narrabri coal mine – modification change to underground

ASSESSMENT REPORT

NARRABRI COAL MINE – MODIFICATION Change to Underground Mine Geometry (08_0144 MOD 5)

1 BACKGROUND The Narrabri Coal Mine is an underground mine located approximately 28 kilometres (km) southeast of Narrabri and 28 km northwest of Boggabri in the New England North West Region (Figure 1). It is located to the northwest of the mining precinct centred within and around the Leard State Forest, which includes the Boggabri, Maules Creek and Tarrawonga Coal Mines.

Figure 1: Location of the Narrabri Coal Mine

Narrabri Coal Project – Modification 5 Environmental Assessment Report The Narrabri Coal Mine is operated by Narrabri Coal Operations Pty Ltd (NCO) on behalf of the Narrabri Joint Venture in which Narrabri Coal Pty Ltd is the major shareholder. Narrabri Coal Pty Ltd is a wholly owned subsidiary of Whitehaven Coal Limited. The mine operates under a project approval which was granted under delegation from the Minister for Planning in July 2010 (MP 08_0144). This approval has been modified on three prior occasions and allows: • extraction of up to 8 million tonnes per annum (Mtpa) of run-of-mine (ROM) coal from 26 longwalls

with a maximum width of 295 metres (m), until the end of December 2031; • construction and operation of a coal handling and preparation plant (CHPP), rail spur, rail loop, and

load out facility; • processing and stockpiling of coal; and • transportation of product coal by rail to the port of Newcastle. NCO commenced longwall mining in 2012. To date, extraction from three longwall panels has been completed and mining of the fourth longwall panel is underway. Recently NCO reviewed options for improving operational efficiency to increase coal production using the existing infrastructure and equipment, and identified that changes to the underground mine geometry would allow for an increase in the ROM coal production rate. Currently the relocation of a longwall machine from a completed longwall panel to the next longwall panel (change-out) suspends operations for 6-8 weeks each year. By increasing the longwall panel widths from the approved 295 m to 400 m, the period between longwall machine change-outs would increase, thereby increasing the maximum amount of coal that could be extracted within a calendar year from 8 Mtpa to 11 Mtpa. 2 PROPOSED MODIFICATION NCO is seeking a further modification to the approval under Section 75W of the Environmental Planning and Assessment Act 1979 (EP&A Act) to: • reduce the number of longwall panels from 26 to 20; • increase the longwall panel widths of 14 of the remaining longwall panels from 295 m to 400 m; • move the underground mine footprint approximately 60 m to the west; • increase the maximum extraction rate of ROM coal to 11 Mtpa; • increase the average number of daily train movements from 3 to 4 trains per day; and • make minor changes to ancillary infrastructure. Although approval was only granted for a 21 year operational mine life, the original environmental assessment identified that mining of the seam at a maximum extraction rate of 8 Mtpa would take 28 years. However, an increase in the maximum annual production rate would allow the additional coal reserves to be extracted with no change to the approved operational life of the mine. A comparison of the existing and proposed changes to the underground mining area layout is summarised in Table 1 and depicted in Figures 2, 3 and 4. The proposed modification is described in detail in the Environmental Assessment (EA) submitted in support of the application (see Appendix C).

Department of Planning and Environment 2

Narrabri Coal Project – Modification 5 Environmental Assessment Report

Table 1: Comparison of Approved and Modified Operations Aspect Existing/Approved Operations Proposed Operations

Project Life • Mining approved until July 2031. • Unchanged. Tenement • Mining operations conducted within Mining

Lease (ML) 1609. • Unchanged.

Mining Method • Longwall mining of the Hoskissons Seam. • Unchanged. Underground Mine Geometry

• Twenty six longwall panel (LW101 to LW126).

• A reduction in the number of longwall panels from 26 to 20.

• 295 m wide longwall panels. • An increase in longwall panel widths for LW107 to LW120 from 295 m to 400 m (LW101 to LW106 unchanged).

