The measurement of beta dose and gamma air kerma rates in the Ribble Estuary

Abstract

As a by-product of the fabrication of uranium fuels, BNFL, Springfields are authorised to discharge beta emitting rardionuclides, principally into the Ribble Estuary. The accumulation of in the estuarine sediments leads to enhanced beta dose rates not seen elsewhere in the UK. The methods used to determine the beta dose rate and calculate organ and effective doses are presented. The variation in beta dose and gamma air kerma rates in a small area were investigated and recommendations are made as to the number of replicates needed to reduce the error to of the mean. An example of the dose to a walker on the intertidal areas of the Ribble Estuary is calculated by the detailed methods. The effective dose was , of which 86% was derived from gamma irradiation. Doses to hands contaminated by estuarine sediments are also low .