at monitoring locations across the Project area from the start of the care and maintenance phase (2014) to early 2016 is summarised in Table 2, illustrating the above water quality categories.

Table 2 Summary Median Mine-Affected Water Quality (2014 to 2016)

Location pH TDS Sulphate Copper TSS WQ Category pH

Units No. of

Samples mg/L No. of

Samples mg/L No. of

Samples µg/L No. of

Samples mg/L No. of

Samples

FCB 2.40 12 1,930 12 2,100 11 4,550 12 <5 12 AMD Low

JW 3.10 14 800 14 795 14 895 14 <5 14 AMD Medium

ROS 2.70 13 890 13 900 13 1,500 13 <5 13 AMD Medium

FCAN 2.69 12 860 12 700 11 480 12 <5 12 AMD Medium

FCAS 7.45 14 338.5 14 210 13 6 14 <5 14 Non-AMD

H6/7 SEEP1*

3.19 4 1,060 4 1,072 4 1,100 4 <5 4 AMD Medium

FCC 5.45 8 54.5 8 28 7 1 8 53 8 Non-AMD

FC Dam 7.70 24 146 24 59 23 1 24 5 23 Non-AMD

* WDA Seepage Sump

4.0 OPERATIONAL WATER MANAGEMENT

4.1 DESCRIPTION OF WATER MANAGEMENT SYSTEMS

A number of measures are undertaken within the Project area to manage water. These are described in the following sub-sections.

4.1.1 Upslope Diversions

Diversion of drainage from upslope undisturbed areas around mine landforms occurs, including upslope of FCA, FCB and FCC pits (refer Figure 2-3 and Figure 2-4). This reduces runoff inflow to these pits and hence decreases their long-term water inventory as well as increasing the catchment that would otherwise report to downstream Frances Creek. That is, these diversions avoid or reduce the input of runoff from relatively undisturbed catchments to mine affected water storages (such as pit voids).

Diversions have been established at the eastern and northern margins of FCA pit (refer Figure 2-3). Upslope runoff water flowing west towards the FCA pit is diverted to the north and south via excavated channels. Water entering the northern diversion is directed to the north of FCA and then west via the stage 2 culvert (ST2 on Figure 2-3). Flow then occurs to Frances Creek via H11W, P4 and FC Dam. Runoff entering the southern diversion is directed to the south and out of the Frances Creek catchment. Flow exiting this diversion occurs to small headwater tributaries of Nellie Creek (refer Figure 2-2 and Figure 2-3), as does runoff from the south-eastern margins of Waste Dump A. Water quality is routinely monitored in these headwater tributaries (refer Section 6.0).

4.1.2 Passive Treatment Systems

A system of drains directs runoff from mine landforms in the southern Project area (including the VRSF, former ROM and crusher area) westwards into a series of ponds, former mine open cut voids and storages which form a passive treatment system (refer Figure 2-3) adjacent to and in the headwaters of Frances Creek. This includes P1, P2, P3, H11W, H11E, P4 and the FC Dam.

Drainage from the WDD pit area is directed to a number of sediment dams around its perimeter (refer Figure 2-3), while drainage from the surface of WDB is directed to the WDB Sediment Trap (refer Figure 2-4). Discharge from these sediment dams/traps in the wet season reports to Frances Creek. Frances Creek discharges from the Project area at FCDS05 and is monitored in accordance with WDL 191-06 administered by the EPA.

These systems are efficient at removing elevated suspended solids which is associated with non-AMD drainage (refer Section 3.2). Water quality is monitored at key locations in these systems (refer Section 6.0).

4.1.3 Drainage & Seepage Capture

Runoff from the majority of former open cut pits is captured within those pit voids (refer Section 2.2.2). For certain open cut pits, this controls the risk of discharge of AMD to the downstream environment. The following pits currently contain AMD (categorised as either medium or low quality – refer Section 3.2):

FCAN;

FCB;

WDC – backfilled H3 pit;

WDB (In-Pit) – backfilled TR pit;

ROS;

JW; and

Thelma 24.

In addition, runoff reporting to the FCC pit is also captured. Although monitored, water quality indicates that this can be categorised as non-AMD.

Seepage from the western portion of WDA is captured in the WDA seepage sump (refer Figure 2-3). The sump has a very limited surface catchment area. Collected seepage is managed as part of the active pumping and treatment system (refer Section 4.1.4).

In order to reduce the surface catchment of WDB reporting to the WDB Sediment Trap, earthworks undertaken during 2017 have directed surface runoff from both the In-Pit and Ex-Pit portions into ROS pit by redirecting drainage from the former haul road ramp near the western perimeter of the ROS pit catchment into the ROS pit – this is indicated by the large drainage arrow on Figure 2-4.

4.1.4 Active Pumping, Treatment & Release

An active management system has been developed to control the risks presented by AMD affected waters across the site. The system involves a network of drains, impounDPIRnts and pumped transfers. AMD affected waters are either held for long term storage or treated prior to release to the environment.

The active management system is shown in schematic form in Figure 4-1 and described below. Note that Figure 4-1 includes some pits that are not actively managed. These have been included in the probabilistic water balance model (refer Section 4.4) in order to predict their long term water levels.

