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Prepared for: Tasmanian Advanced Minerals Date: November 2012 Rev 00

Supplement Environmental Effects Report Calder Waste Silica Depot

pitt&sherry ref: HB11206H001 rep 31P Rev 00/JL/mn

Table of Contents 1. Introduction ............................................................................................... 1 2. EPA Summary Table of Representations ............................................................. 1 3. Report Format ............................................................................................ 1 4. Submission #1 ............................................................................................. 2

4.1 Dust ................................................................................................ 2 4.2 Noise ............................................................................................... 2

5. Submission #2 ............................................................................................. 3 5.1 Dust ................................................................................................ 3 5.2 Water Quality .................................................................................... 3

6. Submission #3 ............................................................................................. 4 6.1 Dust ................................................................................................ 4 6.2 Land Contamination ............................................................................. 4

7. Submission #4 ............................................................................................. 5 7.1 Dust ................................................................................................ 5 7.2 Groundwater ..................................................................................... 5

8. Submission #5 ............................................................................................. 6 8.1 Dust ................................................................................................ 6

9. Submission #6 ............................................................................................. 7 9.1 Groundwater ..................................................................................... 7 9.2 Dust ................................................................................................ 7 9.3 Noise ............................................................................................... 7 9.4 Flora ............................................................................................... 7

10. Submission #7 ............................................................................................. 8 10.1 Material Properties .............................................................................. 8 10.2 Landfill Design ................................................................................... 8 10.3 Water Quality .................................................................................... 9 10.4 Groundwater ..................................................................................... 9 10.5 Flora and Fauna .................................................................................. 9 10.6 Noise ............................................................................................. 10 10.7 Dust .............................................................................................. 10 10.8 Transport ........................................................................................ 10 10.9 Risk Assessment/Contingency Plans ........................................................ 10 10.10 Rehabilitation/Revegetation ................................................................ 11 10.11 Heritage ......................................................................................... 12

11. Submission #8 ........................................................................................... 13 11.1 Dust .............................................................................................. 13 11.2 Noise ............................................................................................. 13

12. Planning .................................................................................................. 14 12.1 Traffic ........................................................................................... 14 12.2 Land use ......................................................................................... 14 12.3 Security .......................................................................................... 14 12.4 Fire Fighting .................................................................................... 14

13. General................................................................................................... 15 13.1 Traffic ........................................................................................... 15 13.2 Responsibility................................................................................... 15 13.3 OHS ............................................................................................... 15 13.4 Document ....................................................................................... 15 13.5 Reporting ........................................................................................ 15

14. EPA Divisional Request ................................................................................ 16 15. Management Commitments .......................................................................... 17

Appendix A EPA Summary of Representations

Appendix B Closest Residences to Depot and Calder Intersection

Appendix C Residential Properties on Transport Routes

Appendix D Predicted Surface and Groundwater Drainage Path

pitt&sherry ref: HB11206H001 rep 31P Rev 00/JL/mn 1

1. Introduction Tasmanian Advanced Minerals (TAM) submitted a development application, DA 116/2012, to the Waratah Wynyard Council (WWC) on the 3 September 2012 for a waste silica depot located off Calder Road near Calder in northern Tasmania. The application was supported by an Environmental Effects Report drafted according to the Environment Protection Authority (EPA) guidelines and directives. Following advertising of the proposal by WWC, eight representations were received and these were forwarded by the WWC to the EPA for consideration in the environmental assessment of the proposal. On 20 November 2012, the EPA requested that a supplement to the EER be drafted to address the comments in the representations and assist the completion of the EPA environmental assessment. The representations were summarised by the EPA into a table, and the table forms the scope of this supplement.

2. EPA Summary Table of Representations The EPA summary table defines the scope of the EER supplement and the format of the EER. The EPA summary table of the public and agency representations and comments is contained in Appendix A. The environmental issues raised are addressed in the same order as the submission numbers shown in the EPA table.

3. Report Format The sections of the supplement are based on the EPA summary table. The supplement sectional formatting is outlined below:

Section 1 - Introduction

Section 2 - EPA Summary Table of Representations

Section 3 – Report Format

Section 4 - Submission #1








Section 12 – Planning

Section 13 – General

Section 14 – EPA Division Request

Section 15 - Commitments

Appendices.


4. Submission #1

4.1 Dust Dust emissions as a result of vehicle movements along Calder Road on route to the site, including on site access will be covered by the existing permits and management practices for transport to Heybridge. These practices and their regulations will continue. It is expected that the depot permit will include similar conditions to those that currently apply. The relevant environmental conditions in the Waratah-Wynyard DA 170/2005-A permit for the Wynyard processing plant are conditions A1, A2, A3, A4, G3 and Schedule 3. Calder Road is sealed and road dust will not be an issue. Any potential dust from the internal access road will come from the existing road paving material. Road dusting will be minimised by tanker watering during hot dry windy weather. The separation distances between the waste depot traffic and residences will be the same as already exists for current traffic movements on Calder Road and the Hanson quarry access road. Refer to figures 2 and 3 and section 7.5 of the EER and the details in Appendix B. The nearest residence is approximately 600 m from the proposed waste depot site. The separation distances between waste depot site and the closest identified residences are shown on the map in Appendix B.

