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Hydro Tasmania Lake Rowallan Borrow Areas – Environment Effects Report

Prepared By: Barry Williams

Date: 20 September 2013

Issue Date Recipient Organisation

Draft Brian Daws Hydro Tasmania

Draft 2 29 August 2013 Brian Daws Hydro Tasmania

Draft 3 4 September 2013 Clare Lond-Caulk Environment Protection Authority

Draft 4 16 September 2013 Leanne Rabjohns Meander Valley Council

Final 20 September 2013 Leanne Rabjohns Meander Valley Council

Lake Rowallan Borrow Areas – Environment Effects Report Final

Integrated Land Management and Planning | Table of Contents 2

TABLE OF CONTENTS Table of Contents .................................................................................................................................... 2

Figures ..................................................................................................................................................... 4

Tables ...................................................................................................................................................... 4

Part A - Proponent Details ...................................................................................................................... 5

Part B – Project Description .................................................................................................................... 6

1 Description of Project ..................................................................................................................... 6

1.1 Main Activities......................................................................................................................... 6

1.1.1 Rock Quarry 2 .................................................................................................................. 6

1.1.2 Clay Borrow A .................................................................................................................. 8

1.2 Timing of the Works ................................................................................................................ 8

2 Project Area .................................................................................................................................. 10

2.1 Vegetation ............................................................................................................................. 10

2.2 Land use ................................................................................................................................ 10

2.3 Land tenure ........................................................................................................................... 15

2.4 Geology ................................................................................................................................. 16

2.5 Geomorphology .................................................................................................................... 16

2.6 Description of the resource .................................................................................................. 18

3 Map and Site Plan ......................................................................................................................... 18

3.1 Mining Plans .......................................................................................................................... 21

3.1.1 Clay borrow A ................................................................................................................ 21

3.1.2 Rock Quarry 2 ................................................................................................................ 21

4 Rationale and Alternatives ............................................................................................................ 22

Part C Potential environmental effects ................................................................................................. 23

1 Flora and fauna ............................................................................................................................. 23

2 Rivers creeks wetlands and estuaries ........................................................................................... 24

3 Significant areas ............................................................................................................................ 25

4 Marine areas ................................................................................................................................. 25

5 Air emissions ................................................................................................................................. 25

6 Liquid effluent ............................................................................................................................... 26

7 Solid waste .................................................................................................................................... 26

8 Noise emissions ............................................................................................................................. 26

9 Transport impacts ......................................................................................................................... 27


Integrated Land Management and Planning | Table of Contents 3

9.1 Preparation ........................................................................................................................... 27

9.2 Embankment reconstruction ................................................................................................ 27

9.3 Traffic Management.............................................................................................................. 27

10 Other off-site impacts ............................................................................................................... 28

11 Hazardous substances and chemicals ....................................................................................... 28

12 Site contamination .................................................................................................................... 28

13 Sustainability and climate change ............................................................................................ 28

14 Cultural heritage ....................................................................................................................... 28

15 Sites of high public interest ....................................................................................................... 29

16 Visual impact ............................................................................................................................. 29

16.1 Road users ............................................................................................................................. 29

16.1.1 Rock Quarry 2 ................................................................................................................ 29

16.1.2 Clay Borrow A ................................................................................................................ 29

16.2 Walking tracks and other vantage points ............................................................................. 29

16.2.1 Walls of Jerusalem Walking track ................................................................................. 29

16.2.2 Logging coupe on Clumner Bluff ................................................................................... 30

17 Rehabilitation ............................................................................................................................ 32

17.1 Clay borrow area A ................................................................................................................ 32

17.2 Rock quarry 2 ........................................................................................................................ 33

Part D – Management commitments ................................................................................................... 34

Part E – Public consultation .................................................................................................................. 36

References ............................................................................................................................................ 36

Appendices ............................................................................................................................................ 37

Appendix 1 Mining Plans ...........................................................................................................................

Appendix 2: Botanical Survey and Fauna Habitat Assessment .................................................................

Appendix 3 Weed and Plant Pathogen Management Plan .......................................................................

Appendix 4: Rainfall Runoff Calculations ..................................................................................................

Appendix 5: Archaeological Report Review Form ....................................................................................


Integrated Land Management and Planning | Figures 4

FIGURES Figure 1: Locality Plan - Extract from 1:100,000 Series Topographic Mersey 8114 ............................. 16

Figure 2: region Plan - cadastre ............................................................................................................ 19

Figure 3: Local Plan - Borrow Areas ...................................................................................................... 20

Figure 4: Borrow A – Mining Plan ............................................................................... Appendix 1 page 1

Figure 5: Rock Quarry 2 – Mining Plan ........................................................................ Appendix 1 page 2

Figure 6: Borrow A – Rehabilitation Plan .................................................................... Appendix 1 page 3

Figure 7: Rock Quarry 2 – Rehabilitation Plan ............................................................ Appendix 1 page 4

TABLES Table 1: Proponent details ...................................................................................................................... 5

Table 2: Operation details ....................................................................................................................... 9

Table 3: Project Area details ................................................................................................................. 15

Table 4: Climate Data ............................................................................................................................ 17

Table 5: Planting schedule clay borrow A rehabilitation ...................................................................... 32

Table 6: Planting schedule rock quarry2 face rehabilitation ................................................................ 33

PLATES Plate 1: Rock Quarry 2 showing northern face ....................................................................................... 7

Plate 2: Looking over Clay Borrow A ....................................................................................................... 8

Plate 3: Looking northwest from Walls of Jerusalem Track .................................................................. 30

Plate 4: Looking west from logging coupe below Clumner Bluff .......................................................... 30


Integrated Land Management and Planning | Part A - Proponent Details 5

PART A - PROPONENT DETAILS TABLE 1: PROPONENT DETAILS

Proponent Hydro Electric Corporation trading as Hydro Tasmania

ACN 072 377 158

Address 4 Elizabeth Street

Hobart TAS 7000

Postal Address GPO Box 355

Hobart TAS 7001

Contact Mr Brian Daws

Phone (03) 6230 5253

Mobile 0417 080 205


Integrated Land Management and Planning | Part B – Project Description 6

PART B – PROJECT DESCRIPTION

1 DESCRIPTION OF PROJECT The Proponent is undertaking strengthening works on the Lake Rowallan Dam. The Lake Rowallan Dam is a clay core earth fill dam commissioned in 1968. Work on the concrete spillway is complete and work on the earth fill embankment is planned to commence in the 2014-2015 construction season.

To facilitate the embankment works it will be necessary to lower the full supply level (FSL) of the impoundment (Lake Rowallan) to below the lowest point of the works. This work can only proceed when there is a low level of risk that an intense rainfall event will interrupt activities. Statistical records for the weather station at Mole Creek (91065) show the months with the lowest accumulated rainfall total are November through to March. (BOM, 2013). The construction season is November through to April, allowing for the refill of the lake.

The works consist of removing sections of the supporting rock fill and the central clay core. A new contact layer must then be applied to the rock foundation to the embankment. The clay core and supporting rock fill will then be replaced in layers until the crest height is reached. As the clay and rock materials are removed it is inevitable that some mixing will occur. Extra clay and rock materials will be required to replace excavated materials that are impure. Materials required include extra clay core and rock fill materials. It is estimated that approximately 8 000 cubic metres of clay and 10 000 cubic metres of rock will be required.