Water treatment (comprising two identical treatment plants) involves dosing influent water with a 50% solution of sodium hydroxide directly into a pressurised discharge line in order to increase pH. The rate of dosing is automatically governed by the volumetric flow rate and the pH of the influent water, to obtain a target pH of between 6.5 and 7.0. A variable speed pump injects the sodium hydroxide solution. The dosing circuit comprises a programmable logic controller (PLC), a flow tube and pH meters on both the inlet and outlet of the injection point. TIPL personnel attend the plants at least daily whilst the units are in use, to check general operation and various process parameters (e.g. reagent and fuel inventories, influent and treated water quality). Operational experience gained over the last several years has demonstrated that by neutralising the acidity of the AMD affected waters, dissolved metals will precipitate out as oxides and hydroxides. By the time the water reaches the lower reaches of Frances Creek (in the vicinity of FCDS04), water quality is suitable to meet the requirements of WDL 191-06.

Southern Project Area

AMD affected waters collecting in the FCAN & FCAS (Helene 5/6/7) pits are held for long term storage. Probabilistic water balance modelling indicates that this is an appropriate long term approach. Monitoring of the receiving environment indicates that seepage losses from this landform are not having a deleterious impact. The transition to an equilibrium

4 Thelma 2 water quality is borderline AMD medium quality – recorded TDS and metals concentrations are low but pH is

typically between 4 and 5.

groundwater regime and its interaction with the receiving environment is the topic of an ongoing study.

The WDA seepage sump collects AMD affected drainage from the western portion of WDA. Water collecting in this sump is collected via submersible pumps and directed to Treatment Plant B for treatment (see above). Discharge of treated water is to either P1 (the passive treatment system, which ultimately reports to the FCD) in accordance with WDL 191-06 or to FCAS. Discharge to FCAS only occurs if the treated water quality is not adequate for release (ie pH not between 6.2 & 7.0). Water quality monitoring occurs at downstream locations on Frances Creek (refer Section 6.0) in accordance with WDL 191-06. The SWL in the WDA seepage sump is maintained below 150mRL to avoid spillage from the sump at 152mRL.

A bore has been installed into WDC (the backfilled H3 pit) to provide information on the accumulated water level and its quality. If required (in order to control risk of spill from WDC) pumping from this bore may occur in the future to FCAN.

Northern Project Area

AMD affected waters collecting in the FCB (Jasmine Central) pit are held for long term storage. Probabilistic water balance modelling indicates that this is an appropriate long term approach. Monitoring of the receiving environment indicates that seepage losses from this landform are not having a deleterious impact. The transition to an equilibrium groundwater regime and its interaction with the receiving environment is the topic of an ongoing study.

AMD affected waters collecting in the Thelma2 pit are held for long term storage. Probabilistic water balance modelling indicates that this is an appropriate long term approach. Monitoring of the receiving environment indicates that seepage losses from this landform are not having a deleterious impact. The transition to an equilibrium groundwater regime and its interaction with the receiving environment is the topic of an ongoing study.

The WDB seepage sump collects AMD affected drainage from the WDB Ex-Pit landform. Water collecting in this sump is collected via pump and transferred to the Rosemary pit for interim storage. Operation of the pump is controlled by level, whereby the SWL is kept at least 1.0m below the crest of the impounDPIRnt. The sump is inspected at least daily during the wet season.

AMD affected waters collecting in the Rosemary pit are held for interim storage. Sources of AMD include the WDB seepage sump, runoff from the Rosemary pit highwall, seepage from WDB and surface runoff from WDB. A pontoon mounted pump is available to transfer waters from this location to Treatment Plant A or to the Jasmine West pit. The operating strategy is to run the pump so that the SWL is as low as possible and within the constraints of treatment plant capacity. The SWL in the Rosemary is always maintained below 175mRL as spill is anticipated at 177mRL. The pit is inspected at least daily during the wet season.

AMD affected waters collecting in the Jasmine West pit are held for interim storage. Sources of AMD include seepage through PAF waste rock located on the floor and southern wall of the pit void. Clean-water input from Jasmine Creek adds to the AMD affected inventory as does pumped flows from the Rosemary pit. Waters collecting in the Jasmine pit is collected via a skid mounted diesel pump and directed to Treatment Plant A for treatment (see above). Discharge of treated water is to Jasmine Creek pursuant to WDL 191-06 or to FCB. Discharge to FCB only occurs if the treated water quality is not adequate for release (ie pH not between 6.2 & 7.0). Water quality monitoring occurs at downstream locations on Jasmine

and Frances Creeks (refer Section 6.0), including continuous monitoring at the JCDS station for EC, pH, SWL & turbidity. Water quality samples are collected weekly during plant operation and analysed for a suite of parameters including metals in accordance with WDL 191-06. The SWL in the Jasmine West pit is maintained between 155 & 161mRL. A SWL of 163mRL is likely to result in seepage into Jasmine Creek.

A bore has been installed into WDB (In-Pit) to provide information on the accumulated water level. If required (in order to reduce the total stored AMD inventory) pumping from this bore may occur in the future to Treatment Plant A, with discharge of treated water to either Jasmine Creek or FCB, depending on the treated water quality and in accordance with WDL 191-06.

Figure 4-1 Active Water Management System

Management of mine affected water in the Northern Project Area is somewhat constrained by available storage and treatment capacity. Storage availability varies with prevailing rainfall conditions. Treatment capacity is limited to pumping to Treatment Plant A from one storage at a time and the treatment rate decreases with influent pH. As a result, pumping to Treatment Plant A is prioritised: water from ROS pit first priority and JW second priority. In the event that the water level

in JW becomes elevated while still treating water form ROS pit, untreated water from JW is pumped directly to FCB.

