Risk Based Land Management and Sustainable Rehabilitation of Radioactive Contaminated Territories
Total Page:16
File Type:pdf, Size:1020Kb
Decision-Making Support within Risk Based Land Management and Sustainable Rehabilitation of Radioactive Contaminated Territories B.Yatsalo *), I.Okhrimenko *), I.Pichugina *) O.Mirzeabassov *), V.Didenko *), D.Okhrimenko*), V.Golikov #), G.Bruk #) and V.Shutov #) 1) [email protected] ABSTRACT Description of the applied Decision-Support System (DSS) PRANA for Risk Based Land Management (RBLM) and rehabilitation of radioactive contaminated territories is presented. PRANA is a unique DSS developed with the use of GIS technologies which comprises all the main territories of Russia subjected to radioactive contamination as a result of the Chernobyl accident (Bryansk region) and includes all the models and tools necessary for decision-making support on local and regional levels within RBLM and rehabilitation of contaminated territories. Examples of PRANA implementation for scientific and practical assessments are considered. Keywords: radioactive contamination, radiation protection, risk based land management, rehabilitation, doses, countermeasures, GIS, decision support systems, PRANA DSS. INTRODUCTION Despite improvement of the radiological situation for the 16 years after the Chernobyl accident, the latest monitoring data and assessments demonstrate that the situation on the contaminated territories of Bryansk region (Russia) is far from satisfactory. Fraction of milk for 5 districts of Bryansk region with contamination above formal action level exceeded in 2001 20% (for Novozybkov district - 60%); about 50% of the rural population live in settlements with a mean dose above 1 mSv/y (formal dose level for exemption from intervention). As a rule, contamination of private agricultural produce, which constitutes the majority of foodstuffs of the local population, substantially exceeds contamination of farm produce. This is caused by use of more contaminated lands for farming private production and fewer protective measures. Model estimations demonstrate that optimization of agroecological and administrative countermeasures along with enhancement of the skills of living on contaminated territory can considerably decrease contamination of agricultural production and doses to the local population. In this condition implementation of up-to-date information technologies for decision-making support on risk based land management (RBLM) and optimization of countermeasures (CMs) within the programs on rehabilitation and sustainable development of contaminated territories is more than actual [1-4]. PRANA DSS for RBLM and COUNTERMEASURE OPTIMIZATION Analysis of the current situation in contaminated farms and settlements of Bryansk region is based on the monitoring data and model estimates. Model assessments of agricultural produce contamination, doses to the local population, radiological risk and results of CMs implementation have been carried out with the use of PRANA GIS-DSS [3,4,9]. Applied Geographic Information System (GIS) PRANA is a DSS for rehabilitation of radioactive contaminated territories. The following versions of DSSs have being developed (family of PRANA systems, each of them is intended for analysis of the specific range of problems): - PRANA-P - GIS-DSS for practical use within decision-making support on rehabilitation of radioactive contaminated territories of Bryansk region on regional and local levels; PRANA-P consists of the following sub-systems, which may be used independently: PRANA-DB-Analysis, PRANA-Agro and PRANA-Dose; - PRANA-R - GIS-DSS for research and for scientific and practical estimations (this version of PRANA comprises all the possibilities of the systems indicated above along with some additional 1) *) Obninsk State Technical University of Nuclear Power Engineering, Obninsk, Russia #) Institute of Radiation Hygiene, St.-Petersburg, Russia 2 applications, including block of CMs optimization and uncertainty analysis and has completely new architecture); - PRANA-E/T GIS-DSS for education and training of students and experts. PRANA-P has been introduced for practical use in Bryansk (as well as for scientific and practical assessments at several institutes and centres) as a GIS-DSS for monitoring networking support, assessing radiation indices and countermeasure analysis. The main blocks of PRANA DSSs are: - libraries of digital maps, including different layers of vector maps of landuse for all contaminated districts of Bryansk region: Novozybkov, Klintsy, Gordeevsky, Krasnogorsky, Zlynkovsky and Klimovsky (more than 30000 polygons of vector electronic maps), Fig.1; - databases (radioecological, ecological, economic, demographic and other monitoring data and model parameters, including attributive information for each polygon