• Western extension of the underground mine footprint relative to the existing/approved underground longwall mine footprint of approximately 60 m.

ROM Coal Production

• Total ROM coal production of approximately 170 Million tonnes (Mt).

• ROM coal production of up to 8 Mtpa

• Total would remain unchanged. • Peak annual ROM coal production would

increase to approximately 11 Mtpa. Subsidence Commitments and Management

• The subsidence impact performance measures listed in Conditions 2 and 3, Schedule 3 of Project Approval 08-0144.

• Unchanged.

Underground Mine Surface Infrastructure

• Ventilation shafts, pre-drainage and goaf gas drainage sites, mine safety pre-conditioning sites (LW101 to LW105), access roads and electricity transmission lines.

• Unchanged. • Mine safety pre-conditioning sites would be

developed in LW106 to LW120.

Coal Washing • Coal Handling and Preparation Plant (CHPP) and secondary crusher/screen capable of processing approximately 2,000 tonnes (t) per hour.

• Unchanged.

Coal Handling and Stockpiling

• ROM coal stockpile capacity of 700,000 t. • Product coal stockpile capacity of 500,000 t.

• Unchanged.

Coal Reject Management

• CHPP rejects emplaced in Rejects Emplacement Area.

• Unchanged.

Product Coal Transport

• Product coal transported to Newcastle by rail. • Peak of 8 trains per day (trains/day). • Average of 3 trains/day.

• Increase in the average number of trains from 3 trains/day to 4 trains/day.

• Peak number of trains/day unchanged. Water Management

• Conducted in accordance with the Water Management Plan

• Minor amendments to the site water management system.

Water Supply • Make-up water demand to be met from mine dewatering, runoff recovered from operational areas, and licensed extraction from Namoi River and Namoi River Alluvium

• Unchanged.

Hours of Operation

• 24 hours per day, seven days per week. • Unchanged.

Employment • Operational workforce of approximately 370 employees.

• Unchanged.

Surface Development Footprint

• Approximately 750 hectares (ha). • Unchanged, although the location of underground mine surface infrastructure would potentially change to reflect the changes to the mine geometry.

• The number of ventilation shafts would decrease from 10 to 7.

Rehabilitation Strategy

• Conducted in accordance with the Landscape Management Plan.

• Unchanged.



Figure 2: Approved Longwall Geometry



Figure 3: Proposed Longwall Geometry



Figure 4: Proposed Change to Underground Mine Footprint


Narrabri Coal Project – Modification 5 Environmental Assessment Report 3 STATUTORY CONTEXT 3.1 Section 75W

Although Part 3A of the Environmental Planning and Assessment Act 1979 (EP&A Act) was repealed, the approved operations of the Narrabri Coal Mine remains a “transitional Part 3A project” under Schedule 6A of the EP&A Act. Consequently, the proposed modification is being considered under the former Section 75W of the EP&A Act, in accordance with the relevant savings provisions. Based on its assessment, the Department is satisfied that the application can be characterised as a modification to the existing approval (rather than a new project in its own right) as: • the proposed activities would be consistent with the approved activities; • there would be no alteration to the mining method; • additional infrastructure would be contained within the approved pit top area; • total life-of-mine production would remain the same; and • there would be no significant increase in the environmental impacts of the project. 3.2 Approval Authority

The Minister for Planning was the approval authority for the original development application and is the approval authority for this modification application. However, under the Minister’s delegation dated 16 February 2015, the Director, Resource Assessments may determine the application, as NCO has not made reportable political donations, Narrabri Shire Council did not object to the modification, and no public objections were received. 3.3 Environmental Planning Instruments

In accordance with Section 75I of the EP&A Act, the Department has considered the modification against the provisions of relevant environmental planning instruments, and is satisfied that none of these instruments substantially govern the carrying out of the modification. 4 CONSULTATION