The overall active water management strategy is driven by the need to control the AMD spill risk. This includes treating and releasing water categorised as AMD medium quality (refer Section 3.2) in order to reduce the inventory of AMD water stored in Project water storages – particularly those with lower capacity. The water management strategy also involves the capture and storage of water categorised as AMD low quality. Storage of AMD low quality water occurs in FCB. The water in FCAN may be categorised as AMD medium quality and therefore it could be treated for release, however the water level in FCAN is relatively low (approximately 63 m below spill level as at mid-2016) and an assessment using a probabilistic water balance model (refer Section 4.4) indicates that the long term equilibrium water level in FCA should remain below spill level, therefore there should be no need to treat water for release.

Critical control levels for the primary dirty water storages are defined in Table 5. Pump start/stop levels have likewise been informed by the probabilistic water balance model and are indicated as ‘low’ and ‘high’ levels. A level below the ‘low’ or above the ‘high’ would represent a deviation from normal operations requiring some type of intervention. This may include equipment maintenance or mobilisation of additional resources. Excursions below ‘low-low’ or above ‘high-high’ would indicate a system failure. In many instances this would represent a reportable event.

Table 3: Trigger Action Response Plan

Storage Low-Low Low High High-High

Jasmine Central (FCB) 150 155 165 172

Jasmine West (JW) 150 153 157 160

H67SEEP (WDA Seep) 193 196 197 198

WDBSEEP 160 161 162.5 163

Rosemary Pit (ROS) 160 167 172 174

Helene 5/6/7 (FCA) 155 160 165 180 - All figures are in mRL

4.3 EROSION & SEDIMENT CONTROL

Management of erosion and generated sediment is an important aspect at the Frances Creek mine. Erosive forces can act to degrade structural elements such as encapsulation covers and excavation high-walls. In addition, sedimentation can lead to habitat disturbance (e.g. by burial) and other deleterious effects such as weeds establishment. Perhaps of most significance is that erosion can give rise to degraded surface water quality by adding turbidity or toxicants (e.g. dissolved metals) to the receiving environment.

The potential for erosion and the generation of sediment in the Project area is limited because mining activities have ceased. The generation of sediment can however occur as a result of on-going rehabilitation earthworks and erosion of existing mine landforms (e.g. waste dumps).

A number of factors can contribute to erosion and sediment generation, these include:

High rainfall intensity: Being situated in a seasonally dry/wet tropical climate, the Project area is often subjected to high intensity rainfall following a long dry season. Events exceeding 100 mm in 24 hours are not uncommon – the 1:2 annual exceedance probability 24 hour rainfall for the Project area is estimated to be 121 mm.

Relatively high levels of disturbance: Mining development has resulted in a significant disturbance envelope, particularly as waste rock landforms. These disturbed landforms are much more susceptible to the effects of erosion.

High levels of topographic relief: Much of the waste rock inventory at Frances creek has been placed in landforms characterized by elevated landforms and steep slopes. These steep gradients generally increase the risk of environmental effects due to erosion.

Erosion and sedimentation at the site is managed by the implementation of a combination of design mitigation and preventative control measures:

Design Measures:

Drainage from upslope undisturbed areas is diverted around disturbed landforms where practicable (refer Section 4.1.1); and

Haul road surfaces are compacted and comprise material with low potential for generating sediment.

Mitigation Measures:

Site drainages are directed to a network of sediment dams/traps for the purposes of reducing suspended solids in runoff (refer Sections 2.2.2 and 4.1.2);

Drainage from disturbed areas with a moderate-high potential to generate runoff with elevated suspended solids is directed to holding storages for assessment or treatment prior to release;

Water management structures including diversions, drains, sediment dams/traps and pit voids are subject to routine inspection and maintenance as required (refer Section 6.2); and

Monitoring of downstream water quality is routinely undertaken and includes TSS (refer Section 6.0).

Preventative Measures

TIPL has commenced a program of works aimed at reducing the extent of the disturbance envelope within the Project area. This program commenced in 2015 and is expected to continue through until 2020. Works undertaken during 2016 include rehabilitation of approximately 20 ha

of exploration drill pads within the Frances Creek catchment and revegetation of approximately 14 ha of the VRSF surface. Works planned for 2017 include revegetation of the southern and western batters of Waste Dump A (25 ha) as well as an encapsulation cover for Waste Dump C (10 ha). Also, planned for 2017 is the redirection of surface runoff from Waste Dump D (upper section) into the VRSF. This will result in runoff from approximately 8 ha of catchment being directed to the FC Dam (via H11E & W) rather than to Frances Creek via sediment dams.

4.4 PROBABILISTIC WATER BALANCE MODEL

A probabilistic water balance model is currently being developed to simulate the storages and transfers shown in Figure 4-1. The model has been used to forecast the water balance behaviour of these storages for a 20-year forward planning period from late 2016 onwards. The model simulates 127, 20 year “realizations” derived using the available regional historical climatic record from 1889 to 2016. The first realization uses climatic data from 1889-1909, the second 1890-1910, the third 1891-1911, and so on. The results from all realizations are used to generate water storage volume estimates and other relevant water balance statistics. This method effectively includes all recorded historical climatic events in the water balance model, including high, low and median rainfall periods. Predicted storage volumes are derived for all 127 realizations and the results used to generate volumes corresponding to different probabilities or risks of occurrence – e.g. median (50th percentile) and 10th/90th percentiles.

