World population is reaching record highs, 6 billion and counting, and the most sought after resource of the 21st century will not be oil but clean water. In 1990 the WHO revised its estimates of access to safe drinking water, they concluded that 43% of the world's population is lacking adequate sanitation and 22% do not have access to clean drinking water. Heavy reliance is beginning to come from underground aquifers as surface water begins to become scarce.
Nordstrom (1998) discussed the risks associated with groundwater and heavy metal pollution. His review in the policy forum outlined that groundwater utilization comes with high risks, such as the 36 million people in the Bengal Delta now suffering from arsenic. Arsenic is not found in high abundance in the Earth's crust and is strongly associated with pyrite, a prolific mineral. Areas that have high levels of arsenic are Kamchatka, New Zealand, Japan, Alaska, California and Wyoming, areas where there are young basalt rocks. Environments such as closed basins in arid and semi arid climates and areas that have aquifers with strong reduction properties are all prone to arsenic collections. Nordstrom does, however, highlight that although these environments are condusive to arsenic it doesn’t help us to predict a high or low concentration, primarily due to the heterogeneous spread in the aquifers. Arsenic is highly soluble and as such its concentrations and distributions in aquifers can change within a few years. This results in constant monitoring to pre-empt arsenic entry into ground water enterprises in high risk areas.
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