We use locally sourced alum and chlorine tabs in a two step treatment process (similar to what you would see in a centralized treatment system). For Saha it is important that all of the materials for the treatment centers can be sourced locally so the communities are not dependent on Saha to keep their centers operational. For the water quality testing and ongoing monitoring we have a team on the ground that visits each community 1-2x / month (tapers with time). On a community visit the Saha team member speak with the local entrepreneurs about water sales and any issues they are having with the center and a water sample is collected. We then then randomly select 6 households to visit to discuss their use of the clean water and to take water samples from their safe storage container in their home. These samples are all tested in the Saha field lab in Tamale using Colilert water tests. The cost of water quality testing and monitoring is included in Saha's quoted implementation costs.