REPORT TO THE MINISTER FOR ENVIRONMENT...Appeals Convenor Environmental Protection Act 1986 REPORT...

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Appeals Convenor Environmental Protection Act 1986 REPORT TO THE MINISTER FOR ENVIRONMENT APPEAL IN OBJECTION TO THE CONDITIONS OF LICENCE L6593/1995/8, KEMERTON SILICA SAND MINE, LOT 32 ON DIAGRAM 63554 AND LOT 501 ON DIAGRAM 75016, RHODES ROAD, WOKALUP, SHIRE OF HARVEY PROPONENT: KEMERTON SILICA SANDS PTY LTD Appeal number 001 of 2013 December 2013

Transcript of REPORT TO THE MINISTER FOR ENVIRONMENT...Appeals Convenor Environmental Protection Act 1986 REPORT...

Appeals Convenor Environmental Protection Act 1986

REPORT TO THE MINISTER FOR ENVIRONMENT

APPEAL IN OBJECTION TO THE CONDITIONS OF LICENCE

L6593/1995/8, KEMERTON SILICA SAND MINE, LOT 32 ON DIAGRAM 63554 AND LOT 501 ON DIAGRAM 75016, RHODES ROAD,

WOKALUP, SHIRE OF HARVEY

PROPONENT: KEMERTON SILICA SANDS PTY LTD

Appeal number 001 of 2013

December 2013

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Appeal summary

This report relates an appeal lodged by Kemerton Silica Sands Pty Ltd (KSS) (the licensee) in objection to the Department of Environment Regulation (DER) (formally the Department of Environment and Conservation) conditions of Licence L6593/1995/8 (the licence). This report provides the Appeals Convenor’s recommendations to the Minister for Environment in respect to the appeal and is given under section 109(3) of the Environmental Protection Act 1986 (the EP Act). KSS operates a sand dredging mine approximately 35 kilometres north-east of Bunbury, where the main emission from the process is the discharge of ROM stacker overflow and process tailings into the dredge pond. Previously the licence required groundwater monitoring, however this has subsequently been removed to avoid duplication with the groundwater licence. Broadly the appellant’s concerns related to the new requirement to monitor discharge quantity and quality to the dredge pond, where for the first time DER also introduced targets and limits. In addition the appellant raised concerns regarding improvements requirements specified in the licence relating to Total Dissolved Salts. The appeal investigation has focused on the matters raised in the appeal and whether the conditions of the licence are adequate or appropriate to minimise, manage or abate emissions and discharges. Specifically the investigation has looked at the DER’s assessment of emissions and discharges using the emissions risk reduction matrix to determine whether limits and targets are required for the premises. Recommendation

For the reasons stated in this report, it is recommended that the appeal is upheld to the extent that the licence is modified as follows: 1. After a review of the assessment of emissions and discharges, the point source emission

limits to surface water are removed from the licence; 2. An exceedance of a target requires the licensee to undertake a management response; 3. Target values are reviewed after 12 months of actual monitoring data have been collected

and the licence amended where appropriate, including a review of the requirement for limits;

4. As recommended by the DER, the EC limits and targets are removed from Tables 2.3.2 and 2.3.3 in the licence (the licensee is not precluded from monitoring EC); and

5. As recommended by the DER, Condition 1.3.3, relating to pipelines, is removed from the licence.

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TABLE OF CONTENTS

INTRODUCTION .......................................................................................................... 1

BACKGROUND ........................................................................................................... 1

APPEALS PROCESS .................................................................................................. 2

GROUNDS OF APPEAL AND OUTCOMES SOUGHT ............................................... 3

GROUND 1 – ROM STACKER OVERFLOW .............................................................. 3

GROUND 2 – WATER QUALITY LIMITS .................................................................... 5

GROUND 3 – TARGET VALUES ................................................................................ 8

GROUND 4 – IMPROVEMENT REFERENCE ........................................................... 13

GROUND 5 – VOLUMETRIC FLOW RATE ............................................................... 15

GROUND 6 – PIPELINES .......................................................................................... 16

OFFICE OF THE EPA ADVICE ................................................................................. 16

CONSIDERATION AND RECOMMENDATION ......................................................... 18

CONCLUSION ........................................................................................................... 25

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INTRODUCTION This report relates an appeal lodged by Kemerton Silica Sands Pty Ltd (the licensee) in objection to the Department of Environment Regulation (DER) (formally the Department of Environment and Conservation) conditions of Licence L6593/1995/8 (the licence). This report provides the Appeals Convenor’s recommendations to the Minister for Environment in respect to the appeal and is given under section 109(3) of the Environmental Protection Act 1986 (the EP Act). BACKGROUND Kemerton Silica Sand Pty Ltd (KSS) operates a sand dredging mine approximately 35 kilometres (km) north-east of Bunbury (see Figure 1). The mining operation uses a suction cutter dredge, from which the sand slurry is pumped to a run-of-mine (ROM) storage area, where it is de-slimed and stockpiled. De-watered sand from the ROM stockpiles is fed into a processing plant where it is screened, washed and classified. The main emission from the process is the discharge of ROM stacker overflow and process tailings into the dredge pond. Water used for processing is abstracted under a groundwater well licence issued by the Department of Water (DoW). Figure 1: Premise location (adapted from whereis.com) The land contains regionally significant vegetation complexes and wetland flora and fauna, with some transferred to the State conservation system as offsets for mining extensions. The original mining proposal was subject to formal environmental assessment by the Environmental Protection Authority (EPA) and received Ministerial consent in 1994 (Statement 366). Subsequent proposals to extend the mine footprint were assessed by the EPA and are subject to Ministerial conditions (Statements 703 and 916). The mine was established under works approval 1232 and licensed under Part V of the EP Act in 1996. The latest licence, L6593/1995/8, was issued on 14 March 2013 and is the eighth issue (see Figure 2). The Office of the EPA, the DoW and the DER were involved in the assessment of the mine extension, and the DER reviewed the emissions and discharges from the mine under the Part V licence. The DER’s licence review determined that emissions and discharges to the dredge pond were not adequately regulated by the licence. Improvements in management techniques at the mine were identified to reduce the impact of total dissolved salts (TDS) in groundwater in the vicinity of the product stockpiles, and groundwater mounding in the zone of influence of the dredge pond on native vegetation. The DEC consulted with the DoW regarding the monitoring and management of ambient groundwater and sought to rationalise the monitoring requirements across the DoW groundwater licence, Part V licence and the Ministerial conditions.

The DER prepared a draft licence (issue 8) and discussed it with licensee’s representatives at a site meeting on 13 February 2013. The licence (issue 8) was advertised on 18 March 2013 and it is in relation to this licence that the appeal was received.

Premises

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Figure 2: Premise layout (source: Licence L6593/1995/8)

APPEALS PROCESS Pursuant to section 106 of the EP Act, a report was obtained from the DER on the matters raised in the appeal. Staff from the Office of the Appeals Convenor discussed the matters of concern with the appellant and also with the DER, the Office of the Environmental Protection Authority (EPA) and the DoW and conducted a site visit. The environmental appeals process is a merits based process. Appeal rights in relation to a licence are normally against the specifications of a licence, that is, whether the conditions of the licence are adequate or appropriate to minimise, manage or abate pollution and to ensure that premises are operated in an environmentally acceptable manner. As part of the appeals process the appellant requested a copy of the DER’s response to the appeal, in response the appellant provided additional information which has been included in this report. The Appeals Convenor has considered the additional information where necessary and appropriate.

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GROUNDS OF APPEAL AND OUTCOMES SOUGHT The appellant is seeking for the Minister to direct the DER to amend the licence as follows:

• Ground 1: Condition 2.3.1 – ROM stacker overflow: Outcome sought: Removal of the ROM stacker overflow point source from Table 2.3.1 and the plural ‘wastes’ from the description in condition 2.3.1.

• Ground 2: Condition 2.3.2 – Water quality limits: Outcome sought: Removal of the need to monitor point source discharges into the dredge pond from condition 2.3.2.

