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Upgrade of multi-user seawater supply and introduction of wastewater to ocean outfall, Burrup Peninsula, Change to Environmental Conditions Water Corporation Section 46 Report and Recommendations of the Environmental Protection Authority Environmental Protection Authority Perth, Western Australia Bulletin 1044 March 2002

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Upgrade of multi-user seawater supply and introduction of wastewater to ocean outfall,

Burrup Peninsula, Change to Environmental Conditions

Water Corporation

Section 46 Report and Recommendationsof the Environmental Protection Authority

Environmental Protection AuthorityPerth, Western Australia

Bulletin 1044March 2002

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ISBN. 0 7307 6675 6ISSN. 1030 - 0120Assessment No. 1419

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ContentsPage

1. Introduction and background................................................................................................ 1

2. The proposal .......................................................................................................................... 2

3. Consultation........................................................................................................................... 6

4. Relevant environmental factors ........................................................................................... 7

4.1 Marine flora and fauna ....................................................................................................... 7

4.2 Visual amenity................................................................................................................. 13

5. Conditions and commitments .............................................................................................. 15

5.1 Recommended commitments............................................................................................ 15

5.2 Recommended conditions ................................................................................................ 15

6. Conclusions .......................................................................................................................... 15

7. Recommendations ............................................................................................................... 16

Table

1. Summary of key proposed project modifications ................................................................... 4

Figure

1. Pipeline Route...................................................................................................................... 3

Appendices

1. List of Submitters2. References3. Preliminary Environmental Factors4. Statement of Environmental Conditions of Approval (22 June 2001)5. Recommended Environmental Conditions and Proponent�s Consolidated Commitments6. The Water Corporation's Responsibilities7. Burrup Fertilisers Pty Ltd wastewater and brine discharge

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1. Introduction and background

The Minister for the Environment and Heritage has requested the Environmental Protection Authority (EPA) to consider and provide advice under Section 46(3) of the Environmental Protection Act1986 on the Water Corporation�s proposal to upgrade the proposed multi-user seawater supply system on the Burrup Peninsula.

The Water Corporation submitted a proposal �Burrup Peninsula Desalinated Water and Seawater Supplies Project� in May 2001 (Water Corporation, 2001a) to service the requirements of new industrial developments on the Burrup Peninsula. The proposed scheme was designed to supply seawater and desalinated water to the Syntroleum Sweetwater Corporation (Syntroleum) gas to liquids plant, with additional capacity to supply one or possibly two other process plants. The EPA released its report (EPA, 2001) in May 2001 and approval was granted in June 2001 (Ministerial Statement 567) for a 6.5 megalitres per day (ML/d) thermal desalination plant to be located on Syntroleum�s lease and for a seawater supply (100 ML/d) and brine discharge (77 ML/d) system.

The Water Corporation submitted a proposal in December 2001 (Water Corporation, 2001b) to construct a 4 ML/d thermal desalination plant on Burrup Fertilisers Pty Ltd (Burrup Fertilisers) lease. The proposal included the construction of approximately 1.6 kms of additional seawater supply and brine discharge pipelines from the Syntroleum supply pipeline to Burrup Fertilisers� lease. Anincrease in capacity of the overall seawater supply and brine discharge system was not required. The EPA considered that the existing Ministerial Conditions were adequate and that the proposal did not need to be formally assessed by the EPA.

Burrup Fertilisers was granted approval on 20 February 2002 to construct and operate an ammonia plant within the King Bay � Hearson Cove Industrial Area (Ministerial Statement 586). The EPA approved the discharge of a waste stream from Burrup Fertilisers into the Water Corporation�s proposed brine disposal system.

The Water Corporation now proposes to upgrade its original proposal (Water Corporation, 2001a) to include the provision of water supply to other industrial process plants proposed for the Burrup Peninsula. The proponent estimates the total seawater demand and brine discharge of these plants to be 280 ML/d and 208 ML/d respectively. The proposal also allows for the disposal of industrial wastewater with the brine discharge. As the proposed increase in capacity of the seawater supply and brine discharge system is significant and includes the co-disposal of industrial wastewater with the brine discharge, the Minister for the Environment and Heritage requested the EPA to inquire into and report on the proposed changes.

Further details of the proposal are presented in Section 2 of this Report. Section 3 discusses the consultation undertaken by the proponent. Section 4 discusses environmental factors relevant to the proposal. The conditions and procedures to which the proposal should be subject, if the Minister determines that it may be implemented, are set out in Section 5. Section 6 presents the EPA�s conclusions and Section 7, the EPA�s Recommendations.

A list of people and organisations that made submissions is included in Appendix 1 and References are listed in Appendix 2. The environmental factors considered during the assessment are listed in Appendix 3. Environmental Condition Statement 567, published on 22 June 2001 is presented in Appendix 4. The recommended conditions and procedures and proponent�s commitments are

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provided in Appendix 5. The Water Corporation�s responsibilities are outlined in Appendix 6. Burrup Fertilisers� proposed wastewater and brine discharge is characterised in Appendix 7.

2. The proposal

The Water Corporation proposes the following main changes to the proposal �Desalination and Seawater Supplies Project, Burrup Peninsula� (Water Corporation, 2001a):

• An increase in the capacity of the seawater supply system from 100 ML/d to 280 ML/d;

• An increase in the capacity of the brine discharge into King Bay from 77ML/d to 208 ML/d; and

• The inclusion of approved discharges of treated industrial and domestic wastewater into the brine discharge stream.

The system will essentially be unchanged, although a surge tank (2 ML) and break tank (2 ML) are now required to control the large increase in flow of the seawater supply and brine discharge. An increase in the size of all pumps, pipes and associated plant is required. The location of the seawater intake within the Mermaid Marine harbour and on-shore chlorination and filtration facilities remain unchanged. The outfall diffuser for the brine discharge will be installed between the shipping channels servicing the Woodside Supply Base and Mermaid Marine as originally proposed, but will be located approximately 75m further south and extend an additional 500m further west into deeper water. The proposed pipeline route and associated equipment is shown in Figure 1. The proposal does not include any additional infrastructure to manage wastewater disposal with the brine. Table 1 summarises the key project characteristics of the approved project and proposed modification. A detailed description of the proposal is provided in Section 2 of the SECTION 46 (WaterCorporation, 2002).

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Table 1: Summary of key proposed project modifications

Element Description

Project Purpose To provide high purity water and seawater to proposed industries on the Burrup Peninsula.

No change

Project Life 25 + years No changeMajor Project Components

• Seawater supply pipelines (to 1.4m diameter)• 2 ML Seawater surge tank at the Three Sisters site• Brine discharge pipelines (to 1.1m diameter)• 2 ML brine break tank adjacent to Mermaid Marine, outfall pipe and

diffuser array into King Bay• 33 kV power line • Thermal desalination plant, including cooling tower, seawater storage

tank and desalinated water storage tank at the Syntroleum site• Thermal desalination plant , including seawater storage tank and

desalinated water storage tank at the Burrup Fertilisers site• Potentially, future desalination plants and associated infrastructure at

other developers sites

Larger diameterNewLarger diameterNew

Changed voltageNo change

No change

New

Plant Location • Seawater intake pump system � within the Mermaid Marine harbour development

• Seawater pipelines � within easements on the northern side of the mudflat north of Hearson Cove Road, eastern side of Burrup Road, northern side of King Bay Road and western side of the Mermaid Marine access road and property

• Brine pipelines � adjacent to seawater pipelines• 33 kV power line � adjacent to seawater and brine pipelines• Syntroleum Desalination plant � within the Syntroleum lease area,

adjacent to the process plant site, King Bay-Hearson Cove Industrial Area

• Burrup Fertilisers Desalination plant � within the Burrup Fertilsers lease area, adjacent to the process plant site, King Bay-Hearson Cove Industrial Area

• Brine outfall and diffuser � extending approximately 800 m from the end of the Mermaid Marine groyne to a point approximately midway between the Mermaid Marine and Woodside shipping channels at 4.0m CD.

No change

No change

No changeNo changeNo change

No change

Longer, more diffusers

Plant Operation Continuous � 24 hours per day, 365 days per year No change

Storage Capacities • Seawater service tank (Three Sisters site) - 2ML • Brine break tank (adjacent Mermaid Marine) - 2 ML • Syntroleum desalination plant seawater storage tank � 2 ML• Syntroleum desalination plant distilled water storage tank � 4 ML• Burrup Fertilisers desalination plant seawater storage tank � 2 ML• Future tanks at other developers sites

NewNewNo changeNo changeNo change

Inputs:

- Seawater Ultimately, 280 ML/d intake (including process cooling water) Larger flow- Power Supply • Pump station � ultimately, approximately 3 MW, supplied from process

plantsLarger demand

• Syntroleum Desalination Plant � approximately 1.5 MW supplied from Syntroleum

No change

• Burrup Fertilisers Desalination Plant � approximately 3 MW supplied from Burrup Fertilisers

No change

• Potentially, other desalination plants at other developers sites

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Element Description

Discharges:- Brine Ultimately, approximately 208 ML/d at up to 55,000 mg/L TDS Larger flow- Process

wastewaterBurrup Fertilisers � 0.8 ML/dPotentially, similar quantities from other developers sites.

NewNew

- Domestic wastewater

Burrup Fertilisers � 0.04 ML/dPotentially, similar quantities from other developers sites.

NewNew

- Antiscalant Syntroleum desalination plant - 100 kg/dBurrup Fertilisers desalination plant � 100 kg/dPotentially, similar quantities from other developers sites.

No changeNo changeNew

- Biocide Nil; decomposed by addition of sodium metabisulphite. No change- Sulphamic Acid Nil. No change- Temperature Discharge less than 5oC (less than 2oC for 80% of the time) above ambient

seawater temperature.No change

- Heat Load Ultimately, approximately 208 ML/d nominally within 2°C of the ambient seawater temperature

Increased

Noise:- Construction: Less than 30 dB(A) at the nearest permanent residence (Dampier)- Operation: • Seawater intake system: Less than 70 dB(A) at 1m from pump well.

• Syntroleum Desalination plant: Less than 30 dB(A) at the nearestpermanent residence (Dampier).

• Burrup Fertilisers Desalination plant: Less than 30 dB(A) at the nearest permanent residence (Dampier).

• Future desalination plants at other developers sites are likely to be very similar in nature and sound level at Dampier will be less than 30 dB(A).