The Department exhibited the modification application from 29 September 2015 until 16 October 2015 and made the accompanying EA publically available on its website and at the Department’s Information Centre, Narrabri Shire Council and the Nature Conservation Council. The Department also consulted with relevant Government agencies. None of these agencies objected to the proposed modification. Some agencies made comments that are summarised below: The Division of Water within the Department of Primary Industries (DPI Water) advised that discrepancies in post mining groundwater recovery related to increased permeability and storage should be rectified in future modelling. DPI Water also noted that NCO: • would need to ensure adequate water entitlement is sourced well in advance of requirements; • would need to provide “make good” provisions for impacted bores; and • should continue to monitor subsidence impacts on all nearby watercourses and mitigate impacts as

required. DPI Water was satisfied that these issues could be addressed in a revision of the approved Water Management Plan, as required under the existing project approval conditions. The project approval condition also requires regular review and re-calibration of the groundwater model in consultation with DPI Water. The Environment Protection Authority (EPA) raised concerns about potential under-estimation of predicted noise levels in view of recent noise exceedances and the proposed increased utilisation of equipment. While this is a compliance issue for the existing approval, NCO has committed to implementing real time noise monitoring and associated trigger, action response plans to ensure noise limits are met at all privately owned receptors. The EPA is satisfied with these measures.


Narrabri Coal Project – Modification 5 Environmental Assessment Report The Office of Environment and Heritage (OEH) raised no objections to the modification, noting that the additional vegetation area that would be impacted is small, and the current offset package would adequately compensate for impacts to native vegetation provided subsidence related impacts continue to be within the predicted total of 202 ha. Division of Resources and Energy (DRE) noted that the increased subsidence impacts of the modification may affect the final landform and this should be addressed in the extraction, mine closure and rehabilitation strategies. DRE requires the submission of a revised Mining Operations Plan should the modification be approved. Forestry Corporation of NSW (fcNSW) noted NCO is responsible for treating new sources of erosion and repairs to surface cracks, and is liable for costs associated with safety and infrastructure repairs or replacements required as a result of subsidence within State Forest assets. fcNSW noted also that the costs of loss of commercial resources such as timber due to subsidence impacts may also be recoverable under the Mining Act 1992. Australian Rail Track Corporation Ltd (ARTC) was satisfied that transport of up to 11 Mtpa of coal product would be within the currently approved limits for daily rail movements. No comments or recommendations were made by Narrabri Shire Council, Gunnedah Shire Council, Transport for NSW, Roads and Maritime Services or Local Land Services. Full copies of all submissions are included in Appendix D and NCO has considered these submissions in its Response to Submissions (RTS) (Appendix E). 5 ASSESSMENT In assessing the merits of the proposal, the Department has considered: • the modification application and accompanying EA; • the original project EA and conditions of approval for the Narrabri Coal Mine; • previous modifications to the project; • submissions and response to submissions; • relevant environmental planning instruments, policies and guidelines; and • the requirements of the EP&A Act. The Department considers that the key issues related to the modification are subsidence effects and associated impacts to water resources, biodiversity and Aboriginal heritage. 5.1 Subsidence The results of updated subsidence modelling predicts changes of approximately 20% in subsidence effects between the approved and modified mine layout, with some increases and some decreases. Predicted changes to subsidence effects are compared in Table 2 below:

Table 2: Comparison of Predicted Subsidence Impacts from the Approved and Modified Layout

Parameter

Approved Modification LW101-126

(2009 Predictions) LW101-106

(Current Predictions) LW107-120 Final Maximum Subsidence (m) 2.44 2.56 - 2.75 2.75

Maximum Tilt (mm/m)* 30 (45) – 45 (68) 25 (37) – 45 (68) 17 (25) – 41 (62) Maximum Tensile Strain (mm/m)* 4 (8) – 11 (22) 6 (11) – 13 (25) 3 (6) – 11 (21)

Maximum Compressive Strains (mm/m)* 8 (16) – 14 (28) 7 (14) – 16 (32) 4 (8) – 14 (27)

Final Goaf Edge Subsidence (m) 0.22 – 0.59 0.13 – 0.32 0.09 – 0.36

Final Angle of Draw (o) 26.5 - 31 25.3 – 32.2 22.7 – 33.2 * Predicted tilts and strains are for ‘smooth’ subsidence profiles. Cracking or discontinuous displacement may cause an increase of

1.5 to 2 times respectively (bracketed values).