The original dam construction works utilised sites close to the dam site to win the products required. These sites have been evaluated and will again be used as borrow areas to provide the construction materials. Investigation works on the clay borrow areas and rock quarries indicate that the desired quantity and quality of product is available from the sites represented as Clay borrow A and Quarry 2 in Figure 1.

1.1 MAIN ACTIVITIES The proposed extractive works will occur in two locations; the rock quarry 2 and clay borrow A. Cartage activities will be carried out between these sites and each side of the dam embankment. It is not possible to cart across the dam embankment because of the central spillway.

Activities associated with the placement and compaction of the materials is included in the Dam Permit issued under a separate and independent approval process.

1.1.1 ROCK QUARRY 2 The original investigation into suitable materials for the reconstruction works included the two original rock quarries. Rock quarry 2 was found to have superior material characteristics and will be the sole source of rock construction materials for this project. Quarry 1 will be utilised as a hardstand and stockpiling area.


Integrated Land Management and Planning | Description of Project 7

Previous extractive operations at rock quarry 2 exploited a rock outcrop that resulted in a legacy face around 12 metres in height. The southern end of this face is partly covered with self-sown natural revegetation. The northern face is more active and presents as disturbed ground as seen in plate 1.

PLATE 1: ROCK QUARRY 2 SHOWING NORTHERN FACE

The new extractive operation will utilise an original track to access the highest part of the existing quarry face. A pattern of drill holes will be installed down to a level approximately 5 metres above the existing quarry floor. The subsequent shot will continue the existing face to the north, while maintaining a clear distance to the higher rocky outcrop approximately 20 metres behind and above in the landscape.

The first series of shots will create a bench 5 metres above the quarry floor. The second series of shots will extract the rock from this bench down to quarry floor level, whilst leaving a 4 metre wide bench in the new face. The border of the quarry floor along the edge of West Rowallan Track will be extended around the corner to improve sight distance. Continuing north from this a 10 to 15 metre wide vegetated screen will remain to help conceal the workings and reduce wind speed locally to control dust.

Hydro Tasmania geologists believe the rock from Quarry 2 will fracture into ideal sized elements and there should be minimal waste. Any undersized can be utilised for gravel road maintenance works during the course of the project.

Equipment used in this operation will include a small excavator to clear the vegetation from the access track and proposed footprint; a mobile drill rig to install the holes to accommodate the explosives; a dozer to rip stubborn shot rock and for pushing product onto the bottom bench and a



larger excavator with a breaker attachment to load the trucks and break down oversized particles. The actual equipment utilised will be determined by the earthworks contractor.

1.1.2 CLAY BORROW A Clay borrow A is situated on the shoreline to the impoundment. The area is substantially un-vegetated, with only sparse isolated low shrubs and marsupial lawn where informal camping occurs. It is intended to extract the clay by direct excavation. Previously developed test pits indicate that the clay / silt layer is around 4 metres thick. The clay / silt is interspersed with pebbles, cobbles and boulders as indicated by the surface expression of the formation in plate 2. The concentration of the larger particles reduces with depth but is variable across the deposit.

PLATE 2: LOOKING OVER CLAY BORROW A

It will be necessary to process the entire clay product through a grizzly and mechanical vibrating screen. The minus 40 mm component will be suitable for placement and the balance will be stockpiled on site to be used in re-constructing the foreshore area. The actual volume of raw product extracted to produce 8 000 cubic metres of usable clay is unknown but may be as much as 24 000 cubic metres.

Equipment used in this operation will include an excavator to strip unsuitable material and vegetation from the surface of the deposit; a large excavator to win the product and produce stockpiles; a small mechanical screen and a wheel loader to feed the screen and load the trucks. The actual equipment utilised will be determined by the earthworks contractor.

1.2 TIMING OF THE WORKS The actual excavation and replacement of the structural components within the dam embankment will occur in a window over the summer months of 2014/15 to take advantage of the natural draw down of the lake, the long daylight hours and a reduced risk of a rainfall event intervening. These



works will be time critical and the lower sections of the dam will be excavated and placed in potentially a ‘round the clock’ operation that will not stop until the embankment has been reconstructed to a level that can withhold a substantial storm event.

The preparatory works in the quarry and clay borrow A will occur prior to the construction work. It is planned for the works in the clay borrow and quarry to commence in January 2014. These activities will continue until the required quantities of materials have been won and stockpiled. The hours of operation will be normal daylight hours but with high likelihood of extended working weeks as a result of the remote location.

The cartage and placement operation will occur in the 2014 / 2015 construction season, with the most intensive period possible in January / March. As discussed previously the hours of operation for these activities will be up to 24 hours as circumstances dictate.

TABLE 2: OPERATION DETAILS

Maximum Production (Clay core) 24 000 cubic metres production in 2013 / 2014

Maximum Production (Rock fill) 10 000 cubic metres production in 2013 / 2014

Preparatory works Weekdays Weekend

Daylight hours Daylight hours

Embankment works Up to 24 hours Up to 24 hours

Expected closure Clay borrow 2016 Rock quarry 2016

Blasting (rock quarry) 3 blasts per week in rock quarry when fully operational.


Integrated Land Management and Planning | Project Area 10

2 PROJECT AREA Lake Rowallan is located on the upper reaches of the Mersey River at the base of an escarpment of the Central Highlands. The lake is one of a series of hydroelectric power generating facilities on the Mersey and Forth Rivers. The escarpment marks the boundary to the Tasmanian Wilderness World Heritage Area and the Walls of Jerusalem National Park.

2.1 VEGETATION The lake is artificial, being created for power generation. There has been not attempt to recover the timber from the inundated area and views of the lake are characterised by the standing dead trees emerging from the lake surface. The lake is directly surrounded by state forest that has been the subject of recent forestry activities. These forests are a mosaic of Eucalyptus dalrympleana forest, E. delegatensis forest over rainforest, E. amygdalina costal forest and woodland, E. amygdalina forest and woodland on dolerite and E. dalrympleana – E. Pauciflora forest and woodland (Hydro Tasmania Consulting, Nov 2009). More details on floristic structure are included in the Botanical Survey and Fauna Habitat Assessment (North Barker Ecosystem Services, Dec 2012). The only permanent structures located close to the lake is the dam embankment and the hydroelectric power station that is situated underground.

2.2 LAND USE The Mersey River White Water Reserve is situated on the downstream side of the dam and has an amenities block used for canoeing and kayaking recreational events. The Mersey Forest Road continues along the east side of the lake to the terminus of the Walls of Jerusalem Walking Track.

The land surrounding the Lake Rowallan and the borrow areas is State Forest managed by Forestry Tasmania. The most immediate land use is forestry operations and hydroelectric power generation. Lake Rowallan is an important trout fishery managed by the Inland Fisheries Service. Lake Parangana is also a lesser trout fishing water and the Mersey River between the two is utilised for white water canoeing activities. The Arms River Forest Education Reserve is located a short distance along Maggs Road.

There are no local residents or facilities that might be considered sensitive uses. The nearest actual residence is situated on Walters Road at Liena over 16 kilometres to the north of the closest operations area.

