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ENVIRONMENTAL IMPACT STATEMENT GLOUCESTER RESOURCES LIMITED Section 4 – Environmental Features, Management Amended Rocky Hill Coal Project Measures and Impacts Report No. 806/13 4.8 SOILS AND LAND AND SOIL CAPABILITY The soils assessment of the amended Project was undertaken in two parts. The assessment of soils within the Mine Area and power line corridors was completed by Geoff Cunningham Natural Resource Consultants Pty Ltd as part of the 2013 Project assessment whilst the assessment of soils within the private haul road corridor was completed by Soil Management Designs as part of the amended Project. The full assessments are presented in Volume 4 Parts 10A and 10B of the Specialist Consultant Studies Compendium and are referenced throughout this section as GCNRC (2013a) and SOILmgt (2016), with a summary of the assessments presented in the following subsections. Relevant soils information is also discussed in Section 4.17 with respect to agricultural resources within the Site. 4.8.1 Introduction Based on the risk assessment undertaken for the amended Project (Section 3.3.1 and Appendix 6), the potential impacts relating to soils and their risk rankings after the adoption of standard mitigation measures are as follows. Inadequate soils available for rehabilitation purposes leading to less successful rehabilitation and increased rehabilitation costs and maintenance to the Mine Area and private haul road corridor (low). Degradation of soil in stockpiles leading to less successful rehabilitation and increased rehabilitation costs and maintenance (low). Erosion of soil stockpiles within the Waukivory Creek / Oaky Creek catchment areas leading to increased sediment loads in both creeks (low). In addition, the Director-General’s Requirements issued by the then DP&I (now DPE) identified “Soil, Land Capability, and Agricultural Suitability” as key issues requiring assessment. The principal assessment matters relating to soils and agriculture include the following. Soils and land capability (including salinisation and contamination). Pre-mining and post-mining agricultural assessment and mapping (including Land Capability and Agricultural Suitability mapping) of soil characteristics across all proposed disturbance areas, and an assessment of their value and rehabilitation limitations. A detailed description of the measures that would be implemented to avoid, reduce or mitigate impacts of the development on local agricultural resources and/or enterprises. It is noted that since the DGRs were issued and the release of the Upper Hunter Strategic Rural Land Use Plans, the former “Land Capability and Agricultural Suitability” mapping has been superseded by “Land and Soil Capability” mapping of NSW (OEH) which includes the former Gloucester LGA. R. W. CORKERY & CO. PTY. LIMITED 4-219 GLOUCESTER RESOURCES LIMITED ENVIRONMENTAL IMPACT STATEMENT Amended Rocky Hill Coal Project Section 4 – Environmental Features, Management Report No. 806/13 Measures and Impacts Additional matters for consideration in preparing the EIS were also provided in the correspondence attached to the DGRs from the EPA, the former Gloucester Shire Council, DRE and Hunter-Central Rivers NSW Catchment Management Authority. The matters identified are generally consistent with the DGRs. The soils assessment outlined in this section focusses upon the physical and chemical attributes of the soil resources within the Site, particularly with respect to their stripping, stockpiling, management and re-use. GCNRC (2013b), i.e. Appendix 1 of the Agricultural Impact Statement Volume 5, Part 13 of the Specialist Consultant Studies Compendium, presents an additional assessment of the agricultural characteristics of the soils within the Mine Area. This additional assessment was assembled given the Applicant’s objective is to return all areas of disturbance in the Mine Area to the same land capability that existed prior to mining, with a mixture of grazing and passive native conservation uses. 4.8.2 Soils Occurrences 4.8.2.1 Local Setting A review of published literature was conducted by GCNRC (2013a) and SOILmgt (2016) to identify the soil types present within the Site. The Site is located within an area covered by the Dungog 1:100 000 scale Soil Landscapes Map – Figure 4.52 (Henderson 2000a), with the following six soil landscape units defined within Henderson (2000b) identified as present within and in the vicinity of the Site. Gloucester (go) Soil Landscape; Gloucester River (gu) Soil Landscape; Gloucester Bucketts (gb) Soil Landscape; Wards River (wr) Soil Landscape; Stroud Road (sr) Soil Landscape; and Craven (cn) Soil Landscape (variant a). The Gloucester (go) Soil Landscape comprises undulating low hills on sedimentary rocks with rocky outcrops generally absent, and is the most common soil landscape across the Mine Area. The soils of this soil landscape are classified as Sodosols, Kurosols and Tenosols within the Australian Soils Classification. The Wards River (wr) Soil Landscape comprises low rolling hills on sediments of the Gloucester Coal Measures. The Wards River Soil Landscape is the second most common soil landscape within the Mine Area and is the principal soil landscape within the private haul road corridor. The soils of this landscape are classified as Kurosols and Tenosols within the Australian Soils Classification. 