No changeNo change

No change

ConstructionPeriod

Approximately 20 months No change

ConstructionWorkforce

Peak 50 No change

OperationalWorkforce

Estimated 6 No change

Project Benefit Provides a reliable, cost effective and environmentally sensitive water supply for industry development on the Burrup Peninsula

No change

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3. Consultation

The proponent has consulted the following principal stakeholders about the proposed changes to the original proposal (Water Corporation, 2001a):

• Dampier Port Authority;

• Dampier Salt Pty Ltd;

• Karratha Districts Chamber of Commerce and Industry;

• Hamersley Iron Pty Ltd;

• Mermaid Marine;

• Department of Conservation and Land Management;

• Department of Environmental Protection � Karratha Branch;

• Shire of Roebourne;

• Ministry for Planning and Infrastructure;

• Office of Major Projects;

• The Conservation Council;

• North- West Telegraph; and

• ABC Radio.

Consultation with stakeholders has occurred through meetings, pamphlets and newspaper briefings. Consultation meetings were held at Karratha on 4-5 February 2002. The stakeholder andcommunity comments indicated general widespread support for the project. The proponent advised that several issues relating to service corridor issues were raised which were relayed to the Office of Major Projects who is overseeing the coordination of the services. Several concerns were also raised that related to general development within the King Bay � Hearson Cove Industrial Area, including the expected traffic increase on Burrup Road and the need to maintain access to Carrie Cove.

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4. Relevant environmental factors

Section 46(3) of the Environmental Protection Act 1986 requires the EPA to report to the Minister for the Environment and Heritage on whether or not the proposed changes to conditions or procedures should be allowed. In addition, the EPA may make recommendations as it sees fit.

It is the EPA�s opinion that its inquiry into the proposed modification to the �Desalination and Seawater Supplies Project, Burrup Peninsula� (Water Corporation, 2001a) should address in detail the following relevant factors:

(a) Marine flora and fauna; and

(b) Visual amenity;

The above relevant factors were identified from the EPA�s consideration and review of allenvironmental factors (preliminary factors) generated from the S46 document and the submissions received, in conjunction with the proposal characteristics (including significance of the potentialimpacts), the adequacy of the proponent�s response and commitments, and the effectiveness of current management (Table A of Appendix 3).

The environmental significance of the above issues of the proposal and their assessment arediscussed in Sections 4.1 and 4.2 of this report. The description of each issue shows how it relates to the project. The assessment of each issue, combined with the consideration of the environmental factors relevant to it, is where the EPA considers if the proposal can be managed to meet its environmental objectives.

4.1 Marine flora and fauna

Description

Western Australia�s coral reefs stretching from the North-West Cape to Perth have been ranked among the most diverse marine environments in the world. The coral reefs of the DampierArchipelago are a significant feature of the Pilbara coastal marine environment (CALM, 1994). However, information available to date indicates that no coral communities or extensive sea grass beds exist within the confines of King Bay (Water Corporation, 2001a).

The proposal has the potential to impact on the marine flora and fauna during:

• Construction of the proposed seawater intake and brine outfall facilities; and

• Operation of the seawater supply and brine and wastewater discharge system.

Construction of inlet and outlet facilities

IRC Environment (IRC Environment, 2001) conducted a benthic mapping survey to document corals and benthic macrophytes in the vicinity of the location of the seawater inlet and brine discharge as initially proposed. The marine survey recorded that the seabed near the proposed area consisted of mud, sand and coarse shell fragments. Marine habitats and biota were found to be

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relatively sparse and typical of habitats widely distributed in the Dampier region. None of the marine biota observed in the area were listed as especially protected, endangered, vulnerable or threatenedunder the Commonwealth Environmental Protection and Biodiversity Conservation Act or the Western Australian Wildlife Protection Act.

The Water Corporation has not conducted a marine survey to date in the proposed new location for the marine outfall. However, the Water Corporation has committed to undertake the survey prior to construction. It is anticipated that marine habitats and biota in vicinity of the new location for the pipeline outfall would be consistent with the findings of the previous survey. In addition the proposed location of the pipeline is between two shipping channels (Suicide Alley) and the proponent has advised that the area is already highly disturbed.

The proposed amendment will result in the disturbance of an additional hectare of the seabed due to the trenching and burial of the additional section of sub-sea pipeline and longer diffuser array. The total area of disturbance now being approximately 2 hectares or about 2% of the King Bay seabed. Based on the information provided to date, direct impacts are expected to be mostly restricted to infauna (animals inhabiting the sediments). The proponent will submit a dredging and spoil disposal plan prior to construction and has committed to employ �best practice� dredging techniques to minimise the environmental impacts. The impacts from construction of the offshore pipeline are described in detail in Section 6.2 of the proponent�s EPS document (Water Corporation, 2001a).

Operation of the seawater supply and brine discharge system

A hydrodynamic assessment was undertaken by Worley (Worley, 2001) for the initial proposal (70 ML/d brine discharge). Modelling predicted that the ANZECC (1992) Guidelines for protection of aquatic ecosystems would not be met for salinity within a 40m radius of the outfall (i.e. a 25 dilutions mixing zone). Modelling also predicted that within 7m and 110m of the outfall the temperature elevation above ambient would be less than 20 C and 0.250 C respectively.

The Environmental Fluid Dynamics Code (EFDC) model was used to simulate the hydrodynamics of the upgraded scheme (208 ML/d brine and wastewater discharge). It demonstrated that asubstantially larger mixing zone (0.6 km2 or 1 km x 0.6 km) is now required to meet the guidelines for aquatic ecosystems for salinity. The results of the modelling are described in Section 4 of the proponent�s document (Water Corporation, 2002). The impacts of the salinity and temperature on the natural system, and the dispersion characteristics of a conservative dye tracer were examined for a 14 day winter period. The key findings of the model are as follows:

• The salinity variation as a result of the discharge is not greater than 5% above the ambient level more than 1% of the time anywhere within King Bay apart from within the proposed mixing zone;

• The maximum stratification due to the high salinity release is approximately 1ppt within the Mermaid Marine and Woodside dredged channels and basins. This is the same level of stratification that was predicted to occur due to the discharge from the 100 ML/d scheme;

• The temperature elevation is predicted to be less than 0.250 C less than 40m from the outfall, although the 14 port diffuser now extends for 260m. Natural seawater temperature variation of around 2°C in a tidal cycle was measured in the outfall location during the summer of 2000 � 2001 (Water Corporation, 2001a); and

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• It is expected that within the mixing zone for salinity (0.6 km2), a contaminant dilution of at least 25 times will be achieved at the seabed level for more than 95% of the time.

The two coral communities known to occur just outside King Bay (Phillip Point and Parker Point) are both located approximately 700m from the proposed outfall.

The original proposal included one thermal desalination plant on Syntroleum�s lease. An additional thermal desalination plant has been approved on Burrup Fertilisers� lease and the current proposal potentially allows for additional desalination plants to be located on other industrial leases. Inaddition to elevated salt concentrations and temperature levels, discharges from thermal desalination plants may have the following types of potentially adverse constituents and qualities:

• Turbidity levels above those of receiving waters;

• Oxygen levels below those of receiving waters;

• Chemicals from pre-treatment of feedwater (including biocides and antiscalants);

• Chemicals used in flushing pipelines;

• Concentration of organics and metals in the feedwater through the desalination process; and

• Metals picked up by brine in contact with plant components and pipelines.

The proponent has advised that each desalination plant requires approximately 100kg/d ofantiscalant (sodium salt of a polycarboxylic acid) and low concentrations of biocides (typicallychlorine). Initial acute toxicity tests indicate that some carboxylic acid antiscalants may not be harmful to the marine biota at the anticipated does rate (typically less than 2 mg/L in the brine discharge), but additional information is required on the toxicity and fate consequence of the discharge. The residual biocide will be continuously monitored and de-chlorinated by the addition of sodium metabisulphite to produce ions naturally present in seawater. The Water Corporation will monitor these chemical additives and other environmental parameters at the outfall as part of their overall Environmental Management Program.

Wastewater Discharge

The Water Corporation proposes to utilise the brine discharge system for the disposal of treated industrial and domestic wastewater from industries in the King Bay � Hearson Cove Industrial Area. The Water Corporation has outlined its responsibilities in managing the multi-user brine andwastewater discharge system as shown in Appendix 6.

The Water Corporation as owners and managers of the brine and wastewater discharge system will monitor and report on the individual effluent streams entering, and the combined discharge leaving, the system. It has committed to implement an Environmental Management Program that includes appropriate monitoring and reporting, encompassing water, sediment and biota, for the wastewater system and the ambient environment. The Water Corporation has committed to impose contractual obligations on system users with respect to the flow and composition of their discharge into the multi-user discharge system. It will independently sample and analyse the individual discharges on a regular basis to validate the accuracy of the data provided by system users.

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Only industries that have received the appropriate environmental approval would be permitted to discharge their wastewater into the brine discharge system. The wastewater discharged from each industrial premises would be subject to specific Ministerial Conditions and/or licence conditions. Industries will be required to monitor their combined brine and wastewater discharge prior to entry into the Water Corporation discharge system to ensure compliance with Ministerial and licence conditions. The Water Corporation will develop an investigation/management plan in consultation with the EPA/DEP and industry in order to provide an appropriate response should monitoring identify unacceptable impacts on the environment or if agreed criteria are not met.

To date the only proposal within the King Bay � Hearson Cove Industrial Area to receive MinisterialApproval for wastewater discharge is Burrup Fertilisers� ammonia plant. This proposal included a wastewater and brine discharge to the Water Corporation�s proposed system. The discharge stream proposed by Burrup Fertilisers is characterised in Appendix 7 and is considered to represent best practice. It is expected that this treated wastewater and brine combined will meet the ANZECC & ARMCANZ (2000) 99% species protection criteria for toxicants on entry into the brine discharge system.

Dampier Salt Option

Dampier Salt operates a large salt production facility approximately 9 kms south west of King Bay. It produces salt primarily for industrial use by the solar evaporation of seawater. The annual average seawater intake being approximately 410 ML/d.

