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Application for Works Approval
Division 3, Part V Environmental Protection Act 1986
Works Approval Number
W6355/2020/1
Applicant Karara Mining Limited
ACN 070 871 831
File Number DER2020/000041
Premises
Karara Minesite /Blue Hills North Minesite
M59/721, M59/644, M59/645, G59/38, L59/99 and L59/109 PERENJORI WA 6620
Date of Report 26 March 2020 Status of Report Final
Decision Report
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1. Definitions of terms and acronyms
In this Decision Report, the terms in Table 1 have the meanings defined.
Table 1: Definitions
Term Definition
ACN Australian Company Number
Applicant Karara Mining Limited BHN pit Blue Hills North pit Category/
Categories/ Cat.
Categories of Prescribed Premises as set out in Schedule 1 of the EP Regulations
Decision Report refers to this document.
Delegated Officer an officer under section 20 of the EP Act.
Department means the department established under section 35 of the Public Sector Management Act 1994 and designated as responsible for the administration of Part V, Division 3 of the EP Act.
DMIRS Department of Mines, Industry Regulation and Safety DWER Department of Water and Environmental Regulation
As of 1 July 2017, the Department of Environment Regulation (DER), the Office of the Environmental Protection Authority (OEPA) and the Department of Water (DoW) amalgamated to form the Department of Water and Environmental Regulation (DWER).
DWER was established under section 35 of the Public Sector Management Act 1994 and is responsible for the administration of the Environmental Protection Act 1986 along with other legislation.
EP Act Environmental Protection Act 1986 (WA)
EP Regulations Environmental Protection Regulations 1987 (WA)
EPBC Act Environment Protection and Biodiversity Conservation Act 1999 (Cth)
Existing Licence The Licence issued under Part V, Division 3 of the EP Act and in force prior to the commencement of, and during this assessment.
GDE Groundwater Dependent Ecosystem
km kilometre
KML Karara Mining Limited
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m metre
mbgl metres below ground level mg/L milligram per litre
MS Ministerial Statement
Occupier has the same meaning given to that term under the EP Act.
Prescribed Premises
has the same meaning given to that term under the EP Act.
Premises refers to the premises to which this Decision Report applies, as specified at the front of this Decision Report
PEC Priority Ecological Community
Risk Event As described in Guidance Statement: Risk Assessment RIWI Act Rights in Water and Irrigation Act 1914 (WA)
TDS Total Dissolved Solids
UDR Environmental Protection (Unauthorised Discharges) Regulations 2004 (WA)
Works Approval Holder
Karara Mining Limited
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2. Purpose and scope of assessment
2.1 Application details
Karara Mining Limited (KML) (Applicant) (Works Approval Holder) submitted an application with supporting documents (Application) on 16 January 2020 to the Department of Water and
Environmental Regulation (DWER) for a works approval under the Environmental Protection Act 1986 (EP Act).
The application is for extraction of up to 573,600 tonnes of water per year from the Karara pit to allow mining of ore, with discharge to the now disused Blue Hills North pit.
The premises is defined by tenements M59/721, M59/644, M59/645, G59/38, L59/99 and L59/109, in the Shire of Perenjori, Western Australia. All the tenements are held by Karara Mining Limited.
Table 2 lists the prescribed premises category that has been applied for.
Table 2: Prescribed Premises Category Classification
of Premises
Description Assessed Production
Category 6
Mine dewatering: premises on which water is extracted and discharged into the environment to allow mining of ore.
573,600 tonnes per year
2.2 Scope of Assessment
This Decision Report assesses emissions and discharges associated with construction of the works and time limited operations of the proposed category 6 dewatering.
This assessment has resulted in the Department of Water and Environmental Regulation issuing works approval W6355/2020/1 which is contained in Attachment 1.
2.3 Background - licence
KML currently holds licence L8721/2013/1 for the prescribed premises categories listed in Table 3.