Land Use Planning is regulated by the Meander Valley Council through the Meander Valley Planning Scheme 1995 (updated April 2012). The following section addresses the relevant sections of the Scheme:



2.2.1 MEANDER VALLEY PLANNING SCHEME 1995 - RESPONSE PART ONE – ABOUT THIS SCHEME 1.8 Planning Scheme Strategy 1.8.3 Rural Strategy The rural strategy is to facilitate a range of uses such as forestry, farming and mineral extraction in order to foster economic development and generate employment whilst approving development that protects the environment and amenity for the community and visitors. The strategy also provides for consideration of cultural and social interests. The proposal to utilise two existing borrow sites to extract minerals to strengthen the Lake Rowallan Dam embankment. This is a small component of the larger project that is supporting the local community by: • ensuring critical infrastructure remains sound into the future; • providing employment for contractor employees and in support industries; • injecting investment into local shops and businesses; and • ensuring that the construction work does not compromise safety on local roads. Therefore it is evident that the proposal is consistent with the Meander Valley rural strategy. 1.8.3 Settlement, Use and Development Strategies (21) Mineral Extraction Strategy This provision encourages the development of mineral resources where conservation, scenic, amenity and road access concerns can been addressed. This report demonstrates that each of the above concerns can be effectively managed while at the same time allowing for the development to proceed.

PART TWO – PLANNING CONTROLS 2.1 Regulation of the Use, Development, Protection and Conservation of Land Development and use of mineral resources (quarry) is defined in the scheme as Industry Low/ Medium/ High Impact. This is a Discretionary use in the Rural zone RU1 and will therefore require a permit. 2.2 Application for a permit 2.2.1 The mining lease and quarry development is situated wholly on Crown Land that is designated as State Forest and as such is managed by Forestry Tasmania. The Bass District Forest Manager has been notified of the mining lease and the submission of this proposal and has suggested a compensation agreement that is satisfactory. A copy of a Memorandum of Understanding accompanies this application. 2.2.1 State Policy on Water Quality Management. Water quality has been considered in detail in Part C Section 6 of this report. 2.3 Use or Development in zones



2.3.1 The proposed use (quarry) is categorised as Industry Low/ Medium/ High Impact. 2.3.2 and 2.6 Industry is Discretionary in the RU1. 2.10 Consideration of an Application for a permit Before granting, either conditionally or subject to conditions on, or refusing a permit for a use or development, Council shall take into consideration:

Standard Response

a) The Goal and objectives of the scheme, settlement, use and development strategies, zone intent and policies, relevant development standards and other relevant considerations of the scheme.

Refer to PART ONE above for strategic consideration. Refer below for zone intent and other relevant standards.

b) Any relevant proposals, reports or requirements of any persons

See Appendix 2 Botanical Survey and Fauna Habitat Assessment, Appendix 3 Weed and Plant Pathogen Management Plan, and Appendix 5 Archaeological Report Review Form.

c) Whether the land is subject to a range of hazards.

Erosion protection is discussed in Part C Section 6 of this report and in Appendix 4 Rainfall Runoff Calculations

d) Whether the proposed use and development is satisfactory in terms of its siting, size or appearance and levels of emissions.

A description of the site is included in Section 2. Adjoining land uses are discussed in Part B Section 2.2 Landscape impacts are discussed in Part C Section 16 Cultural significance is discussed in Part C Section 3 and Section 14. Relevant pollution or hazards are discussed in Part C Sections 4, 5, 6, 7 and 8.

e) Any provisions of Part 4 of the Scheme not listed in this clause

See general provisions Part 4 in this section.

f) Whether there is adequate provision of landscaping, amenity, facilities and illumination for the development, and the treatment of the site generally;

The treatment of the site for a quarry refers to retention of screening vegetation in part c section 16 and rehabilitation in section 17.

g) Whether the proposed use or development will adversely affect the existing and planned future use of adjacent land, and vice versa;

The final use of the development areas is discussed in Part C Section 17.

h) Whether the proposed development will be supplied with an adequate level of infrastructure and services without detriment to existing uses;

The requirement for off-site infrastructure and impacts is discussed in Part C Section 10.

i) Whether the proposed use or development is adequately served by roads

The effect on the existing road network is discussed in Part C Section 9. and below.

j) Whether the assessed impact of the proposed use or development is acceptable in terms of

A Traffic Management Plan is discussed in Part C Section 9.



road safety, amenity and efficiency k) The objectives of the RMPS The objectives of the RMPS largely relate to

sustainable and strategic development that provides social and economic development while ensuring safety and protecting the environment. This proposal demonstrates consistency with these objectives.

l) The circumstances of the case and the public interest; and

See Part 1 of the Planning Scheme discussion

PART THREE – ZONING PROVISIONS 3.6.Rural zone (RU1) 3.6.1 Zone Intent The current planning scheme maps show that the borrow sites are situated on land zoned rural. The planning scheme states the intent of the rural zone is:

“(1) To provide for the use and development of the physical, economic, conservation and cultural resources of the Rural zone and the activities that support this primary purpose.

(2) To ensure the protection of access to and sustainable development of resources and provide appropriate processes for resolving competing interests.

(3) Rural zone is to conserve:

(a) resources for economic development; ...”

(Meander Valley Council, 1995)

The intended activity is consistent with the intent of the zone. No zone that may allow a conflicting sensitive use is located anywhere near the site. The most common sensitive use that is affected by an operating quarry is residential use. Residential development is prohibited in the rural zones in the planning scheme unless the residence is integral to an agricultural use.

3.6.2 Zone Policies (2) This policy is proposed to facilitate forestry and mining activities in appropriate locations. The proposal is for a quarry and borrow which are considered to be a mining activity and is well screened by existing forestry and is more than 16 km from the nearest sensitive use. Therefore the proposal is consistent with the policy. (3) The proposal is consistent with the policy to conserve areas of scenic value whilst providing sustainable economic activity. This has been demonstrated in the discussions included in Part C Section 16. (5) Although the land is zoned Rural, it is an area that is set aside for forestry purposes. Previous extractive activities have rendered the land unsuitable for forestry operations. The land is not suitable for agricultural purposes therefore policies to develop new agricultural pursuits or limit forestry and mining industries are not relevant. Additionally, the proposal will not require Council to provide additional services and will not impose



on any corridors identified for future urban expansion. 3.6.3 Development requirements and Standards in the Rural (RUI) zone (1) No subdivision is proposed. (2) No permanent structures are proposed therefore height and setback standards are not relevant. PART FOUR - GENERAL PROVISIONS 4.1 - 4.4 The proposal is located in an unsewered area, however the development does not include structures that might require site services. Employees will utilise temporary facilities established for the major project. There will be no requirement to relocate boundaries or reorganise titles or any need for minor subdivision, therefore these standards are not applicable to this proposal. 4.5 Lake Rowallan is the source of the Mersey River, watercourse protection in accordance with WSUD principles has been incorporated into the design see Part C Section 6 and Appendix 4. 4.6 The proposal is for temporary extractive activities with immediate rehabilitation of the new disturbance. No permanent structures that may be affected by unstable land will result. 4.7 Contaminated land is discussed in Part C Section 12. 4.8 The land is subject to bushfire hazard however, given the proposal does not include buildings, this standard does not apply to this proposal. 4.9 The proposed location for the quarry and borrow are not located in a scenic protection area. However visual impact is discussed in detail in Part C Section 16. 4.10 The proposal is not located in a Karst area therefore this standard is not applicable. 4.11 The proposal does involve the removal of trees. Flora and fauna values are discussed in Part C Section 1 and in the Appendix 2 and Appendix 3. 4.12 Environmental emissions are discussed in Part C Sections 4, 5, 6, 7 and 8. This report has demonstrated that the proposal can achieve the emission standards proposed under the planning scheme. PART FIVE – CAR PARKING The proposal does not include any structures and will not involve the regular employment of any staff members, therefore this standard is not applicable. However, there will be large areas available for vehicles attending the site to undertake the expected intermittent activity. PART SIX – SIGNS No signs are proposed as part of this proposal other than those recommended to warn road users of heavy traffic movements and forest users of steep faces.



