Theme 8. Emergency preparedness and response

doi:10.4103/0972-0464.368747

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Year : 2023 | Volume : 46 | Issue : 5 | Page : 418-439

Theme 8. Emergency preparedness and response

Date of Web Publication

07-Feb-2023

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DOI: 10.4103/0972-0464.368747

How to cite this article:
. Theme 8. Emergency preparedness and response. Radiat Prot Environ 2023;46, Suppl S1:418-39

How to cite this URL:
. Theme 8. Emergency preparedness and response. Radiat Prot Environ [serial online] 2023 [cited 2023 Mar 28];46, Suppl S1:418-39. Available from: https://www.rpe.org.in/text.asp?2023/46/5/418/368747

Abstract - 81185: Assessment of emergency planning zones and optimum protective actions required during early phase of nuclear emergency for off-site EPR Plans of Indian PHWRs

Amit Kumar, K. Girish Kumar, Nrependra Kumar, Manoj Kansal, Rajee Guptan

Directorate of Reactor Safety and Analysis, NPCIL, Mumbai, Maharashtra, India

E-mail: [email protected]

The early phase of nuclear emergency, during which little or no information is available, is very important in terms of response actions. During this phase, it is necessary to act promptly to reduce the consequences of the radioactive release to the environment. The only information during this phase of emergency that can be used confidently to take protective actions decision is the plant parameters. Plant specific events/observables or conditions [Initiating Conditions (ICs)/Emergency Action Levels (EALs)] play a very important role and can form the basis of emergency classification and triggering/deciding protective actions. Identifying the Emergency Planning Zones [Precautionary Action Zone (PAZ) & Urgent Protective Action Planning Zone (UPZ)] at planning stage helps for pre-developing infrastructure and facilities for quick response in these areas during emergency. Emergency Planning zones around Indian NPPs have been determined realistically following IAEA post Fukushima guidelines.^[1] Consequence analysis is done with spectrum of reasonable releases of radioactive material to atmosphere for more than or near to 700 weather sequences, which represents past five year meteorological condition of respective sites. Based on 95^th percentile of weather conditions, PAZ and UPZ is estimated for all the operating PHWR sites as given in [Table 1]. The effect of accident in public domain can be mitigated by developing emergency preparedness and response plan prior to the operation of nuclear facility that can be practiced using exercises and can be implemented if an accident occurs. Therefore, it is necessary to develop optimum protection strategy for each postulated initiating conditions which may lead to off-site emergency at planning stage based on historic meteorological conditions. Optimum protection strategy has been developed to address the emergency exposure situation by focusing on the precautionary and urgent protective actions to mitigate off-site consequences. Consideration has been given to both effective dose and organ dose (thyroid). In the current approach, reference level (100 mSv) is introduced; where any planned protection strategy (combination of action) aims to reduce exposures below this level, with optimisation achieving still lower (< 20 mSv effective dose) residual dose. A protection Strategy is developed for all the initiating conditions such as Loss of Coolant accident (LOCA) or Station Black out (SBO), etc., which may lead to severe fuel damage with core melt and to contain the molten core in Calandria vault, SAMG actions are taken appropriately. Containment filtered venting system (CFVS) is operated at design pressure of containment to confine the radioactivity and depressurizing the containment. The optimum protection strategy developed for LOCA and SBO initiated severe accidents in IPHWRs is summarized in [Table 2]. It can be seen that during severe accidents, public can be protected with timely implementation of protective actions such as ITB, Sheltering and Food control & restrictions (FC&R). There would be no requirement of evacuation in the public domain, if CFVS is operated as per design. Further, practically there would not be any requirement of early evacuation and permanent relocation at Indian PHWR sites, as containment integrity is ensured by augmenting the safety features. The containment related events such as containment isolation failure; can be recovered in few minutes by manual action and late failure of containment due to hydrogen are prevented by installation of Passive Catalytic Recombiner Devices (PCRDs). Prompt response can be implemented by timely identification of emergency situation. Protective actions in public domain must be taken shortly after the particular off-site IC is identified (based on EALs). This IC based initial protective action recommendation to off-site officials is termed as EAL/IC based decision making and through this approach public can be protected effectively during early phase of emergency.

Table 1: Size of emergency planning zones

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Table 2: Optimum protection strategy for IPHWRs

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Keywords: Emergency preparedness, initiating conditions, PAZ, protection strategy, UPZ

Reference

International Atomic Energy Agency. Actions to Protect the Public in an Emergency due to Severe Conditions at a Light Water Reactor. Vienna: International Atomic Energy Agency; 2013.

