land and agricultural resource assessment

SLR Ref: 630.12468.001-R02 Version No: -v1.0 November 2020

CENTENNIAL MANDALONG

LAND AND AGRICULTURAL RESOURCE ASSESSMENT

LW30-LW33

Prepared for:

Centennial Mandalong

Centennial Mandalong Land and Agricultural Resource Assessment Extraction Plan LW30-LW33

SLR Ref No: 630.12518.001 November 2020

PREPARED BY

SLR Consulting Australia Pty Ltd ABN 29 001 584 612 10 Kings Road New Lambton NSW 2305 Australia (PO Box 447 New Lambton NSW 2305) T: +61 2 4037 3200 E: [email protected] www.slrconsulting.com

BASIS OF REPORT

This report has been prepared by SLR Consulting Australia Pty Ltd (SLR) with all reasonable skill, care and diligence, and taking account of the timescale and resources allocated to it by agreement with Centennial Mandalong (the Client). Information reported herein is based on the interpretation of data collected, which has been accepted in good faith as being accurate and valid.

This report is for the exclusive use of the Client. No warranties or guarantees are expressed or should be inferred by any third parties. This report may not be relied upon by other parties without written consent from SLR.

SLR disclaims any responsibility to the Client and others in respect of any matters outside the agreed scope of the work.

DOCUMENT CONTROL

Reference Date Prepared Checked Authorised

630.12518.001 November 2020 Michelle Papenfus Murray Fraser Rod Masters



CONTENTS

1 INTRODUCTION .......................................................................................................... 6

1.1 Assessment Objective ....................................................................................................... 7

2 AGRICULTURAL AND WATER RESOURCES ................................................................... 9

2.1 Climate .............................................................................................................................. 9

2.2 Topography ....................................................................................................................... 9

2.3 Hydrology .......................................................................................................................... 9

2.3.1 Surface Water ................................................................................................................................................. 9

2.3.2 Groundwater ................................................................................................................................................ 12

2.3.3 Licenced Surface Water Users ...................................................................................................................... 12

2.3.4 Licenced Groundwater Users ....................................................................................................................... 12

2.4 Geology ........................................................................................................................... 13

2.5 Soil Landscape Units ....................................................................................................... 13

2.6 Dominant Soil Types and Inherent Fertility .................................................................... 15

2.7 Acid Sulphate Soils .......................................................................................................... 17

2.8 Vegetation and Land Use ................................................................................................ 17

2.9 Land and Soil Capability Assessment .............................................................................. 18

2.10 Biophysical Strategic Agricultural Land ........................................................................... 21

3 LOCAL AND REGIONAL AGRICULTURAL ENTERPRISES ............................................... 22

3.1 Regional Agricultural History .......................................................................................... 22

3.2 Agricultural Enterprises and Associated Industries ........................................................ 22

3.2.1 Regional Land Use ........................................................................................................................................ 22

3.2.2 Regional Employment .................................................................................................................................. 23

3.3 Regional Agricultural Production Value .......................................................................... 24

3.4 Potential Agricultural Production Value of the Study Area ............................................ 24

3.5 Regional Agricultural Support Infrastructure ................................................................. 25

4 ASSESSMENT OF POTENTIAL IMPACTS ..................................................................... 27

4.1 Land Resources ............................................................................................................... 27

4.1.1 Land Temporarily Removed from Agriculture .............................................................................................. 27

4.1.2 Land Permanently Removed from Agriculture ............................................................................................. 27

4.1.3 Acid Sulfate Soils .......................................................................................................................................... 28

4.1.4 Impact on Biophysical Strategic Agricultural Land ....................................................................................... 28



CONTENTS

4.2 Water Resources ............................................................................................................. 28

4.2.1 Surface Water ............................................................................................................................................... 28

4.2.2 Groundwater ................................................................................................................................................ 28

4.2.3 Water Reallocation ....................................................................................................................................... 30

4.2.4 Water Resource Impacts on Agricultural Productivity ................................................................................. 30

4.3 Impact on Agricultural Resources from Biodiversity Offsets .......................................... 30

4.4 Other Impacts ................................................................................................................. 30

4.4.1 Visual Amenity and Landscape Values ......................................................................................................... 30

4.4.2 Tourism......................................................................................................................................................... 30

4.4.3 Weed Management and Biosecurity ............................................................................................................ 31

4.4.4 Air Quality ..................................................................................................................................................... 31

4.4.5 Noise............................................................................................................................................................. 31

4.4.6 Blasting ......................................................................................................................................................... 31

4.4.7 Traffic ........................................................................................................................................................... 32

4.4.8 Farm Fencing ................................................................................................................................................ 32

4.4.9 Farm Dams ................................................................................................................................................... 32

4.4.10 Impact on State Forest ................................................................................................................................. 32

4.5 Agricultural Regional Community Impacts ..................................................................... 32

5 MITIGATION MEASURES AND MANAGEMENT STRATEGIES ...................................... 33

5.1 Soil Resources ................................................................................................................. 33

5.2 Farm Fencing ................................................................................................................... 33

5.3 Ponding ........................................................................................................................... 33

5.4 Farm Dams ...................................................................................................................... 34

6 KEY FINDINGS .......................................................................................................... 35

7 REFERENCES ............................................................................................................. 36



CONTENTS

DOCUMENT REFERENCES

TABLES

Table 1 Soil Landscape Units ..................................................................................................... 13 Table 2 Dominant Soil Types and Inherent Fertility ................................................................. 15 Table 3 Land and Soil Capability Areas ..................................................................................... 18 Table 4 Lake Macquarie LGA Agricultural Land Use ................................................................. 23 Table 5 Employment in Agriculture .......................................................................................... 23 Table 6 Regional Agricultural Production ................................................................................. 24 Table 7 Potential Gross Margin per LSC Class ........................................................................... 25 Table 8 Gypsum Application Rates ........................................................................................... 33

FIGURES

Figure 1 Site Location ................................................................................................................... 8 Figure 2 Topography and Hydrology .......................................................................................... 10 Figure 3 Slope Analysis ............................................................................................................... 11 Figure 4 Soil Landscape Units ..................................................................................................... 14 Figure 5 Soil Types ...................................................................................................................... 16 Figure 6 Land and Soil Capability ............................................................................................... 20 Figure 7 Potential Grazing Area ................................................................................................. 26 Figure 8 Potential Remnant Ponding ......................................................................................... 29

PHOTOS

Photo 1 Eucalypt wooded area on a steep slope within the Study Area (SLR, 2018) ............... 17 Photo 2 Eucalypt wooded area on a plateau within the Study Area (SLR, 2018) ...................... 18 Photo 3 Mature Parramatta Grass……… .................................................................................... 31 Photo 4 Giant Parramatta Grass seed head .............................................................................. 31

APPENDICES

Appendix A Soil Landscape Unit Descriptions



SLR Consulting Australia Pty Ltd

1 Introduction SLR was engaged by Centennial Mandalong Pty Ltd (Centennial Mandalong) to complete a Land and Agricultural Resource Assessment over the Extraction Plan Application Area for Longwall (LW) 30 – LW33 (the Study Area) which covers approximately 330 hectares. In addition to the four longwall panels (LW30-LW33) the Study Area includes the limit of subsidence defined by the 26.5⁰ angle of draw from the longwall voids.