4.2 Noise The noise from additional traffic movements on Calder Road will be negligible compared to that which already exists. Currently there are approximately 1,670 traffic movements per day on Calder Road (information courtesy of DIER) of which a reasonable proportion are heavy vehicles. The nominal 3 - 4 truck loads per day and maximum 10 truck loads per day will not affect the current noise levels. The waste trucks are well maintained and relatively modern in design and comply with Australian transport design criteria. The designated depot site is located on a worked out area of the Hanson Construction Materials (Hanson) mining lease. No noise issues or complaints have been recorded by the EPA from this activity. The noise levels associated with the waste depot are predicted to be less than those emitted during the extraction operations. The closest residences are shown on the map contained in Appendix B. There have been no known noise complaints associated with the 674 residences located along the current route to Heybridge. There have been no known noise complaints associated with the 102 residences located along the Calder Road route for the Hanson quarry operations. No complaints are envisaged for the proposed waste transport along Calder Road. Refer to section 7.8 of the EER. The residential information is courtesy of the LIST © State of Tasmania (Cadastre, Transport). Refer to Appendix C for details.


5. Submission #2

5.1 Dust The risk of health impact from dust emissions are assessed as being negligible. This is based on the proposed depot design, management plans, performance requirements and avoidance and mitigation measures outlined in section 7.5 of the EER. The onsite OHS requirements, mitigation measures and validation monitoring will ensure that the OHS risks are negligible. The achievement of OHS requirements will ensure negligible risk to public health.

5.2 Water Quality The discharge of sediment from the depot to the Inglis River will be negligible. Surface water and depot under drainage will be directed to a purpose designed and built 450 kL sedimentation pond to remove sediments to design criteria. Refer to section 4.3, section 7.2 and section 7.6 of the EER for details. The Environment Division Landfill Sustainability Guide 2004 classifies landfill categories and specifies design criteria for the different categories. The Calder waste silica depot has been classified as a Category A landfill. The water management design criteria for a category A landfill is for a 1:10 year storm event for a 24 hours duration. The Calder design is for a much stricter 1:20 year rainfall event over a 10 minute duration. The 10 minute duration was selected based on the predicted time of concentration for the depot area. The 10 minute time of concentration gives a very high rainfall intensity of 90 mm/h for flow calculations. The rainfall rate for the 24 hours rainfall event is much lower at approximately 4 mm/h. The proposed sedimentation pond will achieve the following performance objectives:

The collection of 90% of the clay sized particles (<4 microns or µm)

The collection of 98% of the very fine silt (<8 µm)

The collection of 100% of all the coarser fractions (>16 µm). The settling performance for waste silica is predicted to be better than design due to the higher density of the silica compared to similar sized clay material. Sediment discharges similar to those that have historically caused beaching in the Inglis River in the vicinity of the proposed depot will not be possible from the proposed waste depot. Refer to section 7.6.4.of the EER. The default turbidity water quality objective for the Inglis River is expected to be <50 NTU, as derived from the Australian and New Zealand Guidelines for Fresh and Marine Water Quality 2000. Given the typical 10X dilution factor between the depot sedimentation pond outfall and the flow in the Inglis River, a turbidity limit of 50 – 100 NTU on the sedimentation pond outfall would seem reasonable. Two field measurements of the turbidity level of the sedimentation pond outfall will be taken during significant rainfall events in the first year of operations, to confirm performance objective. As a contingency measure TAM will install an extra sedimentation pond and/or a rip rap outfall drain diffuser if deemed necessary in future. The drainage line from the depot to the Inglis River is highlighted in red on the map in Appendix D.