Abstract - 81197: Preparedness for nuclear/radiological emergency by DAE radiation emergency response centre, in India

Sanjay S. Patil, T. R. Meena, S. Murali

Radiation Safety Systems Division, Bhabha Atomic Research Centre, Mumbai, Maharashtra, India

E-mail: [email protected]

Radioactive materials are widely used in medicine, industry, agriculture, research applications and power generation. There could be potential threat from any lapse in safety/security of material, could lead to nuclear / radiological emergency. Nuclear or radiological incidents arise due to involvement of state agency or due to malicious acts by non-state actor. To detect and prevent any developing event arising due to human error, abnormality in safety system, it is feasible by radiation early warning systems. To interdict suspected events or detect malicious acts, it is feasible by network of installed radiation monitors, mobile radiation detection systems installed in police patrol vehicles of major cities and wide area radiation monitoring systems on mobile (aerial/drone) platforms. At all NPP sites, the Environmental Survey Laboratory (ESL) is located in public domain, equipped with radiation monitoring instruments, protective equipment, personnel decontamination centre and communication facility. ESL is mandated to gather dynamic radiological on-field details, estimate radiological impact during emergency. Thus, the technical evaluation of any radiological event can be effective in a shortest duration of time. Presently, preparedness measures are available with plan, procedures and hierarchy of response personnel in DAE Radiation Emergency Response Centre (DAE-RERC). DAE-RERCs are established and operated with trained human resource, expertise available with state of the art monitoring systems, tools for assessment and planning response. Emergency Communication Room (ECR) is operated 24*7 by Crisis Management Group (CMG-DAE), Mumbai and CMG-DAE serves as a single window coordination agency for effecting the technical assessment and rendering technical advice for field response. To strengthen the emergency preparedness system periodic mock-emergency exercises are conducted on plant, site and off site emergency situations. During 2010, DAE-RERC carried out response actions to mitigate the consequences, for a radiological emergency event at Mayapuri, Delhi. In addition, DAE-RERCs provide necessary technical guidance for every suspected case of nuclear or radioactive materials in the public domain, based on the radiological evaluation/ assessment. Law enforcing agencies, civic administration personnel have been trained over a decade on preliminary details on radiation safety, detection, equipped with gadgets for radiological emergency response. Augmentation of the DAE-RERC capabilities and human capacity building among various response forces and civic administration personnel are carried out with futuristic view on response requirement. Network of DAE-RERCs and ESLs are spread over the country for handling potential emergency against Nuclear/Radiological emergencies and can ensure quick and effective response to large scale events anywhere in the country. DAE-RERCs are also equipped with latest monitoring gadgets with online data transfer and communication facility and further augmentation of DAE-RERCs would be helpful to prevent, interdict and prepare towards an early and quick radiation emergency response.

Keywords: DAE-radiation emergency response centre, emergency preparedness and response, environmental survey laboratory, nuclear and radiological emergency

Reference

Pradeepkumar KS. Nuclear and Radiological Threats and Emergency Preparedness at National Level. IARP; 2008.

Abstract - 81290: Implementation of international standards for emergency preparedness and response in Indian NPPs

K. Girish Kumar, Amit Kumar¹, Srijith Valsan, K. Venkata Ramana, K.K De

Directorate of Health Safety and Environment, NPCIL, ¹Direcrtorate of Reactor Safety and Analysis, NPCIL, Mumbai, Maharashtra, India

E-mail: [email protected], [email protected]

Introduction: Standard procedures are followed in the design, construction and operation of nuclear power plants to incorporate a high degree of safety. Atomic Energy Regulatory Body (AERB) also carries out detailed and independent safety assessment of the facilities and has an elaborate programme of licensing and inspection at different stages of construction and operation. Therefore, probability of an accident resulting in the release of large quantities of radioactivity is extremely small. The probability, however, can never be reduced to absolute zero and therefore this residual risk is sought to be mitigated by appropriate siting criteria and implementing suitable arrangements for emergency preparedness and response (EPR). In the unlikely event of an accident, adequate preparedness for protection of the plant personnel, members of the public and the environment from radiation exposures needs to be ensured. Need for change in EPR plan: Based on the experience of Fukushima Daiichi accident, there have been significant changes in handling and response to a nuclear emergency situation. The importance of decision making during initial period of an emergency was felt. During the initial period of nuclear emergency, there is very little information available with respect to the radiological impact. During this phase, it is necessary to act promptly to reduce the consequences of the radioactive release to the environment. The emergency preparedness and response plan comprise a set of consistent protective actions, adapted to local conditions at nuclear sites, taking into account the societal, environmental, and economic factors that will affect the impact of the accident and its response.

