While provision of safe drinking water is considered a basic human right, there are major challenges in the developing world for its provision. The ability to deliver safe water using a cost-appropriate technology is a major aspect of the problem. One of the technologies that has the potential to contribute significantly is the ceramic water filter (CWF); however, as shown herein, there are significant differences between performance of CWFs in the laboratory and in field applications. The CWFs employed in this study (field and laboratory) have a pore fraction of 21.0 -22.4% and an average maximum pore diameter of 5.7 -15.2 μm. Field studies were completed in Longhai City, China, a rural community in southeastern China with red earth, high precipitation and intensive human/ domestic activities. During field trials, CWFs demonstrated an average removal efficiency of 94.7%, with values ranging from 75 -100%, whereas in laboratory studies, average removal efficiency was determined to be 99.5%, with values ranging from 97.7 -99.9%. Differences between the lab and field removal efficiencies are attributed to contamination of the filter element and receptacle by villagers during field utilization and cleaning. Effective technology transfer to the end-user is required to achieve the bacterial removal efficiency attainable by the technology itself.

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An integrated simulation-assessment approach (ISAA) was developed in this study to systematically tackle multiple uncertainties associated with hydrocarbon contaminant transport in subsurface and assessment of carcinogenic health risk. The fuzzy vertex analysis technique and the Latin hypercube sampling (LHS) based stochastic simulation approach were combined into a fuzzy-Latin hypercube sampling (FLHS) simulation model and was used for predicting contaminant transport in subsurface under coupled fuzzy and stochastic uncertainties. The fuzzy-rule-based risk assessment (FRRA) was used for interpreting the general risk level through fuzzy inference to deal with the possibilistic uncertainties associated with both FLHS simulations and health-risk criteria. A study case involving health risk assessment for a benzene-contaminated site was examined. The study results demonstrated the proposed ISAA was useful for evaluating risks within a system containing complicated uncertainties and interactions and providing supports for identifying cost-effective site management strategies.

In this study, an inexact two-stage stochastic partial programming (ITSPP) method is developed for tackling uncertainties presented as intervals and partial probability distributions. A scenario-based interactive algorithm is proposed to solve the ITSPP model. This algorithm is implemented through: (i) obtaining extreme points of the linear partial information (LPI); (ii) generating an inexact two-stage stochastic programming (ITSP) model under each extreme point; (iii) solving ITSP models through interactive algorithm proposed by Huang and Loucks (Civil Eng Environ Syst 17: 2000); (iv) acquiring the interval solutions under each extreme point and the final optimal interval for the objective function. The developed method is applied to a case study for waterresources planning. The modelling results can generate a series of decision alternatives under various system conditions, and thus help decision makers identify the desired water-resources management policies under uncertainty.

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