6. Submission #3

6.1 Dust The waste silica does not present a dust problem when kept moist. Under these conditions the air emissions from the waste will be negligible. This is based on extensive TAM personnel experience with the material at several mines and at the Wynyard processing plant. If the dust emissions are controlled to OHS standards at the depot then it will comply with offsite ambient standards. Refer to section 4.4 and section 7.5 of the EER for details. Silica exposure is primarily an OHS issue rather than a public health issue. If dust did deposit on land it will become entrained into the soil matrix, due to its small particle size, along with the other clay sized particles. Silica does not represent a risk to drinking water supplies or groundwater supplies as it is completely insoluble in water and is not a chemical requiring monitoring in the Australian Drinking Water Guidelines 2004. Any silica in drinking water would be solely an aesthetic quality issue. Silica is essential for human life and is important in foods and is used in skin care products and collagen. It is also an essential element for animal and human health and is added to animal feed and occurs naturally in feed such as straw oats etc. Silica is not covered during disposal to the open cell as it is not required if the material is kept damp. The cell will be operated to ensure that the material is kept moist while it is open. The waste will be covered when the cell is full and waste has physically consolidated. The silica will be temporarily covered if deemed necessary during extreme weather. In general the placement and removal of a temporary cover has the potential to present a greater risk of causing air emissions than the management procedures proposed in section 4.4 and section 7.5 of the EER. Dust monitoring is proposed in section 7.5.4 of the EER. The aim is to undertake representative OHS monitoring at the operating cell to confirm achievement of OHS silica levels under the proposed management practices. Two OHS dust monitoring tests will be undertaken immediately downwind of the operating cell twice in the first year of operation. One test is proposed in spring (typically September/October) and one test is proposed in summer (typically January/February). The September/October and January/February tests times are deemed the most appropriate. The transport and spillage clean up requirements are outlined in the processing plant environmental management plan and in the processing plant permit conditions. The relevant environmental conditions in the Wynyard processing plant - Waratah-Wynyard DA 170/2005-A permit conditions are conditions A1, A2, A3, A4, G3 and Schedule 3. The conditions cover the materials storage and handling at the plant including the waste and the legal incident notification requirements. The same conditions will apply to the waste depot activity.

6.2 Land Contamination The waste silica is relatively pure and chemically benign and is purer than the land it will be situated on. The land in the area already contains siliceous materials so this material will not be foreign to the area.


7. Submission #4

7.1 Dust Refer to sections 4.1, 5.1 and 6.1 of this supplement.

7.2 Groundwater The potential impact on groundwater levels is negligible. The depot will be located on an elevated plateau from which approximately 5 m of gravel resource capping has been removed. The depot will be approximately 3.2 ha in area and located at an approximate elevation of 100 m. The area of the entire elevated plateau is approximately 20 ha. The depot will only be approximately 15% of the plateau area when considering the local plateau aquifer recharge and discharge. Under the gravel resource is a relatively impermeable rock. Building on this material will not alter the local infiltration rate of rainwater into the deep aquifer. The groundwater in the depot area is expected to follow the steep terrain to the west of the depot to an ephemeral tributary of the Inglis River located at an approximate elevation of 50m. The hydraulic gradient is approximately 0.25 (50 m drop over 200 m) which is high and will result in relatively high local draw down and low local groundwater levels. The hydro-geological assessment of the site is that the groundwater level under the depot floor area will be deeper the 2 m minimum design depth criteria for a Category A landfill. A visual inspection of the west bank of the proposed depot site showed no indication of groundwater surfacing from the bank for at least 20 m below the depot level, which supports the hydro-geological assessment. It is also assessed that the depot will not affect the groundwater level as the depot design will be free draining through the lateral drains and will therefore not place a high hydraulic head on the depot flooring. The quality of the water draining from the depot will be high as the silica presents no contamination risk. Some consultation has been undertaken with the Water Management Branch of the Department of Primary Industries, Parks, Water and Environment. Their initial comments are that given the location and distances involved, it is unlikely that the groundwater users in the area will be impacted by the proposed activity. Given the above assessment, no groundwater level and quality monitoring is deemed necessary and none is proposed.


8. Submission #5

8.1 Dust Refer to sections 4.1, 5.1, 6.1 and 7.1 of this supplement regarding dust from road transport. There is no potential for dust contamination of drinking water. Refer to sections 5.2 and 7.2 of this supplement.


9. Submission #6

9.1 Groundwater A search of the DPIPWE groundwater borehole register identified 3 registered groundwater boreholes in the region of the depot. They were all located on Calder Road and over 1 km to the east of the depot. A search of the DPIPWE water licences identified 3 surface water allocation licences in the region. One is 2.9 km to the north, one is 1.3 km to the south and one is 1.4 km to the east. Submission #6 raises the point that spring water is used by a local residence. Assuming that the spring is located at the nearest residence, the nearest spring water user would be at least 600 m from the depot and on the eastern side of the depot location. Given the following points:

Distance to relevant receptor sites

The interspersed surface water drainage lines to the west

The predicted groundwater flow direction to the west. The risk of potential impact on local groundwater quality and spring water quality is very low and will not increase the risk to human health above that which already exists from other sources and contaminants. Refer to section 7.2 of this supplement for other comments as well as section 4.5 of the EER.

