ABSTRACT
Groundwater contamination by flow from surface water is known to take place in some portions of the country (Fuhriman and Barton, 1971; Bethune et al., 1996; Bonomi et al., 1994; Farrah and Lukasik, 1997). Undoubtedly, it is also oc curring in many other places, yet undetected. Water applied during irrigation [URL Ref. No. 241] and that which tem porarily covers surface areas during floods are examples of how the mechanisms for contaminants enter the soil, pass downward into aquifers [URL Ref. No. 322], and become established (Kelly, 1939). Surface waters from open bodies (e.g., rivers, lakes) can enter into aquifers where groundwater levels are lower than surface water levels. Pumping from shallow wells near a stream and infiltration of water into soil from flash runoff occurrences in dry stream chan nels are other methods of how this type of groundwater con tamination can occur.
