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This is a publication by: Ramakrishna Vivekananda Mission 7, Riverside Road Barrackpore: 700 120
This report is authored by Mr. Soumyadeep Mukhopadhyay, Project Team Leader
For further information, please contact:
Soumyadeep Mukhopadhyay Project Team Leader, DM 06-0880 RKVM-IAS, 3, B.T. Road, Agarpara Kolkata: 700 058 West Bengal, INDIA Office: +91 033 2583 9580 Fax: +91 033 2563 7302 Mobile: +91 94337 16340 Email: [email protected]
In spite of all the devilry that Religion is blamed with, Religion is not at all at
fault; no Religion ever persecuted men, no Religion ever burnt witches, no
Religion ever did any of these things. What then incited people to do these
things? Politics, but never Religion. And if such Politics takes the name of
Religion, whose fault is it?
It is our privilege to be allowed to be charitable, for only so can we grow.
Let the giver kneel down and give thanks; let the receiver stand up and permit.
Be strong and stand up and seek the God of Love. This is the highest strength.
What power is higher than the power of purity? Love and purity govern the
world. This love of God cannot be reached by the weak; therefore be not weak,
either physically, mentally, morally or spiritually.
Foreword
rsenic problem in West Bengal & Bangladesh caught the attention of
the scientific community & the media alike from the early 1990s. Even
in the new millennium, the problem remains untamed to a large extent
probably due to the lack of a technology that can address this problem at its
root cause resulting in a sustained solution. The common people remain to
be the helpless sufferers. So, Ramakrishna Vivekananda Mission, having its
Head Quarters at Barrackpore, West Bengal, India was thinking of doing
something for these unfortunate people of the Nadia & North 24 Parganas
of West Bengal. There are other districts also, where this problem persists.
But RKVM has stronghold in these two districts & wanted to initiate their
work here.
Back in 2004, RKVM provided infrastructural facility to a consortium of
Indian & European Institutes at its Kasimpore centre to work upon a Pilot
project funded by European Union (TiPOT). A sustainable technology for
treating the aquifer itself for removing arsenic was experimented here. No
chemical filters were used or no toxic sludge was generated in the process.
Once it produced desirable result, the consortium took part in the
Development Marketplace Global Competition of the World Bank in 2006.
The then Honorary Registrar of RKVM-IAS, Mrs. Angana Dutta presented the
proposal to the DM authority that considered the proposal to be truly
innovative & honoured it as one of the Winners among 2,525 other
proposals submitted from all around the World. The fund was released in
five installments from July 2007 to December 2008. RKVM executed the
work by recruiting research assistants, engineers, supervisors & plumbers
especially for this project. Also, RKVM had constant interaction with the
four European advisors viz Queen’s University, Belfast, Universidad Miguel
Hernandez, Spain, Leiden University, The Netherlands & Stuttgart
University, Germany. Dr Bhaskar Sen Gupta of QUB was one of the main
guiding agents in both the TiPOT project & this World Bank project.
A
Under this particular project, RKVM has installed six Subterranean Arsenic
Removal plants – two in Nadia district & four in North 24 Parganas. All of
them are presently running very well & delivering water at their fullest
capacity. At present, RKVM is regularly supervising the plants & is running
them initially at its own cost. The scientific data show promising results.
The most important thing regarding this project is that, it works and that
too at a very low running cost.
These projects have generated great hopes among the people of these areas
& the situation demands that we undertake more of this type of work in
other needy areas of West Bengal in association with the funding agencies
who are primarily focusing in the health & environmental sectors. RKVM is
a charitable non profit organisation that has won National Award thrice for
societal causes. It has the ability and infrastructure to provide every
support & enough man power to carry on this project in its second phase
with the valuable experience it has gained from the first phase of this
extraordinary work.
RKVM takes this opportunity with great pleasure to express its high
appreciation & deep gratitude to the World Bank authority for supporting
the noble cause and to those friends who helped it to implement this project.
With grateful thanks to everybody,
Dated: 5th March, 2009
Swami Nityananda
Secretary, RKVM
Acknowledgements
e, on behalf of the Ramakrishna Vivekananda Mission will like to congratulate the
common people of the arsenic affected West Bengal on the occasion of completion of
this project. We will also like to convey our heartfelt gratitude to the World Bank
Development Marketplace for providing the RKVM a chance to serve the people who are
in distress and thus in the process helped to upheld the Mission’s motto of God Worship
in Man irrespective of class, creed, religion & colour. The DM deserves thanks for
standing beside RKVM & supporting it through thick & thin throughout the project
period.
On behalf of the project team, I will remain ever grateful to the Secretary of the Mission,
Swami Nityananda for providing every infrastructural, administrative and moral support
to the Team during the time of need. The entire Governing Body of the RKVM,
Barrackpore will need special mention for providing solid administrative support to the
project team, always complying with its requests and taking great interest in the activity
of the team.
Our heartfelt regard goes to all the Advisors and Research Scholars who devoted their
valuable time and energy towards success of this project for the benefit of the needy
common people. Our thanks goes to Dr. Bhaskar Sen Gupta from Queen’s University
Belfast, Prof Angel Carbonell Barrachina from Universidad Miguel Hernandez-Spain,
Prof Wouter de Groot from CML, Leiden University- the Netherlands and Prof Rott &
Prof Carsten Meyer from ISWA, Stuttgart University-Germany.
On this occasion, I will like to take the opportunity to acknowledge all the persons who at
some point of time or other were associated with this work, played their part effectively
and thus contributed towards the overall success of the project. Prof H. S. Ray, Mrs
Angana Dutta - the former RKVM-IAS Honorary Registrar, Ms Sreejita Ghorui and Ms
Rajanita Das Purakayastha demand special mention in this regard. I will also thank all
the persons associated with this project at this point of time, who have extended their co-
operative hand and took great pains to make this project successful. I will remain ever
grateful to Mr Sushil Bhattacharyya, the Registrar of RKVM-IAS and Mr Saral Das
W
Gupta, Member – Governing Body of RKVM without whose co-operations and interests,
it was difficult for the project team to perform their duty.
The Research Assistants Mr Indrajit Bera and Mr Krishnendu Halder, the Operators, the
Drivers, the Office Staff and the Finance Office of RKVM – all of them, through their
concerted efforts made the workplace enjoyable for all of us. Cheers to all of you guys …
working with you all was really a privilege for me. The memory of every moment we
strived together as a team will last a lifetime.
Last, but not the least, I will thank our friends and families who provided us with moral
support during the time of great work pressure & tough deadlines, keeping us fit enough
to rise to the challenge and shoulder our responsibilities.
Thank you all for your co-operation, support and patience,
Dated: 6th March, 2009
Soumyadeep Mukhopadhyay
Project Team Leader
DM 06-880
C O N T E N T S
Summary and Report Structure
1
1. Introduction
1.1 Project Background: TiPOT Project at Kasimpore
1.2 Arsenic: Some Background Information
1.3 Previous Research on Arsenic & it’s Mitigation
1.4 Objectives of the Project
1.5 Organizational Structure
3
3
4
8
10
11
2. Principle: Science & Technology behind the SAR system
12
3. Relevance of SAR in the Study Area
3.1 Arsenic in groundwater of West Bengal
3.2 The arsenic problem of drinking water
3.3 The arsenic problem of irrigation water
3.4 The arsenic problem in local perceptions
3.5 The arsenic problem in GO perceptions
3.6 Solutions for drinking water proposed and applied
3.7 Solutions for drinking water applied in West Bengal
3.8 Solutions for irrigation water proposed and applied
16
16
18
19
21
22
22
32
34
4. The Plant Design
4.1 Design criteria
4.2 Options available: Variants
4.3 Line Diagram of SAR Plant
35
35
37
40
5. Providing the SAR Utility
5.1 Selection Criteria of the Project Sites
5.2 Survey Methods
5.3 Arsenic & Iron levels in the aquifers of the Project Sites
5.4 Installing the Plants
5.5 Starting the Operation and Data Generation
5.6 Delivering Water & Quality Monitoring
5.7 Realising Problems & Prospects
41
41
47
53
54
54
55
56
6. Elements of the Delivery System of SAR
6.1 Introduction to Delivery System
6.2 What is supplied?
6.3 Users, Suppliers and ‘Central Actor’
6.4 The relationship between Central Actor & Users
6.5 The relationship between Central Actor & Suppliers
6.6 Facilitators
59
59
60
62
63
65
65
7. Operation & Maintenance Issues
7.1 Operation
7.2 Maintenance
7.3 Certification
7.4 Delivery System
69
69
70
70
71
8. Results
8.1 Data generated during Operation
8.2 Discussion
72
73
79
9. Conclusions & Recommendations
80
10. Photographs
83
11. Annexure
I. Manuals & Questionnaires
II. Agreements, Certificate & Technology Transfer letter, etc
III. Persons associated with DM 06-880
92
93
105
113
12. References
114
Contact Information 117
Summary and Report Structure
he present report focuses on the implementation of the project “Subterranean
Arsenic Removal: Experiment to Delivery” (DM 06-0880) by Ramakrishna
Vivekananda Mission, Barrackpore with funding from the World Bank Development
Marketplace and technical help from Queen’s University- Belfast (QUB), ISWA-Stuttgart
University Germany, University of Leiden - The Netherlands (CML) and Universidad Miguel
Hernandez – Spain (UMH).
As the title indicates, this project is the field application of the experiment done on
Subterranean Arsenic Removal (SAR) System from 2004 to 2006 at Kasimpore, North 24
Parganas, West Bengal under the TiPOT project that was funded in the Asia Pro Eco
Programme of the EU (Contract reference no.: ASI/B7-301/2598/24-2004/79013). The
objectives of the project were the development of a low-cost technology for in-situ
treatment of groundwater for potable and irrigation purposes and to formulate practice-
based guidelines for a rural water treatment technology in Eastern India.
Based on the findings of that TiPOT project, RKVM along with the partners QUB, CML,
UMH & ISWA participated in the “Development Marketplace Global Competition, 2006”
with a project proposal titled “Subterranean Arsenic Removal: Experiment to Delivery” and
came out Winner in the theme area of “Innovations in Water, Sanitation and Energy
Services to the Poor People”.
Under this project (code: DM 06-0880), RKVM had to install 6 in-situ arsenic treatment
plants based on the SAR technology. Dr. Bhaskar Sen Gupta from QUB was the Chief
Advisor, Prof Wouter de Groot from CML was the advisor on the Delivery System, prof
Angel carbonell barrachina from UMH was the Food Safety advisor and Prof Rott & Prof
Carsten Meyer from ISWA advised on the Technical aspects.
This report is divided into twelve sections. The first section introduces the reader with a
few basic aspects viz the origin of the project (1.1), some facts about arsenic (1.2), the
extent of research done till date on arsenic removal technologies (1.3), the primary &
secondary objectives of the project (1.4) and the organizational structure sustained by
the RKVM to implement this project (1.5).
The second section deals with the principle behind the SAR technique. The probable
mechanism of arresting of arsenic in the aquifer is discussed here with diagrams &
schematic diagrams.
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The third section discusses the relevance of applying the SAR technology in the particular
study area. It explores the scenario of arsenic in groundwater of West Bengal (3.1), the
arsenic problem specifically in drinking water (3.2) and in irrigation water (3.3). It also
brings out a discussion on the extent of local (3.4) and governmental (3.5) perception of
the problem. Then it ventures into the solution part of the problem i.e. the solutions
proposed & applied for drinking water in general (3.6), particularly in West Bengal (3.7)
and for irrigation water (3.8).
The fourth section elucidates on the design of the plant. The design criteria kept in the
mind is discussed in sub section 4.1. From the TiPOT project, three options were
available for installations (4.2). Among these, T-6000l is being selected for installation.
The fifth section gives an insight into the implementation stage of the project. The
aspects kept into consideration while selecting the sites are mentioned in the sub section
5.1. The methods of socio-economic survey, WTP survey & food-safety survey are also
discussed (5.2). The questionnaires are provided at the annexure. Lastly, the arsenic &
iron concentrations initially at the selected project sites are tabulated (5.3). The
installation phase (5.4), the start-up phase (5.5), the quality monitoring phase (5.6) and
problem rectification phase (5.7) are all dealt with in this section.
In the sixth section, the reader gets introduced to the concept of delivery system and
various terms related with the subject (6.1, 6.2 and 6.3). The relationships between
different agents of the supply chain have been mentioned in sub sections 6.4, 6.5 and
6.6.
The seventh section then brings us into the Operation & maintenance issues of the T-
6000L model installed at the project sites. In various sub sections 7.1, 7.2, 7.3 & 7.4, the
issues of operation, maintenance, certification & delivery system are discussed.
The eighth section reveals the result that the project team obtained while water quality
monitoring of the plant water. The graphs generated from the data are provided here &
an observer will be mesmerized to see the synchronization between the variation of
arsenic & iron in the aquifer water as the plant operation continued (8.1). The findings
are discussed in detail (8.2).
Finally, we reach a conclusion and recommend some aspects that will help in smooth
running of the plants as well as reduce the arsenic ingestion by the common people at
section 9. Section ten shows some photographs of the project and section eleven and
twelve provides annexure & references for the avid readers.
Subterranean Arsenic Removal: Experiment to Delivery
Ramakrishna Vivekananda Mission - Institute of Advanced Studies 3
1
Introduction 1.1 Project Background: TiPOT Project at Kasimpore
1.2 Arsenic: Some Background Information
1.3 Research History
1.4 Objectives of the Project
1.5 Organizational Structure
AR means ‘Subterranean Arsenic Removal’. This is a technology that works to keep
the arsenic in the ground before it might move into the drinking water or irrigation
water supply wells and pipes. Another term denoting the same idea is ‘In-Situ
Groundwater Treatment’. In all parts in the report when we speak about SAR in specific
terms, e.g. on cost or performance, we specifically refer to SAR of the type developed by
ISWA, Germany, because that technology is the core of both the experimental TiPOT
project as well as the World Bank Project DM06-880. What this SAR does is to build up
adsorption capacity in the soil, so that the arsenic gets stuck there before reaching the
well.
1.1 Project Background: TiPOT Project at Kasimpore
he TiPOT Project at Kasimpore was the fore runner of the World Bank Project DM 06-
880. The consortium of some European Universities & Indian Research Institutes
experimented with the In-situ Arsenic Removal Technology at Kasimpore under the
S
T
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funding of EU. After obtaining desired result, they decided to take their work to the next
level by participating in the DM 2006 Competition of the World Bank.
The TiPOT (Technology for in-situ treatment of groundwater for potable and irrigation
purposes) project at Kasimpore on "Subterranean Arsenic Removal" was funded in the
Asia Pro Eco Programme of the EU (Contract Reference No.: ASI/B7-301/2598/24-
2004/79013). The objectives of the project were the development of a low-cost
technology for in-situ treatment of groundwater for potable and irrigation purposes and
to formulate practice-based guidelines for this a rural water treatment technology for
Eastern India. Roughly, 70 million people in the Bengal delta region are affected due to
arsenic exposure especially through consumption of drinking water. The aims of the
project were therefore the assurance of arsenic free water for general consumption and
irrigation at low cost and to enhance food safety in the affected areas through
sustainable irrigation and farming practices.
A Consortium of Universities and Institutes worked together on the project. The lead
partner was Queens University Belfast (QUB). Other participating partners were: National
Metallurgical Laboratory, Jamshedpur, India (NML); Institute for Sanitary Engineering,
Water Quality and Solid Waste Management, Stuttgart, Germany (ISWA); Universidad
Miguel Hernandez, Alicante, Spain (UMH); Institute of Environmental Management and
Studies, India (IEMS), and the Institute of Environmental Sciences, Leiden University, the
Netherlands (CML).
Having a successful history in countries as Germany and Switzerland, ISWA (with help of
especially NML and RKVM-IAS), applied the in-situ technology in a case study site near
Kolkata at Kasimpore. In anticipation of the positive results, other partners worked on
issues as arsenic in food (UMH), arsenic and irrigation (QUB) and the way to bring the
technology to the people in India (CML and IEMS).
After the successful outcome in the TiPOT project, RKVM-IAS competed for the
"Development Marketplace Global Competition, 2006" hosted by the World Bank in the
"Water & Sanitation for the Poor People" category & emerged as one of the Winners
among 2,525 competitors in this prestigious competition.
1.2 Arsenic: Some Background Information
lemental arsenic (As) is a member of Group 15 of the periodic table, with nitrogen,
phosphorus, antimony and bismuth. It has an atomic number of 33 and an atomic
mass of 74.91. The Chemical Abstract Service (CAS), National Institute for Occupational
Safety and Health Registry of Toxic Effects of Chemicals (RTECS), Hazardous Substances
E
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Data Bank (HSDB), European Commission, and UN transport class numbers are 7440-38-
2, HSB 509, CG 05235 000, 033-001-00-X and UN 1558, respectively.
Arsenic is a metalloid widely distributed in the earth’s crust and present at an average
concentration of 2 mg/kg. It occurs in trace quantities in all rock, soil, water and air.
Arsenic can exist in four valence states: –3, 0, +3 and +5. Under reducing conditions,
arsenite (As (III)) is the dominant form; arsenate (As (V)) is generally the stable form in
oxygenated environments. Elemental arsenic is not soluble in water. Arsenic salts exhibit
a wide range of solubilities depending on pH and the ionic environment.
Sources and occurrence of arsenic in the environment
Arsenic is present in more than 200 mineral species, the most common of which is
arsenopyrite. It has been estimated that about one-third of the atmospheric flux of arsenic is
of natural origin. Volcanic action is the most important natural source of arsenic, followed by
low-temperature volatilization. Inorganic arsenic of geological origin is found in
groundwater used as drinking-water in several parts of the world, for example Bangladesh.
Organic arsenic compounds such as arsenobetaine, arsenocholine, tetramethylarsonium
salts, arsenosugars and arsenic-containing lipids are mainly found in marine organisms
although some of these compounds have also been found in terrestrial species. Elemental
arsenic is produced by reduction of arsenic trioxide (As2O3) with charcoal. As2O3 is produced
as a by-product of metal smelting operations. It has been estimated that 70% of the world
arsenic production is used in timber treatment as copper chrome arsenate (CCA), 22% in
agricultural chemicals, and the remainder in glass, pharmaceuticals and non-ferrous alloys.
Mining, smelting of non-ferrous metals and burning of fossil fuels are the major industrial
processes that contribute to anthropogenic arsenic contamination of air, water and soil.
Historically, use of arsenic-containing pesticides has left large tracts of agricultural land
contaminated. The use of arsenic in the preservation of timber has also led to contamination
of the environment.
Environmental transport and distribution
Arsenic is emitted into the atmosphere by high-temperature processes such as coal-fired
power generation plants, burning vegetation and volcanism. Natural low-temperature
biomethylation and reduction to arsines also releases arsenic into the atmosphere. Arsenic
is released into the atmosphere primarily as As2O3 and exists mainly adsorbed on
particulate matter. These particles are dispersed by the wind and are returned to the earth
by wet or dry deposition. Arsines released from microbial sources in soils or sediments
undergo oxidation in the air, reconverting the arsenic to non-volatile forms, which settle
back to the ground. Dissolved forms of arsenic in the water column include arsenate,
arsenite, methylarsonic acid (MMA) and dimethylarsinic acid (DMA). In well-oxygenated
water and sediments, nearly all arsenic is present in the thermodynamically more stable
Subterranean Arsenic Removal: Experiment to Delivery
Ramakrishna Vivekananda Mission - Institute of Advanced Studies 6
pentavalent state (arsenate). Some arsenite and arsenate species can interchange oxidation
state depending on redox potential (Eh), pH and biological processes. Some arsenic species
have an affinity for clay mineral
surfaces and organic matter and
this can affect their environmental
behaviour. There is potential for
arsenic release when there is
fluctuation in Eh, pH, soluble
arsenic concentration and sediment
organic content. Weathered rock
and soil may be transported by wind
or water erosion. Many arsenic
compounds tend to adsorb to soils,
and leaching usually results in
transportation over only short
distances in soil.
