Section 2 Proposal Description

Transcription

1 Section 2 Proposal Description

2 2. PROPOSAL DESCRIPTION 2.1 Overview The Proposal comprises the construction, operation and closure of mining at the J5 and Bungalbin East iron ore deposits and associated infrastructure in the Mt Manning area north of Southern Cross. Mining will be undertaken from a total of three open-cut pits across two deposits using conventional drill and blast techniques followed by excavation, loading and transport to the ore stockyard. Stockpiled ore will be loaded onto haul trucks and transported 50 km south on dedicated haul roads to the existing ore processing facility at MRL s Carina operation. The processing facility dry-crushes and screens the ore to a suitable size for loading onto ore trains at the Mt Walton siding on the Trans-Australian railway line. The key characteristics of the Proposal are summarised in Table 2-1 and detailed in Table 2-2 and Table 2-3 in terms of the physical and operational elements of the Proposal. The key characteristics have been defined with reference to the Environmental Assessment Guideline for Defining the Key Characteristics of a Proposal (Environmental Protection Authority, 2012).The remainder of this section describes the Proposal in further detail. TABLE 2-1: KEY CHARACTERISTICS - SUMMARY OF THE PROPOSAL Proposal title Proponent name Short description Jackson 5 and Bungalbin East Iron Ore Project Mineral Resources Limited The Proposal is to construct and operate two open-cut iron ore mines, referred to as J5 and Bungalbin East, within the Mount Manning area. The Proposal is located approximately 100 km north of Southern Cross in the Yilgarn area of WA. The Proposal includes: three open-cut pits (one at J5 and two at Bungalbin East) three waste rock landforms haul roads supporting infrastructure for each mine include internal mine access roads, the ore stockpile area, site office, workshop, laydown area, explosive magazine, water bores, water storage dam (turkey nest) for potable and operational water supply, Waste Water Treatment Plant (WWTP), Reverse Osmosis plant (RO), power supply, fuel storage, hazardous materials storage area and landfill closure of both mines and rehabilitation of areas disturbed by mining and related activities. Issue Date: 31/08/2016 MRL-ENV-TS-RP-0047-Rev2 Page 2-1

3 TABLE 2-2: KEY CHARACTERISTICS PHYSICAL ELEMENTS Element J5 Bungalbin East Location Proposed extent Location Proposed extent Mine pit Figure 2-1 Section 0 Clearing no more than 61 hectares (ha) of native vegetation within a 2055 ha development envelope. Figure 2-1a Section 0 Clearing no more than 147 ha of native vegetation within a 2055 ha development envelope. Waste rock landform Figure 2-1 Clearing no more than 88 ha of native vegetation within a 2055 ha development envelope. Figure 2-1a Clearing no more than 98 ha of native vegetation within a 2055 ha development envelope. Supporting infrastructure Figure 2-1 Clearing no more than 47 ha of native vegetation within a 2055 ha development envelope. Figure 2-1a Clearing no more than 45 ha of native vegetation within a 2055 ha development envelope. Haul road Figure 2-1 Figure 2-1b Clearing no more than 57 ha of native vegetation within a 2055 ha development envelope. Figure 2-1a Figure 2-1c Clearing no more than 68 ha of native vegetation within a 2055 ha development envelope. TABLE 2-3: KEY CHARACTERISTICS OPERATIONAL ELEMENTS Element J5 Bungalbin East Location Proposed extent Location Proposed extent Waste rock volume Figure 2-1 Disposal of approximately 21 million tonnes of waste rock Figure 2-1a Disposal of approximately 70 million tonnes of waste rock Water abstraction Total abstraction of approximately 219,000 kilolitres per annum for construction and operational purposes. 2.2 Construction Construction will commence with clearing the centreline of the haul road, which will be subsequently widened to the full width of the haul road, inclusive of cut and fill requirements to maintain the design gradient. Locations of suitable gravel material for road construction will be identified within the development envelope and these areas cleared in preparation for excavation of this material. Topsoil and vegetation will be stockpiled in suitable locations for use in rehabilitation following the completion of mining. Issue Date: 31/08/2016 MRL-ENV-TS-RP-0047-Rev2 Page 2-2

4 750000mE mE mE mE mE Legend Disturbance area (Proposal) Development Envelope mN mN mN mN mN mN mN mN Sheet Layout Source: Infrastructure supplied by Mineral Resources (Apr 2016) Imagery: Landgate (2012) mE Figure: 600m Scale 1:30,000 MGA94 (Zone 50) Author: Mineral Resources CAD Ref: g2378_j5_be_per_c02_f02_01 Drawn: CAD Resources ~ Date: Jul 2016 Rev: D A4 Tel: (08) ~ Fax (08) THE PROPOSAL 2-1