Narrabri Coal Project – Modification 5 Environmental Assessment Report The modelled changes are due to both the proposed change in underground geometry and re-calibration of the original model using measured results from mining of longwalls 101 to 103. As shown in Table 2 above, the re-calibration of the model has increased the predicted subsidence for longwall panels LW101-106. However, the subsidence effects for the wider longwall panels LW107-120 are consistent with the range for the narrower panels of the re-calibrated model. It is also important to note that while some of the subsidence effects are predicted to increase, the effects are not expected to result in significantly higher impacts. Subsidence impacts have already been assessed and approved at the Narrabri Mine, and, with the exception of two privately owned properties, some road easements, and part of Pilliga East State Forest and Jacks Creek State Forest, the land above the extraction area is all owned by NCO. Therefore, any impacts are likely to mostly affect mine-owned infrastructure. Where impacts do occur to infrastructure not owned by the mine, NCO has committed to managing and mitigating impacts by: • repairing damaged structures including dwellings, sheds, roads, fences and dams; • providing temporary water supplies to affected dam owners; • providing signage and traffic control measures for road users during active subsidence; • sheathing power poles in flexible conductor to control conductor tension during/after mining

impacts; and • continuing to conduct mining in accordance with the mine’s Public Safety Management Plan and

individual Extraction Plans.

The Department considers the increased impacts to infrastructure resulting from the proposed modification would be minor, and is satisfied that the ongoing mitigation measures adopted by NCO for impacts to private or state owned property are adequate and consistent with standard practice in the industry. Furthermore, NCO would be required to prepare staged extraction plans for longwall panels LW107-120. This would ensure that predicted impacts are continuously reviewed and appropriate mitigation measures are implemented over the life of the mine. Modelled increases in ponding depths, sub-surface fracturing and surface cracking would also potentially impact the natural environment, with particular consequences for ground and surface water. These are discussed below. 5.2 Groundwater

Potential impacts from the proposed modification would be primarily associated with the incremental increase in subsidence. An increase in sub-surface fracturing and shearing of strata above the underground mine footprint is predicted, with a marginal increase in the area affected due to the 60 m western extension of the underground mine. However, this is offset to some degree by reduction in some of the longwall panel lengths to the north of the mine (see Figure 4). Aquifers overlying the subsidence area are predicted to be affected by direct hydraulic connection to the workings, with an increase in vertical permeability. Groundwater levels would be lowered due to groundwater inflow to the mine workings and increased water storage due to the fracturing of the strata. Peak groundwater inflows under the modified layout are conservatively predicted to be 0.25 ML/day greater than under the approved layout. The change in groundwater inflow compared to the original 28 year mine life is shown in Figure 5. Overall, the total volume to be extracted is predicted to be lower than the estimated total under the current approval due to the shorter mining period. NCO holds sufficient licences to cover the predicted peak water take in all water sources, with the exception of the NSW Murray Darling Basin (MDB) Porous Rock Groundwater Source, where inflows are predicted to exceed NCO’s entitlement in year 11 of the project. Predicted peak water take from this water source is 1,009 ML/year, with 818 ML/year of entitlements currently held by NCO. NCO has committed to monitoring underground mine inflows versus model predictions, and to obtain additional licensed volumes of this water source to account for actual inflows as necessary. DPI Water noted adequate water entitlement was required prior to year 11, and recommended NCO’s commitment and intended timing to acquire additional licences should be included in an updated Water Management


Narrabri Coal Project – Modification 5 Environmental Assessment Report Plan. The Department notes that existing conditions require the Water Management Plan to be updated within three months of a modification to the conditions of approval.

