Indoor Air Quality Assessment in Terms of CO2 level & Odor Dispersion on Residential Buildings Neighboring to Reppie (Koshe) Landfill Site: Addis Ababa City, Ethiopia

Abstract

Landfill Odor and CO2 pollution are components of the pollutants affecting the human environment indoors and outdoors around landfills. The study was conducted in koshe landfill with the objectives to analyze the effect of the Reppie (Koshe) landfill on the indoor air quality of the residents around it, focusing on the dispersion of CO2 and Odor to identify the areas which can be impacted by CO2 and odor released from the landfill and examining the concentration of CO2 inside residential buildings around Koshe in the extent of 1.5km radius. To delineate the odor and CO2 zones of influence, the air dispersion properties of the odor and CO2 gases were analyzed using the dispersion modeling software, Areal Locations of Hazardous Atmospheres (ALOHA), and mapped with ArcGIS, Part of the study consists of a perception survey to determine the influence of odors on the level of indoor comfort. Carbon dioxide (CO2) concentration was measured using aeroqual series 500 portable air quality measuring instrument inside the sampled residential houses within the radius of 1.5km. The findings of the study show that odor and CO2 impact zone tool showed that atmospheric stability, the dominant northwestern and southeastern wind directions could increase the odor impact radius around the landfill evaluated between 322 and 540 percent and the result from CO2 dispersion suggest that in June CO2 had a smaller concentration of emission than in April. However, the maximum distance for the dispersion of CO2 in June was found to be longer than that in April. Descriptive statics using figures and tables were employed to present research findings concerning the survey result. the result implies the level of CO2 in the radius of 500m was greater than the values taken within the radius of 500m-1.5km even though all values don’t exceed the standard values, the valuesindicatesthat koshe landfill hassome contribution to the increase of CO2 level considering the landfill as the only source. 34% of the residents agree that koshe have caused indoor malodor contribution to the indoor environment, from the results of the study it is highly recommended that mitigation measures such as Planting green belt as Buffer around the landfill and Passive solution for residential Buildings