Academic literature on the topic 'Water Pollution Northern Territory Alligator Rivers Region'

Estuaries are recognised globally as areas of high production, diversity and high economic value. Exploitation of the economic potential of estuaries and attendant infrastructural development plus expansion of human populations has resulted in degradation of estuaries worldwide. Many estuaries of northern Australia, in contrast, remain in good ecological condition. The estuarine fish fauna of the South Alligator River, Kakadu region of northern Australia was investigated to determine seasonal and spatial variation in composition. Beam trawls were used at 94 locations over the wet and dry seasons of 2012. In total, 81 taxa were collected, 26 of which had not previously been recorded in the river. Sciaenidae and Engraulidae dominated species richness and abundance. Samples were heterogeneous in terms of composition and abundance in a manner unrelated to any measured aspect of the habitat over which trawls occurred. Species richness was higher in the lower estuary than the upper estuary and more species were detected during the wet season. Turnover in assemblage structure between sampling occasions was associated with seasonal variation in discharge concordant with changes in salinity and potentially productivity. Compositional variation was largely ascribed to differential spawning phenology of adults and tolerance to fluctuating salinity. The Kakadu region supports a rich fish fauna moderately distinct from that observed elsewhere in the Northern Territory. Pronounced temporal turnover in assemblage structure and spatial variation at a variety of scales (i.e. within samples, and within and between rivers) collectively pose a challenge to management in light of ongoing and proposed development of the water resources of northern Australia, including its estuaries.

The Nabarlek uranium mine is located in the Alligator Rivers Region of the Northern Territory of Australia. The site lies in the wet/dry topics with an annual rainfall of about 1400mm, which falls between October and April. The site operated as a “no release” mine and mill between 1979 and 1988 after which time the facility was mothballed until decommissioning was required by the Supervising Authorities in 1994. The dismantling of the mill and rehabilitation earthworks were completed in time for the onset of the 1995–96 wet season. During the operational phase accumulation of excess water resulted in irrigation of waste water being allowed in areas of natural forest bushland. The practice resulted in adverse impacts being observed, including a high level of tree deaths in the forest and degradation of water quality in both ground and surface waters in the vicinity. A comprehensive environmental monitoring programme was in place throughout the operating and rehabilitation phases of the mine’s life, which continues, albeit at a reduced level. Revegetation of the site, including the former irrigation areas, is being observed to ascertain if the site can be handed back to the Aboriginal Traditional Owners. A comprehensive review of proximal water sampling points was undertaken in 2001 and the data used to provide a snapshot of water quality to assist with modelling the long term prognosis for the water resources in the area. While exhibiting detectable effects of mining activities, water in most of the monitoring bores now meets Australian drinking water guideline levels. The paper reviews the history of the site and examines the accumulated data on water quality for the site to show how the situation is changing with time. The paper also presents an assessment of the long term future of the site in respect of water quality.