The model has been developed using the GoldSim® simulation package and operates on a smaller than daily time-step. The model simulates the behaviour of water held in, reporting to and pumped between all simulated water storages shown in Figure 4-1. For each storage, the model simulates:

Change in Storage = Inflow – Outflow

Where:

Inflow includes rainfall runoff (including seepage), groundwater inflow (for open cut pit voids) and all pumped inflows from other storages.

Outflow includes evaporation, spill, groundwater outflow and all pumped outflows to other storages or discharge.

Model historical climatic data (rainfall and evaporation) has been sourced from ‘Data Drill’ generated climatic data for the Project location. The Data Drill is a system which provides synthetic data sets for a specified point by interpolation between surrounding point records held by the Bureau of Meteorology (refer Queensland Government, 2016).

The Australian Water Balance Model (AWBM) (Boughton, 2004) has been used to simulate runoff from rainfall on the various catchments and landforms across the Project area storage catchments. The AWBM is a nationally-recognised catchment-scale water balance model that estimates catchment yield (flow) from rainfall and evaporation. Different sub-catchment types (based on surface characteristics) each with different AWBM parameters have been defined from available aerial photography. Surface and sub-surface (seepage) catchments have been estimated from available topographic contours. Model rainfall-runoff parameters for each sub-catchment were derived as part of model calibration using monitored site data for 2015-16. Full details are provided in the Water Balance Model report (HEC, 2017).

Storage volumes simulated by the model are used to calculate storage surface area (i.e. water area) based on storage level-volume-area relationships for each water storage – derived from available

topographic data. Storage surface areas are used to calculate evaporation on a daily basis from Data Drill evaporation data multiplied by an appropriate pan factor.

Estimates of groundwater inflow and outflow rates for three of the larger modelled pit voids: FCA, FCB and JW were provided by Big Dog Hydrogeology (2016). These were then adjusted as part of model calibration (HEC, 2017).

Full details of model forecasts for each of the simulated storages are contained in Water Balance Model report (HEC, 2017). The following summarises key model forecast results:

The simulated water level for both FCA voids (north and south) is predicted to continue to rise gradually with time and the two voids are likely to combine into a single water body, but in the longer term the water level should remain well below the external spill level of RL 204m. However, within the 20 year forecast period, the water level is likely to reach RL 180m whereupon groundwater outflow is forecast.

FCB water levels are likely to remain below the estimated spill level of RL 175.4m, with the 95th percentile of predicted water levels (i.e. levels that only have a 5% probability of being exceeded) not rising to more than within 3.3 m of the spill level. Note that modelling assumes no on-going pumping of water to the FCB void.

The simulated water level in the JW void fluctuates seasonally but the 95th percentile of predicted water levels is not predicted to rise above RL 160m assuming that Treatment Plant A remains in operation (RL 160m is the modelled trigger level for commencing pumping to Treatment Plant A) – i.e. 9.5m below the estimated spill level for this void.

Similarly the modelled future water level in the ROS void fluctuates seasonally but the 95th percentile of predicted levels is not predicted to rise above RL 172m assuming that Treatment Plant A remains in operation (the modelled trigger level for pumping to Treatment Plant A is RL 171.5m) – i.e. 5.5m below the estimated spill level for this void.

An update of the water balance model calibration and forecasts is planned during 2017.

4.5 PROGRAM IMPROVEMENT

On 5 April 2017 TIPL submitted an application to undertake field trials to assess the suitability of using an alternate neutralant in future water treatment programs. Qualified approval to undertake the trial was granted on 5 May 2017. The trials are scheduled for Q2 & Q3 2017 and involve the use of crushed limestone (ag-lime) to neutralise acidity in concert with, or in lieu of liquid caustic soda. Full details of the trial can be found in the MMP amenDPIRnt application and results from the trial will inform future versions of this water management plan. The trials will necessitate routine water monitoring of both surface and ground-waters in the vicinity of the Jasmine West Pit. In addition, routine monitoring of the build-up and environmental risk associated with any sludge association with the neutralisation process will be required. Section 6 of this plan has been amended to support the 2017 field trials.

5.0 EMERGENCY PREPAREDNESS & RESPONSE

In the event of an emergency that results in, or has the potential to result in, a release of contaminants to the environment that is not in accordance with WDL 191-06, or is likely to result in monitored water quality that exceeds Site Specific Trigger Values (refer Section 6.1.4), TIPL will demonstrate environmental responsibility by:

managing all emergency situations on accordance with the TIPL Emergency Response Plan;

taking all reasonable and practicable measures to prevent or minimise environmental harm; and

notifying the DPIR, the EPA and potentially affected landowners as required of the potential emergency and measures being undertaken to minimise the potential impact.

TIPL may seek written direction from the Minister for Land Resource Management, in accordance with Section 97 of the Northern Territory Water Act (2013), to discharge a contaminant into the environment where:

it is necessary and reasonable to release the contaminant because of an emergency; and

there is no other practicable alternative to the release.

Specific emergency scenarios that relate to water management include:

major release of hydrocarbons outside of containment areas;

unplanned or uncontrolled release of contaminants into the surface water environment; and

major failure of a water containment or water management structure (e.g. FC Dam, upslope diversion).