Table 3: Existing licence L8721/2013/1
Prescribed Premises Category
Description Approved premises production or design
capacity or throughput
05 Processing or beneficiation of metallic or non-metallic ore
Not more than 30,000,000 tonnes per year
54 Sewage facility 540 cubic metres per day
64 Class II putrescible landfill site Not more than 5,000 tonnes per year The existing L8721/2013/1 premises is defined by the boundaries of M59/644, M59/645, G59/38, L59/99 and L59/109 and includes the Karara Pit, but not the Blue Hills North pit, as shown below in Figure 1.
For ongoing operation of the proposed dewatering to Blue Hills North pit, an amendment to the licence will be required for addition of category 6, and the premises boundary expanded to include M59/721.
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Figure 1: Premises boundary
3. Overview of the proposal
Since commencement of mining, dewatering from the Karara pit has been used for dust suppression and ore processing. However due to variability of volumes that may be
encountered as mining progresses, KML requires a contingency measure to enable disposal of water in excess of that required for re-use.
KML proposes to discharge the excess dewatering into the dis-used Blue Hills North (BHN) pit. It is expected that the water will be later recovered during summer for re-use by dust suppression and processing.
3.1 Works
Water is currently transferred to the Karara Mine Site from local bores, Blue Hills North pit and Terapod pit to supplement the water supply required for the ongoing Karara site operations.
The water transfer pipeline is situated on an existing haul road, which is windrowed to contain spills.
Discharge of dewatering from Karara pit to Blue Hills North pit will involve the reversal of flow through the existing pipeline network. Figure 2 shows the pipeline route.
Only minor construction activities will be undertaken, consisting of reversing pump flows and some minor work to improve windrows for containment of spills.
No additional clearing of native vegetation is required. If clearing is required, it will be minimal for maintenance purposes or to strengthen secondary existing containment measures and will be within existing approved disturbance areas only.
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3.2 Operations
Saline water, currently between 35,000 and 40,000 milligram/litre (mg/L) Total Dissolved Solis (TDS) from the Karara pit will be discharged into the BHN pit, which in December 2019,
recorded 71,400 mg/L TDS.
Discharge to Blue Hills North (BHN) pit will only occur when surplus water from Karara pit is unable to be used for dust suppression and ore processing. Dewater will be discharged to a maximum height of 345 m AHD which allows a freeboard of 35 m to the pit crest.
To prevent and or mitigate unplanned spills of saline de-water to the environment KML proposes:
Daily inspections of the length of the pipeline to detect leaks when the pipeline is in operation. If a leak is identified and it is determined that it could have an impact on surrounding vegetation then pumping will be ceased, the pipeline will be isolated and repairs will be made as soon as practicable.
Above ground pipelines windrowed to contain rupture and leaks.
Pipelines buried at track crossings to minimise risk of vehicles driving over pipelines.
Flow meter installed to quantify volumes.
Discharge pipe sited to minimise blowback.
Discharge pipe far enough over the pit crest or down the pit ramp to reduce exposure to wind.
Discharge pipe sited away from remnant vegetation.
Daily confirmatory inspections of the discharge point when discharging.
If blowback observed, discharge point modified or moved to mitigate impact to vegetation.
Diesel for power requirements will be supplied through a mobile fuel truck from the existing approved onsite bulk fuel storage facility. No additional fuel storage is proposed. Spills will be contained and managed by absorbent material and excavation.
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Figure 2: Site Plan
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3.3 Infrastructure
The infrastructure, as it relates to the proposed Category 6 activity, is detailed in Table 4 and with reference to the site plan (Figure 2).
Table 4: Category 6 infrastructure
Infrastructure Site Plan Reference
Prescribed Activity Category 6
Dewater from Karara pit will be discharged via existing pipeline infrastructure into Blue Hills North pit.
1 Dewater pipeline from KML pit to Saline Water Pump Station - situated on an existing haul road and within windrows.
Figure 2 Site Plan 2 Saline Water Pump Station
3 Dewater pipeline from Saline Water Pump Station to Blue Hills North pit - situated on existing haul road and within windrows.