PART SEVEN – ITEMS OF CULTURAL SIGNIFICANCE There are no historic heritage sites or items on this site. However the area was identified as having potential for Aboriginal heritage values. An Aboriginal heritage values assessment was undertaken and the resulting report was assessed by Aboriginal Heritage Tasmania. The report’s recommendations guided the design of clay borrow A. PART EIGHT The description of the use and development is included in Part 1 and 2 of this section.

2.3 LAND TENURE The rock quarry is located to northwest of the Lake Rowallan Dam and the clay borrow is located to the southeast. The rock quarry is situated on the side of the access road to the dam and wholly within State Forest and the clay borrow area may be located partly within the inundated area of the lake. The water level will be reduced by 20 metres to facilitate this work. The land below FSL of Lake Rowallan is vested in the Hydro Electric Corporation so the clay borrow may be partly located on State Forest and partly on Hydro Tasmania vested land.

Table 3 provide land tenure details and Figure 1 shows the location of the main operational areas.

TABLE 3: PROJECT AREA DETAILS

Project Name Lake Rowallan Dam – Borrow Areas

Address Mersey Forest Road, Mersey Forest

Above TWL Land owner State Forest managed by Forestry Tasmania

Property ID 2530822

This parcel is untitled Crown Land of some 795 000 hectares

Below TWL Land owner Vested in Hydro Electric Corporation

LPI GFJ58

Meander Valley Planning Scheme 1995 Land Parcel is Zoned ‘Rural’

The arrangement of the cadastral parcels is displayed in Figure 2 Region Plan – Cadastre.



FIGURE 1: LOCALITY PLAN - EXTRACT FROM 1:100,000 SERIES TOPOGRAPHIC MERSEY 8114

2.4 GEOLOGY The site of Lake Rowallan has two dominant geological types. The southern portion and higher in the landscape is comprised of lower glacio-marine sequences of mudstone, pebbly-mudstone, pebbly-sandstone, minor limestone and Tasmanite-oil-shale. The northern portion consists of undifferentiated politic rocks and quartzite sequences, with green schist facies metamorphism. The only exception to this sequence is the occurance of glacial, peri-glacial and fluvioglacial sediments including till and interglacial deposits along the eastern shoreline where the Fish River enters Lake Rowallan.

2.5 GEOMORPHOLOGY The banks of Lake Rowallan north from the inflow of the Mersey River to level with Howells Bluff are steep with a reservoir graded shape that has reached an unstable equilibrium. Fluctuations in lake level can cause land-slips in these banks that may result in further slumps or instigate erosion.

Clay borrow A

Lake Rowallan Dam

Rock quarry 2

Howells Bluff

Fish River 2681

2700

2702

Geo-Heritage Sites

Quarry 1



On the shoreline further north the Fish River inflow on the eastern bank has caused a braided delta to form at the foreshore. The braided delta is perched on a slight shelf and is unconsolidated and likely to become mobile if disturbed. The Fish River Alluvial Fan is registered as geo-heritage site ID 2681. This feature is vulnerable to wave action, excavation, vehicular tracks and variation in flows in the Fish River.

Further north towards the embankment wall the banks on the eastern and western side become steeper although some flatter sections exist on the eastern side. Clay borrow is one such flatter section. At the dam wall the last glacial till and fluvioglacial deposits overlie similar deposits of an earlier glaciation. This feature is registered as Mersey River Overflow Channel Glacial Deposits, ID 2700.

To the east of the operations areas part of an end moraine complex of the Mersey Glacier stretches between Dublin Bog and upslope towards Clumner Bluff. This feature is registered as Mersey Valley Latero-terminal Moraine, ID 2702. The entire area is listed the Central Highlands Cainozoic Glacial Area ID 2953.

(Hydro Tasmania Consulting, Nov 2009)

TABLE 4: CLIMATE DATA

Climate data for nearest weather station (with a complete record) – temperature and rainfall - Moina (091064)

Mean max. Temperature (0C) 13.9 Mean min. Temperature (0C) 3.4

Mean annual rainfall (mm) 1785

Climate data for nearest weather station (with a wind data record) – Wind data - Erriba (091119)

Wind data At the nearest weather station 091119 the predominant wind direction (30 % of the time) and the strongest winds between 30 and 40 km/hr come from the southwest. The strongest winds are recorded during winter. In summer a secondary and lighter wind direction is from the northeast.


Integrated Land Management and Planning | Map and Site Plan 18

2.6 DESCRIPTION OF THE RESOURCE The clay borrow areas are described in the original drilling report (dated 1959) as fluvioglacial filled depressions, saddles and banks overlying hard quartz mica schist. The filling is of varying thickness and consists of silts and clays with numerous predominantly dolerite (but with few quartzite) boulders, cobbles and pebbles. A recent set of test pits indicate that the selected area will produce the desired product but with up to 50% by volume wastage.

Quarry 1 is referenced in the Deposits Database as deposit number 7366. The deposit is described as having a resource potential of up to 1 000 000 tonnes of Road Sub-base produced from schist, extracted by dozer.

The quarry has extremely high faces and bedding planes of a metamorphosed rock close to vertical. Freeze thaw action on the joints between the planes has introduced instability into the benches. No extraction will take place at Quarry 1 due to the potential instability of the faces. The area will be used as a hard stand for materials, stockpiles and for a refuelling stand as for previous phases of the project.

Rock quarry 2 is referenced in the Deposits Database as deposit number 7378. The deposit is described as having a resource potential of up to 1 000 000 tonnes of sedimentary gravel extracted by blasting.

3 MAP AND SITE PLAN The Proponent is seeking to supply a project to strengthen the Lake Rowallan earth fill dam with clay and rock fill sourced locally. The anticipated borrow sites are those used for the original dam construction works. Construction materials from the original source are desirable;

• to maintain compatibility with the original embankment construction, • minimised clearing of native vegetation communities, • eliminate the need to cart quantities of heavy materials on the local road network, and • minimise the risk of road kill impacting on threatened native fauna species.

The strengthening works on the embankment are the subject of a separate approval process conducted by the Assessment Committee of Dam Construction (ACDC).

The two extraction sites are identified on the Local Plan Plan Figure 3 as is the transport route between the sites and the dam construction works site. It can be seen that cartage will occur for rock materials to either side of the dam and clay materials to either side of the dam.

FIGURE 2: REGION PLAN - CADASTRE

FIGURE 3: LOCAL PLAN - BORROW AREAS


Integrated Land Management and Planning | Map and Site Plan 21

3.1 MINING PLANS 3.1.1 CLAY BORROW A The surface of the clay borrow site will be stripped of vegetation and unsuitable organic materials. These materials will be windrowed above the Full Supply Level (FSL) of the lake and used in subsequent rehabilitation activities. Historic drilling and more recent test pits indicate that target clay resource is around 4 metres thick.