4-220 R. W. CORKERY & CO. PTY. LIMITED ENVIRONMENTAL IMPACT STATEMENT GLOUCESTER RESOURCES LIMITED Section 4 – Environmental Features, Management Amended Rocky Hill Coal Project Measures and Impacts Report No. 806/13 Figure 4.52 Local Soil Landscapes A4/Colour Figure dated 27/7/16 inserted on 29/7/16 R. W. CORKERY & CO. PTY. LIMITED 4-221 GLOUCESTER RESOURCES LIMITED ENVIRONMENTAL IMPACT STATEMENT Amended Rocky Hill Coal Project Section 4 – Environmental Features, Management Report No. 806/13 Measures and Impacts The Gloucester River (gu) Soil Landscape occurs in the western part of the Mine Area and across the northern part of the private haul road corridor and occupies broad level alluvial plains with occasional small swamps and swampy oxbows associated with the Avon River and Waukivory Creek. These soils are classified as Chromosols and Hydrosols within the Australian Soils Classification. The Stroud Road (sr) Soil Landscape is present in the eastern section of the Mine Area and is characterised by rolling and undulating hills on volcanics. Landforms include moderately broad crests with some rock outcrop, convex upper slopes, lower ridges and moderately broad drainage plains. Within the Australian Soils Classification, the soils of the crests, outcrops and upper slopes are classified as Tenosols and Dermosols, whilst those of the lower ridges are classified as Ferrosols and those of the drainage plains are classified as Vertosols. The Gloucester Buckets (gb) Soil Landscape comprises rolling to very steep hills on volcanics and sediments and occurs in the far eastern section of the Mine Area, generally beyond the proposed limit of disturbance. Relief varies between 60m and 350m with slopes typically 25% to >50%. Terracetting and hummocky terrain are present along with small (30m-50m) scarps. Rock outcrop and surface boulders are common. The soils are classified as Rudosols and Tenosols within the Australian Soil Classification. The Craven (cn) Soil Landscape (variant a) occurs within low and wide drainage depressions with deep eroded watercourses and long swamps. These soil landscapes occur in areas associated with major watercourses and are located within the southern sections of the Mine Area and private haul road. The soils are classified as Kurosols within the Australian Soil Classification. 4.8.2.2 Site Soils In order to provide a level of detail in the soils mapping which would be more appropriate for the effective management of the soils resources within the Site, detailed investigations were undertaken including a desktop assessment, test pitting, profile description and physical and chemical analyses. Prior to field investigations, the Site was subjected to air photo interpretation to ascertain the nature of the landforms present and to develop a broad appreciation of the landform units that would require sampling. Field sampling involved test pitting using a backhoe and the complete description of 40 profiles within the Mine Area to a maximum depth of 2.5m below ground level and a further 10 profiles within the private haul road corridor to a maximum depth of 1.4m below ground level. The location of each soil sampling site is shown in Figure 4.53. The soil profiles at each test pit location were fully examined with the following soil properties noted. Texture Gravel/stone occurrence Fabric Presence of roots Structure Presence of lime Consistence Presence of manganese Colour pH 4-222 R. W. CORKERY & CO. PTY. LIMITED ENVIRONMENTAL IMPACT STATEMENT GLOUCESTER RESOURCES LIMITED Section 4 – Environmental Features, Management Amended Rocky Hill Coal Project Measures and Impacts Report No. 806/13 Figure 4.53 Soil Mapping Units (A4 Colour) Figure dated 27/7/16 inserted on 29/7/16 R. W. CORKERY & CO. PTY. LIMITED 4-223 GLOUCESTER RESOURCES LIMITED ENVIRONMENTAL IMPACT STATEMENT Amended Rocky Hill Coal Project Section 4 – Environmental Features, Management Report No. 806/13 Measures and Impacts Chemical analyses of the defined layers within the 40 pits within the Mine Area and seven representative pits within the private haul road corridor were conducted either in the field (pH) or at NATA accredited soil testing laboratories