Arsenic remediation in rural wells
Arsenic exposure is recognized by the World Health Organization and agencies such as the U.S. EPA as a significant threat to human health. Long-term exposure to arsenic via drinking-water causes cancer of the skin, lungs, urinary bladder, and kidney, as well as other skin changes such as pigmentation changes and thickening (hyperkeratosis). The problem of arsenic in drinking water is not unique to Peru, but it is relatively understudied. The state of groundwater is of particular concern in this area because many rural communities are drawing increasingly on wells for drinking water as growing informal urban settlements contaminate streams and rivers. Our tests of wells indicate that as many as 30 percent of wells in the area may have unsafe levels of arsenic, and some range as high as 500 parts per billion. The World Health Organization's maximum contaminant level for human consumption is 10 parts per billion.
This project aims to enable rural families located in these arsenic “hot spots” in Puno to acquire a simple arsenic filtration device for water used for cooking or drinking. In June 2011, a group of volunteers from the Chijnaya Foundation, the Puno-based nonprofit Suma Marka, the University of California-Berkeley Chapter of Engineers without Borders, and Regional Health Directorate (better known by its Spanish acronym, DIRESA) constructed the first pilot filters for this effort utilizing porous iron scraps from machine shops in Puno, wood charcoal, washed sand, polyester fiber, and bits of brick. The filters were installed in June and July 2011 in health posts in two localities with elevated arsenic, with the goal of field-testing the filters and taking monthly data on arsenic removal rates and filtration flows
The project will begin in Carancas, Peru (pop. 2,500) and Paucarcolla (pop. 1,200). If successful, the pilot phase of the project may also extend to Bolivia through the Terra Foundation, where well tests in similar geology have indicated elevated arsenic there as well. We estimate that there may be 100,000 or more people in the basin with elevated arsenic in water; this pilot project would serve approximately 400-500 households; full buy-in from the DIRESA with a microenterprise in filter construction could reasonably cover all households in the basin at risk.
The training will be followed up with monitoring through a twelve month period by local health authorities and the staff of Suma Marka, who will consult recipients’ about whether they are using the filters, test filtered water to ensure proper functioning of the filters, and ensure that technicians are building filters according to specifications.