Justification of modernization of groundwater treatment station Zhanna Govorova, Olga Zubareva, Vasiliy Semenovykh, Ekaterina Muraveva and Olga Yankovskaya E3S Web Conf., 263 (2021) 04049 Published online: 28 May 2021 DOI: 10.1051/e3sconf/202126304049