• Ground 3: Condition 2.3.3 – Target values: Outcome sought: Removal of, or amendments to, the target values in condition 2.3.3.

• Ground 4: Condition 4.1.2 – Improvement reference: Outcome sought: Removal of Improvement Reference 1R2 from Table 4.1.1.

• Ground 5: Condition 3.3.1 – Volumetric flow rate: Outcome sought: Removal of the requirement to monitor volumetric flow rate from Table 3.3.1.

• Ground 6: Condition 1.3.3 – Pipelines. Outcome sought: Removal of Condition 1.3.3.

The appellant’s submissions in support of the above grounds are detailed below, followed by the Appeals Convenor’s consideration and recommendations. GROUND 1 – ROM STACKER OVERFLOW The appellant highlighted that Condition 2.3.1 states that the licensee is permitted, subjected to conditions in the licence, to emit wastes to surface water from the emission point listed in Table 2.3.1. The appellant considered that the ROM stacker overflow point source outlined in Table 2.3.1 has been wrongly classified as a waste, as overflow from the ROM stacker is returned to the dredge pond as a way to manage excess moisture from the interim ore storage area at the processing plant. The appellant advised that the discharge pipe for this material into the active dredge pond is specifically positioned in an area which will be subsequently dredged; therefore the ROM stacker overflow is not a waste. The appellant sought the removal of the ROM stacker overflow point source from Table 2.3.1. DER advice The DER advised that that the dredge pond is a source of the ore body, a source of process water (the dredge pond intersects the shallow groundwater table) and a facility for storing and recycling that water. The DER stated that the dredge pond also receives process tailings, dewatering effluent from ore and product stockpiles (referred to as ‘ROM stacker overflow’), and other process intermediates and wastes, such as oversize and slimes. The DER considered that the material entering the dredge pond is a blend of ore that is intended to be recovered through subsequent dredging, water that will be recycled in the process, and solid and liquid wastes. The DER considered that these wastes are, in part, comprised of materials that are kinds of waste prescribed in Schedule 4, Part 2 of the Environmental Protection Regulations 1987, namely tailings and water to allow for mining of ore.

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The DER stated that the ROM stacker overflow originates from the dredge pond and is a mixture of groundwater, rainfall and recycled process water that is returned to the dredge pond as excess process water or dewatering effluent. The DER noted that in correspondence accompanying the appeal, the ROM stacker overflow is described as excess moisture from the ore storage area at the process plant. The DER advised that this is consistent with its determination that the ROM stacker overflow is effluent from product dewatering. The DER noted that the appellant’s Groundwater Monitoring Summary described the return of coarse tailings and thickened slimes to the dredge pond, along with ROM stacker overflow, and refers to ‘the return of all waste streams to the dredge pond’. The DER considered that this was also consistent with DER’s determination that the ROM stacker overflow is a waste, and is contrary with the appellant’s statement. If this material was fully recovered and re-used in the process, the DER advised that it would not consider it to be a waste. The DER considered that discharging this material into the dredge pond causes a proportion of the material to infiltrate the superficial aquifer, with potential impact on groundwater quality, therefore it is deemed to be a discharge into the environment. The DER noted that the appellant’s Groundwater Monitoring Summary stated that there is a return of all waste streams to the dredge pond at an average flow of approximately 800,000 kL/year, while the groundwater extraction for the annual review period was 93,708 kL. Based on this information, the DER considered that the following was unclear:

• The proportion of the waste streams are solid or liquid components and what proportion of the waste streams returned to the dredge pond are being re-circulated; and

• The proportion of the water returned to the dredge pond that infiltrates the superficial aquifer.

The DER advised that the monitoring of the groundwater bores around the dredge pond shows a clear trend of increasing salinity, which could be attributed to the infiltration of higher salinity water from the dredge pond. The DER advised that it does support the re-use of water from the dredge pond in the mining operations, and co-disposal of solid and liquid wastes into the dredge pond consistent with the requirements of the Ministerial Statements applied to the premises. Additional advice from the appellant The appellant noted that the DER considered that the ROM stacker overflow is, in part, ‘water to allow for mining of ore’ as stated in Schedule 4, Part 2 of the Environmental Protection Regulations 1987. The appellant acknowledged that this is the case, and therefore conceded that technically under this definition the ROM stacker overflow is a waste. The appellant also acknowledged that discharging the ROM stacker overflow into the dredge pond is an indirect discharge to the environment as the dredge pond does intercept the superficial aquifer. The appellant noted that the DER considered that it was unclear what proportion of the waste streams are solid or liquid components and the proportion being re-circulated and what proportion of the water returned to the dredge pond infiltrates the superficial aquifer. The appellant advised that the volume of the ROM stacker overflow is estimated to be less than 0.5% of the total dredge pond water volume at any one time (the area of the current dredge pond is 16 hectares) and that impact of the ROM stacker overflow on groundwater quality is likely to be negligible. The appellant advised that the 11 groundwater monitoring bores and two production bores are measured for groundwater level on a monthly basis and groundwater quality on a quarterly basis, to assess the impact of the mining operation on the superficial aquifer. The appellant advised that the annual Groundwater Monitoring Summary prepared by Rockwater and submitted to the DoW and DER, assessed the impact of the mining operation on the groundwater environment. The appellant advised that a letter from the DoW stating

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acknowledgement of submission of the 2012 annual report (dated 19 September 2012) concluded ‘Monitoring data presented in the report show no water level or water quality trends or conditions that are likely to be having an unacceptable affect on the aquifer or other users.’ The appellant noted that the DER advised that ‘Monitoring of the groundwater bores around the dredge pond shows a clear trend of increasing salinity, which could be attributed to the infiltration of higher salinity water from the dredge pond.’ The appellant requested evidence for this statement as the groundwater monitoring and the DoW suggest there is no basis for this conclusion. The appellant challenged the DER’s reason for monitoring the ROM stacker overflow pipe as a point source emission which is discharging to the environment. The appellant believed that the dredge pond is the area of interaction with the environment, and thus it should be continued to be monitored as it has been since the project commenced. The appellant maintained that the ROM stacker overflow should be removed from Table 2.3.1 of the licence as it is not a point of emission into the environment. The appellant considered that monitoring of the dredge pond is a more appropriate location to determine impacts on the environment. GROUND 2 – WATER QUALITY LIMITS The appellant referred to Condition 2.3.2, that the licensee shall not cause or allow point source emissions to surface water greater than the limits in Table 2.3.2. The appellant challenged the relevance of water quality limits on the surface water parameters as the point source emissions discharge into an active dredge pond, not natural surface water. The appellant advised that both the plant tailings and ROM stacker overflow have only undergone physical treatment via a cyclone since removal from the dredge pond with no chemicals added during production of the final silica sand product. The appellant considered that the ‘waste’ materials as defined by the DER, are being returned to the place of removal as is required by conditions of Ministerial Statement 366. The appellant also challenged surface water quality limits to point source discharges into an operational dredge pond that has no direct linkage to surface waters in the local area. The appellant noted that the decision report accompanying the licence stated that a review of past water quality data was used in determining limits and targets, with the aim of reducing water quality impacts from the premises. The appellant advised that the water quality data referred to by the DER was dredge pond Total Dissolved Salts (TDS) data from 2001 to 2008 reported in the 2012 Groundwater Monitoring Summary and attached to the Annual Monitoring Report submitted to the DER in October 2012. The appellant advised that this is not the full data set that has been collected over 12 years. The appellant questioned the need to monitor point source discharges to the active dredge pond given that monitoring data provided to the Environmental Protection Authority (EPA), DER and DoW demonstrates it has not negatively impacted water quality beyond the premises that was not permitted by Ministerial Statement 366. DER advice The DER advised that limits on the discharge into the dredge pond have been set for the first time in this licence and the limits in the draft licence were presented to, and discussed with the appellant at a meeting on 13 February 2013, and no objections were raised at that time. The DER advised that the DoW officers described the dredge pond as a short-term surface expression of the groundwater table where it has been intersected by the excavation of the dredge pond. Inflows to the dredge pond act to recharge the groundwater table, and the quality of water entering the dredge pond could influence the groundwater quality down-gradient from the dredge pond. The DER advised that discharges from processing operations