9.2 Dust The carrying out of monthly OHS monitoring is not deemed necessarily. Monitoring immediately adjacent to the operating cell on two occasions during the first year is deemed appropriate and representative. Compliance with OHS standards will achieve ambient standards. Refer to sections 4.1, 5.1, 6.1 of this supplement and section 7.5 of the EER. OHS air monitoring is a specialist field and is carried out by an independent consultant to Australian Standards. The monitoring results will be reported to the appropriate authority. No ambient air monitoring is proposed unless the OHS monitoring indicates otherwise.

9.3 Noise Refer to section 4.2 of this supplement.

9.4 Flora The premises boundary (6.7 ha) overlaps some regrowth vegetation on the soil stockpiles from the original land clearing for mining. The depot (3.2 ha) will be located on cleared land in the centre of the premises boundary. The small amount of stockpiled soil around the proposed depot was previously stored for rehabilitation purpose. Some clearing of this peripheral regrowth may occur in certain areas for soil recovery for rehabilitation purposes.


10. Submission #7

10.1 Material Properties The thixotropic properties of the material are well understood by TAM personnel and these properties are dealt with on a daily basis at the mines and at the processing plant. The TAM personnel are able to drive on the material once drained and consolidated. Flocculants are used in many industries including the water treatment industry and mining industries. The flocculant is not persistent in the environment, biodegrades and any remnant flocculant in the depot material has the potential to assist settling in the sedimentation pond. Analysis of the flocculant in the waste silica is deemed unnecessary. No analysis is deemed necessary for the current disposal at Heybridge. Excess water will drain from the waste silica but the waste has the ability to retain a moisture content that prevents dusting. At the same time the lower remnant water content is low enough for physical stability to be achieved as the waste consolidates. This property to retain remnant water is useful in potting mixes and uses as a rehabilitation medium. There is ongoing interest in using this waste as a soil conditioner. Trials are planned for its use on Tasmanian pastures.

10.2 Landfill Design The depot wall is designed to be free draining and designed to the contemporary standards and design tables from the Design of Small Dams (US Bureau of Reclamation). The wall will be stable during a seismic event as no deformation or liquefaction can occur in a free draining wall with a low phreatic zone. No seismic risk analysis is necessary for the wall design. The nominal disposal rate is currently approximately 20,000 m3/year, but the maximum requested permitted rate is 49,500 m3/year. This maximum disposal rate will allow for any future contingencies. The material will be uncovered but managed to prevent dusting. The material will be allowed to drain and consolidate and become ‘stabilised’. When drained and consolidated the risk of liquefaction is greatly reduced. The design is finalised. The final design reference in the EER is basically the sign off by a civil/geotechnical engineer on a stability analysis before construction begins using the proprietary slip circle software to establish/confirm an acceptable safety factor, following a check of the material to be used for the construction sourced from the site and from Hanson quarry. As mentioned above, the design is sound and basically finalised and there is no potential for other discharges. The 1:20 year 10 minute duration design rainfall event and resultant flow calculations are also very conservative and sound. This design rainfall event results in a flow rate 20 times higher than that specified in the Environment Division’s Landfill Sustainability Guide 2004. The drain design has been undertaken. The design will be signed off following the civil/geotechnical check of the material to be used in construction as mentioned for the depot wall construction.


The depot underdrainage may become partly fill (as occurs in most underdrainage systems) until maintained at a certain level by the base flows. This does not mean that the silica will flow through the wall in any great quantities. The sedimentation pond will collect a design loss of approximately 20 m3/year of sediment. The sediment pond design will minimise loss of sediment to the receiving environment. Refer to section 4.3 of the EER and section 5.2 of this supplement. The depot will be located on an excised area of the Hanson mining lease and there is an abundance of construction material available on the surrounding Hanson lease. The depot wall has been engineered and a clay core is not required or included. A basic design of the cell capping cover has been included in the EER. The cover performance and revegetation success will be reviewed during operations. The final cover will conform to the Environment Division’s Landfill Sustainability Guide 2004.

10.3 Water Quality There are commitments to water turbidity monitoring and dust monitoring. These commitments will be incorporated into the table of commitments. Refer to original sections 7.6.4 of the EER and now sections 5.2 and 15 of this supplement. The depot operation will present a low risk to the quality of the receiving waters above the impact which already exists. No crayfish survey is deemed necessary. The depot is more than 50 m from a water course as required by the Environment Division’s Landfill Sustainability Guide 2004.

10.4 Groundwater No groundwater survey is deemed necessary. Refer to sections 7.2 and 9.1 in this supplement. Sodium and pH monitoring is not deemed necessary for the Calder depot as the waste silica does not contain caustic soda. The waste silica is a highly stable, chemically inert and environmentally benign material. Monitoring at the Heybridge facility is probably related to the historical co-disposal of caustic paper industry waste sludge and other wastes. The quality of raw silica resource and the waste silica does not change in relation to its potential impact on the environment. The concentrations of impurities such as iron/rust which determine whether the raw silica is product or whether it is waste silica is in the order of parts per million. The pH of the water content of the waste silica is ≈6.7 which is a natural near neutral 7.0 pH (rain pH ≈5.5). The groundwater will be protected by the underdrainage in the depot. Regardless, the quality of the water entrained in the waste silica presents no risk to groundwater quality.