Figure 5: Predicted Groundwater Inflows for the Approved and Modified Mine

During mining operations there would be significant declines in water levels in the immediate vicinity of the mine site, particularly in the north-eastern quadrant. Water level decline in the deeper rock strata (including the target Hoskisson Coal Seam) would also extend beyond the mine site. However, by the cessation of mining, the difference in predicted water levels as a result of the modification would be minor compared to the predicted levels for the approved mine plan. Groundwater drawdown and quality impacts were assessed to comply with the minimum impact considerations under the NSW Aquifer Interference Policy in all water sources except for 2 water supply works within the MDB Porous Rock Groundwater Source. One of these bores is owned by NCO, and the other is a privately owned registered bore (GW067626) located to the north west of the mine in a less productive groundwater source (Purlawaugh formation). This bore was originally predicted to be impacted by a drawdown of up to 5 m, and would now be affected by drawdown of up to 10 m. The Department notes that this bore is currently not included in the approved groundwater monitoring program for the mine site, but has recommended it be included in the revised monitoring program, subject to landowner access arrangements. NCO has committed to implementing an appropriate preventative or remedial strategy in accordance with the ‘make-good’ provisions outlined in the mine’s approved Water Management Plan. This may include potentially deepening or re-equipping the bore, or the provision of alternative water supplies or other agreed compensation if required. DPI Water supports these measures. Groundwater levels are predicted to recover to an equilibrium level about 60-80 years after mining under the modified plan, with 80% recovery within 10-40 years, depending on the monitoring bore location. The model predicts the equilibrium level would be between two and seven metres below pre-mining levels in the shallower layers. DPI Water advised that in its view, groundwater levels should recover to initial levels within 120 years and suggested a discrepancy in the groundwater model that should be rectified in future groundwater modelling. NCO would continue to monitor the groundwater level and quality in accordance with the mine’s Water Management Plan, subject to review as required under the project approval. Any trigger level exceedances or complaints in relation to loss of groundwater supply would be managed in accordance with the mine’s approved Surface and Groundwater Response Plan.


Narrabri Coal Project – Modification 5 Environmental Assessment Report The Department has recommended that provision of a compensatory water supply be included as a condition of the project approval. With this in place, the Department is satisfied that additional impacts to groundwater arising from the proposed modification are not significantly greater than those already approved. 5.3 Surface Water The potential impacts to surface water are related to subsidence impacts at the surface and to management of the mine site water. Impacts Due to Subsidence Continuous sub-surface fracturing can cause direct hydraulic connection between surface waters and the underground workings. Continuous fracturing above the panels was originally predicted to be 50 to 70% of cover depth. Under the modified layout and re-calibration of the modelling, this has been conservatively revised to 78% to 88% of cover depth. This means the fracture zone is predicted to extend to within 21 to 79 m of the surface with cover depths above the coal seam ranging from 165 m to 360m. That is, it is predicted it is unlikely that continuous fracturing will extend into the surface cracking zone. The increase in maximum subsidence from 2.44 to 2.75 m is predicted to increase the depth, volume and area of ponds forming along some of the longwalls and creeks in flatter areas of the site. The maximum pond depth is predicted to increase from 1.5 m to 2.6 m, although it is noted that actual ponding depths would depend on other factors such as rain duration, surface cracking and effective percolation rates. Generally ponding is predicted to occur near existing watercourses and is likely to remain in channel. It is also important to note that approximately 60% of the predicted ponding area over the mine site is associated with subsidence above longwall panels LW101-106, which have either already been mined or will remain at the currently approved longwall panel width. Impacts associated with increased ponding and consequent erosion and sedimentation may include the potential for short term loss of riparian vegetation, the potential for Aboriginal sites to be inundated or disturbed by increased erosion or sedimentation, and increase in the salinity of downstream flows. Major changes in channel morphology are not expected, however smaller channels could drain into major watercourses at alternate locations causing localised bank scour, and sedimentation in ponded areas could change the channel form over time. NCO proposes to continue managing and remediating subsidence impacts on surface waters in accordance with the mine’s Extraction Plan - Water Management Plan. Measures include developing options to protect affected environmental features and prevent saline water discharging downstream if required. Should channel earthworks be required to re-establish drainage pathways, these would be undertaken in accordance with the Land Management Plan. The key consideration is that the predicted impacts are generally consistent with the currently approved impacts and the Department considers that the impacts can be satisfactorily managed under the regime established under the existing conditions, and no further conditions are required. Site Water Management To account for the change in groundwater inflow over the mine life (see Figure 5), the site water balance was reviewed to assess the adequacy of the existing water management system and infrastructure. The water balance model was also re-calibrated to match observed water levels. In particular, the risks associated with uncontrolled releases of saline water or brine due to inadequate storage capacity were assessed. To date, no uncontrolled releases of stored mine water or brine have occurred at the mine, and the modelling predicts the existing water storage facilities would have sufficient capacity, and there is a very low risk (less than 1%) of an uncontrolled release due to the modification. To further minimise the risk of discharge, NCO proposes to install an evaporator spray system on the mine-water storage dam to maintain storage capacity.


