The USEPA (2001) water quality nutrient criteria will have a significant impact on water pollution control industry due to stringent N and P requirements. This paper presents an update of findings on successful total N (TN) and total P (TP) technologies being implemented at existing wastewater treatment plants (WWTP) to achieve low TN and TP effluents and some key challenges in achieving lower levels. Plants consistently achieving <5 mg TN/L and < 0.5 mg TP/L were identified from a worldwide literature search and plant data collection. Technology gaps and research needs to improve successful technologies to achieve very low TN and TP effluents are summarised in this paper. The dissolved and colloidal organic N have been identified as major challenges in achieving very low levels of TN. Technical and economic challenges to achieve very low TP effluents include alkalinity deficiency, high chemical usage, high sludge production and lack of sufficient influent BOD for biological P uptake.

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In Part I of this two‐part paper, the characteristics of mine disasters and their effects are presented with case studies from coal, metal and non‐metal mines leading to an amplification of their causes and opportunities for control. The disasters discussed encompass those which threaten the health and the safety of miners and those which affect the general population. In Part 2 of the paper, which will be published in the November 1995 issue ofNatural Resources Forum, the approaches to hazard and disaster control are reviewed with particular attention to laws and regulations to promote health and safety at the workplace, and general welfare in mining communities. Further, a systems approach to disaster control is outlined.

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