4 Flow meter N/A
4. Location and siting
4.1 Siting context
The premises is located in the Mid-West region of Western Australia and is approximately 65 kilometres (km) north-east of Perenjori.
4.2 Residential and sensitive receptors
The distance to the closest sensitive land use is Karara Homestead, which is located approximately 7 km southwest of the beneficiation plant and 15 km from the BHN pit.
Due to the distance from potential emissions to the receptor during construction and operation for the dewatering, the homestead is not considered a sensitive receptor for this assessment.
4.3 Specified ecosystems
Blue Hills Priority Ecological Community and Threatened/Priority Flora
The Priority 1 Ecological Community (PRC) Mid West 2 Mt Karara/Mungada Ridge (Blue Hills) Banded Ironstone Formation (BIF) is located within the proposed area of activity (Figure 3).
There are no known groundwater-dependent vegetation communities on the BIF ridges, nor are there likely to be due to the significant depth to natural groundwater. There are several priority species occurring across the BIF range; however none of these species are
considered to be groundwater dependent (Application). Rockwater (2019) concluded the pit lake level could be raised to 345 m AHD (35 m below pit crest) without groundwater levels beneath the flanks of the BIF ridge being closer than 20 metres below ground level (mbgl), the maximum likely rooting depth of most vegetation in the area.
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It is possible that eucalypt trees have a rooting zone greater than 20 m. However, according to Rockwater (2019), pre-mining hydrogeological conditions in the vicinity of the trees indicate an initial depth to water of 20-30 m, which is higher than the proposed pit lake level limit.
Advice to Rockwater (2019) for estimates of rooting depth for species and communities was provided by Dr Adam Cross, Research Fellow at the ARC Centre for Mine Site Restoration, Curtin University as summarised below. Dr Cross noted that “these are informed estimates, based upon what I can find in the literature and from our personal experience, and may not be entirely accurate. Noting that arid regions are recognised as harbouring species with deeper- than-average rooting depths in order to facilitate drought survival, the estimates below represent the upper end of expected rooting depths for these life forms from published works but may still underestimate true rooting depth.”
Vegetation associations
The estimated maximum rooting depths of vegetation associations immediately surrounding Blue Hills North pit is that:
many of the larger shrubs and trees may exhibit rooting depths in excess of 20 m based upon data available for similar species in comparable bioregions; however
it would be unlikely that any would possess roots to 40 m, other than the largest Eucalyptus individuals in vegetation association 7 (Figure 3) that may possess roots to 40 m.
Priority Flora
Estimates of expected rooting depths of priority flora immediately surrounding Blue Hills North pit are shown in Table5.
Table 5: Priority flora species immediately surrounding Blue Hills North pit
Priority Species Estimated maximum Rooting
P1 Acacia karina 5-20 m
P1 Lepidosperma sp. Blue Hills
1-10 m
P3 Grevillea globosa 2-10 m
P3 Drummondita fulva 2-10 m
P3 Melaleuca barlowii 5-20 m
P3 Micromyrtus acuta 2-10 m
P3 Micromyrtus trudgenii 2-10 m
P3 Persoonia pentasticha 2-10 m
P3 Rhodanthe collina <1 m
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Figure 3: Blue Hills PEC and vegetation associations
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Potential groundwater dependent vegetation
There could possibly be trees dependent on shallow groundwater in the non perennial lake shown in Figure 4 below shaded in blue, near bore YGW011 and 2.5 km northwest of BHN pit.
Low permeability of rocks bounding the BIFs restricts lateral groundwater flows and hydraulic head changes, and Rockwater (2019) concluded it unlikely there would be impacts to the vegetation.
A topographic depression marked as having calcrete to the east of the pit (shaded in green Figure 4) was the subject of a GDE study in 2009 which concluded that the Eucalypt of the area was not groundwater dependent as the rooting depth was up to about 8.6 m, whereas the groundwater occurred at depths >25 m. In a subsequent site inspection, no calcrete was found in that area by a Rockwater hydrogeologist (Rockwater, 2019).