Mandalong Mine is a modern underground longwall operation located on the western side of Lake Macquarie near Morisset and west of the M1 Motorway (Figure 1). The Mine is situated approximately 130 kilometres north of Sydney and 50 kilometres from the Port of Newcastle, suppling up to six million tonnes of coal to the domestic power and export markets.

Mandalong Mine is owned and operated by Centennial Mandalong, a subsidiary of Centennial Coal Company Limited (‘Centennial’). Centennial completed the purchase of Mandalong Mine in August 2002. Centennial was subsequently purchased by Banpu Public Company Limited (Banpu) in October 2010.

Mandalong Mine commenced longwall mining in 2005 and operates narrow longwall panels in the West Wallarah Seam that utilise the bridging effect of the overlying massive strata to provide reduced levels of subsidence. This design is proven and provides subsidence impacts below safe, serviceable and repairable (SSR) criteria for dwellings and minimises the impacts to the Mandalong valley flood plain, natural features and surface infrastructure.

Centennial Mandalong currently operates under Development Consent approval SSD-5144. The Mandalong Southern Extension Project development application SSD-5144 was approved by the Planning Assessment Commission (PAC) on 12 October 2015 pursuant to Section 89E of the Environmental Planning and Assessment Act 1979 subject to conditions in Schedules 2 to 6. This Land and Agricultural Resource Assessment has been developed for the Extraction Plan in accordance with the requirements of SSD-5144 for the extraction of LW30-LW33 (the Project).

The specific consent conditions relating to this Land and Agricultural Resource Assessment taken from Development Consent SSD-5144 are:

• No loss of agricultural productivity greater than minor.

• Soil erosion assessment, which recommends measures to avoid, mitigate and otherwise respond to increased soil erosion (including tunnel erosion) impacts.

• Rehabilitation of disturbed areas including spreading of stockpiled topsoil in accordance with commitments in the EIS, revegetation using locally occurring native plant species, and rehabilitation of disturbed land to a condition that is self-sustaining or where maintenance requirements are consistent with the agreed post-mining land use.




Most of the surface of the proposed mining area is private land holdings with some Forest NSW (Olney State Forest) areas to the south and north-west of LW30. Properties located within the Study Area are typically rural residential properties of between fourteen and fifty-six hectares.

Within the Study Area there are fifteen properties, of which two are owned by Centennial Coal, two by the Forest NSW, one by the Central Coast Council, one Crown Land property and nine properties privately owned, as shown on Figure 1. There are six privately owned dwellings which may potentially be impacted by subsidence, two of the six residences (35 and 109) will be directly undermined by LW30-33.

1.1 Assessment Objective

The objective of this Land and Agricultural Resource Assessment is to outline the monitoring and management measures to be implemented to manage these potential subsidence related impacts on agricultural resources, specifically from the extraction of LW30-LW33.

This assessment will form part of an Extraction Plan being prepared by Centennial Mandalong for LW30-LW33 for submission to the NSW Department of Planning and Environment.

Lot180DP755238

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Study Area (LW30 - LW33)CadastreRoadTrack

OwnershipCentennial Central Coast CouncilCrown LandPrivate OwnershipState Forest

Study AreaMandalong Extraction Plan

LW30-LW33Sheet Size : A4

Project Number: 630.12518Date Drawn: 22-Oct-2020

FIGURE 1

Coordinate System: GDA 1994 MGA Zone 560 10.5

kmScale: 1:16,000 at A4

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Jilliby StateConservation Area

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Project Area




2 Agricultural and Water Resources

2.1 Climate

A continuous daily rainfall dataset was obtained as SILO Patched Point Data, which is based on historical data from a Bureau of Meteorology (BOM) station with missing data ‘patched’ in from interpolations from nearby stations. SILO data was obtained for the BOM Cooranbong (Avondale) Station (station number 61012) which is approximately 10 kilometres to the north-east of the Study Area. Daily rainfall records from January 1889 to December 2014 were used. The average annual rainfall for the area was 1,123 millimetres, with a range from 531 millimetres to 1,994 millimetres.

The BOM classifies the Study Area as being in a temperate climate zone with no designated wet season, although the area can be susceptible to occasional heavy showers and thunderstorms due to easterly troughs during warmer months. Summer winds are generally from the south or south-east, with a tendency for afternoon north-easterly winds. During winter, winds are predominantly from the south or south-west.

2.2 Topography

The Study Area is typified by relatively elevated densely timbered ridgelines surrounded by flat, low lying areas. Elevations on these ridgelines reach up to 260 metres Australian Height Datum (AHD) as shown in Figure 2. Limited relatively flat low-lying areas have been cleared for property development. The slope analysis (Figure 3) further highlights the ridgelines with slopes greater than 25% shown in red.

2.3 Hydrology

2.3.1 Surface Water

The majority of the Study Area lies within the broader catchment of Lake Macquarie, with the southern portion of the Study Area within the Wyong River catchment (Umwelt, 2020). The drainage channels associated with the LW30-LW33 Study Area include Buttonderry Creek and Morans Creek (Figure 2). All drainage channels within the Study Area are considered intermittent watercourses with limited or zero flow during low rainfall periods, suggesting that the number of users dependent on flows from these watercourses is limited (Umwelt, 2020).

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Study Area (LW30 - LW33)CadastreContourWatercourseRoadTrackState Forest

Topography & HydrologyMandalong Extraction Plan


Project Number: 630.12518Date Drawn: 16-Sep-2020

FIGURE 2



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Study Area (LW30 - LW33)CadastreWatercourseRoadTrackState Forest

Slope %0 - 1011 - 1515 - 2020 - 25>25

SlopeMandalong Extraction Plan



FIGURE 3



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2.3.2 Groundwater

The Water Management Plan (GHD, 2019) states the groundwater sources within the Study Area are predominantly within the Quaternary alluvium, weathered and/or fractured sandstone and coal seams.