Three major modes of arsenic
biotransformation have been found
to occur in the environment: redox
transformation between arsenite
and arsenate, the reduction and
methylation of arsenic, and the biosynthesis of organoarsenic compounds. There is
biogeochemical cycling of compounds formed from these processes.
Under oxidizing and aerated conditions, the predominant form of arsenic in water and soil
is arsenate. Under reducing and waterlogged conditions (< 200 mV), arsenites should be
the predominant arsenic compounds. The rate of conversion is dependent on the Eh and pH
of the soil as well as on other physical, chemical and biological factors.
In brief, at moderate or high Eh, arsenic can be stabilized as a series of pentavalent
(arsenate) oxyanions, H3AsO4, H2AsO4–, HAsO4
2– and AsO43–. However, under most reducing
(acid and mildly alkaline) conditions, arsenite predominates. A pH and Eh diagram is shown
in Fig. 2.
Human exposure through food & water
Non-occupational human exposure to arsenic in the environment is primarily through the
ingestion of food and water. Of these, food is generally the principal contributor to the daily
intake of total arsenic. In some areas arsenic in drinking-water is a significant source of
exposure to inorganic arsenic. In these cases, arsenic in drinking-water often constitutes the
principal contributor to the daily arsenic intake. The daily intake of total arsenic from food
Subterranean Arsenic Removal: Experiment to Delivery
Ramakrishna Vivekananda Mission - Institute of Advanced Studies 7
and beverages is generally between 20 and 300 µg/day. Limited data indicate that
approximately 25% of the arsenic present in food is inorganic, but this depends highly on
the type of food ingested. Inorganic arsenic levels in fish and shellfish are low (< 1%).
Foodstuffs such as meat, poultry, dairy products and cereals have higher levels of inorganic
arsenic. Pulmonary exposure may contribute up to approximately 10 µg/day in a smoker and
about 1 µg/day in a non-smoker, and more in polluted areas. The concentration of
metabolites of inorganic arsenic in urine (inorganic arsenic, MMA and DMA) reflects the
absorbed dose of inorganic arsenic on an individual level. Generally, it ranges from 5 to 20
µg As/litre, but may even exceed 1000 µg/litre.
Long term effects on human health
Long-term exposure to arsenic in drinking-water is usually related to increased risks of
cancer in the skin, lungs, bladder and kidney, as well as other skin changes such as
hyperkeratosis and pigmentation changes. These effects have been demonstrated in many
studies using different study designs. Exposure–response relationships and high risks have
been observed for each of these end-points. Increased risks of lung and bladder cancer and
of arsenic-associated skin lesions have been reported to be associated with ingestion of
drinking-water at concentrations 50 µg arsenic/litre. Precursors of skin cancer have been
associated with drinking-water arsenic levels < 50 µg/litre. Arsenic is considered to be
genotoxic in humans on the basis of clastogenicity in exposed individuals and findings in
vitro.
Arsenic exposure via drinking-water induces PVD. Whether arsenic alone is sufficient to
cause the extreme form of this disease, BFD, is not known. Conclusions on the causality of
the relationship between arsenic exposure and other health effects are less clear-cut. The
evidence is strongest for hypertension and CVD, suggestive for diabetes and reproductive
effects and weak for cerebrovascular disease, long-term neurological effects and cancer at
sites other than lung, bladder, kidney and skin.
Effects on other organisms in the environment
Aquatic and terrestrial biota shows a wide range of sensitivities to different arsenic species.
Their sensitivity is modified by biological and abiotic factors. In general, inorganic arsenicals
are more toxic than organoarsenicals and arsenite is more toxic than arsenate. The mode of
toxicity and mechanism of uptake of arsenate by organisms differ considerably.
Arsenic compounds cause acute and chronic effects in individuals, populations and
communities at concentrations ranging from a few micrograms to milligrams per litre,
depending on species, time of exposure and end-points measured. These effects include
lethality, inhibition of growth, photosynthesis and reproduction, and behavioural effects.
Arsenic-contaminated environments are characterized by limited species abundance and
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Ramakrishna Vivekananda Mission - Institute of Advanced Studies 8
diversity. If levels of arsenate are high enough, only species which exhibit resistance may be
present.
1.3 Previous Research on Arsenic & its mitigation:
here is an enormous amount of publications on the arsenic contamination problem in
West Bengal, India and Bangladesh. The site www.engconsult.com/arsenic/refs.htm, for
instance, gives a reference list of 139 papers related to arsenic. There is the arsenic info
crisis centre on line (http://bicn.com/acic/) that includes an info-bank of news articles,
scientific papers, comprehensive links to other relevant sites, online forum, email newsletter,
and local site search. There is also the www.sos-arsenic.net where several links can be found
to topics related to arsenic pollution and project combating the problem in West Bengal and
Bangladesh. There is a very good report from the World Bank (2005) that deals not only with
the arsenic problem but that also extensively describes proposed and applied technologies
and alternatives.
Source substitution is often considered more appropriate than arsenic removal from the host
water (Ahmed, 2003). However, the use of alternative sources requires a major technological
shift from easily available groundwater supply to some other resources like surface water or
blending of multiple water resources etc. It calls for a big capital investment, which may not
be economically feasible always. On the other hand, the treatment of arsenic contaminated
water for the removal of arsenic to an acceptable level is one of the safe options for
dependable water supply (Ahmed, 2003). Since the detection of arsenic in groundwater, a lot
of effort has been mobilized for treatment of arsenic-contaminated water to make it safe for
drinking. During the last few years, many arsenic detection and test methods and small-
scale arsenic removal technologies have been developed, field-tested, and used under
different programs in developing countries. While considering the appropriateness of the
water supply technology for arsenic mitigation particularly in rural area, following factors are
considered to be important for selection.
1) Avoidance or substantial and consistent reduction of the arsenic in the final product
2) Low capital cost as well as running cost
3) Water quality and quantity
4) Robustness of the process
5) Operational ease, hazard and safety
6) Environmental soundness
7) Socio economic considerations
8) Convenience and social acceptability
9) Feasibility
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Based on the above criteria, a review of different mitigation technologies for arsenic removal
from the contaminated groundwater is done. There are several methods available for
removal of arsenic from water. The most commonly used processes of arsenic removal from
water have been described by Cheng et al. (1994), Hering et al. (1996, 1997), Kartinen and
Martin (1995), Shen (1973) and Joshi and Chaudhuri (1996) etc. A detailed review of arsenic
removal technologies have been presented by Sorg and Logsdon (1978). Several advances in
arsenic removal technologies have been developed by Jokel (1994). In view of the lowering of
the standard of WHO for the maximum permissible levels of arsenic in drinking water, a
review of arsenic removal technologies was carried out to consider the economic factors
involved in implementing more stringent drinking water standards for arsenic (Chen and
others 1999). Many of the arsenic removal technologies have been discussed in details in the
AWWA (American Water Works Association) reference book (Pontius 1990). Murcott (2000)
has compiled a review of low-cost well water treatment technologies for arsenic removal,
with a list of companies and organizations involved in arsenic removal technologies.
Comprehensive reviews of arsenic removal processes have been documented by Ahmed, Ali
and Adeel (2001), Johnston (2000), Heijnen, and Wurzel (2000), and Ahmed (2003). The
AWWA conducted a comprehensive study on arsenic remedial options and evaluation of
residuals management issues (AWWA 1999).
The Bengal delta is one of the most fertile places in the world, replenished each year by the
mighty flood water of the monsoon season with nutritious sediments. The Green Revolution
in India transformed the agriculture in intensive, expanding production from one to four
crops per year, due mainly to the enormous population growth. As a consequence of both
intensive agriculture and population growth, these areas are mostly groundwater dependent
and in those areas environmental conditions are optimum to release As to groundwater by
oxidation of pyrite, reduction of ferric iron hydroxides to ferrous iron or by over-application
of phosphate fertilizer to surface soils. In addition, the dependence of the West Bengal
population on groundwater is also because surface water is heavily contaminated with
microorganisms and has been the cause of millions of deaths each year through water-borne
disease while ground water is free of microorganism.
In West Bengal it is reported that about 6 million people from 2600 villages in 74
arsenic-affected blocks are at risk and for instance 9.8% of 86,000 people examined are
suffering arsenic damages.
Nickson et al. tested As concentration in 132,262 government installed hand pumps in 8
districts and overall 25.5% of samples were found to contain As at concentrations greater
than 50 Sg As L-1 and 57.9% at concentration greater than 10 Sg As L-1. Arsenic
contaminated groundwater is not just used for drinking water but is also widely used for
irrigation of crops, and particularly for the staple food paddy rice (Oryza sativa), which
represents a great portion of caloric intake for the Indian rural population. If arsenic levels
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build up in paddy soils, it can lead to elevated As in rice grain, and the amount of As
ingested by inhabitants of this region could be considerably more than previously thought.
The studies carried out by Roychowdhury et al. in the Murshidabad district (West Bengal)
provided data for t-As intake from water and from foodstuff. It was estimated at 4.5 times
greater than the Tolerable Daily Intake (TDI) and contributions from foodstuff (rice,
vegetables, and spices) represented 27% of the daily t-As intake. As a consequence of long
periods of exposure to such high level of As intake people suffer from damage to the skin,
kidney, brain, heart and circulation; miscarriages and stillbirth also seem to increase
although bladder and lung cancer are the major killers. Besides, social problems arise from
As-related diseases. For example, marriages are annulled and people with arsenicosis are
avoided. In some areas, panic sets in. With so many likely to fall ill, a huge burden has been
placed on family units, and their land.
Summarizing, in the As-affected parts of India the main sources of As in the diet are 1)
drinking water from tube wells and 2) foodstuff such as cooked rice and vegetables and both
have given rise to high As daily intake resulting in serious health diseases and social
problems.
1.4 Objectives of the Project
1.4.1. Overall Developmental Objectives:
• Study of demand of safe drinking water in Arsenic prone villages and assessment
of benefits/ willingness to pay.
• Implementation of the low cost technology to remove arsenic and iron from the
groundwater.
• Provide some recommendations about improvement in Agricultural and Farming
practices to reduce arsenic contamination in food chain and to assess the
suitability of this technique to provide water for irrigation purposes.
• Insurance on the acceptability of the technology by beneficiaries, Local Self Govt.
agencies, Self help Groups, and other NGOs.
• Assessment on the replication of the technology in neighboring countries like
Bangladesh, in terms of the cost-benefit ratio, the socio-economic conditions and
the physiographic factors.
• Data generation about the performance of the plants and to monitor the water
quality.
1.4.2. Intermediate Objectives:
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• Creating awareness among the local rural people about the severity of arsenic
problem and about the intended project for their full co-operation.
• Provision of arsenic & iron free safe drinking water to the extreme rural belts of
West Bengal where arsenic contamination of groundwater is a major problem.
• Distribution of drinking water at a cost affordable by the poor people.
• Income generation for the household operator/Central Actor, in charge of the
pump & the maintenance of the project by selling the arsenic free drinking water
at a minimum charge.
1.5 Organizational Structure
he Ramakrishna Vivekananda Mission came up with this organizational structure for
implementing this particular project.
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2
Principle: Science & Technology behind the SAR System
n the in-situ treatment method, the aerated tube well water is stored in feed water
tanks and released back into the aquifers through the tube well by opening a valve in
a pipe connecting the water tank to the tube well pipe under the pump head (Figure
1). Because there is little or no oxidant in the deep soil pores and the permeability of the
soil layers are usually low, there is a strong driving force for the oxidant to diffuse into
these locations and oxidize the contamination. The dissolved oxygen in aerated water
oxidizes arsenite to less-mobile arsenate, the ferrous iron to ferric iron and Manganese
(II) to Manganese (III), followed by adsorption of arsenate on Fe (III) and manganese (III)
and subsequent precipitation resulting in a reduction of the arsenic content in tube well
water. Oxidation is further enhanced biologically by bacteria living in the subsurface and
is termed bioremediation process. In-situ oxidation process can work in tandem with
bioremediation by chemically oxidizing recalcitrant compounds and creating products
that are readily biodegradable.
The process of in-situ oxidation of groundwater virtually transfers the oxidation and
filtration process of the conventional above ground water treatment plants into the
aquifer. The underground aquifer is used as a natural biochemical reactor. A part of the
delivered groundwater is re-circulated back into the aquifer carrying oxidising agent,
generally atmospheric oxygen. Oxygen can be introduced into water by aerating it and
then recharging the water into the aquifer.
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The basic configuration for subterranean processing consists of an oxidation station,
either a spray nozzle or water jet air pump, a storage tank and pipelines for delivery from
the aquifer and for enrichment (recharge) into the aquifer. The schematic arrangement is
shown in Figure 1. The water is pumped from the groundwater by means of a
submersible pump fitted within the well, aerated in the aeration chamber by means of
spray nozzles fitted inside the tank and the water is stored in a feed water tank. The
oxygen rich water is then re-infiltrated into the aquifer using the filter pipes of the
delivery system. The ratio of the delivered volume to the recharged water volume is
termed as 'efficiency coefficient' and is varied between 2 and 12 as per the requirement
depending on raw water quality and the aquifer characteristics.
Figure 1: Scheme of in
situ treatment for
arsenic removal from
Ground water
Figure 2: Oxidation zone
created in the aquifer
Because of the input of
oxygen, the redox potential
of the water is increased. A
number of different physical,
chemical and biological
processes are intensified in
the surrounding area of the
well screen section, the so
called oxidation zone (Figure
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2). The alternate operation of the wells for delivering groundwater in the tank top and
infiltration of the oxygen rich water into the aquifer induces alternating oxidation and
adsorption periods on the surface of the solid material in the aquifer.
During the groundwater delivery period (discharge) Fe (II), Mn (II) and As (III) are adsorbed
to the surface of the soil grain, which are partially coated by previously deposited
oxidation products of the previous cycle of the operation and bacteria. In the following
recharge period, the bivalent ions are oxidized to insoluble ferric hydroxides and
manganese oxides (Mn (III)) by the oxygen transported with the infiltration water into the
pores of the aquifer and get precipitated and separated from water. As (III) first oxidizes
to As(V) and then gets adsorbed on iron hydroxide and manganese hydroxide. Figure 3
illustrates the adsorption and oxidation process in the aquifer. The oxidation processes
are accelerated by autocatalytic effects of the oxidation products and by autotrophic
micro-organisms utilizing energy from the oxidation process. Additionally, the dissolved
iron and manganese are adsorbed on the bacteria sheaths by the bio-film.
The in situ method is a very cost effective and eco-friendly process for arsenic removal.
The greatest advantage of this process is there is no need for sludge handling. The
arsenic which is trapped into the sand along with the iron flocs constitute a infinitesimal
volume of the total volume being handled and hence pose very little environmental threat
in its precipitated form. The whole mass remains down below unlike other processes
where there is extra cost of sludge handling and messy disposal problem. The process is
chemical free, simple and easy to handle. There is no restriction to the volume it can
Figure 3: Oxidation – Adsorption process in the underground aquifer
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handle as long as proper time is allowed for the oxygen rich impregnated water to create
the adequate oxidizing zone in the deep aquifer. It is also quite flexible with respect to
the raw water quality as the efficient coefficient could be varied depending on the quality
of the raw water. It involves low capital cost and minimum operating cost. The results
obtained in the test site is quite promising as the process is able to reduce the arsenic
content from 100-250 Qg/l (0.1 – 0.25 mg/lt) to permissible limit of 10 Qg/l (0.01 mg/lt)
. It is ideal for a rural set up where people really cannot afford to pay a substantial
amount for water supply. The only disadvantage is that it takes some time for the whole
system to destabilize because of the slow kinetics of the oxidation process. However,
once stabilized, it remains steady for years to come.
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3
Relevance of SAR in the Study Area
3.1 Arsenic in groundwater of West Bengal
3.2 The arsenic problem of drinking water
3.3 The arsenic problem of irrigation water
3.4 The arsenic problem in local perceptions
3.5 The arsenic problem in GO perceptions
3.6 Solutions for drinking water proposed and applied
3.7 Solutions for drinking water applied in West Bengal
3.8 Solutions for irrigation water proposed and applied
his section explores the demand side of the SAR technology. We will first discuss
the existence of arsenic in groundwater in West Bengal. Then, in sub sections 3.2
and 3.3, we continue with the arsenic problem in drinking water followed by the
arsenic problem in irrigation water. We continue with the local perceptions of the arsenic
problem, followed by the arsenic problem in GO perceptions in sub sections 3.4 and 3.5
respectively. An overview of all solutions for drinking water is given according to source,
in situ treatment and post treatment of arsenic rich water in section 3.6. We continue the
chapter with the solutions for drinking water that have been applied (and failed) in West
Bengal (sub section 3.7). The chapter is rounded off by a discussion on irrigation water.
3.1 Arsenic in groundwater of West Bengal
n West Bengal most drinking water used to be collected from open dug wells and
ponds without an arsenic problem. However, due to pollution, this water became
T
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contaminated with diseases such as diarrhea, dysentery, typhoid, cholera and hepatitis.
Since the 1970s and 1980s shallow hand-pump wells (at depths less than 70 meters)
were established to provide clean drinking water that helped to control these diseases.
Arsenic was found in the waters of West Bengal in the 1980s. An estimated 30 million
people in the Ganges delta are drinking well water contaminated with arsenic (New
Scientist, 2004). Of these people, more than 6 million live in West Bengal, India
(Chakraborti, 2002).
In West Bengal, the contaminated aquifers in the region are mainly Holocene alluvial and
deltaic sediments, which form the western margins of the Bengal basin (World Bank,
2005). The five worst
affected districts of
West Bengal are Malda,
Murshidabad, Nadia, 24
North Parganas, and 24
South Parganas (ibid.).
These cover an area of
about 23,000 km2
where arsenic
concentrations found
range between 1 and
3,200 µg per litre. The
Quaternary
sedimentation patterns
vary significantly
laterally, but sands
generally predominate
to a depth of 150–200
m in Nadia and Murshidabad, while the proportion of clay increases southwards into 24
North and South Parganas, as does the thickness of surface clay (World Bank, 2005). A
shallow "first aquifer" has been described at 12–15 m depth, with an intermediate
"second aquifer" at 35–46 m, and a deep "third aquifer" at around 70–90 m depth (World
Bank, 2005). High levels of As in groundwater are especially found in the second aquifer.
CGWB (1999, as cited in World Bank, 2005) noted that the depths of arsenic-rich
groundwater vary in the different districts but where high-arsenic groundwater exists,
they are generally in the depth range of 10–80 m. Low levels of As are found in the
groundwater from the first aquifer and the third aquifer, usually. For shallow water from
the first aquifer one reason for the low As amount when actually drunk is that the water
is harvested through open dug wells that are likely to contain groundwater that is
oxidized. Groundwater from the deep aquifer also have low arsenic concentrations,
except where only a thin clay layer separates it from the overlying aquifer, allowing some
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hydraulic connection between them (World Bank, 2005). Figure 1 gives a visual
representation.
