Performance monitoring of the wastewater system of Bharati Station, Antarctica

The untouched condition of Antarctica's environment is a result of its inherent absence of human activity. Nevertheless, with the introduction of scientific research stations and human presence, a considerable volume of wastewater has been produced by these research facilities. The wastewater needs to be treated before discharge and has strict rules and regulations set by the Antarctic Treaty (Annexure III). However, the performance of the wastewater treatment plant and the data on the quality of the effluents being discharged into the sea by different stations are limited. In this study, the performance of the wastewater treatment plant at Bharati research station located at Larsemann Hills, East Antarctica was investigated from 2015 to 2022. Physical and chemical parameters such as pH, EC, NH₄–N and COD were determined in effluents from the drinking water plant, blackwater and greywater plant from Bharati station. The pH and EC of the effluents were measured using portable probes, ammonia was measured spectrophotometrically, and COD was measured using the closed reflux digestion method. The monthly data of the effluents from 2015 to 2022 for pH, EC, NH₄–N and COD indicate values within the permissible limits except for a few parameters at a certain time frame. It was observed that the pH of black, grey and drinking water varied between pH 6.5 and 9.1. Both grey and blackwater showed a decreasing conductivity trend, suggesting decreased ionic content. The blackwater exhibited an increase in ammonia concentration and COD trend, indicating higher organic pollution levels, while the grey water displayed a decreasing trend in COD, indicating a reduction in organic matter content. The study also investigated the correlation between NH₄–N concentration in wastewater and greywater with levels of COD and compared these levels with standard values to assess effluent water quality. The data will provide baseline values to assess any malfunctioning of the wastewater system in treating the contaminants. Effluent data from other Antarctic stations show a high value compared with the effluents from Bharati station. Such variability largely depends on the station size, water usage and number of expedition members during the summer and winter seasons.