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are therefore considered to be a discharge to the environment and require regulation under Part V of the EP Act. The DER concurred that the dredge pond is ‘surface water’, for the purposes of the licence issued under the EP Act and that the DER’s licences are structured in sections that distinguish between discharges to air, surface water, groundwater, land, and fugitive emissions. The DER considered that the distinction between surface water and groundwater is academic. The DER advised that the dredge pond is comprised of water which is in continuity with environmental water at the premises, including groundwater and a surface water body formed as a modified, short-term surface expression of that groundwater. Having regard for the definitions for groundwater and surface water provided by the National Water Commission, the DER determined that it was appropriate to consider the dredge pond as ’surface water’, while acknowledging that the dredge pond is formed from, and constitutes, a direct hydraulic connection to the groundwater. The DER considered that the dredge pond constitutes ‘the environment’ on the basis that:

a) the water in the pond has a direct hydraulic connection with the groundwater that comprises the superficial aquifer in the area; and

b) at the completion of mining, rehabilitation of the pond will result in a permanent surface water body or wetland at the site.

The DER stated that it understood that the monitoring bores located around the processing plant and the dredge pond are indicating a steady increase in TDS and this was discussed with the appellant at the 13 February 2013 meeting. The DER advised that both the DoW and DER have concluded in its response to the s45C expansion at the premises that there does appear to be an impact on groundwater quality at the premises. The DER advised that prior to the issues of this licence, the appellant was not required to actively monitor the quality or quantity of the discharge into the dredge pond. Given that this is the primary emission into the environment from the process and that the latest review of information has identified a risk of negative impact on groundwater, the DER considered it appropriate to require monitoring of this discharge to ensure that discharge quality is within environmentally acceptable levels. The DER considered this approach to be consistent with the then Department of Environment’s (DoE) Limits and Targets for Prescribed Premises Policy (April, 2006). Additional advice from the appellant The appellant advised that it has monitored the dredge pond since 2001 as it was required under the groundwater licence, in 2008 this requirement was removed as a licence condition; however the appellant advised that it continued to voluntarily monitor the dredge pond. The appellant agreed with the DER in that any potential impacts need to be within environmentally acceptable limits; however the appellant considered that those recently set in the licence do not appear to be based on the pre-mining environment, monitoring results to date or regional information, and as such the appellant rejected the application of limits on this facility. The appellant advised that the DER presented the preliminary draft licence at the meeting on 13 February 2013 and whilst it did not have sufficient time to review the preliminary draft licence in detail during the meeting, limits were discussed and reasons for the proposed significant licence changes sought. The appellant stated that it subsequently reviewed the preliminary draft licence and provided comments to DER on 7 March 2013 and exchanged e-mails with the DER discussing the proposed numerical limits and targets.

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The appellant noted that the DER stated the ‘Inflows to the dredge pond act to recharge the groundwater table and the quality of the water entering the dredge pond could influence the groundwater quality down-gradient from the dredge pond.’ The appellant disagreed with this statement on the basis that inflows to the dredge pond act to fill the dredge pond. The appellant considered that the dredge pond that interacts with the groundwater and could influence groundwater quality; therefore the dredge pond should be monitored as a discharge to the environment, and thus requires regulation under Part V of the Act. The appellant did not understand why the DER wants to monitor the two discharge pipes and not the dredge pond, and was unsure what benefit there would be in introducing the requirement to now monitor the discharge pipes considering there is 16 years’ worth of dredge pond data already available. The appellant noted that the DER licences are structured in a certain way, so a discharge must fit a category so it can be effectively licensed. The appellant asserted that the DER is trying to fit the dredging activity into a licence structure that does not cater for, to the extent that, that the distinction between surface water and groundwater is academic. The appellant considered that to be illogical and does not provide a practical solution to protecting the groundwater environment in the Kemerton area. The appellant agreed with DER’s account of the dredge pond that the dredge pond comprises water which is in continuity with environmental water at the premises, including groundwater and a surface water body formed as a modified, short term expression of that groundwater. The appellant advised that the current dredge pond was created in 2010 and if the DER considered it appropriate to require monitoring of this discharge to ensure that discharge quality is within environmental acceptable levels, the appellant recommended comparing the dredge pond quality to other surface water bodies on, or near, the KSS premises that are also hydraulically connected to the groundwater. The appellant suggested Lake 1 (the initial dredge pond when the operation commenced which is still being monitored) created in 2006, or Environmental Protection (Swan Coastal Plain Lakes) Policy 1992 (EPP) wetlands which are now in the Kemerton Nature Reserve. The appellant advised that the dredge pond moves location once the sand has been dredged; earlier mined areas to the immediate north-east of the current dredge pond have been closed off to form three reconstructed lakes and are currently being rehabilitated. The appellant stated that these lakes no longer receive any mine water and are maintained through natural groundwater inflow and rainfall and are located between the current dredge pond and the Kemerton Nature Reserve. The appellant advised that Chart 1 shows the TDS in the current dredge pond and Lake 1 compared to rainfall, where it can be seen that there is considerable seasonal variation in TDS results which largely reflect rainfall trends. The appellant highlighted that the TDS is higher in Lake 1 compared to the dredge pond. Given the dredge pond regularly receives inflows from KMB7 via the plant, the appellant considered that the impacts of evapotranspiration can reasonably be expected to be lower compare to Lake 1. The appellant objected to the DER’s comment that the DoW and the DER have concluded in response to the s45C expansion at that there does appear to be an impact on groundwater quality at the premises. The appellant advised that it has not prepared a Section 45 C and assumed that the DER refer to the PER for the mine extension that was approved by the Minister of Environment in November 2012 under MS 916.

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The appellant advised that the EPA’s Report 1425 (January 2012) stated:

• Groundwater quality - acid sulphate soils and metalliferous drainage - is one of the key environmental factors relevant to the proposal and these will be managed through the implementation of specific management plans when the extension commences so that there are no impacts on the ecological values of the EPPs (wetlands) (EPA Report 1425, 2012); and

• The DER’s Contaminated Sites Branch considered the risk of ASS disturbance to be low, but that soil and groundwater quality data indicate there is a regional acidification problem (EPA Report 1425, 2012).

The appellant considered that these factors do not appear to have been taken into account as part of the recent environmental licence review process. GROUND 3 – TARGET VALUES The appellant referred to Condition 2.3.3 which states that the licensee shall target point source emissions to surface water at or below the levels specified in Table 2.3.3. The appellant believed this condition to be flawed for two main reasons:

• As raised under Appeal Ground 2, the appellant challenged why the materials discharged into the dredge pond require targets. The appellant referred to the decision report which stated that targets are currently based on current environmental values and will be revised pending the outcome of Improvement Reference 2 (IR2) into ambient groundwater quality. The appellant stated that the quality of the water being discharged into the dredge pond to be within current environmental values which do fluctuate naturally; and

• The appellant considered that the actual numerical values for limits and targets documented in the licence to be technically flawed and highlighted that there have been considerable discussion with the DER since February 2013 regarding the limit and target values and the application to the dredge pond. Therefore if there is a need for limits and targets on the water quality monitoring for the dredge pond emissions, the appellant considered that these need to be valid and relevant to the operation.