Changes in the Response Framework: Revision of the existing arrangements for emergency preparedness and response is carried out at all the Nuclear power stations of NPCIL in line with the AERB guidance and recommendations of IAEA provided through the Safety Standards.^[1] Changes have been implemented in the classification of emergency through Initiating Conditions (IC) and Emergency Action Levels (EAL). Decision making based on this classification will strengthen the preparedness for emergency response for triggering/deciding appropriate protective actions. The clear understanding of the phenomena involved, and its prognosis will help in taking an effective protective actions. Precautionary Action Zone and Urgent Protective Action Planning Zones are identified for each nuclear power plant sites of NPCIL for pre-developing infrastructure and facilities for quick response in these areas during emergency. For the management of a nuclear emergency, the timeline of the accident is divided into Early, Intermediate and Late Phase considering aspects such as the status of the release, the type and urgency of measures, the type and availability of resources, and the relevance of exposure pathways. Changes has been implemented in the response arrangement with roles and responsibilities clearly defined. Off-Site Emergency resulting in radiation fallout in the public domain is handled by district authorities headed by Responsible Officer (RO) /Incident Commander (IC) with technical guidance from the Site Emergency Director (SED) of the facility during the early Phase of the accident. During the intermediate and late phase, the technical guidance to the District authorities will be given by the Radiation Emergency Response Director (RERD) - DAE. Decision Support System (DSS) software is also introduced to support decision-making process in the early phase of the emergency. Based on the existing plant conditions and actual weather conditions, protective actions are recommended for implementing in the affected villages. A Protection strategy is also identified for each postulated ICs which may lead to off-site emergency to reduce the exposure below the reference level. Integrated Command Control and Response (ICCR) exercise with focus on the decision making and response in the early & intermediate phases, is being conducted regularly at all NPCIL units.

Conclusion: Changes implemented in line with the International standards will help effectively to respond to a nuclear emergency by carrying out Protective actions that will do more good than harm.

Keywords: Emergency preparedness, ICCR exercise, initiating conditions

Reference

Preparedness and Response for a Nuclear or Radiological Emergency, IAEA Safety Standards, GSR Part-7. Vienna: 2015.

Abstract - 81388: Protection strategy for Kalpakkam site due to scenario emanating from PFBR

N. Suriyamurthy, Vidhya Sivasailanathan, Allu Ananth

Health Physics Unit, BHAVINI, Kalpakkam, Tamil Nadu, India

E-mail: [email protected]

Introduction: PFBR is a 500 MW(e) nuclear power plant that has potential for large inventory of radioactive materials in its operation. Magnitude and likelihood of radiation exposure in emergency exposure situation is unpredictable since both sources of exposure and pathways of exposure are not under control. However, the exposures can be controlled only by taking appropriate protective actions. GSR, Part-7,^[1] requires that the protection strategy shall be developed, optimized and justified at preparedness stage. This manuscript discusses about the protective action recommendations (PAR) for various initiating conditions (IC) based on dose criteria as part of protection strategy developed for the nuclear emergency if emanates from PFBR.

Materials and Methods: In case of PFBR, the postulated severe accident is Core Disruptive Accident (CDA) which is a highly improbable event (10^-6/ry) but has potential to cause wider radiological consequences. The development of protection strategy for NPP is multistep process which is based on basis of emergency planning, hazard assessment, reference level etc. Aim of protection strategy is to fulfil the emergency response by minimising or avoiding the severe deterministic effects using RBE weighted absorbed dose and reducing the probability of the detriment due to stochastic effects in terms of effective dose. ICRP suggested reference level of 20- 100 mSv is given due weightage in terms of residual dose. In early phase of emergency, the effective dose of 100 mSv whereas in late phase 20 mSv are justifiable.

Results and Discussion: The initiating condition (Category-Malfunction) involves Accidental withdrawal of control rods + failures of automatic and manual shut down systems + Containment isolation failure, will lead to release of radioactivity beyond the site boundary which calls for activation of offsite response plan. Emphasis is given for the condition in which core damage coupled with containment breach warrants declaration of offsite emergency. The radiological impact assessment is performed for 1.5 km, 2 km, 4 km, 7 km, 10 km,16 km and 30 km distances for the estimated release indicated that the dose is monotonically decreased with distance. All undelayable protective actions are recommended for implementation in precautionary urgent protective action zone (PAZ) which houses nuclear facilities.^[2] Protection Strategy is considered for various initiating events originating due to system malfunction and fission products barrier breach. [Table 1] indicates applicable PAR.

Table 1: Protective action recommendations

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References

GSR Part-7, IAEA; 2015.
Off-Site EPR Manual, for Kalpakkam Site (Rev-7).

Abstract - 81468: Evolution of a performance based emergency exercise methodology for effectively testing preparedness for emergency response

S. P. Lakshmanan, Ritu Raj, S. K. Dubey, Deepak Ojha

Directorate of Radiation Protection and Environment, Atomic Energy Regulatory Board, Anushaktinagar, Mumbai, Maharashtra, India

E-mail: [email protected]

A well planned emergency response system is the last defense for protecting people and environment from radiation releases caused by certain accident scenarios at nuclear or radiation facilities. The effectiveness of this emergency response actions depends on the level of preparedness for emergency. A continual training and a comprehensive exercise programme is therefore essential to accomplish the overall objective of protecting the public and environment during an emergency. It was identified that the current procedures for conduct of emergency exercise needs to be revisited and new methodology has to be evolved in order that the exercises facilitate the assessment of decision making and filed response capabilities, especially during the early phase of an off-site emergency. In order to evolve a comprehensive exercise plan, a mapping of Off-Site Emergency Exercise (OSEE) elements against the existing practice was carried out to identify the gap areas, for their inclusion in the new approach and evolution of the procedures. With the intent to involve the various elements and to address the gap areas, a scheme having modular and integrated approach with different types of exercise was laid out to cover the various objectives of the emergency exercise. The evolved comprehensive exercise plan has the primary intent of addressing the elements of decision making, technical response, field response, effective coordination and other programme elements. These were covered through different exercise type viz.

