Norfolk Island acid sulfate soils (ASS) 2024

Brief description

This dataset depicts polygons of acid sulfate soils (ASS) identified as part of the Norfolk Island Water Resource Assessment 2019 - 2020 (NIWRA) and additional targeted work in 2020 - 2023. Areas were mapped due to the importance to water quality of fresh and marine water, groundwater recharge, surface water storage, managed aquifer recharge and impact on infrastructure specifically in the World Heritage listed Kingston and Arthur’s Vale Historic Area (KAVHA). The full extent of ASS has not been identified on NI primarily concentrating to date on areas that support the NIWRA and water quality management in the Kingston area. Acid sulfate soils is the name given to naturally occurring soils, unconsolidated sediments or organic accumulations (peat) in which sulfuric acid will be produced, is being produced, or has been produced in amounts that have a lasting adverse impact to soil, water, infrastructure and the environment. Further acid sulfate soil information can be found in the (a) NIWRA technical report (Petheram et al., 2020) and described in Appendix D of the NIWRA technical report, (b) Norfolk Island Water Resource Assessment: Acid sulfate soils (Fitzpatrick et al., 2023), (c) Acid sulfate soil management in the Kingston and Arthur's Vale historic area (KAVHA) on Norfolk Island (Fitzpatrick et al., 2023) and (d) Management of excavated peaty acid sulfate soil with hypersulfidic material from a potential new Headstone dam on Norfolk Island (Fitzpatrick et al., 2020). This data is an update to the previously released acid sulfate soils of Norfolk Island.
Lineage: The acid sulfate soil dataset has been generated from a range of inputs and processing steps. The following is an overview of the methods detailed in Petheram et al. 2020 and Fitzpatrick et al. 2023. 1. Collated existing data (relating to: soils, climate, topography, natural resources, remotely sensed, of various formats: reports, spatial vector, spatial raster). 2. Selection of soil and land attribute site data locations. 3. Fieldwork was carried out to collect new attribute data, soil samples for analysis and build an understanding of geomorphology and landscape processes. 4. Esri ArcMap was used to delineate polygons. Associated datasets used included LiDar, DEM derivatives (TWI, slope), satellite imagery and historical aerial photography. 5. QA Quality assessment of the data was conducted by on-ground expert (qualitative) examination of the mapping.