In order to determine what variables are involved in the phenomenon of preferential deposition of corrosion products on fuel element surfaces, Van de Graaff studies were initiated. Studies of the effect of high pH and oxygen on the release and deposition of corrosion products from carbon steel are presented. Results on the effect of added salts on deposition and the results of a preliminary attempt to determine whether the fractional deposition of available corrosion product iron is dependent on the concentration of corrosion products in the water are reported. (W.L.H.)