Table Top Exercise (TT): Emphasizing on technical decision making process;
Integrated Command Control and Response (ICCR) Exercise: For testing command control functions, timeline for decision making and response, communication and phase wise response;
Field Exercise and Demonstration: Resource mobilization and demonstration of public protective actions domain.

The salient features of the new exercise methodology are:

Challenging the decision makers to respond in an unknown realistic scenario (plant and weather condition)
Exercise scenario not known to the players and exercise progresses through use of injects for specifying the conditions.
Exercise scenario development and finalization. Scenarioinclude core melt conditions and release from containment.
Emergency classification and Protective actions based on plant conditions during early phase of emergency and subsequently based on field data.
Check response time line for declaration, activation and field actions for early warning and response.
Effectiveness of the liaison between on-site and off-site facilities for sharing information and making decisions.
Coordination between plant and District authorities for public information during an emergency.
For the Licensee, all emergency exercise objectives including onsite actions (i.e. quarterly PEE, yearly SEE, biennial TT- OSEE and triennial ICCR OSEE) are addressed over a specified period.

The methodologies were evolved through conducting trial exercises at various NPP Sites to gain insights and feedback for finalization. As an important feature the exercises were conducted in a realistic environment where, the information on the event and possible consequence are not known to the response organizations participating in the exercise. In addition, criteria for assessment of emergency exercise were developed to evaluate the performance against identified response time targets and other exercise objectives. The new performance based exercise methodology has allowed for an effective assessment of preparedness of the response organizations and for identifying gap areas for necessary corrective actions and continual improvement.

Keywords: Assessment, emergency exercise, table-top

Abstract - 81473: Overview of communication strategy during nuclear/radiological emergency: An Indian context

Vikas, R. K. B. Yadav, S. Murali, T. R. Meena, C. D. Karekar, P. Devender, R. V. Chavan

Radiation Safety System Division Health, Safety and Environment Group, Bhabha Atomic Research Centre, Mumbai, Maharashtra, India

E-mail: [email protected]

Introduction: Effective Risk Communication plays a pivotal role in implementation of decisions to reduce adverse impact through urgent protective actions and other associated response actions taken during all phases of Nuclear/Radiological Emergency. It is also equally integral to other type of emergency response. BARC Trombay, a multi-disciplinary research organization houses nuclear facilities like Dhruva, APSARA(U) etc. Communication strategy has been devised, enacted and adopted for effective implementation of decision during emergency which cater to need of various language speaking employees of BARC. During emergency, Department of Atomic Energy and its constituent unit use the same model to communicate among its workforce and with members of public at large. Any announcement/declaration related to nuclear/radiological emergency is announced in Hindi, English and state language to understand the message conveyed whether it is a start of nuclear/radiological emergency, during the emergency or its termination. This paper highlights the importance of multiple language communication strategy in reducing the impact of nuclear/radiological emergency through establishing trust with the affected people.

Methodology: Crisis Management Committee at BARC is the highest decision-making body on emergency response for the site facilities of BARC, Trombay. From past several years Public Address & Siren System (PA&SS) is in use at facilities of BARC for announcing any emergency/exercise related decision. Additionally, communication through megaphone during exercise/emergency is also carried out. The message of announcement is carried out in Hindi, Marathi, and English successively for effective communication at BARC.

Results and Discussion: Radiation & conventional emergency exercises are carried out, as per regulatory requirement at BARC Trombay is shown in the given [Table 1].

Evaluation of data suggests that the adopted communication strategy is a satisfactory mechanism. Plausible reason could be that its workforce is well versed with do's and don'ts during emergency exercise which is also a resultant of devised communication strategy of announcement in normal time (during exercise) as well as in emergency situations. Proactive approach of involved agencies is a key aspect of emergency response. This reduces the possibility of any fortuitous incident and overcome language barrier which may reduce the effectiveness of implemented countermeasures. In order to reach to general public and to propagate message at greater pace, the role of digital media can't be ruled out. Affirmative approach of media will reduce rumor mongering during nuclear/radiological emergency at national/state level. Access to reliable, timely and accurate information made available to public is crucial during phases of nuclear/radiological emergency and is helpful to gain public confidence. Effective risk communication allows people to better understand and adopt protective actions during emergency. An all-inclusive and Expansive Emergency Risk Communication Plan is the exigent need of the hour.

Conclusion: Experience has shown that the communication strategy adopted during emergency exercise is unique but persuasive. People in stressful environment may go haywire due to misinterpretation of message conveyed in a particular language thereby reducing the efficacy of procedural implementation of decision taken to avert radiation exposure. Dissemination of exact information is critical during initial hours and is an integral part of emergency response. To enhance the efficacy of procedural implementation of decisions taken, database of recorded & pre-recorded text and voice based automated message system in plain, simple and multiple languages may be developed. In this fast changing time where the information travels at a passing of swipe/tap/click a two-way dynamic communication tool may be developed to communicate with the affected people during all stages of nuclear/radiological emergency management.

