Submitted to Journal of Health Population and NutritionRevision October 14th 2005

ONE SOLUTION TO THE ARSENIC PROBLEM:A RETURN TO SURFACE (IMPROVED DUG) WELLS

Sakila Af. Joya, Bivash C. Barmon, Ariful Islam, Golam Mostofa, Altab Elahi, Jabed Yousuf , Golam Mahiuddin#, Mahmuder Rahman, Quazi Quamruzzaman

Dhaka Community HospitalWireless Railgate

Dhaka, Bangladesh

Richard WilsonDepartment of Physics*

Harvard UniversityCambridge, MA 02138, USA

Address to whom correspondence should be addressed# Address to whom requests for reprints should be sent

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Abstract

The problem of contamination of drinking water in Bangladesh by arsenic is a major catastrophe that dwarfs most other man made disasters. The national policy is to encourage a return to the plentiful surface waters in so far as possible without encountering the problems of sanitation that led to the use of ground water in the first place. In this paper we describe the procedure and the success of the Dhaka Community Hospital team in implementing sanitary, arsenic free, dug wells. The capital cost per person for running water is between $5 and $6 per person. Since it seems that other groups have not had the same success, we include a detailed description of the recommended procedures that others may follow in appendix 1. A detailed cost breakdown is provided in appendix 2 and a description of the initial chemical and bacteriological measurements is in appendix 3.

Key words: arsenic, dugwells, sanitary, coliform,

Introduction

The arsenic problem in Bangladesh has been widely discussed . About 20-40 years ago people in Bangladesh the past 40 to 50 years, have been abstracting ground water by sinking tube wells . The wells were cheap. The water seemed to be free of the bacteria that had caused cholera. This seemed to be a magic solution to the nation’s drinking water problems. But it produced its own very serious problems. About 30% of the wells contained too much arsenic. Physicians at Dhaka Community Hospital (DCH) became aware of the ailments caused by arsenic as early as 1982. But world attention was not brought to bear until the first (of eight) International Conference on arsenic held by Dhaka Community Hospital in January 1998 held jointly (in Dhaka) with Jadavpur University, Kolkata1. At that time also, DCH and Uposhon carried out a 500 village rapid assessment2. DCH and Jadavpur University carried out detailed surveys in many villages3 . At that time there were several “obvious” conclusions.

(1) A short term solution might be acceptable if it was implemented on a wide scale at once.(2) A long term solution should fit into a national water policy(3) There was no reason for delay; short term solutions should be implemented at once.(4) A simple return to unsanitary surface waters is undesirable

1 Reports of each of these conferences have been widely circulated and are, for example, available on the web at http://phys4.harvard.edu/~wilson/arsenic/conferences/arsenic_project_conferences.html

2 Arsenic in Bangladesh: report on the 500 Village Rapid Assessment Project, Published by Dhaka Community Hospital, May 2000

3 Groundwater arsenic contamination in Bangladesh: summary of 239 days field survey from August 1995 to February, 2000 and 27 days detailed field survey information from April 1999 to February 2000Printed by and available at: School of Environmental Studies, Jadavpur University, Calcutta - 700 032, India, Dhaka Community Hospital, Dhaka –1217, Bangladesh, Richard Wilson Harvard University, USA.Also available on the web at:http://phys4.harvard.edu/%7Ewilson/arsenic/countries/bangladesh/BANGLAREPORT.html

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The proposals that were made at once were:(i) to have a national survey of wells, (ii) encourage well switching (use of a well without arsenic) and (iii) install temporary (household scale) arsenic removal devices. (iv) Use deep wells (deep enough to penetrate a clay layer)

However 7 years later, there was delay, the short term quickly became a long term and there are many villages still without pure water. Well switching has been variable: some estimates are that only 30% of villagers switched wells. Columbia University scientists find that the number is 60% in the area they studied, perhaps because they had an intense village education program. Moreover it is strongly suspected that continued pumping from a safe (green) well can bring arsenic laden water into that part of the acquifer. The arsenic removal devices proved too hard for many villagers to use and many of them were unsatisfactory and were abandoned4. And some scientists have cautioned against indiscriminate use of deep wells. Although the arsenic contamination of this deep layer is at present much smaller than the arsenic contamination of the ordinary tube wells at a depth of 40 meters it is unclear whether it will always remain so.5 In Dhaka continuous extraction of ground water is non rechargeable at the same rate of extraction, and has resulted in severe lowering of the ground water level. According to the WASA report 2003 6, the ground water level that was 11m in 1970s went down to 20m in 1980s.

In 2003 the Government of Bangladesh (GOB) promulgated a “National Water Policy”7 which gives priority to surface water use among other options. These surface water options seem to be:

1) Encouraging a return to surface (dug) wells (DW), but with a strict adherence to WHO sanitary standards. 2) Use of sand filters to filter pond water (PSF) or river water (RSF)3) Storage of rain water

In all solutions, involvement of the local community seems essential. DCH is particularly suited to such pilot projects because each of their 40 local clinics can act as a focus for action. DCH chose the second of these surface water solutions, the use of dug wells, for this first demonstration facility in the Pabna district. This report describes three phases of the work starting in the year 2000, till 2003, and some indication of further developments in another district since 2003. Further tests on some of the wells in 2004/5 are also included. Other groups are actively studying other solutions, including use of deep wells, and we make no premature claim on whether, or where, a particular solution will prove to be the best.

The DCH Dug well Demonstration (Pilot) Project

Dugwells have been used for time immemorial, but were replaced by tube wells because of simplicity and in particular freedom from bacterial contamination without the apparent

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necessity of careful maintenance. A return to dugwells seems, therefore, an obvious possibility. However this has not been uniformly successful. This project was begun to demonstrate that it is possible to have bacteria free wells if due care is taken and in particular if WHO requirements were followed.8 While this is obvious in a temperate climate such as UK, it is far from obvious in the tropical village conditions of Bangladesh. There were therefore several aims. Will the wells be bacteria free? Will the wells be free of arsenic and other undesirable chemicals? What will be the cost? What maintenance is necessary? Are there other conditions such as limited choice of sites that are necessary to achieve these aims? Will the wells be acceptable to the people? After the start of the project DCH noted that the Bangladesh government electrification program had already brought electricity to 50% of all villages and has the aim of bring electricity to them all by 2020. This makes it easy to install an electric pump to raise the water to a storage tank, from which it is gravity fed by pipeline to a number (6 or more) individual houses. This has proved very popular and is a major step toward the widespread acceptability of this solution. It is interesting that Ahmad et al.9 found by survey that the availability of running water is more important in public perception than the fact that the water is arsenic free. The Bangladesh Arsenic Mitigation Water Supply Project (BAMWSP) has also stated its intention of providing 30 pipeline systems10. However we have no further information about them.

