S. Dallas

A monitoring of environmental effects from household greywater reuse for garden irrigation.

The option of reusing greywater is proving to be increasingly attractive to address the water shortage issue in many arid and semiarid countries. Greywater represents a constant resource, since an approximately constant amount of greywater is generated from kitchen, laundries, bathroom in every household daily, independent of the weather. However, the use of greywater for irrigation in particular for household gardening may pose major hazards that have not been studied thoroughly. In this study, a 1-year monitoring was conducted in four selected households in Perth, Western Australia. The aim of the monitoring works is to investigate the variability in the greywater flow and quality, and to understand its impact in the surrounding environments. Case studies were selected based on different family structure including number, ages of the occupants, and greywater system they used. Samples of greywater effluent (showers, laundries, bathtub, and sinks), leachate, soil, and plants at each case study were collected between October 2008 and December 2009 which covered the high (spring/summer) and low (autumn/winter) production of greywater. Physical and chemical tests were based on the literature and expected components of laundry and bathroom greywater particularly on greywater components likely to have detrimental impacts on soils, plants, and other water bodies. Monitoring results showed the greywater quality values for BOD, TSS, and pH which sometimes fell outside the range as stipulated in the guidelines. The soil analyses results showed that salinity, SAR, and the organic content of the soil increased as a function of time and affected the plant growth. Nutrient leaching or losses from soil irrigated with greywater shows the movement of nutrients and the sole impact from greywater in uncontrolled plots in case studies is difficult to predicted due to the influence of land dynamics and activities. Investigative and research monitoring was used to understand greywater irrigation in households. Greywater quality is very site specific and difficult to predetermine or control except for the use of some recommended household products when using greywater. Investigative and research monitoring was indicated that greywater quality is very site specific and difficult to predetermine or control except for the use of some recommended household products when using greywater.

Heavy metals in a constructed wetland treating industrial wastewater: distribution in the sediment and rhizome tissue

This study assessed copper and zinc distribution in the surface layer of sediment and rhizome tissue within the saturated surface vertical flow constructed wetland of CSBP Ltd, a fertiliser and chemical manufacturer located in Western Australia. Sediment and Schoenoplectus validus rhizome samples were collected at various distances from the inlet pipe while water samples are routinely collected. Water samples were analysed for nutrients and metals, sediments were analysed for total and bioavailable metals and rhizomes were analysed for total metals only. Mean influent copper and zinc concentrations were 0.19 mg/L and 0.24 mg/L respectively. The distribution of bioavailable Cu and Zn in the top sediment layer follows a horizontal profile. Analysis of variance (ANOVA) showed that the bioavailable fraction of these metals in sediments near the inlet pipe (30.2 mg/kg Cu and 60.4 mg/kg Zn) is significantly higher than in sediments at the farthest location (10.3 mg/kg Cu and 26.1 mg/kg Zn). The average total Cu concentration in the sediment at the 2 m location has reached the 65 mg/kg trigger value suggested by the Interim Sediment Quality Guidelines (ANZEEC 2000). Cu and Zn concentrations in the rhizome of S. validus do not vary significantly among different locations. Whether Cu and Zn concentrations at the CSBP wetland may reach toxic levels to plants and bacteria is still unknown and further research is required to address this issue. The surface component of the wetland favours sedimentation and binding of metals to the organic matter on the top of the sediment, furthermore, the sediment which tends to be anoxic with reducing conditions acts as a sink for metals.

Renewable energy in the context of environmentally sound technologies — training and research programmes at the Environmental Technology Centre, Murdoch University

The Murdoch University Environmental Technology Centre is an operational site where renewable energy systems are integrated into the overall functioning of the Centre within the broader context of environmentally sound technologies (ESTs). Research and training programmes in renewable energies, energy efficiency strategies and energy conservation, and how they integrate with ESTs have been developed. They have been applied through a range of low-cost short courses, undergraduate teaching, industry training initiatives, international and institutional programmes.

A solar-powered village water supply system from brackish water

Publisher Summary This chapter presents the findings from field situations, discusses the proposed central lands installation, and describes the areas where further research is indicated. Most of remote Aboriginal communities rely on groundwater for their potable water supplies. However, this source is often highly mineralized in excess of the recommended drinking water quality guidelines for long-term human consumption. The self-contained, solar powered water supply system provides 400 liters/day of high quality, desalinated drinking water. A system, capable of meeting the requirements of larger communities of up to 150 people, providing 1500 liter/day is currently in the prototype stage and undergoing performance monitoring before entering commercial production.

Evaluation of a bacterial algal control agent in tank-based experiments.