10.5 Flora and Fauna The premises boundary is shown in Appendix E of the EER. The depot boundary is inside this premises boundary. The depot footprint (3.2 ha) is primarily on cleared land in the centre of the 6.7 ha premises boundary. There is some soil stockpiled around the depot site that was stored following mining and this has historically been earmarked from rehabilitation purpose. Some clearing of the regrowth on the soil stockpiles may occur for soil recovery for rehabilitation purpose but this will be minimal.


No flora or fauna surveys are deemed necessary. The proposed depot site is cleared and approved mining activity occurs around the site. The surrounding mining activity is a level 2 activity regulated by the EPA and MRT. The potential impacts from the proposed depot activity will be less than the current mining activity and regulated by the same authorities.

10.6 Noise The proposed waste silica depot will be assessed and regulated as an operation under the Environment Division’s Landfill Sustainability Guide 2004 and not the Quarry Code of Practice. The recommended operating hours in the Landfill Sustainability Guide 2004 are 0700 to 1800 Monday to Saturday and 0900 to 1800 Sunday. This proposal is requesting operating hours of 0700 to 1900 hours Monday to Friday and 0800 to 1600 on weekends. Although the proposed weekday hours are 1 hour later, the weekend hours are lower by 3 hours on Saturday and 1 hour on Sunday. The total weekly hours will be I hour more per week than the Guide. The difference is not deemed significant. It is possible that that the Calder Road residences may prefer the lower weekend hours.

10.7 Dust The proposal seriously considers dust emissions. TAM has extensive experience and management knowledge with dust emissions at all its premises. A dust management regime has been presented in the EER. The regime includes the measures to minimise dust emissions and implementation of the measures will reside with the operator. TAM will be responsible to ensure that the operator implements the dust minimisation measures in accordance with existing and potentially future permit conditions and the Environmental Management and Pollution Control Act 1994 (EMPCA). Dust will be monitored. Refer sections 4.1, 5.1, 6.1, 7.1, 8.1 & 9.2 of the supplement. There is a very good, permanent water supply adjacent to the depot site.

10.8 Transport Transport spillage will be regulated by the existing conditions in the processing plant permit and the legal incident notification provisions of the EMPCA. Similar permit conditions and legal requirements will apply to the new depot permit. No dedicated cleanup plan currently exists for Heybridge and one for Calder is deemed unnecessary. Any transport spillage will be barricaded and cleanup immediately discovered. TAM can source appropriate vacuum truck contractors in the event of a spillage and dispose of the cleanup to the depot.

10.9 Risk Assessment/Contingency Plans Risk assessments and contingency plans beyond those already discussed in the EER or in this supplement are deemed unnecessary. The risks are already deemed to be very low, so no need exists for any further assessments.


The reasons are outlined as follows:

The truck route, distance and speed limits do not warrant the risk assessment of truck rollovers (refer section 7.9 of the EER)

The risk of fire emanating from the depot is negligible as the site is basically cleared. For fires approaching from outside the depot, the depot site acts as a safe emergency meeting point and a strategic fire fighting site

The risk of dust storms emanating from the depot operations have been cover in the dust sections of this supplement

The risk of trucks sinking into the waste silica has been covered in this supplement. Trucks will not be travelling on uncovered, unconsolidated waste

The risk of earthquake damage has been discussed in the wall design in section 10.2 of this supplement. The wall design minimizes the risk of the depot wall failure in a seismic event

The risk of water contamination has been discussed in sections 5.2, 7.2, 9.1, 10.2 and 10.3 in this supplement

The risk of a depot wall breach is covered under the earthquake comment above

The risk of silica loss has been covered under sections 5.2, 7.2, 9.1 and 10.2 in this supplement.

10.10 Rehabilitation/Revegetation The preliminary rehabilitation strategy and plan has been outlined in the EER as per the Landfill Sustainability Guide 2004. The EER has been developed in consultation with Forestry Tasmania. The final closure rehabilitation plan will be developed over time in accordance with the Landfill Sustainability Guide 2004 to the satisfaction of the Director and the Environment Division. In the interim, the closed cell will be covered with approximately 300 mm of compacted clean fill as per the guide and the depth of the final cover (potentially an extra 0.5 m deep, for a total of 0.8 m) will be assessed based on the performance of the compacted layer. It is possible that given the benefits of the waste silica as a growth medium that a depth between 0.3 m and the total final depth of 0.8 m in the guide will be adopted over time. The depot will be rehabilitated in accordance with the guide, or as amended at any time by the Director.