During the preliminary design phase for the Burrup Peninsula Desalinated Water and Seawater Supply project, Dampier Salt expressed reservations about accepting brine from the scheme based on the relatively small flow rate (77 ML/d) and high capital and operating cost of transport to the evaporation ponds. However, with the significantly larger volume of brine available in the revised proposal for multiple industrial projects, the proponent has advised that Dampier Salt has indicated an interest in utilising the brine from the cooling tower circuits and desalination plants. Reservationshave been expressed about chemical additives (antiscalants, biocides, etc) used in the processes. Dampier Salt has reserved judgment on the potential for accepting domestic wastewater or process wastewater into the salt process without detailed examination of the nature and concentration of contaminants. Management of the salt farm is a complex operation, with the process typically taking approximately 2 years from seawater inlet to crystalline salt shipment. Nutrients in the seawater are managed within the brine ponds by careful cultivation of brine shrimp and milkfish.

The Water Corporation has advised that Dampier Salt has estimated a feasibility study foracceptance of the brine and wastewater will take up to two years. The study will include the economics of the transfer scheme as well as operational implications for Dampier Salt.

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Agency and public comments

CALM considers that the option of disposal to Dampier Salt is the preferred option and is prepared to assess this component once the study has been completed. CALM supports the proposal of providing common user facilities to all plants on the Burrup Peninsula. However, it has raised a number of concerns as follows:

• the seawater supply and brine discharge pipelines as proposed, may restrict the ability to provide further services to and from each industrial site. It considers that the WaterCorporation and Office of Major Projects should advise the measures that are being takento ensure that there will be adequate room in the service corridors for future services to each site;

• the outfall diffuser array may be damaged by shipping or construction activities in the proposed location (Suicide Alley) and that damage to this facility may lead to unacceptable levels of pollution. An appropriate body should review protection measures proposed to ensure damage will not occur;

• there appears to be minimal assessment of the benthic fauna in the outfall mixing zone, or review of the relevant results. The WA Museum�s recent surveys indicate that molluscs and echinoderms have highly patchy distributions. CALM recommends that the WaterCorporation provides CALM and the WA Museum with the results of the marine survey and consults with the Museum on the significance of the site; and

• toxicity testing should be undertaken to determine the impacts on local fauna includingechinoderms and sponges that inhabit the area.

The Water Corporation has been consulting with CALM to address these matters.

Assessment

The area considered for assessment of this factor is the marine environment of King Bay and Mermaid Sound.

The EPA�s environmental objective for this factor is to maintain marine ecological integrity and biodiversity and ensure that any impacts on locally significant marine communities are avoided. It considers that the surrounding waters of the Dampier Archipelago are of high environmental value, with areas designated as nature reserves and the establishment of a marine conservation reserve is being considered.

The EPA supports the proposal of providing common user facilities to new industrial plants on the Burrup Peninsula. The EPA considers the utilisation of the warm brine discharge as a �feed stock� for Dampier Salt to be a sustainable option should it prove to be feasible in the future. It would have been helpful for waste minimisation and re-use to have been fully explored earlier so that it could be considered as part of this assessment. However, the EPA notes that the proponent has committed to complete a comprehensive feasibility study of this option in the near future and that the brine and wastewater system will be designed to allow retro-fitting in the future should any brine re-use option be found to be feasible. The EPA also considers that there maybe the opportunity for other wastewater minimisation/re-use options between industries in the King Bay Hearson Cove Industrial Area. The EPA encourages the Water Corporation to meet with system users on an ongoing basis to

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explore opportunities to minimise potential environmental impacts within King Bay and possiblyachieve operational savings.

As the proposed brine and wastewater discharge maybe long-term, the EPA believes that a precautionary approach must be taken with respect to setting discharge limits for toxicants and chemical stressors to provide a high level of certainty that the surrounding waters of Mermaid Sound are protected.

Construction Impacts

The EPA notes that marine biota and habitats in King Bay are relatively sparse as a result of the natural turbidity of the bay and that some areas are already degraded due to dredging activities. It has previously concluded that the environmental impacts resulting from the construction of a 500m subsea pipeline within King Bay would not be significant as only local infauna will be affected (EPA, 2001). The EPA considers that any additional impacts resulting from construction of the additional section of pipeline is unlikely to be significant, but requires the Water Corporation to provide anassessment of the benthic fauna in the vicinity of the area to be impacted, prior to construction. The EPA considers that the construction management strategy previously proposed by the WaterCorporation, along with the existing Ministerial Conditions will also be satisfactory for the proposed extension.

Operation Impacts

The EPA notes that the proposed increase in capacity of the brine and wastewater discharge will result in the ANZECC (1992) guideline for salinity being met at the edge of a mixing zone of 0.6 km2

rather than the original mixing zone of 0.01 km2. The EPA considers that any environmental impacts on the marine flora and fauna due to this increase to be acceptable for the chemical stressor, salinity. The EPA notes that modelling has predicted that the temperature elevation at 40m from the outfall is expected to be no more than 0.250C. The EPA considers that the impact from the additional heat load as a result of an increase in capacity of the discharge would be acceptable, given that the nearest known coral communities are approximately 700m from the proposed outfall. However, the EPA considers there is a need to formally develop temperature and salinity criteria for the Dampier Archipelago.

The EPA considers that even if the Water Corporation proposal, when fully implemented, met the ANZECC & ARMCANZ (2000) 99% species protection level for toxicants at the edge of the proposed mixing zone for salinity (0.6 km2) it could potentially permit unacceptably high loads of metals and other toxicants. The EPA accepts that it is difficult to determine an appropriate mixing zone for toxicants at this stage due to the lack of suitable data on the naturally occurringconcentrations of contaminants in seawater and uncertainty associated with the types andconcentrations of contaminants generated by other potential system users. However, the EPAexpects the mixing zone for toxicants to be defined once the brine and wastewater system is operational and to be revised as additional industries connect into the system and our understanding of the consequences of these types of discharge to the King Bay area improves through the results of environmental monitoring programs. In the absence of data on the likely fate and consequence of potentially significant loads of contaminants to King Bay, the EPA considers that any mixing zone for toxicants would need to be significantly smaller than for salinity and that during the environmental approvals process each industry should demonstrate waste avoidance/minimisation strategies and meet �best practice�. As a guide the edge of the previously approved mixing zone (0.01 km2) can be

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used as the 99% species protection level for toxicants to assist the Water Corporation in its management of the outfall.

Management Strategy

The EPA endorses the proposed management strategy by the Water Corporation that only industries that have received the appropriate environmental approval (Ministerial conditions and or licence conditions) by the EPA and/or DEP would be permitted to discharge their wastewater into the brine discharge system. Through the environmental approval process, individual system users will be required to:

• demonstrate �best practice� and waste minimisation principles;

• demonstrate that the cumulative impacts on the marine environment are acceptable; and

• monitor the constituents of the wastewater and brine prior to entry to the Water Corporation discharge system.

The EPA is satisfied that the Water Corporation will implement a monitoring program/plan to effectively monitor and report on both non-compliance and potential impacts on the marineenvironment by the brine and wastewater discharge. If monitoring identifies that guideline trigger values are exceeded outside the relevant defined mixing zone, the EPA expects the WaterCorporation to undertake further site specific investigations to assess the potential risk. If the potential risk is high, a coordinated management response will be required by the WaterCorporation, the DEP and system users to reduce contaminant inputs to the ambient environment and achieve the environmental quality objectives within an agreed timeframe. The EPA expects the Water Corporation to outline an effective management response as part of its EnvironmentalManagement Plan.

Summary

Having particular regard to the:

(a) environmental quality objectives for King Bay and Mermaid Sound being met outside an approved mixing zone;

(b) commitments made by the proponent, particularly regarding the continued investigation of the reuse options; and

(c) proposed management strategy including the requirement for system users to gain environmental approval for the discharge of their effluent into the brine and wastewater discharge system;

it is the EPA�s opinion that the proposal can be managed to meet the EPA�s environmental objectivefor marine flora and fauna.

4.2 Visual Amenity

Description

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In the original proposal the section of seawater supply and brine discharge pipelines within the King Bay � Hearson Cove valley were to be buried as shown in Figure 2.1 of the proponents EPS (Water Corporation, 2001a). However, preliminary drilling results from within the service corridors indicates that it may not be practicable to bury the seawater supply pipeline (up to1.4m diameter) and brine and wastewater discharge pipeline (up to 1.1m diameter). A large proportion of the holes could not be drilled to 1m and it is expected that blasting would be required in order to bury the pipelines. There is also concern that burying the pipelines in the east-west corridor south of Burrup Fertilisers� lease could form a drainage barrier across the northern section of the mudflats.

Although the King Bay � Hearson Cove valley has been designated for industry, above ground pipelines will further reduce the visual amenity of the area, particularly when viewed from the Hearson Beach Road. The Water Corporation has committed to paint the pipelines in colours that blend in with the environment.

Assessment

The area considered for assessment of this factor is the King Bay � Hearson Cove Industrial Area.

The EPA�s environmental objective for this factor is to ensure that the proponent considers aesthetic values, and that measures are put in place to reduce the visual impacts of the developments on the surrounding country side as low as reasonably practicable.

The EPA notes that initial tests indicate that burying the pipelines in the tidal mudflats of the King Bay � Hearson Cove valley may not be practicable. The EPA considers that above ground pipelines painted to blend in with the environment would be acceptable. Although less aesthetically pleasing, the installation of above ground pipelines is expected to result in less disturbance to the environment and the natural landform of the Burrup Peninsula, including potential impacts from restrictions to the flow of subsurface water.

Summary

Having particular regard to the King Bay � Hearson Cove valley being set aside for industry it is the EPA�s opinion that the proposal can be managed to meet the EPA�s environmental objective for visual impacts.

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5. Conditions and commitments

Section 46(3) of the Environmental Protection Act 1986 requires the EPA to report to the Minister for the Environment and Heritage on whether or not the proposed changes to conditions or procedures should be allowed. In addition, the EPA may make recommendations as it sees fit.

In developing recommended conditions for each project, the EPA�s preferred course of action is to have the proponent provide an array of commitments to ameliorate the impacts of the proposal on the environment.

5.1 Recommended commitments

The Water Corporation has made changes to commitments to reflect discussions with the DEP which have been part of the assessment process. The proponent�s commitments as set out in the Section 46 document (Water Corporation, 2002) and subsequently modified, as shown in Appendix 5, should be made enforceable conditions.

5.2 Recommended commitments

Having considered the proponent�s commitments and the information provided in this report, the EPA recommends that the following conditions be imposed if the proposal by the Water Corporation is approved for implementation:

(a) The existing Ministerial Conditions applied to the project (Ministerial Statement 567published on 22 June 2001), be subject to modifications necessary to:

• implement the revised consolidated environmental management commitments of 19 March 2002.