Arsenic scenario in West Bengal
Physical Parameters with respect to West Bengal
Area in sq. km 89,193
Population in million (according to 2001 Census) 80
Total number of districts 18
Number of arsenic affected districts where groundwater contains arsenic above 50 µg/L 9
Number of arsenic affected Blocks 85
Total number of water samples analyzed 1,28,303
% of samples having arsenic above 10 µg/L 50.0
% of samples having arsenic above 50 µg/L 26.7
Number of arsenic affected villages (approx.) where groundwater contains arsenic above 50
µg/L 3285
Total number of biological (hair, nail, urine, skin-scales) samples analyzed 28,000
% of samples having arsenic above normal level (average) in biological samples 85
Total people screened by medical team of SOES-JU 95,000
Number of registered arsenicosis patients 10,000
Area of arsenic affected districts in sq. km 38,865
Population of arsenic affected districts in million 42.7
Expected people drinking arsenic contaminated water in 9 affected districts above WHO
recommended value (10 µg/L) 8.7 million
Expected people drinking arsenic contaminated water in 9 affected districts above WHO
maximum permissible limit (50 µg/L) 6.5 million
People may be affected from arsenical skin lesions * 300,000
*on the basis of no. of tube wells having arsenic >300 µg/L
3.2 The arsenic problem of Drinking water
rsenic pollution is a severe problem leading to a wide variety of diseases, such as
skin lesions, blackfoot disease, diabetes, hypertension, skin cancers, and internal
cancers (lung, bladder and kidney) (World Bank, 2005). Chakraborti et al. (2002) describe
in detail the epidemiological diseases that they encountered in the As affected villages
that they studied in West Bengal and Bangladesh. A total of about 30 million people in
the Ganges delta, of which more than 6 million live in West Bengal, drink water with
arsenic concentrations higher than 50 µg per litre and are thus at risk, and more than
300 000 people may have visible arsenical skin lesions (Chakraborti, 2002). (Worldwide,
arsenic contamination from groundwater is found in China, Taiwan, Cambodia, Lao
People Democratic Republic, Pakistan, Myanmar, Vietnam, and Nepal).
In 1995, the WHO lowered the guideline value from 50 to 10 µg per litre. The Indian
standard value is still 50 Qg per litre.
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3.3 The arsenic problem of Irrigation water
egarding arsenic concentration in irrigation water, neither international agencies nor
individual countries propose any recommended maximum permissible values (World
Bank, 2005).
The arsenic problem of irrigation water concerns two issues. The first is that withdrawal
of irrigation water spoils the deep wells used for drinking water. The second concerns
arsenic ingestion through the food chain. There is not that much literature on the issue
of arsenic poisoning via crops through irrigation. In this section we first give a small
overview of the history of irrigation water in West Bengal and its sustainability. Then, we
deal with some topics that are of importance to figure out to what extent it is desirable to
go into more detail on possible solutions of contaminated irrigation water. These topics
concern: (1) standards for As concentration in the food and the extent to which As rich
irrigation water contributes to the problem, (2) the tolerable amount of arsenic in
irrigation water for which crops, and other water quality requirements (related to the
option of surface water as a solution), and (3) preconditions for solutions.
Irrigation on drinking water wells and its possible impact
In the 1960s and 1970s, agriculture in West Bengal was still rain-dependent and each
year there was only one crop following the monsoon (Roychowdhury et al., 2002). There
was thus no arsenic problem at all. To meet the food demand of the increasing
population, four to five crops in one year are common at present. To reach this end
ground water is used for irrigation (ibid.). The status of aquifer exploitation is as high as
79.40% from a single district North 24-Parganas (taken from Roychowdhury et al., 2002,
that cite Directorate of Agricultural Engineering). This heavy withdrawal of groundwater
may be the reason why iron pyrites decomposes and releases arsenic in water. Also
Johnston et al. (2001) describe the risk of unsustainability of the supply of arsenic free
water (especially relevant when large amounts of water are used). Within the same
localities, there can be a big difference between the arsenic concentrations in the ground.
In some cases, the arsenic-rich and arsenic-free zones may be separated by low-
permeability materials such as clays. In other cases however, the arsenic-rich zones may
be in hydraulic connection with arsenic-free zones. By pumping water from arsenic-free
zones, arsenic-rich water may be induced to flow into previously uncontaminated strata,
and eventually may reach the well. In the same vein, Chakraborti et al. (2002) state that:
“Rapid depletion of deep aquifers results in a deleterious influx from the As
contaminated aquifer above. Intensive efforts to provide deeper tube-wells for supplying
drinking water may be counterproductive if the aquifer is simultaneously depleted by
irrigation demands. The thoughtless exploitation of groundwater for irrigation without
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effective watershed management, which would have involved, for example, harnessing
huge surface water and rainwater resources is now seen in retrospect as a terrible
mistake.”
Standards for As in food
Concerning the issue of the possible arsenic impacts through the food chain, we first
look at As standards in food. There is no standard maximum level of arsenic in food in
South and East Asian countries (World Bank, 2005), but there are some other standards.
For instance, the provisional tolerable daily intake value of inorganic arsenic according to
FAO/WHO (1989) is 2.1 Qg/kg body weight. The WHO (1981) states that intake of
inorganic arsenic of 1.0 mg per day may give rise to skin diseases within a few years (for
a person of 50 kg this amounts to 20 Qg/kg of body weight). The UK declared a statutory
limit of 1 Qg/kg fresh weight in foods for sale in the UK (Arsenic in Food Regulations,
1959, cited in Warren et al., 2003). This leaves a safety factor of 50 compared to the
FAO/WHO norm if we assume a body weight of 50 kg and a food intake of 2.1 kg per
person per day.
Addressing the As contaminated irrigation water, the question is raised to what extent
the food contributes to the arsenic contamination. Several studies showed that most of
the arsenic enters the food chain by cooking vegetables and rice with arsenic polluted
water. Bae et al. (2002) for instance proposes that the content of arsenic in cooked rice is
higher than that in raw rice and absorbed water combined, suggesting a chelating effect
by rice grains, or concentration of arsenic because of water evaporation during cooking,
or both. Studies by Carbonell-Barrachina within the framework of the TIPOT project (see
other project reports) reach the same conclusion. There are several other studies on
arsenic contamination on vegetables and fish (e.g. Das et al, 2004; Burlo et al., 1999;
Carbonell-Barrachina et al., 1999; Carbonell-Barrachina et al., 1997). It would appear
that in the rice-dominated diets of West Bengal, the intake of arsenic from food depends
more on the concentration of arsenic in the cooking water than food itself. This would
imply that for the health problem of West Bengal, the arsenic contamination of drinking
water is of much greater urgency than of the irrigation water.
Standards for irrigation water
If we want to address the issue of contaminated irrigation water despite the fact that
drinking water should prevail, it would be good to assess the tolerable amount of arsenic
in irrigation water. Next to arsenic levels, it would be good to know other standards for
water quality used for irrigation in order to study the option of surface water (perhaps in
addition to groundwater). In order to say more about possible alternatives, it would be
good to know the amount of water needed, quality of the water needed (in terms of As
but also to which extent it needs to be purified) for which crop, for which surface, for
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which season. No standards are known for arsenic in irrigation water. Theoretically, one
could derive a standard for irrigation water from a standard pertaining to an element
further in the causal chain. The standard of 1.0 mg per person per day might be a
starting point for instance. We could then set aside 75% of this standard to the pathway
through drinking water, which would leave 0.25 mg per person per day as acceptable
burden through the food pathway. If we would then know how much food a person
digests per day, we may derive a standard of acceptable arsenic in food. If we then would
know how much the food crops take up from the irrigation water, depending on the
arsenic content of the irrigation water, we arrive at a standard for irrigation water.
Knowledge gathered in the TIPOT project could be helpful in these calculations.
3.4 The arsenic problem in local perceptions
ccording to current literature, awareness in the rural remote areas is still very low.
Chakraborti et al. (2002) mention that among 11,000 villagers afflicted with
arsenical skin lesion(s), when asked the reason for their disease, that 40% responded that
it was a ‘curse or wrath of God’ and 50% did not know the reason. Paul (2004) conducted
a study on the level of knowledge among rural residents regarding arsenic poisoning in
medium and high risk regions in Bangladesh. Table 1 shows the average knowledge
scores. This table shows that the average composite knowledge score for the study area
is only 19 out of a maximum score of 40. Of the 356 respondents, 35 (10%) had never
heard of the groundwater arsenic contamination problem (all these respondents came
from the low risk region). The table also indicates that 92% of all respondents in the
medium risk region and 76% from the low risk region knew that the manifestation of
arsenic-related symptoms in the villages studied was due to arsenic contaminated tube
well water, but a considerable number of respondents were unaware of the cause of the
contamination. Nearly 50% of the respondents in both study sites who were aware of the
arsenic contamination were not entirely familiar with the signs, symptoms, and diseases
caused by the ingestion of arsenic contaminated water. Additionally, nearly two-thirds of
all respondents were not able to correctly specify the incubation period for visible
symptoms associated with the consumption of arsenic through contaminated drinking
water. A similar percentage of respondents were unaware of the various arsenic
mitigation techniques available and potential solutions to the arsenic problem.
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Thus, the study showed that arsenic awareness is not widespread in the study villages,
and that there are gaps in arsenic knowledge regarding the diseases caused by arsenic
poisoning and mitigating measures available to prevent contamination. This study
identified arsenic risk region, level of education, gender, and age as important
determinants of arsenic knowledge.
3.5 The arsenic problem in GO perceptions
he paper of Chakraborti et al. (2002) heralds what has happened in India since the
arsenic calamity came to light in 1983, the year that the first As contaminations
among 63 patients were reported. A group of organizations worked together from 1983
to 1989 on the problem, reporting on the scope of affected areas and As related patient
cases, leading to a prediction of “a grim and dangerous future” (Chakraborti et al., 2002).
In 1987 a paper was published that caught attention by the media by which the
government could no longer ignore the issue (ibid.). In the same year Calcutta High Court
ordered to seal contaminated wells, but in practice only a few were sealed, and some
were opened again, because people were not given an alternative source of drinking
water, as was highlighted by the media (ibid.). From 1989 to 2001, the information on
the scope of the As problem increased and the problem also received lots of media
attention (Chakraborti et al., 2002). In 1995 an international conference on arsenic
pollution was held after which the government admitted part of the problem (not in full
scope and denied some of the findings), but also stated that undue panic was created by
the conference (ibid.). Chakraborti et al. (2002) state that it took the government 8 years
to accept that Calcutta has an As problem. Despite the fact that the government of West
Bengal initiated several As committees and task forces awareness if often said to be still
weak.
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3.6 Solutions for drinking water proposed and applied
here are broadly three ways to access clean water in places where arsenic is found in
the ground. The first is to tap from a clean source, the second is to clean the
source (in-situ treatment) and the third is to clean the polluted water (post-
treatment of polluted water). There is a wide range of solutions that fit in one of the
three. There is an enormous amount of literature that deals with various technologies to
access clean water (e.g. WHO, 1997; World Bank, 2005; Galvis et al., 1998, Hussain et al.,
2001, Parga et al., 2005; Howard, 2003; Ming-Cheng Shih, 2005). Johnston et al. (2001)
and World Bank (2005) give the most extensive and detailed overview of the methods. In
this section, we will give a brief description of the main solutions that are proposed and
applied, mainly based on the overview of Johnston et al. (2001), and we will briefly
discuss their strengths and weaknesses. We do not aim to be exhaustive; there are more
solutions than we describe here.
Tapping Clean Source:
Rainwater harvesting
The harvesting of rainwater seems to be the most sustainable way to access clean water.
The source may not last the whole dry season, however, and therefore promotion of
rainwater harvesting will need to be combined with other solutions. Good designs of
rainwater tanks are available and at relatively low cost (Howard, 2003). The main risks
concern the feaces that gets in the tank, especially from birds, but this is relatively easy
to deal with (ibid.). Besides, close to urban areas, and when metal roofs are used,
collected rainwater can contain unsafe levels of lead and zinc, and possibly other metals
(Johnston et al., 2001).
The World Bank (2005) reports some social issues regarding rainwater harvesting, namely
that (1) some users don’t like the taste of the water, (2) that it has been reported from
Bangladesh that the return to rainwater harvesting may be viewed as a step backwards to
several decades ago when it was quite widely used.
Surface water
The per capita available surface water in arsenic affected areas of West Bengal is about
7000 cubic meters (Hossain et al., 2005). During the monsoons, the average annual
rainfall in this region is about 1600 mm (ibid.). In addition, West Bengal is richly endowed
with other available surface water resources such as wetlands, flooded river basins,
lagoons, ponds, and ox-bow lakes (ibid.). This available surface water can be tapped as
an important source of drinking water. However, surface water is often heavily polluted
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with feaces as a result of poor sanitation and hygiene and it may also be contaminated
with chemicals from industrial or agricultural runoff, such as heavy metals, pesticides,
phosphate or nitrate. Surface water is usually free from arsenic contamination. However,
there are cases where surface water was contaminated because the source of the water
originates from arsenic rich rocks (Johnston et al., 2001) or waters affected by mining
activities (World Bank, 2005). Surface water always needs to be purified. Usually, it is best
to include multiple barriers to purify surface water (Johnston et al., 2003). They often
start with sedimentation to remove coarse suspended solids that could clog filters or
reduce disinfection efficiency and can remove at least 50%, and up to 90% of turbidity
and suspended solids (Johnston et al., 2001). This is followed by coagulation and
filtration (see Johnston et al., 2001) or alternatively the inexpensive alternative to
coagulation, slow sand filtration (see e.g. Galvis et al., 1998; Graham and Collins, 1996)
or bank filtration, where water, originating mainly from the river , is pumped up at a
short distance from the river (see e.g. Johnston et al., 2001). Johnston et al. (2001)
mentions that slow sand filtration will not efficiently remove arsenic or agricultural
chemicals such as pesticides. Further, the water might still be needed to be disinfected to
kill pathogens by boiling, ultraviolet (solar or artificial) radiation (e.g. Acra et al., 1989;
EAWAG, 1999), or chlorination (see Singer, 2000; WRC, 1989; WHO, 1997b).
Dug wells or ring wells
Dug wells are traditionally the most well-known method of groundwater use. The water
from dug wells has been found to be relatively free from dissolved arsenic and iron, also
in locations where neighbouring tube wells are severely contaminated (World Bank,
2005). The World Bank provides an example of a case in western Bangladesh where a 30
m deep tube well with a groundwater arsenic concentration of around 2,300 Qg per litre
is located just a few meters from an 8 m deep dug well with an arsenic concentration of
less than 4 µg per litre.
The reasons for the relatively low concentrations of arsenic in dug wells are not fully
known, but possible explanations include (ibid.):
• The water in the dug well slowly oxidizes due to its exposure to open air, large
diameter and agitation during water withdrawal which can cause precipitation of
dissolved arsenic and iron (ibid.).
• Dug wells accumulate groundwater from the top layer of a water table, which is
replenished each year by arsenic-safe rain and percolation of surface waters through the
aerated zone of the soil (ibid.).
Construction of such wells with cement ring walls provide bacteria free water, if the place
is sunny and without trees. Caution should be taken however; the water should be well
prevented from bacterial contamination etc. Recommended is to completely seal the well
and withdraw the water by a hand pump. However, the lack of oxygen then might put the
oxidation process at risk.
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The water can be treated further with simple sand filters, or chlorination for disinfection.
A report of SOS arsenic.net describes a project that promotes the development of dug
wells in Bangladesh. “…..with a very limited budget has a big impact…..Dug wells and
rainwater harvestings have shown that arsenic free water can be obtained at low cost (i.e.
50 USD).” (sos-arsenic.net/english/project2003/project-reportaugust03.html#sec6). A
list of advantages according to this webpage is as follows:
• Dug wells are indigenous technology in Bangladesh.
• The wells are cheaper and easier to construct and less susceptible to bacteriological
contamination (BRAC, August 2000).
• Natural biological filtration occur, when water percolates through sand bodies (develop
microbial flora whose metabolism contributes to the effectiveness of removing effluents).
• In dug wells within the standing water simple sedimentation take place and has been
found frequently a substantial reduction in BOD (Biological Oxygen Demand).
• Natural iron coagulation and settlement occur within standing water (decrease in
arsenic, suspended solids, ammonia, nitrate and phosphate content. Care has to be taken
however, despite the tendency for low arsenic concentrations in dug well waters, not all
are found to be below acceptable limits (World Bank, 2005). Water testing is thus
necessary. Besides, they may run out of water supply during the dry season.
Deep tube wells
Deep tube wells are an attractive option. The middle-level aquifer contaminated with
arsenic is passed over and the risks on microbial hazards are low because of the natural
filtering of aquifer materials, and long underground retention times (Johnston et al.,
2001). Questions arise though on the sustainability in terms of arsenic leaching into the
deep layer and in terms of the sinking of water table. There is still the risk on arsenic, but
this is most likely because of the uncertainty of the depths of the deep tube wells that
have been tested positive on arsenic contamination (Howard, 2003). Besides, there is still
uncertainty on the arsenic movement in the sub-surface and the scale and degree of
arsenic contamination in the deep aquifer (ibid.). The initial capital costs of deep wells
are around 700 and 800 USD (World Bank, 2005). Chakraborti et al (2002) report that
some newly constructed deep tube wells where initially no As was found, were found As
positive after some time. They also report that the analysis of 2146 deep tube-wells
(100–450 m) from six districts showed 22.3% of the samples to contain more than 10 Qg
per litre As and 9.9% to contain more than 50 Qg per litre As. Chakraborti et al. (2002)
further state that water in deep aquifers takes decades, even centuries, to accumulate
and is inadequately replenished by rainfall.
Rapid depletion of deep aquifers results in a deleterious influx from the As contaminated
aquifer above. Intensive efforts to provide deeper tube-wells for supplying drinking water
Subterranean Arsenic Removal: Experiment to Delivery
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may be counterproductive if the aquifer is simultaneously depleted by irrigation
demands. The New Scientist (December, 2005; p5) reports that in Bangladesh the deep
aquifers from which allegedly arsenic-free water is extracted receive an arsenic top-up
every rainy season. Fendorf (Stanford University) speculates that arsenic gets into the
aquifers when seasonal flood water trigger its release from sediments close to the
surface, transporting it down into the aquifers.
Pre-treatment (In-situ treatment): Clean the Source:
The technology that is tested in the TIPOT project is an in-situ treatment. Quoting World
Bank (2005) on this technology:
“In situ oxidation of arsenic and iron in the aquifer has been tried in Bangladesh under
the Arsenic Mitigation Pilot Project of the Department of Public Health Engineering (DPHE)
and the Danish Agency for International Development (Danida). The aerated tube well
water is stored in feed water tanks and released back into the aquifers through the tube
well by opening a valve in a pipe connecting the water tank to the tube well pipe under
the pump head. The dissolved oxygen in water oxidizes arsenite to less-mobile arsenate
and the ferrous iron in the aquifer to ferric iron, resulting in a reduction of the arsenic
content in tube well water. Experimental results show that arsenic in the tube well water
following in situ oxidation is reduced to about half due to underground precipitation and
adsorption on ferric iron. The method is chemical free and simple and is likely to be
accepted by the people but the method is unable to reduce arsenic content to an
acceptable level when arsenic content in groundwater is high.”
