1983 was the year of the "Beach Discharge Incident" in which high radioactive discharges resulted in the closure of a beach. BNFL received a fine of £10,000 for this discharge. 1983 was also the year in which Yorkshire Television produced a documentary "Windscale: The Nuclear Laundry", which claimed that the low levels of radioactivity that are associated with waste streams from nuclear plants such as Sellafield did pose a non-negligible risk.
In its early days, Sellafield discharged low-level radioactive waste into the sea, using a flocculation process to remove radioactivity from liquid effluent before discharged. Metals dissolved in acidic effluents produced a metal hydroxide flocculent precipitate following the addition of ammonium hydroxide. The suspension was then transferred to settling tanks where the precipitate would settle out, and the remaining clarified liquor, or supernate, would be discharged to the sea. In 1994 the Enhanced Actinide Removal Plant (EARP) was opened. In EARP the effectiveness of the process is enhanced by the addition of reagents to remove the remaining soluble radioactive species. EARP has recently (2004) been enhanced to further reduce the quantities of Tc-99 released to the environment.
Category: Power - Nuclear