Although the project was begun in late 1999, it started in full measure in April 2002. In the first phase 39 wells were dug, (or in some cases reconditioned) by February 2003. These wells supplied 631 families and serve 3,250 users. Only one had a pipleine system attached. In phase 2 seventeen new wells were dug and all had the pipeline system installed. Another 518 families were supplied and 2,903 users were served. In phase 3, nine old wells were renovated (brought up to WHO sanitary standards) and one new one dug; all with electric pump, storage tank and pipeline. This supplied another 400 families with 2,400 users.

In all 66 sanitary dug wells were installed in this demonstration pilot project in the Pabna region. This region was chosen for a number of reasons. Firstly, the need seemed great in this area. In several villages all, or nearly all, tubewells showed excessive levels of arsenic. In several villages patients with evident arsenic related lesions had been found. Secondly, DCH has a clinic in Pabna where patients may be seen and water samples analyzed. Thirdly epidemiological studies of arsenic lesions are being studied in this region by DCH together with a group from Harvard University. The general geographical location of these wells is shown in figure 1.

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Procedure for the installation of a Dug Well with Pipeline

March and April, which are the driest months in the country, are the best times for digging a well. During this period, ground water remains at the lowest level so that if the well hits water at that time it will always hit water. We believe that it is crucial to emphasize that DCH does not own the wells. The community owns the wells and is responsible for their installation and maintenance. DCH merely facilitates these, and in this paper reports upon them. Because of the crucial importance of the full participation by the community, and the fact that this has not always been achieved, we outline the procedures DCH have adopted to ensure this responsibility. DCH found that there were several major distinct activities, none of which can be omitted if success is to be assured: Community mobilization, Committee formation, Training of community workers and the caretaker, Site selection, Drawing of water supply network,

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Installation of dug well and pipe network, Community meeting, Water quality monitoring. These are detailed below.

Community mobilizationVarious mobilization and motivational activities were conducted, such as courtyard

meetings, to increase public awareness. Several meetings with the community were held in each village. Local Government of Bangladesh (GoB) elected persons and influential local people were present in meetings along with the DCH personnel. Community people including women, the poor and arsenic patients shared their situation, needs, opinions and preferences about mitigation options with DCH and others.

Committee formation

In each village a committee was formed for the supervision of each stage in the implementation. Each committee was responsible to maintain the option provided to them. DCH and the committees worked together to plan option installation and maintenance. The committee accepted responsibility to collect the community contribution. The committee decided the charges for water use for each family. A caretaker collected money from water users (usually 20 Tk or 35 cents a month for each family). Each family was provided with a water card for payment. Training

Local mistris were selected for construction and maintenance of the options. They were trained on construction work options by DCH trainers. DCH trainers also trained caretakers and users of options.

Site selectionSites for wells were selected in areas highly contaminated by arsenic. This was done after

consultation with the community. Preference was given to sitting the wells near the patient families and the poor. All 66 sites satisfied guidelines provided for site selection, including but not limited to:- Preparing a Dug Well 30-40 ft away from the latrine and dumping ground of waste materials- Animals are penned away from the Dug Well- The Dug well is installed at a safe distance from cropland and industrial area etc.

A detailed check list for adequacy of the site selection is being prepared taking account of the expereince gaines so far

Installation

A hole is dug with a diameter of about 36 inches. The depth of the well varies from place to place. A ring of cement or baked clay is set from bottom to top and the rings are joined (sealed) by cement to keep the well water safe from contamination from contaminated surface water. An apron of about four feet is made around the head wall and a 30-40 feet drain is

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constructed at the ground level to avoid water seeping into the well around the head wall. An electric pump pumps water from dug well to an overhead reservoir of 3,000 liters. This overhead tank is installed on an iron stand, 15 feet tall. The stand is fixed on the ground with RCC work. A main water supply pipe (made of 3 /4'' plastic) is connected with the tank for distribution of water to the household level. A GI pipeline of ½ inch plastic is connected with the main line to supply water to each individual household. 40-50 households are connected with a single main supply line. To prevent accidents, during construction of Dug Well, due to collapsing of side-soil and occasionally asphyxiation from carbon dioxide and methane gases- rope, ladder, a Bosun’s chair and other safety equipment are kept at the site. A 30-40 feet drain is constructed at the ground level to avoid water seeping into the well around the head wall.

Water quality monitoring and the Importance of Measurements

One of the most important functions of the village committee is the continuous monitoring and guarantee of water quality according to quality guidelines prepared by DCH in consultation with experts and according to the WHO guide lines. In this the village committee can call upon the advice and help of Dhaka Community Hospital and others. This aspect of the implementation is so important, and so often neglected that we emphasize it in a separate section here.

Failure to make adequate measurements has been at the heart of the tragedy of Bangladesh. For 20 years no one measuremed the arsenic levels in even a small sample of the millions of tube wells until it was too late. More recently many small-scale arsenic removal devices were installed without adequate measurements to demonstrate their efficacy. Some NGOs returned to surface waters without following WHO sanitary guidelines and without measurement of possible bacteriological contamination. For this, and other, reasons DCH have insisted on measurements from the outset. Because of the past failures in this regard, DCH recommend that a copy of all measurements be publicly available, for it is important that not only the individual who has the well be convinced, but also DCH as a whole and through DCH the wider community. The measurements of this pilot project are available in appendix 3 and more detail is available on the web at http://DCHtests.arsenic.ws.