Figure 4: Potential groundwater dependent vegetation
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Threatened/Priority Fauna
Baseline studies show no stygofauna in the vicinity of the pit.
Parks and Wildlife Managed Lands
The Karara Pastoral Lease was acquired by the then Department of Environment and Conservation for conservation purposes. Possible reservation would be as a Conservation Park.
Groundwater and water sources
The distances to groundwater and water sources are shown in Table 6.
Table 6: Groundwater and water sources Groundwater and
water sources
Distance from the activity
Environmental value
Non-perennial lake 2.5 km from BNH pit Vegetation Groundwater - salinity
is variable (see section 5).
Depth to groundwater varies with topography (see Section 5).
Originally, wells produced water for stock use.
The Karara station has now been de-stocked for environmental reasons, and the wells abandoned.
There are currently no groundwater users nearby except Karara Mining. Future uses in the long term are unknown.
Gascoyne
Groundwater Area
Premises located within the Area
Rights in Water and Irrigation Act 1914 (WA) (RIWI Act) proclaimed area
5. Hydrogeology
Aquifers around the area mainly comprise fractured Banded Iron Formation (BIF), particularly where the BIF is intersected by cross-cutting features such as faults.
Water table at the project area is related to ground elevation and ranges from 5.8 m to 80 meters below ground level (mbgl) (Application 7.3).
Pre-mining groundwater levels in 2008 indicate a static groundwater level of about 335 m AHD at the BHN pit (Rockwater, 2019)
Groundwater is generally fresh to brackish near the water table, and is highly saline below depths of 50 m to 100 m but is variable between bores (Application 7.3).
Bore MKW311 just south of BHN pit is saline or hypersaline from the water table down and produces saline water up to 84,000 mg/L Total Dissolved Solids (TDS). Bores in the vicinity of the pit have shown frequent salinity peaks. Bore MKW311, just south of BHN pit, produces highly saline water when pumped – up to 84,000 mg/L TDS. However Mungamia Well located 3.5 km to the north-east has a salinity of around 16,700 mg/L TDS. (Application section 7.3).
Abstraction of groundwater at the Karara Mine Site project area is authorised under the RIWI Act by GWL171229. DWER’s Water section was referred the works approval application and in summary, commented that:
To date there has been little dewatering of Karara pit and no water quality data is reported. The area has numerous production bores and generally these have started out brackish but become saline in response to abstraction. It could be expected that the Karara pit will respond in the same way.
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Data is available from monitoring bores located at either end of the BHN pit. BHN1003 is also close to production bore MKC439 so it will be influenced by abstraction from this bore. The Rockwater (2019) report supplied as supporting information has graphed TDS for these bores; see Figure 5 below.
The BHN pit is situated on a ridge, see Figure 6. With drainage from the pit likely to move in a west-north-westerly direction towards a localised low evaporation basin.
This will likely not to have impact on groundwater chemistry or quality.
KML report regularly to the Department that they have difficulty to find enough water at site for operational purposes. It is therefore expected that KML would end up using most of the dewater stored at BHN pit eventually for operational use.
Figure 5: Salinity for bores at Blue Hills North pit
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Figure 6: Blue Hills North Pit topography
6. Water disposal to Blue Hills North pit
A cross-section through the pit is shown in Figure 7 below.
Figure 7: Cross section through Blue Hills North pit – surface water levels.
The pre-mining groundwater level was at 336.5 m AHD (blue solid line Figure 7). Current water level (December 2019) is shown by the dotted red line. Proposed limit of discharge level RL 345 m of discharge is shown by the dotted blue line.
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Groundwater levels are expected to rise to near pre-mining levels within a few hundred metres to the south-east and north-west (across-strike) of the pit.
Once all mining ceases at Karara, BHN pit will become a permanent groundwater sink, and groundwater (including residual saline water originating from Karara pit) will gradually flow back to BHN pit and the pit lake level will stabilise where rainfall plus groundwater inflows to the pit balance evaporative losses. That level was estimated by Advisian (2019) by numerical modelling to be at 329 m AHD and by Rockwater using the reported dewatering flow rates and a pit water balance, at about 325 m AHD (Rockwater, 2019).