Narrabri Coal Project – Modification 5 Environmental Assessment Report The existing approval includes allowance for discharges of treated water to the Namoi River. These controlled discharges are required to comply with criteria outlined in the existing conditions of approval and would also be regulated under the Environment Protection Licence (EPL) issued by the EPA. NCO is also committed to offsetting additional salt loads discharged to the Namoi River, either through capping bores, or through an alternative offset program developed in consultation with DPI Water and OEH. The groundwater inflows predicted at the mine means the demand for water would largely be satisfied by on-site water, particularly when mining the deeper longwall panels to the west. However, based on the water balance modelling, 402 ML of water would need to be sourced from the Namoi River in drier years. NCO currently holds a surface water licence for 678 ML/year to account for this take of water. However, given the risk of insufficient water in the river in dry years, the Department has recommended a condition requiring NCO to ensure it has sufficient water for all stages of the project, and if necessary adjusts the scale of its operations to match the available water. The proposed modification also includes the removal of one sediment dam (SD5) that currently collects water from undisturbed catchments not associated with the mine. Removing the sediment dam would result in 10 ha of undisturbed catchment reporting back to Kurrajong Creek. The Department is satisfied that the additional surface water impacts resulting from the modification would be generally consistent with the approved impacts and that no adverse impacts to water quality are predicted from the proposed modification. 5.4 Biodiversity No additional direct clearing of native vegetation would be required for the proposed modification beyond that already approved. However, indirect impacts to native vegetation may occur due to subsidence. The proposed change in the configuration of the longwall panels includes shortening the northern end of longwall panels LW104 to LW108 (where the geology renders mining unviable) and extending the panels 60 m to the west. This would mean approximately 8 ha of native vegetation (~7 ha of Inland Grey Box Woodland and ~1 ha of Riparian Forest) along the northern boundary of the underground mining footprint would no longer fall within the predicted subsidence zone. However, an additional 17 ha of native vegetation comprising Brown Bloodwood/Pilliga Box Woodland lies above the proposed western extension of the underground footprint. Consequently a total of 9 ha of additional vegetation would potentially be impacted indirectly by subsidence. This represents a very small increase (approximately 0.5 %) in the area of native vegetation within the mine footprint. The majority of native vegetation, including parts of the Pilliga East State Forest, is located above the western extent of the underground footprint. Subsidence impacts are predicted to decline towards the west as the coal seam dips down in that direction and the depth of cover increases to approximately 360m. Consequently, minimal impacts to the additional native vegetation or the Pilliga East State Forest are expected. Should subsidence impacts occur within state forests, NCO acknowledges responsibility for any costs associated with safety and infrastructure repair or commercial losses resulting from mining induced subsidence. No significant additional impacts on listed threatened flora, fauna or ecological communities are anticipated from the modification as material changes such as cracking, land stability, reduction in soil moisture, soil erosion, and deviation of surface flows resulting directly from the modification would be minor. NCO would continue to undertake subsidence impact mitigation and remediation measures for the modification and a biodiversity offset area to compensate for the direct impacts from native vegetation clearing, and indirect impacts associated with subsidence has already been approved. OEH advised the Department that the current offset package would adequately compensate for the additional 9 ha of potentially affected vegetation. The Department is satisfied that the existing mitigation and monitoring requirements of the Extraction Plan, Biodiversity Management Plan and the Biodiversity Offset Package adequately account for the impacts to biodiversity that would result from the modification.