Measurement of Arsenic Concentrations:

It is extremely unlikely that aerated surface waters will have the same level of arsenic that the deeper wells do. One present speculation is that the arsenic is dissolved by the water when there is an anoxic environment11 and having a well open to the air is therefore helpful. Indeed there was no report of chronic arsenic poisoning in the thousands of years of use of dugwells before the tubewell came into use. Dipenkar Chakraborti reports12 on measurement of 700 dugwells in Bangladesh and West Bengal and finds that 90% have levels less than 30 ppb and only a few have 50 ppb. More recently in phase 1 of the “Risk Assessment of Arsenic Mitigation Options (RAAMO) by the Arsenic Policy Support Unit found that 1% of dugwells they surveyed had arsenic above 50 ppb but none with the very high levels found in ordinary tube wells.13 This suggests that the frequency of arsenic measurement is less important than the

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measurements of coliform bacteria. The problem with the requirements for arsenic measurement is that we are asking to reliably measure levels of arsenic at 50 parts per billion in water when other chemicals are present at much higher levels. Laboratory instruments can, in principle, achieve this with no difficulty by gas chromatography (with $30,000 cost for each equipment) but this involves taking samples in the field and bringing them back for measurement. A simple calculation performed 4 years ago showed that there was barely enough equipment in Bangladesh to measure every well every 1000 years! Worse still, an interlaboratory comparison by the International Atomic Energy Agency showed, in an unpublished draft report14, frightening disagreements. Measurements in the field are even worse. The field kits depend upon a visual identification of the color. This depends critically upon the training of the personnel. A group of Bangladeshi and Bengali scientists report on their comparisons in 2002 and insist that “facts and figures demand improved environmentally friendly laboratory techniques to produce reliable data”15 . There is hope on the horizon. More recent (2005) laboratory comparisons of water samples with the IAEA laboratory show that several laboratories are in full agreement Some laboratories seem to fail in the precision of the measurements. The lower precision (25%) is not important for the present purpose. Columbia University scientists find that the Hach kit can be reliable if used in a slightly different manner than recommended by the manufacturer16 but this information was not available to DCH at the time.

It is not anticipated that arsenic levels will be high in surface wells, whether tube wells or dug wells, and it has been suggested that aerated dugwells have even less arsenic. While measurement is important, it is less important for dugwells than the measurement of coliform bacteria. For the measurements in appendix 3, the Silver Diethyldithiocarbamate Method was used. It is well known that this is difficult to use below 5 ppb. Cross calibrations with measurements at Harvard University (but not using these exact samples) using gas chromotography showed the measurements to be unreliable below 5 ppb. For this reason only an upper limit is quoted in appendix 3. For future work, samples are being sent to other laboratories and a better detection apparatus will be obtained.

The measurement of Coliform Bacteria:

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? PK Aggarwal, M Dargie, M Groening, KM Kulkarni,and JJ Gibson “An Inter-Laboratory Comparison of Arsenic analysis in Bangladesh” IAEA draft report available at:http://phys4.harvard.edu/~wilson/arsenic/measurement/arsenic_inter_laboratory_comparison.pdf15

? Rahman M., Mukherjee D., Sengupta M., Chowdhury U., Lodh D., Chanda C., Roy S., MD. Selim, Quamruzzaman Q., Milton A., Shahidullah S., MD. Rahman T., Chakraborti D. (2002)“Effectiveness and Reliability of Arsenic Field Testing Kits: Are the Million Dollar Screening Projects Effective or Not?” Journal of Environmental Science and Technology 2002; 36(24); 5385-5394..16

? Cheng Z., Van Geen, A, Chuangyong, J., Meng, X., Siddique A., Ahmed K.M. and Ahmed K.M. Performance of a household-Level Arsenic removal System during 4 months Deployment in Bangladesh,. Environ. Sci. Tech. 38:3442-3448 (2004)http://phys4.harvard.edu/~wilson/arsenic/measurement/ES_and_T.pdf

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The measurement of coliform bacteria is, in principle, much simpler than the measurement of arsenic concentrations although again the reliability in practice is critically important and the frequency of measurements needed for the dug wells is greater than the needed frequency of arsenic measurements. However, many users of dugwells have found considerable coliform bacteria. There is general agreement that measurement of coliform bacteria can be reliable. For the first measurements Dhaka Community Hospital had no equipment of their own. Measurements by other institutions were expensive and unreliable and are not reported here. However in 2001 we acquired a “Delagua” kit17 designed at the University of Surrey and used it for all measurements for the 66 wells reported here. More recently the coliform vial from a JAL-TARA18 measurement kit from CLEAN INDIA in New Delhi has been used to give an initial qualitative test to determine whether a full measurement is necessary. The initial measurements of the 66 dug wells in this project are shown in appendix 3. They were repeated by DCH every three months for a little over a year before handing over to the community managers. The initial set of 5 – 6 tests is available on the web. Unfortunately the date of disinfection (with lime) was not recorded but it is possible that it was shortly before the measurement so that the measurement might not be a good indication of long term behavior. This may explain the fact that the measurements of total coliform were low and of faecal coliform were consistently 0 whereas the tests discussed in the next paragrpah were high..

In 2004 questions were raised about the quality of the DCH wells. Accordingly 20 of the wells were tested again frequently for a year (July 2004 to June 2005). A different coliform measuring equipment was used – from MacConkey, because the culture medium, MacConkey (purple) broth is more readily available in Bangaldesh, than the culture medium for the Delagua kit (membrane Lauryl Sulphate Broth). This time, tests were only made for faecal coliform and not for total coliform. The measurements revealed problems of which we were not aware. It can be seen from a plot for 6 of these wells in figure 2 the coliform bacteria levels were high in July 2004, and were therefore in violation of the present standard, but soon dropped to less than 10 structures per 100ml (although one rose again).19 It is unclear why. This was the first time that the “multiple tube” method was used and the first meaasurement may have been an error. It is also possible that the guardians of the wells had not applied lime when appropriate during the previous 6-12 months. These faecal coliform indicate that the water may be contaminated with human or animal wastes. In principle both the US EPA and WHO state that there shall be no faecal coliform.20 Unfortunately the dates when liming and other maintenance was performed was not recorded. Work is continuing to understand the reasons for the high levels when they occur; and this will be used in recommendations for frequency of monitoring.