Johnston et al. (2001) state that the technique should be considered with caution. First
they state that oxidants are by definition reactive compounds, and may have unforeseen
effects on subsurface ecological systems, as well as on the water chemistry. Secondly,
they mention that care must be taken to avoid contaminating the subsurface by
introducing microbes from the surface. Finally, at some point pore spaces can become
clogged with precipitates, particularly if dissolved iron and manganese levels are high in
the untreated water.
The technology tested in TiPOT & the World Bank DM 06-880 project is a modification of this
technology using electrical power & superior aeration techniques.
Subterranean Arsenic Removal: Experiment to Delivery
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Post-treatment of Arsenic Rich Water:
Many solutions are found to remove arsenic from the water. There are many sources that
describe and compare the various technologies, for instance Parga et al. (2005), Johnston
et al. (2001). Parga et al. (2005) describe that the removal efficiency for arsenic is often
much lower for As(III) than for As(V) by using anyone of the conventional technologies for
elimination of arsenic from water, so either elevation of pH or oxidation of arsenite to
arsenate is considered a prerequisite for any treatment method to be efficient. Table 2
gives an overview of technologies that remove arsenic from the groundwater, taken from
Parga et al. (2005) with data from Johnston et al. (2001) and some other sources added.
The most common arsenic removal technologies are grouped into the following four
categories:
• Oxidation
• Coagulation
• Sorptive filtration
• Membrane filtration
Sources: Parga et al. (2005) with data from Johnston et al. (2001) and some other sources.
Technologies
Advantages
Disadvantages
Removal
(%) and
cost
Oxidation/precipitation; reactions that reduce (add electrons to) or oxidize (remove electrons from)
chemicals, altering their chemical form (Johnston et al., 2001). Oxidation is often done as pretreatment to
convert arsenite (As(III)) to arsenate (As (IV)).
Air oxidation
• Relatively simple, low-cost
• Also oxidizes other inorganic and
organic constituents in water
• Mainly used as pre-
treatment
• Oxidation process is very
slow taking weeks.
80
Chemical oxidation
(e.g. chlorine, ozone,
permanganate,
Hydrogen peroxide,
Solid manganese)
• Oxidizes other impurities and kills
microbes
• Relatively simple and rapid
processes
• Minimum residual mass
• Common chemicals that are
available
• Efficient control of the pH
and oxidation step is
needed
90
Subterranean Arsenic Removal: Experiment to Delivery
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Coagulation/co-precipitation: Coagulation with metal salts and lime followed by filtration is a well-
documented method of arsenic removal from water (World Bank). A coagulant is added to contaminated
water. After adding the coagulant, the water should be stirred, allowed to settle, and filtered for best
results. Coagulation improves parameters such as turbidity and color, and can reduce levels of organic
matter, bacteria, iron, manganese, and fluoride, depending on operating conditions (Johnston et al., 2001).
If arsenic is present as arsenite, the water should be oxidized first.
Alum coagulation
• Durable powder chemicals are
available
• Relatively low capital cost and
simple in operation
• Generates arsenic rich
sludge
• Low removal of arsenic
• Pre-oxidation required
(low removal of As (III))
• Optimal over a relatively
narrow pH range
90
Relatively
inexpensive
Iron coagulation
• Common chemicals are available
• More efficient than alum
coagulation on weigh basis
• Generates arsenic rich
sludge
• Medium removal of As(III)
• Sedimentation and
filtration needed
94.5
Relatively
inexpensive
Electrocoagulation
with air injection
(Parga et al., 2005)
• The EC process operates on the
principle that the cations produced
electrolytically from iron and/or
aluminum anodes enhance the
coagulation of contaminants from an
aqueous medium.
• Removes both As(III) and As(V)
• It does not require the addition of
chemicals or regeneration and has a
high efficiency rate.
- -
Lime softening • Lime (Ca(OH)2) hydrolyzes and
combines with carbonic acid to form
calcium carbonate, which acts as the
sorbing agent for arsenic removal.
• Most common chemicals are
available commercially
• Readjustment of pH is
required
• Large coagulant doses are
required and thus generates
large volume of waste
91
Relatively
inexpensive
(more
expensive
than
iron/alum
coagulation
)
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Sorption techniques: The efficiency of sorption techniques depends on the use of an oxidizing agent as an
aid to sorption of arsenic. Saturation of media (i.e. when the sorptive sites of the material have been
exhausted and the medium is no longer able to remove the impurities of the water) takes place at different
stages of the operation, depending on the specific sorption affinity of the medium to the given component
(World Bank,….) and the total run lengths (Johnston et al., 2001).
Activated alumina • Relatively well known and
commercially available
• Needs replacement after
four to five regeneration
(less than iron exchange
resin)
• Generates arsenic rich
waste
• Works best in slightly
acidic waters (pH 5.5 to 6)
• Water containing arsenite
should be oxidized before
treatment.
88
Moderately
expensive
Iron coated sand
(UNESCOPRESS, 2005)
• Cheap sand coated with iron oxide
is a by product of water cleaning
stations (that use sand to remove Fe
from water)
• Remove both As(III) and As(V)
• It is easy to use, requires no power
and can be produced locally.
• A family filter (now produced for
less than 30 euros per piece) can
produce 100 liters of arsenic-free
water per day
• Replacement of sand
necessary each year
• Produces toxic solid waste
93
Cheap
Ion exchange resin
• Well-defined medium and capacity
• The process is less dependent on
pH of water
• Exclusive ion specific resin to
remove arsenic
• If arsenic is present as
arsenite, the water should
be oxidized first because it
only removes arsenate
(Johnston et al., 2001).
• Requires high-tech
operation and maintenance
• Regeneration creates a
sludge disposal problem
• Run lengths determined
by sulphate, thus resins are
only appropriate in waters
with under 120, preferably
under 25 mg/L sulphate
(Johnston, .
• Limited life of resins
87
Moderately
expensive
Dolomite • Remove better arsenate than
arsenite both As(III) and As(V)
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Biosorbent
(Murugesan et al,
2006)
• arsenic removal with the waste
produced during black tea
fermentation (the tea fungus)
• an effective biosorbent for As(III)
and As(V);
• The metals in the waste can be
desorbed from the mat and the mat
can be easily degraded which is not
possible in chemical adsorbents.
Membrane techniques These make use of synthetic membranes, which allow water through but remove
many contaminants from water including bacteria, viruses, salts, and various metal ions (World Bank…).
They are of two main types: low-pressure membranes, used in micro-filtration and ultra-filtration; and
high-pressure membranes, used in Nanofiltration and reverse osmosis (ibid.). See Ming-Cheng Shih (2005)
for an overview of membrane technologies.
Nanofiltration
Well-defined and high-removal
efficiency
• Very high-capital cost
• Pre-conditioning
• High water rejection
95
relatively
expensive
Reverse osmosis No toxic solid waste is produced High tech operation and
maintenance
96
relatively
expensive
Electrodialysis Capable of removal of other
contaminants
Toxic wastewater produced 95
?
The costs of the technologies are of great importance. To have some idea of the costs
that are involved, Table 3 and Table 4 give an outline of the costs of various technologies
applied in Bangladesh and in India.
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Conclusion
The overview shows that there is no simply best option, and solutions will have to be
worked out depending on the circumstances. Progress appears to be possible along two
parallel tracks:
(1) Technological improvement within the separate groups of options (rainwater, surface
water, very shallow wells, in situ treatment of shallow wells, add-on technologies of
shallow wells, deep wells).
(2) The development of measurement- and assessment systems that may efficiently
indicate which (combination of) technologies is most appropriate in a given situation
(water sources, aquifers, economic capacities, population density, etc.).
In all this, rainwater and surface water appear to deserve much attention as a source for
both potable and irrigation water. A restructuring of irrigation towards surface water may
help safeguard the low arsenic levels in deep wells.
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Comparison of Costs of Different Arsenic Treatment Technologies in India
Source: World Bank Report
3.7 Solutions for drinking water applied in West Bengal
ince 1997, the government West Bengal, the World Bank, UNICEF, WHO, and other
international aid agencies and with NGOs have initiated a two-phase program to
combat the arsenic crisis (Hossain et al., 2005). The first phase was to identify
contaminated tube wells and the second to provide clean drinking water. Tube wells were
painted green or red corresponding to arsenic concentrations below and above 50 Qg per
litre (the national standard), respectively, utilizing field kits for arsenic testing. But, the
tests kits turned out not to be reliable; false negatives were as high as 68% and false
positives up to 35% (Rahman et al., 2002). Of the 2000 arsenic removal plants (that
capture the dissolved arsenic using ferric salts) installed in villages in West Bengal, four
out of five are either abandoned or deliver smelly and discoloured water (New Scientist,
2004). Based on an interview with Chakraborti the article also states that India has so far
spent three million US dollars on plants to capture the dissolved arsenic using ferric
salts and that of the 20 percent of removal plants still apparently functioning well, many
are not removing arsenic to the required standard, mainly because villagers do not know
how to maintain the plants. More details are provided by Hossain et al. (2005). The paper
evaluates the efficiency of 18 ARP (Arsenic Removal Plants) projects from 11
manufacturers. None of the plants could achieve the WHO standards of 10 Qg arsenic per
litre and only two achieved the Indian standard of 50 Qg per litre. The urine samples of
the villagers in the project’s area were found that 82% contained arsenic above the
normal limit.
S
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EFFORTS FOR ARSENIC MITIGATION IN WEST BENGAL, INDIA
Sl.
No.
Organization Type of work
1. Natural Environmental Engineering
Research Institute (NEERI)
Arsenic determination field kit
2. Central Ground Water Board (Eastern
region)
Monitored arsenic affected areas w. r. to
water samples / soils and determined the
arsenic free aquifer
3. Central Glass and Ceramic Research
Institute (CGCRI)
Ceramic membrane filter units which are now
in operation at selected areas of North 24
Parganas
4. All India Institute of Hygiene & Public
Health (ALLH&PH)
Co-precipitation methodology using different
types of coagulant followed by filtration. The
Institute developed also the adsorption
methodology.
5. School of Environmental Studies
(SOES) Jadavpur University
Pellets to be used as coagulant followed by
filter candle
6. Bengal Engineering College, Deemed
University
Adsorption methodology using activated
alumina. (Amal filter)
7. Indian Institute of Technology (IIT,
Kharagpur)
Static or batch dynamic or column adsorption
studies
8. Analytical Chemistry Department,
Kalyani University
Monitored the arsenic affected areas and tried
adsorption methods
Hossain et al. (2005) summarise the causes of the poor performance as follows:
• Maintenance. The manufacturers did not give the correct directions regarding “forward
washing”.
• Clogging. The problem of sand gushing was not taken into account.
• Lack of user friendliness The system provided both arsenic free water (for drinking) and
arsenic polluted water (for other purposes) and there was no prevention of tapping
“wrong” water.
• Poor management of sludge from the plant.
Subterranean Arsenic Removal: Experiment to Delivery
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3.8 Solutions for irrigation water proposed and applied:
s far as we know, literature on arsenic contamination of irrigation water concerns
mainly the effects of arsenic polluted water on the amount of arsenic in the crops
and the resulting health impacts. However, no specific solutions are put forward for the
use of poisoned irrigation water. As we have seen in the previous section, there are three
ways of having access to clean water. We will discuss what these solutions would have to
offer for irrigation water. It is important to keep in mind that (1) irrigation water concerns
large quantities, that (2) that the options to access clean water are often costly and (3)
that clean water is scarce and that groundwater is affecting the deep aquifer.
Broadly stated by Chakraborti et al. (2002), up to now, no efforts have been made to
adopt effective watershed management to harness the extensive surface water and
rainwater resources in West Bengal. Proper watershed management and participation by
villagers are needed for the proper utilization of water resources and to combat the As
calamity; there are huge surface resources of sweet water in the rivers, wetlands, flooded
river basins, and oxbow lakes. More specifically, tapping water from clean sources may
offer access to clean water, but only at a certain period of the year. Harvesting of
rainwater may form some buffer before the dry season starts, but it will not last. Surface
water offers a good source when being close to a river. Or, a big pond may offer enough
water for a certain period. The need for irrigation water however, is the highest during
the dry season when water is scarce. Concerning DM06-880’s technology of in-situ
treatment of shallow wells, it may be noted that if the technology would work well indeed
for drinking water purposes it might be up-scaled to also supply arsenic-free irrigation
water.
A
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4
The Design
4.1 Design criteria
4.2 Options available: Variants
4.3 Line Diagram of SAR Plant
4.1 Design Criteria
4.1.1. Technical Criteria:
he water delivered need to require the standard quality (both chemical and
bacteriological) and required quantity, throughout the various seasons.
Technologies should be reliable and robust, with little possibilities for faults due to
weakness or obvious user error. In our case, it is a prerequisite that the technology is
protected against overdraft for instance.
The technology is not allowed to have any adverse effects on the environment. One of the
big advantages of in situ treatment is that there is no waste as is the case with many of
the technologies of arsenic removal.
4.1.2. Socioeconomic Criteria:
Economic considerations - Everyone should agree that safe drinking water is a basic
human right and that national governments and society at large should ensure that all
members of society have equitable access to meet basic needs for safe drinking water.
T
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The costs of technologies are of great importance. If the there are no water cleaning
stations using sand to remove iron from the water in the neighbourhood, it is the option
of iron coated sand is not feasible.
Institutional considerations - Awareness raising, technology identification and
verification, application and monitoring of arsenic mitigation which will all require
coordination and understanding by various public and private representatives.
Gender considerations - The technology should not put and extra burden on women,
that are in most developing countries responsible for the provision of water and the
technology should at least be gender neutral in terms of ergonomic, culture and time.
Convenience and Social Criteria - implies a necessary level of convenience required for
the users and the existing social regulations. The effort required to go to the safe
communal source and wait in a queue for one’s turn to collect water should to take into
account and the amount of effort that the users are willing to put into it.
The technology should be socially accepted, preferably blend into the existing water
supply, suitable and sustainable in terms of the local topography, hydrology, socio-
cultural conditions, settlement pattern and population density.
4.1.3. Site Selection Criteria:
For all designs, the obvious assumption is that the SAR (Subterranean Arsenic Removal)
works at that particular location where:
• Sufficient underground iron is present,
• Soil structure at filter depth not too coarse (which would lead to no absorption surface)
• No strong groundwater flows overloading the absorption zone.
• Moreover, we may assume a delivery factor at the safe side, namely 1:4. For every 4
litres pumped up, 3 can be used for drinking water and 1 is needed for recharge.
4.1.4. Cost elements:
Assuming the SAR technology works, one of the decisive factors for its success will be the
costs. All the materials needed for the designs are locally available and the costs of the
materials are relatively low.
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4.2 Options Available: Variants
rom the TiPOT project, three variants were recommended for use in the Eastern
India. These are: T-200000l (Panchayat Hold) for large community of around 400
households, T-6000l (Group of Household) for smaller community of around 100
households & T-700l for one house. The T-700l has 2 variants viz T-700E & T-700M –
the first electrical operation & the second manual operation.
4.2.1 Model T-20000L – Panchayat Hold
T20000L is designed to deliver 20,000
litres of water during one recharge cycle.
If we assume one cycle daily (with
recharge usually taking place during the
night), this can supply 400 households
with 50 l per day (10 l per capita per
day). Walking distances to fetch the
water from the system will not be
prohibitive in areas with high population
density. Alternatively, supply pipes may
branch out from the system (ending in
automatically closing taps to prevent
spillage).
Being designed for public use, T20000L
should generate continuous water
supply, hence it needs a big supply tank
to bridge the recharge period (still
assuming a single-well system). Serving
400 families, a formal operator can be
assigned. This enables a separation of
domains: the area in front of the tank where water can be drawn is public space, but the well,
other tank and piping are closed off. Thus, users can only empty the supply tank and over-
drafting is impossible.
F
Fig: Model T-20000l
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4.2.2 Model T-6000L – Group of Household
Assuming that the system has been tested and works already, we describe the hardware
and how it works. This is a unit designed as a small-scale add-on to an existing well of
filter length 6 m. Due to this filter (and its resulting absorption zone), the recharge
volume is 2 m3, the supply volume is 6 m3 and the total water throughput in a cycle is
thus 8 m3. This is not stored in a single tank as in T700 but in two tanks. The recharge
tank has a working volume of 2 m3 and extra overhead of at least 1 m3 for the shower
heads for aeration.
The supply tank can be between 2 m3 and 6 m3. A small supply tank requires more
frequent starting of the pump. The supply tank should be big enough to have water for
cooking and drinking available when recharge is taking place. A larger supply tank
enables continuous water supply. With 2 m3 storage, for instance, users in most cases
will not need to
change behaviours
during recharge.
Adjusted to the
supply tank is a pipe
with a self-closing tap
or it may be
connected to any
existing supply piping
system (where self-
closing taps could be
constructed for saving
of water as well). The
supply tank is present
especially to prevent
overdraft. Because of
that tank, the water
pressures in the
supply piping system
do not affect the
water pressures at the
well. This enables a
‘hard-wired’,
automatically balanced filling of the recharge tank.
Between well and tanks, the pipes are split in a T. One arm goes to the recharge tank
(with showerheads etc.) and the other to the supply tank. The diameters of the pipes are
selected such that their total resistance compares as 1: 3, so that for every 4 litres
Fig: Model T-6000l
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pumped up, 3 litres are for use and 1 litre to the recharge tank. The recharge tank is 3
m3 with a hole and overflow pipe at the 2 m3 level. Full level of the recharge tank thus
automatically implies that 6 m3 has been delivered through the supply tank.
A sensor may be installed in the recharge tank that indicates that the recharge tank is
full. When the operation is automatic, the sensor may disconnect the well from the supply
tank and recharge starts. When the operation is manual, the sensor may block the power
to the pump once the recharge tank is full. Without sensor, users might be tempted to
ignore the overflow and continue pumping (= over-drafting). The sensor can prevent
this. If the system is run by an institution such as a school, the risk of over-drafting is
small anyway because the recharge task can be assigned to someone. Finally, there are
two cleaning pipes with valves for cleaning the tanks.
As with T700M, the risk of this set-up is that the 1:3 ratio is not maintained because of
clogging in the showerheads or elsewhere. To prevent this risk, the two tanks might be
placed in sequence in stead of parallel, so that the recharge tank is filled first and starts
to overflow into to supply tank when full.
4.2.3 Model T-700M – Household Manual Model
The design needs to be such that of each amount of water pumped, a fixed part will flow
in the recharge tank. This
might be designed such that
the water will flow through a
pipe and that the pipe is split
in a T. One arm goes to the
recharge tank (with
showerheads etc.) and the
other is an open flow that can
be used. The diameters of the
pipes are selected such that
their total resistance compares
as 1: 3, so that for every 4
litres pumped up, 3 litres are
for use and 1 litre to the
recharge tank. The recharge
tank is about 0.6 m3 with a
hole and overflow pipe at the
300 litres level. The 300 litres
left is used for the shower
heads and aeration. Full level
of the recharge tank thus automatically implies that 700 litres have been delivered
Fig: Model T-700M
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through the supply pipe. There is one cleaning pipe with valve for cleaning the recharge
tank.
