Assessment of Groundwater Contamination from Nitrate in Mashad City

Groundwater is one of the major sources in providing water supply for central and country side of many cities. Groundwater provide as much as 88% of total water consumption in Mashad. Nitrate contamination in groundwater resources originates mainly from excessive fertilizers and uncontrolled land discharges of treated wastewater. Nitrate can cause potential health hazards for infants and pregnant women, thus limiting the direct use of groundwater resources for human consumption in several parts of the world. The purpose of this study was to evaluate nitrate occurrence in groundwater sources of Mashad. The results of this study on different groundwater samples in different parts of the city showed that nitrate has increased in recent years and its value in some parts is more than 50mg/l. The nitrate pollution of groundwater was due to sanitary and industrial wastewater. This study showed that nitrate levels in groundwater over vast agricultural areas can be correlated with use of nitrogenous fertilizers.