Title: Radiological assessment of radioactive waste disposal from non-nuclear premises in Anglian region. Vol. 2 : results
Author: G.D. Burholt
Author: A. Martin
Document Type: Monograph
Abstract:
This Report has been prepared by Alan Martin Associates for the Anglian Region of the Environment Agency (EA) under Contract Ref. PO()35/DOSE/CT. The objective of the work covered by the contract is to undertake an assessment of the radiation doses to critical groups from authorised disposals and discharges of radioactive waste from premises other than nuclear sites within the Anglian Region. The present report comprises Volume 2 and sets out the detailed results of the assessment of the radiation doses that would result from disposals of radioactivity at the limits of the authorisations for all non-nuclear premises in the Anglian region. The assessments are based on the methodology and data presented in Volume 1, using the details on authorisations compiled in Volume 3. Generally, the assessments have considered bounding situations and, in some cases, the pathways identified as making the major contributions might not be currently applicable. Nevertheless, in most cases, there remains the potential for the pathway to become applicable. Similarly, the parameters used in assessing the impacts through the various pathways are generally such as to provide upper limit estimates. In some authorisations, in addition to specified radionuclides there is an allowance for other radionuclides, excluding alpha emitters. This provides flexibility to users, particularly to hospitals, where new techniques may need to be used at short notice to suit particular situations. Where such a category is specified in an authorisation, the assessment has been based on a radionuclide giving a relatively high impact per unit release. For release to atmosphere, the assessment is based on 1-125 and for liquid releases Co-58. For releases to atmosphere, the results show that the impact of discharges at the limits of authorisation would, in most cases, result in doses to most exposed groups of less than 1 jj.Sv per year. For a small number of premises, the impacts are estimated to be a few jiSv per year and only in one case does the estimated impact exceed 10 (iSv per year. The only area in which there is a sufficient concentration of authorised premises such that the combined impacts might need to be considered is Cambridge. However, it is shown that the combined radiological impact would be less than 1 |iSv per year. The assessments of discharges of radioactive liquid effluents via public sewage treatment works indicate that discharges at the limits of authorisations would result in doses exceeding 10 jj.Sv per year at seven of the public sewage treatment works. In all of these cases, the impact is mainly from 1-131 through the irrigation pathway. The highest impact is 203 fiSv per year from discharges to the River Cam from Milton sewage treatment works. Analysis of the impacts of the combined discharges from all the public sewage treatment works on a river system shows that they do not result in significantly increased impact down the catchment system. In general, the impact declines down the catchment as a result of increasing dilution. The highest overall estimated impact from liquid effluent discharges is about 250 fiSv per year due to the sewage sludge pathway from the private sewage treatment plant at Conoco Ltd, Grimsby. The main contributor to the dose is H-3 for which the authorised limit is 1.8 TBq per year. Direct discharges to the North Sea from the Conoco Ltd. Plant at Theddlethorpe would, at the limits of authorisation, result in a dose of about 50 fiSv per year to a critical group of fish consumers. In this latter case, the impact is due to naturally occurring radioactivity from the processing of natural gas. There is only one authorisation for disposal to landfill in the region and the assessed impact of this is shown to be very low.
Publisher: Environment Agency
Publication Date: 1999
Publication Place: Surrey
Subject Keywords: Radioactive pollutants; Waste disposal; Radiolysis; Assessment
Geographic Keywords: EA Anglian
Extent: 84
Permalink: http://www.environmentdata.org/archive/ealit:1249
Total file downloads: 69
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