Table 1

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Keywords: Communication strategy, crisis, nuclear/radiological emergency, risk communication

References

Wray RJ, et al. Am J Public Health 2008;98:2214-22.
IAEA. General Safety Requirements Part 7. Vienna: IAEA; 2015.
Ramlan SN, et al. Manag Sci Lett 2018;8:659-66.

Abstract - 81480: Current regulatory requirements and guidance on emergency preparedness for management nuclear emergency in India

Shivaji Krishna Pawar, B. Venkataraman¹, J. Bhavani²

Atomic Energy Regulatory Board, Mumbai, Maharashtra, ¹Indira Gandhi Centre for Atomic Research, Kalpakkam, ²Vellore Institute of Technology, Chennai, Tamil Nadu, India

E-mail: [email protected]

Introduction: Nuclear power plants (NPPs) and nuclear facilities (NFs) in India are sited, designed, constructed, commissioned and operated with highest priority to nuclear safety. Emergency preparedness (EP) is 5^th level in the defence in depth concept. Regulatory oversight with respect to emergency preparedness in NPPs is done by Atomic Energy Regulatory Board (AERB). Regulatory body establish the requirements and guidance on EP, review and approve onsite emergency preparedness and response (EPR) plans, ensure implementation of onsite EPR plan and participate as observers in periodic exercises to verify regulatory compliance. The facility operator, in coordination with State and District authorities, develops the offsite EPR plans in accordance with regulatory requirements and national guidelines. This paper describes the current regulatory requirements and guidance and its silent features for emergency preparedness. Current Regulatory Requirements and Guidance: Current requirements and guidance for management of nuclear emergency include (a) Safety Code AERB/NRF/ SC/NRE on Management of Nuclear and Radiological Emergencies (b) AERB Safety Guidelines AERB/NRF/SG/ EP-5 on Criteria for Planning, Preparedness and Response for Nuclear or Radiological Emergency (c) Safety Guide AERB/SG/NRE-1 on Management of Nuclear and Radiological Emergency in NFs (d) AERB Safety Guidelines AERB/SG/EP-2 on Preparation of off-Site Emergency Preparedness Plans for Nuclear Installations (e) TECDOC on precautionary and urgent protective actions in response to nuclear emergency (f) Guidelines on development of initiating conditions and emergency action levels for classification of emergency (g) Revised offsite emergency exercise framework (h) Templates for EPR plans for offsite, site and plant emergency.

Salient Features of the Recent Regulatory Requirement and Guidance: Generic Criteria (in term of projected dose) and Operational criteria (Emergency action levels, operational intervention levels & observables) are now used in place of Intervention Levels (IL) and Derived Intervention Levels (DIL) for emergency declaration and implementing protective actions. The operational criteria is derived from generic criteria (b) For emergency preparedness and response, emergency zones are classified as (i) The precautionary action zone (PAZ) (ii) The urgent protective action planning zone (UPZ) (iii) extended planning distance (EPD) and (iv) Ingestion and commodities planning distance. The sizes of these zones are decided based on the radiological impact assessment of the NPPs (c) Emergency Preparedness Category is decided based on radiological impact assessment of NPPs/NFs, these are categorized into five classes (d) A reference levels are expressed in terms of residual dose. During the emergency phase, a reference level between 20 and 100 mSv per year are used for justification and optimization of the protective strategy (e) Protection strategies are developed at each NPP site considering radiological and non-radiological impact onsite and offsite (f) Guidance values in term of dose (30 mSv to 500 mSv) are provided for emergency workers to control their exposure during the various response actions (g) Decision Support System (DSS) for nuclear emergencies is intended to provide comprehensive and timely information to emergency managers on projected doses.

Conclusion: The current regulatory requirements and guidance developed and implemented by AERB for NPPs are consistent with IAEA safety standards and are in line with international practice.

Keywords: AERB, DSS, EAL, emergency preparedness, management, reference levels, zones and distances

References

Pawar SK, Srinivas CV, Venkatraman B, Bhavani J. Application of decision support system during the emergency exercises for nuclear emergency management. Int J Recent Technol Eng (IJRTE) 2019;8.
AERB Safety Guidelines AERB/NRF/SG/EP-5 “Criteria for Planning, Preparedness and Response for Nuclear or Radiological Emergency“.

