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Ship-generated greywater contains a variety of pollutants which, through various pathways, usually are discharged into the sea. To understand the seasonal variation in greywater volumes, the contaminant concentrations in, and the potential hazard of, ship-generated greywater streams, a four-phase strategy for sampling, characterization and hazard assessment of greywater was developed and implemented. Eight greywater streams, sampled from five ships, were characterized for selected pollutants. The metals Zn, Cu, Mn and the metalloid, As, collectively contributed 98 % to the Hazard Index. Laundry greywater had the highest average concentration of phosphorus (42 mg/l) while galley greywater had the highest average concentration of nitrogen (30 mg/l). The geometric means of COD-Cr, BOD 5 , TSS and P exceeded the IMO resolution MEPC 227(64) guideline values for sewage effluent from Advanced Wastewater Treatment Plants. The results establish the basis for and contribute to discussions on, the optimization of ship-generated greywater management and the establishment of potential regulatory strategies in the Baltic Region. Discharge routes for greywater and pollutants from ships into the Baltic Sea. [Display omitted] • Zn, Cu, Mn and As drive the hazard potential of greywater and contribute 98% to the Hazard Index (HI). • Average MC of nitrogen is highest in galley greywater while the average MC of phosphorus is highest in laundry greywater. • The geomean of COD-Cr, BOD 5 , TSS and P surpass Resolution MEPC 227 (64) guideline values for sewage effluent from AWTPs. • No significant differences exist in HIs between GW, BW, mixed GW/BW from ships, and domestic wastewater. [ABSTRACT FROM AUTHOR]

The necessity of having a process in place for adequate risk assessment of shipwrecks that pose a threat to the marine environment is today internationally acknowledged. However, retrieving the desired data for such a risk assessment can prove challenging. One means of addressing this problem is to make use of experts' knowledge and experience. The purpose of this paper is therefore to present and analyse data for risk assessment of shipwrecks derived by expert elicitation. The main outcome is the experts' estimations of (i) the generic probability of an opening in a shipwreck due to the occurrence of a number of activities and (ii) estimations of the degree to which site-specific and wreck-specific indicators affect the probability of opening. Results show that the derived information is applicable in probabilistic shipwreck risk assessment and that the VRAKA framework now contains needed information for integrating generic and site-specific information using Bayesian updating. [ABSTRACT FROM AUTHOR]

Shipwrecks on the sea floor around the world may contain hazardous substances that can cause harm to the marine environment. Today there are no comprehensive methods for environmental risk assessment of shipwrecks, and thus there is poor support for decision-making on prioritization of mitigation measures. The purpose of this study was to develop a tool for quantitative risk estimation of potentially polluting shipwrecks, and in particular an estimation of the annual probability of hazardous substance discharge. The assessment of the probability of discharge is performed using fault tree analysis, facilitating quantification of the probability with respect to a set of identified hazardous events. This approach enables a structured assessment providing transparent uncertainty and sensitivity analyses. The model facilitates quantification of risk, quantification of the uncertainties in the risk calculation and identification of parameters to be investigated further in order to obtain a more reliable risk calculation. [ABSTRACT FROM AUTHOR]