The resource will be direct excavated and processed using a grizzly and a mechanical screen. The grizzly will remove the >150mm nom. component and the mechanical screen will remove the >40mm nom. component leaving a silty clay with a gravel component. The final product will be stockpiled in a convenient location within the borrow area site or at the construction site.

The unsuitable material will be stockpiled temporarily until the required quantity of product is won and will then be placed back in the excavation to form a more natural landform and the basis for the rehabilitation effort. See Figure 4. Mining Plan clay borrow A in Appendix 1.

3.1.2 ROCK QUARRY 2 The extraction area will be stripped of vegetation leaving a strip of mature trees alongside West Rowallan Track. An existing access track leading from an adjacent clearing to the top of the existing face will be utilised to mobilise the drill rig onto the site of the first shot. The initial shot will enable a bench to be developed at approximately 5 metres above the existing quarry floor.

The shot rock will be pushed into the floor of the existing quarry, where the rock product will be sorted from the fines. The fines will be a well graded hard gravel product that will be suitable for road maintenance and reconstruction activities. A second and perhaps third shot will remove all but a 4 metre wide section of the bench resulting in a floor level contiguous with the existing. The remaining bench will intersect the existing face approximately where the natural recruitment vegetation is evident. The floor will grade gently towards the road and runoff will be collected in a sediment retention facility located close to the vegetation screen.

The proposed mining plan for the rock quarry is included as Figure 4 Mining Plan rock quarry 2 in Appendix 1.


Integrated Land Management and Planning | Rationale and Alternatives 22

4 RATIONALE AND ALTERNATIVES Dam construction techniques and standards are continually being improved and upgraded. An internal assessment by the Proponent found that although the dam was constructed to the standards at the time, upgrade work is required to ensure the dam meets current standards. The objective of the work to strengthen the embankment of the Lake Rowallan Dam is to ensure that the dam will continue to meet serviceability expectations into the future.

The design philosophy of the zoned earth fill embankment is to provide a low permeability core of compacted clay supported structurally with highly permeable rock fill on the upstream and downstream faces. In undertaking reconstruction work it is essential that the engineered materials are as homogenous as possible. This ensures that there are no zones weaker or more or less permeable that could become stress points and lead to future problems.

The rationale behind using the original sites to extract the construction materials is to ensure that the blend of the old and new will be as consistent with the existing as possible. Originally the sites were selected because the products had the right engineering qualities and they were close to the dam construction site. These aspects are important but now there are added benefits associated with sourcing the product close at hand.

The Lake Rowallan area has become an important region for tourism and recreation, with bushwalking, trout fishing, sightseeing and canoeing activities popular. It is therefore important to restrict the numbers of heavy vehicles that are required to use the narrow and treacherous roads leading to the site.

The roads leading to Lake Rowallan pass through forests that are habitat for various threatened species such as tasmanian devil, spotted tailed quoll and wedge-tailed eagle. These species are vulnerable to mortality through road kill. By recovering the materials from close to the site, the cartage distances are very short and the threat of road kill substantially reduced.

An alternative to purchase the appropriate materials from commercial quarries was considered but the advantages described above were seen to outweigh the extra effort required to apply for permits and leases to temporarily operate borrows and quarries


Integrated Land Management and Planning | Part C Potential environmental effects 23

PART C POTENTIAL ENVIRONMENTAL EFFECTS

1 FLORA AND FAUNA A botanical survey and fauna habitat assessment was undertaken by North Barker and Associates in December 2012. The work was commissioned during the summer to provide the best opportunity to identify any threatened species that may flower during spring and summer. At the time of the survey five sites were under consideration as construction material sources. Of these five sites only two will be developed for extraction. The two sites are referred to as Borrow A and Quarry 2 in the botanical survey and fauna habitat assessment.

The botanical survey and fauna habitat assessment found:

• No species listed under the Tasmanian Threatened Species Protection Act 1995 within the study areas.

• No species listed under the Commonwealth Environment Protection and Biodiversity Conservation Act 1999 within the study areas.

• It is highly unlikely that the activity will impact on any threatened flora or fauna species. • There were examples of two weed species listed as “declared” under the Tasmanian Weed

Management Act 1999 recorded within the study areas.

A key recommendation of the flora and fauna assessment was that a “weed and plant pathogen spread prevention plan” be undertaken to minimise the risk of the works spreading weeds or plant pathogens.

The Botanical Survey and Fauna Habitat Assessment Report is included as Appendix 2. The subsequent Weed and Plant Pathogen Management Plan is included as Appendix 3.

The status of wedge-tailed eagle nests located in the vicinity of the activities is being monitored for the dam strengthening works project. A wedge-tailed eagle nest is located in the vicinity of Rock Quarry 2 (see Local Plan Figure 3). The status of nest #863 in 2012 was not-active.

Blasting activities within quarry 2 will not commence until after the end of January 2014 and hence outside the sensitive period for breeding wedge-tailed eagles. Activities other than blasting will be similar to any other activities that are currently being undertaken as a normal course of the dam strengthening works. These activities are not likely to be perceived as strange or threatening.


Integrated Land Management and Planning | Rivers creeks wetlands and estuaries 24

2 RIVERS CREEKS WETLANDS AND ESTUARIES There will be no direct disturbance to a river, creek wetland or estuary by way of filling or impoundment. The expansion of the rock quarry will cause around 0.9 of a hectare of natural regrowth vegetation to be cleared. Run off from the cleared area will pass through retained vegetation before entering the roadside drainage in the first instance. Run-off from the disturbed ground in this area will be captured by the purpose built sediment retention facilities once the quarry has been developed.

Both the extraction sites are located within 200 metres of the normal shoreline of a river or lake.

Clay borrow A is on the edge of the normal shoreline of Lake Rowallan when the lake is at its FSL. The level of the lake will be low at the time of excavation due to the natural draw down of the lake. Excavation of the material may intrude into the normally inundated area.

The clay materials will be excavated from an area that, in its natural state is not stabilised and un-vegetated. The normal low level of the dam will expose a much larger area of this surface than will be exposed in the excavation.

The lake will not be spilling at the time of the works and the power generating decant tower restricts the flow downstream. Establishment of aquatic plant communities is supressed by the naturally brackish dark water and observations during recent low lake level events show that few aquatic communities would be affected by sediment emanating from the exposed shoreline.

The rock quarry is situated on the opposite side of the road to the bank of the Mersey River below the dam embankment. There is potential for sediments emanating from the rock quarry to be carried to the Mersey River via a pipe culvert under the road.

The first stage of the quarry development will include the development of a sediment retention basin located on the northern extremity of the existing quarry adjacent to Mersey Forest Road. The sediment retention basin will have capacity to detain sediment entrained runoff for a period to allow the suspended particles to settle out. The quarry floor will drain to the sediment retention basin via an existing shallow drain along the edge of Mersey Forest Road and a new drain to service the newly exposed area. See sediment retention facilities details on Figure 4 Mining Plan rock quarry 2 in Appendix 1.

The rainfall runoff management system described above was designed in accordance with the rainfall runoff calculations included as Appendix 4.

All the geo-conservation sites are located outside the area of disturbance for this project and will not be affected by the works. The region is mapped as being part of the Central Highlands Cenozoic Glacial Area recorded as ID 2953. The effect of the limited mining operation within the glacial deposits is not significant when the much broader effect of fluctuations in lake level is taken into consideration.