Abstract - 82112: Development of an AHP-TOPSIS framework for assessing protection strategies

Anirudh Chandra, S. Murali

Radiation Safety Systems Division, Bhabha Atomic Research Centre, Mumbai, Maharashtra, India

E-mail: [email protected]

The philosophy of 'doing more good than harm' in the response to a nuclear emergency is imbibed in the concept of protection strategies, put forward by the IAEA and ICRP, on the basis of lessons learnt from the response to the nuclear emergencies at Three Mile Island, Chernobyl and Fukushima. The crux of this concept is that the choice of protection strategies should focus on mitigating the radiological consequences and avoid adverse non-radiological impacts^[1] through a comprehensive assessment at the preparedness stage with all the stakeholders involved. In this study, an integrated evaluation framework [Figure 1] was developed that comprised of two multi-criteria decision making (MCDM) methods^[2] – Analytical Hierarchy Process (AHP) and Technique for Order Preference by Similarity to Ideal Solution (TOPSIS)–to select a justified and optimised protection strategy. A hypothetical accident sequence at a light water reactor was postulated along with a set of protection strategies across the urgent and early phases of the emergency. The assessment criteria were prepared on the basis of analysis of several IAEA reports on past nuclear and radiological emergencies. The radiological criteria included – Averted Dose, Residual Dose, Surface Contamination Levels and Personal Contamination Levels. The non-radiological criteria included – Economic (Loss of Income, Loss of Revenue, Financial Burden, Exchequer Burden), Social (Injuries, Diseases, Psychological, Stigma, Fatalities) and Environmental (Loss of Land/Water, Loss of Flora/Fauna, Harmful Emissions). The AHP was used to obtain the criteria weights, a subset of which is shown in [Figure 2]. The TOPSIS was used to evaluate the strategies on the basis of stakeholder opinion matrix and the above weights. The outcome of the TOPSIS is shown in [Figure 3]. It was observed that the criteria weights varied across the phases of the emergency as the response priorities shifted from radiological to non-radiological. The TOPSIS ranking showed that the strategy that can avert the most dose (evacuation) is not always justified when assessed across all the criteria. The results of the framework were encouraging and, in the future, this would be used with other MCDM techniques as an ensemble to make it more robust to stakeholder opinion fluctuations.

Figure 1: Proposed framework for evaluating protection strategies

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Figure 2: AHP assessed criteria weights

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Figure 3: Strategies ranked by AHP-TOPSIS framework

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Keywords: Decision making, nuclear emergency, protection strategy

References

International Atomic Energy Agency. GSR Part 7. Preparedness and Response for a Nuclear or Radiological Emergency. Vienna: IAEA Safety Standards; 2015.
Abbas Mardani AJ. Multiple criteria decision-making techniques and their applications – A review of the literature from 2000 to 2014. Econ Res 2015;28:516-71.

Abstract - 82262: Methodology for estimation Emergency Planning Zone using deterministic methods for the PHWRs

P. Bhargava^1,2, Praveen Kumar¹, Brij Kumar¹, Lopa Basak¹, K. D. Singh¹, M. S. Kulkarni^1,2

¹Health Physics Division, Bhabha Atomic Research Centre, ²Homi Bhabha National Institute, Anushaktinagar, Mumbai, Maharashtra, India

E-mail: [email protected]

This study provides a basis for estimation of the size of the emergency planning zone and distances for the urgent protective actions and other response actions that will be taken upon declaration of general emergency for preventing the occurrence of severe deterministic health effects as well as to keep the doses below the generic criteria at which protective actions and other response actions are justified to reduce the risk of stochastic effects. Precautionary Action zone (PAZ) is on the basis of the absorbed dose of 1 Gy in one day to either fetus or bone marrow is considered in the present study. Similarly for Urgent Protective Action Zone (UPZ) is inhalation dose of 100mSv in seven day is considered.^[1] The PAZ is defined as the area within which arrangements are required to be made with the goal of taking urgent protective actions, before a severe release of radioactive material occurs or shortly after the release of radioactive material begins, on the basis of conditions at the nuclear power plant in order to substantially reduce the risk of severe deterministic effects. The UPZ is defined by the international requirements as the area within which arrangements are required to be made for urgent protective actions to be taken promptly in order to substantially reduce the risk of stochastic effects off the site.

Materials and Methods: Size of emergency zone has been estimated in a deterministic way using computer code COSYMA^[2] for the 220 MWe PHWR by providing proper consideration to the spectrum of reasonable releases of radioactive material and the behavior of radioactive material released to the atmosphere. The assumptions made for the release characteristics are summarized in [Table 1]. Only severe damage to the fuel in the reactor core can result in off-site consequences. Studies indicate that the majority of the releases to the atmosphere following severe fuel damage are projected to contain about 0.5–2% of the volatile fission products (e.g. I and Cs) in the fuel and the maximum expected to be released is about 10% (IAEA, 2013). Therefore, a release of about 10% of the volatile fission products into the atmosphere was assumed in the calculations. These studies also indicated that a severe release would probably occur over many hours, for this reason a 10 hour release was assumed. Proper attention is given to the meteorological condition for the estimation of the PAZ and UPZ. Stability category D with 2 m/sec wind speed was considered with 90⁰ changes in wind direction over the 10 hour period of release. Results were presented in the graphical form for PAZ and UPZ.