5 760000mE Legend Disturbance area (Proposal) Development Envelope mN mN mE mN mN mN mN mN mN Sheet Layout Source: Infrastructure supplied by Mineral Resources (Apr 2016) Imagery: Landgate (2012) mE Scale 1:30,000 MGA94 (Zone 50) Figure: Author: Mineral Resources CAD Ref: g2378_j5_be_per_c02_f02_02 Drawn: CAD Resources ~ Date: Jul mE 600m Rev: D A4 Tel: (08) ~ Fax (08) THE PROPOSAL 2-1A

6 754000mE mE mE mE Legend Disturbance area (Proposal) Development Envelope mN mN mN mN Sheet Layout Source: Infrastructure supplied by Mineral Resources (Jul 2016) Imagery: Landgate (2012) mE mE mE mE m Scale 1:30,000 MGA94 (Zone 50) CAD Ref: g2378_j5_be_per_c02_f02_03 Date: Jul 2016 Rev: C A4 Author: Mineral Resources Drawn: CAD Resources ~ Tel: (08) ~ Fax (08) THE PROPOSAL Figure: 2-1B

7 758000mE mE mE Legend Disturbance area (Proposal) Development Envelope mN mN mN mN 4 Sheet Layout mN mN mN mN Source: Infrastructure supplied by Mineral Resources (Jul 2016) Imagery: Landgate (2012) mE m mE Scale 1:30,000 MGA94 (Zone 50) Author: Mineral Resources CAD Ref: g2378_j5_be_per_c02_f02_04 Drawn: CAD Resources ~ Date: Jul 2016 Rev: C A4 Tel: (08) ~ Fax (08) THE PROPOSAL mE Figure: 2-1C

8 Water for construction requirements may initially be sourced from the licensed production bores at the J4 and Carina mines, and the associated pipeline installed along the J4 haul road. Construction of the mines and supporting infrastructure will commence once the haul road has been completed to a sufficient standard allowing construction machinery to access the mine sites. Topsoil and vegetation will be stockpiled in suitable locations for use in progressive rehabilitation following the commencement of mining. 2.3 Operations Mine pits The J5 deposit will be mined from a single open-cut pit yielding a total estimated 13 to 32 million tonnes (Mt) of iron ore. The Bungalbin East deposit will be mined from two adjacent pits yielding a total estimated 52 to 83 Mt of iron ore. At the completion of mining, the area disturbed by the pits at J5 and Bungalbin East will be 61 ha and 147 ha, respectively. This disturbance area is inclusive of areas previously disturbed by historic land use as well as areas required during and/or after mining for: temporary storage of cleared vegetation that will be used for progressive and postmining rehabilitation temporary storage of harvested topsoil/subsoil that will be used for progressive and post-mining rehabilitation light vehicle access track between mine pits and stored vegetation and topsoil abandonment bunds where required for ongoing public safety of the area post mining. Mining will result in the removal of approximately 75 vertical metres of rock within the pit at J5 and approximately 115 vertical metres of rock within the southern (deepest) pit at Bungalbin East. Pit dewatering will not be required at either deposit as mining will not intersect the natural groundwater elevation of approximately 420 metres (m) Australian Height Datum (AHD) at J5 and 450 mahd at Bungalbin East. At Bungalbin East the southern pit will be mined first and then backfilled with waste rock from the northern pit. Backfilling of the southern pit is expected to raise the floor of the pit to about the same height as the eastern side of the pit crest (refer to Figure 12-2) Waste rock landforms Approximately 91 Mt of waste rock will be excavated during mining, comprised of approximately 21 Mt of at J5 and approximately 70 Mt at Bungalbin East. At J5 waste rock will be disposed of via two smaller Waste Rock Landforms (WRLs) adjacent to the pit. The WRLs are separated from each other and the mine pit by internal access roads. At Bungalbin East, waste rock from the southern pit will be disposed of via a single WRL containing approximately 33 Mt. Waste rock from the northern pit will be backfilled into the southern pit, comprising a volume of approximately 37 Mt. The WRL and associated access roads are located to avoid conservation significant plant species where possible. The conceptual design for the WRLs incorporates a single lift that is up to 45 m in height with concave slopes having a profile of 20 degrees at the crest grading to 15 degrees at the toe. If necessary, cells will be constructed within the centre of the WRLs to appropriately dispose of potentially acid forming or other hostile waste rock. Issue Date: 31/08/2016 MRL-ENV-TS-RP-0047-Rev2 Page 2-7