10.11 Heritage No Aboriginal heritage or European heritage surveying was deemed necessary for the EER. This was based on the fact that site has been historically extensively mined by several operators over many years even up to very recently in adjacent areas. A history of the depot site area is included below. The history is courtesy of john miedecke and partners – Hanson Construction Materials Calder ML68M 1980 – Rehabilitation Plan – July 2005.

The area has a long history of gravel extraction and there are numerous gravel pits located in the vicinity. It is understood that Brambles were an early lease holder and sands and gravels were quarried and processed mainly in the ‘Ponderosa’ area for the construction of the Hydro Electric Commission’s dams and power stations which were constructed in the 1970s on the Mersey and Forth Rivers. Besser purchased the lease from Brambles and operated a wet and dry screening plant at the Ponderosa site for many years before the resource was worked out and the screening plant transferred to its current site.


11. Submission #8

11.1 Dust The aim is to undertake the OHS monitoring during spring and summer weather in the first year of operations. Depending on the results, subsequent monitoring will then be undertaken as required by the Director of Workplace Standards Tasmania. The dust covers and tray modifications fitted to the current waste transporter trucks, which transports the waste to Heybridge, appear to be working well. The same equipment will be used for the Calder depot. Refer to previous dust sections in this supplement regarding the potential impact of dust in the area. TAM personnel advise that the waste silica will not dry out overnight. It can take several days of dry hot weather before the material starts to exhibit any dusting. If the exposed waste is damp when the depot is closed each evening, then the waste will not commence dusting overnight. The placement of fresh waste each day in the cell on top of the old waste will ensure that a damp cover exists all the time. Should the processing plant shut down the operator will water the waste or apply a temporary cover as outlined in the EER.

11.2 Noise The depot operating hours are based on the production rates at the processing plant, the capacity of the waste storage at the processing plant and the preventative maintenance schedules. The proposed 7 days a week depot transport regime is preferred to reduce the risk associated with stockpiling waste over the weekends and to maintain existing approved waste management practices at the processing plant.


12. Planning

12.1 Traffic Refer to section 4.2 of this supplement.

12.2 Land use The area is Crown land managed by Forestry Tasmania. Hanson have excised the waste depot premises boundary from ML 68M 1980. TAM has taken up a lease over the designated waste depot premises boundary with MRT. TAM will be the responsible person for the operation. No gravel extraction activity can be undertaken by Hanson on the waste depot site. Waste silica disposal can only occur on the waste depot site. It is not possible for silica flour to chemically contaminate the gravel product. If waste silica was inadvertently spilled onto the surrounding gravel resource, it would be washed out along with the existing gravel fines when processed at the Hanson washing plant. Alternatively, if gravel ends up in waste silica it will be disposed of to the waste depot.

12.3 Security The site will have appropriate warning signs and barriers. Security fences are not proposed. It is deemed unwise at this time to hinder the access by other parties to surrounding remnant gravel resources, surrounding rehabilitation commitments and surrounding fire fighting tracks. Should security become an issue in future, a possible contingency is to install a moveable stock-proof picket and wire strand fence around the operating cell in accordance with the Category A landfill guide recommendation.

12.4 Fire Fighting Refer to section 10.9 of the supplement.


13. General

13.1 Traffic The normal trucking rate will be 3 to 4 truck loads per day (current rate to Heybridge) on Calder Road which currently takes on average 1,670 vehicle movements per day. A maximum of 10 truck loads per day is proposed in the event that there is a temporary spike in production rate and to cover any potential unavailability of the waste transport contractor due to mechanical failure or industrial disputes etc.

13.2 Responsibility TAM will be the lawfully ‘responsible person’ and the owner/operator/manager of the depot and responsible for the waste material handling, transport, disposal and operation of the waste depot on the designated waste depot site. Refer to sections 3.1 and 4.4.3 of the EER.

13.3 OHS The depot operator will not be driving on the waste silica until the waste has consolidated and the cell has been closed and capped. The waste silica will be spread and compacted in the operating cell using a long armed excavator.

13.4 Document Assume maps in the EER are orientated with the top of the map being north.

13.5 Reporting The depot environmental reporting will be incorporated into the existing TAM processing plant environmental management reporting requirements.


14. EPA Divisional Request A map clearly identifying the location of the closest residences to the depot site and the access road intersection with Calder Road is contained in Appendix B.