Due to the relatively high silt and clay content of the alluvium, the groundwater sources are generally low yielding and are classified as ‘less productive’ according to the NSW Office of Water (NOW) NSW Aquifer Interference Policy (NOW, 2012), as the yields are generally less than five litres per second and/or the total dissolved solids concentration is typically greater than 1,500 milligrams per litre.

2.3.3 Licenced Surface Water Users

Due to the ephemeral nature of Morans Creek, the dependence of downstream water users on flows within these watercourses is expected to be very limited. GHD (2019) conducted a search of the NSW Water Register for surface water licences within a five kilometre radius of the Study Area. No surface water extraction licences were found within the Study Area.

Surface water licences were found for extraction from the Dora Creek water source of the Hunter Unregulated and Alluvial Water Sources Water Sharing Plan and the Jilliby Jilliby Creek Water Source Water Sharing Plan. The designated use or purpose of these licences includes irrigation, farming and industrial. No approvals for basic landholder rights were identified from GHD’s search of the NSW Water Register.

2.3.4 Licenced Groundwater Users

GHD’s (2019) search of the NSW Water Register for groundwater licences within a five kilometre radius of the Mandalong Mine found 140 registered groundwater bores.

The majority (64) are registered as monitoring or test bores, one bore is registered for monitoring/town water supply, 13 did not have a registered use, with the remainder (62) being registered for domestic, irrigation and/or stock use. The registered domestic and stock bores that were identified primarily extract groundwater from the Triassic sandstone and conglomerate formations with yields generally less than one litre per second.

Six private bores (GW201648, GW201649, GW201651, GW201652, GW201653) are located within one kilometre of LW30 to LW33, GHD (2019) found that all six bores are Mandalong Mine monitoring bores and not used for agricultural purposes.

A search of the NSW Water Register for groundwater licenses within a five-kilometre radius of the Study area found 17 registered groundwater bores of which the majority (10) are registered as monitoring or test bores and the rest as water supply bores.




2.4 Geology

The Study Area is in the south-western part of the Newcastle Coalfield, which occupies the north-eastern portion of the Sydney Basin. The coal seams found here are the Wallarah and the Great Northern, which together form the upper part of the Permian Newcastle Coal Measures.

Above the Wallarah and Great Northern Seams lies the Narrabeen Group, which are comprised of variable sequences of interbedded claystones, siltstones and fine to coarse-grained sandstones. The Munmorah Conglomerate is a sandstone-dominated formation within the Narrabeen Group, which typically occurs between 60 metres and 140 metres above the Newcastle Coal Measures.

2.5 Soil Landscape Units

The Soil Landscapes Units within the Study Area have been mapped by the former NSW Department of Land and Water Conservation, incorporating the NSW Soil Conservation Service (now part of NSW Department of Primary Industries (DPI)), on the Soil Landscapes of the Gosford – Lake Macquarie Sheet 1:100 000 Sheet (Murphy, 1993) shown in Figure 4. Four soil landscapes occur in the Study Area and are summarised in Table 1.

The majority of the Study Area which is on the Mandalong and Watagan Soil Landscape Units (84%) are highly to severely constrained for cultivation. Agricultural land best suited to grazing enterprises is represented by Gorokan and Woodburys Bridge which covers 16% of the Study Area.

Table 1 Soil Landscape Units

Soil Landscape Study Area Agricultural Limitation Rating

Unit Hectares % Grazing Cultivation

Mandalong 141 43 High – Severe High – Severe

Watagan 135 41 High – Severe High – Severe

Gorokan 54 16 Low High – Severe

Woodburys Bridge <1.0 <1.0 Moderate High – Severe

Total 330 100

Full descriptions of the four Soil Landscape Units within the Study Area are presented in Appendix A.

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Study Area (LW30 - LW33)RoadTrackCadastreState Forest

Soil LandscapesGorokanMandalongWataganWoodburys Bridge

Soil LandscapeMandalong Extraction Plan



FIGURE 4



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2.6 Dominant Soil Types and Inherent Fertility

The dominant soil types within the Study Area were assessed by SLR using the previous studies Soil and Land Resource Assessment Mandalong Southern Extension Project (GSSE, 2013), Soil and Land Resource Assessment Mandalong Transmission Line TL24 Relocation Project (SLR, 2017a) and determined using the Australian Soil Classification (ASC) System (Isbell, 2002). The key assessment points are listed below.

• Three major soil orders are present in the Study Area, Chromosols, Kurosols and Sodosols (Table 2 and Figure 5)

• Chromosols are soils with a strong texture contrast between the A horizon and a B horizon which is non-sodic and not strongly acidic. A Eutrophic Brown Chromosol comprises 41% of the Study Area

• Kurosols are soils with a strong texture contrast between the A horizon and strongly acidic B horizons. Many Kurosols have unusual subsoil chemical attributes such as high magnesium, sodium and aluminium. A Natric Brown Kurosol comprises 43% of the Study Area

• Sodosols are soils that have a strong texture contrast between the topsoil and subsoil horizons and contain sodic subsoil. A Mesonatric Brown Sodosol comprises 16% of the Study Area.

Kurosols range from moderately low to moderate inherent fertility, depending on ASC Great Group classification, with a Natric Kurosol (moderately low) occurring within the Study Area. The Sodosol has moderately low inherent fertility and the Chromosol has moderately high inherent fertility (Office of Environment & Heritage (NSW OEH, 2013).

Table 2 Dominant Soil Types and Inherent Fertility

Australian Soil Classification Inherent Fertility Hectares Percentage

Eutrophic Brown Chromosol Moderately High 135 41

Natric Brown Kurosol Moderately Low 141 43

Mesonatric Brown Sodosol Moderately Low 54 16

Total 330 100

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Soil UnitsSoil Type 2 - Woodbury's Bridge; Magnesic - Natric, Brown KurosolSoil Type 3 - Mandalong; Magnesic - Natric, Brown KurosolSoil Type 4 - Watagan; Eutrophic, Brown ChromosolSoil Type 5 - Gorokan; Mesonatric, Brown Sodosol

ASC Soil TypeMandalong Extraction Plan



FIGURE 5



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2.7 Acid Sulphate Soils

The likelihood of acid sulfate soils occurring within the Study Area is very low due to its position away from the coast and potential acid sulfate landform type. This is supported by the Lake Macquarie City Council (2012) Local Government acid sulfate soil maps. Furthermore, none of the Soil Landscape Units mapped within the Study Area have acid sulfate soil potential.