9 At the completion of mining the combined disturbance area of the WRLs at J5 and a Bungalbin East will be 186 ha, comprised of 88 ha at J5 and 98 ha at Bungalbin East. This disturbance area is inclusive of areas previously disturbed by historic land use as well as: temporary storage of cleared vegetation that will be used for progressive and postmining rehabilitation temporary storage of harvested topsoil/subsoil that will be used for progressive and post-mining rehabilitation light vehicle access tracks between the WRLs and stored vegetation and topsoil Supporting infrastructure Supporting infrastructure for each mine includes internal mine access roads, the ore stockpile area, site office, workshop, laydown area, explosive magazine, water storage dam (turkey nest) for potable and operational water supply, WWTP, RO plant, power supply, fuel storage, hazardous materials storage area and landfill. At the completion of mining the total area disturbed by supporting infrastructure at J5 and Bungalbin East will be 92 ha, comprised of 47 ha at J5 and 45 ha at Bungalbin East. This disturbance area is inclusive of areas previously disturbed by historic land use as well as temporary storage of cleared vegetation and harvested topsoil/subsoil that will be used for postmining rehabilitation of these areas Haul roads A total of 30 km of haul road will be constructed to connect the mine operations to the J4 haul road. The haul road network extends generally south from the deposits along L77/253 (incorporating a small diversion, being L77/270) to meet the J4 haul road on L77/254. At the completion of mining the total area disturbed by haul roads will be 125 ha, comprised of 57 ha at J5 and 68 ha at Bungalbin East. This disturbance area includes allowances for: 2.4 Closure temporary storage of cleared vegetation, topsoil and subsoil that will be used as part of post-mining rehabilitation gravel pits for road-base material as well as long-term maintenance of unsealed mine roads road drainage through the installation of v-drains and catch-ponds where necessary maintenance of surface water flow during flood events through the installation of pipes and/or culverts as necessary water pipelines and telecommunications infrastructure (e.g. fibre-optic cable and communications towers) as required. The closure phase of the Proposal comprises the decommissioning and removal of all built infrastructure and rehabilitation of all remaining disturbance associated with the Proposal. Rehabilitation and decommissioning will be undertaken in accordance with the Rehabilitation and Mine Closure Plan. Further detail on rehabilitation and decommissioning is provided in Section 12. In the interest of public safety, abandonment bunds will be constructed across mine roads and other access tracks that intersect the pits, to prevent the possibility of inadvertent vehicle access to these areas. Issue Date: 31/08/2016 MRL-ENV-TS-RP-0047-Rev2 Page 2-8

10 Where there is steep terrain and an absence of mine roads or access tracks the potential safety risk from inadvertent vehicular access is low, but allowance has been made for the construction of an abandonment bund within the disturbance area. MRL has consulted with the DMP regarding the positioning of abandonment bunds, noting that detailed geotechnical drilling to confirm the stability of the pit walls post mining has not been possible at this time due to access restriction. This geotechnical drilling will occur immediately following approval to confirm how close mining can safely approach the abandonment bunds thereby ensuring long-term stability of the final landform. 2.5 Existing facilities The Proposal will utilise existing facilities associated with the J4 and Carina operations, these being the J4 haul road, the Carina accommodation village, the Carina haul road, the Carina airstrip and the processing and rail load-out facilities at the Carina operation. A new accommodation village will be constructed at the intersection of the J4 and proposed Bungalbin East haul roads, outside of the MMHARCP. This village is approved under Ministerial Statement 988 in relation to the J4 proposal and the changes to that proposal approved under s45c of the EP Act. The village was not constructed to support the J4 operation for economic reasons. Whilst the new camp is under construction, the existing Aurora camp on M77/580 will be utilised to accommodate a construction workforce of up to 110 personnel, prior to the Aurora camp being decommissioned. Both the Carina and J4 mines and associated infrastructure operate pursuant to approvals obtained under relevant legislation. The aspects of these operations that are necessary for the implementation of the Proposal, such as the processing and rail load-out facilities, haul roads, accommodation village and airstrip can be managed under existing approvals under Part IV of the EP Act and therefore do not form part of the Proposal. 2.6 Alternatives considered MRL has undertaken a detailed evaluation of options or alternatives in locating, planning and designing the Proposal to mitigate environmental impacts. This evaluation began prior to the development of MRL s Carina operation in 2011, when strategic planning was undertaken with regard to the future development of all of MRL s iron ore deposits in the Yilgarn, including Carina Extended, Chameleon, Hunt Range, J4, J5 and Bungalbin East. The no development alternative is not a realistic proposition for MRL due to the significant investment it has made in the Yilgarn region for the benefit of shareholders, employees, local communities and the State of WA. In any case, the significance of residual impacts of the Proposal are not so great as to justify a no development decision. Exercise of the no development alternative is more appropriately achieved through Government policy. As no such policy exists in any tenements and their associated mineral exploration and mining entitlements that were to be relinquished by MRL would inevitably be secured by others. Mining of iron ore deposits in the Yilgarn is typically carried out using a central infrastructure hub, often attached to a mine, which receives and processes ore from one or more satellite mines in the region prior to rail load-out to a port facility. Haulage of ore from satellite mines to the central processing hub is typically done by haul trucks operating on a dedicated haul road, with rail transport inevitably being excluded on the basis of the relatively high up-front capital cost of construction that cannot be recovered over the life of the Proposal. By implementing the model outlined above, MRL is able to minimise the cumulative environmental impact of mining as ore processing facilities are not required to be constructed at Issue Date: 31/08/2016 MRL-ENV-TS-RP-0047-Rev2 Page 2-9

