成都市某区1起幼儿园生活饮用水污染事件调查

Contamination Incident of Drinking Water in a Kindergarten in Pidu District

目的调查成都市郫都区某幼儿园生活饮用水污染原因,发现可能存在的污染源、污染途径,采取有效控制措施,避免对该园师生健康造成潜在不良影响。方法采用现场流行学调查的方法进行调查,采集的水样按《生活饮用水标准检验方法》进行检验,并依据《生活饮用水卫生标准》对水质检测结果进行评价。结果水源井修建于2009年,井深12 m左右,机器取水,水源井水未做任何消毒处理。水源井约4 m处有一卫生厕所,水源井距幼儿园化粪池约12 m,距污水沟约14 m,由于所有管道及化粪池均埋于地下,最近是否发生溢水,无法获知。被污染生活饮用水检出总大肠菌群、氨氮11.6 mg/L(限值:0.5 mg/L),超过国家生活饮用水卫生标准限值。结论本次事件的污染来源可能是由于化粪池水及生活污水污染水源井,从而导致总大肠菌群和氨氮超标。

Objective To investigate the causes of drinking water pollution and found possible sources of pollution, in order to take effective control measures and to avoid the potential adverse health effects of teachers and students of the kindergarten. Methods An on - site investigation on the contaminated drinking water was carried out, and water samples were collected for laboratory detection and evaluation, according to the Drinking Water Standard Test Methods. Results The well was built in 2009, depth of it was about 12 m, used water machine and without any disinfection. The well was about 4 meters from the toilet, about 12 m from the septic tank and about 14 m from the sewer. Because of the pipes and septic tank were all covered underground, unable to know whether overflow was happened or not. The contents of coliforms and Ammonia nitrogen were 11.6 mg/L （ limited level： 0.5 mg/L） in the water samples, were higher than the national limits prescribed in standards for drinking water quality. Conclusion The sources of pollution of this incident may be due to septic tank water and domestic sewage pollution of water wells, resulting coliforms and ammonia nitrogen seriously exceeded.