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The capital cost of the wells was about $70,000. This cost does not include the cost of DCH planning and supervision. The capital cost is falling with time as we learn how to use indigenous materials and labor. Detail of the cost breakdown for different types of installation is shown in appendix 2.

Note to EditorIt seemed best to us to have this crucial detail in appendix 2. But you may prefer to omit it entirely and we will merely say that it can be obtained from DCH or from the arsenic website.

Measurement of Manganese and other chemicals21

The first measurements in appendix 3 were of those pollutants that were easily measured with the Delagua kit. But recently it has been suggested that manganese is a serious problem in many surface waters and has effects upon health that can be as serious as those of arsenic. Accordingly at our request BUET made a search for manganese. The WHO standard is 0.4 mg/l and most of the measurements were below 0.1 mg/l. In two wells at one time only, the measurement was up to 0.6 mg/l. Details of the measurements are posted on the website22.

Acceptability

APSU performed a “Social Assessment” survey on the acceptability of the dug wells they tested23 79% stated that they were acceptable. No specific surveys have been undertaken to provide a quantitative level of acceptability.in this study. However on the various visits to the villages, by one or more of the authors, subsequent to installation there has uniformly been enthusiasm. Persons from neighboring villages have requested the help of DCH. In particular enthusiasm has been shown for the distribution of water by pipeline because the distrance to fetch water is important. This was not an issue or question in the APSU study (but see their table 4.7) . Since the addition to the cost is modest, and it enables more people to be served by the same facility, we encourage that this improvement be undertaken at the same time.

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We feel that any further discussion and verification of acceptability should be accompanied by a “willingness to pay” for the improvements

In figures 2,3 and 4 below are shown photographs taken on one of these visits in 2004. They show respectively a typical dug well with attached tube well, the water tank from which gravity feeds the houses, and the tap with pure water in a lady’s kitchen for the first time in history.

Figure 3 Figure 4 Figure 5

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Subsequent maintenance

It is a part of the whole principle under which DCH are helping the villages that the villages own the wells and have the responsibility for their good operation. Nonetheless in the short term DCH help. DCH has suggested a careful visual inspection every three months Frequent measurements have been made on the 66 wells and on subsequent wells dug with DCH guidance, so that the issues may be fully understood. In long term, many fewer measurements are likely to be necessary. No problems of arsenic and manganese contamination have been found, and it is unlikely that they would increase rapidly. Therefore we suggest that a complete chemical analysis need not be frequent – maybe every 2 years. But, as noted above, bacteriological contamination can be serious and can change fast.

So DCH is urging the community to call for measurements if and when any of the following occur: - after a visual inspection (to be carried out every three months) the well casing, or the apron- surrounding the well seems cracked- the water begins to smell foul- the turbidity increasesDCH is preparing a detailed advisory and check sheet for this maintenance. Since as noted in appendix 2 the maintenance can be an appreciable cost item, this remains an important consideration for further study and elucidation.

Long term

We have always noted that a choice between acceptable actions could well be guided by whether the action leads to a long term solution. In the long term we hope that most citizens of Bangladesh will have access to publicly supplied pure running water where the concerns about purity are handled centrally. We note that dug wells with a piped water supply have traditionally been a step in this direction in many countries. For example, in one English village in which one of us lived for several years, an open dug well was used for centuries with a bucket for collection. This well was covered and a pump installed about 1920; in 1939 a windmill was installed to pump up water to a tank from which a pipe led to every house and cottage. In 1945 a small petrol engine was installed for use when there was no wind. About 1960, a main water line came within a mile of the village and it was easy to make a spur connection to the village supply network. This, of course would also apply if water from a deep well were pumped to an overhead tank for distribution.

Conclusion

The use of a sanitary (dug) well has been shown to be a satisfactory and reliable solution for the provision of bacteria free, arsenic free, and running water in several Bangladesh villages. The capital cost is about $5 to $6 per person. Crucial steps in achieving arsenic free and bacteria free water seem to be:Selecting a site suitable for a dug well (one in peat is sure to smell!)

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Strict adherence to sanitary standards as discussed for example by WHOEnsuring community participation, ownership and maintenance of each well

This pilot project has can be, and is being, extended considerably in the Pabna region where there has been word of mouth communication creating demand by people from other villages. The installation has been supervised by DCH personnel, but there is a steady increase in the understanding of the villagers themselves. With the financial assistance of UNICEF, DCH have also supervised (since 2003) the installation of 137 wells (but only 3 with pipelines) in the Sirajdikhan upazila.24 In principle, sanitary dug wells could be installed in many other parts of Bangladesh. DCH has at the time of writing supervised 224 Dug Wells, bringing pure water to perhaps 50,000 people – but only 0.1% of the people in Bangladesh who are in need. In all of these the same careful procedures are adopted. The original 66 dug wells described in this paper were free of faecal coliform bacteria, and very low on total coliform, but about 18 dug wells dug later in the Sirajdikhan upazila had contamination after an unusually severe flood. These were retreated by DCH and now all of them are safe and measurements show a zero or very low coliform bacteria count. In 50 of these wells, the measurement of the bacteria count (using the Delagua kit) and contamination by other metals has been verified by measurements by the International Center for Diarrheal Disease (ICDDRB). These are noted in the list of measurements for these wells that are on the arsenic website at:http://phys4.harvard.edu/~wilson/arsenic/remediation/dugwells/Dugwell_tests_for_UNICEF.xlsor a shortcut: http://DCHtests.arsenic.ws

As the Dug Well option is further implemented it is important to use indigenous materials and measurement techniques whenever possible. This concept was used in this “pilot” project. A part of the pilot project was clearly to demonstrate all aspects of a remediation method - including a measurement of its cost effectiveness. However, the resources of DCH are limited, so that for widespread use of dug wells it will be necessary for other groups to come forward, learn the details of the simple technology, and to work with, and supervise the villages in the same way. Hopefully some group will take this next step during the coming year.

