辐射环境保护类微机程序包概述

“辐射环境保护类微机程序包”集成了３５个辐射环境影响评价程序,实现了所有这些程序向微机的移植,完成了使用频率较高的程序之间的连接,增添了原有程序的报表输出和图形化处理功能,并且,结合我国辐射环境影响评价的规范,评价了这些程序在辐射环境影响评价中的适用性。辐射环境类微机程序包由正常气载、正常液载、放射性货包运输、核事故应急、废物处置、事故放射性后果、剂量转换因子七大功能块组成,基本覆盖了辐射环境影响的所有方面     

Environmental Protection in the Tomsk Region of the Russian Federation: A Case Study

/ Implementation of environmental management in Russia is undergoing rapid changes. Federal responsibility rests with the Russian Federation State Committee for Environmental Protection (RFSCEP) and is delegated at regional level to local State Committees for Environmental Protection (SCEPs). This paper focuses on the functioning of the SCEP for Tomsk oblast' (region) in Siberia, which is strongly committed to forging constructive links with regional government, academia, industry, and environmental NGOs. Considerable difficulties exist for SCEPs in Russia, however, and prominent among these are (1) a rigidly vertical civil service structure, with separate organs having responsibility for different natural resources, persisting from Soviet times, which hinders effective intergrated and holistic environmental management; and (2) a lack of open access to environmental information from military and quasi-military sites.     

样品中总α/β放射性的测量

以某一比对样品中总α/β放射性的测量过程为例,叙述了样品预处理、上机测量及参数确定的方法,并结合实践,对工作中需要注意的问题进行了探讨。     

塔克什肯口岸土壤放射核素含量调查研究

利用高分辨半导体能谱分析方法分析了新疆塔克什肯口岸土壤天然放射性核素铀238、镭226、钍232、钾40和人工放射性核素铯137的含量,共选取8个采样点16个土壤样品及4个煤炭及废旧金属样点。结果表明:进口货物道路各采样点其铀238、钾40及铯137均比非进口货物道路各点高,镭226、钍232含量则相反,而煤炭和废金属的各样品的铀238、镭226、钍232、钾40都高于进出口道路和非进口道路,Cs137则相反,表明进口煤炭和非金属对天然放射性核素产生了较大影响,而对人工放射性核素影响较小。和新疆及全国背景值比,进口道路和非进口道路土壤中各放射性核素含量均未超过天然本底值范围,进口煤炭和废金属虽然各放射性核素含量则略高于背景值,表明试验点没有受到放射性污染,对当地居民和进出境人员不会产生辐射伤害。     

Radiological risk assessment and biosphere modelling for radioactive waste disposal in Switzerland

Long-term safety assessments for geological disposal of radioactive waste in Switzerland involve the demonstration that the annual radiation dose to humans due to the potential release of radionuclides from the waste repository into the biosphere will not exceed the regulatory limit of 0.1 mSv. Here, we describe the simple but robust approach used by Nagra (Swiss National Cooperative for the Disposal of Radioactive Waste) to quantify the dose to humans as a result to time-dependent release of radionuclides from the geosphere into the biosphere. The model calculates the concentrations of radionuclides in different terrestrial and aquatic compartments of the surface environment. The fluxes of water and solids within the environment are the drivers for the exchange of radionuclides between these compartments. The calculated radionuclide concentrations in the biosphere are then used to estimate the radiation doses to humans due to various exposure paths (e.g. ingestion of radionuclides via drinking water and food, inhalation of radionuclides, external irradiation from radionuclides in soils). In this paper we also discuss recent new achievements and planned future work.     

Modelling remediation options for urban contamination situations

The impact on a population from an event resulting in dispersal and deposition of radionuclides in an urban area could be significant, in terms of both the number of people affected and the economic costs of recovery. The use of computer models for assessment of urban contamination situations and remedial options enables the evaluation of a variety of situations or alternative recovery strategies in contexts of preparedness or decision-making. At present a number of models and modelling approaches are available for different purposes. This paper summarizes the available modelling approaches, approaches for modelling countermeasure effectiveness, and current sources of information on parameters related to countermeasure effectiveness. Countermeasure information must be applied with careful thought as to its applicability for the specific situation being modelled. Much of the current information base comes from the Chernobyl experience and would not be applicable for all types of situations.     

Mapping of the geogenic radon potential in France to improve radon risk management: methodology and first application to region Bourgogne

In order to improve regulatory tools for radon risk management in France, a harmonised methodology to derive a single map of the geogenic radon potential has been developed. This approach consists of determining the capacity of the geological units to produce radon and to facilitate its transfer to the atmosphere, based on the interpretation of existing geological data. This approach is firstly based on a classification of the geological units according to their uranium (U) content, to create a radon source potential map. This initial map is then improved by taking into account the main additional parameters, such as fault lines, which control the preferential pathways of radon through the ground and which can increase the radon levels in soils. The implementation of this methodology to the whole French territory is currently in progress. We present here the results obtained in one region (Bourgogne, Massif Central) which displays significant variations of the geogenic radon potential. The map obtained leads to a more precise zoning than the scale of the existing map of radon priority areas currently based solely on administrative boundaries.     

Cs contamination of the Techa river flood plain near the village of Muslumovo

The results of a radiometric survey of the Techa river flood plain near the village of Muslumovo in the Chelyabinsk region of Russia are presented. The observed territory extended 16.6 km along the riverbed, with a total area of 2.5 km². The collimated scintillation detector technique was applied to in situ field measurements of ¹³⁷Cs deposition on the soil. Maps of ¹³⁷Cs deposition and soil penetration depth were developed on the basis of approximately 5000 measurements. The total ¹³⁷Cs deposition within the surveyed territory has been estimated at 6.6 TBq. The means of the total ¹³⁷Cs soil depositions at half-kilometer sites on the flood plain and its distribution along the river have also been calculated. A maximum ¹³⁷Cs contamination above 7.5 MBq/m² is associated with a bank height up to 1 m above the usual water level. The data identify zones of intensive radionuclide sedimentation and transit zones.     

Modelling radionuclide distribution and transport in the environment

Mathematical models of radionuclide distribution and transport in the environment have been developed to assess the impact on people of routine and accidental releases of radioactivity from a variety of nuclear activities, including: weapons development, production, and testing; power production; and waste disposal. The models are used to estimate human exposures and doses in situations where measurements have not been made or would be impossible or impractical to make. Model results are used to assess whether nuclear facilities are operated in compliance with regulatory requirements, to determine the need for remediation of contaminated sites, to estimate the effects on human health of past releases, and to predict the potential effects of accidental releases or new facilities. This paper describes the various applications and types of models currently used to represent the distribution and transport of radionuclides in the terrestrial and aquatic environments, as well as integrated global models for selected radionuclides and special issues in the fields of solid radioactive waste disposal and dose reconstruction. Particular emphasis is placed on the issue of improving confidence in the model results, including the importance of uncertainty analysis and of model verification and validation.