§ Ms AthertonTo ask the Secretary of State for Defence if he will publish past and current methods of treatment for(a) pralidoxime mesylato, (b) arsenic chloride and (c) a mixture of ethylphosphonyl dichloride and ethylphosphonyl difluoride before disposal. [5790]
709W
§ Dr. MoonieThe materials are no longer prepared in large scale in the Ministry of Defence and bulk treatment methods are not currently required. All laboratory waste is now incinerated or sent to a hazardous waste contractor as appropriate.
The following information outlines the procedures used for disposal of these chemicals during the decommissioning of Nancekuke in 1980. Pralidoxime mesylate was dissolved in water and treated with sodium hypochlorite (bleach) before being discharged into the sea though the effluent system.
Arsenic Chloride was hydrolysed in water and the product was treated with sodium hypochlorite. This was then diluted into the effluent system until the sodium arsenate discharged was less than 234 parts per million.
The mixture of ethylphosphonyl dichloride and ethylphosphonyl difluoride was hydrolysed then neutralised, probably with caustic soda, before being diluted and discharged into the sea through the effluent system.