A NHT (National Heritage Trust) funded project headed by the NRM Cradle Coast to delineate marine subaqueous and intertidal areas with potential to contain Acid Sulfate Soils (ASS). The dataset forms part of the larger project pertaining to ‘Tasmanian Acid Sulfate Soils Information’ (TASSI) with the aim of providing better awareness to stake holders and planners in regards to the distribution of Acid Sulfate Soils in marine subaqueous and intertidal environments of Tasmania. Marine subaqueous and intertidal environment for the sake of the TASSI project was defined as the seaward zone below the high water (tidal) mark and extending into the sub-tidal zone. The dataset comprises polygons mapped at the 1:25,000 scale and geo-referenced to the GDA94 datum. Each polygon is attributed with a descriptor/code that describes the ASS landscape that a polygon represents as well as the probability of the occurrence of ASS. The descriptor/code pertains to the Atlas of Australian Acid Sulfate Soils (developed in part by CSIRO and used on the ASRIS website, http://www.asris.csiro.au ). Ancillary dataset information that were used to model and derive the subsequent codes are embedded within the dataset attribute table.