tailieunhanh - NATURAL ARSENIC IN GROUNDWATER: OCCURRENCE, REMEDIATION AND MANAGEMENT - CHAPTER 9

Chất tan từ các nguồn ô nhiễm khác nhau ảnh hưởng đến hệ thống tầng nước ngầm Salamanca. Các chất thải rắn của ngành công nghiệp hóa học khác nhau đã được xử lý tại các bãi nằm xung quanh khu vực đô thị. Asen, chì và benzene là một số các chất ô nhiễm được báo cáo trong nước ngầm tại địa phương. Hầu hết các giếng nước đô thị Như nội dung trong tiêu chuẩn quốc gia đối với nước uống. Nước ngầm là nguồn nước duy nhất cho các cư dân Salamanca | Natural Arsenic in Groundwater Occurrence Remediation and Management -Bundschuh Bhattacharya and Chandrasekharam eds 2005 Taylor Francis Group London ISBN 04 1536 700 X Arsenic contamination of the Salamanca aquifer system in Mexico a risk analysis R. Rodriguez . Armienta Instituto de Geofisica Universidad Nacional Autónoma de México UNAM . Del Coyoacan Mexico City México . Mejia Gomez Consejo Tecnico delAgua COTAS Irapuato-Valle de Santiago Gto. Mexico ABSTRACT Solutes coming from different pollution sources are affecting the Salamanca aquifer system. The solid wastes of different chemical industries were disposed in dumps located around the urban area. Arsenic lead and benzene are some of the reported pollutants in the local groundwater. Most of the urban wells reported As contents over the national standard for drinking water. Groundwater is the only water source for the Salamanca inhabitants. An aquifer vulnerability assessment was done using the DRASTIC method. A vulnerability zoning a potential pollution sources inventory and a population survey permitted a risk analysis. The most critical areas are related to a subsidence fault that is acting as a preferential channel for pollutants particularly for hydrocarbon residuals. The fault permits the hydraulic communication between an unexploited shallow aquifer and the exploited unit. Evidences of health affectation were not found. Three urban wells located near of the fault were closed. 1 INTRODUCTION Arsenic As contamination in groundwater is becoming a serious problem for the institutions in charge of water supply management and administration. In Mexico the number of areas with groundwater As content greater than the Mexican standard for drinking water is increasing. The associated risks of consumption of As contaminated water are well known by the authorities but not by the population. In some cases groundwater is the main source of potable water. Adverse health affects due to chronic exposure to As