BNFL Environmental Services has developed a formulation to encapsulate borate-rich liquid radioactive waste from the primary cooling circuit of the Kozloduy plant in Bulgaria.

John Miller, BNFL Environmental Services project manager, said: “This liquid waste, generated by decontaminating power station coolant loops, contains material that would normally inhibit cement solidifying. So, we first had to develop a simulant of the waste before moving onto producing a formulation that can withstand rigorous physical testing regimes ­ alternate freezing and thawing to +/-40°C every day for 28 days.” BNFL Environmental Services has now handed over the formulation to the Kozloduy plant, where the grout is now being used in active commissioning trials.