2.8 Vegetation and Land Use

Review of recent aerial images shows that the majority of the Study Area remains under native vegetation (approximately 85%), as shown in Photo 1 and Photo 2. A site inspection of adjoining LW25-LW31 in September 2018 by SLR’s Associate Agronomist Murray Fraser, in conjunction with a desktop assessment, has shown that small scale cattle and horse grazing of native grass species such as kangaroo grass (Themeda australis), Poa tussock (Poa labillardierei) and red grass (Bothriochloa spp.) is the dominant agricultural enterprise. No intensive cropping activities were observed at the time of the inspection and assessment.

Grazing within the Study Area appears to be commonly used as a grass and vegetation management tool rather than an income generating agricultural enterprise. Overall farm size is considered small and many would be classified as hobby farms with a very low potential to produce significant agricultural income. Approximately 15 hectares of potential grazing land is currently available for agricultural use.

Photo 1 Eucalypt wooded area on a steep slope within the Study Area (SLR, 2018)




Photo 2 Eucalypt wooded area on a plateau within the Study Area (SLR, 2018)

2.9 Land and Soil Capability Assessment

The LSC classification applied to the Study Area was in accordance with the OEH guideline The Land and Soil Capability Assessment Scheme; Second Approximation (NSW OEH, 2012). This scheme uses the biophysical features of the land and soil to derive detailed rating tables for a range of land and soil hazards. The scheme consists of eight classes, which classify the land based on the severity of long-term limitations. The Mandalong Mine site LSC assessment was conducted by GSSE (now SLR) in 2013.

Land within the Study Area has been classified into Land and Soil Capability (LSC) Classes 5 and 7, as listed in Table 3. Classes 5 and 7 comprised 54 hectares and 276 hectares of land within the Study Area respectively, as shown on Figure 6. The limitations associated with each LSC Class are discussed below.

Table 3 Land and Soil Capability Areas

LSC Class Agricultural Capability Rating Hectares Percentage

5 Moderately low 54 16

7 Very low 276 84

Total 330 100




LSC Class 5 Land

Class 5 land is represented by a Brown Sodosols. This classification indicates a moderate to low land capability, with severe limitations to high impact land management uses such as cropping. This land is generally more suitable for grazing with some limitations, or very occasional cultivation for pasture establishment. The limiting factor for LSC Class 5 within the Study Area is slope with sodic subsoil. It covers 16% of the Study Area.

LSC Class 7 Land

Class 7 land is represented by a Brown Kurosol and a Brown Chromosol. This classification indicates very low capability land, with extremely severe limitations for most land uses. It is generally unsuitable for any type of cropping or grazing due to its limitations. LSC Class 7 covers the majority of the Study Area (84%). The limiting factor for the LSC Class 7 land is shallow soil and steep slope.

Within the Study Area, 84% of the land area is considered to have very low agricultural capability according to definitions given in The Land and Soil Capability Assessment Scheme: Second Approximation (NSW OEH, 2012), whilst the remaining 16% has a moderately low agricultural capability.

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Land and Soil CapacityLimiting Class 5Limiting Class 7

Land and Soil CapacityMandalong Extraction Plan



FIGURE 6



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2.10 Biophysical Strategic Agricultural Land

According to the assessment parameters given within the Interim Protocol for Site Verification and Mapping of Biophysical Strategic Agricultural Land (NSW OEH, 2013), there is no Biophysical Strategic Agricultural Land within the Study Area, also with sodicity and slope being the limiting factors for the two LSC Classes it is highly improbable there would be any BSAL within the Study Area.

This is supported by the Soil and Land Resource Assessment Mandalong Southern Extension Project (GSSE, 2013) and the Biophysical Strategic Agricultural Land Assessment Mandalong Transmission Line TL24 Relocation Project (SLR, 2018) undertaken directly to the north and also overlapping into the Study Area, which found no qualifying BSAL.




3 Local and Regional Agricultural Enterprises

3.1 Regional Agricultural History

The Mandalong locality was settled in the mid 1850’s, with farming and timber cutting being the mainstays of employment. Farming consisted of cattle and sheep grazing and some crop growing. In the late 1800’s the timber industry declined and the poor soil could not sustain farming on a commercial scale. Mandalong is now regaining popularity as a hobby farming area (Lake Mac Libraries, 2020).

Within the Study Area, agricultural enterprises have traditionally been small farm enterprises conducted in pockets of cleared native bushland, reliant upon off-farm income to be sustainable. Cattle grazing, pleasure horse agistment and small orchard areas are the main agricultural activities in the area (Lake Mac Libraries, 2020).

3.2 Agricultural Enterprises and Associated Industries

3.2.1 Regional Land Use

The agriculture land uses for the Lake Macquarie and Central Coast LGA were taken from the Australian Bureau of Statistics (ABS) Census Data (2011 and 2018-2019) (ABS, 2020) and is displayed in Table 4. The major points are summarised below.

• Agriculture is a minor land use for the regional area, accounting for less than 1% in the Lake Macquarie LGA and less than 3% in the Central Coast LGA.

• Agricultural land is almost mostly used for grazing, utilising 55% and 70% of all agricultural land for the Lake Macquarie and Central Coast LGA respectively.

• Cropping enterprises comprise a very minor portion of agricultural activities. The primary crops grown are vegetables, fruit and other non-cereal crops.

• Minimal irrigation cropping is carried out with agriculture only a minor water user in the Lake Macquarie LGA, with 86 megalitres used for irrigation and an additional 66 megalitres utilised for other agricultural purposes, such as poultry and egg production. In the Central Coast LGA 3005 megalitres is used for irrigation and another 13 megalitres for other agricultural uses.