In addition to the dug wells, Dhaka Community Hospital has started to provide other surface and sub-surface water-based alternative safe water options – 5 River Sand Filters (RSF), 9 Pond Sand Filters (PSF), and 1,122 Rainwater Harvesting (RWH) units in the arsenic affected communities in collaboration with GoB, UNICEF and donor agencies. All work satisfactorily. These pilot, demonstration, projects will also be available for others to follow. DCH also provides training on arsenicosis and arsenic problems through its Institute of Family Health, including training for oversees medical personnel e.g. the Nepalese Health Department. These will be described in forthcoming papers.

Acknowledgments

It is a pleasure to acknowledge the help of the many others who made this work possible. First and foremost, the OPEC fund for International Development and other donors who made the project possible. CLEAN INDIA of New Delhi, started by Dr Ashok Khosla, has been helpful in providing at low cost reliable test equipment. In addition Richard Wilson thanks all

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the staff of Dhaka Community Hospital for their hospitality.

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APPENDIX 1 DETAILED GUIDELINES FOR THE CONSTRUCTION OF A DUG WELL

Note to editor. If you prefer not to include Appendix 1 we will here refer the reader to the arsenic website and to DCH itself.

A. Dug Well (DW) Survey

1) A survey and collection of records (number, location, present situation) of any existing Dug Wells in the area should be made

2) The reason that a Dug Well is unused should be determined. Attempts should be made to renovate an existing Dug Well if possible

3) In case of non-availability of any such records, a test borehole should be made to make a bore log at the site.

B. Site Selection

The following factors must be considered in selection of the site: –

1) Areas of peaty soil should be avoided for the Dug Well as these cause the water to have an unpleasant taste and smell.

2) There should be a stable soil layer at the top (a clay layer is preferable)3) Presence of sandy layer within 9 to 12 m (30-40') from ground level is desirable4) The site must be at least 30' away from any existing latrine5) The site must be at least 30' away from pond6) The site must be at least 30' away from a river

C. Dug Well Configuration

1) Inner diameter is 88.2 cm (3') and outer is 1.17 m (4')2) Depth of Dug Well varies with the soil condition and water availability of the site. Depth

should be such to ensure 1 to 1.5 m (3' - 6') water column at the driest period3) Height of concrete ring is 29.4 cm (1')4) Height of head wall is 1 m (3.5') above ground level5) About 59 cm (2') apron is provided all around the well 6) 1.17 m (4') x 75 cm (2.5') platform is provided for Tube Well installation beside apron7) Length of drain pipe attached with the Tube Well platform varies from 1.5 m to 3 m (5' -

10')8) Dug well should be covered to protect it from outside contamination ensuring proper

ventilation and sunlight. The cover is made following WHO guidelines. Or a 0.4m (1’4”) wire mesh should be placed on the head wall, for ventilation and a roof on the top with translucent sheet to facilitate illumination and sunlight.

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D. Manpower

1) Trained workers (mistris) must be used for construction2) 6 workers (mistris) should be employed for construction work- 1 head mistri, 2 assistant

mistris and 3 local persons to help the mistris so that they become trained after construction of a few Dug Wells.

E. Construction

1) The Dug well should be dug manually2) The Dug well should not be constructed to a pre-specified depth. The required depth

will depend on the soil and water table conditions. Instead it is better to construct the dug well in the dry season, with the objective of achieving about two meters of water in the Dug Well upon completion. This procedure will ensure a sufficient depth of water to remain serviceable year-round.

3) Concrete rings are inserted after completion of digging4) Where the sub-soil formation is not stable enough, the method of caisson driving (widely

used in bridge construction), may be used5) Where the self-sinking method is used, the first ring of the Dug Well should be robustly

fabricated with a cutting edge 6) To prevent sand boiling rings should be jointed together using cement mortar inside and

outside of rings and joint-less flexible PVC, floating pipe can be connected with the Tube Well. Iron rings, connected with concrete rings, can be used to hold this flexible pipe

7) To prevent accidents, during construction of the Dug Well, due to collapsing of side-soil and occasionally asphyxiation from carbon dioxide and methane gases - rope, ladder, Bosun’s chair etc should be kept at the site. No one should be allowed to work alone.

F. Water Quality

1) 30 cm (1') layer of brick chips are placed at the bottom of the well. 1.8 cm or 3/4'' chips are placed at the bottom in 10 cm (4'') layer, 1.3 cm (1/2'') chips are placed in next 10 cm (4'') and 2.5 cm (1'') chips are placed in the last 10 cm (4'').

2) Water parameters should be tested in the laboratory at least two times a year. These parameters should be: pH, color, turbidity, iron, manganese, chloride, total dissolved solids, total coliform (TC), fecal coliform (FC) and arsenic.

3) Well water is cleaned two times a year. For this 2 kg lime is thoroughly mixed with 35 L of water and then it is poured in the well. The well water is stirred and then kept unused for 3 to 4 days. After 3 days the well is unloaded. The well is then filled with fresh water seeping from the aquifer.

G. Maintenance.

The village must form a committee to be responsible for regular maintenance. The best time for cleaning is the period between March and April. 2 kg of lime is thoroughly mixed with 35 l of

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water and then it is poured into the well. The well water is stirred and then kept unused for 3 to 4 days before use. Workers must be trained for this task. If maintenance is not regularly continued it is possible, even likely, that the coliform count will rise and the water become unsanitary. If all requirements are met, we have found that water is of good quality. However the requirement of testing [(3)] should not be omitted.

DCH is preparing a checklist to make sure that these requirements are followed. A typical drawing of a village layout, as posted for example in the nearest clinic, is shown in the figure below.

Note to EditorIt seemed best to us to have this detail in appendix 1. It is a typical plan at the DCH clinic office for consulation by the villagers. But you may prefer to omit it entirely and we will merely say that it can be obtained from DCH or from the arsenic website.

Figure 6

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Electric pump

Overhead water tank

APPENDIX 2

Note to EditorIt seemed best to us to have this crucial detail in appendix 2. We are continually asked about the costs and this seems to be the place to put them and the right amount of detail. But you may prefer to omit it entirely and we will merely say that it can be obtained from DCH or from the arsenic website.