Integrated Land Management and Planning | Significant areas 25

3 SIGNIFICANT AREAS The Tasmanian Wilderness World Heritage Area (WHA) is a significant area and the Walls of Jerusalem Nation Park is an iconic destination within the WHA. It is necessary to drive past Lake Rowallan to access the terminus of the Walls of Jerusalem Walking Track. The activities at the dam will be visible from the road as will, to a lesser degree; the works on the lake foreshore at the clay borrow. Once on the walking track the activities will not be discernible even at elevation due to the distance and heavy forest cover. The works would be visible from Clumner Bluff but this feature is not serviced by a walking track.

The Mersey River White Water Reserve is an important recreation area for various canoe clubs and events are often held at this site. Using the white water reserve requires prior arrangements with the Proponent in order for water to be released from the dam to charge the rapids. It is not expected that there will be activity at the white water reserve.

Lake Rowallan is an important trout fishery and is popular early and late in the season when water temperatures are low. Access to the lake is problematic when lake levels are low. During the dam works the Proponent will maintain extremely low levels in the lake which will make access to the water’s edge difficult and hence the water unsuitable for fishing.

The Borrow area A site is a unregulated camping ground often used in the summer months by fishers and bush walkers. The activities at this site will present a safety risk to the public while the works are underway. It will be necessary to restrict public access for the duration of extractive activities and until the rehabilitation works have re-established a stable and uniform landform.

The Civil Works Contractor will post a sign on the side of Mersey Forest Road adjacent to the entrance to Clay Borrow A advising the public that the camp area is temporarily closed. A temporary barrier will be established to provide security.

4 MARINE AREAS The establishment of clay borrow A and rock quarry 2 in the vicinity of Lake Rowallan will not impact on marine areas.

5 AIR EMISSIONS Extractive activities can affect air quality through vehicle exhaust and dust emissions. Vehicle exhaust emissions are controlled through operating modern well maintained equipment.

Dust emissions can cause immediate effects through worker health and visual impacts and long term effects through the dust load on surrounding vegetation. The extractive operations will take place over a short duration period so the long term dust load will be negligible.

The activities at the clay borrow will occur with the extracted material in a moist state. It is highly unlikely that dust emissions will result from the excavation, screening or stockpiling of the clay materials.


Integrated Land Management and Planning | Liquid effluent 26

Activities undertaken at the rock quarry will include drilling, blasting, pushing and loading along with a small amount of rock breaking. These activities are known to cause dust emissions.

The drilling and blasting will be short duration activities, while the activities are underway there will be an amount of dust emitted but the overall dust load will be minimal over the duration of the works.

Dust emissions during pushing and loading are best controlled by keeping drop distances small. Trafficked surfaces will be maintained free draining to prevent mud forming that will dry to surface that is likely to emit dust.

If the transport task either to stockpile or to final placement occurs during dry periods, vehicle movements on the road may give rise to dust emissions. These tasks will be short duration activities so the overall dust load will not be significant. The short term effect may be on visibility on the road and as a result dust suppression will be required to ensure that vehicles can move safely.

6 LIQUID EFFLUENT The processes required to prepare the raw materials for use in strengthening the dam embankment will not require any liquid additives. As per the previous section dust suppression may be required. The effluent created by this addition will be managed through the rainfall runoff management facilities existing and proposed.

The mobile equipment utilised to win and cart the product will be refuelled either by a utility mounted refuelling facility or a designated refuelling facility. The same facility will be utilised to service the equipment utilised in the dam reconstruction part of the project.

The workers engaged in this portion of the project will use the temporary facilities established to accommodate the needs of the dam reconstruction workers.

7 SOLID WASTE There will be no waste by-products generated by the operation of the rock quarry or clay borrow area. All materials will be utilised; stripping from both sites will be used in the rehabilitation effort at the completion of the project. Any unused clay materials will be blended with the unsuitable materials and used to reconstruct a natural looking foreshore within clay borrow A. The rock materials will be either utilised in the dam wall reconstruction or undersized and fines will constitute a gravel product that will be utilised in maintaining the road during and after the works.

8 NOISE EMISSIONS The normally applied Standard Recommended Attenuation Distance (SRAD) for blasting is 1 kilometre (DPIWE, 1999). The nearest sensitive receptor is a residence at Liena which is over 16 kilometres away to the north. It is highly unlikely that any activity, even blasting will be discernible at that distance.

All other receptors including walkers and tourists will be transient and hence any noise impacts will be fleeting.


Integrated Land Management and Planning | Transport impacts 27

9 TRANSPORT IMPACTS Figure 3 Local Plan – Borrow Areas shows the cartage route for materials taken from the extraction / stockpile areas to the construction site. The dam embankment will be cut down on either side of the spillway; hence access for both clay and rock will be via either side of the dam.

Actual volumes of materials that will be carted to the embankment will depend on the quality and therefore usability of the materials recovered. There will be up to 8,000 cubic metres of clay and 10,000 cubic metres of rock carted to the construction site.

9.1 PREPARATION In the first instance, materials will be extracted and processed into stockpiles of products suitable for construction works and unsuitable materials stockpiled for future rehabilitation works. The construction materials will be stockpiled in various locations including; clay borrow A, rock quarry 2, quarry 1 and the dam embankment site. The unsuitable stockpiles will remain at the extraction sites.

The preparatory works will occur over the summer / autumn of 2014. If it is deemed necessary to relocate all the construction materials won a total of 18,000 cubic metres of product will be carted in 3 to 4 months. It is most likely that medium combination trucks (truck and trailers) will be used for the cartage effort. A medium combination carries around 22 cubic metres, therefore over 12-16 weeks between 68 and 51 loads per week can be expected. It is likely that the work will be undertaken using rotating shifts over a shorter period to take advantage of the longer days and better weather. It can be expected that at a maximum 19 loads will be carted per day. Maximum traffic movements for the period will be up to 38 per day.

9.2 EMBANKMENT RECONSTRUCTION The dam reconstruction work is time critical and will occur when an appropriate window is apparent. The dam embankment will be vulnerable for a period during this work and it is expected that materials will be carted round the clock when needed. This work will occur in the summer of 2014/15. A portion of the construction material will be stockpiled close to the construction site and carting for this material will not be required.

9.3 TRAFFIC MANAGEMENT During the preparation phase and construction phase it will be necessary to cart product over Mersey Forest Road. This leg of Mersey Forest Road is managed and maintained by Forestry Tasmania as a public access road. To ensure that any interaction with other road users occurs safely it will be necessary to plan and implement a Traffic Management Plan. There will be occasions where heavy vehicles are using the road frequently and other times when oversized equipment will be transported along the road.

It will be necessary to temporarily block traffic on West Rowallan Track to allow blasting to proceed. The Civil Works Contractor will engage a Blasting Subcontractor whose responsibility it will be to prepare and implement a Blast Management Plan (BMP). The BMP will provide details on when and where Blast Guards will be stationed to hold traffic.


Integrated Land Management and Planning | Other off-site impacts 28

10 OTHER OFF-SITE IMPACTS The only off-site impact resulting from the rock quarry and clay borrow areas part of the work will come about as a result of transporting potentially oversized equipment to the site. This may interrupt traffic on the approach roads for a short period.