Table 4 Lake Macquarie LGA Agricultural Land Use

Classification Unit Lake Macquarie LGA Central Coast LGA

Agricultural Land Area (ABS, 2018-2019)

Total land area within LGA Hectares 64,020 185,600

Area of agricultural land Hectares 261 5,306

Proportion of agricultural land % 0.4 2.9

Agricultural Enterprise (ABS, 2018-2019)

Land mainly used for other agricultural purposes Hectares 87 180

Land under cropping activities Hectares 31 1353

Land under grazing activities Hectares 143 3752

Land mainly used for forestry Hectares NA 21

Proportion of agricultural land used for grazing % 55 71

Grazing Enterprises (ABS, 2018-2019)

Sheep, lambs and pigs Number 0 422

Meat cattle Number 144 1077

Milk cattle (excluding house cows) Number 12 0

Total Number 156 1,499

Cropping Enterprises (ABS, 2011 and ABS, 2018-2019)

Cereals for grain Hectares 0 39

Vegetables for human consumption Hectares 0.24 675

Orchard trees (including nuts) Hectares 5.5 369

All fruit (excluding grapes) Hectares 6.1 370

Total land cropped Hectares 11.8 1453

Irrigation (ABS, 2018-2019)

Irrigation volume applied Megalitres 86 3005

Other agricultural uses Megalitres 66 213

Total water use Megalitres 152 3218

3.2.2 Regional Employment

Agriculture is a very minor employer in the Lake Macquarie and Central Coast LGA, according to the ABS Agricultural Census Data (2020), which is the latest publicly available, there were 201,918 persons employed in the Lake Macquarie LGA and 159,111 persons in the Central Coast. Agriculture accounted for 0.6% of this total (1,066 people) as shown in Table 5.

The majority of persons employed in agriculture work in poultry farming and processing, horse farming, vegetable production and floriculture production.

Table 5 Employment in Agriculture

Employment Lake Macquarie Central Coast Total

Persons employed in LGA (number) 201,400 159,111 360,511 Persons employed in agriculture (number) 518 549 1,066

Percentage of persons employed in agriculture 0.27 0.34 0.30




3.3 Regional Agricultural Production Value

Agricultural production values for the Lake Macquarie and Central Coast LGA (ABS, 2016-2017) (ABS, 2020) totals $171 million per annum, as presented in Table 6. The main agricultural production by value is from livestock slaughtering and other disposals and nurseries and cut flowers.

Table 6 Regional Agricultural Production

Agricultural Production Gross Value Lake Macquarie LGA Central Coast LGA

Gross value % of total Gross value % of total

Nurseries, fruit and nuts $1,705,733 13 $69,194,945 44

Cut flowers $2,847,697 22 $5,814,815 4

Livestock products $3,904,792 31 $793,559 1

Livestock slaughtered and other disposals - Total $4,301,275 34 $82,461,415 52

Total gross agricultural production $12,759,496 100 $158,264,734 100

3.4 Potential Agricultural Production Value of the Study Area

Potential agricultural productivity was determined using NSW Department of Primary Industries (DPI) agricultural gross margin productivity data for agricultural enterprises suitable for each of the LSC classes (see Section 2.9) that are present within the Study Area. This analysis has been undertaken on the potential capability of the land rather than current land use. If potential agricultural production values were to be pursued, significant investment in land management and agricultural infrastructure would be required. However, this information can be used to approximate potential farm incomes.

The Beef Cattle Gross Margin Budget Coastal Weaners Improved Pasture (NSW DPI, 2017) has been applied to this assessment to determine potential agricultural income for the Study Area. The NSW Department of Primary Industries Beef Stocking Rates & Farm Size (NSW DPI, 2006) was used to determine stocking rates in Dry Sheep Equivalents (DSE) for the two LSC’s mapped within the Study Area.

Table 7 summarises the potential gross margins for each applicable agricultural enterprise per LSC Class. The major points are listed below.

• Class 5 land has the potential to generate approximately $158 per hectare from beef cattle grazing enterprises (yearling beef production).

• Class 7 land has the potential to generate approximately $79 per hectare from beef cattle grazing enterprises (yearling beef production).




Table 7 Potential Gross Margin per LSC Class

LSC Stocking Rate

Cow & Calf Equivalent Revenue Variable

Costs Gross

Margin Study Area

Available Area Gross Margin

Class DSE per Ha per Ha per Ha per Ha Hectares Value

5 4 0.24 $229 $70 $158 54 $8,588

7 2 0.12 $114 $35 $79 276 $21,835

Total 330 $30,423

Based on the nominated gross margins, and assuming the required agricultural capital costs and fixed costs are outlaid (not included in the calculations in Table 7), the Study Area has the capacity to generate an estimated gross margin of $30,423 per annum. It is important to note that these figures are derived from the optimum potential uses and are likely to be much higher than the actual incomes being achieved from the area under actual production.

It is expected that income generated from agricultural enterprises within the Study Area would be minimal due to the small area (15 hectares or 4.5% of Study Area) available for actual agricultural production (Figure 7). The majority of this cleared area is LSC Class 5 and using the gross margin information presented in Table 7, the 15 hectares available in the Study Area has a potential gross margin of $2,374 per annum.

3.5 Regional Agricultural Support Infrastructure

Agricultural support infrastructure within the Lake Macquarie and Central Coast LGA includes the Sydney-Newcastle M1 Motorway as the major arterial road, and rail infrastructure providing transport from agricultural areas in the west and north of the state.

The main purpose-built agricultural support infrastructure within the region are several large poultry sheds, which are used for raising meat chickens and egg production. There are several small retail agricultural suppliers that service the numerous hobby farms in the region. Outside of this, there is little formal infrastructure for the support of agricultural industries in the Lake Macquarie LGA.

Poultry processing is conducted outside the Lake Macquarie and Central Coast. The Inghams Enterprises poultry processing facility (abattoir) is located at Mangrove Mountain in the Gosford LGA, while other poultry processors are located at in the Newcastle LGA (Baiada Poultry), Cessnock LGA (Valley Feeds) and Blacktown LGA (Red Lea).

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Study Area (LW30 - LW33)Potential Grazing AreaRoadTrackCadastreState Forest

Potential Grazing AreaMandalong Extraction Plan



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4 Assessment of Potential Impacts The primary potential impact to agricultural resources is from subsidence. DGS (2020) predicts maximum vertical subsidence over LW30-LW33 to be 920 to 1,330 millimetres, given this and the predicted maximum tensile strains, crack widths are estimated to range from 20 to 140 millimetres wide where shallow or exposed rock exists. Wider cracks of up to 320 mm may occur on the upper slopes and at or behind slope crests. It is noted that surface cracking has been rare above the Mandalong mining panels to-date.

Surface cracking is unlikely to occur on areas of agricultural use, where deep soil or alluvium profiles exist, as the strain will be more uniformly distributed and absorbed. Surface cracks are ‘very unlikely’ to occur along creek beds (DGS, 2020).

4.1 Land Resources

4.1.1 Land Temporarily Removed from Agriculture

The proposed landform has the potential to cause or increase remnant ponding (ponding that occurs after prolonged rainfall and/or flooding) within the area affected by subsidence. Remnant ponding for the proposed landform is based on the predicted subsided landform associated with the new mine plan that includes LW30-LW33 (Umwelt, 2020).

