ON 12/22/2001, A DISCHARGE OF AN UNKNOWN QUANTITY OF OIL REACHED THE WEBER RIVER. THIS DISCHARGE FROM THE RIVERBANK NEAR A WATERFALL (800 YARDS SOUTH OF THE RIVERDALE OVERPASS) CONSTITUTES A SUBSTANTIAL THREAT TO PUBLIC HEALTH OR WELFARE. UNION PACIFIC HAS BEEN ORDERED TO MAINTAIN BOOM AROUND THE SOURCE OF THE SEEP AND MAINTAIN 7 BOOM STATIONS DOWNSTREAM OF SEEP. THEY MUST REPLACE SATURATED BOOM AS NECESSARY AND INVESTIGATE THE SOURCE OF THE SEEP.