The amended conditions and amended Consolidated Commitments statement are presented in Appendix 5.

6. Conclusions

The EPA has considered the proposal by the Water Corporation to upgrade the multi-user seawater supply and introduce wastewater to the ocean outfall and has concluded that it can be managed to meet the EPA�s objectives for the relevant environmental factors.

The EPA considers the utilisation of the warm brine discharge as a �feedstock� for Dampier Salt a more sustainable option should it prove to be feasible in the future. However, the EPA concludes that the environmental impacts on King Bay and the surrounding water as a result of the proposed increase in the capacity of the seawater supply (280 ML/d) and brine discharge (208 ML/d) will be acceptable, given the commitment made by the Water Corporation to implement an Environmental Management Program that includes appropriate monitoring and reporting, encompassing water, sediment and biota, for the outfall and the ambient environment. The EPA also considers that it is

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16

acceptable to incorporate industrial and domestic wastewater into the Water Corporation�sdischarge system from industries that have received environmental approval.

In addition to the above, the EPA considers that conditions attaching to the environmental approval should be updated. It has therefore reported also on the updating of conditions.

7. Recommendations

The EPA submits the following recommendations to the Minister for the Environment and Heritage:

1. That the Minister notes that this report is pursuant to Section 46(3) of the Environmental Protection Act 1986 and thus is limited to consideration of proposed changes to the original conditions.

2. The Minister notes that the proposed change is to increase the capacity of the seawater supply and brine discharge system to service the requirements of new industrial process plants proposed for the Burrup Peninsula. The proposed change also allows for the disposal of industrial and domestic wastewater with the brine discharge.

3. The EPA recommends that the Minister considers the report on the relevant environmental factors as set out in Section 4.

4. That the Minister notes that the EPA has concluded that the modified proposal can be managed to meet the EPA�s objectives, and thus not impose an unacceptable impact on the environmental provided there is satisfactory implementation by the proponent of the amended conditions, including the proponent�s commitments, as set out in Section 5.

5. The Minister imposes the amended conditions, commitments and procedures recommended in Appendix 5 of this report.

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Appendix 1

List of Submitters

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State/Local Government

The Department of Conservation and Land Management

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Appendix 2

References

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ANZECC (1992). Australian Water Quality Guidelines for Fresh and Marine Waters.

ANZECC & ARMCANZ (2000). Australian and New Zealand Guidelines for Fresh and Marine Water Quality � National Water Quality Management Strategy. Australian and NewZealand Environment and Conservation Council Agriculture and Resource Management Council of Australia.

Astron Engineering (1998). Investigative Sampling at King Bay.

Burns and Roe Worley, (2001). Burrup Peninsula Desalinated Water and Seawater Supplies Project Environmental Protection Statement.

CALM (1994). A Representative Marine Reserve System for Western Australia. A Report of the Marine Parks and Reserves Selection Working Group.

EPA (2001). Desalination and Seawater Supplies Project, Burrup Peninsula.

IRC Environment ( 2001). Water Corporation Dampier Marine Environmental Survey.

Water Corporation (2001a). Burrup Peninsula Desalinated Water and Seawater SuppliesProject Environmental Protection Statement

Water Corporation (2001b). Burrup Peninsula Desalinated Water and Seawater SuppliesProject, Burrup Fertilisers Extension.

Water Corporation (2002). Burrup Peninsula Desalinated Water and Seawater SuppliesProject - Referral for Section 46 Amendment to Environmental Protection Statement.

Worley (2001). Burrup Peninsula Desalination Plant Hydrodynamic Assessment.

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Appendix 3

Summary of Preliminary Factors

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Tabl

e A

SUM

MA

RY

OF

PREL

IMIN

AR

Y E

NV

IRO

NM

ENTA

L FA

CTO

RS

Envi

ronm

enta

lFa

ctor

sEP

A M

anag

emen

t Obj

ectiv

ePo

tent

ial I

mpa

ctPr

opos

ed M

anag

emen

t of R

elev

ant

Envi

ronm

enta

l Fac

tors

Pred

icte

d O

utco

mes

BIO

PHYS

ICA

L IM

PAC

TS

Terre

stria

l Flo

raTo

ens

ure

that

, whe

re p

ossi

ble,

im

pact

s upo

n re

gion

ally

sign

ifica

nt

flora

and

veg

etat

ion

com

mun

ities

are

av

oide

d an

d to

ens

ure

the

abun

danc

e, d

iver

sity

, geo

grap

hica

ldi

strib

utio

n an

d pr

oduc

tivity

of

vege

tatio

n co

mm

uniti

es a

re

prot

ecte

d.

Cle

arin

g of

flor

a an

d ve

geta

tion

durin

g pi

pelin

e co

nstr

uctio

n.

Spre

ad o

f wee

ds

Dev

elop

men

t of c

onst

ruct

ion

plan

(s) t

o in

clud

e:•

iden

tific

atio

n, m

arki

ng a

nd re

loca

tion

of si

gnifi

cant

flor

a an

d ve

geta

tion,

min

imisi

ng a

rea

clea

red

• co

ntro

l of w

eeds

• re

habi

litat

ion

of c

onst

ruct

ion

and

layd

own

area

s

No

sign

ifica

nt o

r las

ting

impa

ct o

n re

gion

ally

si

gnifi

cant

flor

a an

d ve

geta

tion

com

mun

ities

Dec

lare

d R

are

and

Prio

rity

Flor

aTo

pro

tect

Dec

lare

d R

are

and

Prio

rity

flora

, con

sist

ent w

ith th

e pr

ovis

ions

of t

he W

ildlif

eC

onse

rvat

ion

Act 1

950,

and

to

ensu

re th

e ab

unda

nce,

div

ersi

ty,

geog

raph

ical

dis

tribu

tion

and

prod

uctiv

ity o

f veg

etat

ion

com

mun

ities

are

pro

tect

ed.

Inad

verte

nt d

estru

ctio

n of

D

ecla

red

Rar

e Fl

ora

and

Prio

rity

flora

Flor

a su

rvey

to c

lear

ly id

entif

y ra

re o

r prio

rity

flora

spec

imen

s with

in c

onst

ruct

ion

area

s.

Con

stru

ctio

n pl

an to

iden

tify

avoi

danc

e or

re

loca

tion

of id

entif

ied

spec

imen

s.

No

impa

cts o

n D

ecla

red

Rar

e Fl

ora

and

Prio

rity

flora

.

Terr

estri

al F

auna

To e

nsur

e th

at, w

here

pos

sibl

e,

impa

cts u

pon

regi

onal

ly si

gnifi

cant

fa

una

and

habi

tat a

re a

void

ed a

nd

that

the

abun

danc

e, s

peci

es

dive

rsity

and

geo

grap

hica

l di

strib

utio

n of

terr

estri

al fa

una

are

mai

ntai

ned.

Poss

ible

des

truct

ion

ofso

me

habi

tat.

Faun

a ha

bita

t sur

vey

to c

lear

ly id

entif

y si

gnifi

cant

hab

itats

with

in c

onst

ruct

ion

area

s.

Con

stru

ctio

n pl

an to

iden

tify

avoi

danc

e or

re

loca

tion

of id

entif

ied

habi

tat.

No

sign

ifica

nt o

r las

ting

impa

cts o

n re

gion

ally

si

gnifi

cant

faun

a an

d ha

bita

t

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23

Envi

ronm

enta

lFa

ctor

sEP

A M

anag

emen

t Obj

ectiv

ePo

tent

ial I

mpa

ctPr

opos

ed M

anag

emen

t of R

elev

ant

Envi

ronm

enta

l Fac

tors

Pred

icte

d O

utco

mes

Spec

ifica

lly P

rote

cted

(T

hrea

tene

d) F

auna

To p

rote

ct S

peci

fical

ly P

rote

cted

(T

hrea

tene

d) F

auna

, con

sist

ent w

ith

the

prov

isio

ns o

f the

Wild

life

Con

serv

atio

n Ac

t 195

0.

Inad

verte

nt d

estru

ctio

n of

ha

bita

t of S

peci

fical

ly

Prot

ecte

d (T

hrea

tene

d)

Faun

a

Faun

a ha

bita

t sur

vey

to c

lear

ly id

entif

y si

gnifi

cant

hab

itats

with

in c

onst

ruct

ion

area

s.

Con

stru

ctio

n pl

an to

iden

tify

avoi

danc

e or

re

loca

tion

of id

entif

ied

habi

tat.

No

impa

cts o

n Sp

ecifi

cally

Pr

otec

ted

(Thr

eate

ned)

Fa

una

and

thei

r hab

itats

Mar

ine

Flor

aM

aint

ain

the

ecol

ogic

al fu

nctio

n,

abun

danc

e, s

peci

es d

iver

sity

and

ge

ogra

phic

dis

tribu

tion

of m

arin

e flo

ra (s

eagr

ass a

nd m

acro

-alg

ae).

No

seag

rass

or m

acro

-alg

aeco

mm

uniti

es o

ccur

with

in

the

cons

truct

ion

area

.

Brin

e di

scha

rge

may

impa

ct

upon

com

mun

ities

with

in

40m

of t

he d

iffus

ers.

Des

ign

to a

chie

ve b

rine

dilu

tion

to w

ithin

5%

of

ambi

ent s

alin

ity w

ithin

40m

of d

iffus

ers.

Dev

elop

pro

gram

for m

onito

ring

oper

atio

n of

di

ffus

ers.

No

sign

ifica

nt im

pact

s on

mar

ine

flora

(sea

gras

s and

m

acro

-alg

ae)

Man

grov

esM

aint

ain

the

ecol

ogic

al fu

nctio

n,

abun

danc

e, s

peci

es d

iver

sity

and

ge

ogra

phic

dis

tribu

tion

of m

angr

ove

com

mun

ities

and

thei

r ass

ocia

ted

ecos

yste

ms.

Inta

ke a

nd o

utfa

ll ar

e di

stan

t fro

m m

angr

oves

�no

exp

ecte

d im

pact

Dev

elop

pro

gram

for m

onito

ring

oper

atio

n of

diff

user

s.N

o im

pact

s on

man

grov

es

Mar

ine

Faun

aM

aint

ain

the

abun

danc

e, s

peci

es

dive

rsity

and

geo

grap

hic

dist

ribut

ion

of m

arin

e fa

una.