11 HAZARDOUS SUBSTANCES AND CHEMICALS The extraction of rock from rock quarry 2 will be achieved using explosives. The successful contractor will engage a fully qualified and experienced explosives contractor to handle, transport, store and deploy the explosives for blasting.

The successful contractor will ensure that all the equipment utilised on the site is free from hydrocarbon leaks. Any accidental spills or leaks will be immediately contained and cleaned up using a proprietary spill kit.

12 SITE CONTAMINATION The sites utilised in this project have been utilised for previous works of a similar nature. There is no information or evidence to suggest that past activities have caused site contamination. There are some artefacts such as a fence and some drill rods remaining around the rock quarry 2 site.

13 SUSTAINABILITY AND CLIMATE CHANGE A factor contributing to the decision by the Proponent to take out mining leases and development permits to recover materials from close to the construction site was that there would be a significant greenhouse gas emission impact associated with importing materials from commercial quarries.

14 CULTURAL HERITAGE The areas that will be disturbed during the course of this project have been fully investigated for Aboriginal cultural heritage. The report generated as a result of this study has been presented to Aboriginal Heritage Tasmania (AHT). The recommendations of the Aboriginal Heritage Assessment final report were accepted by AHT have been incorporated into the proposal and now guide the location and extent of the clay borrow A (Entura - 61AA9, 2013).

AHT indicated acceptance of the report in an Archaeological Report Review Form completed and returned to Entura (AHT, 2013). A copy of the Archaeological Report Review Form is included as Appendix 5.

A report prepared to evaluate environmental risks associated with the dam strengthening works found three sites with historic heritage significance in the vicinity of Lake Rowallan. One site was the dam itself and this significance has been taken into account in planning the strengthening works. The two other sites are Rowallan Hut site and Pine Hut. These sites are well outside the area that will be affected by the proposal (Hydro Tasmania Consulting, Nov 2009).


Integrated Land Management and Planning | Sites of high public interest 29

15 SITES OF HIGH PUBLIC INTEREST There are a number of sites within the vicinity of the works that are of considerable interest to the public. The sites include the Lake Rowallan Dam from a scenic and historic perspective. The commencement of the Walls of Jerusalem Walking Track is of interest to bush walkers and the view field as seen from the walking track is an important consideration. Access to the walking track is along Mersey Forest Road and continuity of access is an important consideration in traffic management planning.

16 VISUAL IMPACT As stated in Section 3 Lake Rowallan is situated within a region that has an abundance of significant areas. Although the undertaking of the works will not impact on the significant areas as demonstrated by this document, the works can have a detrimental effect on the public’s enjoyment of those areas by impacting on views.

16.1 ROAD USERS An integral part of the planning for the Rock Quarry 2 and Clay Borrow A is the retention of screening vegetation. The effect of retaining this vegetation is that from the view point of road users travelling past the work sites it will be difficult to see a discernible change. The cross sections below are derived from LiDAR ground survey data with typical tree heights superimposed.

16.1.1 ROCK QUARRY 2 The rock quarry is at present a significant disturbance on the side of West Rowallan Track. West Rowallan Track would receive less traffic from tourists than the Mersey Forest Road. The retained tree screen will prevent direct observation of the expanded quarry when travelling south until close to the point where the current quarry is observed. From the opposite direction the disturbance will be noticed no sooner.

16.1.2 CLAY BORROW A The site of the clay borrow is largely not vegetated at present, see Plate 2. If the activities are discernible through the tree screen the appearance will not be significantly different to as it appears currently. As excavation proceeds the equipment will be operating lower in the pit and will be hidden from view.

16.2 WALKING TRACKS AND OTHER VANTAGE POINTS 16.2.1 WALLS OF JERUSALEM WALKING TRACK The Walls of Jerusalem walking track climbs steeply out of the Lake Rowallan Valley around the lower slopes of Howells Bluff. The view to the west back to Lake Rowallan is spectacular if a vantage point is available. Plate 3 gives an indication of the type of view possible from this track. If Rock Quarry 2 were visible it is located over 6 kilometres away. As the track continues to climb the lower slopes of Clumner Bluff interrupts the view to the northern end of Lake Rowallan.


Integrated Land Management and Planning | Visual impact 30

PLATE 3: LOOKING NORTHWEST FROM WALLS OF JERUSALEM TRACK

16.2.2 LOGGING COUPE ON CLUMNER BLUFF A logging coupe situated on the mid slopes of Clumner Bluff offers a vantage point to see Lake Rowallan and potentially Rock Quarry 2. The regenerating forest is at present immature providing a panoramic view of the lake. From this vantage point an intervening hill prevents direct observation of the rock quarry. (see Plate 4 below)

PLATE 4: LOOKING WEST FROM LOGGING COUPE BELOW CLUMNER BLUFF

Walters Lookout behind Rock Quarry 2


Integrated Land Management and Planning | Visual impact 31

00 60 130 10 460

480

470

90

490

500

40 30 20 120 70 110 100 80 50

FSL

Mersey Forest Road

Tree screen West Rowallan Track

450

460

455

470

465

Cross Section though Clay Borrow A in relation to Mersey Forest Road (see Figure 4 Appendix 1)

Cross Section though Rock Borrow 2 in relation to West Rowallan Track (see Figure 5 Appendix 1)


Integrated Land Management and Planning | Rehabilitation 32

17 REHABILITATION

17.1 CLAY BORROW AREA A The site of the clay borrow is an informal camping, fishing area and boat ramp that has developed in an ad hoc manner over years of use. The camping areas consist of three relatively level areas with few stones, informal fireplaces and a natural marsupial lawn. The boat ramp has not been formalised and is indistinct. The prevalence of large stones and cobbles on the normal water’s edge must make launching a boat difficult.

Following the construction phase of the project and once it is certain that no more clay will be required, the clay borrow will be rehabilitated. The stockpiled unsuitable material will be blended with any remaining clay reserves and the product used to fill the excavated areas to form a natural looking and free draining land surface. The larger boulders and stones will be used to fill the toe of the remaining batters as a foundation for gravel materials used for contouring. The maximum residual slope will be less than 1 in 3. These steeper sections will be revegetated with plants from the mix in Table 5 below.

In preliminary discussions with Inland Fisheries Service it has been agreed that the informal camping and boiat ramp use should continue. The extraction of clay materials will cause some realignment of the shoreline in this location. The works will not affect the camp sites and access to these sites will be maintained. It may be possible to incorporate an area in the re-contoured surface with a low grade that has few stones and cobbles protruding. This new surface will be more convenient for fishers to launch small boats.

The existing area has very sparse vegetation most likely as a result of repeated trafficking by vehicles and camping activities and forms a rocky ‘beach’. The areas more remote from the water’s edge are steeper not trafficable and well vegetated. Extraction of materials from the ‘beach’ may cause the water’s edge to encroach and reduce the beach area. Extraction will not proceed into the steeper area and hence the existing vegetation will not be disturbed. There will be no attempt to revegetate the small residual beach area as this will provide access to the camp sites and for launching boats.

TABLE 5: PLANTING SCHEDULE CLAY BORROW A REHABILITATION

Species Common Name Structure and location

Lomatia tinctoria guitar plant On re-contoured batters.

Pultenaea juniperina prickly beauty On re-contoured batters.

Poa labillardierei silver tussockgrass On re-contoured batters

Juncus astreptus rigid rush On re-contoured batters

See rehabilitation plan Figure 6 in Appendix 1 for the proposed final layout of clay borrow A.


