Being that it is an essential condition for life, water in inadequate conditions could be a social determinant which can, in turn cause specific illnesses, either by direct or indirect contact, with the ingestion of non-potable water, deriving from inadequate reservoirs for human consumption; contact with contaminated water and exposure to vectors related to the water. In vulnerable areas, the source of fresh water utilized by human beings suffer a continuous and increasing degradation process due to the disposal of sewage in natura or infected with animal feces and waste disposal in open air contaminating the water table; in addition, serving as breeding spots for mosquitoes in their immature stages, transmitters of human disease agents. Such a fact is the result of disorganized population growth and the lack of covering sewage disposal and adequate treatment of waste in the most vulnerable areas. The open dump located in Brasilia, has been used as an area for the indiscriminate disposal of waste in the soil since the sixties. It is Latin America’s biggest open dump and receives 9,000 tonnes of waste per day. Currently there are, working there and living nearby, almost 2.000 waste pickers of recyclable materials and their families who are in a situation of extreme social vulnerability and health. Based on data provided by Regulating Agency for Water, Energy, and Basic Sanitation of the Federal District – (ADASA) resulting from monitoring of groundwater campaigns in the landfill area, this study identifies and evaluates the importance of the actors involved in the surveillance, monitoring and preservation of water quality, discusses the contamination degree of groundwater, and analyzes the risk of vulnerability of the population directly affected. After monitoring the porous and fractured domain wells over three years, it can be concluded that there are evidences for groundwater contamination in the vicinity of Structural's controlled landfill. The fact is rather worrying, because the region where the landfill is located is a watershed, where people who use water from wells for drinking water live, a fact that can lead to several health problems. This statement is corroborated by the results obtained from data analysis, which indicated parameters such as electrical conductivity, chlorides, alkalinity, iron and lead in high values and some of them at odds with the Brazilian legislation for drinking water and groundwater quality for human consumption. These study's results are expected to highlight the importance of water quality used for consumption by waste pickers who work at the landfill and surrounding areas pointing out to knowledge of the risks on the current sanitation, health, and environmental problems in this site. In addition, it is intended to propose integrated and intersectoral actions for improving health of waste pickers and the public health as well as preserving and protecting the environment.