Based on the Umwelt flood assessment for LW30-LW33 (2020) remnant ponding as a result of longwall subsidence will reduce to approximately 1.52 hectares from the EA pre-approval ponding area of 2.25 hectares (Umwelt, 2020).

The analysis indicates that potential impacts on remnant ponding are confined to existing flow paths, with no predicted impact on access routes to, or within, properties (and residences) within the Study Area. Where potential increases to remnant ponding are predicted or subsequently observed, local drainage works may be required to alleviate the increased ponding (Umwelt, 2020).

As LSC Class 5 is the most productive agricultural land within the Study Area, it is conservatively assumed all land impacted by remnant ponding is LSC Class 5. Using potential agricultural productivity information described in Section 3.4, the estimated positive economic impact on potential agricultural productivity as a result of reduced ponding is $115 over a 12 month period. When compared to the gross annual value of agricultural production for the Lake Macquarie and Central Coast LGA ($171 million), this temporary impact is on agricultural enterprises and associated industry is considered negligible.

4.1.2 Land Permanently Removed from Agriculture

There is no land which will be permanently removed from agriculture as a result of the Project.




4.1.3 Acid Sulfate Soils

As outlined in Section 2.7 there are no Soil Landscape Units associated with the Study Area with acid sulfate potential. The Project will not impact upon Acid Sulfate Soils.

4.1.4 Impact on Biophysical Strategic Agricultural Land

There is no mapped Biophysical Strategic Agricultural Land within the Study Area. The Project will not impact any Biophysical Strategic Agricultural Land.

4.2 Water Resources

4.2.1 Surface Water

The majority of the Study Area lies within the broader catchment of Lake Macquarie, with the southern portion of the Study Area within the Wyong River catchment. The Study Area intersects five sub catchment areas: Morans Creek, Wyee Creek and Mannering Creek catchments which flow to Lake Macquarie; and Buttonderry Creek and Jilliby Creek catchments which flow to the Wyong River. The Project will predominantly impact the Morans Creek catchment and a small portion of the upstream catchment of Buttonderry Creek (Umwelt, 2020).

Modelling shows very minor impacts to flood regimes and remnant ponding areas associated with the proposed landform relative to the approved landform. Impacts on the flow rates and annual flow volumes in Morans Creek would be negligible (or non-existent). Further, the watercourses within the Study Area do not have a long-term persistent baseflow. Their ephemeral nature is reflected in small flows during dry periods and cease to flow during drought periods. Any impacts to baseflows are expected to have negligible impacts on the streamflow conditions within these watercourses (Umwelt, 2020).

Based on the investigations by Umwelt (2020) and DGS (2020) as a result of the limited potential for changes to water quantities, including annual flow volumes, baseflows and environmental flows, downstream users are unlikely to experience significant changes to water availability due to the Modification 9.

Overall, it is considered that the Project will not result in adverse cumulative impacts on water use or flows in the areas surrounding the Study Area.

4.2.2 Groundwater

The predicted impacts on alluvial and fractured and porous rock groundwater sources as a result of mining at Mandalong Mine were found to be less than the Level 1 minimal impact considerations from the NSW Aquifer Interference Policy (GHD, 2019), therefore the Project will have negligible impact on groundwater resources relied upon by agriculture.

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Study Area (LW30 - LW33)RoadTrackState ForestPre-mining PondingPost mining Ponding ApprovedPost mining Ponding Proposed

Potential Remnant PondingMandalong Extraction Plan



FIGURE 8



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4.2.3 Water Reallocation

Mandalong Mine currently holds a water extraction licence (WAL 39767) for 1,825 megalitres utilised for mine dewatering, however this water would not be considered as being taken from potential agricultural use as the water is not considered suitable for general agricultural production. Mine dewatering occurs in the porous and fractured rock groundwater sources with typical electrical conductivity readings from 6,000 microsiemens per centimetre (μS/cm) to over 10,000 μS/cm (GHD, 2018) which according to Measuring Water Salinity (NSW I&I, 2009) is well above the desirable limit for healthy growth in cattle and horses, and suitable only for crops with a very high tolerance to saline water.

Centennial Mandalong does not intend to purchase any further surface or groundwater licences for the Project. There will be no impact on agricultural users through water reallocation.

4.2.4 Water Resource Impacts on Agricultural Productivity

Given the very limited impacts described previously, longwall subsidence will result in negligible impacts on water resources relied upon by agricultural enterprises and will not result in any impact on agricultural productivity.

4.3 Impact on Agricultural Resources from Biodiversity Offsets

The Project is not expected to result in the establishment of any biodiversity offsets; therefore there will be no impact to agricultural resources resulting from biodiversity offsets.

4.4 Other Impacts

4.4.1 Visual Amenity and Landscape Values

The Study Area lies within a landscape context of sloping ridgeline formations with moderate to dense tree cover and a high visual absorption capacity. Field inspection by SLR’s Associate Agronomist in 2018 did not identify any agricultural enterprises which were reliant upon visual amenity or landscape values as components of their operations. On this basis, the Project is considered to have negligible impact on visual amenity and landscape values relied upon by local and regional agricultural enterprises.

4.4.2 Tourism

The assessment has not identified any tourism infrastructure in the local area upon which agricultural enterprises are reliant. Therefore, the Project is not anticipated to impact on agriculture-related tourism.




4.4.3 Weed Management and Biosecurity

There is minimal risk from the introduction of weeds during the underground mining process. Weeds are managed within the framework of the Centennial Weed Management Plan, which includes issue-specific environmental management plans, such as weed control prior to any earthworks.

Giant Parramatta grass (Sporobolus fertilis) (Plate 4 and Plate 5) has previously been identified by a stakeholder as a weed with potential for concern. Where Giant Parramatta grass is identified on Centennial owned land, control will be undertaken with registered herbicides including glyphosate, 2,2-DPA or flupropanate.

Photo 3 Mature Parramatta Grass Photo 4 Giant Parramatta Grass seed head

Biosecurity is defined in the NSW Biosecurity Strategy 2013 – 2021 (NSW DPI, 2013) as ‘protecting the economy, environment and community from the negative impacts of pests, diseases and weeds’. It includes measures to prevent new pests, diseases and weeds from entering our country and becoming established. On a regional level, appropriate weed management will reduce biosecurity risks. Any import of equipment or machinery from overseas will follow the standard procurement safeguards and quarantine procedures as per Australian requirements. Given the processes above, there is negligible risk to the biosecurity of agricultural resources and enterprises within the region.

