GROUNDWATER QUALITY AND CONTAMINATION INDEX MAPPING IN CHANGCHUN CITY, CHINA

1INTRODUCTIONGroundwater in Changchun City assures about 45% of total water supply. Drinking water supply of Chang-chun City was mostly served by surface water from Shitoukoumen and Xinlicheng reservoirs located in the east and south of the city (ZHANG, 1993). However, with the development of urban construction the ground-water especially from deep boreholes is also used for drinking purpose in suburban areas. The urbanization process in Changchun City threatens the groundwater quali…

Groundwater quality and contamination index mapping in Changchun City, China

Groundwater in Changchun City, Jilin Province of China tends to be influenced by human activities. Chemical types of groundwater were detected in both shallow and deep groundwater were: HCO ₃ ⁻ -Ca²⁺ and HCO ₃ ⁻ - Ca²⁺ · Mg²⁺ or HCO ₃ ⁻ -Mg²⁺ · Ca²⁺; SO ₄ ²⁻ -Ca²⁺ and SO ₄ ²⁻ - Ca²⁺ · Mg²⁺; Cl⁻ - Ca²⁺; and CO ₃ ²⁻ - Na⁺. The deteriorations of groundwater quality due to the increase of TDS, NO ₃ ⁻ +NO ₂ ⁻ (as Nitrogen) and TH contents have been observed from 1991 to 1998. Scatter analyses showed strong positive correlations between Ca²⁺, Cl⁻ and NO ₃ ⁻ ions and weak negative correlations between the depth of water table and Ca²⁺, SO ₄ ²⁻ Cl⁻ and NO ₃ ⁻ ions. A mapping of contaminant index based on Chinese standard of groundwater showed that a large proportion of the groundwater in 1998 was deteriorated by human process. Despite their low values of sodium adsorption ratio (SAR), the most of the sampled wells were not suitable for drinking and agriculture purposes due to higher contents of NO ₃ ⁻ , NO ₂ ⁻ and Mn²⁺ ions. Foundation item: Under the auspices of China Scholarship Council Biography: Hamadoun BOKAR (1966–), male, a native of Mali, Ph. D. candidate, specialized in water pollution assessment. E-mail: hamadounbokar@yahoo.com