The disadvantage of this design is that the ratio of 1:3 as the automatic split between
water for recharge and water for use can shift in the course of time without the user
noticing this, e.g. because the shower heads become somewhat clogged. The design
must be rethought to prevent this. One option is to install two smaller tanks in sequence.
People first fill a recharge tank of 300 l and if that tank is full, it overflows into a small
consumption tank of, say, 100 litres. If that tank is full, recharge can take place while
people still withdraw water from the consumption tank. After the recharge tank is empty
and a few hours of waiting, both tanks can again be filled in sequence. This system is
safe in the sense that there is always enough water for recharge, but people have to take
care to actually do the recharge after emptying the consumption tank 10 times. This
could be prevented by a bigger consumption tank (1000 l) but then people would have to
fill 1,300 l in one go, which is unattractive.
4.3 Line diagram of the SAR plant
top ground surface
groundwater table
supply/drain
check valve
water meter
sampling point
aeration
power supplyswitcher
valve
sampling point
pump
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5
Providing the SAR Utility
5.1 Selection Criteria of the Project Sites
5.2 Survey Methods
5.3 Arsenic & iron levels at the Project Sites
5.4 Installing the Plants
5.5 Starting the Operation & Data Generation
5.6 Delivering Water & Quality Monitoring
5.7 Realising Problems & Prospects
5.1 Selection Criteria of the Project Sites:
he site selection procedure has been guided by five main considerations, i.e.
1. where the arsenic contamination of groundwater remains to be a major concern
2. where there is no alternate source of potable water
3. where there is a general willingness to pay
4. where electricity is available, and
5. where iron concentration is high (As:Fe=1:10 or more)
High concentration of Arsenic: The areas selected for plant installation are suffering
from an acute arsenic problem, the arsenic content has been found to vary between 0.09
to as high as 0.28 mg/l (WHO permissible limit is 0.01 mg/lt). These values have been
T
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recorded from previous studies, analysed by FOSET and also verified by our own
laboratory analysis done by the research assistants of this project.
Scarcity of alternate sources of potable water: Alternate source like pond water is
infested with bacteriological, heavy metal & oil contamination. The present supply lines
from comparatively safe deep tube wells lack proper maintenance. As a result, the local
people, being aware of the ill effects of arsenic are still compelled to use arsenic
contaminated water for the washing of utensils & vegetables. In some areas, safe
drinking water is supplied by local van pullers @ Rs. 10 (0.2 USD) per 15 lt which is
unaffordable by most of the families belonging to BPL (Below Poverty Level).
Willingness to pay: The willingness to pay is a vital issue for sustenance of the project
because in future, the community is going to look after the plant on their own. This will
provide a source of income for the household operator/Central Actor in charge of the
plant. Keeping in mind the economic condition of the poor community residing in the
selected sites, we have decided to charge a minimum of Rs10 (0.2 USD) per month for
drinking & cooking water. The main problem is that, the people is not habituated of
paying money (whatever small the amount may be) for the natural resource which is till
now available free of cost. So, before anybody starts to pay, we have to convince them
the importance of drinking safe water. This will obviously need some time & till then,
RKVM can pay the meager amount of electric bill (6 USD max) required for running the
plant. So, the target of WTP is to ensure that the beneficiaries are able to pay at least Rs
10 or 0.2 USD per month in future.
Electricity: Earlier, this same principle of aeration was tried in Bangladesh. But it did not
work as expected probably due to these three reasons: i. hand pump was used ii. Iron
concentration in water was not sufficiently high & iii. Aeration technique was not efficient
enough. So, to avoid these defects, the system has to be mechanized as far as possible.
Submersible pump is must for the system to work desirably. So, electric connection is
required in the project site.
High iron concentration: Iron should be at least 10 times more in concentration than
arsenic in the groundwater. Iron is the main agent for co-precipitating arsenic. So
sufficiently high iron concentration in the aquifer is a must.
Keeping these points in mind, the following sites have been selected by the Project Team:
1. Merudandi Village, Bashirhat, N 24 Parganas
2. Naihati Purbapara, Bashirhat 5 No Ward, N 24 Parganas
3. Rangapur Village, Nilgunj, N 24 Parganas
4. Tepul Village, Gobordanga, N 24 Parganas
5. Ghetugachi Village, Chakdaha, Nadia
6. Naserkul Village, Ranaghat, Nadia
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Location of India
Study Area: West Bengal in the Eastern part of India in the Ganga-Brahmaputra Delta Region
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Source: School of Environmental Studies, Jadavpur University, Kolkata-32
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5.2 Survey Methods
5.2.1 Socio-economic & Willingness-to-pay Survey:
ere, a case study is being provided that was followed in the villages of N 24
Parganas & Nadia. In order to achieve the objectives of the study, the proposed
research design was tested in a peri-urban locality for a range of economic and
environmental conditions. In this study that covered 50 households, consumers were
provided with necessary information on the use of contaminated groundwater and its
adverse ill effect. The consumers were presented with the hypothetical situation where
they would be provided with arsenic free water and asked if they would be willing to pay
for it. The study was conducted in North 24 Parganas district (Kasimpore), approximately
25 km from the main city Calcutta in India. The total area of the study area is 2.0 km2,
with the population of 3700 people. The average annual income of the families is
US$800/annum.The main source of water in the area is 20 shallow wells and tube wells
which are used for drinking as well as irrigation purposes. The area was chosen because
it was known that 70% of the tube wells in the area had arsenic concentrations above
0.05 mg/l. The questionnaire for the survey is designed to determine the maximum
amount of money the household is willing to pay for a commodity or service. WTP studies
are also termed “contingent valuation” studies because the respondent is asked about
what he or she would do in a hypothetical (or contingent) situation. The interview
questionnaire is designed and pre-tested, usually drawing on discussions with local
families or community (Panchayat) leaders. Initially a draft questionnaire had been
prepared and checked and was amended with a group of specialist before it took the final
form. In each questionnaire, an explanatory letter was attached to explain the ethical
considerations and to facilitate the questionnaire filling.
Selection of the attributes
The model used the following variables to ascertain the consumers’ WTP for water:
• Consumers’ perception and satisfaction about the present quality of water used
for drinking and cooking
• family income
• household size
• water consumption in the family
• awareness about arsenic in the area
• age
• education of the head of the family who takes the decision
• means of getting the drinking water ( owned tube well or community)
• the health condition of the family members
• the value of the Start Bid (SBID) made
H
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Because of the dichotomous structure of the dependent variable (WTP), a non-linear
probabilistic model had been used for estimation.
1. The pre-requisites of the survey is proper planning to cover the command area,
securing institutional support for the research to go forward and the permission from
the local authorities to carryout the survey.
2. WTP or willingness to pay study requires simple household surveys in which a
member of the household is asked a structured series of questions.
3. The questionnaire is designed to determine the maximum amount of money the
household is willing to pay for a commodity or service.
4. The questionnaire is designed in the local language (Bengali), as most of the target
population may be unfamiliar with the English language.
5. The questionnaire has different sections. The first section is related to the
background of the respondent (personal profile) including his education level,
financial status as well as the occupation and household composition. This section is
designed to gain information about the respondent's social, economic and
demographic characteristics, and establish a conversational rapport with the
respondent.
6. The second section is about the current situation of the potable water supply service
such as quality, quantity and mode of procurement, the customers’ satisfaction,
awareness about arsenic in the groundwater, WTP, ability and affordability and water
consumption. Respondents were asked about their awareness about arsenic and their
satisfaction level with the present water quality.
7. Then, a hypothetical condition of supplying arsenic free water for cooking and
drinking purpose is portrayed. The respondents are provided with two placards. One
is scenario A, where the respondent is shown how the present way of using shallow
tube well water mostly contaminated with arsenic tends to damage the health of the
family including the respondent. The other is Scenario B, where the detrimental
trends of health can be halted with the use of arsenic free water for drinking and
cooking purposes.
8. The last section is designed to measure the WTP by contingent valuation method
using bidding games (either descending or ascending order). In the bidding game,
the respondent is offered an initial bid amount and was asked whether he or she
would be paying this amount in future. The response is obtained on dichotomous (yes
or no) scale. For a negative response, the amount is to be reduced in steps. If any of
the answers is yes, the respondent is considered as WTP for obtaining the water and
the corresponding amount was the willingness to pay. If all the answer is no, the
respondent is considered as not WTP. In the event of WTP response being yes, the
amount was raised and the next bid was made till a 'no' answer determined the upper
limit of WTP.
The questionnaire has been attached in the Annexure
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Correlation analysis
The correlation coefficient between each of these variables and WTP has been estimated
to check their degree of association. In many cases, the correlation coefficients are found
to be significantly high (Table 1). As expected, the correlation between WTP and income
of the household, awareness about arsenic, dissatisfaction (no satisfaction) with respect
to quality of water as perceived by the respondent, health condition of the family are
significantly positive. On the other hand, the correlation coefficient with respect to age,
education and occupation (agriculture=1) are found to be negatively correlated though
they are not quite significant. Contrary to maintained belief, no significant association is
observed between WTP and household size, education and water consumption. The
correlation between start bid and willingness to pay is found to be significantly positive.
Choice of appropriate econometric model
The analysis was carried out category-wise with regression coefficients obtained as
shown in Table 2. It was observed that Chi-square -values were quite significant,
indicating the goodness-of-fit of models.
Calculation of Willingness to pay
Based on the awareness level and satisfaction with the present available water quality, the
samples can be divided into sub groups (Table 3). For each of these sub-groups the
regression equation can be written as-
WTP = a + b*(expense) + c*(SBid)
For each subgroup equation, the regression equation is run to obtain the value of a, b
and c.
The alternative values of the Starting Bid (0, 10, 20, 30) and the average expenditure
estimated for each sub-group are substituted in the above equation to get the estimated
WTP (corresponding to each value of the SBID) for that particular sub-group.
Estimated revenue and cost recovery potential
The willingness-to-pay bids can be used to estimate the likelihood of connection to and
revenue generated from the provision of supplying arsenic free water. Such a
computation helps to determine whether the provision of such services would be
economically sustainable. The connection frequencies and revenue estimates is plotted in
Figure1. At Rs 20 per month the connection frequency is approximately 32 percent, while
at Rs25 the figure is 22%. The plot of revenue against monthly tariff indicates that at
Rs20/month monthly tariff, the revenue yield would be Rs680 per 100 families per
month and connection frequency will be 34%. The same revenue yield will be Rs 540 per
100 families corresponding to 36% connection frequency and Rs 550 per 100 families
corresponding to 22% connection. Therefore, any tariff in the range of Rs 20 per month
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should achieve the dual objectives of a reasonably high connection frequency and high
cost recovery.
Decision
Arsenic contamination of groundwater is an issue of global concern. The objective of the
study was to determine the willingness to pay for arsenic free groundwater in a rural
setup and the factors influencing WTP. The analysis revealed the awareness amongst the
people regarding the presence of arsenic in the groundwater significantly affects the
odds of paying more for the arsenic free water. It has been observed that due to lack of
awareness about the presence of arsenic in the groundwater and its harmful consequence
amongst the people in the study area, the willingness to pay for better water quality is
quite low.
Table 1 Correlation matrix between WTP and socioeconomic values
Variables Parametrics
No of households 0.011
Water consumption 0.024
Occupation -.052
Income 0.292**
Age -.123
Awareness 0.469**
Satisfaction with present available water quality -.295*
Education of the respondent -.044
Health condition of the family -.301*
Initial Bid 0.6**
** Correlation is significant at 0.01 level( 2 tailed)
* Correlation is significant at 0.05 level( 2 tailed)
Table 2 SPSS output
Variable B S.E. Wald df Sig R Exp(B)
NO_OF_HO -.1604 1.0434 .0236 1 .8778 .0000 .8518
WATER_CO .0013 .0187 .0051 1 .9428 .0000 1.0013
OCCUPATI -1.6269 1.4135 1.3248 1 .2497 .0000 .1965
INCOME .5288 .3448 2.3517 1 .0251 .0769 7.6969
AWARENES 2.9215 1.2595 5.3804 1 .0204 .2383 18.5699
HAPPY_WI -1.6388 1.0090 2.6379 1 .0143 -.1035 .1942
AGE -.0741 .0567 1.7070 1 .1914 .0000 .9286
EDUCATIO 1.4699 1.3004 1.2777 1 .2583 .0000 0.3488
HEALTH_C -.7392 1.1944 .3830 1 .0360 .0000 .4775
MEANS_OF -2.0798 2.4473 .7222 1 .3954 .0000 .1250
SBid 0.1852 1.6761 2.3121 1 .0267 .0235 3.415
Constant 1.4689 2.9491 .2481 1 .6184
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Table 3 Estimation of median WTP
Happy/
Unhappy
with the
present
quality of
water
Aware/
not
aware
about
arsenic
No of
sampl
es
Coeff Coeff Constant Bids Avg Proj
of of income WTP
Income bid
Media
n
WTP
Not
aware
2 0 0 0 10 9000 0
20
0 Happy
Aware 6 1.41 -0.55 -0.37 10 10800 8.41
20 2.91
30 -2.59
40 -8.09
0.16
Not
aware
28 -0.04 0.97 0.05 10 4900 9.59
20 19.32
30 29.05
40 38.78
24.19 Unhappy
Aware 8 -0.02 0.79 0.35 10 6500 8.16
20 16.10
30 24.04
40 31.98
20.07
Figure: Revenue and Connection frequency vs monthly tariff (Indian Rs)
Connection frequencies and monthly revenue (per 100
households)
0
100
200
300
400
500
600
700
800
0 20 40 60 80 100 120
Monthly tariff (Rs)
Reven
ues (
Rs)
0.00
20.00
40.00
60.00
80.00
100.00
120.00
%H
ou
seh
old
co
nn
ecte
d
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5.2.2 Food Safety Survey
The main objectives of the survey were:
� To know the main sources of the foods consumed in the studied area: city
markets, own production, etc.
� To establish the mean consumption of the main foods in the studied area: for
instance, rice, pulses, fish, etc.
� To know the main ways of preparing the meals in the studied area, which will
determine, for instance, how much polluted water is used in their kitchens
� To establish the daily intake of drinking water and its source.
According to our data, the main population of West Bengal is concentrated in the age
range from 15-44 years. However, it would be very interesting to know the differences
among the different age groups. In this way, the first questionnaire will be addressed to
any person including children and old people. On the other hand, the second
questionnaire will be addressed exclusively to the mother of the household or the person
in charge of the water collection and food preparation. The questionnaires (I and II) are
shown in the Annexure.
These data can be compared with the later consumption to know the arsenic intake of the
people before & after the safe water is supplied.
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5.3 Arsenic & Iron levels in the aquifers at the Project Sites
he project sites were selected based on the deduction from the questionnaire survey
& the iron: arsenic concentration ratio.
Initially, during the site selection phase, the project team analysed the iron & arsenic
concentration of various sites from the laboratory of Forum of Scientists, Engineers &
Technologists (Programme of water Quality Testing under UNICEF supported JPOA with
Govt. of West Bengal).
The final 6 sites that were selected have the following iron & arsenic concentrations.
Sl
No Site Arsenic Conc (mg/lt) Iron Conc (mg/lt)
1 Naihati Purbapara,
Basirhat 0.1750 1.5734
2 Merudandi, Basirhat 0.2820 3.3259
3 Rangapur, Nilgunj 0.0916 3.4028
4 Tepul, Gobardanga 0.158 2.9356
5 Gotra, Ghetugachi 0.2065 2.077
6 Naserkul, Ranaghat 0.23 3.2248
Later, after installation of the plants, the water quality was monitored in the laboratory
developed in the premises of RKVM-IAS by the research assistants.
Arsenic & iron concentrations are measured with a UV-Visible Spectrophotometer having
a detection limit of 0.002 mg/lt. (The WHO guideline for maximum permissible limit for
arsenic is 0.01mg/lt. Maximum desirable limit of iron in drinking water is 0.3mg/l;
whereas, maximum permissible limit is 1.0 mg/l. No health-based guideline value for
iron has been proposed by WHO)
T
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5.4 Installing the Plants
or the purpose of plant construction, the RKVM acquired tracts of land measuring
around 3m x 4m in each of the 6 villages from interested individuals (who came forward
to donate the land for the noble cause) through mediation of Panchayat in exchange of a
token money & legal documents.
The construction phase consisted of mainly two parts viz – the installation of plant
machinery & construction of a brick room on the land for housing the tanks, valves & the
operator. RKVM acquired every material locally but sent its own mason & plumbers to do the
job fast.
On the other hand, RKVM applied for the electric connection through separate electric meter
to the WBSEDCL (West Bengal State Electricity Development Corporation). This needs a little
time & this varies from place to place depending on the supply of power. So, when our plants
got constructed, we had to take power connection from the meter of the land owner through
a sub-meter till the separate meter for the plant was issued. At present, 4 of the 6 plants
have got separate meters.
5.5 Starting the Operation & Data Generation
nce a plant is fully installed & electric connection provided, the operation was
started. Each operational cycle consisted of pumping up 6000lt ground water in the
tanks (3000 lt each in Recharge Tank & Delivery Tank). This usually takes about 50 mins.
Then, after a calculated intermission time, the water from the Recharge Tank is sent back
to the aquifer by releasing it in the boring itself by opening a valve. This recharge is done
slowly & takes about 2 hours time. The water from the Delivery Tank is drained away by
opening another valve.
During various stages of this operational cycle, 6 samples of water are collected (3 for
iron & 3 for arsenic) in 500 ml sampling bottles. This sampling is done 3 days every
week. The sample bottles are then labeled & stored away. Later, on Monday, the operator
delivers total 18 samples to the laboratory at the RKVM-IAS premises at Kolkata. At the
field, the operators have to perform a Dissolved Oxygen test to monitor the level of
oxygenation of the tank water. The chemicals required for this test is provided to the
operator by the RKVM project team.
Every operator is provided with an operating manual for plant operation & DO
measurement. (See Appendix) Also, they are given adequate training by the research
assistants & the senior operator from the earlier TiPOT project. For every sampling day,
F
O
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the operators have to fill up a log book provided to them by the project team
corresponding to every sample bottle.
At the laboratory, mainly 4 tests are done, viz, Arsenic testing by Spectrophotometric
Method, Iron testing by Spectrophotometric Method, Conductivity measurement & pH
measurement. The data is then entered into the computer & preserved.
The starting date & water delivery date of various plants are given in the following table.
5.6 Delivering Water & Quality Monitoring
ach of these plants started to produce water free of arsenic & iron below WHO
guideline (0.01 mg/lt for arsenic & 1 mg/lt for iron) within 45 – 50 days of
operation. Once the laboratory test results of the arsenic & iron came to the “Below
Detectable Limit” (BDL), the project team sent the samples to a NABL certified laboratory
for AAS testing. When their result confirmed that the water was safe to consume, the
operators were instructed to start delivering them to the people.
As the RKVM laboratory do not have a facility for bacteriological testing, the project team
used to test the Coliform, total viable count, etc from a NABL accredited laboratory.
The project team continued the monitoring of the water quality till the end of the project
period ie 31st December, 2008.