Som

e m

arin

e fa

una

may

be

dest

roye

d du

ring

the

dred

ging

and

con

stru

ctio

n pr

oces

s for

the

outfa

ll.

Dev

elop

men

t of c

onst

ruct

ion

plan

for o

utfa

ll an

d di

ffus

ers t

o ad

dres

s:•

min

imis

ing

area

of d

redg

ing

• m

onito

ring

and

cont

rol o

f tur

bidi

ty

Con

tinuo

us o

n-lin

e m

onito

ring

of b

rine

disc

harg

e tu

rbid

ity

No

sign

ifica

nt im

pact

s on

mar

ine

faun

a.

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24

Envi

ronm

enta

lFa

ctor

sEP

A M

anag

emen

t Obj

ectiv

ePo

tent

ial I

mpa

ctPr

opos

ed M

anag

emen

t of R

elev

ant

Envi

ronm

enta

l Fac

tors

Pred

icte

d O

utco

mes

Cor

al re

efs

Mai

ntai

n an

d pr

otec

t the

abun

danc

e, sp

ecie

s div

ersi

ty,

geog

raph

ic d

istri

butio

n an

d pr

oduc

tivity

of c

oral

reef

s.

Alth

ough

cor

als

are

not

pres

ent w

ithin

the

Kin

g B

ay a

rea,

nea

rby

com

mun

ities

may

be

subj

ect t

o in

crea

sed

susp

ende

d se

dim

ent

load

ings

dur

ing

dred

ging

Dev

elop

men

t of c

onst

ruct

ion

plan

for o

utfa

ll an

d di

ffus

ers t

o ad

dres

s:•

min

imis

ing

area

of d

redg

ing

• m

onito

ring

and

cont

rol o

f tur

bidi

ty

Con

tinuo

us o

n-lin

e m

onito

ring

of b

rine

disc

harg

e tu

rbid

ity

No

impa

ct o

n ne

arby

cor

al

com

mun

ities

Spec

ifica

lly P

rote

cted

(T

hrea

tene

d) F

auna

To p

rote

ct S

peci

fical

ly P

rote

cted

(T

hrea

tene

d) F

auna

, con

sist

ent w

ith

the

prov

isio

ns o

f the

Wild

life

Con

serv

atio

n Ac

t 195

0.

Inad

verte

nt d

estru

ctio

n of

ha

bita

t of S

peci

fical

ly

Prot

ecte

d (T

hrea

tene

d)

Faun

a

Mar

ine

habi

tat s

urve

y to

cle

arly

iden

tify

sign

ifica

nt h

abita

ts w

ithin

con

stru

ctio

n ar

eas.

Con

stru

ctio

n pl

an to

iden

tify

avoi

danc

e or

re

loca

tion

of id

entif

ied

habi

tat.

No

impa

cts o

n Sp

ecifi

cally

Pr

otec

ted

(Thr

eate

ned)

Fa

una

and

thei

r hab

itats

Inte

rtida

l and

subt

idal

zo

neM

aint

ain

the

abun

danc

e, d

iver

sity

and

geog

raph

ic d

istri

butio

n of

m

arin

e flo

ra a

nd fa

una

with

in th

e in

terti

dal a

nd su

btid

al z

one.

Min

or d

istu

rban

ce d

urin

g co

nstru

ctio

n.

No

dist

urba

nce

durin

g op

erat

ion

No

spec

ific

man

agem

ent p

lan

requ

ired.

N

o de

trim

enta

l im

pact

s on

the

inte

rtida

l and

subt

idal

zo

ne o

r loc

ally

sign

ifica

nt

mar

ine

flora

and

faun

a co

mm

uniti

es.

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25

Envi

ronm

enta

lFa

ctor

sEP

A M

anag

emen

t Obj

ectiv

ePo

tent

ial I

mpa

ctPr

opos

ed M

anag

emen

t of R

elev

ant

Envi

ronm

enta

l Fac

tors

Pred

icte

d O

utco

mes

Seab

edD

evel

opm

ent s

houl

d no

t hav

e a

sign

ifica

nt im

pact

on

exis

ting

coas

tal

proc

esse

s, in

clud

ing

offs

hore

se

dim

ent m

ovem

ent.

Dis

turb

ance

dur

ing

cons

truct

ion

(dre

dgin

g).

Roc

k co

ver o

ver o

utfa

ll w

ill

crea

te a

n ar

tific

ial m

icro

-en

viro

nmen

t in

the

Kin

g B

ay a

rea

Poss

ible

cha

nge

in

sedi

men

t tra

nspo

rt du

e to

la

rge

seaw

ater

inta

ke

volu

me.

Det

aile

d ci

rcul

atio

n an

d se

dim

ent t

rans

port

mod

ellin

g fo

r rep

rese

ntat

ive

tidal

and

wav

e co

nditi

ons h

as b

een

unde

rtak

en.

An

asse

ssm

ent

of th

e po

tent

ial i

mpa

cts o

n th

e hy

drod

ynam

ic

and

sedi

men

t tra

nspo

rt re

gim

es li

kely

to o

ccur

in

Kin

g B

ay a

fter d

evel

opm

ent h

as b

een

com

plet

ed.

It w

as c

oncl

uded

that

no

nota

ble

chan

ges t

o th

e ci

rcul

atio

n an

d m

orph

olog

ical

pro

cess

es w

ithin

K

ing

Bay

are

like

ly to

occ

ur a

s a re

sult

of th

e se

awat

er in

take

and

brin

e ou

tfall.

Thi

s inc

lude

s ne

glig

ible

impa

ct o

n th

e ov

eral

l wat

er q

ualit

y an

d flu

shin

g, m

inim

al c

hang

es to

the

sedi

men

t tra

nspo

rt re

gim

e an

d ci

rcul

atio

n an

d no

cha

nge

to th

e ex

istin

g tid

al ra

nge

with

in th

e B

ay.

The

sub-

sea

pipe

line

will

be

rock

cov

ered

. Th

e pi

pe c

over

will

be

as n

ear a

s pos

sibl

e to

exi

stin

g se

a be

d le

vel a

nd c

onto

urs.

Con

tinuo

us o

n-lin

e m

onito

ring

of fl

ow ra

te,

tem

pera

ture

, con

duct

ivity

and

turb

idity

of b

oth

inta

ke a

nd b

rine

disc

harg

e

No

sign

ifica

nt im

pact

on

the

seab

ed.

No

detri

men

tal i

mpa

cts o

n ex

istin

g co

asta

l pro

cess

es

Sea

leve

lTo

ens

ure

that

dev

elop

men

t doe

s no

t inc

reas

e th

e po

tent

ial i

mpa

ct o

n th

e en

viro

nmen

t fro

m st

orm

surg

e.

Ther

e w

ill b

e no

impa

ct o

n th

e se

a le

vel,

tides

or s

torm

su

rge

leve

l

No

man

agem

ent r

equi

red

No

unac

cept

able

en

viro

nmen

tal i

mpa

ct

Land

form

To e

stab

lish

stab

le, s

usta

inab

le

land

form

con

sist

ent w

ith

surr

ound

ings

.

The

pipe

lines

runn

ing

from

th

e M

erm

aid

Mar

ie fa

cilit

y to

the

Synt

role

um si

te w

ill

not c

ause

any

alte

ratio

ns to

th

e la

ndfo

rm

Con

stru

ctio

n pl

an to

iden

tify:

• co

ntro

l of l

evel

s •

eros

ion

cont

rol

No

land

form

deg

rada

tion

will

occ

ur

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26

Envi

ronm

enta

lFa

ctor

sEP

A M

anag

emen

t Obj

ectiv

ePo

tent

ial I

mpa

ctPr

opos

ed M

anag

emen

t of R

elev

ant

Envi

ronm

enta

l Fac

tors

Pred

icte

d O

utco

mes

POLL

UTIO

N M

ANAG

EMEN

TPa

rticu

late

s / D

ust

To e

nsur

e th

at d

ust l

evel

s gen

erat

ed

by th

e pr

opos

al d

o no

t adv

erse

ly

impa

ct u

pon

the

wel

fare

and

am

enity

or

cau

se h

ealth

pro

blem

s by

mee

ting

stat

utor

y re

quire

men

ts a

nd

acce

ptab

le st

anda

rds.

Pote

ntia

l dus

t cre

atio

n du

ring

cons

truct

ion.

No

oper

atio

nal a

ctiv

ities

w

ill c

reat

e du

st.

Con

stru

ctio

n pl

an to

iden

tify

appr

opria

te d

ust

mon

itori

ng a

nd d

ust s

uppr

essi

on.

Poss

ible

smal

l, sh

ort t

erm

du

st p

robl

ems

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27

Envi

ronm

enta

lFa

ctor

sEP

A M

anag

emen

t Obj

ectiv

ePo

tent

ial I

mpa

ctPr

opos

ed M

anag

emen

t of R

elev

ant

Envi

ronm

enta

l Fac

tors

Pred

icte

d O

utco

mes

Gro

undw

ater

qua

lity

and

Mar

ine

wat

er a

nd

sedi

men

t qua

lity

Mai

ntai

n or

impr

ove

the

qual

ity o

f gr

ound

wat

er a

nd m

arin

e w

ater

to

ensu

re th

at e

xist

ing

and

pote

ntia

l us

es, i

nclu

ding

eco

syst

em

mai

nten

ance

are

pro

tect

ed,

cons

iste

nt w

ith E

PA (1

993)

and

N

HM

RC

gui

delin

es w

here

rele

vant

.

Mai

ntai

n or

impr

ove

mar

ine

wat

er

and

sedi

men

t qua

lity

cons

iste

nt w

ith

EQO

�s a

nd E

QC

�s d

efin

ed in

the

Sout

hern

Met

ropo

litan

Coa

stal

Wat

ers S

tudy

(DEP

, 199

6b).

Turb

idity

cre

ated

dur

ing

cons

truct

ion

activ

ities

for

the

brin

e ou

tfall

Brin

e di

scha

rge

will

cre

ate

a zo

ne o

f ele

vate

d sa

linity

ar

ound

the

diff

user

s

Leak

age o

f sea

wat

er fr

om

the

pipe

line

thro

ugh

pipe

line

fittin

gs (e

g ai

r re

leas

e va

lves

) or p

ipel

ine

failu

res.