Typical costs of different types of Dug Wellsexcluding DCH supervision

1 2 3 4 5 6 7 8 9Sl Type of Dug Wells Tap

Points Families Covered

Popul.Covered

Total Cost Per person Cost In:

Average Approx Approx. In Taka USD$

TakaCl.6/Cl5

USDCl.7/Cl.5

1 Improved New Dug Well+ Pipeline Network+ Water Tank(Steel) + Water Tower (Steel Column)

8 50 250 83,260.00 1388 333.00 5.5

2 Improved New Dug Well+ Pipeline Network+ Water Tank(Steel) + Water Tower (Brick Column)

8 50 250 92,760.00 1544 371.00 6.2

3 Improved New Dug Well+ Pipeline Network+ Water Tank(Steel) + Water Tower (RCC Column)

8 50 250 98,610.00 1643 394.44 6.5

4 Improved New Dug Well +Hand Tube Well 1 15 75 58754.00 979 783.00 13.05 Recondition Dug Well + Pipeline Network + Water

tank (Steel) + Water Tower (Steel Column)8 50 250 50,350.00 839 201.00 3.3

6 Recondition Dug Well + Pipeline Network + Water tank (Steel) + Water Tower (Brick Column)

8 50 250 72,070.00 1201 288.00 4.8

7 Recondition Dug Well + Pipeline Network + Water tank (Steel) + Water Tower (RCC Column)

8 50 250 70,220.00 1170 280.00 4.6

8 Recondition Dug Well + Hand Tube Well 1 15 75 31,394.00 523 418.50 7.0 Note:- 1. Calculated at the rate of 1USD = Tk. 60.00

1818

Table 4Maintenance Cost (per well)

Material Quantity Price Total Tk

Labor charge for cleaning 3 person 400 2000/=

Potash 100 gm 30/=

Lime 3 kg 10 30/=

Repairing and fixing broken, leaking and other damaged parts

1000/=

Total: 3060/= ($51.00) [Calculated at the rate of 1 $ = 60 Thaka ]

The annual expense for maintaining a dug well is modest and is borne by the village community.) A typical cost breakdown is shown in table 4 above. Typically families pay 10 –20 Taka per month (120-240 Taka per year) which usually includes 60 Taka for maintenance , a small stipend for the caretaker as chosen by the village Option Management Committee (OPC) and the electricity bill for the pump.

At the present time the cost of the measurements is borne by DCH.

Cost of full 15 parameter (including Arsenic) test 5500/= Tk ($95) Performed Initially and when needed (biannually)

Cost of Preliminary Coliform test by Clean India(Jal-Tara) $1 each $4 a yearPerformed quarterly

Cost of faecal coliform (FC) measurement is 400/= Tk. ($7) when indicated by Jal-Tara or other test (approximately annually) .

1919

APPENDIX 3

The initial measurements of the first 66 dugwellsMore complete measurements are available at:

http://phys4.harvard.edu/~wilson/remediation/dugwells/DCH_Phase1_Bacteria_tests.xlsor http://DCHtests.arsenic.ws

Dhaka Community Hospital – Pilot Sanitary Dug Well Project – Pabna Region

4

? 6th Report on Arsenic Removal Plants: July 2004 Part B. Follow-up Study on 20 ARPs found to be functional in March 2004, School of Environmental Studies (SOES), Jadavpur University, Kolkata- 700032, IndiaWebsite: www.soesju.org 5

? Report of Groundwater Task Force, Government of Bangladesh, Chairman Dr S.K.M. Abdullah. 2002.6

? Water and Sewerage Authority (WASA) Ministry of Local Government and Rural Development, Government. of BangladeshWASA report of 2003

7 National Policy for Arsenic Mitigation and Implementation Plan for Arsenic Mitigation in Bangladesh Local Government Division Ministry of Local Government, Rural Development & Co-operatives Government of the Peoples’ Republic of Bangladesh March 2004 8

? WHO table of dug well recommendations http://www.who.int/water_sanitation_health/dwq/wsh0306tab8.pdf

9 J.K. Ahmad, B Goldar, and S Misra. Value of arsenic-free drinking water to rural households in Bangladesh. J Environmental Management, January 1, 2005; 74(2): 173-85.10

? Report of Bangladesh Arsenic Mitigation Water Supply Project http://www.bamwsp.org/news5.htm

11 Professor Charles Harvey, MIT, private communication

12 Only a web version of the report seems available.http://phys4.harvard.edu/%7Ewilson/arsenic/countries/bangladesh/Chakraborti/Chakraborti%20Dugwells/Chakraborti%20Dugwells.html

13 Risk Assessment of Arsenic Mitigation Options (RAAMO) Phase 1 report June 2004 Arsenic Policy Support Unit (APSU) Government of Bangaldeshavailable online at: http://www.apsu-bd.org17

? The Delagua coliform bacteria measuring kit from the Robens Centre, University of Surrey UKhttp://www.robenscentres.com/delagua/index.cfm18

? The Jal-Tara pollution measuring kit from Clean India in New Delhi, Indiahttp://www.cleanindia.org/jaltarakit.htm

2020

Department of Environmental Research Laboratory Report

Data : Analysis of Arsenic & Bacteriological test in water samplesMethod of Analysis (Arsenic) : Silver Diethyldithiocarbamate MethodMethod of Analysis (Bacteriolocical) : Oxfam-Delagua Kit Method FC = Fecal Coliform per 100ml; TC = Total Coliform per

100mlDW Name Address Date of Fam

iliesPh As

conc.Cond. TDS Turb

.FC TC Date

Code of Install or Covered (ppm) (us) (ppm) (NTU) ofCaretaker Renovate WHO Guide Line Values 1996 First

Village Union Thana 6.5-8.5 0.01 850 1000 5 0 0 TestingDWH -1 Md. Anowar Master Maddhapara UBM - 01 TBC - 01 1999 Nov 12 7.0 <0.03 234 152 <5 0 1 20.06.01

