ENVR 890-2 – GLOBAL WATER SANITATION AND HYGIENE - TAKE-HOME FINALName (Print)______________________. Honor Pledge (Sign)___________________________This take-home final exam must be turned in by April 29, 2009YOU MAY USE PUBLISHED OR INTERNET ACCESSIBLE LITERATURE, INCLUDINGBOOKS, JOURNAL ARTICLES, REPORTS AND THE LIKE. HOWEVER, EACH OF YOUARE EXPECTED TO WORK INDEPENDENTLY AND WITHOUT CONSULTATION WITHOTHERS IN CONCEPTUALIZING, FORMULATING AND PREPARING YOUR ANSWERS.PLEASE MAKE YOUR ANSWERS NO LONGER THAN 5 TYPE-WRITTEN,DOUBLE-SPACE PAGES PER QUESTION.YOU MUST ANSWER ANY THREE (3) OF THE FOLLOWING SIX (6) QUESTIONS1. A city of 100,000 people in arid North Africa is faced with a severe and chronic watershortage. They have no additional water resources that can be developed from either surface orground sources, except their sewage. Presently, they treat their sewage by primary sedimentationand secondary treatment by activated sludge and then chlorine disinfection (10 mg/l dose, 60'contact time) and simply discharge it to a river (usually an otherwise dry riverbed).The city is considering the emergency reclamation and reuse of their sewage for beneficialpurposes, including its possible use as both potable and non-potable water supply. They proposeto use advanced treatment processes to reclaim the treated sewage effluent. As an authority on water, sanitation and health, the city has asked you to address the followingquestions.a. What are the potential microbial risks of using reclaimed wastewater? Which microorganismsare most important as health risks? How would or could you find this out if it was not clearlyknown?b. City leaders want to know if hepatitis E virus is one of the microbes posing a risk fromreclaimed sewage. What is your judgment of such a risk and what is the basis for your judgmentof this risk? How would you try and find out about this risk?c. What beneficial uses of the reclaimed water would you recommend or allow?Would this include use as: (i) drinking water? (ii) irrigation water for parks, other greenspaceand household lawns? (iii) industrial cooling water? Other?d. What do you recommend for treatment of the wastewater to produce reclaimed water for therecommended beneficial uses in part c? e. Do you recommend the same treatment scheme for all beneficial uses of the water? f. What are the expected microbial reductions, as log10 and/or percent, of the major classes ofsewage-borne pathogens of public health concern for each of the treatment processes yourecommend and the entire treatment scheme(s), beginning with the raw sewage? If possible,1provide quantitative data and show calculations.g. What types of management, operations, surveillance and other measures would yourecommend to assure or verify that the reclaimed water was consistently safe? Would thisinclude maximum allowable limits of specific pathogens, pathogen groups and/or microbialindicators? If so, which ones, at what levels and why? How would you monitor for them orwhat other parameters would you propose to monitor as surrogates for them?2. A country in southern Africa is experiencing a persistent and pervasive epidemic of choleraresulting in tens of thousands of cases of disease and thousands of deaths. You are called in toimmediately take charge of the situation, investigate, determine what to do, coordinate actions,determine the best environmental health measures to control, contain and eventually eliminatethe cholera outbreak, propose measures to prevent future outbreaks and develop a system to trackand document progress in these efforts. You are charged with writing and implementing adetailed plan of action and coordination for key elements of the plan and all of its relevant andresponsible parties. Develop a plan of action, starting with a description of the action plan and its various elements,the participants in the action plan and the kinds of resources that need to be identified andmobilized to launch the plan. Include in the plan:(a) the identification of specific team members and their roles and responsibilities, (b) the intervention approaches, specific actions and actual methods and materials to control andcontain the outbreak and to manage cholera cases, (c) plans and actions to prevent further spread and achieve containment of the outbreak.(d) the approach to determining if the action plan, once implemented, is reducing cholera diseaserisk and burden, including the analytical approaches and methods to track progress in controllingthe epidemic.A description of the plan and its essential elements, the players in it, its implementation strategy,its tracking elements, the expectations from implementing it and the interpretation of possiblefindings as you track progress constitute the answer to this question. Everybody is waiting for you to take the lead on this...NOW!3. In many parts of the developing world the feces of agricultural animals including those forfood are either not managed, managed poorly, are considered a resource as fertilizer for variousplants and are often used in various rituals such that there is human contact with the material.There is growing concern that such animal feces is a risk to human health, resulting in directhuman exposure causing infections, illness and death, exposure from contaminated surface andground water, exposure by consumption food crops, and other routes of human exposure (e.g.,vectors). As an authority on environmental health and sanitation, you have been tasked withidentifying and ranking the human health risks from current animal fecal waste managementpractices in different settings in developing countries, to identify or develop guidance on how tominimize the human health risks from current practices and to identify “best managementpractices” for such fecal wastes from different sources and in different settings to minimizehuman health risks a. What are the pathogens of greatest risk that could be present in fecal wastes of different foodand related agriculture animals and at what levels or concentrations?2b. What management systems and operating conditions for them would you recommend tocontain and/or reduce pathogens in these fecal wastes in different settings and why wouldyou recommend them? c. To what extent do the different management
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