Testosterone, androstenedione and estrogen are present in animal manures and are constantly excreted into the environment.  Previous reports have indicated the inter-convertible estrogens, estradiol and estrone, are immobile in soil while, of the two androgens, - testosterone is mobile and reaches the groundwater and androstenedione is partially mobile.  To study the transport of these compounds in the vadose over long time exposure (30 yr), we studied a dairy barn with 50 dairy cattle.  This was calculated as a load of 36 kg estrogens and 7 kg androgens. All of the effluent was released into 15 x 10 m lagoon, which drained toward a dry creek, creating a constant overflow of about 300 meters long and 1-4 meters wide.  The lithology under the waste lagoon consists of 8 m of clay layer on top of sand and calcareous formation and the water table was at a depth of 47 m. Soil samples (5 g) were extracted with organic solvents and analyzed using radioimmunoassay or Elisa.   Groundwater samples (500 ml; after pumping four well volumes) were extracted on C-18 solid extract columns and similarly analyzed.  It was found that testosterone and estrogen were present in the clay zone at concentrations of greater than 500 ng/kg) and <100 ng/kg in the sandy zone while androstenedione <100 ng/kg was present only in the clay zone. Testosterone and estrogen, but not androstenedione, were present in the groundwater (3 ng/l).  The level of the steroids in control soils and groundwater taken 1 km upstream from the site were below the limit of detection.  We conclude that unlike previous reported, estrogen can be transported in the vadose zone and can reach the groundwater after long time exposure to dairy barn effluents. The concentrations of estrogen observed were above the amount known to affect soil bacteria and aquatic fauna.