Integrated Land Management and Planning | Part D – Management commitments 33

17.2 ROCK QUARRY 2 Rock quarry 2 is ideally situated to provide a hard stand area for future works on the Lake Rowallan Dam. Rehabilitation works for this site will concentrate on supporting and expanding the natural revegetation that has taken place on the southern extremity of the main face.

The new face will be divided into two faces approximately 5 metres high separated by a substantial bench around 4 metres wide. The faces will be ripped to ensure that the exposed surface is stable and materials stripped from the footprint of the quarry will be placed along the bench. The stripped vegetation will contain viable seed. This combined with seed blown in from the surrounding forest will promote natural re-colonisation by local provenance plants.

The natural recruitment of shrubs and trees will be supplemented with the distribution of seed and direct planting of species selected from the local provenance plants to quickly stabilise the surfaces and start to conceal the exposed faces. The seeds and plants will be selected from the planting schedule presented below as Table 6.

The floor of the quarry will remain a gravel surface and the drainage introduced to control run-off during operations will remain in place. These low grade drains will keep flow velocities low which will prevent scouring. Once extraction, recovery and rehabilitation activities are complete there will be little or no traffic on the surface to liberate silts and sands. The sediment retention facilities will quickly become redundant once the quarry floor surface is stable.

See rehabilitation plan Figure 6 in Appendix 1 for the proposed final layout of the quarry 2 area.

TABLE 6: PLANTING SCHEDULE ROCK QUARRY2 FACE REHABILITATION

Species Common Name Structure and location

Eucalyptus amygdalina black peppermint Upper storey, quarry floor against first face.

Eucalyptus delegatensis whitetopped stringybark Upper storey, quarry floor against first face.

Eucalyptus pauciflora cabbage gum Upper storey, quarry floor against first face.

Acacia melanoxylon blackwood Upper storey, quarry floor against first face.

Acacia dealbata silver wattle Mid-storey, quarry floor against first face.

Pittosporum bicolor cheesewood Shrubby understorey on bench and against face.

Hakea lissosperma mountain needlebush Shrubby understorey on bench and against face.

Lomatia tinctoria guitarplant Shrubby understorey on bench and against face.

Pultenaea juniperina prickly beauty Shrubby understorey on bench and against face.

Dianella tasmanica forest flaxlily Low herb on the bench and against face.

Lomandra longifolia sagg Ground cover sedge on bench and against face.



PART D – MANAGEMENT COMMITMENTS Number (Section)

Commitment Completion By whom

1

(Part C Section 1)

Blasting activities within quarry 2 will not commence until after the end of January 2014 and hence outside the sensitive period for breeding wedge-tailed eagles.

Prior to works commencing

Civil Works Contractor / Blasting Contractor

2

(Part C Section 2)

Sediment retention facilities will be installed at rock borrow 2 to ensure that any run-off is detained long enough to allow suspended particles to settle out. The facilities will be designed to control a 1 in 10 year reoccurrence event.

Prior to extraction from lower bench

Civil Works Contractor

3

(Part C Section 3)

A sign will be posted on the side of Mersey Forest Road adjacent to the entrance to Clay Borrow A advising the public that the camp area is temporarily closed. A temporary barrier will be established to provide security

Prior to works commencing


4

(Part C Section 5)

In the event that dust emissions are excessive a water cart will be used to wet down surfaces including quarry floors, stockpiles and connecting access roads.

Ongoing during extraction


5

(Part C Section 6)

The equipment used in the extractive operations will be refuelled from the same refuelling facility utilised for the major contract works.

Ongoing during extraction


6

(Part C Section 7)

Rubbish, spare parts and packaging will be contained within sealed containers and transported off-site to a recycling facility or refuse disposal site as required.

Ongoing during works


7

(Part C Section 9.3)

A Traffic Management Plan will be implemented to ensure appropriate signage is erected and to impose a blanket speed reduction for those periods when the project is active.



8

(Part C Section 9.3)

A Blast Management Plan will provide details on when and where Blast Guards will be stationed to hold traffic before any blast occurs.

Prior to blasting




Number (Section)

Commitment Completion By whom

9

(Part C Section 11)

Explosives will be handled by a fully qualified and experienced explosives contractor. All transport, storage and handling of explosives will be in accordance with Explosives Act 2012 and Explosives Regulations 2012.

During blasting activities


10

(Part C Section 11)

If a refuelling facility is used for the extractive activities part of the contract the facility will be established in accordance with AS 1940 – 2004.



11

(Part C Section 11)

A hydrocarbon spill kit will be retained onsite whilst mobile equipment is in operation and will be available for immediate deployment.




Integrated Land Management and Planning | Part E – Public consultation 36

PART E – PUBLIC CONSULTATION The Proponent has undertaken significant public consultation as part of the preliminary planning for this work. Stakeholders and interested parties already consulted include:

• Forestry Tasmania • Inland Fisheries Service • Parks and Wildlife Service • Meander Valley Council • Environment Protection Authority • Mineral Resources Tasmania

As required under the Land Use Planning and Approvals Act 1993 the Proponent is required to submit a Development Application to the Planning Authority. This document will be provided with the Development Application as supporting information to enable interested parties and stockholders to evaluate the proposal.

Under the Meander Valley Planning Scheme the Land Use Zoning of the land classifies extractive activities as a ‘discretionary’ use. The Development Application will therefore be advertised to the public who will have a period to consider the submission and lodge representations.

REFERENCES

AHT. (2013). Archaeological Report Review Form - Rowallan Dam Upgrade Investigations. Hobart: unpublished.

BOM. (2013, July 25). Daily Rainfall - Mole Creek. Retrieved July 25, 2013, from Climate Data Online: http://www.bom.gov.au/jsp/ncc/cdio/weatherData/av?p_nccObsCode=136&p_display_type=dailyDataFile&p_startYear=2011&p_c=-1658638777&p_stn_num=091065

DPIWE. (1999). Quarry Code of Practice. Hobart: Department of Primary Industries, Water and Environment.

Entura - 61AA9. (2013). Rowallan Dam Upgrade Environmnetal Investigations. Sydney: Hydro-Electric Corporation.

Hydro Tasmania Consulting. (Nov 2009). Rowallan Dam Upgrade - Preliminary Environmnetal Risk Assessment. Hobart: unpublished.

North Barker Ecosystem Services. (Dec 2012). Proposed Borrow Pit and Quarries for Dam Refurbishment - Lake Rowallan. Hobart: unpublished.


Integrated Land Management and Planning | Appendices

APPENDICES

APPENDIX 1 MINING PLANS


Integrated Land Management and Planning | Appendix 2: Botanical Survey and Fauna Habitat Assessment

APPENDIX 2: BOTANICAL SURVEY AND FAUNA HABITAT ASSESSMENT


Integrated Land Management and Planning | Appendix 3 Weed and Plant Pathogen Management Plan

APPENDIX 3 WEED AND PLANT PATHOGEN MANAGEMENT PLAN


Integrated Land Management and Planning | Appendix 4: Rainfall Runoff Calculations

APPENDIX 4: RAINFALL RUNOFF CALCULATIONS


Integrated Land Management and Planning | Appendix 5: Archaeological Report Review Form

APPENDIX 5: ARCHAEOLOGICAL REPORT REVIEW FORM

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