Conclusion and Discussion:PAZ distances are 3.5 km on the basis of bone marrow and fetus dose. Similarly it is 7 Km for UPZ on the basis of the effective dose. Proper emergency preparedness plan exist around all the NPP sites to substantially reduce fetus dose to public using Iodine Thyroid Blocking (ITB). Bone marrow and effective dose are used for deciding the PAZ and UPZ distances.

Figure 1: Projected doses for (a) precautionary action zone and (b) Urgent protective action zone

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Table 1: Representative releases from containment

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Keywords: EPZ, precautionary action zone, projected dose, protective actions, urgent protective action zone

References

IAEA GSR Part 7; 2015.
Goossens LH, et al. COSYMA, EUR 18826. IAEA (2013) EPR-NPP Public Protective Actions; 2001.

Abstract - 82322: Radiological impact assessment of a complex nuclear plant site using artificial neural network approach

M. K. Chatterjee, S. Murali

Radiation Safety Systems Division, Bhabha Atomic Research Centre, Trombay, Mumbai, Maharashtra, India

E-mail: [email protected]

Introduction: In case of atmospheric releases of radioactivity, suitable dispersion models are used to predict radiological impact taking the site characteristics into account. If the site is complex, atmospheric dispersion of radioactive plume is non linear. For such complex sites, large variation between the predicted and actual values of radiological parameters has generally been observed¹. In the present study, different Artificial Neural Network (ANN) architectures have been formulated for accurate prediction of gamma dose rate for complex BARC, Trombay site.

Materials and Methods: Considering the land and sea interface and with the presence of surrounding hills, BARC, Trombay site is complex in nature. During normal operation of nuclear facilities at BARC site, continuous dose rate data collected during atmospheric dispersion of ⁴¹Ar plume released from research reactors, using offline dose logging system (Gammatracer). The receptors location, meteorological data, release rates and a part of the observed dose rates are employed for designing and training the ANN architectures [shown in [Figure 1]]. Three ANN algorithms (Standard backpropagation method (backprop), Resilient backpropagation (RPorp) method and the Lavenberg-Marquardt (LM) technique) have been trained and tested to select the best network architecture for radiological impact predictions at the BARC, Trombay site. The total dataset used for the modeling comprises of 125 patterns (1000 data points) each have seven columns corresponding to the 7 inputs (downwind distance, elevation, wind speed, wind direction, temperature, stability and release rate) and one output corresponding to the dose rate in each pattern. The training set (70% of data) is used by the algorithm to learn the patterns of the data. This corresponds to ~700 data points used for training the model, whereas ~300 data points are used for testing the algorithms.

Results: After many trial and error attempts one hidden layer with the architectures 7:30:1 for backprop (7 inputs, 30 hidden nodes and 1 output), 7:20:1 for RProp and 7:12:1 for LM method was found to be optimum. The percentage of relative error computed to check the performance of the ANN models and conventional Gaussian Plume Dispersion Model (GPDM) with respect to experimentally observed data. The percent error value predicted by RProp lies in a very narrow range of values at -9% to +6%. Since RProp model returned the least uncertainty compared to all other methods, one can safely prefer to use this ANN based method within the specific range for radiological impact predictions of Trombay site. The comparison also indicates that the ANN predictions (with RProp, 7:20:1) provides more precise results compared to other conventional theoretical modeling technique.

Conclusions: Results obtained from this study shows that the ANN technique could be more useful for estimation of dose/dose rates and also to predict source term in case of very negligible chances of accidental atmospheric releases of radioactivity for BARC site. It is also an effective tool for radiological impact assessment for both normal and in emergency condition.

Figure 1: ANN architecture with Input & output parameters

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Keywords: Neural network, nuclear plant site, radiological impact assessment

Reference

Chatterjee MK, Divkar JK, Patil SS, Singh R, Pradeepkumar KS, Sharma DN. Radiat Prot Dosimetry 2013;155:483-96.

Abstract - 82345: Development of new mobile radiological assessment laboratory

R. N. Pujari, M. Harikumar, Shashank S. Saindane, Pravin Sawant, S. Murali, Probal Chaudhury

Radiation Safety Systems Division, Bhabha Atomic Research Centre, Mumbai, Maharashtra, India

Email: [email protected]

To enhance the capability for emergency preparedness and response toward any Nuclear and Radiological events, the New Mobile Radiological Assessment Laboratory (M-RAL) with added features has been developed based on our previous operational experience on similar such systems developed. New M-RAL uses highly sensitive Plastic scintillator detector, better vehicle layout to install the various state of art radiological monitoring systems, Digital Wireless Communication Network (DWCN) and has multiple choices among power systems of 12 V DC. Installation of high sensitive Plastic scintillator detectors could be helpful for detection of any orphan sources in cities, if any and also for generating the radiation baseline data of major Indian cities.

Introduction: The peaceful applications of radiation technology in the areas of power generation, healthcare, agriculture, food preservation, industry and research may have minor potential to cause any sudden occurrence of nuclear or radiological accident, that could cause large impacts on the surrounding environment. Mobile vehicle based RAL may quickly be deployed to the accident site and monitor initially the radiological status at any event of Nuclear or Radiological emergency.

