A thesis submitted in partial fulfillment of the requirement for t he degree of Master of Science, School of Environment, Resources & Development

Thesis (M.Sc.) - Asian Institute of Technology, 1994

The study was carried out to determine the potential water pollution caused by Bien Hoa Industrial Estate in south Vietnam, to suggest an integrated water pollution control management approach for the whole estate. Two alternatives for an integrated water pollution control management approach for BHIE were proposed . As the first alternative, a central treatment plant (CTP) was proposed to treat both industrial and domestic wastewater biologically . However, presence of toxic, harmful substances, and/ or high concentrations of organic substances and suspended solids in certain industrial wastewater require pretreatment and segregation of waste. As the second alternativ e, an addition of a combined treatment plant to the CTP was recommended to remov e and recover h eavy metals. There are three po ssible bio~ogical treatment methods for the CTP . They are aquatic weed system, waste stabilization pond, and activated sludge. Since the limited availability of land, the activated sludge system was suggested for the CTP . Preliminary design shows that : conventional activated sludge requires about 2 ha of land and 42252 m3 of tank volume; extended aeration requires about 3 ha of land and 61954 m3 of tank v olume. Preliminary cost estimate for the activated sludge system shows that treatment cost for 1 m3 of wastewater is about $ 0.15 U.S. Priorities in most polluting industries were determined among 49 factories/ enterprises in BHIE . Dong Nai Paper Company (paper-match-wood industry) and Dong Nai Storage Battery Enterprise (chemical industry) were identified as the most polluting industries. An in depth study was carried out to identify the major sources and characteristics of wastewater . generated from these industries, and to suggest immediate specific pollution control measures for these industries. These measures are needed to reduce the pollution load before the integrated water pollution control management approach, including the CTP, for BHIE to be implemented . These two case studies are seen as an exemplary approach to determine water pollution control measures for the other priority industries for short term implementation . Pretreatment requirement for the remaining industries in BHIE are also mentioned in this study .