4.4.4 Air Quality

The Project involves the extraction of four underground longwall panels and as such there will be no impact to air quality resulting from the Project.

4.4.5 Noise

The Project involves the extraction of four underground longwall panels and as such there will be no impacts to agricultural production from noise generated by the Project.

4.4.6 Blasting

The Project does not involve any blasting as such there will be no impact to agricultural resources from blasting.




4.4.7 Traffic

The Project involves the extraction of four underground longwall panels with no increased traffic movements, and as such the impact to agricultural resources as a result of increased traffic movements is considered negligible.

4.4.8 Farm Fencing

Subsidence impacts of 0.2 – 1.3 metres on farm fencing could result in loss of tension or failure of wire strands and the possible failure of strainer posts. Swing gates could also be affected and not function properly after mine subsidence (DGS, 2020).

4.4.9 Farm Dams

Non-engineered farm dams and water storages may be susceptible to storage level changes due to mine subsidence (DGS, 2020).

It should be noted that farm dams have been subsided by underground coal mines elsewhere in NSW and any damage has been effectively managed. The dams were reinstated in a timely manner and an alternative supply of water was provided by the Mine during the interim period.

4.4.10 Impact on State Forest

There are several unsealed tracks and fire trails above the proposed longwalls, including The Olney State Forest and easement access roads and forestry access roads. Impacts due to the predicted subsidence may include tensile crack widths between 20 and 320 millimetres, compressive shearing or shoving between 20 and 160 millimetres, increase of super elevation in the road and cracking of culverts and fill embankments (DGS, 2020).

4.5 Agricultural Regional Community Impacts

No other impacts which may affect the regional agricultural community, resource or enterprises have been identified in this assessment.




5 Mitigation Measures and Management Strategies

This section describes the proposed mitigation measures and management strategies recommended to minimise potential agricultural impacts. Whilst the majority of impacts on agricultural enterprises and resources have been assessed as negligible, as a matter of best practice, Centennial Mandalong has adopted a number of mitigation measures to further minimise these impacts. A summary of key measures specifically in relation to potential agricultural impact is provided below.

5.1 Soil Resources

Where potential impacts have been identified gypsum will be applied for any remediation earthworks where sodic subsoils (exchangeable sodium is greater than 5%) are exposed. The application of gypsum will minimise the potential for tunnel erosion to occur on disturbed subsoil. The recommended application rates are shown in Table 8.

Table 8 Gypsum Application Rates

Exchangeable Sodium (ESP) Gypsum Rate per Hectare Gypsum Rate per Square Metre

5 to 10% 2 to 5 tonnes 0.2 to 0.5 kilograms

Greater than 10% 5 tonnes 0.5 kilograms

There are no soil stripping or stockpiling activities anticipated within the Study Area associated with the Project.

5.2 Farm Fencing

In the unlikely event of damage to fence tensioning or farm gate levels, Centennial Mandalong will remediate the damage in consultation with relevant stakeholders.

5.3 Ponding

The remnant ponding area for the pre-mining landform within the catchments of Morans Creek and Buttonderry Creek is 16 hectares. Within Longwalls LW30-LW33 the remnant ponding for the pre-mining landform is 2.25 hectares. Umwelt (2020) predicted compared to the pre-mining scenario, a decrease of 1.52 hectares in remnant ponding within Longwalls LW 30-33 (i.e. a decrease of 68%).

Property owners will be consulted as to whether they wish the additional ponding to remain or be remediated by Centennial Mandalong.




5.4 Farm Dams

Non-engineered farm dams and water storages will be susceptible to surface cracking and tilting (i.e. storage level changes) due to mine subsidence. The tolerable tilt and strain values for the dams would depend upon the materials used, construction techniques, foundation type and likely repair costs to re-establish the dam’s function and pre-mining storage capacity. All farm dams within the Study Area will be inspected by Centennial Mandalong for current water level and dam condition prior to and after mining. Should monitoring indicate potential for dam wall failure due to subsidence cracking, water will be transferred from the dam to a height that reduces the risk of dam wall failure. An alternate water supply will be provided to the owner until the dam can be reinstated (DGS, 2020).

In the event of subsidence damage to any farm dams, Centennial Mandalong will remediate the damage and reinstate the dam in consultation with relevant stakeholders.




6 KEY FINDINGS

This Land and Agricultural Resource Assessment has been prepared to be included in Centennial Mandalong’s Extraction Plan LW30-LW33. The purpose of this Land and Agricultural Resource Assessment is to assess and report on the potential impacts on agricultural resources within the Study Area and recommend mitigation measures to alleviate any identified impacts. The key findings are listed below.

• The majority of agricultural land use within the Study Area is for hobby farms and small cattle grazing areas, which are not major contributors to income generation. Grazing is mostly carried out as a land and vegetation management tool. Land available for agricultural land use comprises 4.5% of the Study Area.

• Post-mining agricultural economic potential in the Study Area is expected to be similar to pre-mining potential.

• The longwall mining will have negligible impact on surface and groundwater resources relied upon by agriculture (Umwelt, 2020 and DGS, 2020). Groundwater resources are predicted to be less than the Level 1 minimal impact considerations as per the NSW Aquifer Interference Policy (NOW, 2012).

• Any impacts resulting from longwall mining are expected to be minor and temporary and can be managed through application of appropriate mitigation measures and management strategies.

• Continuation of longwall mining by Centennial Mandalong will provide considerable positive economic benefits to the local and broader communities. These benefits are far greater than the potential income lost by existing or potential agricultural enterprises. The proposed modification will result in a reduction of remnant ponding from 2.25 hectares pre-mining to 0.73 hectares. The economic benefit because of a reduction in remnant ponding calculated as a precautionary assessment on impacted agricultural resources is $115 per annum.

In summary, the Project will provide considerable economic benefits to the region whilst having negligible impact on agricultural resources, enterprises or related industries.




7 References ABS. (2020, August 26). Retrieved from Australian Bureau of Statistics: www.abs.gov.au

Bureau of Meteorology (BOM). (2020, August 26). Retrieved from www.bom.gov.au

Centennial. (2020). Submissions Report - SSD-5144 Mod 9. Mandalong Mine. Centennial Mandalong Pty Ltd.

DGS. (2018). Centennial Coal Mandalong Pty Ltd Subsidence Predictions & Impact Assessment for LW25-LW31 at the Mandalong Mine. Newcastle: Ditton Geotechnical Services Pty Ltd.

