PRELIMINARY INORGANIC SURFACE WATER QUALITY ANALYSIS OF THE GATUNGA STREAM NEAR AN UNLINED LANDFILL IN GATUNGA, KIGALI PROVINCE, RWANDA

Landfills are necessary parts of urban and rural sanitation systems. Water that infiltrates landfills may, however, leach out toxic elements that could contaminate nearby ground and surface water. Unlined landfills allow for water, which has passed through the landfill, to more easily penetrate the ground water and get into surface water. In late July 2017, during Rwanda's dry season, we took water samples from six sites along the Gatunga stream, its tributaries, and the Nyabugogo River, all of which are located downstream of an unlined landfill near Kigali, Rwanda.

The samples were analyzed for elemental concentrations using ICP-MS and preliminary results indicate that concentrations of lead, arsenic, cadmium, barium, and other elements sometimes associated with landfills were all below the US EPA primary drinking water standards and aquatic life surface water guidelines. The water was moderately hard and exhibited pH levels that ranged from pH 5-6. The hypothesis has shown that elemental concentrations will increase because the samples were taken during the dry season when little to no rainfall infiltrated the landfill. Additional research is needed to test for organic compounds and to assess and compare results from the rainy season with these results from the dry season.