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The appellant noted that Table 2.3.2 lists the limit values for the water quality parameters, where the pH limit range is 5.5 to 8.5 based on 3 standard deviations from the mean for existing water quality data from the discharge to the dredge. The appellant advised that while there has never been monitoring conducted on the actual discharges to the dredge pond, there has been voluntarily monitoring the pH in the dredge pond on a monthly basis since 2009, where mean pH is 6.14. On this basis the appellant calculated the pH limit range to be 4.2 to 8.1 if three standard deviations from the mean are used. The appellant considered that the limit and target values for Total Acidity and Total Alkalinity in Table 2.3.2 and Table 2.3.3 were not evidenced based, as these parameters have not been monitored before. The appellant considered that it would be beneficial to have a basis for these if they have been established on local environmental values as stated in the DER’s report. The appellant also suggest stating the upper and lower limit and target for these parameters in Tables 2.3.2 and 2.3.3. The appellant was of the view that the unit for the limits and targets for Total Acidity and Total Alkalinity listed in Table 2.3.2 and Table 2.3.3 are unsuitable, as the unit needs to be more descriptive and recommend using calcium carbonate (CaCO3) to pH 8.3 to measure both Total Acidity and Total Alkalinity. The appellant considered that the target values for Electrical Conductivity (EC) and TDS in Table 2.3.3 are not directly correlated and therefore technically incorrect, for example EC 1,400 μS/cm and TDS 600 mg/L are not directly correlated. The appellant suggested that the TDS target needs to be 840 mg/L as a target of 600 mg/L is not relevant for the dredge pond. The appellant advised that this value has been exceeded 45 times since 2009 and there is no evidence to suggest this has resulted in any environmental harm to the local Kemerton or surrounding areas. The appellant advised that variability in TDS results are known to be more directly linked to climatic events i.e., lower EC and TDS concentrations after rainfall and higher TDS values during prolonged dry periods which have been experienced in more recent years. DER advice In accordance with the then DoE’s Limits and Targets for Prescribed Premises Policy, the DER considered that it is appropriate to set a limit and require compliance monitoring for emissions likely to fall between 50 to 110% of an ambient environmental standard or guideline. In this case, the DER considered it appropriate to include emission targets, consistent with ambient environmental criteria, which the appellant had met previously and should be able to achieve under most circumstances. The DER advised that these target levels are set to trigger a management response where the expected levels are not achieved to minimise the impact on the environment. Based on a review of the 2011 and 2012 dredge pond water quality data, the DER advised that the pond has higher salinity levels than the ambient groundwater quality in bores that are not directly influenced by mining operations (i.e. bores other than those located near the dredge pond, the processing plant and product stockpiles). Higher salinity levels in bores located near the dredge pond and processing areas are considered by the DER to be influenced by the mining process, which is concentrating salinity, possibly through evaporative processes, and infiltrating back into the superficial aquifer via the dredge pond. The DER advised that the ‘current environmental values’ referred to by the appellant related to water quality in the dredge pond, which is affected by the mining process. As stated in the Decision Document of the licence, the DER advised that it based discharge quality criteria on ‘current environmental values’ which should be interpreted to refer to ambient groundwater quality in monitoring bores that have not been impacted by mining processes.

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The DER considered that the argument that the water entering the dredge pond is consistent with the water in the dredge pond is a circular one and does not negate the requirement for the appellant to minimise the impact of discharges on the receiving environment. The DER considered that the dredge pond water quality is having an impact on the groundwater aquifer quality. Referring to the Decision Document, the DER advised that the limits and targets are based on, not prescribed as, three and one standard deviations from the mean. The pH limit range selected (5.5 to 8.5) is based on the recommended trigger levels for dewatering effluent, as per the guidance document Treatment and management of soils and water in acid sulfate soil landscapes (DEC, July 2011). The DER advised that the shallow groundwater at the premises is already showing signs of acidifying, and is highly vulnerable to acidification. The DER therefore considered it inappropriate to set limit values consistent with three standard deviations as calculated (4.2 to 8.1) in this instance. The DER advised that the values adopted for Total Alkalinity and Total Acidity were not based on local environmental values as asserted by the appellant. The DER stated that they were based on the guidance document Treatment and management of soils and water in acid sulfate soil landscapes, which provides an outline of the expected minimum trigger levels, corrective actions and associated monitoring for dewatering effluent in acid sulfate soil landscapes. The DER advised that in consultation with the DoW, it has set limits and targets on the dewatering discharge, which are based on the guideline trigger levels. The DER acknowledged that these parameters have not been monitored before at the premises, however, as stated in the Decision Document, these values will be reviewed after 12 months of actual monitoring data have been collected. The DER noted that the appellant considered that the unit specified for the analysis of Total Acidity and Total Alkalinity needs to be more descriptive, and recommends using calcium carbonate at pH 8.3. The DER advised that it does not object to the use of this method, and the licence only requires that samples are submitted to a laboratory with current National Association of Testing Authorities, Australia accreditation for the parameters to be measured. The DER considered that the analytical method did not have to be prescribed in the licence in this instance. The DER advised that the selection of a numerical target for TDS in the dredge pond was based on discussions with the DoW, which advised that a TDS concentration of 500 mg/L is desirable for the long-term protection of the water resources in the local groundwater area. The DER considered that the data from the appellant indicated that this value has been exceeded on 45 occasions since 2009 and justifies the requirement for this target in the licence. The DER stated that the salinity of groundwater in the vicinity of the dredge pond is increasing over time and, therefore, management actions are required to mitigate this environmental impact. The DER highlighted that exceeding a licence target level does not constitute a breach of the licence; however it triggers management review and action. In the example the appellant described, the DER advised that increases in groundwater salinity resulting directly from factors such as prolonged dry periods, suggests that management review could be to make appropriate conclusions related to seasonal fluctuation, based on objective assessment of the monitoring data. The DER accepted that the EC target value of 1,600 µS/cm does not correlate with the target TDS of 600 mg/L. The DER advised that this was an error in the conversion of TDS to EC which was not corrected in the final licence. After further consideration, the DER accepted that salinity is adequately monitored through TDS and recommended that targets and limits for EC are removed from the licence.

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The DER highlighted that the rationale used for determining limits and targets, while standardised through published policy, has been summarised in the Decision Document. The DER advised that the Decision Document does not fully describe the complete analysis that was undertaken in comparing multiple water quality parameters from multiple monitoring locations, to various environmental quality standards. The DER considered that this brevity may have contributed to misinterpretation by the appellant of the methods used by the DER to set limits and targets on a range of environmental quality objectives. The DER recommended that this ground of appeal be allowed to the extent that the EC limits and targets are removed from Tables 2.3.2 and 2.3.3 in the licence. Additional advice from the appellant The appellant advised that the mining activities at the premises were approved under MS 366 and it was understood some impacts to surrounding water quality would occur, however the EMP (and other management plans) was developed to ensure impacts were managed appropriately. The appellant advised that the DER is licensing a project whose impacts have been formally assessed and approved by the Minister for the Environment under MS 366, which includes reporting requirements. The appellant noted that the DER had based discharge quality criteria on current environmental values, interpreted to refer to ambient groundwater quality in monitoring bores that have not been impacted by mining processes. The appellant restated its position that the discharges into the dredge pond should not be compared to groundwater quality that is not impacted by surface influences or mining (i.e. monitoring bores KMB1 and KMB2). By its physical location, the appellant asserted that surface water and groundwater in the Kemerton area will have different characteristics, where surface water quality is strongly influenced by evapotranspiration and rainfall whereas groundwater is less influenced by these factors. The appellant advised that Chart 2 shows the TDS of KMB1, KMB2 and the dredge pond, where it is apparent that licence conditions will be continually breached (which has occurred in April and May) as the TDS in the dredge pond is considerable higher than in KMB1 and KMB2.