DWH -2 Ramjan Ali Pramanik Ruppur UBR - 02 TBC - 01 1999 Dec 11 7.5 <0.03 212 138 <5 0 0 20.06.01DWH -3 Md. Akbar Hossain Ruppur UBR - 02 TBC - 01 1999 Nov 10 7.1 <0.03 241 157 <5 0 0 20.06.01DWH -4 Md. Tipu Sultan Kazipara UBM - 01 TBC - 01 1999 Dec 12 7.5 <0.03 265 172 <5 0 0 20.06.01DWH -5 Govt. Idara Bissanathpur UBJ - 03 TBC - 01 1999 Nov 15 7.2 <0.03 354 230 <5 0 2 20.06.01DWH -6 Md. Masum Master Sinduri UBJ - 03 TBC - 01 1999 Dec 14 7.0 <0.03 310 168 <5 0 1 20.06.01DWH -7 Md. Nasir Khan Sinduri UBJ - 03 TBC - 01 1999 Nov 13 7.1 <0.03 241 157 <5 0 0 20.06.01DWH -8 Md. Mirja Abdul Halim Aminpur UBJ - 03 TBC - 01 1999 Nov 10 7.2 <0.03 246 160 <5 0 0 20.06.01DWH -9 Md Jamal Hossain Aminpur UBJ - 03 TBC - 01 1999 Nov 15 7.0 <0.03 260 152 <5 0 1 20.06.01DWH -10 Md. Majnu Mia Aminpur UBJ - 03 TBC - 01 1999 Nov 12 7.1 <0.03 212 138 <5 0 1 20.06.01DWH -11 Md. Hanif Sheikh Kalikapur UBJ - 03 TBC - 01 1999 Nov 15 7.0 <0.03 350 228 <5 0 2 20.06.01DWH -12 Md. Ali Hossain Kalikapur UBJ - 03 TBC - 01 1999 Nov 14 7.0 <0.03 235 153 <5 0 1 20.06.01DWH -13 Md. Kader Mondal Kalikapur UBJ - 03 TBC - 01 1999 Nov 10 7.0 <0.03 215 140 <5 0 0 20.06.01DWH -14 Md. Samsur Hossain Nayabari UBJ - 03 TBC - 01 1999 Nov 14 7.2 <0.03 198 129 <5 0 1 20.06.01DWH -15 Md. Jabber Master Nayabari UBJ - 03 TBC - 01 1999 Dec 12 7.1 <0.03 263 171 <5 0 0 20.06.01DWH -16 Md. Abdur Rahman Tangbari UBJ - 03 TBC - 01 1999 Dec 10 7.4 <0.03 325 211 <5 0 3 20.06.01DWH -17 Md. Sohorab (Police) Tangbari UBJ - 03 TBC - 01 1999 Dec 13 7.0 <0.03 349 227 <5 0 0 20.06.01DWH -18 Md. Jahur Ali Tangbari UBJ - 03 TBC - 01 1999 Nov 13 6.9 <0.03 285 185 <5 0 3 20.06.01DWH -19 Md. Lutfor Rahman Tangbari UBJ - 03 TBC - 01 1999 Nov 15 7.0 <0.03 168 109 <5 0 0 20.06.01DWH -20 Md. Mojhar Sheikh Kabaskanda UBJ - 03 TBC - 01 1999 Dec 10 7.0 <0.03 365 237 <5 0 0 20.06.01DWH -21 Md. Sohorab Ali Kabaskanda UBJ - 03 TBC - 01 1999 Dec 15 7.0 <0.03 265 172 <5 0 0 20.06.01

19 Details are available on the arsenic website at http://DCHtests.arsenic.ws

20 Drinking Water Standards an Health Advisories EPA 822 B 00 001 (2000) http://www.epa.gov/safewater/mcl.html#mcls

21 A. Opar, A. Pfaff, A.A. Seddique, K. M. Ahmed, J. H. Graziano, and A. van Geen Responses of 6500 Households to Arsenic Mitigation in Araihazar, Bangladesh Submitted to Health & Place, May 31st, 2005

22 At http://DCHtests.arsenic.ws

23 Risk Assessment of Arsenic Mitigation Options (RAAMO) Phase 1 report June 2004 Chapter 4 Arsenic Policy Support Unit (APSU) available online at: http://www.apsu-bd.org/chapter_4.pdf

24 These UNICEF sponsored wells are formally included in the APSU study but none of the randomly selected clusters were in the upazilla and none were installed by DCH. The entry referring to DCH and the implications of their table 3.2 are therefore incorrect. Moreover, we believe that APSU erred in not distinguishing those wells where WHO guidelines had been strictly followed and those that had not.

2121

DWH -22 Md. Jalil Sheikh Kabaskanda UBJ - 03 TBC - 01 1999 Nov 10 6.9 <0.03 282 183 <5 0 1 20.06.01DWH -23 Md. Juran Mondol Kabaskanda UBJ - 03 TBC - 01 1999 Dec 13 6.8 <0.03 320 208 <5 0 2 20.06.01DWH -24 Md. Monnaf Sinduri UBJ - 03 TBC - 01 1999 Nov 12 7.0 <0.03 315 205 <5 0 0 20.06.01DWH -25 Md. Abdur Rajjak

MasterNatiabari UBJ - 03 TBC - 01 1999 Dec 15 7.0 <0.03 252 164 <5 0 0 20.06.01

DWH -26 Md. Sahadot Hossain Natiabari UBJ - 03 TBC - 01 1999 Nov 10 7.0 <0.03 346 225 <5 0 0 20.06.01DWH -27 Md. Rohmot Ali Rajnarayonp

urUBJ - 03 TBC - 01 1999 Nov 10 7.2 <0.03 292 190 <5 0 2 20.06.01

DWH -28 Md. Ali Saheb Rajnarayonpur

UBJ - 03 TBC - 01 1999 Nov 10 7.0 <0.03 304 198 <5 0 3 20.06.01

DWH -29 Md. Torab Ali Rajnarayonpur

UBJ - 03 TBC - 01 1999 Dec 11 7.1 <0.03 269 175 <5 0 1 20.06.01

DWH -30 Md. Sattar Sheikh Sibpur UBJ - 03 TBC - 01 1999 Nov 10 7.3 <0.03 214 139 <5 0 0 20.06.01DWH -31 Md. Ahmed Ali Sibpur UBJ - 03 TBC - 01 1999 Dec 9 7.2 <0.03 198 129 <5 0 0 20.06.01DWH -32 Md. Mirza Ruhul Amin Aminpur UBJ - 03 TBC - 01 1999 Dec 15 7.0 <0.03 282 183 <5 0 2 20.06.01DWH -33 Md. Harun Uddin Aminpur UBJ - 03 TBC - 01 1999 Dec 12 7.0 <0.03 322 209 <5 0 1 20.06.01DWH -34 Md. Hosen Sheikh Aminpur UBJ - 03 TBC - 01 1999 Nov 14 7.5 <0.03 187 122 <5 0 1 20.06.01DWH -35 Imam Mirjapur Jame Mirzapur UBJ - 03 TBC - 01 1999 Nov 12 7.1 <0.03 189 189 <5 0 0 20.06.01DWH -36 Md. Motaleb Hossain