7. Monitoring
KML currently monitors bores within the vicinity of Blue Hills North pit (BHN1003, BHN1002 and MKC439) (Figure 2) monthly for Standing Water Level, pH, Electrical Conductivity (EC), and Total Dissolved Solids (TDS). A full chemical analysis of these bores is conducted annually (June). KML proposes to maintain this level of monitoring throughout dewatering operations.
8. Legislative context 8.1 Part V of the EP Act
Applicable regulations, standards and guidelines
The overarching legislative framework of this assessment is the EP Act and EP Regulations.
The guidance statements which inform this assessment are:
Guidance Statement: Setting Conditions (October 2015)
Guidance Statement: Environmental Siting (November 2016)
Guidance Statement: Risk Assessment (February 2017)
Guidance Statement: Decision Making (June 2019)
Guideline: Industry Regulation Guide to Licensing (June 2019)
Clearing
Discharge lines are located within the approved development footprints of Ministerial Statement Number (MS) 805 and MS 806. Existing infrastructure will be used for the
dewatering. Any clearing required for maintenance or improving spill containment will be within the MS approved areas.
8.2 Other approvals
Table 7 summarises other approvals relevant to the assessment.
Table 7: Relevant approvals
Legislation Number Approval
Mining Act 1978 (WA) Reg ID 84848 Submitted 16th January 2020, still pending approval Mining Proposal 16th January 2020 to the Department of Mines, Industry Regulation and Safety, pending approval at the time of this assessment.
Environment Protection and Biodiversity
EPBC 2006/3017 Approved 30th March 2010 for the Karara Iron Ore Project. The approval permits “construction and
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Legislation Number Approval
Conservation Act 1999 (Cth)
operation a magnetite iron ore mine, processing plant and associated infrastructure, as described in the Public Environmental Review, dated September 2008”
Rights in Water and Irrigation Act 1914 (WA) (RIWI Act)
GWL171229 Extraction of water from Karara pit is permitted for processing and dust suppression.
Part IV of the EP Act MS 805 Karara Iron Ore Project. Dewatering activities are permitted.
Condition 7-1 requires that “the proponent shall ensure that groundwater abstraction does not adversely affect the groundwater regime which supports vegetation on the gilgai formation” and conditions 7.2 to 7.5 require groundwater level monitoring within and near with trigger levels for action, and monitoring of the health and vegetation of the vegetation.
Table 1: Summary of key proposal characteristics includes “the groundwater table is predicted to be intersected by the pit in year 3 which would require pit dewatering of approx 600 kL/d:
• Increasing to approx 1,300 kL/d in year 16; and
• Decreasing to approx 830 kL/d in year 23.”
MS 806 Mungada Iron Ore Project (encompassing Blue Hills North and Terapod pits).
9. Consultation
The Application was advertised for 7 days for public consultation. No submissions were received.
The Application was referred to the Department of Mines, Industry Regulation and Safety (DMIRS) for comment. DMIRS had no objections.
The Application was also referred to DWER’s Water section for comment (as discussed in Section 5).
10. Risk assessment
Emissions during construction and operation have been assessed separately. Risk ratings have been assessed for each key emission source and take into account potential source- pathway-receptor linkages.
Consequence ratings, likelihood ratings and risk descriptions are detailed in the Department’s Guidance Statement: Risk Assessments (February 2017) and Section 10.3 of this Decision Report. The mitigation measures / controls proposed by the Applicant have been considered in determining the risk rating and regulatory controls, (Guidance Statement: Risk
Assessments, February 2017).
The works approval that accompanies this report authorises construction and operations under a time limited operations phase only. A licence with is required for ongoing operation of the premises.