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The appellant advised the following regarding local groundwater:

• Monitoring bores KMB1 and KMB2 are upstream from the mining operation and are located closer to the western edge of the property which is near to the recharge area of the Mialla Mound and thus has fresher groundwater (<500 mg/L);

• Locally shallow groundwater flow is dominated by the Mialla Mound, a significant recharge area located over the Spearwood Dune system. Greater transmissivity and hydraulic conductivity in the Spearwood Dune sands facilitates natural recharge and creation of the Mialla Mound;

• Groundwater flow is both east and west away from the mound and groundwater is observed to discharge in low lying areas on either side of the mound, resulting in natural wetland and swamp systems;

• Shallow groundwater quality is generally fresh to brackish although in local discharge areas salinity can be as high as 20,000 mg/L TDS;

• Groundwater salinity generally increases in the direction of groundwater flow, but significant local variations have been observed due to differences in permeability, local recharge (irrigation and mine surface water bodies), evapotranspiration and leakage from clays;

• Naturally high acidity levels (< pH 5 with some seasonal fluctuations) have been present in KMB6 and KMB10 since monitoring commenced and it is possible that low pH groundwater could flow naturally beneath the dredge pond and seep into the pond if the head of the water is below the water table; and

• According to a report by GHD in 2008, groundwater in the area is characterised by relatively low pH and low salinity levels. However, a study by Rockwater in 2007 indicted that down-gradient zones contain relatively brackish (1,500 mg/L to 3,000 mg/L TDS) groundwater (Impact Assessment of Mining on Groundwater, GHD, May 2008).

The appellant noted that target values have been set based on the broad values in the guidance document Treatment and management of soils and water in acid sulfate soil landscapes (DEC, 2011). Although not stated explicitly, the appellant advised that this document has been developed from fresh water quality guidelines based on the Australian and New Zealand Environment and Conservation Council (ANZECC and ARMCANZ, 2000) methodology. The appellant considered that ANZECC (2000) methodology supports the development of site specific site based trigger levels over default values that are not site specific presented in guidance documents. Therefore the appellant recommended that any trigger values that should be applied to the dredge pond be based on the several years of surface water monitoring data already available and which allows flexibility in application due to the seasonal variation in the local environment. The appellant did not support the removal of the EC parameter as a consequence of inaccurate calculation of values in the licence. The appellant advised that it will continue to monitor EC in the dredge pond as it provides a more accurate measure of potential impact of salinity than TDS. In addition, the appellant noted that TDS values are not referenced in the fresh water quality guidelines in the Australian and New Zealand Guidelines for Fresh and Marine Water Quality (ANZECC and ARMCANZ 2000) which is the guidance document used by DER and the appellant. If a trigger value needs to be applied to EC monitoring in the dredge pond, the appellant recommended basing it on the several years of data already available as shown in Chart 3. The appellant considered that the monitoring data shows EC in Lake 1 is consistently higher, although similarly seasonal, when compared to the dredge pond, where both these water bodies have increasing salinities as rainfall and runoff reduces and effects from evapotranspiration increases, even though only the dredge pond receives mining discharges.

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The appellant recommended using an EC limit value of 1,755 μS/cm, calculated using three standard deviations from the mean, and a target value of 1,435 μS/cm which is one standard deviation from the mean.

GROUND 4 – IMPROVEMENT REFERENCE The appellant referred to Condition 4.1.2, that the licensee, for improvements not specifically requiring a written submission, shall write to the Director stating whether and how the licensee is compliant with the improvement within one week of the completion date specified in Table 4.1.1. The appellant considered that the improvement reference 2 (IR2) in Table 4.1.1 states that the licensee shall submit to the Director a report that assesses the concentration of TDS in ROM stacker overflow being discharged to the dredge pond against ambient groundwater quality. The appellant challenged the requirement to assess the ROM stacker overflow against groundwater quality criteria when it is discharged to an active dredge pond which the DER has previously classified in the licence as surface water. The appellant advised that the ROM stacker overflow water quality is not anticipated to differ from the dredge pond water quality given it undergoes nothing but separation via a cyclone at the ROM pad and is returned to the dredge pond in less than one hour from the time it was removed by the dredge. The appellant further advised that the volume of the ROM stacker overflow is estimated to be less than 0.5% of the total dredge pond water volume at any time and the ROM stacker overflow pipe only discharges for approximately 120 days each year on average, and thus, its impact on groundwater quality is likely to be negligible. The appellant stated that the DER has already been provided with dredge pond water quality information and there have not been water quality issues that have necessitated any government department requesting investigations into impacts on surface or groundwater quality. Therefore the appellant questioned the need for and relevance of such an investigation referred to as IR2.

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DER advice The DER noted that this ground of appeal refers to Condition 4.1.2, which requires an assessment of TDS concentration in the ROM stacker overflow to the dredge pond against ambient groundwater quality. The DER advised that a report on the assessment is required to include a program of improvements to reduce TDS levels, where it does not conform to the ambient groundwater quality, the report is to be submitted by 1 November 2013 (Table 4.1.1 IR2). As detailed in Grounds 1 and 2 above, the DER advised that the dredge pond intersects the shallow groundwater table which is considered by both the DER and the DoW to be a surface expression of that groundwater table. The DER considered that the water quality in the dredge pond has been demonstrably altered by the mining activity. The DER advised that the dredge pond has direct hydraulic connection to the groundwater of the superficial aquifer, which in turn appears to be showing increased salinity and decreased pH as a result of the infiltration of water from the dredge pond. As detailed above, the DER determined that these observed changes in water quality are a result of the mining process and have become apparent after several years of operations at the premises. The DER considered that this condition is reasonable and needed to further assess the potential impact of the dredge pond on the aquifer, and gives the appellant an opportunity to review its operations and submit proposals for improvements if they are necessary. Additional advice from the appellant The appellant noted that the DER response to appeal correctly stated that the dredge pond intersects the shallow groundwater table and water quality in the dredge pond has been demonstrably altered by mining activity. However, the appellant also noted that it then stated that the superficial aquifer appears to be showing increased salinity and decreased pH as a result of the infiltration of water from the dredge pond. The appellant considered that there is no evidence of this occurring and the DER has inaccurately ‘determined that these observed changes in water quality (of the superficial aquifer) are a result of the mining process’. The appellant referred to a letter from the DoW (19/09/2012) stating acknowledgement of the 2012 Groundwater Monitoring Summary concluded ‘Monitoring data presented in the report show no water level or water quality trends or conditions that are likely to be having an unacceptable affect on the aquifer or other users.’ Furthermore, the appellant advised that it has recently provided the Hydrogeological Review required by Condition 4.1.2 in Table 4.1.1 of the licence to the Director of DER (dated 31 May 2013). The Hydrogeological Review provided an assessment of groundwater within the zone of influence of seepage from the dredge pond and concluded:

• The current dredge pond is more saline than the surrounding shallow groundwater and that the surface water is very gradually becoming more saline due to both reduced inflows of groundwater and rainfall, and effects of evapo-concentration;

• There is little to no evidence of significant seepage from the dredge pond into the surrounding superficial aquifer; and

• There is no direct correlation between dredge pond water quality and nearby shallow groundwater quality.

The appellant referred to the opinion of the DoW and the Hydrogeological Review required by Condition 4.1.2 to be sufficient in providing information that the dredge pond is not impacting the ambient groundwater quality, and therefore considered that 1R2 in Table 4.1.1 was not necessary. Similar to Appeal Ground 3, the appellant rejected the assessment of ambient groundwater quality being monitoring results from KMB1 and KMB2 as explained Ground 3 above, as

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these groundwater bores are closer to the freshwater recharge area of the groundwater and thus not relevant to groundwater nearer the dredge pond. Again the appellant requested the DER to provide evidence of the perceived negative impact from the dredge pond on the aquifer. GROUND 5 – VOLUMETRIC FLOW RATE The appellant noted that Condition 3.3.1 requires the licensee to undertake the monitoring in Table 3.3.1 according to the specifications in that table. The appellant questioned the requirement to monitor volumetric flow rate of the ROM stacker overflow and tailings pipe into the dredge pond on a monthly basis. The appellant advised that the flow rate is part of the closed circuit pumping to and from the plant and therefore considered that the information is not useful for production purposes and is unlikely to be useful for environmental monitoring purposes. The appellant stated that the project has operated successfully for 17 years without recording such information and challenges the need to do so now. DER advice In response, the DER advised that the effective management and assessment of waste discharged to the environment requires an accurate understanding of the amount of waste discharged. To quantify the amount, the DER considered that it is important to know the volume of the discharge; in particular, the information will inform the assessment under Condition 4.1.2 (IR2) and help in assessing any trends in the discharge quality and ambient quality. The DER further advised that the monitoring of volumetric flow rate is a standard licence requirement where waste is discharged into the environment and is applied widely in licences across a range of industries, including mining. Additional advice from the appellant The appellant did not agree that effective management of the environment requires an accurate understanding of the amount of waste discharged into the dredge pond. The appellant asserted that the level of water in the dredge pond is maintained to operate the dredge and the closed circuit pumping to and from the plant, notwithstanding evaporation and run-off into the dredge pond. The appellant noted that Condition 1.3.2 of the licence now requires the dredge pond to be managed by ensuring:

a) a minimum top of embankment freeboard of 500 mm is maintained; b) overtopping does not occur except as a result of an extreme rainfall event and c) groundwater mounding is less than 1 metre from standing ground level.

