Grantee Research Project Results
Final Report: Arsenic Removal and Ecologically Safe Containment of Arsenic-waste: A Sustainable Solution for Arsenic Crisis in Cambodia
EPA Grant Number: SU834717Title: Arsenic Removal and Ecologically Safe Containment of Arsenic-waste: A Sustainable Solution for Arsenic Crisis in Cambodia
Investigators: Sengupta, Arup K. , Ghosh, Ashok Kumar , Pallin, Chea , Uy, Davin , Kumar, Manish , German, Michael , Smith, Ryan , Sarkar, Sudipta , Padungthon, Surapol
Institution: Lehigh University , Institute of Technology of Cambodia
EPA Project Officer: Page, Angela
Phase: I
Project Period: August 15, 2010 through August 14, 2011
Project Amount: $10,000
RFA: P3 Awards: A National Student Design Competition for Sustainability Focusing on People, Prosperity and the Planet (2010) RFA Text | Recipients Lists
Research Category: Pollution Prevention/Sustainable Development , P3 Challenge Area - Chemical Safety , P3 Challenge Area - Safe and Sustainable Water Resources , P3 Awards , Sustainable and Healthy Communities
Objective:
The hot, tropical region of South East Asia, including Bangladesh, Vietnam, Laos, Cambodia, etc., annually receives 1000 mm of rain. If properly conserved and treated, the plentiful surface water should provide adequate, safe water to people. Neither proper sanitation practices nor infrastructure systems are established in this region, and their combined establishment is not feasible for quick, broad application because of the huge capital investments in construction, education, and business involved in surface water based treatment and distribution systems. On the other hand, microbiologically safe drinking water is available aplenty at shallow aquifers underground. This dilemma led to India’s 1970s push to reduce intestinal diseases by installing drinking water wells. Ingestion of arsenic-contaminated water causes health-related impairments that lead to societal troubles: social isolation, increased job losses, medical expenses, physical needs, stress on women and children, and premature death. Arsenic is the most toxic natural groundwater contaminant. Throughout all of South East Asia, there are many shallow and deep water wells that produce water with highly toxic concentrations of arsenic, causing the largest case of mass poisoning in history. In order to save future lives and to create a prosperous society, there is an urgent need to provide cost-effective, easy-to-operate arsenic removal technology commensurate with the present water collection habits and practices in Cambodia. A proven, highly scalable, long-term, sustainable solution for arsenic free ground water is regenerable, arsenic-selective adsorbents.
Under Phase I funding from EPA, a test hybrid anion exchange (HAIX) system was installed in Cambodia. HAIX arsenic treatment has been extensively proven in India and Bangladesh, but prior to expansion in each new environment, thorough testing and validation are necessary. Using a full-scale system, the viability of HAIX for groundwater arsenic removal in Cambodia was investigated by:
- Analyzing the column’s influent and effluent water quality to verify effective operation of HAIX in terms of Cambodia’s water standards
- Determining the reduction of waste produced per regeneration cycle in comparison to a non-regenerable system
- Quantifying the containment and leachability of arsenic from landfills and coarse sand filters to ensure protection of the environment in Cambodia and the USA
- Evaluating the effectiveness of outreach and education on community buy-in and integration of HAIX-produced water into consumers' lives.
It is important to note the emphasis given not just to short-term water quality standards, but to community buy-in and people’s involvement in their water supply.
Summary/Accomplishments (Outputs/Outcomes):
The technical results from the Cambodia installation have been positive. The HAIX wellhead unit is treating highly contaminated influent water (containing 1000 ppb As) and producing effluent water with <10 ppb As. The column is yet to require regeneration, but systems are in place for regular regeneration. The column is backwashed regularly in order to remove iron and arsenic precipitates before HAIX treatment and to keep the sand bed functional. The waste containing iron and arsenic from backwashing is being collected on top of coarse sand filters and is being stored in an oxidizing environment to prevent future leaching of arsenic that otherwise could poison people and the environment. Maintaining a highly aerated environment inside the coarse sand filter is crucial to preventing any leaching of arsenic into soil or water. The local water committee and technician have been actively engaging the consumers and developing positive relations.