A bacterial-based bioremediation product, LakeRelief™ by Novozymes (Waterguru LakeRelief, 2011), was tested in a series of experiments between October 2008 and March 2009 to evaluate its suitability as a short-term intervention technique to reduce algal blooms in the Swan-Canning River system. Results from fibreglass tank experiments (1100 L) suggested that the product did not actively attack and lyse algal cells. The product decreased NH(4) and NO(x) concentrations in treated tanks, both aerated and non-aerated. Product application decreased PO(4) concentrations in non-aerated tanks but not in aerated tanks. The product appeared to suppress algal growth in non-aerated tanks over short periods (several days). Algal growth regularly diminished after product application but reappeared shortly afterwards. Aeration had a negative effect on bacterial proliferation in the tanks, possibly through alteration of environmental conditions (e.g. water mixing). As a consequence of the environmental conditions in the tanks being counterproductive to the development of a representative microbial composition, several aspects regarding the products effectiveness could not be assessed satisfactorily in the tank experiments. The importance of long-term nutrient immobilisation into a well developed food web and the subsequent nutrient removal through removal of the top order organisms is highlighted.

PRETREATMENT INVESTIGATIONS AND FIELD TRIALING OF AN INNOVATIVE SOLAR-POWERED REVERSE OSMOSIS DESALINATION UNIT

The Remote Area Developments Group (RADG) at Murdoch University in collaboration with a local manufacturer, Venco Products Pty Ltd have developed a solar-powered reverse osmosis desalination unit (‘Solarflow’) specifically designed for remote areas. The unit has recently been commercialised with eighteen units presently in operation through Australia and South East Asia. Several sites where units have been requested however, notably Central Australia and Indonesia, have feed water which is marginal in terms of its ability to be treated by reverse osmosis without some form of pretreatment. Guidelines for feed water pretreatment generally apply to large scale commercial units which operate at high recovery ratios and thus have limited applicability to the Solarflow unit. Research at Murdoch Universitys Environmental Technology Centre (ETC) is currently underway to determine the performance of the units both under laboratory and field conditions over the longer term with marginal feed waters. This will allow an assessment of maintenance requirements, membrane life expectancy and the design of appropriate pretreatment systems to enable the units to perform reliably in remote areas. This paper will describe the findings to date and the areas where further research is indicated..

A Potential Reuse of Greywater in Developed and Developing Countries

The interest in greywater reuse as an alternative water supply is increasing in most part of the World. In Perth, Western Australia (WA), an industrial association to promote greywater reuse named Grey Water Industry Group (GWIG) has been established. Malaysia is a country seemingly endowed with abundant water resources with an annual average rainfall of more than 2000 mm. Despite its high rainfall and water resources compared to other regions in the world, Malaysia still suffers water problems (both excesses and deficits). The present work describes the suitability of greywater reuse in water supply strategy and wastewater management in Malaysia in comparison to that applied in Australia. Greywater should not be seen as a waste product, but as a valuable resource in wastewater management. Based on the comparison study between Australia and Malaysia, it appeared that the adoption of greywater treatment in Malaysia is more feasible and meaningful than the reuse approach, which creates problems in some instances when the greywater system is inappropriately designed for the type of environment. However, proper legislation, awareness and environmental considerations in terms of geochemistry characteristics, selection of the treatment method and the need for a paradigm shift are essential keys to ensuring optimum utilization of greywater as a future water resource in Malaysia.

An assessment of Kalgoorlie Consolidated Gold Mines and Boddington Gold Mine water sources and proposed water auditing framework underpinning improved water allocation compliance and reporting

Abstract Water auditing and water conservation measures are fast becoming the quantitative tools for water balance reporting in the mining and minerals processing sector. Therefore, this paper was written to describe the process of water auditing in a goldmining environment and to contribute towards building an appropriate water management framework for The Cooperative Research Centre (CRC) for sustainable resource processing (CSRP). The research will assist with the assessment of water balances in mining and hydrometallurgical processes and ongoing probabilistic modelling for Newmont Mining Corporation, its wholly owned gold mines, and its joint venture operation of Kalgoorlie Consolidated Gold Mines (KCGM). Kalgold or KCGM are the managers of a joint venture project between Barrick Australia (50 per cent) and Newmont Mining Corporation (50 per cent) at Kalgoorlie, Western Australia (WA). Boddington Gold Mine (BGM), Western Australia, will commence operations this year and manage the new goldmine expansion project. BGM is 100 per cent Newmont owned and will operate to continue mining gold and copper from the existing (BGM) site that was decommissioned in 2001.