The appellant was of the view that condition 1.3.2, together with the following provided effective management of the environment and the requirement to measure the volumetric flow rate of the pipelines is superfluous:

• Daily inspections of the residue pipelines and embankment freeboard required by Condition 1.3.4 of the licence;

• Monitoring of the dredge pond;

• Groundwater monitoring required by the groundwater licence;

• Implementation of three management plans required under MS 366; and

• Annual reporting to the regulators.

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GROUND 6 – PIPELINES The appellant considered that Condition 1.3.3 should be removed as it is impractical, serves no real purpose to prevent environmental harm and would potentially negatively impact native vegetation. The appellant advised that it has investigated the use of automatic cut-outs and considered that it is not practical for this project, as in the event the pipes are automatically cut off the whole plant will shut down, where discharge will back up and need to be flushed through the system into the dredge pond. The appellant advised that the flow rate through the pipes varies as a part of normal operations, and as such it will be problematic to install and set an automatic cut off when flow rate decreases. The appellant advised that it has also investigated installation of secondary containment for the ROM overflow pipe and the tailings pipe since the site visit by DER in February 2013. The appellant further advised that the pipes do not contain hazardous material, only sand water slurry and some of the route is located in an area authorised to be mined in the near future. In order for the containment bunds to be installed, the appellant stated that vegetation clearing and disturbed and clearing would be required. In the 17 years of mining activity, the appellant asserted that there has never been a tailings or ROM stacker overflow pipe failure that has negatively impacted the vegetation, soil, surface or groundwater and therefore it questions the need to retroactively install bunding for pipes that do not contain or transfer hazardous materials. DER advice The DER advised that the intent of the condition requiring that pipes are automatically cut-off is that in the event of a leak from the process overflow or tailings pipelines, materials do not continue to be pumped. The DER considered that this would minimise the discharge into the environment and prevent an uncontrolled discharge at an unauthorised location. During DER’s site visit on 13 February 2013, the DER was of the view that process material and wastes were not adequately contained by either the infrastructure or the procedures in place. The DER advised that the licence holder was unable to demonstrate the full route of either pipeline or the preventative measures in place to ensure that uncontrolled discharge of process materials does not occur. The DER considered the argument that vegetation scheduled to be cleared for mining should not be disturbed not to be a valid one, however, the DER accepted equally that process overflow and tailings discharge in these areas does not represent significant environmental impacts as there is no need to protect this vegetation from impacts of uncontrolled discharges. The DER recommended that this ground of appeal be allowed on the basis that daily visual inspections of pipelines and infrastructure specified under licence condition 1.3.4 is adequate to manage the risk of discharge of piped materials in areas scheduled to be disturbed by mining. OFFICE OF THE EPA ADVICE As the appellant had broadly raised in its appeal potential duplication with Part IV of the EP Act, with the licence requirements the advice of the EPA was sought. The Office of the EPA advised the following: 1. The Ministerial Statements that apply to the Kemerton Silica Sand Mine operated by

Kemerton Silica Sands Pty Ltd (KSS) are 366, 703, 916, and 920. These were issued under Section 45(7) of Part IV of the EP Act. The proposals related to statements 703, 916 and 920 are yet to commence.

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2. In accordance with Ministerial Statement 366, KSS is required to prepare and implement a Groundwater Monitoring and Management Programme (GWMMP) (Conditions 5-1 and 5-2 of MS 366), in consultation with the DoW and the Department of Parks and Wildlife (DPaW). Statement 366 also requires an Environmental Management Programme (EMP) addressing surface water and groundwater management. The appellant provided the plans (GWMMP and EMP) for groundwater and surface water management in 1998. Updated versions of GWMMP (revised as Wetland Monitoring Management Plan, WMMP) and EMP were submitted to the Office of the EPA in December 2012. The OEPA has received advice from DoW and DPaW on these revisions and are under review to ensure that the monitoring regimes adequately protect ecosystem values.

3. The Ministerial Statement 366 required quarterly monitoring of the surface water levels of

the unmined lakes in the project area covered by the Environmental Protection (Swan Coastal Plain Lakes) Policy 1992). Groundwater levels are required to be monitored monthly and chemical analyses of groundwater is to be performed at least once a year. The monitoring required by the Part IV is mainly focused on surface and groundwater levels whereas the Part V licence requires monitoring of water quality of the emissions to the dredge pond from discharge pipes. The monitoring required by DER under Part V is therefore considered to complement the requirements of Part IV by providing water quality data to indicate where potential impacts to surface water and groundwater may have originated.

Groundwater quality and level monitoring requirements are also addressed in the groundwater licence issued by DoW under the Rights in Water and Irrigation Act 1914 (RIWI Act). After consultation with the DoW, it has been agreed that to avoid duplication, groundwater quality and level monitoring will not be included in the EMP.

4. The OEPA are currently reviewing the updated WMMP and EMP and will request a

resubmission of these plans. Improvements for the management and protection of surface water and groundwater under the Part IV of EP act have been identified. While these improvements have not been finalised at this time, some of the suggestions by the OEPA are as follow: a) All the seven unmined EPP lakes must be monitored as opposed to only EPP lakes 4

and 7 proposed by the KSS as the protection of all seven wetlands from impacts associated with the project is required by Condition 5 of Ministerial Statement 366.

b) Sections 7.3 and 7.4 of the EMP should clearly indicate that groundwater quality and level monitoring requirements (activity, frequency and target) are being addressed in the groundwater licence issued by the DoW under the RIWI Act.

c) In accordance with Condition 5-2 of MS 366, KSS must ensure adequate groundwater level monitoring and understanding of the interactions between the deeper aquifer zone and the water table, wetland, GOEs, water quality changes in the shallow aquifer zone close to the water table. The GMMP therefore, should include a discussion about whether the new shallow and deep groundwater bores will enable KSS to develop the understanding of the relationships discussed above.

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CONSIDERATION AND RECOMMENDATION By the appeal, the appellant challenged the requirement to monitor discharges (ROM stacker overflow) into the dredge pond, the introduction of limits and targets on the discharges and the improvement requirements relating to TDS. Previous licences only required monitoring of groundwater, where limits and targets did not apply. The appellant also considered that there may be duplication of monitoring requirements with Part IV of the EP Act. ROM stacker overflow The appellant believed that the ROM stacker overflow point source outlined in Table 2.3.1 has been wrongly classified as a waste, as overflow from the ROM stacker is returned to the dredge pond as a way to manage excess moisture from the interim ore storage area at the processing plant. Through its appeal the appellant sought the removal of the ROM stacker overflow point source from Table 2.3.1 and considered that the dredge pond is a more appropriate location to determine impacts on the environment. It is noted that Condition 2.3.1 states:

The DER advised that the material entering the dredge pond is a blend of ore that is intended to be recovered through subsequent dredging, water that will be recycled in the process, and solid and liquid wastes. The DER considered that these wastes are, in part, comprised of materials that are kinds of waste prescribed in Schedule 4, Part 2 of the Environmental Protection Regulations 1987, namely tailings and water to allow for mining of ore. In its additional advice the appellant conceded that technically under this definition the ROM stacker overflow is a waste. The ROM stacker overflow originates from the dredge pond and is a mixture of groundwater, rainfall and recycled process water that is returned to the dredge pond as excess process water or dewatering effluent. If this material was fully recovered and re-used in the process, the DER advised that it would not consider it to be a waste. However, the DER considered that discharging this material into the dredge pond causes a proportion of the material to infiltrate the superficial aquifer, with potential impact on groundwater quality; therefore it is deemed to be a discharge into the environment. The DER considered that the dredge pond constitutes ‘the environment’ on the basis that:

• the water in the dredge pond has a direct hydraulic connection with the groundwater that comprises the superficial aquifer in the area; and

• at the completion of mining, rehabilitation of the pond will result in a permanent surface water body or wetland at the site.