Name of Plant Starting of Operation Delivery of Water
Merudandi, Basirhat,
North 24 Parganas, WB 12th June, 2008 18th august, 2008
Purbapara, Basirhat
North 24 Parganas, WB 12th June, 2008 5th August, 2008
Rangapur, Nilgunj
North 24 Parganas, WB 10th October, 2008 1st December, 2008
Gotra, Ghetugachi,
Chakdah, Nadia, WB 20th October, 2008 16th December, 2008
Tepul, Gobardanga
North 24 Parganas, WB 3rd October, 2008 4th December, 2008
Naserkul, Ranaghat,
Nadia, WB 10th November, 2008 15th January, 2009
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5.7 Realising Problems & Prospects
fter starting of the operation, some minor problems aroused which were addressed
efficiently by the research assistants & the European Advisors.
Once, in the Purbapara, Basirhat plant on the 5th month of operation, some sands entered
the boring through the filter & the recharge efficiency decreased. So, the project team
and the plumber inspected the site & decided to aerate the boring by a compressor. After
only 1 hour of aeration, all the sands were cleared & the plant efficiency was restored.
At Naserkul, Ranaghat plant, which was started at November, 2008 only, the project team
had to quicken up the operational cycles by ordering the operator to run 2 cycles per day
with 12 hours interval. This brought down the arsenic and iron level very fast.
At Tepul, Gobardanga plant, a minor problem developed about the electrical installations
& the project team had to change & repair some of its machinery within a few days of its
starting of operation. At present, it is running smoothly.
At the Merudandi, Basirhat plant, the project team faced an unprecedented problem. The
community said that they could not get any taste in the water from the plant. Also, they
complained about loose motion after drinking the water. So, the project team tested the
water for bacteriological contamination, but failed to find any. Later, it was understood
that, there was no taste in the water due to absence of high level of iron salts (which
makes the taste of water bitter) and the loose motion was also due to the same reason. It
was observed that, when some people used the water for drinking & cooking
continuously for 2 weeks, the digestive systems habituated with the low-iron water & the
loose motion ceased. It took a lot of persuasion & campaign for the project team to make
the villagers believe that the water was completely safe & their problem was only
temporary one.
A common problem at all the sites was making the community pay for the water. In the
developing countries, natural resources usually come free of cost & the people are not at
all habituated in paying for them whatever meager the amount may be. Although, the
responses were positive during the WTP surveys, many villagers backed off when the time
came for paying. At present, a section of the community has begun to pay & this will
increase gradually. So, for the time being, RKVM will be taking care of these plants
(paying the electric bill & maintaining it) till they become self sufficient (probably within 6
months).
A
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About the prospect, the scientific data & the practical field experience revealed that the
technology is awesome & these plants are not going to be another costly showpiece
(arsenic filter) at the side of the village road.
1. Most effective & long lasting technology available till date. With regular treatment,
the arsenic level will remain Below Detectable Limit. Actually, if the plant is being run for
a few years, then the total aquifer will undergo oxidation & the water quality will improve
considerably.
2. It is also the easiest technology around. No costly chemicals & complex tray
systems & delicate filters. It is all about pump set & showerheads. Every plumber &
electrician in the village can do the operation & maintenance once they are given a simple
training.
3. The SUSTAINABLE way of treating arsenic contaminated water. This process not
only removes arsenic & iron from the water pumped out through the system, but also
treats the contaminated aquifer water. Thus, the community around the plant gets
benefited in the years to come.
4. Easy Operation & Maintenance:
a. The whole system is very cheap to operate & maintain.
b. Either an individual owner or Self-help groups under Panchayat of the village will
be able to operate & maintain it.
c. This will provide a part time job to a few individuals of the village on hourly basis.
Every day, 2 hrs is required for operation. Three or four persons in the village can be
trained up so that the plant can be operated in rotation basis under any circumstances
even in absence of any one operator. They will be paid accordingly by the
Owner/Panchayat at the end of the month.
d. Even the illiterate village plumbers & electricians are able to do the maintenance
job once they are briefed about the whole system & given a basic training.
5. More there is iron in water, more effective the process is. The arsenic gets co-
precipitated with the precipitated iron in the aquifer itself & doesn't get a chance to come
to the surface. Fortunately enough, the ground water in the Bengal Delta region in
general, has a high concentration of iron.
6. Waste disposal is not a problem. In the 1st two months, only Fe(III) precipitates
are to be discharged out of the plant. After that, no waste is generated at all since iron,
arsenic & other impurities like Mn, nitrates, nitrites, etc gets bounded under the soil in
the aquifer itself. They cease to be public menace by coming out of their place.
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7. Unlimited supply of Arsenic free water can be obtained by running the treatment
cycle for more than once per day.
8. Ramakrishna Vivekananda Mission has a strong administrative system and has a
high acceptability among the common mass. Where land acquisition & awareness
generation & making the villagers pay money for the drinking water (whatever meager
the sum is), the role of this particular organisation becomes critical. Previous experiences
in the legal matters & negotiation with Govt agencies & people becomes handy. Also,
RKVM has officially obtained the technology from the Queen’s University, Belfast.
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6
Elements of the Delivery System of SAR
6.1 Introduction to Delivery System
6.2 What is supplied?
6.3 Users, Suppliers and ‘Central Actor’
6.4 Concepts of relationship between Central Actor & Users
6.5 The relationship between Central Actor & Suppliers
6.6 Facilitators
6.1 Introduction to Delivery System
verybody is involved daily in delivery systems. The supermarket, the computer help
desk, the car repair garage, the insurance agent, they are all parts of delivery
systems of food, transport, security and so on. Yet, delivery systems are very poorly
conceptualized scientifically. What, for instance, is ‘the product’? In environmental
science, the answer is that if we aim to compare the environmental impacts of products,
we should move away from the concrete manufactured thing and compare ‘functional
units’, for example the packaging of 1 litre of milk or the provision of 1 hour of
comfortable sitting (Van den Berg et al., 1995) The poor scientific basis on delivery
systems is also visible in the arsenic problem. In the chapter on safe water technology of
the WHO report on arsenic in drinking water, for instance, we find 52 references to
literature on the natural science and health aspects of the arsenic, 99 references on the
technologies for solving the problem, but 11 references to how this technology is
supposed the reach the population. None of these is a scientific publication, but reports
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of organisations such as the International Water and Sanitation Centre (IRC), WB or
UNICEF. There is one chapter in the report focusing on social sciences, but it only gives
attention to awareness and communication with the local population and does not deal
with provision systems. Many provision systems work perfectly well in practice, but the
design of new ones is an abstract business, simply because all design is abstract
business, if we want to avoid that we just choose something because we are used to it or
because it vaguely looks good. One way or another, design implies that potential
components of a not yet- existing system are selected and assembled to form that new
system, guided by criteria such as efficiency, environment or equity. Here again, design is
something we do everyday (we make a holiday plan, we design a social tactic etc.) and yet
it is poorly conceptualized scientifically, possibly because design is a synthetic activity
that is difficult to reach with the overwhelmingly analytical devices of normal science (De
Groot 1992). In this chapter, therefore, we necessarily start out with a relatively
fundamental look on the principles for the not-yet-existing provision system of SAR for
West Bengal. We then move to an exploration of the potential elements of this PS. These
are the potential actors and the potential relationships between, out of which the PS may
be constructed.
6.2 What is supplied?
Conceptualizing from Technology to Utility
hat has been designed by ISWA and can be built and installed by manufacturers is a
technology. On the other side of the supply chain, what the envisaged users of the
technology need is not this hardware but health, or at least a trustworthy supply of
arsenic-free water. In this section, we will explore what lies along this line between
‘technology’ and ‘utility’, in abstract terms but in such a way that they can later be
translated into concrete actors with concrete functions, obligations and remunerations in
the SAR provision system.
The concepts will be arranged concentrically around the technology. The first concept
then is, logically, the technology. With this we refer to the ‘naked’ hardware, installed
and tested in situ, plus a guarantee that the supplier is liable for major, structural
breakdowns. The abstract actor attached to the technology then is the ‘technology
supplier’. Note that for the sake of simplicity, we do not distinguish between different
types of actors here, such as actors specializing in manufacture of subcomponents or
actors specializing in assembly or installation. Our story starts with the technology
supplier as the actor who has installed and tested the machinery in the village and we
assume that he is the one receiving the remuneration in return. Usually when we buy
something of some complexity, it comes with ‘directions of use’. For SAR, this will
certainly of great importance. Irrespective of who will in fact carry out the operation and
W
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maintenance, transferring the knowledge of how to do so will require more than just a
piece of paper. This brings us to the concept of ‘extended technology’. The extended
technology is here defined as the technology plus the provision of the necessary
knowledge and tools for operation and non-structural maintenance and repair. The
certification and quality check will be delivered separately by a specialized provider.
The concentric arrangement of the two concepts now defined requires that we
distinguish between inclusive and specialized providers. This is because actors can either
supply the extended technology (i.e. the technology plus the knowledge) or specialize in
supply of only the additional element, in this case, the knowledge. In other words, there
may either be one ‘extended technology supplier’, or a ‘technology supplier’ plus a
‘knowledge extension supplier’. Both structures may be effective, and both can be
conceptualized this way. The certifier and the quality check provider will always
specialized, never inclusive. Thus, when anybody buys the technology, it has to be
certified: the buyer needs to be sure that the technology is working. Besides, the
certification and quality check need to be carried out on a regular basis because the
technology may break down, and this risk is especially high in the rural localities in
developing countries. Decisions have to be made on the period covered by the
certification. How often needs the water to be checked on the arsenic content? This is
dependent on the scale of the technology (whether it supplies water for a whole village or
only for one household). It is also dependent on the local characteristics of the soils.
During monsoon, for instance, the water table fluctuates which might influence the
arsenic content in the water provided by the technology, because the absorption zone
might change. Research is conducted to answer this question. Thus, depending on the
circumstances, scientific experts should decide in co-operation with the local experts on
the term necessary for certification. Local experts, such as in our case Panchayat pradhan
or Panchayat members, have to be involved in this issue, because they have knowledge
on the local situation and what the local people think would be trustworthy enough.
Certification cannot be done by the same agency as the one providing the operational
technology. Blending different interest in one agency is not trustworthy. What are then
the qualities a certifying agency should have? First of all, the agency should be an
independent institute, independent of any funding from firms that might be involved in
the production of the operational technology. Preferably, the organisation should be non-
profit, so that there the chances for bribing are the smallest. The second prerequisite is
that the organisation is scientific trustworthy. In practice, it would be best if the
organisation has a good name in society. After this little detour, we return again at the
technology and its forms that can be envisioned. We keep up the distinction between
inclusive and specialized suppliers in the rest of the exploration.
Next on the ladder is the operational technology. This is defined as the technology
working, and kept on working, in the way it is meant to. This may be achieved by an
inclusive actor (then to be called ‘operational technology supplier’), or by adding a
specialized actor (‘operation supplier’) to the preceding rung. The operational technology
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also includes the certification and quality check. All three provision stages defined up
till now work on what may be called the input side of the production of arsenic-free
water. The thing-to-be-supplied can also be defined on the output side, however, which
in our case is the arsenic-free water itself. This is not necessarily the same as supplying
utility, because utility could also be defined further along the causal chain, e.g. as health.
This would not be practical in our case, because health depends on so many more factors
and actors. Therefore, we define arsenic-free water as the end of the supply chain.
Arsenic-free water is the utility. Inclusive actors supplying arsenic-free water are the
‘utility suppliers’ in our nomenclature. Theoretically, it is easy to imagine such an actor,
who operates the technology, tests the water for arsenic and then supplies it to the users,
remunerated by any form of compensation method (see below). In practice, it is likely
that users will not trust this all-inclusive actor enough, since the actor is financially
dependent on the water being arsenic-free. Probably, therefore, also one or more
specialized actors may enter the scene here. We may call them ‘utility guarantors’. Recent
trends in society and the literature point at the many advantages of extending the
definition of ‘what is supplied’ in the direction of utility in stead of only the technology.
One example is the shift towards supplying the continuous presence of an up-and-
running vehicle, usually though some form of leasing out, instead of the purchasing of a
car. In more general terms, this is a form called the sale of a performance in a service
economy (EC, 2001). Section 5.5 provides more details.
6.3 Users, Suppliers and ‘Central Actor’
he notion that risks and maintenance may be brought to bear on producers rather
than consumers is of great importance for the arsenic problem. It is of course not
forbidden or impossible that rural households supply maintenance of the technology or
organise water quality control. In our nomenclature, the household is then both user and
a supply actor. They ‘co-produce’. The nomenclature implies, however, that the abstract
‘user’ is defined as the entity using the utility, not the technology. No burdens of risk,
maintenance or any other is implicitly shifted to or expected to any entity called ‘user’.
This, we hope, may help avoid the well-known problem that households are implicitly
expected to co-produce supply elements that they are not motivated or capable to
supply, with failure of the supply as a result. We now have a first notion, however
abstract, of types of possible actors in the supply chain. Theoretically, there need to be
only two types at minimum: one all-inclusive utility supplier and one category of users.
On the other extreme, there may be quite many actors, all specializing in one function,
within the supply chain (see above) or outside it, e.g. as banks or government authorities.
How will all these actors relate to each other? In order to keep this question within
reasonable bounds, we have found it useful to define the ‘central actor’. The central
actor is the actor with the right to distribute the utility (i.e. the arsenic-free water)
directly after its production. The central actor is set as the pivot between suppliers on
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the one side, and the users on the other. With that, the central actor will usually also be
the financial link between users and suppliers. If the central actor remunerates one or
more actors on the supply side for the right to distribute the arsenic-free water, it is
justified (though not necessary) that users remunerate the central actor (see Chapter 1).
In concrete reality, the position of central actor in subsequent sections and chapters may
be taken by a household, a commercial firm, a government agency, and NGO or others.
But before going to that concrete level, we pay attention to the abstract options of types
of relationship between the central actor and the utility users and suppliers.
6.4 The relationship between Central Actor and Users
his section deals with the theoretical dimensions of the relationship between the
central actor and the users. These dimensions are essential and exhaustive. Here, we
first describe the dimensions and its various options per dimension. Then, all the
dimensions may be combined and put in concrete examples. We distinguish four
essential dimensions in the relationship between the central actor and the users. This
concern:
(1) The manner in which the utility (= arsenic free water) is provided,
(2) The manner in which the rights are distributed
(3) The manner in which the obligations are distributed, and
(4) The basis of the remunerations.
Availability of utility
There are basically two ways in which water is available for the users. The first way may
be called batched water. The user has to go to the pump to fetch water before she can
use the water. This implies that the user has to put effort in getting the water. The other
way is that the user has directly access to a continuous water supply system with running
piped water. For this system, the user does not need to put effort in getting the water.
This distinction is essential: people will never batch much more water than they actually
use, while a continuous water flow makes it possible to spill water easily. This could be
resolved by using tap that closes off automatically after, say, 10 seconds.
Distribution of rights
Who has the right to use the utility? There are several options we can think of.
(1) The first one is that the rights are distributed to predefined users. Thus, a certain
group of people are allowed to use the utility.
(2) The second option is that everyone has the right to use the utility.
(3) The third option is also that everyone has the right to use the utility, but arranged
through transferable water rights. Thus, everyone gets rights for a certain amount of
water and is allowed to sell these rights. Transferable generalized water rights may serve
efficiency but equity only to a certain degree, as is explicated in the following example. If
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the system’s capacity would be 10.000 buckets per year, and if there would be 100
households, each household may receive 100 bucket vouchers (this serves equity).
Vouchers may be used or sold at will. Vouchers then will tend to end up with households
most motivated and closest to the well, because people far from the well are not very
interested. There will be no wastage. This will lead to efficiency. At the other side of the
coin, however, we will see that the poor will be inclined to sell, so that health is traded off
for food etc. There are many existing examples concerning transferable rights and
quotas, for instance in irrigation systems where people get a water right per hectare that
they can sell, tradable quota in fisheries, tradable milk quota in the Netherlands, and on a
larger scale the Kyoto protocol.
Distribution of obligations (=payment)
Next to the rights, we have the obligations. The question is: “Who is paying for the
utility?” Again, three options come into being.
(1) Obligations are distributed to users. Thus, the user himself is paying for the use of
the utility.
(2) Obligations are distributed to everyone. This implies that everyone pays for the utility,
independent of whether people use the utility or not. This implies that the utility is paid
for from taxes.
(3) Obligations distributed to specific others. It is possible that others are willing to pay
for the utility, such as NGO’s. Thus, others are subsidizing (part of) the utility. A subsidy
from the government does not fall into this category, since it will be at the expense of
other public goods, unless the government received a specific subsidy to spend on clean
water from the World Bank or some other organisation In practice, it is not necessary that
1, 2, or 3 is taking up the full payment. The payments may be shared between everyone
and the specific other (for instance in the situation where a development organisation is
subsiding and the government fills up the rest).
Basis of remuneration
There are several ways in which the payment can occur.
1. One-off. One purchases the eternal right of utility. The remuneration is then
irrespective of use.
2. By unit of time. The payment is made on a time basis (thus not on the basis of the
amount of utility). Thus, per month for instance, a fixed price is being paid. This case
may be illustrated in the Netherlands, for instance, where some employees that use a
lease car from their boss, may use the car for private purposes (unlimited within the
national border) when paying a friendly fixed percentage of the lease amount per month.
3. By unit of utility. The third manner to remunerate is by unit of utility, i.e., in our case,
the payment for the amount of the arsenic free water that is provided. This kind of
remuneration takes place in the option ‘transferable water rights’ as described in the
dimension on ‘distribution of rights’. The question remains on how to measure the
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amount of water. In line with the first dimension on availability of utility (batched or
piped) it can be measured by
a. Batch. In this way, the payment occurs by bucket taken from the pump or tap.
b. Hours of flow. This resembles the batch payment, but for lack of exact measurement
of litres, people count the time of water flow. In the case of irrigation water this system is
sometimes applied when people pay per hour of water flow.
c. Utility meter. By far the most obvious way to measure the amount of utility is to use a
utility meter, such as a water meter or a park meter.
6.5 The relationship between CA and Suppliers
he relationship between the central actor and the suppliers is essentially a normal
commercial market where actors negotiate over rights and obligations, with
government actors bound by the rules of public procurement. These normal market
relations do not require special attention here. The only point worthy to note is that the
central actor may also lease/hire the operational technology in stead of buying the
extended technology. Leasing and hiring implies that the provider retains the ownership
and the liability. The difference between leasing and hiring is the term of use; i.e. hiring
is on a short-term basis, while leasing is on a long term basis. As described by EC (2001),
leasing is attractive for users, especially because:
• The users do not carry any risk (the risk is with the provider of the operational
technology)
• Minimum own knowledge is necessary
• There is a high motivation from the leasing agent to deliver because the agent gets
paid per unit or performance. Leasing a car is a well known practice. However, leasing
takes place in many other areas as well. In the case of arsenic free water provision,
leasing of the utility would imply that the central actors only pays (e.g. per litre) when the
arsenic-free water is actually supplied and certified.
6.6 Facilitators
n the previous sections, we discussed the role of the suppliers, central actors and
users and their relations. There are important actors outside the supply chain, too.
These we call the facilitators. According to function, we may define:
• Financial facilitators
• Collective action facilitators
• Information facilitators
• Market establishment facilitators.
Financial facilitators
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Implementations of the SAR technology will cost money, so there is a need for financial
facilitators (e.g. banks). If we follow the same way of reasoning as we did in the previous
part of the chapter, we will look at the central actor and its relations wit the suppliers and
the users. As said, the central actor is set as the pivot between suppliers on the one side,
and the users on the other and will usually be the financial link between users and
suppliers. Since we do not pay much attention here to the suppliers, we do not need to
go into deeper detail in the money business on firm level here.