Cat

astro

phic

failu

re o

f pi

pelin

e ca

usin

g la

rge,

su

dden

rele

ase

of se

awat

er.

Dev

elop

men

t of c

onst

ruct

ion

plan

for o

utfa

ll an

d di

ffus

ers t

o ad

dres

s:•

min

imis

ing

area

of d

redg

ing

• m

onito

ring

and

cont

rol o

f tur

bidi

ty

Des

ign

to a

chie

ve b

rine

dilu

tion

to w

ithin

5%

of

ambi

ent s

alin

ity w

ithin

40m

of d

iffus

ers.

Initi

al sa

mpl

ing

prog

ram

to c

onfir

m p

erfo

rman

ce

of th

e di

ffus

ers t

o de

sign

. O

n-go

ing

regu

lar

visu

al in

spec

tion

of o

utfa

ll.

Dev

elop

com

preh

ensi

ve in

spec

tion

and

mai

nten

ance

pro

gram

for p

ipel

ines

and

fitti

ngs.

Seaw

ater

leak

s fro

m p

ipel

ine

fittin

gs w

ill b

e co

llect

ed a

nd p

umpe

d ba

ck in

to th

e lin

e. A

ny

scou

r sea

wat

er w

ill b

e co

llect

ed a

nd p

umpe

d ba

ck in

to th

e pi

pelin

e an

d no

t allo

wed

to fl

ow

onto

the

grou

nd.

Con

tinuo

us o

n-lin

e flo

w m

onito

ring

of p

ipel

ine

inle

t and

out

let t

o id

entif

y m

ajor

leak

s.

Ant

i-sca

lant

and

bio

cide

dos

ing

will

be

cont

rolle

d to

pre

vent

ove

r dos

ing

Oil,

fuel

, che

mic

als o

r oth

er p

oten

tial p

ollu

tant

s w

ill b

e st

ored

and

tran

sfer

red

in b

unde

d ar

eas.

Dev

elop

and

mai

ntai

n co

ntin

genc

y pl

ans t

o ad

dres

s spi

lls.

All

was

tes w

ill b

e co

ntai

ned

in b

ins,

drum

s or i

n bu

nded

are

as w

here

nec

essa

ry a

nd d

ispo

sed

of

off-s

ite in

an

acce

ptab

le m

anne

r.

Neg

ligib

le im

pact

on

Gro

undw

ater

and

Mar

ine

wat

er a

nd se

dim

ent q

ualit

y.

Page 31: Upgrade of multi-user seawater supply and introduction of wastewater to ocean outfall ... · 2021. 1. 4. · The outfall diffuser for the brine discharge will be installed between

28

Envi

ronm

enta

lFa

ctor

sEP

A M

anag

emen

t Obj

ectiv

ePo

tent

ial I

mpa

ctPr

opos

ed M

anag

emen

t of R

elev

ant

Envi

ronm

enta

l Fac

tors

Pred

icte

d O

utco

mes

Soil

cont

amin

atio

nTo

ens

ure

that

no

cons

truc

tion

or

oper

atio

nal p

ract

ices

can

lead

to so

il co

ntam

inat

ion

Leak

age o

f sea

wat

er fr

om

the

pipe

line

thro

ugh

pipe

line

fittin

gs (e

g ai

r re

leas

e va

lves

) or p

ipel

ine

failu

res.

Cat

astro

phic

failu

re o

f pi

pelin

e ca

usin

g la

rge,

su

dden

rele

ase

of se

awat

er.

Dev

elop

com

preh

ensi

ve in

spec

tion

and

mai

nten

ance

pro

gram

for p

ipel

ines

and

fitti

ngs.

Seaw

ater

leak

s fro

m p

ipel

ine

fittin

gs w

ill b

e co

llect

ed in

per

man

ent s

umps

and

reco

vere

d w

ith p

orta

ble

pum

ping

equ

ipm

ent

Any

sco

ur se

awat

er w

ill b

e co

llect

ed a

nd

pum

ped

back

into

the

pipe

line

and

not a

llow

ed to

flo

w o

nto

the

grou

nd.

Con

tinuo

us o

n-lin

e flo

w m

onito

ring

of p

ipel

ine

inle

t and

out

let t

o id

entif

y m

ajor

leak

s.

Dev

elop

and

mai

ntai

n co

ntin

genc

y pl

ans t

o ad

dres

s spi

lls.

No

soil

cont

amin

atio

n w

ithin

pip

elin

e ea

sem

ents

Haz

eTo

ens

ure

that

em

issi

ons d

o no

t ca

use

incr

ease

d le

vels

of h

aze.

Bur

ning

of w

aste

s on-

site

may

cau

se u

nacc

epta

ble

leve

ls o

f haz

e.

No

burn

ing

of w

aste

s will

occ

ur o

n-si

te.

No

impa

ct o

n at

mos

pher

ic

(haz

e) c

ondi

tions

Noi

sePr

otec

t the

am

enity

of n

earb

y re

side

nts f

rom

noi

se im

pact

s re

sulti

ng fr

om a

ctiv

ities

ass

ocia

ted

with

the

prop

osal

by

ensu

ring

that

no

ise

leve

ls m

eet s

tatu

tory

re

quire

men

ts a

nd a

ccep

tabl

e st

anda

rds.

Ope

ratio

n of

the

pipe

lines

w

ill n

ot c

reat

e an

y no

ise

Con

stru

ctio

n pl

an to

iden

tify

pote

ntia

l noi

se

emitt

ing

activ

ities

and

ens

ure

com

plia

nce

with

En

viro

nmen

tal P

rote

ctio

n (N

oise

) Reg

ulat

ions

19

97.

Pote

ntia

l sm

all i

mpa

ct

durin

g co

nstru

ctio

n.

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29

Envi

ronm

enta

lFa

ctor

sEP

A M

anag

emen

t Obj

ectiv

ePo

tent

ial I

mpa

ctPr

opos

ed M

anag

emen

t of R

elev

ant

Envi

ronm

enta

l Fac

tors

Pred

icte

d O

utco

mes

SOC

IAL

SUR

RO

UN

DIN

GS

Vis

ual A

men

ityTo

ens

ure

visu

al a

men

ity o

f the

are

a ad

jace

nt to

the

proj

ect i

s not

und

uly

affe

cted

by

the

prop

osal

.

Con

stru

ctio

n ac

tiviti

es m

ay

redu

ce th

e vi

sual

am

enity

of

the

area

Dev

elop

men

t of c

onst

ruct

ion

plan

(s) t

o in

clud

e:•

min

imisi

ng a

rea

clea

red

• re

habi

litat

ion

of c

onst

ruct

ion

and

layd

own

area

s

No

long

-term

redu

ctio

n in

vi

sual

am

enity

Abo

rigin

al c

ultu

re

and

herit

age

To e

nsur

e th

at th

e pr

opos

al

com

plie

s with

the

requ

irem

ents

of

the

Abo

rigin

al H

erita

ge A

ct 1

972

and

that

cha

nges

to th

e bi

olog

ical

an

d ph

ysic

al e

nviro

nmen

t res

ultin

g fro

m th

e pr

ojec

t do

not a

dver

sely

af

fect

cul

tura

l ass

ocia

tions

with

the

area

.

The

com

plet

ed sc

hem

e w

ill

not c

ause

any

redu

ctio

n in

ab

orig

inal

cul

ture

and

he

ritag

e

Arc

haeo

logi

cal s

urve

y to

cle

arly

iden

tify

site

s of

cultu

ral s

igni

fican

ce w

ithin

con

stru

ctio

n ar

eas.

Con

stru

ctio

n pl

an to

iden

tify

avoi

danc

e or

re

loca

tion

of id

entif

ied

site

s.

Exis

ting

ease

men

ts a

nd ro

ad re

serv

es u

sed

for

pipe

line

alig

nmen

t pre

fere

ntia

lly.

No

disr

uptio

n to

Abo

rigin

al

cultu

re a

nd h

erita

ge.

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30

Appendix 4

Previous Statement of Conditions for this Proposal

Statement No. 567

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31

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32

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33

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34

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35

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36

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37

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38

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39

Figu

re 2

: Pi

pelin

e ro

ute

(Sou

rce:

Bur

ns &

Roe

Wor

ley,

Apr

il 20

01)

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40

Figu

re 3

: Des

alin

atio

n pl

ant g

ener

al a

rran

gem

ent (

Sour

ce:

Burn

s & R

oe W

orle

y, A

pril

2001

)

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41

Schedule 2

Proponent's Revised Consolidated Environmental Management Commitments

4 May 2001

DESALINATED WATER AND SEAWATER SUPPLIES PROJECT,BURRUP PENINSULA(Assessment No. 1378)

WATER CORPORATION

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42

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43

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44

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45

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46

Appendix 5

Recommended Environmental Statement to Amend Conditions

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47

Statement No.

RECOMMENDED ENVIRONMENTAL CONDITIONS

STATEMENT TO AMEND CONDITIONS APPLYING TO A PROPOSAL(PURSUANT TO THE PROVISIONS OF SECTION 46 OF THE

ENVIRONMENTAL PROTECTION ACT 1986)

DESALINATED WATER AND SEAWATER SUPPLIES PROJECTBURRUP PENINSULA, SHIRE OF ROEBOURNE

Proponent: Water Corporation

Proponent Address: 629 Newcastle Street, Leederville WA 6007

Assessment Number: 1419

Previous Assessment Number: 1378

Previous Statement Number: Statement No.567 (published on 22 June 2001).

Report of the Environmental Protection Authority: Bulletin 1044

Previous Report of the Environmental Protection Authority: Bulletin 1014

The implementation of this proposal to which the above reports of the Environmental Protection Authority relate is subject to the conditions and procedures contained in Ministerial Statement No. 567 (22 June 2001), as amended by the following:

Condition 2-1 (Proponent Commitments) of Statement No. 567 is deleted and the following condition is inserted:

2 Proponent Commitments 2-1 The proponent shall implement the revised consolidated environmental management

commitments of 19 March 2002 as documented in schedule 2 of this statement.

Note: The attached schedule 1 is inserted in place schedule 1 of 22 June 2001. Published on

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48

Schedule 1(Revised)

The Proposal (Assessment No. 1419)

The proposal is to construct and operate a seawater supply and desalination system to service the requirements of new industrial developments on the Burrup Peninsula, approximately 1,300kilometres north of Perth (Figure 1).