11 each satellite mine and other approved infrastructure such as segments of haul roads constructed as part of other proposals will be utilised. The haulage routes between J4, J5, Bungalbin East and MRL s central processing hub at Carina were carefully evaluated, particularly with respect to the MMHARCP. Two main haul routes were considered: Continue the Carina haul road in north-westerly direction to connect the Carina Extended, Chameleon and Hunt Range deposits and then in a westerly direction along the northern side of the Helena-Aurora Range to connect J4, J5 and Bungalbin East. Branch off the Carina Haul Road about 10 km south of the Carina mine in a westerly direction to connect with J4, with additional spurs along the way in a northerly direction to connect to J4 and Bungalbin East. The latter of these two options was ultimately selected on the basis that J4 would be developed first and that this option would minimise the extent of the haul road network, and therefore disturbance, within the MMHARCP. In doing so, the haulage distance between J4, J5, Bungalbin East and the central processing hub was increased at MRL s cost, in terms of the length of haul road to be constructed as well as the ore haulage distance. In terms of the sequence of development for the Proposal, it should be noted that the mines will be developed simultaneously once mining at J4 is complete. Ore from J5 is required to be blended with ore from Bungalbin East to achieve the correct product specification; therefore J5 is unlikely to be mined in isolation from Bungalbin East. MRL has invested considerable effort in site design and layout to optimise the Proposal so as to minimise environmental impact. The process of optimisation has focussed on the location and design of WRLs, supporting infrastructure and haul roads. This is because these elements, as compared to the mine pits, are more capable of being located and/or designed to avoid or minimise environmental impacts. The ore deposits, and the pits required to be excavated to recover these deposits, are fixed and cannot be located elsewhere. In direct response to stakeholder consultation, MRL has made several key changes to site design and layout optimisation since referral of the Proposal: The J5 WRL was initially a single WRL located further east than the current design. The eastern end of the WRL encroached upon a large drainage line and potentially could have impeded water flow following large rainfall events. The WRL was split into two separate WRLs, one either side of the main access road to the mine. This allowed the eastern WRL to be reduced in size so that it no longer encroached upon the drainage line. The western WRL was also redesigned to avoid populations of conservation significant flora. The Bungalbin East WRL was initially located immediately adjacent to the mine pit to reduce the waste haulage distance and therefore increase mine profitability. It has subsequently been repositioned further from the pit to minimise impacts on the landform, in this case the Helena-Aurora Range, as well as dense populations of conservation significant flora. The overall land disturbance area of the WRL at Bungalbin East has been decreased significantly from 176 ha to 98 ha. This is a result of rescheduling the mine plan to focus on the southern half of the Bungalbin pit early in the mine life to create a void for backfilling. Waste material from the northern half of the Bungalbin pit will then be hauled a shorter distance to backfill the void. This not only reduces the area and height of the waste dump, and hence the environmental impact, but also reduces the number of trucks required, improving the economics of the Proposal. MRL has successfully applied this strategy at Carina (also in the Yilgarn) and will also implement this strategy at Iron Valley in the Pilbara. This opportunity is Issue Date: 31/08/2016 MRL-ENV-TS-RP-0047-Rev2 Page 2-10