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10.1 Risk assessment – construction
Risk Event - Source/Activities Potential emissions
Potential receptors, pathway and impact
Applicant controls Consequence Likelihood Risk Reasoning Regulatory controls
Category 6:
Mine dewatering
Strengthening and maintenance work on secondary containment (windrows)
Dust Air/windborne
pathway causing impacts to vegetation of Blue Hills PEC
Information not provided
Slight Rare Low The minor and short term construction
works are not expected to generate significant dust emissions.
N/A
The general provisions of the EP Act apply.
Diesel spill from vehicles
Direct discharge with soil contamination
Refueling by mobile truck, no additional fuel storage required.
Spills managed by absorbent material and excavation.
Slight Unlikely Low Construction works are short term and relatively small scale.
The Environmental Protection (Unauthorised Discharges) Regulations 2004 (WA) apply.
10.2 Risk assessment – operation
Risk Event -
Source/Activities Potential emissions Potential receptors,
pathway and impact Applicant controls Consequence Likelihood Risk Reasoning Regulatory controls
Category 6:
Mine dewatering
Transfer of water from Karara pit to BHN pit.
Pipeline burst or leaks – saline water
Blue Hills PEC.
Priority flora species and vegetation associations.
Direct discharge of saline water with loss of vegetation.
Pipeline route along a cleared road.
Above ground pipelines windowed to enable containment of spill between inspections.
Pipelines buried at track crossings.
Daily inspections to detect leaks and spills when pipeline is in operation.
Moderate Unlikely Medium Priority flora and vegetation complexes are potential receptors of a saline spill.
Applicant’s controls - inspections and containment of spill.
Applicant’s controls will be conditioned as construction and time limited operation requirements.
Construction requirement for installation of flow meter to enable monitoring of dewater discharge.
Discharge of dewater into BHN pit.
Blow back of saline water at the discharge point
Blue Hills PEC.
Priority flora species and vegetation associations.
Loss of vegetation due to saline spray/misting.
Discharge pipe sited to minimise blowback.
Discharge pipe far enough over the pit crest or down the pit ramp to reduce exposure to wind.
Discharge pipe sited away from remnant vegetation.
Daily inspections of the discharge point when discharging.
If blowback observed, discharge point modified or moved to mitigate impact to vegetation.
Moderate Unlikely Medium Priority flora and PEC vegetation are potential receptors of saline spray.
Applicant’s controls – siting of discharge point and inspections.
Applicant’s controls will be conditioned as construction and time limited operation requirements.
Discharge of dewater into BHN pit.
Saline water mounding Saline water rising into root zones with potential for loss of vegetation:
Blue Hills PEC, Priority flora species
Discharge of dewater to BHN pit limited to 345 mAHD (35 m below pit crest).
Moderate Unlikely Medium No priority flora species in the vicinity of the BHN pit are considered likely to root beyond 20 mbgl.
None of the species in the vegetation associations adjacent to the BHN pit are considered to have roots more than
Time limited operations conditions for dewater limit to 345 mAHD and monthly monitoring of pit water level to confirm compliance with the limit.
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Risk Event -
Source/Activities Potential emissions Potential receptors,
pathway and impact Applicant controls Consequence Likelihood Risk Reasoning Regulatory controls
and vegetation association on the flanks of the pit, and groundwater
dependent vegetation
~ 2.5 km from BHN pit.
20 m deep, apart from the Eucalyptus in vegetation association 7 which is considered possible to harbour roots to 40 m.
Low permeability of rocks bounding the BIFs restricts lateral groundwater flows and hydraulic head changes
(Rockwater, 2019).
Anticipated re-use of pit water.
Applicant controls – dewater limit to 345 mAHD (refer to Sections 5 and 6).
Time limited operations conditions for monthly monitoring of groundwater bores SWL levels
(mounding) and salinity.
Discharge of dewater into BHN pit
Saline dewater Salinisation of aquifer due to dewater from Karara Mine pit.
Anticipated re-use of BHN pit water.
Slight Unlikely Low December 2019, recorded BHN pit water 71,400 mg/L TDS.
Anticipated re-use of pit water.
Drainage from the pit likely to move in a west-north-westerly direction and will likely not to have impact on
groundwater chemistry or quality.