The proponent proposes to:

• Provide a seawater supply system with a capacity of approximately 280 megalitres per day;

• Provide a brine discharge into King Bay with a capacity of approximately 208 megalitres per day;

• Accept the discharge of treated industrial and domestic wastewater into the brine discharge stream from facilities that have environmental approval; and

• Construct and operate desalination plants on the Syntroleum Sweetwater Pty Ltd lease, the Burrup Fertilisers Pty Ltd lease and potentially other sites.

The pipeline route and location of the seawater inlet and brine outlet are shown in Figure 2 (attached). The main characteristics of the modified project are summarised in Table 1 below.

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49

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50

Figu

re 2

:Pi

pelin

e R

oute

(Sou

rce:

Bur

ns &

Roe

Wor

ley)

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51

Table 1: Summary of key proposed characteristics (Assessment No. 1419)

Element Description

Project Purpose To provide high purity water and seawater to industries on the Burrup Peninsula.Project Life 25 + yearsMajor Project Components

• Seawater supply pipelines (to 1.4m diameter)• 2 ML Seawater surge tank at the Three Sisters site• Brine discharge pipelines (to 1.1m diameter)• 2 ML brine break tank adjacent to Mermaid Marine, outfall pipe and diffuser array

into King Bay• 33 kV power line • Thermal desalination plant, including cooling tower, seawater storage tank and

desalinated water storage tank at the Syntroleum site• Thermal desalination plant , including seawater storage tank and desalinated water

storage tank at the Burrup Fertilisers site• Potentially, future desalination plants and associated infrastructure at other

developers sitesPlant Location • Seawater intake pump system � within the Mermaid Marine harbour development

• Seawater pipelines � within easements on the northern side of the mudflat north of Hearson Cove Road, eastern side of Burrup Road, northern side of King Bay Road and western side of the Mermaid Marine access road and property

• Brine pipelines � adjacent to seawater pipelines• 33 kV power line � adjacent to seawater and brine pipelines• Syntroleum Desalination plant � within the Syntroleum lease area, adjacent to the

process plant site, King Bay-Hearson Cove Industrial Area• Burrup Fertilisers Desalination plant � within the Burrup Fertilsers lease area,

adjacent to the process plant site, King Bay-Hearson Cove Industrial Area• Brine outfall and diffuser � extending approximately 800 m from the end of the

Mermaid Marine groyne to a point approximately midway between the Mermaid Marine and Woodside shipping channels at 4.0m CD.

Plant Operation Continuous � 24 hours per day, 365 days per year

Storage Capacities • Seawater service tank (Three Sisters site) - 2ML • Brine break tank (adjacent Mermaid Marine) - 2 ML • Syntroleum desalination plant seawater storage tank � 2 ML• Syntroleum desalination plant distilled water storage tank � 4 ML• Burrup Fertilisers desalination plant seawater storage tank � 2 ML• Future tanks at other developers sites

Inputs:

- Seawater Ultimately, 280 ML/d intake (including process cooling water)- Power Supply • Pump station � ultimately, approximately 3 MW, supplied from process plants

• Syntroleum Desalination Plant � approximately 1.5 MW supplied from Syntroleum• Burrup Fertilisers Desalination Plant � approximately 3 MW supplied from Burrup

Fertilisers• Potentially, other desalination plants at other developers sites

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52

Element Description

Discharges:- Brine Ultimately, approximately 208 ML/d at up to 55,000 mg/L TDS- Process wastewater Burrup Fertilisers � 0.8 ML/d

Potentially, similar quantities from other developers sites.- Domestic wastewater Burrup Fertilisers � 0.04 ML/d

Potentially, similar quantities from other developers sites.- Antiscalant Syntroleum desalination plant - 100 kg/d

Burrup Fertilisers desalination plant � 100 kg/dPotentially, similar quantities from other developers sites.

- Biocide Nil; decomposed by addition of sodium metabisulphite.- Sulphamic Acid Nil.- Temperature Discharge less than 5oC (less than 2oC for 80% of the time) above ambient seawater

temperature.- Heat Load Ultimately, approximately 208 ML/d nominally within 2°C of the ambient seawater

temperatureNoise:

- Construction: Less than 30 dB(A) at the nearest permanent residence (Dampier)- Operation: • Seawater intake system: Less than 70 dB(A) at 1m from pump well.

• Syntroleum Desalination plant: Less than 30 dB(A) at the nearest permanent residence (Dampier).

• Burrup Fertilisers Desalination plant: Less than 30 dB(A) at the nearest permanent residence (Dampier).

• Future desalination plants at other developers sites are likely to be very similar in nature and sound level at Dampier will be less than 30 dB(A).

Construction Period Approximately 20 monthsConstruction Workforce Peak 50Operational Workforce Estimated 6Project Benefit Provides a reliable, cost effective and environmentally sensitive water supply for industry

development on the Burrup Peninsula

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53

Schedule 2

Proponent's Revised Consolidated EnvironmentalManagement Commitments

19 March 2002

DESALINATED WATER AND SEAWATER SUPPLIES PROJECT

BURRUP PENINSULA, SHIRE OF ROEBOURNE (Assessment No. 1419)

WATER CORPORATION

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54

SUM

MA

RY

OF

MA

NA

GEM

ENT

CO

MM

ITM

ENTS

(Ass

essm

ent N

o. 1

419)

No

Topi

cA

ctio

nO

bjec

tive

Tim

ing

Adv

ice1

Terre

stria

l Flo

ra1)

Pre

pare

a w

eed

man

agem

ent p

lan.

2)

Impl

emen

t the

pla

n.To

pre

vent

the

intro

duct

ion

of n

ew w

eeds

.To

con

trol e

xist

ing

wee

ds.

Pre-

cons

truc

tion

Con

stru

ctio

nCA

LMA

gWA

(for

nox

ious

w

eeds

)2

Terr

estri

al F

lora

Con

duct

a d

etai

led

vege

tatio

n su

rvey

alo

ng th

e pi

pelin

e ro

ute

(incl

udin

g th

e Th

ree

Sist

ers

surg

e ta

nk),

in th

e ap

prop

riate

seas

on.

To id

entif

y an

d pr

otec

t sen

sitiv

e flo

ra.

Pre-

cons

truc

tion

CALM

3Te

rrestr

ial F

lora

1) P

repa

re a

flor

a an

d ve

geta

tion

plan

:•

to q

uant

ify a

rea

of v

eget

atio

n to

be

dist

urbe

d an

d th

e va

lues

tha

t w

ould

be

lost

.•

to s

et m

easu

res

to p

rote

ct s

igni

fican

t flo

ra a

nd v

eget

atio

n2)

Impl

emen

t the

pla

n.

To p

rote

ct si

gnifi

cant

, rar

e an

d en

dang

ered

flo

ra.

To p

rote

ct si

gnifi

cant

veg

etat

ion

asse

mbl

ages

.Pr

e-co

nstr

uctio

n

Con

stru

ctio

n

CALM

4Te

rrestr

ial F

lora

1) P

repa

re a

reha

bilit

atio

n m

anag

emen

t pla

n fo

r th

e co

nstru

ctio

n an

d la

ydow

n ar

eas:

to re

habi

litat

e di

stur

bed

area

s•

to m

onito

r veg

etat

ion

asse

mbl

ages

2) Im

plem

ent t

he p

lan.

To m

easu

re a

nd re

port

on re

habi

litat

ion

succ

ess.

Con

stru

ctio

n

Ann

ually

for 5

yea

rs,

then

bia

nnua

lly fo

r a

furth

er 1

0 ye

ars.

CALM

5Te

rres

trial

Fau

naC

onst

ruct

suita

ble

faun

a pa

ssag

es b

enea

th th

e ab

ove

grou

nd se

ctio

ns o

f the

pip

elin

es.

To p

rote

ct si

gnifi

cant

faun

a ha

bita

ts a

nd th

eir

acce

ss.

To p

rote

ct ra

re a

nd e

ndan

gere

d fa

una.

Con

stru

ctio

nCA

LM

6M

arin

eEn

viro

nmen

tal

Val

ues

Brin

e an

d w

aste

wat

er e

fflu

ent w

ill o

nly

be

acce

pted

from

indu

stria

l pro

cess

pla

nts:

1)fo

r whi

ch li

cenc

e an

d/or

Min

iste

rial

Con

ditio

ns (P

art I

V a

nd V

of t

he E

P A

ct)

have

bee

n is

sued

;2)

that

hav

e pr

ovid

ed a

ppro

pria

te to

xici

ty

and

envi

ronm

enta

l fat

e da

ta fo

r all

com

pone

nts o

f the

eff

luen

t to

the

satis

fact

ion

of th

e D

EP/E

PA; a

nd3)

whi

ch o

nly

utili

se D

EP/E

PA a

ppro

ved

proc

ess a

dditi

ves (

eg a

ntis

cala

nts,

cor

rosi

onin

hibi

tors

etc

).

To m

inim

ise

impa

cts o

n th

e m

arin

e en

viro

nmen

t

On-

goin

g

On-

goin

g

DEP

/EPA

CALM

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55

No

Topi

cA

ctio

nO

bjec

tive

Tim

ing

Adv

ice7

Mar

ine

Envi

ronm

enta

lV

alue

s

Con

tinue

to

revi

ew o

ptio

ns f

or r

ecyc

ling

and

reus

e of

br

ine

and/

or

was

tew

ater

ef

fluen

t(in

clud

ing

the

Dam

pier

Sa

lt op

tion)

.

The

infr

astru

ctur

e w

ill b

e de

sign

ed a

nd c

onst

ruct

ed

such

that

futu

re re

use

/ rec

yclin

g op

portu

nitie

s ca

n be

acc

omm

odat

ed.

To m

inim

ise

impa

cts o

n th

e m

arin

e an

d ge

nera

l en

viro

nmen

tO

n-go

ing

OM

PD

EP/E

PA

8M

arin

eEn

viro

nmen

tal

Val

ues

1)Pr

epar

e an

Env

ironm

enta

l Man

agem

ent P

lan

in c

onsu

ltatio

n w

ith t

he s

yste

m u

sers

and

th

e D

EP/E

PA.