Therefore based on the advice of the DER it is considered that the ROM stacker overflow is a discharge into the environment it is recommended that this ground of the appeal be dismissed. It is also noted that the DER supports the re-use of water from the dredge pond in the mining operations, and co-disposal of solid and liquid wastes into the dredge pond.

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Volumetric flow rate The appellant questioned the requirement to monitor volumetric flow rate of the ROM stacker overflow and tailings pipe into the dredge pond on a monthly basis as required by Condition 3.3.1 which states:

The appellant considered that the information would be useful for production purposes and is unlikely to be useful for environmental monitoring purposes. The appellant was of the view that Condition 1.3.2 and 1.3.4 and the monitoring required under Part IV of the EP Act and the groundwater licence provided effective management of the environment and the requirement to measure the volumetric flow rate of the pipelines is superfluous. In response the DER advised that the effective management and assessment of waste discharged to the environment requires an accurate understanding of the amount of waste discharged. To quantify the amount, the DER considered that it is important to know the volume of the discharge, in particular, the information will inform the assessment under condition IR2 and help in assessing any trends in the discharge quality and ambient quality. Consistent with the advice of the DER it is considered that there is merit in assessing the volumetric flow rates to inform investigations required under the licence, also noting that the DER advised that monitoring of volumetric flow rate is a standard licence requirement. Therefore it is recommended that this ground of the appeal be dismissed. Pipelines The appellant considered that Condition 1.3.3 should be removed on the basis that is it impractical and serves no real purpose to prevent environmental harm and would potentially negatively impact native vegetation. It is noted that the condition states:

It is noted that the appellant investigated the use of automatic cut-outs and considered that it was not practical for this project, as in the event the pipes are automatically cut off the whole plant would shut down. The appellant also advised that the pipes do not contain hazardous material, only sand water slurry and some of the route is located in an area authorised to be mined in the near future. In response the DER advised that the intent of the condition requiring that pipes are automatically cut-off is that in the event of a leak from the process overflow or tailings pipelines, materials do not continue to be pumped. The DER considered that this would minimise the discharge into the environment and prevent an uncontrolled discharge at an unauthorised location.

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The DER accepted that process overflow and tailings discharge in these areas does not represent significant environmental impact as there is no need to protect this vegetation from impacts of uncontrolled discharges. The DER recommended that this ground of appeal be allowed on the basis that daily visual inspections of pipelines and infrastructure specified under Condition 1.3.4 is adequate to manage the risk of discharge of piped materials in areas scheduled to be disturbed by mining. On this basis and consistent with the advice of the DER it is recommended that this ground of the appeal be allowed to the extent that Condition 1.3.3 is removed from the licence. Water Quality Limits and Targets The appellant broadly challenged the rational for applying targets and limits to the premises under Condition 2.3.2 and Condition 2.3.3, which state the following:

The previous licence for the premises required monitoring of groundwater for standing water level, pH and TDS. This licence does not require monitoring of groundwater as the DER and the Office of the EPA advised that this will now be required as part of a DoW licence. However for the first time under the licence the appellant is required to monitor discharges into the dredge pond (hydraulically linked to groundwater), where both targets and limits apply. The DER considered that overall there is evidence that groundwater is acidifying, indicating a pH decrease and an increase in salinity. The appellant objected to these assertions and considered there is no impact to the groundwater. Therefore the question of whether there is an impact to groundwater quality remains disputed. The groundwater quality report (Rockwater, 2012) did include historical data for groundwater; however the raw data was not interpreted for the purpose of this appeal. The report (Rockwater, 2012) indicated that in 2011 to 2012 the groundwater monitoring bores salinity varied from 90 to 950 mg/L TDS and the pH ranged from 3.6 to 8.4. The DER advised that on the basis of impacts to groundwater it introduced limits and targets onto the licence for the tailings and the ROM stacker overflow, which it considered is consistent with the Limits and Targets for Prescribed Premises Policy (April, 2006).

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The DoE (2006) Policy statement for Limits and Targets for Prescribed Premises advises:

There are essentially three ways to determine whether an emission is significant enough to warrant the imposition of a limit:

1. An emission standard has been imposed through an EPA policy or required by a Ministerial condition or appeal decision.

2. Comparison with an emission standard.

3. Comparison with an ambient standard or guideline using forward modelling of the emission. Once it has been determined that a limit is required, it may be set using the following in order of preference:

1. Set the emission standard that has been imposed through an EPA policy or required by a Ministerial condition or appeal decision.

2. Apply an emission standard.

3. Set the limit such that the ambient standard or guideline is achieved (as verified from forward modelling of the emission).

Therefore in assessing the premises it is noted that the Decision Table in the licence states the following with regard to point source emissions to surface water including monitoring:

Referring to the risk matrix (Appendix A) the DER found:

• The Emission Significance – 3

• Socio-political Context – Some community interest or concern Based on the above, the DER assessment found the point source emissions to surface water including monitoring to be at ‘B = licence condition (setting limits + EMPs – short timeframes)(setting targets optional)’. With regard to the socio-political context, it is not clear how the socio-political context was determined to be ‘some community interest or concern’. The DER report advised that no comments were received from the public during the advertisement and the report does not provide rational regarding the nearest residence or local interest. Other decisions in the decision table of the Decision Report list the Socio-political context as ‘No Concern or Interest’.

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In order to clarify the basis of the socio-political context as discussed above, further advice from the DER was sought. The DER advised:

The rationale used to establish the socio-political risk assessment rating of 'Some community interest or concern' drew upon emissions experienced by the community and subsequently expressed as complaints to DER, and interest raised or concerns expressed to DER. In these circumstances, individuals or community members who live adjacent to, or are neighbours of the prescribed premises may experience a full range of impacts from the prescribed premises' discharges or emissions. DER is cognizant of the generally limited scientific knowledge currently available regarding the impact of emissions and discharges. Where reasonable uncertainty exists about the impact that emissions and discharges from prescribed premises are having upon nearby individuals (as demonstrated by complaints and community interest), the regulatory approach to the emission or discharge should include additional control measures. This approach is completely consistent with the "precautionary principle" set out in section 4A of the EP Act and generally accepted worldwide in environmental regulation. This principle is embedded in the risk assessment decision-making matrix and executed under the Policy statement: Limits and targets for prescribed premises. To establish the level of community concern for each prescribed premises emission a rating system is used. This can be ascertained by determining the number and nature of complaints, submissions by the community and Ministerial correspondence or regulator concerns received over a defined period of time relating to the emission and classifying this information into various ratings from 'No interest or concern' to 'significant level of community interest or concern'. DER assessed the Kemerton Silica Sands operations surface water emissions to be in direct connectivity with groundwater which has 'some interest or concern' to other agencies such as DoW, Office of Environmental Protection Authority, Department of Parks and Wildlife, LandCorp as land manager of Kemerton Industrial Estate, Department of State Development, South West Development Commission, Shire of Harvey and other surface/groundwater users in the locality including horticulturalists, self-supply users, stock water users and public drinking water sources for Binningup and Myalup.