Long term the pit is expected to act as a groundwater sink.
Risk Event is acceptable and will not be subject to regulatory controls.
Refueling and operation of pumping infrastructure
Hydrocarbons spillage Direct discharge with soil contamination
Refueling by mobile truck.
No additional fuel storage required.
Spills managed by absorbent material and excavation.
Slight Unlikely Low Applicant’s controls. The Environmental
Protection (Unauthorised Discharges) Regulations 2004 (WA) apply.
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10.3 Consequence and likelihood of risk events
A risk rating will be determined for risk events in accordance with the risk rating matrix set out in Table 8 below.
Table 8: Risk rating matrix Likelihood Consequence
Slight Minor Moderate Major Severe
Almost certain Medium High High Extreme Extreme
Likely Medium Medium High High Extreme
Possible Low Medium Medium High Extreme
Unlikely Low Medium Medium Medium High
Rare Low Low Medium Medium High
DWER will undertake an assessment of the consequence and likelihood of the Risk Event in accordance with Table 9 below.
Table 9: Risk criteria table
Likelihood Consequence
The following criteria has been used to determine the likelihood of the Risk Event occurring.
The following criteria has been used to determine the consequences of a Risk Event occurring:
Environment Public health* and amenity (such as air
and water quality, noise, and odour)
Almost Certain
The risk event is expected to occur in most circumstances
Severe onsite impacts: catastrophic
offsite impacts local scale: high level or above
offsite impacts wider scale: mid-level or above
Mid to long-term or permanent impact to an area of high conservation value or special significance^
Specific Consequence Criteria (for environment) are significantly exceeded
Loss of life
Adverse health effects: high level or ongoing medical treatment
Specific Consequence Criteria (for public health) are significantly exceeded
Local scale impacts: permanent loss of amenity
Likely The risk event will probably occur in most circumstances
Major onsite impacts: high level
offsite impacts local scale: mid-level
offsite impacts wider scale: low level
Short-term impact to an area of high conservation value or special significance^
Specific Consequence Criteria (for environment) are exceeded
Adverse health effects: mid-level or frequent medical treatment
Specific Consequence Criteria (for public health) are exceeded
Local scale impacts: high level impact to amenity
Possible The risk event could occur at some time
Moderate onsite impacts: mid-level
offsite impacts local scale: low level
offsite impacts wider scale: minimal
Specific Consequence Criteria (for environment) are at risk of not being met
Adverse health effects: low level or occasional medical treatment
Specific Consequence Criteria (for public health) are at risk of not being met
Local scale impacts: mid-level impact to amenity
Unlikely The risk event will probably not occur in most
circumstances
Minor onsite impacts: low level
offsite impacts local scale: minimal
offsite impacts wider scale: not detectable
Specific Consequence Criteria (for environment) likely to be met
Specific Consequence Criteria (for public health) are likely to be met
Local scale impacts: low level impact to amenity
Rare The risk event may only occur in exceptional circumstances
Slight onsite impact: minimal
Specific Consequence Criteria (for environment) met
Local scale: minimal to amenity
Specific Consequence Criteria (for public health) met
^ Determination of areas of high conservation value or special significance should be informed by the Guidance Statement:
Environmental Siting.
* In applying public health criteria, DWER may have regard to the Department of Health’s Health Risk Assessment (Scoping) Guidelines. “onsite” means within the Prescribed Premises boundary.
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10.4 Acceptability and treatment of Risk Event
DWER will determine the acceptability and treatment of Risk Events in accordance with the Risk treatment table 10 below:
Table 10: Risk treatment table Rating of Risk
Event
Acceptability Treatment
Extreme Unacceptable. Risk Event will not be tolerated. DWER may refuse application.
High May be acceptable.
Subject to multiple regulatory controls.
Risk Event may be tolerated and may be subject to multiple regulatory controls. This may include both outcome-based and management conditions.
Medium Acceptable, generally subject to regulatory controls.