6.0 MONITORING & MAINTENANCE

TIPL undertake a year-round monitoring program relating to water resources in and around the Project area. Figure 6-1 shows the surface water monitoring locations and Figure 6-12 shows the groundwater monitoring locations.

Figure 6-1 Surfacewater Monitoring Locations

Figure 6-2: Groundwater Monitoring Locations

6.1 STATUTORY & OPERATIONAL MONITORING PROGRAM

Monitoring is carried out with the following objectives:

monitor the total stored water inventory;

monitor the effects of drainage from mined landforms on water quality (surface and groundwater);

assess the effect of rehabilitation activities on water quality;

provide records of the quality of water reaching the downstream environment;

enhance the understanding of natural water quality in the Project area;

assess impact on downstream environmental values;

provide a warning of potential adverse water quality impacts to allow them to be addressed by appropriate management measures;

record changes in water quality in response to rainfall events in the wet season and in the longer term; and

provide feedback to enhance water management measures.

The minimum requirements for water-related monitoring are given in WDL 191-06. TIPL undertake additional monitoring to ensure that these requirements and the above objectives are met.

Water sampling is undertaken in accordance with TIPL’s Surface Water Sampling Procedure and Groundwater Sampling Procedure. These procedures cover equipment calibration, field sampling procedures, laboratory analysis procedures and data entry. Sampling and field analysis is undertaken by trained TIPL Environmental personnel. Field analysis is undertaken using a water quality meter which is calibrated prior to use. Field parameter data is recorded in specific spreadsheets for entry into a water management database and transcribed to laboratory chain of custody forms. Laboratory certificates of analysis and quality control interpretation reports are reviewed by TIPL personnel prior to entering the data into the water management database.

6.1.1 Rainfall & Meteorological Monitoring

Three (3) automatic rainfall stations (tipping bucket pluviometers) are located as follows (refer Figure 6-1):

adjacent to Frances Creek at FCDS01;

adjacent to Frances Creek, north of Jasmine Creek at FCDS04; and

at the WDC northern soil moisture monitoring tree.

In addition, a manual rainfall gauge is located near the Project administration office. This gauge is read each day when rainfall occurs.

The suite of parameters to be monitored by each AWS will include air temperature, relative humidity, wind speed and solar radiation. These parameters will allow calculation of daily evaporation. The two locations will allow comparison of evaporation at a typical above-ground location and in-pit. This will provide useful data for on-going water balance modelling.

6.1.2 Surface & Ground Water Monitoring

Surface water monitoring locations are shown in Figure 6-1. A summary of the monitoring locations and parameters monitored are provided in Table 4.

In addition, monitoring of water level is undertaken at least on a weekly basis (during the wet season)at the following monitoring locations (refer Figure 6-1): ROS, H67SEEP1, WDCSP, TRSP02, TSF, T2, FCB FCAN, FCAS, FCESP, H11W, FCC and TRSP01.

Groundwater monitoring locations are shown in Figure 6-1. A summary of the monitoring locations and parameters monitored is provided in Table 5.

Full breakdown of the specific analyte suites for the surface and groundwater testing regimes is provided in Table 5.

Table 4 Summary of Surface Water Monitoring Program

Program Sites Parameters Frequency

Continuous Monitors

FCDA08 FCDS01 FCDS04 JCDS

Standing Water Level Turbidity pH EC & Temperature

Continuous

FCDASpillway FCB

Standing Water Level Continuous

WDL -Release

Frances Creek

FCDA08 FCDS04 FCDS05 FCUS05

Field Parameters: Laboratory Parameters: Major Cations: Major Anions: Nutrients: Total & Filterable Metals: Speciated Arsenic: Total Cyanide:

24 hours after commencement of release, then weekly

Jasmine Creek

JCDS JC-Discharge FCUS-Alt

Roney Creek

RSSP01 MRDS02 MRDS06

Operational Creeks

Maude Creek

MCUS02, MCDS01 Field Parameters: Laboratory Parameters: Major Cations: Major Anions: Nutrients: Total & Filterable Metals:

Jan, Apl, Jul, Oct Dec, Feb, Mar Nellie Creek NLTRIB02

Frances Creek

FCDS01 FCDS04 FCDS05 FCUS05 FCDA08

Jasmine Creek

JCDS02

Operational Sites

Levels FCAS FCAN JW ROS TRSP02 H11W

Standing Water Level Dec – April (twice weekly) May – Nov (Monthly)

Dirty Water Inventory

FCAS FCAN H67SEEP1 FCC FCB JW ROS T2 H11W TRSP02 OHPIT

Field Parameters: Laboratory Parameters: Major Cations: Major Anions: Nutrients: Total & Filterable Metals:

Jan, Apl, Jul, Oct Dec, Feb, Mar

Sediment Traps

FCDA03 TSF WDD01 WDD02 WDD03 WDD04 FCESP WDCSP H11W TRSP01 TRSP03


Jan

Special Projects

Drain from WDC to FCC pit


Following rainfall with aim to collect four (4) samples per season

Table 5 Summary of Groundwater Monitoring Program

Program Sites Parameters Frequency

WDL Groundwaters Frances Creek FCMB10 Field Parameters: Laboratory Parameters: Major Cations: Major Anions: Nutrients: Total & Filterable Metals: Total Fluorine:

Jan, Apl, Jul, Oct Roney Siding MRMB01

Groundwater Chemistry Potable Water Bores FCPB02, FCPB03 Field Parameters: Laboratory Parameters: Major Cations: Major Anions: Nutrients: Total & Filterable Metals: Total Fluorine:

Full Parameters – Jan, Apl, Jul, Oct GWL - Dec, Feb, Mar

Helene 5/6/7 H567WRD2, SPP

Helene 1/2/3 H1, H2, EM1 H2MB02, H2MB04, H3MB-001, H3MB-002

TSF VMB02, VMB03, VMB04

Jasmine Thelma FCMB02, FCMB04 THR1, THR2, TH3 JA0, JA2, JA3, JA4, JA5B JA6, JA7

Maude MCMB01

Groundwater Level Helene 1/2/3 H2MB03, H2MB05, H2MB06

GWL Jan, Apl, Jul, Oct Dec, Feb, Mar Jasmine Thelma RJ1, RJ2

TH2 FCMB06, FCMB07

Table 6: Analysis Suites

Suite Parameters Unit

Field Parameters: SWL/GWL, pH, EC, Temperature, Turbidity, DO, Redox Potential

Laboratory Parameters: pH, EC, Temperature, TDS (calc), Turbidity, TSS, Total Hardness (as CaCO3)

Major Cations: Ca, K, Na µg/L

Major Anions: Cl, SO4, CO3/HCO3 µg/L

Nutrients: TP,FRP, TN, NH3, NOx µg/L

Total & Filterable Metals: Al, As, Be, Cd, Cr, Co, Cu, Fe, Pb, Mg, Mn, Mo, Ni, Se, Tl, Sn, U & Zn.

µg/L

Speciated Arsenic: As (III), AS (V) µg/L

Total Cyanide: CN µg/L

Total Fluorine: F µg/L

Standing Water Level: SWL mRL

Groundwater Level: GWL mRL

6.1.3 Biological & Stream Sediment Monitoring

The aims of the aquatic biological monitoring program are as follows:

Characterise aquatic fauna and flora communities, aquatic habitat, water quality and sediment quality within and downstream of the Project area;

Use the data collected on aquatic fauna and flora communities, aquatic habitat, water quality and sediment quality to assess whether or not there is any evidence of impacts associated with the Project; and

Assess trends in aquatic fauna and flora communities, aquatic habitat and water quality over time to characterise inter-annual variability and determine if there is any evidence of changes at potentially impacted sites indicative of longer-term impacts to the receiving aquatic environment that can be associated with the Project.

The aims of the stream sediment monitoring program are as follows:

Characterise the sediment chemistry;

Use the data to assess the fate of metals leaving the Project area; and

Compare data against sediment quality guidelines.

Monitoring is undertaken by specialist consultants on an annual basis post wet season and has occurred since 2007. Field methods include habitat assessment, water quality sampling and analysis, sediment sampling and laboratory analysis (including total metals) and surveys of periphyton, macroinvertebrate and fish communities. Subsequent analysis includes statistical analysis of data (including AUSRIVAS assessment) and comparison to previous annual monitoring. Monitoring occurs at sites on downstream Jasmine Creek, Frances Creek, Maud Creek and the McKinlay River. The most recent monitoring program was completed in 2015 (GHD, 2015b). The monitoring report concluded that there was no evidence of any potential impacts of discharge from the Project area on sediment quality, there was no evidence to suggest the Project had altered chlorophyll–a concentrations, had led to deterioration in the condition of macroinvertebrate communities or to suggest an impact on the health or diversity of fish communities.

The 2016 monitoring program (being undertaken by the Centre for Tropical Water and Aquatic Ecosystem Research – James Cook University) includes an aquatic biological condition assessment in parallel with a review of water quality in order to revise/update site specific trigger values (refer Section 6.1.4).

6.1.4 Trigger Values

WDL 191-06 lists water quality site specific trigger values (SSTVs) for Frances Creek downstream surface water monitoring point FCDS05 and Roney Siding surface water monitoring points MRDS02 and RSSP01 (refer Figure 6-1). Water quality monitoring results for these three sites are compared to the SSTVs upon receipt of laboratory results. Any exceedances of SSTVs are required to be reported to the EPA (refer Section 7.0). SSTVs do not represent ‘compliance limits’. In the event of exceedance of any of the above triggers, TIPL undertakes the following actions:

investigate possible direct causes or contributing factors – e.g. earthworks, spills, water releases, intense rainfall;

examine results from other monitoring locations to assess the possible source or cause;

implement remedial measures or management actions to address the cause if this has been determined and, if practicable, to prevent re-occurrence;

initiate an investigation if the cause cannot be determined and is not attributable to non-Project related causes;

assess the likely risk of environmental harm – this includes the annual aquatic biological and stream sediment monitoring program (refer Section 6.1.3);

revise trigger criteria if appropriate; and

undertake reporting as appropriate (refer Section 7.0).

During periods of release of treated water, exceedances of the SSTV values may occur at site FCDS05.

The SSTV values for FCDS05, which are summarised in Table 7, have been developed by TIPL based on recorded background water quality and have been accepted by the EPA. These SSTVs are being reviewed by TIPL as more data becomes available (refer also Section 8.0) and the veracity of the values is expected to increase with time.