of vector electronic maps); - model blocks for assessing: contamination of agricultural production, external and internal doses to the local population, radiological risks and corresponding results of CMs implementation; - evaluation of CMs effectiveness and decision-making support on protection of the population and rehabilitation of radioactive contaminated territories both on local and regional levels (from separate settlement/field up to group of settlements/farms and district/region as a whole), [4, 5]. FiFigg..1.1. LaLandndususee mmaapp Landuse types: ffoorr 66 ddiissttririccttss settlement ofof BBrryayansnskk rreegigionon arable natural lands forest fallow land bushes marsh reservoir Structure of other land agricultural lands % for 6 districts 80 70 70 60 50 40 30 18 12 20 10 0 Arable lands Pastures Hayfields Klintsovsky district % 69,5 70 60 50 40 30 20,3 20 10,2 10 0 Arable lands Pastures Hayfields The following (generic) ‘risk indices’ are considered within RBLM and decision-making support with the use of PRANA DSS: - surface density contamination of territory with radionuclides (137Cs, 90Sr); - contamination of agricultural production (plant growing and animal husbandry, including farm and private production); - external and internal doses to the local population (mean doses and doses for different age and occupational groups of each settlement for region under consideration); - radiological risks caused by irradiation of the population; - and expenses associated with CMs implementation and rehabilitation procedures along with corresponding criteria of effectiveness on the basis of CBA analysis. 3 Special attention is paid to estimation of agricultural produce contamination for each agricultural field, farm (farm production) and settlement (private production) taking into account farm specialization (real data on crop rotation and cattle stock) and particularity of private farming. Ranking fields, farms, settlements and districts has been carried out with the use of several criteria: surface density contamination (including separately for arable lands, pastures and hayfields), contamination of a given product, dose to the local population and percent of exceeding corresponding DILs/ILs by indicated values. Realization of radiological protection principles includes solving the following tasks within the work package on optimization of CMs structure. 1) (Research task) Analysis of effectiveness (for a given set of criteria) for each CM for various radiological, ecological, socio-economic and other conditions. 2) (Direct task) Determination of the specific territories/objects (fields, settlements, farms) for a given region where CMs can be or should be implemented according to a strategy of rehabilitation; determination of corresponding means (cost, materials, etc.); assessment of effectiveness for each CM and system of CMs for site-specific conditions; analysis of alternatives. 3) (Inverse task) Taking into account the set of available CMs and objects of possible implementation of CMs (agricultural fields, settlements), experts have to chose such their subset, that realization of the chosen CMs on chosen objects/polygons provides an optimal value for a given criteria and satisfies conditions of financial and other (ecological, economic, etc.) restrictions/constraints. Decision-making support on the basis of different versions of GIS-DSS PRANA on rehabilitation of radioactive contaminated territories (including managing farm production and decreasing doses to the local population using different agricultural and administrative countermeasures) can be carried out both on local and regional levels. Such an approach is realized through presentation of source data and various model estimates on the level of: - separate agricultural field (including each arable field, pasture/hayfield); - a set of agricultural lands (e.g., for fields under a given crop or for specific soil types, for pastures/hayfields, or for any group of agricultural lands indicated by user); - a settlement or a group of settlements; - farm or a group of farms; - specific administrative district, a group of districts or the whole contaminated territory (of Bryansk region). At that, for each level of decision-making support source/modelled information can be presented for users/experts/decision-maker as - electronic map(s); - table(s); - graphic(s)/diagram(s). On the basis of PRANA DSS all the main source and derived maps (along with corresponding statistical characteristics) which are used within agriculture managing, assessing the structure of doses to the local population, protective measures planning and, as a whole, within rehabilitation of radioactive contaminated territories, can be presented. The most claimed within the indicated problematic are the following source maps with corresponding statistical