15. Management Commitments

No. Commitments When Responsible

Person EER section

Air Emissions

1 The waste silica in the active open cell will be levelled and tamped down daily and watered

when necessary

During depot life

Depot operator

7.5

2

Dust emissions will be minimised during severe weather conditions by watering roads, depot surfaces and the waste silica. In extreme conditions a gravel cover or a similarly effective cover may be place over the waste silica

During depot life

Depot operator

7.5

3 Traffic speeds on the depot and access roads will be limited to <25 km/h

During depot life

Depot operator

7.5

Liquid Waste

4 Waste disposal activities will not be undertaken during torrential rainfall events

During depot life

Depot operator

7.6

5

The depot surface water and depot drainage water will be contained and directed to a sedimentation pond before final runoff to the

existing naturally vegetated drainage lines

During depot life

Depot operator

7.6

6

The volume of fuel stored in any site mobile tanker will be restricted to approximately 1,000 L. The tanker will carry fuel cleanup

equipment in case spills occur on site

During depot life

Depot operator

7.6

7

The Director, Environment Protection Authority, will be notified as soon as possible but no later than 24 hours of any hydrocarbon spill

During depot life

Depot operator

7.6

8

Any hydrocarbon contaminated soil will be removed immediately and taken to an appropriate authorised disposal facility by an authorised transport contractor

During

depot life

Depot

operator 7.6

Noise Emissions

9

The waste depot and waste transport operating hours will be restricted to between 0700 hours and 1900 hours on weekdays, 0800 to 1600 hours on Saturdays, Sundays and

gazetted public holidays

During depot life

Depot operator

7.8

Supplement additions When Responsible

Person Supplement

Section

10

Two field measurements of the turbidity level of the sedimentation pond outfall will be taken during significant rainfall events in the first year of operation, to confirm

performance objective

During depot life

Depot management

5.2

11

Two OHS dust monitoring tests will be undertaken immediately downwind of the operating cell twice in the first year of

operation

During depot life

Depot management

6.1

12

The depot environmental reporting will be incorporated into the existing TAM processing plant environmental management reporting

requirements

During depot life

Depot management

13.5


Appendix A

EPA Summary of Representations

pitt&sherry ref: HB11206H001 App A 31P Rev 00/JL/mn

Tasmanian Advanced Minerals Silica Flour Disposal, Calder Summary of Public and Agency Comments

A. - Relevant Public Submissions

Submission No. Issue Comment

Environmental

1 Dust Dust from vehicle movements on route to the site including site access.

Separation distance between traffic and residences and the site and residences.

Noise Noise from additional vehicle movement and effects on livestock (horses and cattle) and residences.

2 Dust Health impacts.

Water quality Effect of sediment discharge on the Inglis River. Notes sediment discharge has occurred in the past in the vicinity of the site resulting in sediment beaches in

the Inglis.

3 Dust Health Impacts from dust, dust deposition on land and in drinking water supplies.

Has the following questions:

Why is silica flour not to be covered?

Why no dust monitoring program?

Why no transport spillage monitoring and cleanup plan?

Land contamination From sediment discharge to land.

4 Dust Health impacts.

Groundwater Potential impact on the ‘water table’ [groundwater] and discharge of groundwater to the Inglis River. Query why there is no groundwater monitoring?

5 Dust From road transport.

Potential contamination of drinking water.

6 Groundwater Potential contamination of a spring from which potable water is extracted.

Dust Considers air monitoring should be monthly and carried out by an independent authority and made publically available.

Noise From truck movement along transport route and activities on the land.

Flora Asserts vegetation will be removed.

7 Material properties Contends that there is no understanding of the ‘thixatropic’ nature of silica flour and the potential for release of the material. Contends the material is not suitable for construction of a ‘stable landform’.

Queries how large vehicles (‘40tonne truck’) could be driven on top of the material after deposition and covering to a depth of no more than 300mm. Does not believe it is possible.

Analysis of silica waste does not appear to include the flocculant used for settling.

Implies the concept of the material being ‘free draining’ and of the material retaining water thus preventing dust generation are incompatible.

Landfill design Queries the design philosophy ie a ‘free flowing’ system. States that material is not ‘free draining’ contending that drainage will mobilise the material. Infers design should be to contain the material and prevent drainage.

Notes a discrepancy between the concept design disposal rate (20,000m3 per year) and the proposed disposal rate (49, 500m3 per year).

No analysis of seismic risk.

Concerned the material will be uncovered and therefore will in effect be ‘unstabilised’ and leave ‘3m of quicksand’ exposed.


Considers final drainage design required to enable assessment. Queries the 1 in 20 year standard for drainage design and the quality of calculations without a final landfill design. Concerned that the potential exists for other discharge locations until such time as a final design is produced.

Believes the statement that the drains (“which are not yet designed”) will be partially filled with silica is an acknowledgement that silica flour will move through the wall and discharge to the environment.

Questions the availability of materials for wall construction given that site has been “worked out’.