For calculating the cost of the SAR technology systems, a distinction may be made
between capital costs (initial investment) and maintenance costs (yearly returning costs).
In all cases, the costs of the various SAR technology systems will be relatively low,
depending on its size, kind of operation (operational technology or extended
technology), and whether it is a add-on on an existing well or anew system. All
knowledgeable persons in West Bengalese government are convinced that the
government is very willing to promote and to invest in cheap sustainable technology that
provides arsenic free water. We may thus assume that if the government would be the
central actor, it can access sources to buy the technology (initial investment costs)
without much trouble. This may be any governmental bank that is willing to assist in
investments. The payment could also be partly or fully subsidized, either by the
government (i.e. spreading the financial burden as a tax over all citizens) or by a
specialized agent such as NGOs, or a special subsidy by the GO (received from the World
Bank for instance). Financial capacities are different at the level of users. They are the
people that usually do not have much money to spend. Even if the users would be the
central actor and would be able to access sources of funding for initial investments, there
is no direct financial benefit generated by the arsenic free water that may be used to
repay the loan or interest. We may assume that the foregone costs, thus the money that
people would not spend at hospitals due to arsenic related diseases and the costs people
safe by staying healthy and working, are an indirect benefits that should help convince
people to invest. This cost benefit analysis is difficult to make however, in which different
time horizons are weighed in the same calculation. If people are organised in self-help
groups, they have more easily access to financial assistance, because banks are hesitant
to give loans to individuals without collateral but they give loans to self-help groups. If
people from the “below the poverty line” (BPL) group organize in a self-help group, they
receive subsidy from the government. A self-help group must organize meetings at least
once a month and the minutes have to be shown to the bank. All the government banks
have to accept these self-help groups. A 15 to 50 percent of the loan will be repaid by
the GO if you are BPL. The longer the self help group exist (and shows good behaviour in
repayment), the more money the group can borrow from the bank.
Collective action facilitators
In case self-help groups would act as user groups or central actor for arsenic free water,
collective action facilitators could become important. De Groot and Tadepally (2007)
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analysed the relation between collective capital and collective action based on a case
study on village-level irrigation systems. In the Indian state of Andra Pradesh, the
majority of the 73,000 village-level irrigation systems (‘tanks’) are in a serious state of
neglect. Restoration of the tanks is profitable at the community level but unprofitable for
farmers individually. In order to overcome this problem of collective action, farmers must
not only have a positive motivation towards tank restoration, but also have the capacity
to bring this motivation into collective action, i.e. the mutual trust and the institutions
that are often referred to as (collective) social capital. This paper analyses the effect of
the approach of a local NGO that focuses on awareness-raising and advising the
community with the aim to bring about tank restoration sustained by the villagers
themselves. It is found that (pre-existing) collective social capital, as measured through
five simple indicators, strongly correlates with successful tank restoration. Social capital
does not appear to be constructed by the NGO’s activities as such, however; a community
with pre-existing social capital that is too low for tank restoration will fail, irrespective of
the continuation of NGO efforts. Not the NGO efforts but successful collective action
itself adds to collective social capital. It is concluded that development agents that aim to
bring about a specific group-based action should focus on groups with sufficient
collective social capital for that action. Alternatively, development agents that aim to
enhance collective social capital should embrace any collective action that a community is
motivated for and capable of. The facilitator may be a member of the group, or an
outsider that is well respected by the group, or perhaps an NGO. For more information on
specific guidelines for community work on collective action see for instance Allen et al.
(2002). Thus, for identifying possibilities for collective action, it is important to study the
level of collective social capital in a village or the potential user group of the technology.
An assessment of existing social capital, with a focus on self-help group potential, has
been made in our research site.
Information facilitators
Many studies identify a lack of awareness of arsenic contamination among the
stakeholders. The study of Paul (2004) arsenic awareness identified arsenic risk region,
level of education, gender, and age as important determinants of arsenic knowledge. The
findings of this study will aid in making existing health education programs more
effective and in reducing the risk of developing arsenic-related illnesses. The World Bank
(2005) emphasizes that awareness should also explicitly include information on what
arsenic is not; arsenic pollution is not contagious and arsenic is not a germ that dies
when boiled. Besides, it should be made clear that while turbid surface water is unsafe,
some clear groundwater can also be contaminated (ibid.). Hossain et al. (2005) conclude
their paper concerning the ineffectiveness of arsenic removal plants with a call for
education “for the villagers about the existence, magnitude, danger and symptoms of the
arsenic problems ….. Training them on issues of water management and involving the
whole community in the maintenance of their water source”.
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Furthermore, the provision of information is of the essence for any technology to work. In
well-established delivery systems, information is often provided by the involved market
parties (sometimes regulated to some extent by government regulations to prevent
unfounded claims or force the provision of information on risks etc.). In cases in which
the government takes a special interest because of the large collective level risks (e.g.
smoking) or benefits (e.g. arsenic technology, solar technology), public or semi-public
bodies may be assigned to information provision to the public or market parties,
especially in the early phases when a delivery system is not well formed yet. Such bodies
may also be helpful in organising the market (without themselves becoming market
parties, see next section).
Market establishment facilitators
Markets work through trust and routines. Trust takes care of that actors do not need
enormous amounts of time and energy to get all details of deals on paper and check
upon each other’s behaviour. Routines, examples of which are standard contracts and the
unwritten expectations that new transactions will essentially be carried out as were the
previous ones, serve the same purpose of low transaction cost. New delivery systems on
new markets are therefore sometimes hard to establish. Actors that have not worked
together yet will start out with low levels of trust in their relationship. It is even possible
that for some actors, the whole job of building trust is just too energy-consuming and
risky to make it seem worthwhile to start the relationship at all. In such a case, a delivery
system may fail to come into being in spite of a potential match between supply and
demand. The same holds for the routines, especially for small actors such as individual
households, self-help groups or small local contractors. Small actors such as those rely
much on standard contracts, lacking as they do to think out and put on paper all the
possible ramifications of the new technology and the new relationships. (In some cases,
small actors may piggyback on a few larger ones that have established market routines
as first movers.) Sometimes, new markets may arise smoothly especially when the new
technology is not too different from an existing one and actors that already trust each
other through previous transactions come together and use existing routines to get the
new delivery system in motion. This phenomenon is particularly helpful in mixed cases
that only partly consist of really new elements. In fact, SAR may offer an example here,
since much of it consists of standard drinking water supply techniques and is already
built locally by existing contractors in the model village. If panchayats would be central
actors for SAR and if panchayats are already used to work with this type of contractors
(e.g. for basic water supply), this could become the core structure around which the
other, new elements in the delivery system, e.g. the water quality assurance, could be
built.
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7
Operation & Maintenance Issues
7.1 Operation
7.2 Maintenance
7.3 Certification
7.4 Delivery System
7.1 Operation:
or the absorption to work in the soil, the recharge needs only be done on a volume
basis. If recharge would then be necessary only once every month or so, this may
entail the risk that the absorption zone could become overloaded by arsenic arriving in it
due to overall groundwater flow. It might therefore be safer to recharge at least once
every week, irrespective of withdrawn volumes. The operation of this system is simple. It
can be automatic or manual, both with an electric pump.
Automatic operation:
Automatic operation is run by a sensor in the recharge tank, for instance, that identifies
when the tank is full and when the tank is empty. The cycle is as follows:
(1) Overflow of recharge tank starts or sensor turns to ‘full’,
(2) Well is disconnected from the supply tank
(3) 2 m3 of water of the recharge tank is emptied back into to well
(4) Recharge tank empty (sensor)
(5) Wait one hour,
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(6) Reconnect the well and supply tank.
Thus, when the sensor indicates that the recharge tank is full, the well is disconnected
from the supply tank and recharge starts. When sensor indicates that recharge tank is
empty, the system waits one hour and then reconnects the well and supply tank. During
the recharge cycle, water can still be used from the storage tank.
Manual operation:
Manual operation can be done when the overflow starts (there is some spare water in the
supply tank) or users may chose to do it every day or every other day, but at least once
every week. Manual operation may be done without sensor because the overflow of the
recharge tank should is easy to spot and hear. The cycle is as follows:
(1) Overflow starts,
(2) Pump is disconnected from power
(3) Empty 2 m3 of water of the recharge tank
(4) Close valve of recharge pipe,
(5) Wait one hour,
(6) Reconnect pump.
7.2 Maintenance
• The maintenance of the T6000 includes the cleaning of the tank every now and then,
because some sediment may accumulate in the tank. The job can be done by any
knowledgeable person. There are cleaning pipes, through which the waste water can be
disposed of.
• The valves need to be checked every once in a while and repaired when necessary.
• The showerheads need to be cleaned regularly, since the aeration is of crucial
importance.
• The pump is to be maintained according to its directions of use.
7.3 Certification
ertification is necessary. The water needs to meet the Indian standards & WHO
standard for drinking water “as desirable and tolerable”. Preferably, people buy the
technology with a certification of the water meeting the standards. This implies that the
plant is has been working for at least a month already, which is the time needed for the
absorption zone to build up. It is important that the certification will be renewed, say
every half year. There should therefore be an easily accessible certifying agency to do the
measurement at low cost.
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7.4 Delivery system of the T6000L
e start with the potential Central Actors for the T6000, followed by the description
of the filling in of the essential dimensions in the relationship between the central
actor and the users.
Central Actor of T6000
If T6000 is put on a daily cycle, it can supply 60 households with 100 l day. T6000 may
therefore be interesting for a group of households (10 or 20 households) or an institution
that wants to be of good service to the neighbours (schools, hospitals or government), or
a single household that wants to make some business in selling of clean water.
If Central Actor buys T6000
• CA buys extended technology (= technology plus the knowledge and tools for
operation and non-structural maintenance and repair) + initial quality assurance
certificate from an independent institute. (Initial utility)
• Operation and daily maintenance (cleaning): by household or other well
knowing/trained person.
• Non-daily maintenance: done or organised by CA. It is such a basic technology that he
buyer can organise it by himself. If wanted, a technology check subscription can come
along with a quality check subscription.
• Quality check (including technology check): quality check (including technology
check-up) subscription when buying the initial utility or later
Or, Panchayat offers water quality check (including technology checkup)
• Who has right to use? CA may give or sell to others
• Who is paying (obligations)?
CA,
and/or (partly) everyone (by subsidy resulting in tax raise),
and/or (partly) specific other (such as NGO or MLA)
• Remuneration
One-off, except for the quality check subscription.
• Who is paying (obligations)?
• CA,
• and/or (partly) everyone (by subsidy resulting by tax raise),
• and/or (partly) specific other (such as NGO)
• Remuneration: Per unit of time, for instance per month.
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8
The Results
8.1 Data generated during Operation
8.1.1 Merudandi, Basirhat
8.1.2 Tepul, Gobardanga
8.1.3 Purbapara, Basirhat
8.1.4 Rangapur, Nilgunj
8.1.5 Ghetugachi, Chakdaha
8.1.6 DO, Conductivity & pH
8.2 Discussion
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8.1 Data generated during Operation
8.1.1 Results of Merudandi, Basirhat
Variation of Arsenic conc at Merudandi, Basirhat
0
0.05
0.1
0.15
0.2
0.25
0.3
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 51 53 55 57 59 61 63 65
Days (1 unit = 2 days)
Co
nc (
mg
/lt)
Actual conc
WHO limit
Indian MPL
Variation of Iron conc at Merudandi, Basirhat
0
0.5
1
1.5
2
2.5
3
3.5
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 51 53 55 57 59 61 63 65
Days (1 unit = 2 days)
Co
nc (
mg
/lt)
Actual conc
Safe limit
Arsenic - WHO guideline 0.01 mg/lt
Arsenic - Indian MPL 0.05 mg/lt
Iron - Safe Limit 1.00 mg/lt
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8.1.2 Results of Tepul, Gobardanga
Variation of Arsenic conc at Tepul, Gobardanga
0
0.02
0.04
0.06
0.08
0.1
0.12
0.14
0.16
0.18
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27
Days (1 unit = 2 days)
Co
nc (
mg
/lt)
Actual Conc
WHO limit
Indian MPL
Variation of Iron at Tepul, Gobardanga
0
0.5
1
1.5
2
2.5
3
3.5
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27
Days (1 unit = 2 days)
Co
nc (
mg
/lt)
Actual conc
Safe limit
Arsenic - WHO guideline 0.01 mg/lt
Arsenic - Indian MPL 0.05 mg/lt
Iron - Safe Limit 1.00 mg/lt
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8.1.3 Results of Purbapara, Basirhat
Variation of Arsenic conc at Purbapara, Basirhat
0
0.02
0.04
0.06
0.08
0.1
0.12
0.14
0.16
0.18
0.2
1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52 55 58 61 64 67 70 73
Days (1 unit = 2 days)
Co
nc (
mg
/lt)
Actual conc
WHO limit
Indian MPL
Variation of Iron conc at Purbapara, Basirhat
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52 55 58 61 64 67 70 73
Days (1 unit = 2 days)
Co
nc
(m
g/lt)
Actual conc
Safe limit
Arsenic - WHO guideline 0.01 mg/lt
Arsenic - Indian MPL 0.05 mg/lt
Iron - Safe Limit 1.00 mg/lt
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8.1.4 Results of Rangapur, Nilgunj
Variation of Arsenic at Rangapur, Nilgunj
0
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
0.1
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
Days (1 unit = 2 days)
Co
nc (
mg
/lt)
Actual Conc
WHO limit
Indian MPL
Variation of Iron conc at Rangapur, Nilgunj
0
0.5
1
1.5
2
2.5
3
3.5
4
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29
Days (1 unit = 2 days)
Co
nc (
mg
/lt)
Actual Conc
Safe Limit
Arsenic - WHO guideline 0.01 mg/lt
Arsenic - Indian MPL 0.05 mg/lt
Iron - Safe Limit 1.00 mg/lt
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8.1.5 Results of Ghetugachi, Chakdaha:
Variation of Iron Conc at Ghetugachi, Chakdah
0
0.5
1
1.5
2
2.5
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28
Day (I unit = 2 days)
Co
nc (
mg
/lt)
Actual Conc
Safe limit
Variation of Arsenic conc at Ghetugachi, Chakdaha
0
0.05
0.1
0.15
0.2
0.25
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32
Day (I unit = 2 days)
Co
nc (
mg
/lt)
Actual Conc
WHO limit
Indian MPL
Arsenic - WHO guideline 0.01 mg/lt
Arsenic - Indian MPL 0.05 mg/lt
Iron - Safe Limit 1.00 mg/lt
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8.1.6 DO, pH and Conductivity values in the plants:
Site Dissolved
Oxygen (ppm)
Conductivity
(mS/cm) pH
Naihati Purbapara,
Basirhat 1.6 – 3.6 1.8 – 2.9 7.06 – 7.6
Merudandi,
Basirhat 2.4 – 3.6 1.48 – 1.9 7.17 – 7.7
Rangapur, Nilgunj 3.2 – 3.6 0.78 – 1.1 7.29 – 7.38
Tepul, Gobardanga 4.6 – 5.2 1.1 – 1.5 7.19 - 7.28
Gotra, Ghetugachi 3.7 – 4.4 0.8 – 1.2 7.25 – 7.7
The detailed values are not provided for DO, conductivity & pH since these tend to vary
within the given limit throughout the monitoring period without any pattern.
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8.2 Discussion
1. The project team could regularly analyze the water quality from 5 plants. The
plant at Naserkul, Ranaghat could not be monitored as intensely like the other
ones, only periodic monitoring was done to ensure safety.
2. A fabulous synchronization is observed between the variation of arsenic & iron
concentrations of the plant water with the advancements of operation. The pair of
graphs, in case of all the 5 plants are seen to follow almost exact pattern
throughout the length of the operational cycles.
3. In case of all the 5 plants, the arsenic concentration is seen to come below Indian
standard Concentration (0.05 mg/lt) within 25 days approximately while it gets
reduced below WHO level (0.01 mg/lt) within 45 – 50 days.
4. The arsenic concentration depends totally on the iron concentration. Arresting
iron will automatically reduce the arsenic. This is due to the co-precipitation of
arsenic (+5) with iron (+3).
5. Arsenic co-precipitates only when it gets converted to +5 state from the soluble
+3 state. But this conversion takes place by enzymatic reaction of various aerobic
microbes. But the project team could not study the exact mechanism of the
enzymatic reaction & the strains of arsenic oxidizing microbes as this study was
out of the scope of the project. In future, this study will most obviously help in
increasing the efficiency of the plants.
6. Once the arsenic & iron concentrations went below the safe limits, it seldom
increased beyond the safe level. Very slight fluctuation is observed in the arsenic
level depending on season (rainfall, etc) and extent of plant activity (hampering of
plant functioning due to long holidays). Thus a very high consistency is noticed in
the plant activity. The oxydation zone is probably spreading in the aquifer, thus
arresting all the arsenic in its reach. This oxidation zone has to be maintained by
regularly recharging the oxidized water.
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9
Conclusion & Recommendations
ome conclusions and recommendations that we reached at after conducting the
project is given below.
1. The functional parts of the plants are performing very well. The results are actually
beyond the expectations of the researchers. The technology is working wonders by
reducing arsenic level from 0.2 mg/lt to BDL (0.002 mg/lt) within 45 – 50 days
approximately. And the main thing is that, this effect is permanent. With continued
functioning, the levels of iron & arsenic are not fluctuating and a consistent pattern is
observed in the working. No chemicals are used here and no toxic wastes are generated.
So there is no question of recharging the chemicals or disposal of wastes, thereby
reducing the O&M costs.
2. RKVM has completed the project within one & half years of working period. It was
estimated in the project proposal that the communities will bear the O&M cost at the end
of the project i.e. two years. Actually, the people have to grow the habit of paying a fee
for the service they are using (whatever nominal the fee may be). This takes a little time.
For now, RKVM is going to look after these plants and pay the electric bills worth a few
dollars per month. A section of the community has started paying up for the water and
the number is growing. RKVM is keeping a close watch on the matter & will transfer these
plants to the community once they become self sufficient.
3. According to the data generated, the arsenic concentration has been significantly
reduced in all of the treatment plants. This reduction in the arsenic content in the
drinking water leads to a significant reduction in the daily arsenic intake from 415 µg i-
S
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As/day down to 140 µg i-As/day. The Tolerable Daily Intake (TDI) for arsenic could be
established at 124 µg i-As/day (Signes-Pastor et al., 2008; Signes et al., 2008c). In this
way, the reduction in the arsenic concentration caused by the in-situ treatment of
subterranean water led to levels very close to those values recommended by the World
Health Organization (WHO). Universidad Miguel Hernandez, Spain has prepared an Excel
file to easily calculate the effect of arsenic concentration on drinking water on the final
daily intake of this metalloid. The user will introduce the arsenic concentration (in µg/L)
and the calculator will give the values of the daily arsenic intake for three different
scenarios (minimum, mean and maximum food availability).
