“…There are many factors influencing the per sistence and activity of pesticides in the treated soils, including nature of the compounds, characteristics of the soil, land usage and management practices, topography, and climatic conditions White, 1964 and.1970;Bamett et al, 1967;Harris and Lichtenstein, 1961;Merkle and Bovey, 1974;Ruckelshaus, 1972). Dominant factors are solubility of the pesticides (Ashton, 1961), organic content of the soil (Adams and Li, 1971;Harris, 1967 andHarris and Sans, 1967;Miles et al, 1978;Sheets et al, 1962;Yaron et al, 1967), cultivation of the soil (Baker et al, 1976;Lichtenstein et al, 1971), rainfall intensity, duration, and the timing of first heavy runoff relative to application (Baker and Johnson, 1977;Hass et al, 1971;White et al, 1967). In addition, degradation of pesticides to form other compounds, such as DDT to DDE and DDD, aldrin to dieldrin, and heptachlor to its ide, is commonly observed in the soil environment (Eichelberger and Lichtenberg, 1971;Gannon and Bigger, 1958;Lichtenstein and Schulz, 1960;Matsumura, 1973;Matsumura et al, 1968;Plimmer et al, 1968;Wedemeyer, 1966).…”