Without a final design, queries how the landfill retaining wall will support large vehicles and how it can be determined that the wall will not breach under operational conditions, thereby releasing silica. Considers engineered and lined clay cored walls are necessary.

Considers that the capping layer must be fully design before the project can be considered due to the potential for water and vegetation growth damaging the liner and exposing silica.

Water quality No commitment to turbidity monitoring or dust monitoring program.

Concerned that a creek is very close to the western boundary of the site and yet there is no survey for giant freshwater crayfish.

Groundwater No groundwater survey thus the impact on groundwater levels as a result of disposal of damp material cannot be assessed.

Queries why no pH and sodium monitoring given these requirement at the current disposal facility.

Contends these parameters may change with changing quality of silica processed. Refers to previous changes in resource characteristics of silica product form Corinna as evidence that contaminant loads may change and thus monitoring programs should reflect this.

No groundwater protection without a clay liner.

Flora and Fauna Appendix E shows vegetation on the site upon which the proposal is to be situated thus it is contended that the statement that no vegetation will be cleared in the report is erroneous.

Queries why there is no flora and fauna assessment. Eagles and orchids are listed as examples of threatened species for consideration.

Noise Operating hours are extended beyond those recommended by the Quarry Code of Practice.

Dust Concerned about statements such as “in the rare event dusting is an issue..” and cover will only be applied “if necessary” and in “severe weather”. Considers dust generation to be a significant issue. Considers that without precise definitions of condition where cover is required regulation will not be possible.

No commitment to a dust monitoring program.

No emergency water source for dust suppression during drier months.

Transport Queries why there is no spillage monitoring and clean-up plan for the transportation route.

Risk assessment/

Contingency plans

Considers a risk assessment should have been conducted. Examples of aspect where contingency plans are considered merited are provided as:

Truck rollover

Fires

Dust storms

Trucks sinking into silica

Earthquake

Water contamination

Dam breach

Silica flow into creek

Rehabilitation/

revegetation

Queries why no rehabilitation and revegetation plan has been provided. Notes that it is stated in the EER that rehabilitation of the site is a major objective of the proposal.

Considers there to be insufficient detail regarding the potential for erosion, weed management, disease control and ongoing maintenance and monitoring.

No discussion of quantity, depth, source and sterilisation of covering materials and mulch.

Heritage Considers that a heritage assessment of the site should have been carried out (whether an aboriginal or European heritage assessment is not stated)

8 Dust Once a year inadequate given variable and extreme weather conditions.

Dust covers are not successful on current vehicles [carting gravel] moving to and from the site.

No consideration of the impact of dust on livestock.

How are dust mitigation measures to be implemented and the site to be monitored out of hours during extreme conditions?

Noise Operations 7 days a week unacceptable. Requests operations be limited to 5 days a week.


Planning

1,2,4,8 Traffic Increased traffic on route and impact on amenities. How many vehicle movements per day? Traffic impact needs to consider all road uses (not just number of heavy vehicles) and the need potentially to reduce speed limits.

7 Land use What arrangements are being made in relation to the title? How are they to ensure no gravel extraction impacts upon the disposal facility? How are they to ensure silica flour does not contaminated gravel product?

Security Considers a boom gate insufficient. Security fences required to stop, for example, BMX/trail bike riders sinking into disposal areas.

Fire fighting Has fire risk been assessed and what systems will be put in place?

General

2 Traffic Amount of traffic on the road.

7,8 responsibility Legal liability for dumped material not clearly stated in the EER.

8 OH&S Lack of safety procedures are there for operators driving on 3m deep deposited silica waste.

document Maps/aerial photos do not have north arrow as is generally required.

reporting Concerned no ‘requirements’ for annual reporting.

B. - EPA Division Request The EPA Division requests a map(s) clearly identifying the location of the closest residences to the proposal site and to the access road from the junction of the access road with Calder Road. Distances of the residences must be provided. Maps and plans must include a north arrow and a scale.


Appendix B

Closest Residences to the Depot and Calder Intersection

pitt&sherry ref: HB11206H001 App B 31P Rev 00/JL/mn


Appendix C

Residential Properties on the Transport Routes

pitt&sherry ref: HB11206H001 App C 31P Rev 00/JL/mn

The information for land parcels within a 50m buffer of the road centreline is shown below (information courtesy of the LIST). Route 1: Stennings Road to Minna Road contains 674 private land parcels (shown in red) Route 2: Junction of Calder Road to Proposed Silica Southern Access Road contains 102 private land parcels (shown in blue).

Scale 5 km

N


Appendix D

Predicted Surface and Groundwater Drainage Path

pitt&sherry ref: HB11206H001 App D 31P Rev 00/JL/mn

Predicted surface water and ground water drainage path from the depot to the Inglis River – highlighted in red

Predicted drainage path

to Inglis River

Scale 1 km N

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