4. There is a very high scope of research regarding the mechanism of the arsenic removal
& the microbial process going down in the aquifer. The spread of oxydation zone & the
recharge period, timing, volume ratio, etc also can be worked upon. A very high level of
interest has been generated among the villagers. They are very much excited about the
sustained success of the plants in removing arsenic, unlike other methods which
generate very good quality water for a few weeks and then starts to stain the pipes with
yellow iron oxide deposits indicating that they have stopped working. (The thumb rule is
that, you remove iron, and then you will automatically remove arsenic). Many petitions
have been submitted at the project office seeking the installation of more of these plants
in different areas of Nadia & N 24 Parganas.
5. Some recommendations about the reduction of arsenic intake through food have been
provided by the UMH, Spain. These are discussed below:
Peeling of tubers and roots: The first recommendation is that vegetables such as turnip,
radishes, potatoes, carrots, etc. should always be peeled before consumption. An
important percentage of the arsenic is highly attached to the outer skin of these tubers or
roots. By peeling potatoes, carrots, etc the daily arsenic intake will be reduced
(Carbonell-Barrachina et al., 1999).
Rice dehusking: Depending on the quality of the water available for rice dehusking,
Signes et al. (2008b) has recommended using the dry or wet processes. If arsenic-free
water (o water with low arsenic content) is available the wet process leading to boiled rice
is recommended; however, if only arsenic-polluted water is available the recommended
method is the dry one, which leads to atab rice.
Rice cooking: Signes-Pastor et al. (2008) and Signes et al. (2008c) has tested three
different cooking methods for rice and these authors recommended the use of the
traditional method in which raw rice is washed until the washings become clear (five to
six times), the washings are discarded and then the rice is boiled in excess water (five to
six times the weight of the raw rice) until cooked, finally discarding the remaining water
(discarded water) by tilting the pan against the lid before serving the rice.
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6. To remove arsenic from the irrigation water, massive upscale of these plants are
needed. Much larger plants can be easily designed & installed for producing arsenic free
irrigation water stored in aerated reservoirs.
7. This technology can be replicated in almost every arsenic affected area of West Bengal
due to high concentration of iron in groundwater, easy availability of electricity & high
level of awareness. RKVM has a very strong presence in the districts of Nadia, N 24
Parganas, Kolkata and S 24 Parganas and here it can itself replicate these projects in no
time at all. In the districts of Burdwan, Howrah, Malda & Murshidabad, RKVM can tie up
with other NGOs working in those areas to reach out to the people in a much larger scale.
8. Alternate source of generating revenue for O&M purpose: RKVM is a charitable
organization & is able to mobilize enough resource to sustain the operation of these
plants for years to come through charity and donations. For example, any person or
company can sponsor the drinking water for a whole village community by paying a
minimum of Rs 100.00 (2 USD) per month. Given the fact that RKVM has a very high
position of trust among the people and has thousands of devotees & members, such type
of donation and support will be easily available if required at all. After all, the O&M is not
at all expensive.
The Subterranean Arsenic Removal (SAR) Technology has every potential for
revolutionizing man’s war against Arsenic. It is highly suitable for running in the rural
environment due to its simple mechanism & locally available spare parts & easy
maintenance systems. The running cost is also very low, making it fit for low income
communities. A central actor like Panchayat or Self-help groups will be most suitable
Central Actor to run it.
Prevention is always better than cure. So it is much better to prevent the arsenic from
emerging on the surface by treating the whole aquifer to produce safe water rather than
treating the unsafe water using costly chemicals after bringing it out on the surface and
exposing the community to the hazard of the toxic waste.
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10
The Photographs
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11
The Annexure
I. Manuals & Questionnaires
II. Agreements, Certificate & Technology Transfer letter
III. Persons associated with DM 06-880
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Annexure - I
Manuals & Questionnaires
Subterranean Arsenic Removal: Experiment to Delivery
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Subterranean Arsenic Removal: Experiment to Delivery
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DETERMINATION OF IRON
Reagents:
1. Conc. HCl
2. Hydroxylamine Hydrochloride: Dissolve 10 g NH4OH.HCl in 100 ml water.
3. Ammonium Acetate Buffer Solution: Dissolve 250 g NH4C2H3O2 in 150 ml water.
Then we add 700 ml of Glacial Acetic Acid.
4. Phenanthroline Solution: Dissolve 100 mg of 1-10 phenanthroline monohydrate in
100 ml water by stirring and heating to 80 oC.
5. KMnO4(0.1M): Dissolve 0.316 g KMnO4 in water and dilute to 100 ml.
6. Stock Iron Solution: Slowly add 20 ml Conc. Sulfuric acid to 50 ml waster and
dissolve 1.404 g ferrous ammonium sulfate . Add 0.1 N KMnO4 dropwise until a
faint pink colour appears. Dilute it to 1000 ml with water and mix.
7. Standard Iron Solution: Pipette out 50 ml stock solution into a 1000 ml volumetric
flask and dilute to mark . 1 ml =10 µg Fe
Procedure:
50 ml sample+ 2 ml conc HCl + 1 ml Hydroxyl Amine solution+ few glass beads and heat to
boil to half of the volume. Cool it and then transfer it to 50/100 ml volumetric flask. Add 10
ml ammonium acetate buffer solution and 4 ml phenanthroline solution and dilute to mark
with water . Mix properly and allow a minimum of 10 minutes for maximum colour
development. Read the wavelength in spectrophotometer at 510 nm wavelength.
From the standard curve, determine the concentration of iron in this unknown sample.
Subterranean Arsenic Removal: Experiment to Delivery
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DETERMINATION OF ARSENIC
Reagents:
1. Conc.HCl
2. Potassium Iodide Solution:
15 g of KI was dissolved in 100 ml distilled water and stored in a brown bottle.
3. Stannous Chloride Solution:
40 g of SnCl2.2H20 was dissolved in 100 ml conc HCl.- this is correct.
4. Lead Acetate Solution:
10 g of lead acetate was dissolved in distilled waster to prepare 100 ml solution.
5. Silver Diethyl Dithiocarbamate:
0.5 g of SDDC dissolved in 100 ml of Pyridine.
6. Zinc Granulated
7. Standard Arsenic Solution (1 ml=1 µg As): 1.32 g of As was dissolved in 10 ml of distilled
water having 4 g of NaOH and make up the volume to 1 litre. This was 1000 mg/lit stock
solution containing 10 µg As in 1 ml. This was diluted further 10 times to prepare standard
solution of Arsenic.
(1 ml=1µg of As)
Procedure:
1.35 ml sample + 5 ml conc HCl+ 2 ml KI + 8 drops of SnCl2. Thoroughly mixed and kept
for 5 minutes. The glass wool in the scrubber was soaked with lead acetate solution taking
care that solution should not drain into the generator.. 4 ml of SDDC was taken in the
absorber tube. 3 g of Zn was added in the generator and immediately the assembly was
connected air tight. It was kept for about 30 minutes for the generation of AsH3 with slight
heating. The gas was absorbed in SDDC in the absorber tube and the colour changes to red.
The intensity of the colour was measured to 535 nm using the reagent blank as reference.
A graph between the absorbance (OD value) and the concentration which is the standard
curve was prepared.
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Operator’s log book
Record of Groundwater during Sampling
Plant Name and Code
Operator
Test report No.
Cycle No.
Sampling Point
Sample Label
Time Water Meter Reading (lit)
Weather Air Temperature [Deg C]
Colour Electro Conductivity [us/cm]
Turbidity pH Value
Smell Dissolved Oxygen [mg/l]
Water Temperature
Sediments Yes O No O Floatable Yes O No O
Frothing Yes O No O Striae Yes O No O
Sample conservation (see label)
Arsenic [mg/l]
Iron [mg/l]
Date of sample delivery to lab.
Pump Started at
Overflow Started at
Pump Stopped at
Intermision From ………………. to ……………
Water meter reading before Infiltration
Infiltration started at
Water meter reading after Infiltration
Signature of the operator: Date:
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Socio-economic & WTP Questionnaire
Questionnaire Choices
Example of response
1 What is the
household size? 6-8
2 Age of the
persons staying 0-10 10-20 20-30 30-60 >60 12-70
3
How you are
getting the water
?
Municipal
ity tap
water
Tubewe
ll
Water
Truck Time-call Other
Deep-tubewell
(depth 300ft- 3
times a day; if
unavailable,
then nearby
community
centre
4
How much water
they are
procuring for
cooking and
drinking (in
buckets) daily?
5 10 15 20 >20
5
How much you
are paying for it
(Rs)?
Nil 10 20 30
6
What is the time
required for
procuring the
water ?
0-1/2 HR ½ hour-
1 hour
1 hour –
2 hours > 2 hours
7 Who brings the
water?
House-
wife maid Others
8
How many
earning members
in the family?
1 2 3 >3 2
9 What is their
profession? farmer
salaried
job Business Day labour other school work
10 Who is the head
of the family?
Responde
nt husband Wife Parents father
11 Is it own house or Own Rented own
Subterranean Arsenic Removal: Experiment to Delivery
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rented
possession?
12 What is the rent
you are paying ? 10-100
100-
500
500-
1000 >1000
not
paying na
13
Whats is the total
earning of the
family ?
0-3000 3000-
6000
6000-
12000
12000-
20000 >20000 3000-6000
14 How much you
are spending ? 0-3000
3000-
6000
6000-
12000
12000-
20000 >20000 3000-6000
15
What is the
education of the
decision maker of
the family?
School /
HS Graduate
Post
Graduate
No
education no
16
How is the health
condition of the
family members?
Not good good very good Bad ok
17
If health
condition not
good, why is it
so?
Money Food Water Other food, money
18
Are you happy
with the quality
of water?
Good Bad No idea no idea
19
Are you happy
with the quantity
of water?
Yes No No idea yes
19
Do you know
about arsenic in
water and how it
affects you?
Yes No little No idea no
20
If RKVM supplies
good quality
water, would you
go for the same
or prefer to
continue with the
existing system ?
Yes No No idea yes
21 If the water is not
free, would you Yes No No idea may be
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pay ?
22 Would you like to
pay Rs10/month? Yes No No idea don’t know
23 Per month would
you pay Rs 20? Yes No No idea
24 Per month would
you pay Rs 30? Yes No No idea
25 Per month would
you pay Rs 40? Yes No No idea
Questionnaire
Need for water
Household size
Consumption
How they are using the water
Existing arrangement of house for getting water
How they are getting the water ( private source/vendors/self)
Time required
Available labour in case water is to be procured and need to be collected from distant place
Adult woman
Children
Ability to pay
House hold exp
No of earning member
Person working as farmer or outside job
Value of house
Owned/Rented
Quality/Quantity
Quality OK
Quantity OK
Personal characteristic of the house
Age of household head
Age of other members
Education
Occupation
Sex ratio
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Children
Awareness of people in the house about arsenic problem
Health condition of the family
Is they receive any special treatment for any illness or health
Household attitude
External exposure to the world
Awareness of quality of water for health
Who they think should provide water
What they feel about water should be priced or not
Satisfaction with the existing water supply quality and qauntity
Other factors
Distance of the village from the district head quarter
Proximity of the village from perennial water source
WTP
Are they willing to pay for the water?
How much they are paying now?
Bidding game
Cost for cooking and drinking only?
For costing calculation what are needed?
Running cost
Maintenance cost
Depreciation
Interest on capital
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Food Safety Questionnaire
24h-RECALL QUESTIONNAIRE - I
Hi, good morning, would you mind to answer a couple of questions dealing with your food
habits. It only will take 5 minutes.
Name:
Gender:
Age:
1. What (did) do you generally take for breakfast, (yesterday)?
Following questions depending on the answer:
1.1. How many or much…….?
1.2. What was its size?
1.3. How did you take it: raw, cooked, …?
2. Did you take anything in between the breakfast and the lunch?
Following questions depending on the answer:
3.1. How many or much…….?
3.2. What was its size?
3.3. How did you take it: raw, cooked, …?
3. What did you take for lunch, yesterday?
Following questions depending on the answer:
3.1. How many or much…….?
3.2. What was its size?
3.3. How did you take it: raw, cooked, …?
4. Did you take anything in between the lunch and the dinner?
Following questions depending on the answer:
4.1. How many or much…….?
4.2. What was its size?
4.3. How did you take it: raw, cooked, …?
5. What did you take for dinner, yesterday?
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Following questions depending on the answer:
5.1. How many or much…….?
5.2. What was its size?
5.3. How did you take it: raw, cooked, …?
6. How much water did you normally drink every day?
7. How many cups of tea do you regularly drink every day? 8. Do you always eat at home? (Just considering that especially some of the males may work at the city where non-polluted water is available) 9. Do you smoke? If yes, how many or at what frequency in a day? 10. Do you think that your parents ate better food? If so, how? 11. Do you think that your children eat well? What do they eat? 12. Does a girl child receive better nutrition? If so, how?
THANK YOU VERY MUCH FOR ANSWERING OUR QUESTIONS!
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QUESTIONNAIRE - II
Hi, good morning, would you mind to answer a couple of questions dealing with your
food habits. It only will take 5 minutes.
Name:
Gender:
Age:
1. Are you the mother of the house? If the answer is not, the questionnaire is finished.
2. Are you the person responsible for collecting the water and preparing the meals? If
the answer is not, the questionnaire is finished.
3. How many people are there in your household?
4. Where do you get the water for drinking and food preparation?
5. How many times do you get water from this place in a daily basis?
6. How much water do you carry in a single trip to this place?
7. How do you store the water in your household?
8. Where do you get the food for your meals?
9. How much water do you use for preparing your main meals?
THANK YOU VERY MUCH FOR ANSWERING OUR QUESTIONS!
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ANNEXURE – II
Original Grant Agreement with the World Bank dated 3rd April, 2007
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Amended Grant Agreement with the World Bank dated 18th March, 2008
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Amended Milestones and Payments Schedule (Annex B of Project Agreement)
Project title: Subterranean Arsenic Removal – From Experiment to Delivery Project No.: 00880
Mile-
stone
Due Date Activities/Output
0 00/04/07 Signing the Contract:
Discuss and agree on the milestone objectives with the Project Liaison
Project Agreement Signed by the Project Team, Project Partner, and
the World Bank Country Director
First Payment (25 % of Total): $ 50,000
1 00/07/07 Milestone 1:
• Review previous studies and consultation with experts
• Baseline survey in the villages (population and socio-economic
demography, food habit, water intake, farming practice, water
quality)
• Finalizing location to design plant configuration
• Installing plant in two locations
Organizational plan:
• Appointment of Researchers (2)
• Appointment of Surveyors, office staff, lab assistant, security
• Conducting one meeting with all the partners
• Setting up test laboratories
• Providing vehicle
• Installation of audio-visual aid for regular conference
• Setting up office with computers and other accessories
Submit 1st standard DM progress report to Project Liaison and DM
Contact
Second Payment (25 % of Total): $ 50,000
2 00/11/07 Milestone 2:
• Installation of plant in four locations
• Monitoring the same for water quality and for food chain
Organizational plan:
• Appointment of supervisors and one researcher
• ISWA will visit the place of installation and will provide
necessary suggestions and modifications
• System will be computerized and all operations and test results
are recorded
Submit 2nd standard DM progress report to Project Liaison and DM
Contact
Third Payment (20 % of Total): $40,000
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3 00/04/08 Milestone 3:
• Monitoring of water quality and food chain will be continued • Evaluation by consultants and researchers for sustainability • Operation and maintenance of all the plants by providing
operators, securities and researchers • Compilation and collation of data for preparing plant manual Organizational Plan:
• Preparation of report on contamination of arsenic in food chain
• Consultation with UMH being stationed in India for
finalizing the report Submit 3rd standard DM progress report to Project Liaison and DM Contact
Fourth Payment (20 % of Total): $ 40,000
4 00/09/08 Milestone 4: • Sustainability and water quantity requirement analysis • Follow-up the villagers for training for operation and
maintenance • Conducting awareness generation program at the grass root
level in the village • Interaction with the stakeholders for further implementation • Developing Public relation and expanding knowledge and
education • Preparation of final report and project manual Organizational plan:
• Meeting with all the partners • Finalization of the report and manual
• Distribution of manuals to the stakeholders Submit 4th standard DM progress report to Project Liaison and DM Contact
Final Payment (10 % of Total): $20,000
Final Report within 3 Months of the Final Payment
Submit Project Completion Report and hold a Completion Interview with Project Liaison
TOTAL PAYMENT $ 200,000 (100%)
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The World Bank Development Marketplace Certificate of Recognition
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Technology Transfer Letter
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Copies of Certificates of the National Awards
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ANNEXURE - III
Persons associated with the DM 06-880
Swami Nityananda Secretary, RKVM
Soumyadeep Mukherjee Project Team Leader
Dr. Bhaskar Sen Gupta Chief Advisor
Prof. Carsten Meyer Technical Advisor
Prof. Angel A. Carbonell Barrachina Food Safety Advisor
Prof. Wouter de Groot Delivery System Advisor
Indrajit Bera Research Assistant
Krishnendu Halder Research Assistant
Prabir Saha Asst. to Team Leader
Debangshu Dutta Civil Engineer
Sanjoy Basak Surveyor cum Lab Assistant
Partha Saha Computer Accountant
Kanti Bandopadhyay Accountant, RKVM
Sandip Mondal Cashier, RKVM
Dhiraj Chakraborty Cashier, RKVM-IAS
Gobinda Maity Senior Operator cum Supervisor
Shibsindhu Mondal Operator cum Supervisor
Alok Baidya Operator cum Supervisor
Biswajit Sinha Operator cum Supervisor
Tapan Mallick Operator cum Supervisor
Subrata Biswas Operator cum Supervisor
Shantinath Bandopadhyay Driver
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Ramakrishna Vivekananda Mission, Barrackpore 114
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*****
Subterranean Arsenic Removal: Experiment to Delivery
Ramakrishna Vivekananda Mission, Barrackpore 117
Contact Information:
Project website: www.insituarsenic.org
Swami Nityananda Secretary
Ramakrishna Vivekananda Mission,
7, Riverside Road,
Barrackpore: 700 120
West Bengal, INDIA
Office: +91 033 2592 0547
Fax: +91 033 2560 6904
Website: www.rkvm.org
Email: [email protected]
Dr. Bhaskar Sen Gupta Chief Advisor, DM 06 - 880
Dept of Environmental Engineering,
Queen’s University, Belfast, UK
Office: +44 78461 12581
Email: [email protected]
Soumyadeep Mukherjee, M.Sc
Project Team Leader, DM 06-880
RKVM-IAS,
3, B.T. Road, Agarpara,
Kolkata: 700 058,
West Bengal, INDIA
M.Tech student
School of Safety & Occupational Health Engg
Bengal Engineering and Science University, Shibpur
Howrah, West Bengal, INDIA
Office: +91 033 2583 9580
Fax: +91 033 2563 7302
Mobile: +91 94337 16340
Email: [email protected]
Prof. Dr. Ángel A. Carbonell-Barrachina
Food Safety Advisor, DM 06-880
AgroFood Technology Department
Miguel Hernández University
Ctra. Beniel, km 3.2
03312-Orihuela, Alicante
SPAIN
Office: +34.966.749.754
Fax: +34.966.749.677
Mobile: +34.605.302.372
Email: [email protected]
Prof. Dr. Wouter T. de Groot Delivery System Advisor, DM 06-880
Institute of Environmental Sciences (CML)
P.O.Box 9518
2300 RA Leiden
The Netherlands
Email: [email protected]
Prof Carsten Meyer Technical Advisor, DM 06-880
ISWA, Stuttgart University
Germany
Email: [email protected]