DGS. (2020, August 18). Subsidence Predictions and General Impact Assessment for SSD-5144 Mod 9. Newcastle: Ditton Geotechnical Services Pty Ltd.

GHD. (2019). Centennial Mandalong Mine Water Management Plan December 2019.

GSSE. (2013). Mandalong Southern Extension Project: Soil and Land Capability Assessment. Newcastle: GSS Environmental.

GSSE. (2013). Soil and Land Resource Assessment Mandalong Southern Extension Project. Newcastle: GSSE.

Isbell, R. F. (2002). The Australian Soil Classification Revised Edition . Australia: CSIRO Publishing .

Lake Mac Libraries. (2020, August 26). Mandalong. Retrieved from Lake Mac Libraries: https://history.lakemac.com.au/page-local-history.aspx?pid=1085&vid=20&tmpt=narrative&narid=57

Lake Macquarie City Council. (2014). Lake Macquarie Local Environmental Plan.

Murphy, C. L. (1993). Soil Landscapes of the Gosford - Lake Macquarie Sheet 1:100 000 Sheet . Sydney: Soil Conservation Service of NSW.

NSW DPI. (2006). Beef Stocking Rates and Farm Size - Hunter region 2006. Sydney: NSW Department of Primary Industries.

NSW DPI. (2013). NSW Biosecurity Strategy 2013-2021. Sydney, NSW, Australia.

NSW DPI. (2017). Beef Cattle Gross Margin Budget Coastal Weaners Improved Pasture. Sydney: NSW Department of Primary Industries.

NSW I&I. (2009). Primefact: Measuring Water Salinity. Sydney: NSW Industry and Investment.

NSW OEH. (2012). The Land and Soil Capability Assessment Scheme, Second Approximation. Sydney: NSW Office of Environment and Heritage.

NSW OEH. (2013). Interim Protocol for Site Verification and Mapping of Biophysical Strategic Agricultural Land. NSW Government Office of Environment and Heritage.

SLR. (2017). Soil and Land Resource Assessment Mandalong Transmission Line TL24 Relocation Project. Newcastle: SLR Consulting Australia (Pty) Ltd.




SLR. (2018). Centennial Mandalong Extraction Plan LW25-LW31 Land and Agricultural Resource Assessment. Newcastle: SLR Consulting Australia (Pty) Ltd.

Umwelt. (2020). Flood Impact Assessment. Mandalong Southern Extension Project Modification 9. Newcastle: Umwelt (Australia) Pty Limited.

Water NSW. (2020, August 26). Continuous water monitoring network. Retrieved from Realtimedata Water NSW: https://realtimedata.waternsw.com.au/

630.12518.001

APPENDIX A

Soil Landscape Unit Descriptions

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Mandalong Soil Landscape

The Mandalong Soil Landscape Unit consists of rolling to steep low hills on Patonga Claystone in the Watagan Mountains. The landscape has local relief to 120 metres and slope gradients of between 20 and 60%. The landscape is characterised by narrow crests and ridges, short steep slopes and narrowly spaced drainage lines. The land is regenerating tall open-forest. The soils are dominated by moderately to deep Red, Brown and Yellow Podzolics Soils (Kurosols, Chromosols and Sodosols) on claystone, shallow to moderately deep Yellow Podzolic Soils (Kurosols, Chromosols and Sodosols) on sandstone or rock outcrops along drainage lines.

The limitations of this unit include mass movement hazards, steep slopes, erosion hazards and foundation hazards. Soils have low wet bearing strength, can be acidic, sodic and have low fertility. The land capability is deemed to have generally high to severe limitations to both cropping and grazing.

Watagan Soil Landscape

The Watagan Soil Landscape Unit consists of rolling to very steep hills on fine-grained Narrabeen Group sediments. Local relief is from 50 to 220 metres, with slope gradients more than 25%. The landscape is characterised by narrow convex crests and ridges, steep colluvial side slopes, occasional sandstone boulders and benches. The land is predominantly uncleared tall eucalypt open-forest with closed-forest in sheltered positions. The soils are very complex and include shallow (<50 centimetre) Lithosols/Siliceous Sands and Yellow Earths on coarse sandstones, shallow to deep (<50 to 150 centimetre) Yellow Podzolic Soils and some Red Podzolic Soils on fine-grained bedrock, deep (>150 centimetre) sandstone colluvial deposits of no suitable Group, Yellow Earths, Yellow Podzolic Soils and Siliceous Sands and Alluvial Soils along drainage lines.

Limitations to this unit include mass movement hazard, steep slopes, soil erosion hazard, foundation hazard, occasional rock outcrop and localised seasonal waterlogging. The land capability is deemed to have generally high to severe limitations for cultivation and grazing.

Gorokan Soil Landscape

The Gorokan Soil Landscape Unit consists of undulating low hills and rises on lithic sandstones of the Tuggerah Formation. Local relief is less than 30 metres, with slope gradients less than 15%. The landscape is characterised by broad crests and ridges, long gently inclined slopes and broad drainage lines. The land is partially cleared low open-forest. The soils are dominated by moderately deep Soloths (Sodosols), Yellow Podzolic Soils (Kurosols, Chromosols) on ridges and crests, Yellow and Grey-Brown Podzolic Soils (Kurosols, Chromosols) on slopes and Gleyed Podzolic Soils (Hydrosols) along drainage lines.

Limitations to this unit include very high erosion hazard, foundation hazard (localised), seasonal waterlogging, hardsetting, strongly acidic, low fertility, plastic and impermeable soils. The land capability is deemed to have generally high to severe limitations for regular cultivation, however low limitations for grazing.

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Woodburys Bridge Soil Landscape

The Woodburys Bridge Soil Landscape Unit consists of undulating rises to rolling low hills on Patonga Claystone. Local relief is range from 50 to 80 metres, with slope gradients up to 20%. The landscape is characterised by sandstone capping on crests of steeper hills. The land is predominantly cleared tall open-forest. The soils are dominated by deep (>150 centimetres) Red Podzolic Soils with some Soloths in poorly drained areas on claystone bedrock and shallow to moderately deep (50 to 15 centimetre) Yellow Podzolic Soils on sandstone bedrock.

Limitations to this unit include extreme erosion hazard, high foundation hazard, localised seasonal waterlogging, acid soils of very low fertility, low wet bearing strengths and high erodibility. The land capability is deemed to have generally high to severe limitations for regular cultivation due to the severe erosion hazard and moderate limitations for judicious grazing provided a protective permanent vegetative cover is maintained.

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