The

plan

will

enco

mpa

ss:

• re

quire

men

ts fo

r mon

itorin

g (o

f eff

luen

t, se

awat

er, s

edim

ents

and

bio

ta);

• re

quire

men

ts fo

r ind

epen

dent

dat

a ve

rific

atio

n, e

valu

atio

n an

d re

porti

ng; a

nd•

mec

hani

sms f

or jo

int m

anag

emen

t of t

he

syst

em b

y th

e pr

opon

ent a

nd sy

stem

us

ers.

2)Im

plem

ent t

he p

lan.

To m

inim

ise

impa

cts o

n th

e va

lue

of th

e m

arin

e en

viro

nmen

tPr

e-co

mm

issi

onin

g

On-

goin

g

DEP

/EPA

CALM

9M

arin

e Fl

ora

and

Faun

aC

ondu

ct a

sur

vey

of th

e se

abed

to id

entif

y th

e m

arin

e ha

bita

ts a

nd b

enth

ic f

lora

and

fau

na

arou

nd th

e re

vise

d di

ffus

er lo

catio

n.

To p

rote

ct b

enth

ic fl

ora

and

faun

a.Pr

e-co

nstr

uctio

nCA

LMW

A M

useu

m

10M

arin

e Fl

ora

and

Faun

a1)

Pre

pare

a d

redg

ing

and

spoi

l di

spos

al p

lan

that

in

corp

orat

es

the

best

pr

actic

ally

avai

labl

e dr

edgi

ng

cons

truct

ion

met

hods

and

tech

niqu

es:

• to

min

imis

e ge

nera

tion

of tu

rbid

ity;

• to

min

imis

e re

dist

ribut

ion

of

cont

amin

ants

;•

to m

inim

ise

visu

al im

pact

s; a

nd•

to e

nsur

e se

awat

er o

xyge

n le

vels

are

no

t dep

lete

d.2)

Impl

emen

t the

pla

n.

To p

rote

ct a

nd m

inim

ise

the

exte

nt o

f di

stur

banc

e of

ben

thic

flor

a an

d fa

una.

Pre-

cons

truc

tion

Con

stru

ctio

n

DPA

DEP

/EPA

CALM

11M

arin

e Fl

ora

and

Faun

aIn

acc

orda

nce

with

the

Envi

ronm

enta

l M

anag

emen

t Pla

n m

onito

r em

issi

ons a

t the

ou

tfall

brea

k ta

nk:

• C

ontin

uous

on-

line

mon

itorin

g w

ill

incl

ude

at le

ast f

low

rate

, tem

pera

ture

, pH

, con

duct

ivity

, oxi

datio

n-re

duct

ion

To p

rote

ct se

ssile

flor

a an

d fa

una.

Pre-

com

mis

sion

ing

DEP

/EPA

Page 59: Upgrade of multi-user seawater supply and introduction of wastewater to ocean outfall ... · 2021. 1. 4. · The outfall diffuser for the brine discharge will be installed between

56

No

Topi

cA

ctio

nO

bjec

tive

Tim

ing

Adv

icepo

tent

ial,

amm

onia

and

turb

idity

.•

Oth

er c

onta

min

ants

that

can

be

reas

onab

ly a

nd re

liabl

y m

onito

red

by

on-li

ne in

strum

enta

tion

will

als

o be

m

onito

red.

• A

ppro

pria

te a

dditi

onal

mon

itorin

g w

ill

be c

ondu

cted

to q

uant

ify

disc

harg

e le

vels

of d

isso

lved

oxy

gen,

nut

rient

s,

proc

ess a

dditi

ves a

nd o

ther

en

viro

nmen

tal c

onta

min

ants

(suc

h as

he

avy

met

als)

in c

onsu

ltatio

n w

ith th

e D

EP/E

PA.

12M

arin

e Fl

ora

and

Faun

a1)

Brin

e em

issi

ons f

rom

Wat

er C

orpo

ratio

n de

salin

atio

n fa

cilit

ies s

hall

be c

ontro

lled

to

the

follo

win

g:•

Efflu

ent d

isch

arge

tem

pera

ture

to b

e le

ss th

an 2

0 C*

abov

e th

e in

let

seaw

ater

tem

pera

ture

for 8

0% o

f the

tim

e an

d no

t exc

eedi

ng a

max

imum

lim

it of

50 C

abo

ve, u

nles

s oth

erw

ise

agre

ed

with

the

DEP

.•

The

conc

entra

tion

of o

xidi

sing

bio

cide

in

the

efflu

ent d

isch

arge

to b

e le

ss

than

0.1

mg/

L.•

The

conc

entra

tion

of a

ntis

cala

nt in

the

efflu

ent d

isch

arge

to b

e le

ss th

an 2

m

g/L,

unl

ess o

ther

wis

e ag

reed

with

th

e D

EP.

2) T

he p

ropo

nent

, in

conj

unct

ion

with

syst

em

user

s, w

ill m

anag

e th

e to

tal e

fflu

ent

disc

harg

e to

mee

t the

abo

ve c

riter

ia.

To p

rote

ct se

ssile

flor

a an

d fa

una.

Ope

ratio

nD

EP/E

PA

13M

arin

e Fl

ora

and

Faun

aIn

acc

orda

nce

with

the

Envi

ronm

enta

l M

anag

emen

t Pla

n m

onito

r con

tam

inan

ts in

the

seaw

ater

, sed

imen

t and

bio

ta, t

hat i

nclu

des t

he

mon

itorin

g of

cag

ed �

sent

inel

� or

gani

sms

arou

nd th

e br

ine

outfa

ll.

Toes

tabl

ish

base

line

data

for t

he

conc

entra

tions

of h

eavy

met

als,

pro

cess

ch

emic

als a

nd o

ther

rele

vant

con

tam

inan

ts.

To id

entif

y lo

ng te

rm e

ffec

ts o

n bi

ota.

To p

rote

ct se

ssile

flor

a an

d fa

una.

Pre-

com

mis

sion

ing

On-

goin

g

DEP

/EPA

CALM

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57

No

Topi

cA

ctio

nO

bjec

tive

Tim

ing

Adv

ice14

Mar

ine

Flor

a an

d Fa

una

In a

ccor

danc

e w

ith th

e En

viro

nmen

tal

Man

agem

ent P

lan,

mon

itor s

eaw

ater

te

mpe

ratu

re a

t:•

the

inta

ke a

nd o

utfa

ll;

• ap

prop

riate

loca

tions

bet

wee

n th

e ou

tfall

and

the

near

est c

oral

co

mm

unity

; and

appr

opria

te re

fere

nce

loca

tions

.

To e

nsur

e no

adv

erse

impa

cts

on c

oral

co

mm

uniti

es p

artic

ular

ly th

e ne

ares

t cor

als t

o th

e di

scha

rge

diff

user

.To

ver

ify th

e di

sper

sion

mod

ellin

g re

sults

.To

inte

rpre

t the

resu

lts o

f any

cor

al m

onito

ring

prog

ram

.

On-

goin

g.(D

ecem

ber t

o A

pril,

fo

llow

ing

com

mis

sion

ing

of

each

add

ition

al p

lant

).

DEP

/EPA

CALM

15V

isua

l Am

enity

1) P

repa

re a

Vis

ual A

men

ity P

lan

that

incl

udes

:•

Mou

ndin

g of

exc

ess s

oil a

nd ro

ck to

fo

rm a

vis

ual s

cree

n w

here

pra

ctic

able

;•

Pain

ting

pipe

lines

in c

olou

rs th

at

blen

d w

ith th

e en

viro

nmen

t; an

d •

No

cons

truct

ion

of a

pip

elin

em

aint

enan

ce a

cces

s ro

ad, u

nles

s ot

herw

ise

agre

ed w

ith th

e D

EP.

2) Im

plem

ent t

he p

lan.

To p

rovi

de a

vis

ual s

cree

n of

the

pipe

lines

from

B

urru

p R

oad.

To

pre

vent

una

ccep

tabl

e vi

sual

impa

cts.

Pre-

cons

truc

tion

Con

stru

ctio

n

DEP

/EPA

16A

borig

inal

Her

itage

1) P

repa

re a

n A

borig

inal

Her

itage

Pla

n to

:•

iden

tify

all s

ites o

f cul

tura

l si

gnifi

canc

e;•

prov

ide

guid

elin

es fo

r avo

idan

ce o

f an

d be

havi

our a

roun

d si

tes;

and

• pr

ovid

e gu

idel

ines

if a

rtifa

cts a

re

foun

d.2)

Impl

emen

t the

pla

n.

To m

inim

ise

dist

urba

nce

to si

tes o

f cul

tura

l si

gnifi

canc

e.Pr

e-co

nstr

uctio

n

Con

stru

ctio

n

DIA

17R

isk

Des

alin

atio

n pl

ant d

esig

n an

d op

erat

ion

to b

e co

mpl

iant

with

the

Safe

ty R

epor

t and

Em

erge

ncy

Plan

of t

he p

roce

ss p

lant

(as

requ

ired

by th

e W

orks

afe

Nat

iona

l Sta

ndar

d fo

r th

e C

ontro

l of M

ajor

Haz

ard

Faci

litie

s).

To e

nsur

e sa

fe o

pera

tion

in p

roxi

mity

to a

maj

or

haza

rd fa

cilit

y.D

esig

n co

mpl

ianc

e -

pre-

cons

truct

ion.

Ope

ratio

n co

mpl

ianc

e �

prio

r to

oper

atio

n of

th

e pl

ant.

MPR

*The

diff

eren

ce b

etw

een

the

24 h

our a

vera

ge se

awat

er in

take

tem

pera

ture

and

the

brin

e di

scha

rge

tem

pera

ture

. A

gWA

= D

epar

tmen

t of A

gric

ultu

re W

este

rn A

ustra

liaC

ALM

= D

epar

tmen

t of C

onse

rvat

ion

and

Land

Man

agem

ent

DEP

= D

epar

tmen

t of E

nvir

onm

enta

l Pro

tect

ion

EPA

= E

nvir

onm

enta

l Pro

tect

ion

Aut

hori

tyD

IA =

Dep

artm

ent o

f Ind

igen

ous

Aff

airs

OM

P =

Off

ice

of M

ajor

Pro

ject

sM

PR =

Dep

artm

ent o

f Min

eral

and

Pet

role

um R

esou

rces

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58

Appendix 6

The Water Corporation�s Responsibilities in Managing the Multi-user

Brine and Wastewater Discharge System

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61

Appendix 7

Burrup Fertilisers� Proposed Discharge Criteria

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65