No ‘site specific’ trigger values have been developed for Roney Siding surface water monitoring sites MRDS02 and RSSP01 because of the limited water quality data available – the locations are remote from the main Project area and flow occurs only during and following periods of rainfall, which limits the opportunity for sampling. Instead the SSTVs for these two locations have been set in WDL 191-06 to ANZECC/ARMCANZ (2000) guideline values for protection of aquatic ecosystems at the 95% level of protection. These values are also included in Table 7. These SSTVs are being reviewed by TIPL as more data becomes available.

6.1.5 Neutralant Sludge

The in-pit water treatment trials scheduled for 2017 and perhaps beyond have introduced a new risk related to the sludge that results from the neutralisation process. It is expected that sludge will build up on the floor of the Jasmine West pit. There is a risk that this material will build up substantially or may be prone to remobilisation. TIPL is currently in discussion with TropWater (consultants who are engaged to undertake the stream sediment survey) to design a suitable monitoring program for this material.

Table 7 Site Specific Trigger Values (WDL 191-06)

Parameter Units Site Specific Trigger Value

FCDS05 Roney Siding MRDS02 & RSSP01*

pH pH units min 6.0; max 8.0

Electrical Conductivity µS/cm 250

Dissolved Oxygen % saturation min 85; max 120

Al µg/L 94 55

As µg/L 13 13

Be µg/L 0.13 0.13

Cd µg/L 0.2 0.2

Cr µg/L 1.0 1.0

Co µg/L 2.8 2.8

Cu µg/L 1.4 1.4

CN µg/L 7 7

Fe µg/L 300 300

Pb µg/L 3.4 3.4

Mn µg/L 1,900 1,900

Mo µg/L 34 34

Ni µg/L 11 11

Se µg/L 11 11

Tl µg/L 0.03 0.03

Sn µg/L 3.0 3.0

U µg/L 0.5 0.5

Zn µg/L 8 8

Turbidity NTU 27 15

Total Suspended Solids

mg/L 20 20

Total P mg/L 0.01

Total N mg/L min 0.20; max 0.30

Ammonia mg/L 2.57

Nitrogen Oxides mg/L 0.01

* Per ANZECC/ARMCANZ (2000) guideline values for protection of aquatic ecosystem (95% level of protection).

6.2 MAINTENANCE

6.2.1 Embankments, Drains and Structures

Pre and post west season inspections of drainage infrastructure are undertaken by TIPL personnel to ensure their integrity and function. Infrastructure inspected includes (refer Section 2.2.2) open drains/channels, diversion, culverts, dam embankments, spillways, sediment dams and waste dump surfaces. Where infrastructure integrity is compromised (e.g. blockages of culverts, excessive scour of drains, build-up of sediment) repairs are implemented as required by an earthmoving contractor.

6.2.2 Pumping and Water Treatment Infrastructure

The following checks, maintenance and monitoring of active pumping and treatment infrastructure is undertaken on a daily basis when operational:

that the pumps, generators and water treatment systems are operational and maintained according to manufacturer’s instructions;

ensure that there is no leakage of sodium hydroxide from the treatment infrastructure;

records of time of start and stop of pumping and cumulative (totalizer) flow meter readings at start and stop;

check integrity of pump lines at pump start or each day (when running continuously) to ensure no leakage is occurring outside the mine affected water storage catchments; and

monitoring of storage water level (source and destination storages).

7.0 REPORTING AND PLAN REVISIONS

7.1 Reporting

7.1.1 WDL 191-06

The following summarises reporting required by WDL 191-06 to the EPA:

1. Any exceedances of SSTVs (as soon as practicable after occurrence), including identification of potential contributing factors, likely risk of environmental harm and any management actions undertaken.

2. An Annual Audit and Compliance Report by 31 October each year, per the proforma supplied as Appendix 3 in WDL 191-06.

3. An annual monitoring report by 31 May each year and by 31 October 2016. The report must:

follow the EPA “Guidelines for Consultants Reporting on Environmental Issues”;

include a tabulation of monitoring data required by the WDL;

include a trend analysis and interpretation of the monitoring data;

include a long term trend analysis (minimum period of three years) to demonstrate any environmental impact;

summarise any SSTV exceedances;

demonstrate that any SSTVs above ANZECC/ARMCANZ (2000) guideline values provide ecosystem protection; and

provide results of the investigation into Jasmine Creek surface and groundwater interactions.

7.1.2 Approval Decision 2006-2550

The following summarises reporting required by Approval Decision 2006-2550 to the DoEE:

1. Any unplanned events which may impact water quality in the project area;

2. An Annual Report on this WMP and the measures contained herein; and

3. A Compliance Certificate accompanied by an independent audit report of compliance with the conditions of approval. An example of the Compliance Certificate can be found at http://www.environment.gov.au/epbc/publications/annual-compliance-report-guidelines.

7.1.3 Additional Reporting

In addition, TIPL also undertake the following reporting:

1. In the event of exceedances of triggers given in Section 6.1.4, TIPL also informs the following organisations and individuals of the exceedance and actions being undertaken:

the EPA;

the DPIR;

the DoEE

the Traditional Landowner Liaison Committee; and

the affected landowner.

2. Quarterly water quality monitoring reports to the DPIR.

3. Annual biological and stream sediment sampling reports to the DPIR.

7.2 Plan Revisions

The WMP is to be reviewed and revised on an annual basis (refer Section 1.4).

Annual revisions of the WMP and subsequent interim revisions shall be submitted to the DPIR and DoEE for review and approval annually in accordance with Frances Creek Mine Project Authorisation 0479-01 and Approval Decision 2006-2550 respectively.