Risk Event is tolerable and is likely to be subject to some regulatory controls. A preference for outcome-based conditions where practical and appropriate will be applied.
Low Acceptable, generally not controlled.
Risk Event is acceptable and will generally not be subject to regulatory controls.
11. Applicant’s comments
The Applicant was provided with the draft Decision Report and draft Works Approval on 20 March 2020 for comment. The Applicant responded requesting the comment period be waived and stated that Conclusion
The Applicant requested the comment period be waived and provided comment which, along with DWER’s response, is listed in Appendix 2.
12. Conclusion
This assessment of the risks of activities on the premises has been undertaken with due consideration of a number of factors, including the documents and policies specified in this decision report (summarised in Appendix 1).
DWER notes that it may review the appropriateness and adequacy of controls at any time and that, following a review, DWER may initiate amendments to the approval under the EP Act.
Alana Kidd
Manager, Resource Industries Delegated Officer
under section 20 of the Environmental Protection Act 1986
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Appendix 1: Key documents
Document title In text ref Availability
Works Approval W6355/2020/1 application form and supporting documentation
Application DWER records (A1861344, A1865521, A1876396)
Ministerial Statement 805 MS 805
accessed at www.epa.wa.gov.au/
Ministerial Statement 806 MS 806
DER, July 2015. Guidance Statement: Regulatory principles. Department of Environment
Regulation, Perth.
accessed at www.dwer.wa.gov.au/
DER, October 2015. Guidance Statement: Setting conditions. Department of Environment
Regulation, Perth.
DER, November 2016. Environmental Siting.
Department of Environment Regulation, Perth.
DER, February 2017. Guidance Statement: Risk Assessments. Department of Environment Regulation, Perth.
DWER, June 2019. Guideline: Decision Making.
Department of Water and Environmental Regulation, Perth.
DWER, June 2019. Guideline: Industry Regulation Guide to Licensing. Department of Water and Environmental Regulation, Perth.
Rockwater Hydrogeological and Environmental Consultants, December 2019. Impacts of Disposing Water to Blue Hills North Pit. Report No. 319.6/19/01
Rockwater, 2019
Appendix 1 of Application
supporting documentations - DWER records (A1861344)
2 1
W o r k s A p p r o v a l : W 6 3 5 5 / 2 0 2 0 / 1
I R - T 0 4 D e c i s i o n R e p o r t T e m p l a t e v 2 . 0 ( J u l y 2 0 1 7 )
Appendix 2: Summary of applicant’s comments on risk assessment and draft conditions
Condition Summary of Licence Holder comment DWER response
S c h e d u l e 1 : M a p 2 “Part of the windrow upgrade works the opportunity was
taken to relocate a section of the southern part of the pipeline to along an existing haul road. This relocation was completed to remove the risk of impacts to vegetation, and for ease of containment bunding.” T h e A p p l i c a n t p r o v i d e d a r e v i s e d m a p s h o w i n g t h e p i p e l i n e r o u t e a n d r e q u e s t e d t h e m a p i n t h e d r a f t d e c i s i o n r e p o r t a n d w o r k s a p p r o v a l b e u p d a t e d w i t h t h e m a p ?
T h e r e l o c a t i o n o f t h e p i p e l i n e i s t o r e d u c e r i s k s o f i m p a c t t o v e g e t a t i o n . T h e m a p i s u p d a t e d .
D W E R n o t e s t h a t t h e r e l o c a t i o n h a s b e e n u n d e r t a k e n p r i o r t o t h e w o r k s a p p r o v a l b e i n g i s s u e d . T h e p i p e l i n e p u r p o s e i s f o r p u r p o s e o f c o n t i n u e d p r o v i s i o n o f w a t e r f o r t h e M i n e s i t e o p e r a t i o n s u n t i l t h e w o r k s a p p r o v a l i s i s s u e d , a n d f l o w r e v e r s e d f o r d e w a t e r i n g o f t h e K a r a r a p i t .
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Works Approval: W6355/2020/1
IR-T04 Decision Report Template v2.0 (July 2017)
