Mercury (Hg) contamination on water, sediment and macrozoobenthos in Waelata River, Wamsait Village Waelata Sub-district, Buru District, Maluku Province

Abstract

Gold was found in Buru Island, Maluku Province, Indonesia in November, 2011. Since then, the artisanal small-scale gold mining (ASGM) activity was started in Botak Mount up to now. Mercury was used to extract gold through amalgamation process and produce high volume of wastewater contaminated by Hg to Waelata River, straight to Kayeli Bay. This caused serious problem for the environment. Sampling was done in three locations in Waelata River, Wamsait Village, Waelata Sub-District, Buru District, with the three times of repetition to determine the mercury (Hg) concentration level in the water, sediment and macrozoobenthos. The research result showed that the highest Hg concentration mean in the water, sediment and macrozoobenthos was in ST.02 with the respective values namely 0.0012±0.0001 ppm, 0.0833±0.0062 ppm and 0.0088±0.0003 ppm. On the other hand, the lowest Hg concentration mean was found in ST.01 with the respective values namely < 0.0005±0.0000 ppm, 0.0228±0.0019 ppm and 0.0050±0.0034 ppm. The wastewater was produced by the gold mining activities that did not flow to ST.01, so that Hg in the wastewater did not have any correlation with the Hg in sediment and macrozoobenthos (p<0.05), however it flowed from ST.02 to ST.03 so that the Hg in the water has correlation with Hg in sediment and macrozoobenthos (p>0.05).