While the DER highlighted that there is interest from other government agencies regarding groundwater, including EPA and the DoW that have a regulatory role, it is noted that there is no evidence of complaints, interests or concerns from the community. In view of the above, is recommended that the socio-political context is amended to ‘No Concern or Interest’, which is considered to reflect the information in the DER’s Decision Report. On this basis and by using the emissions risk reduction matrix (Table 5, Appendix A) the assessment would be C (Priority Matrix Action Descriptors), which requires licence condition (setting targets + EMPs – longer timeframes). Therefore consistent with this approach, it is recommended that the point source emissions limits to surface water are removed from the licence, however the targets should remain. It is recommended that after a period of at least 12 months, the DER review the data from the point source emissions against groundwater quality to determine whether limits are required in the future. The appellant also contended that the DER had not considered the full data set that has been collected over 12 years in determining targets and limits, only data from 2001 to 2008. Specifically the appellant challenged the basis of the numerical values documented in the licence. In response, the DER advised that the limits and targets are based on:

• pH: limit range selected (5.5 to 8.5) as per the guidance document Treatment and management of soils and water in acid sulfate soil landscapes (DEC, July 2011);

• Total Alkalinity and Total Acidity: Targets and limits were based on the guidance document Treatment and management of soils and water in acid sulfate soil landscapes;

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• Total Alkalinity and Total Acidity (units): The DER noted that the appellant considered that the unit specified for the analysis of total acidity and total alkalinity needs to be more descriptive, and recommends using calcium carbonate at pH 8.3. The DER advised that it does not object to the use of this method, and the licence only requires that samples are submitted to a laboratory with current National Association of Testing Authorities, Australia accreditation for the parameters to be measured;

• TDS: TDS was based on discussions with the DoW, which advised that a TDS concentration of 500 mg/L is desirable for the long-term protection of the water resources in the local groundwater area; and

• EC: The DER accepted that the EC target value of 1,600 µS/cm does not correlate with the target TDS of 600 mg/L. The DER recommended that targets and limits for EC are removed from the licence.

The DER acknowledged that these parameters have not been monitored before at the premises, however, as stated in the Decision Document, the DER advised that these values will be reviewed after 12 months of actual monitoring data have been collected. Noting the above, the DER have advised that it has set the targets and limits selected for pH and total alkalinity and total acidity based on established guidelines. However, with regard to TDS targets, it is noted that they have been based on advice from the DoW regarding groundwater quality, not an emission standard or ambient guideline. Therefore, it is recommended that the target value for TDS is reviewed after 12 months of actual monitoring data has been collected and any known impacts to groundwater quality for TDS would be more clearly known. In addition, it is noted that the breach of a target in this licence does not trigger a reporting requirement to the DER. Consistent with the DoE (2006) Policy Statement: Limits and targets for prescribed premises it is recommend that the licence is amended so that the exceedance of a target requires a management response. Monitoring required by the EPA The appellant broadly asserted that the requirements of the licence replicate the reporting required by the EPA under Part IV of the EP Act. Therefore in this regard it is noted that Ministerial Statement 366 requires:

• GWMMP;

• EMP;

• quarterly monitoring of the surface water levels of the unmined lakes in the project area covered by the Environmental Protection (Swan Coastal Plain Lakes) Policy 1992; and

• Groundwater levels are monitored monthly and chemical analyses of groundwater is to be performed at least once a year.

In summary, the Office of the EPA considered that the monitoring required under Part V complements the requirements of Part IV by providing water quality data to indicate where potential impacts to surface water and groundwater may have originated. Improvement reference The appellant challenged the requirement to assess the ROM stacker overflow against groundwater quality criteria as required by IR2 in Condition 4.1.2 on the basis that:

• ROM stacker overflow water quality is not anticipated to differ from the dredge pond water quality;

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• the volume of the ROM stacker overflow is estimated to be less than 0.5% of the total dredge pond water volume therefore its impact on groundwater quality is likely to be negligible; and

• The DER has already been provided with dredge pond water quality information and there have not been water quality issues that have necessitated any government department requesting investigations into impacts on surface or groundwater quality.

Condition 4.1.2, states:

As noted above, Condition 4.1.2 required 1R2 to be submitted to the DER on 1 November 2013. The proponent confirmed with the Office of the Appeals Convenor on 4 November 2013 that this had been submitted to DER. Therefore, as the date of completion for IR2 has passed, this ground of the appeal will not be considered further. Other Matters Notwithstanding the appellant’s objection to the application of targets and limits, subsequent to the appeal the appellant also challenged the relevance of water quality targets and limits on the point source emissions. The appellant asserted that the chemical characteristics of the dredge pond, tailings and ROM stacker overflow would have similar characteristics, and therefore monitoring of the dredge pond was sufficient. The appellant also considered that the monitoring of the dredge pond would be more informative for determining the potential impacts to groundwater than monitoring the ROM stacker overflow and the tailings. The appellant provided the data it has collected for the ROM stacker overflow and tailings pipeline since the new licence has been in force, from April to August 2013, which indicated that chemical characteristic of the ROM stacker overflow are different to those of the tailings pipeline and the dredge pond, especially with regards to Total Acidity. With regard to the need to monitor the ROM stacker overflow, it is considered that the characteristics of the ROM stacker overflow are not the same as the dredge pond and the tailings as asserted by the appellant. Therefore to further understand discharges at the premises it is considered that the DER was justified in requiring the licensee to monitor the ROM stacker overflow and the tailings. Discussions with the DoW and the DER indicate there was some concern regarding the methods used to sample the dredging pond and the certainty around the results. Therefore it is considered that the monitoring of discharges would provide data to clarify whether the operation is potentially having an impact on groundwater and the source of any impact. The Office of the EPA also advised that the requirements of the licence compliment

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the requirements of Part IV of the EP Act in determining whether there are potential impacts to the EPP wetlands. CONCLUSION The Kemerton Silica Sands Mine has been operating for over 15 years and has been subject to formal assessment by the EPA. In March 2013 the DER issued licence L6593/1995/8, which is the subject of this appeal. Broadly the appellant challenged the requirement to monitor discharges (ROM stacker overflow and tailings) into the dredge pond, the introduction of limits and targets on the discharges and the improvement requirements relating to TDS. Previous licences only required monitoring of groundwater, where limits and targets did not apply. The EPA and the DoW have advised that groundwater monitoring is addressed in the groundwater licence issued by DoW under the RIWI Act. The appeal investigation has focused on the matters raised in the appeal and whether the conditions of the licence are adequate or appropriate to minimise, manage or abate emissions and discharges. Specifically the investigation has looked at the DER’s assessment of emissions and discharges using the emissions risk reduction matrix to determine whether limits and targets are required for the premises. It follows that, for the reasons stated in this report, it is recommended that the appeal is upheld to the extent that the licence is modified as follows: 1. After a review of the assessment of emissions and discharges, the point source emission

limits to surface water are removed from the licence; 2. An exceedance of a target requires the licensee to undertake a management response; 3. Target values are reviewed after 12 months of actual monitoring data have been collected

and the licence amended where appropriate, including a review of the requirement for limits;

4. As recommended by the DER, the EC limits and targets are removed from Tables 2.3.2 and 2.3.3 in the licence (the licensee is not precluded from monitoring EC);

5. As recommended by the DER, Condition 1.3.3, relating to pipelines, is removed from the licence.

In addition, and consistent with the advice of the DER, it is recommended that target values are reviewed after 12 months of actual monitoring data have been collected and the licence amended where appropriate. It is recommended that the review also looks at the future requirement for limits. It is noted that there is some remaining disagreement between the appellant and the DER regarding ambient groundwater quality and impacts to groundwater quality as a result of the operation. It is anticipated that the monitoring of discharges and the investigations required under the licence will assist to clarify these matters. Kelly Faulkner APPEALS CONVENOR Report prepared by: Lorna Davies, Senior Environmental Officer

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References

Department of Environment (2006). Policy Statement: Limits and Targets for Prescribed Premises. Rockwater (2012) Kemerton Silica Sand Pty Ltd. Groundwater Monitoring Summary July 2011 to June 2012 GWL 60367(3). Report for Kemerton Silica Sand Pty Ltd, August 2012.

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Appendix A: Emissions and discharges risk assessment matrix (source: Licence L6593/1995/8