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- ISSN: 2333-2581
- Modern Environmental Science and Engineering
Nitrate Concentrations in Rural Potable Water Wells From Eight Regions of Chile
Abstract: Nitrogen exists naturally forming part of the biotic and abiotic, but input from fertilizers overuse as nitrate is increasing it polluting water sources, impairing human and ecosystem’s health. This is important in Chile when it’s facing the warmest decade of the last century with a decrease in precipitation in the north and central macroregions. A groundwater quality monitoring network using rural water wells is managed since 2014 by the DGA in 8 Chilean regions: Coquimbo, Valparaiso, Metropolitana, O’Higgins, Maule, Ñuble, Biobio and Los Rios. The data gathered between 2014-2019 considers field parameters and nitrate, which are analysed in this paper to identify the physicochemical characteristics of the groundwater of the regions and its aquifers, and also to diagnose the nitrate concentration “state” using a warning limit of 30 mg NO3/L and the maximum concentration recommended by the national guideline for potable use (NCh 409 of. 2005) of 50 mg NO3/L. The results indicate that nitrate concentrations are mostly below 50 mg NO3/L, with Coquimbo, Valparaiso and Metropolitana as the regions with the highest concentrations, and with quality improving towards south. Data length among regions and within aquifer is low calling for an urgent increase in monitoring frequency, mostly coverage. Nevertheless, it’s possible to recommend preservation efforts of groundwater in aquifers from the 8 regions, and also highlight that aquifers Culebron-Lagunillas, “Sin Informacion”, Aconcagua, Casablanca, Maipo, Cachapoal, Tinguiririca, Mataquito and Maule-Medio are not providing water with quality enough for potable purposes without nitrate treatment.
Key words: nitrate pollution, groundwater quality in Chile, Rural Water Wells (APR), National Water Agency (DGA) monitoring network