Narrabri Coal Project – Modification 5 Environmental Assessment Report 5.5 Aboriginal Heritage A targeted survey conducted by Niche Environment and Heritage and attended by representatives from the Registered Aboriginal Parties found no Aboriginal heritage sites or areas of Aboriginal cultural heritage value in the area associated with the western extension of the underground mine footprint. There are also no previously recorded Aboriginal heritage sites located within this area. Unidentified items of Aboriginal cultural heritage that may be located within the area would be avoided through adherence to the protocols outlined in the mine’s Aboriginal Cultural Heritage Management Plan. Consequently, no additional impacts on known Aboriginal cultural heritage values are predicted due to the underground extension. One hundred and forty one (141) Aboriginal heritage sites have been previously identified in and around the mine site with 66 of these located at or near areas subject to predicted subsidence and surface cracking associated with the approved longwall layout. These were all previously assessed as being of low archaeological significance. Direct impacts to these sites as a result of subsidence are considered unlikely, although loss, damage or burial due to surface cracking, or increased erosion or sedimentation resulting from subsidence or subsidence remediation in the vicinity of the sites is possible. The incremental potential impacts as a result of the modification are considered relatively minor, although the increase in ponding due to increased subsidence may also affect some artefact scatters or isolated finds. NCO would continue to implement the management and mitigation measures outlined in the mine’s Aboriginal Cultural Heritage Management Plan, Heritage Management Plan and Land Management Plan. The Department considers that on the basis of the above, significant additional impacts as a result of the modification are unlikely, and where impacts do occur they can be appropriately managed through the existing conditions of approval, in consultation with Aboriginal stakeholders. 5.6 Other Issues A summary of the Department’s assessment of all other relevant issues is provided in Table 3 below. Table 3: Assessment of Other Issues

Issue Impact and Consideration Recommendation Noise • No additional plant or infrastructure would be required for the increase in

production. However, the peak capacity of existing plant and infrastructure would be reached more often.

• Consequently, operational noise levels assessed on a 15 minute basis would not change, but potentially typical worst case predicted noise levels could occur more often as the combination of plant operating at full capacity and noise enhancing meteorological conditions is more likely to occur.

• The increase to the average number of train movements from 3 to 4 is expected to increase noise by approximately 1 dB(A) for both daytime and night time. However, the resulting noise levels along the public rail network are modelled to be below the noise trigger levels identified in the Rail Infrastructure Noise Guideline.

• A small increase in heavy vehicle deliveries is proposed as part of the modification. Noise impacts associated with these additional vehicle movements would be negligible and within the 2 dB increase outlined in the NSW Road Noise Policy guideline.

• The evaporators proposed to be adopted for the modified mine would operate during the daytime only and would be selected and located to minimise potential noise impacts.

• The EPA raised concerns about recent noise level exceedances at neighbouring properties.

