A Hybrid Multi-Sensor Monitoring Framework for Spatial Screening of Particulate and Gaseous Pollutants around a Tropical Urban Landfill

Abstract

Open landfills generate complex mixtures of particulate and gaseous pollutants that can affect nearby communities. However, distance alone does not adequately explain their short-term spatial distribution. This study characterized multiple air pollutants surrounding the Tamangapa Landfill in Indonesia, compared concentrations between near and outer zones, and examined their relationships with distance and meteorological conditions. Field observations were conducted at nine locations situated 200–640 m from a central reference point. PM₁.₀, PM₂.₅, PM₁₀, formaldehyde, total volatile organic compounds (TVOC), CO, CO₂, CH₄, H₂S, O₂, and the lower explosive limit (LEL) were measured using complementary portable sensors. Analytical methods included descriptive statistics, Mann–Whitney tests, Cliff's delta, Spearman correlations, and Benjamini–Hochberg corrections. Particulate concentrations exhibited substantial spatial heterogeneity, with maximum PM₁.₀, PM₂.₅, and PM₁₀ concentrations of 146, 242, and 272 µg/m³, respectively. Mean concentrations in the near zone were approximately 3.6–3.7 times higher than those in the outer zone. TVOC showed a strong negative correlation with distance (rₛ = −0.812; p = 0.0079), although this association did not remain statistically significant after correction for multiple testing (q = 0.063). Pollutant distributions appeared to reflect interactions among distance, plume orientation, meteorological conditions, measurement time, and local activities. This study introduces a hybrid multi-sensor screening framework that integrates particulate, gaseous, spatial, and meteorological measurements for tropical landfill environments, particularly in resource-limited settings where conventional monitoring networks remain limited.