Analysis Distribution of Iron (Fe) and Hexavalent Chromium (Cr6+) Contaminants in Shallow Groundwater Due To Leachate Around Landfill Terjun, Medan CityRonald Siregar, Munir Tanjung, Tresa Roselina and Yaumal ArbiE3S Web Conf., 519 (2024) 03022DOI: https://doi.org/10.1051/e3sconf/202451903022