The 2006 western Java tsunami deposited a discontinuous sheet of sand up to 20 cm thick, flooded coastal southern Java to a depth of at least 8 m and inundated up to 1 km inland. In most places the primarily heavy mineral sand sheet is normally graded, and in some it contains complex internal stratigraphy. Structures within the sand sheet probably record the passage of up to two individual waves, a point noted in eyewitness accounts. We studied the 2006 tsunami deposits in detail along a flow parallel transect about 750 m long, 15 km east of Cilacap. The tsunami deposit first becomes discernable from the underlying sediment 70 m from the shoreline. From 75 to 300 m inland the deposit has been laid down in rice paddies, and maintains a thickness of 10-20 cm. Landward of 300 m the deposit thins dramatically, reaching 1 mm by 450 m inland. From 450 m to the edge of deposition (around 700 m inland) the deposit remains \1 mm thick. Deposition generally attended inundation-along the transect, the tsunami deposited sand to within about 40 m of the inundation limit. The thicker part of the deposit contains primarily sand indistinguishable from that found on the beach 3 weeks after the event, but after about 450 m (and roughly coinciding with the decrease in thickness) the tsunami sediment shifts to become more like the underlying paddy soil than the beach sand. Grain sizes within the deposit tend to fine upward and landward, although overall upward fining takes place in two discrete pulses, with an initial section of inverse grading followed by a section of normal grading. The two inversely graded sections are also density graded, with denser grains at the base, and less dense grains at the top. The two normally graded sections show no trends in density. The inversely graded sections show high density sediment to the base and become less dense upward and represents traction carpet flows at the base of the tsunami. These are suggestive of high shear rates in the flow. Because of the grain sorting in the traction carpet, the landward-fining trends usually seen in tsunami deposits are masked, although lateral changes of mean sediment grain size along the transect do show overall landward fining, with more variation as the deposit tapers off. The deposit is also thicker in the more seaward portions than would be produced by tsunamis lacking traction carpets.

Ore processing industry in Indonesia applies the international standard of environmental management system based on ISO 14001:2015. The implementation of clause 6.1.2 requires every organization to identify the environmental aspects of its operations, as an initial step in environmental management. The objective of this research is to develop a structured approach in identifying the environmental aspects and impacts so that an evaluation on the risks, opportunities as well as severity of possible environmental impacts can be conducted. The employed methods involve life-cycle approach and risk assessment method with four-cell risk assessment matrix in environmental risk determination. The results of this risk assessment can give an overview of environmental aspects and impacts, so that control priority can be determined in order to reduce the risks.

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Monitoring workers’ exposure to occupational noise is essential, especially in industrial areas, to protect their health. Therefore, it is necessary to collect information on noise emitted by machines in industries. This research aims to map the noise from mechanized mineral ore industry using the kriging interpolation method, and ArcGIS 10.5.1 to spatially process and analyze data. The experimental calculation result of the semivariogram showed a 0.83 range value, with an essential parameter of 1.75 sill and a spherical total theoretical model. The result shows that the main machines with the highest power consumption and the Leq value are located in the southwest position of the sampled areas with a noise map-projected to assess the workers’ noise exposure level. In conclusion, the study found that the highest noise level was generated ranged from 88 to 97 dBA and contributed to the whole sound pressure level at certain positions.