Community members prefer the taste and availability of the filtered, arsenic-safe water to their previous distant, unsafe water sources. After the column became operational, the water committee partnered with local motorized rickshaws (tuk-tuks), and created a water vending business. This business doubled the number of consumers versus initial column use within the immediate community. The physical and psychological burden of transporting large volumes of water significant distances greatly limits the potential beneficiaries of one remote HAIX column. Distribution and sales of safe water through tuk-tuks has huge potential for increasing water access, providing jobs and microfinance support, and increasing prosperity for community members. From experience, local NGOs, such as Resource Development International- Cambodia (RDIC), agree with Lehigh University (LU) that the tuk-tuk-based water distribution is a very scalable means to meet the community’s water demand by using established community practices.
The results of the society-oriented tasks were more subjective, with several lessons learned during setup and operation. Communication with the community prior to installation of the HAIX-system did not effectively eliminate all concerns; past arsenic systems were not effective for long-term use. Thus, there was initial confusion about what was being installed, why it was installed at the specific location, how the system works, etc. Community buy-in, specifically through people’s money and time, is the reason for the success of community-based water treatment systems: all paying members have a strong interest in the return of a quality, valuable good for their payment. When the system needs repair or regeneration, the water is of low quality, or other problems arise, the well users will pressure the technician to do what is necessary for proper operation. Individuals who are not educated on the benefit and function of the system will not invest nor access the new water. Therefore, educational programs from our partners at RDIC were instrumental in teaching the people about the health benefits of arsenic-safe water and the effectiveness of the wellhead unit. These lessons, however, came during and after installation. Future community efforts in Cambodia, will first educate and communicate with a community about their opportunities for arsenic-safe water. After which, the community’s desire for a HAIX column, and related upkeep expenses, will ensure long-term investment and sustainability of the system.
Conclusions:
The following is being achieved through HAIX wellhead systems:
- More than 100 families are drinking arsenic-safe and microbiologically safe water.
- The regenerable nature of the resin is reducing the volume of disposable arsenic-laden waste 100-fold and decreasing costs by 67% versus single-use systems.
- Simple, cheap aerated coarse sand filters are being proven as effective means to dispose of arsenic-laden wastes and to prevent arsenic leaching in Cambodia and the USA.
- Water distributors are earning a living and doubling the number of beneficiaries.
- Connections between local communities, NGOs, Institute of Technology of Cambodia (ITC), and LU are growing stronger.
New knowledge developed during operations in Cambodia will enable further distribution of arsenic-safe water if a network of HAIX wellhead units is established. Before new community systems are installed, adequate communication and education must be developed so that the community is invested prior to column installation. This buy-in will ensure high system functionality and minimize people’s concerns during the system’s lifetime. However, resin costs must decrease to create a network of HAIX systems.
Journal Articles on this Report : 3 Displayed | Download in RIS Format
Other project views: | All 3 publications | 3 publications in selected types | All 3 journal articles |
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Sarkar S, Blaney LM, Gupta A, Ghosh D, SenGupta AK. Arsenic removal from groundwater and its safe containment in a rural environment: validation of a sustainable approach. Environmental Science & Technology 2008;42(12):4268-4273. |
SU834717 (Final) |
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Sarkar S, SenGupta AK, Prakash P. The Donnan membrane principle:opportunities for sustainable engineered processes and materials. Environmental Science & Technology 2010;44(4):1161-1166. |
SU834717 (Final) |
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Sarkar S, Greenleaf JE, Gupta A, Ghosh D, Blaney LM, Bandyopadhyay P, Biswas RK, Dutta AK, SenGupta AK. Evolution of community-based arsenic removal systems in remote villages in West Bengal, India: assessment of decade-long operation. Water Research 2010;44(19):5813-5822. |
SU834717 (Final) SU833759 (Final) |
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Supplemental Keywords:
adsorbent regeneration, arsenic, arsenic containment, arsenic removal, Cambodia, community-based, control technologies, groundwater, groundwater protection, HAIX production facility, hazardous waste, heavy metals, hybrid anion exchange, India, indigenous materials, international, iron adsorbent, leachate, Lewis acid-base interaction, local production, microfinance, pollution prevention, pollutants/toxics, production facility, redox environment, regeneration facility, sales, social entrepreneurship, sorbent, spent regenerant, sustainable development, sustainable industry, sustainable business, sustainability, technology for sustainable environment, toxics, waste minimization, waste reduction, water, water distribution, zirconiumThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.