12 unlikely to be available at J5 where the vertical dip of the orebody means that backfilling would sterilise potential pit cutbacks (within the area proposed under this PER). Backfilling of all the waste cannot be achieved without rehandling of the entire waste rock volume after the extraction of all of the ore, an undertaking that would have an unsustainable negative impact on the economics of the proposal disproportionate to any environmental benefits of doing so. The area of disturbance comprising the mine pit at Bungalbin East was reduced to avoid a population of L. bungalbin (Priority 1). The elevation profile of all WRLs was revised from a traditional berm and batter arrangement to a single concave slope. At Bungalbin East, the shape of the WRL was also elongated from its initial circular shape. These changes are expected to provide a better aesthetic form that, coupled with appropriate landscape treatment post mining, will better blend with the surrounding topography. The extent of supporting infrastructure was decreased at both J5 and Bungalbin East by resizing the ROM pads and removing the evaporation ponds (as these ponds are not required as mining will occur above the groundwater table). The supporting infrastructure area at Bungalbin East was repositioned further west, which allowed the WRL at Bungalbin East to also be repositioned further to the southwest. Access roads between the pit and the WRL at Bungalbin East were redesigned to avoid populations of the threatened flora species Tetratheca aphylla subsp. aphylla. The mid-section of the J5 haul road was realigned further south to avoid a portion of a major drainage line with the same alignment i.e. the haul road was positioned within and parallel to the drainage line. Miscellaneous Licence L77/270 was applied for specifically for this reason. Overall, these changes have reduced the total area of direct disturbance (clearing) for the Proposal from 720 ha as referred to 611 ha as proposed. This includes a net reduction in the mine pit area at Bungalbin East from 149 ha to 147 ha. 2.7 Approach to environmental management A key principle of EIA in WA is the use of best practicable measures and genuine evaluation of options or alternatives in locating, planning and designing proposals to mitigate detrimental environmental impacts and to facilitate positive environmental outcomes and a continuous improvement approach to environmental management (Government of Western Australia, 2012). Best practicable measures are discussed below in the context of environmental management. Importantly, the achievement of best practices is greatly facilitated where proponents have an environmental management system in place, particularly if it is consistent with an international standard such as ISO (Environmental Protection Authority, 2003). To manage its impacts on the environment, MRL adopts a systematic management approach based on the international standard for environmental management systems (International Organisation for Standardisation, 2015). MRL s Environment and Community Policy 2016 is the cornerstone of this approach, a copy of which is contained in Appendix 1-A. The policy promotes sustainable environmental and community practices with a stated objective of no harm to the environment or adverse impacts on the communities within which MRL operates, beyond that which is necessary to conduct its business and is approved by Government. It commits to developing and implementing management systems that enable the company to conduct its business in a responsible and appropriate manner. Issue Date: 31/08/2016 MRL-ENV-TS-RP-0047-Rev2 Page 2-11

13 From this policy, MRL has developed a corporate Environmental Management Plan (EMP) to provide an overview of MRL s approach (Appendix 2-A). The EMP forms an important component of MRL s Environmental Management System as it outlines the Plan-Do-Check-Act (PDCA) model and how it applies at MRL. This model is a feature of the ISO 14001:2015 standard and has leadership as a central attribute. The PDCA model, as it applies to MRL, is described in Table 2-4. Routine policies and procedures developed at the corporate level will apply to the Proposal as well as Proposal-specific plans and procedures included with this PER or to be developed in the future e.g. in response to conditions of approval. Recognising the need to achieve best practice environmental management in relation to the Proposal, MRL is committed to certifying the EMS for the Proposal to the ISO standard within two years after commencing productive mining operations. TABLE 2-4: EMS MODEL COMPONENTS AND ACTIONS Component Actions Leadership Take accountability for effectiveness of EMS. Integrate EMS into MRL's business processes. Ensure the resources needed for the EMS are available. Promote continual improvement. Plan Establish environmental objectives, KPIs and processes necessary to deliver results in accordance with MRL s policy. Identify legal obligations. Do Develop and implement an EMP. Develop and implement systems and operational procedures, and work instructions. Identify and meet training needs. Identify responsibilities and accountabilities. Emergency preparedness and response. Check Measure progress against KPIs. Environmental monitoring programs. Auditing and inspection. Records control. Act Consider performance and take actions to continually improve. Issue Date: 31/08/2016 MRL-ENV-TS-RP-0047-Rev2 Page 2-12