KhasAminpur UBJ - 03 TBC - 01 1999 Dec 11 7.2 <0.03 340 222 <5 0 2 20.06.01

DWH -37 Md. Chad Ali Kash Aminpur UBJ - 03 TBC - 01 1999 Nov 14 7.0 <0.03 241 157 <5 0 1 20.06.01DWH -38 Md. Akkas Ali Aminpur UBJ - 03 TBC - 01 1999 Nov 10 7.0 <0.03 342 222 <5 0 0 20.06.01DWH -39 Md. Sahabuddin

MasterRajnarayonpur

UBJ - 03 TBC - 01 1999 Nov 10 7.0 <0.03 305 198 <5 0 5 20.06.01

DWP -40 Mukul Malitha Ruppur (Malithapara

UIP - 01 TIC - 02 2003 Jan 40 7.5 <0.03 202 131 <5 0 1 25.01.03

DWP -41 Mrs.Salina Khatun Ruppur (Biswaspara

UIP - 01 TIC - 02 2003 Jan 37 7.0 <0.03 172 112 <5 0 3 25.01.03

DWP -42 Mrs.Samshunnahar Ruppur (Charabottala

UIP - 01 TIC - 02 2003 Jan 53 7.1 <0.03 198 127 <5 0 0 25.01.03

DWP -43 Mrs.Rashida Khatun Babulchara UIA - 02 TIC - 02 2003 Jan 48 7.1 <0.03 211 137 <5 0 1 25.01.03DWP -44 Md.Harunar Rashid Durgapur USA - 01 TSC - 03 2003 Jan 28 7.4 <0.03 222 144 <5 0 3 25.01.03DWP -45 Mrs.Samshunnahar Gopalpur USK - 01 TShC -

052003 Jan 20 7.0 <0.03 282 183 <5 0 2 25.01.03

DWP -46 Md.Abdul Momin Khan Sayedpur (Dangapara)

USA - 01 TSC - 03 2003 Jan 35 7.2 <0.03 298 194 <5 0 5 25.01.03

DWP -47 Md.Mojibur Rahman Ahmedpur USA - 01 TSC - 03 2003 Jan 32 7.3 <0.03 301 196 <5 0 0 25.01.03DWP -48 Md. Khorshed Alam Koromja UBK - 04 TBC - 01 2003 Jan 28 6.9 <0.03 314 204 <5 0 1 25.01.03DWP -49 Md.Mamunur Rashid Sayedpur

(Ujanpur)USA - 01 TSC - 03 2003 Jan 32 7.1 <0.03 382 248 <5 0 3 25.01.03

DWP -50 Md.Zinna Ahmedpur USA - 01 TSC - 03 2003 Jan 30 7.4 <0.03 203 132 <5 0 4 25.01.03DWP -51 Md.Azim Uddin Bhabanipur UBR - 02 TBC - 01 2003 Jan 28 7.4 <0.03 168 109 <5 0 1 25.01.03DWP -52 Md.Badsha Master Durgapur USA - 01 TSC - 03 2003 Jan 28 7.0 <0.03 321 209 <5 0 2 25.01.03DWP -53 Sree Nironjan Kumar Sagorkandi UBM - 01 TBC - 01 2003 Jan 35 7.1 <0.03 354 230 <5 0 0 25.01.03DWP -54 Md.Raton Chowdhuri Arifpur UPM - 04 TPC - 04 2003 Jan 15 7.3 <0.03 265 172 <5 0 7 25.01.03DWP-55 Md. Abdul Awal Bhabanipur UBR - 02 TBC - 01 2003 Jan 27 7.0 <0.03 312 203 <5 0 5 25.01.03DWP -56 Sree Sudha Ranjan Shagorkandi UBM - 01 TBC - 01 2003 Jan 26 7.2 <0.03 255 166 <5 0 8 25.01.03DWP -57 Md.Rabiul Islam Char Ruppur UIP - 01 TIC - 02 2004 Jan 24 7.3 <0.03 265 172 <5 0 2 28.01.04DWP -58 Md.Zahidul Haq Char Ruppur UIP - 01 TIC - 02 2004 Jan 25 7.0 <0.03 346 225 <5 0 1 28.01.04DWP -59 Md.Shahjahan Char Ruppur UIP - 01 TIC - 02 2004 Jan 25 7.3 <0.03 269 175 <5 0 4 28.01.04DWP -60 Md.Iddris Ali Arippur UPM - 04 TPC - 04 2004 Jan 39 7.0 <0.03 187 122 <5 0 2 28.01.04DWP -61 Md.Shamim Hossain Arippur UPM - 04 TPC - 04 2004 Jan 27 7.4 <0.03 340 221 <5 0 1 28.01.04DWP -62 Md.Mizanur Rahman Bishawnathp

urUBJ - 03 TBC - 01 2004 Jan 27 6.9 <0.03 241 157 <5 0 3 28.01.04

2222

DWP -63 Mrs.Shahanara Lipi Dariapur USA - 01 TSC - 03 2004 Jan 25 7.1 <0.03 305 198 <5 0 4 28.01.04DWP -64 Md.Abul Raja Birahimpur USA - 01 TSC - 03 2004 Jan 28 7.3 <0.03 202 131 <5 0 0 28.01.04DWP -65 Md.Habibur Rahman Rajnaraynpur UBJ - 03 TBC - 01 2004 Jan 24 7.2 <0.03 211 137 <5 0 0 28.01.04DWP -66 Md.Raij Shikder Bhuya Para UBR - 02 TBC - 01 2004 Jan 25 7.2 <0.03 282 183 <5 0 5 28.01.04

2323