8.0 COMMITMENTS

The 2014 WMP provided a number of commitments – many of which related to the then operational Project. Table 8 below provides this list of commitments and reconciles these against actions undertaken or provides an update to the commitment based on the care and maintenance status of the Project.

Table 8 Summary of Commitments

Number 2014 WMP Commitment Resolution or Update

1 TIPL will clear sediment traps each dry season if they are more than half filled. For those located in areas that may have been impacted by AMD, excess sediment is either used in-situ to increase the height of the walls between each cell of the sediment traps or if the sediment is to be removed, it will be removed and placed inside an active PAF cell.

TIPL will clear sediment traps each dry season if they are more than half filled. For those located in areas that may have been impacted by AMD, excess sediment is either used in-situ to increase the height of the walls between each cell of the sediment traps or if the sediment is to be removed, it will be removed and placed inside an active PAF cell or open cut void.

2 TIPL will provide an updated water model prior to the 2014/2015 wet season.

Water balance model is being revised in 2016 using probabilistic approach.

3 TIPL will revise the SSTVs using additional data collected during the 2013/2014 wet season prior to the 2014/15 wet season.

SSTVs being revised by 2017 based on biological condition assessment in parallel with a review of water quality.

4 TIPL will validate the flow rating for each continuous monitor during the 2014/15 wet season.

Rating to be facilitated at FCDS01 and JCDS by installation of downstream control weirs. Remaining sites’ rating considered impractical but will continue to monitor stream level to provide indication of flow occurrence.

5 TIPL will use water from Pond 2, Helene 11 West and the Rail Sediment Dam or other appropriate water sources as operationally required for dust suppression along the Haul Roads.

TIPL requirement for dust suppression is limited to rehabilitation earthworks – water will be sourced from FCA Pit South.

6 TIPL will provide an updated conceptual groundwater model which will be used to assist the investigation into the water quality at JA2 and VMB03.

Scheduled for 2017.

7 TIPL will investigate bore integrity at VMB03. Scheduled for 2017.

8 TIPL will develop and implement a risk assessment procedure for environmental risks to be completed by Q4 2014.

An updated environmental aspects and impacts register will be provided in the Frances Creek Mine 2016 MMP.

9 TIPL will ensure that PAF is contained appropriately to make sure that it does not generate acid mine drainage with the potential to cause downstream environmental degradation.

Addressed by WMP – refer Section 4.1.

10 TIPL will inspect all water storage and treatment structures as soon as practicable following extreme rainfall events and repaired as necessary.

Addressed by WMP – refer Section 4.1 and 6.2.

11 TIPL will install flow gauges on pump infrastructure by Q4 2014 for accurate management of abstraction.

No extensive abstraction during care and maintenance so no longer relevant.

12 TIPL will derive SSTVs for groundwater at WDL compliance bores prior to the 2014/15 wet season.

SSTVs being revised by 2017 based on biological condition assessment in parallel with a review of water quality.

Table 7 (Continued) Summary of Commitments

Number 2014 WMP Commitment Resolution or Update

13 TIPL will investigate the source of the iron floc observed in waterways during the 2014 Aquatic Biological Monitoring Program.

On-going area of investigation during annual biological monitoring programs, including the 2016 program.

14 TIPL will produce a Data Entry Standard Operating Procedure for application prior to the 2014/15 wet season.

During late 2014 a database was developed for the storage, collation and management of all water monitoring data (surface and groundwater lab and field results). This includes an operating procedure for data entry, manipulation and retrieval.

15 TIPL will investigate the possibilities of streamlining government reporting requirements to fit with site operational requirements.

Two strategies implemented: a) A summary water data spreadsheet was developed

including pivot tables for manipulation of data (back to 2013).

b) Investigation of software package for management of water and other environmental data – decision on software to be undertaken in 2016.

9.0 REFERENCES

ANZECC/ARMCANZ (2000). “National Water Quality Management Strategy Paper No. 4 - Australian and New Zealand Guidelines for Fresh and Marine Water Quality”. Australian and New Zealand Environment and Conservation Council and Agriculture and Resource Management Council of Australia and New Zealand, October.

Big Dog Hydrogeology Pty Ltd (2016). “Territory Iron Site Wide Groundwater Flow Review”. Draft Report, Rev A, November.

Boughton W.C. (2004). “The Australian Water Balance Model”. Environmental Modelling & Software, Vol. 19, pp 943-956.

GHD (2015a). “Frances Creek Operations Hydrogeological Review and Acid Mine Drainage Assessment”. Report 43/22324 prepared for Territory Iron Pty Ltd, July.

GHD (2015b). ““Frances Creek Mine Biological Monitoring Program 2015”. Report 23/15496 prepared for Territory Iron Pty Ltd, June.

Golder (2013). “Hydrology Review – Frances Creek Operations – Territory Resources”. July.

HEC (2017). “Frances Creek Mine GoldSim Water Balance Model”. Report prepared for Territory Iron Pty Ltd by Hydro Engineering & Consulting Pty Ltd, January, Rev D.

Queensland Government (2016). “SILO Climate Data”. Department of Science, Information, Technology and Innovation, http://www.longpaddock.qld.gov.au/silo/

APPENDIX A

Approval Decision 2006-2550

APPENDIX B

WASTE DISCHARGE LICENCE

WDL 191-06

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