• NCO is considering a written request to purchase one of the properties, and proposes to implement noise monitoring at (or near) the second property (Oakleigh), and install a temperature inversion tower at the mine site to provide continuous noise and temperature inversion data to the CHPP control room, which is operated 24 hours per day.

• A Trigger Action Response Plan would be developed, with possible mitigation measures that include: - modification of CHPP activities; - re-deployment or standing down of stockpile dozers; and/or

No additional conditions or amendments are necessary.



6 RECOMMENDED CONDITIONS

The Department has drafted a notice of modification for the proposed modification (see Appendix A) and a consolidated version of the Project Approval as modified (see Appendix B). The Department has recommended the project approval be amended to increase the ROM coal extraction limit to 11Mtpa. The Department has also recommended conditions requiring NCO to: • provide a compensatory water supply for landowners whose water supply is adversely affected;

and • ensure they have adequate water supply for the project, or adjust the scale of operations to match

the available water. Finally, the Department has recommended some minor administrative changes to the conditions, including updates to the definitions and site layout figures. 7 CONCLUSION The Department has assessed the merits of the modification in accordance with the relevant requirements of the EP&A Act. Based on this assessment the Department considers that the proposed modification is reasonable and would allow NCO to improve the operational efficiency of the mine. The increase in processing rate would not require additional infrastructure and therefore amenity impacts are minor. The incremental subsidence effects and associated impacts would be relatively minor and can be effectively managed under the existing conditions of approval, including revisions to the relevant management plans.

- implementation of first gear reverse on stockpile dozers to reduce dozer track noise.

• The EPA supports the proposal and considers the existing noise conditions are appropriate for regulating noise.

• The Department is satisfied that the existing noise conditions are adequate. However, the measures proposed above would reduce the potential for noise criteria exceedances and should be included in the mine’s Noise Management Plan, which is required to be updated in accordance with existing conditions.

Air Quality

• The mine has generally operated within air quality limits since 2007, with the exception of a cumulative 24-hour PM10 exceedance associated with short-term construction activities in 2008 and an exceedance in 2009 due to a regional dust storm event.

• Additional air quality modelling was undertaken to account for the proposed increase in production. The results of this modelling indicate that the modification would not result in any exceedance of air quality criteria.

• The EPA raised no issues in relation to air quality, and air quality impacts are already controlled under strict conditions of approval.

• Consequently, the Department is satisfied that NCO’s continued compliance with existing dust criteria, and efforts to minimise greenhouse gas emissions in accordance with its Greenhouse Gas Minimisation Plan and its Energy Savings Action Plan are adequate.

No additional conditions or amendments are necessary.

Traffic

• A minor increase in heavy vehicle movements would be required due to the increased demand for consumables associated with the increased ROM coal production rate.

• It is estimated that heavy vehicles movement would increase by an average of 4 movements per day, with a peak of 10 movements per day. This would represent a 0.2 % and 0.5 % increase in existing Kamilaroi Highway movements respectively.

• The Department is satisfied that the increase in vehicle movements would be within the range of daily traffic variations and would not result in significant impacts to the road network or road safety.

No additional conditions or amendments necessary.

Other Issues

• Other issues associated with the proposed modification are considered to be minor issues, components of key issues, or of minor environmental impact, and can be adequately managed via the existing conditions of approval.

No additional conditions or amendments necessary.



APPENDIX A: NOTICE OF MODIFICATION



APPENDIX B: CONSOLIDATED PROJECT APPROVAL



APPENDIX C: ENVIRONMENTAL ASSESSMENT

See website at: http://majorprojects.planning.nsw.gov.au/index.pl?action=view_job&job_id=7294


http://majorprojects.planning.nsw.gov.au/index.pl?action=view_job&job_id=7294


APPENDIX D: SUBMISSIONS





APPENDIX E: RESPONSE TO SUBMISSIONS




narrabri coal mine – modification change to underground

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