Salient technical features:

Enables rapid response in the event of radiological accident or adversary act
Real-time emergency field radiation monitoring and mapping
User friendly interface, supportive graphical display

Monitoring Methodology: Different types of radiation monitoring instruments/systems are installed inside the vehicle to cover all the sides of the monitoring vehicle as shown in the [Figure 1]. GPS antenna are positioned in the vehicle to get a reliable GPS coverage. During radiological monitoring of location, the continuous dose rate data along with position coordinates are recorded at every 5 sec acquisition time and transferred to the PC.

Systems in the RAL:

The installed systems in the vehicle are classified on the basis of distinct operational systems.

· Eight Channel Counter Timer (ECCT)

· Mobile Gamma Spectrometry Systems (MGSS)

· Plastic Scintillators

· G.M. Detectors

· Alpha/Beta Continuous Air Monitor

· Personal Protective Equipment and Decontaminations agents

Digital Wireless Communication Network (DWCN): DWCN is developed for the automated data acquisition from M-RAL and the transfer of acquired data to the 'Response Centre' location for further analysis. Data acquisition and software: The data received by the 8-channel counter system and MGSS is processed by the software. Software displays the positional coordinates, route and speed of the mobile laboratory for each data acquired. After the radiological monitoring a detailed report is auto generated with statistical analysis for each location and all the data covered during the monitoring period.

Results and Discussion: M-RAL is an excellent backup under emergency preparedness, providing laboratory-scale functionality on wheels, can communicate with field response team and Response Centre for minimizing response time for action as countermeasures and thereby the impact. This capability can be applied quickly in different kinds of radiation emergency situations.

Figure 1: Actual layout of systems installed in the mobile platform along with the output screen

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Keywords: Mobile radiological monitoring, nuclear and radiological emergency, orphan source

References

Pujari, et al. Development of Mobile Radiological Impact Assessment Laboratory. NSNI; 2013.
Generic Procedures for Monitoring in a Nuclear or Radiological Emergency; IAEA-TECDOC-1092.

Abstract - 82413: Evaluation of environmental radiation monitoring points at a multi-facility nuclear site

J. K. Divkar, C. Anirudh, M. K. Chatterjee

Radiation Safety Systems Division, Bhabha Atomic Research Centre, Mumbai, Maharashtra, India

E-mail: [email protected]

Introduction: The nuclear sites are radiologically monitored by various online and offline systems. Such systems include fixed network-based radiation monitors and vehicle-based monitoring systems. The present study uses one such vehicle-based radiation surveillance method to re-evaluate the monitoring strategy of a site, to enable optimum emergency response.

Methodology: The legacy monitoring strategy of the site under study involved a survey of 35 fixed locations around the site (10:00 to 15:00 hrs). This strategy was originally framed to cover all facilities located within the site to ensure comprehensive radiological coverage. Due course of time, new facilities and additional motorable pathways were created within the site. This demanded to reconstruct/modify the monitoring strategy which will also take into account Ar-41 impact at site, routinely released in low levels from the research reactor within the site. To account for all these parameters and to ensure optimum coverage, a new strategy was formulated. This strategy divides the entire site into three distinct zones - North (NZ), Central (CZ) and South Zones (SZ). Sixty monitoring points were identified (NZ:19, CZ:28 and SZ:13). NZ and SZ would be covered in the morning hours (08:00 to 12:00 hours) and CZ would be covered in the evening hours (15:00 to 19:00 hrs) to assess the influence of routine releases based on the earlier studies¹. At each of the 60 locations, 5 to 7 dose rate data points were collected by the vehicle-based monitoring system. The data recorded over one year was analyzed and normalized values are presented.

Results and Discussions: The zone wise percentage deviation of recorded dose rate from the site average dose rate for a particular day during operation and shutdown are shown in [Figure 1]. It is reflecting that high dose rates are observed in SZ followed by CZ. This increase in the values above background in SZ is persisting for short duration (~1 hour). This high value in SZ can be attributed to the persistence of Ar-41 plume in morning time. It was also observed on the basis of research reactor operation for longer duration (~ 1 year); the average dose rate values are highest for SZ [Table 1]. The percentage Relative difference (% R.D. = [(DR_op-DR_sd) *100/DR_sd] is also higher for SZ, followed by CZ and NZ. Again, it is evident from the table that the average values for operation condition is slightly higher than shutdown condition, which indicates normal operation of the nuclear facilities have minor radiological impact at the site. In all the cases, NZ is found to be least affected throughout the study period. Hence for quick assessment of radiological impact at the site during emergency, the SZ and CZ may be prioritized over NZ.

Conclusions: Radiological impact due to normal operation of nuclear facilities is insignificant. If any, radiation accident takes place within the site even though probability is very small, the dose rate trends in CZ and SZ may be considered as representative of radiological status of the entire site for radiological impact assessment and to initiate response actions. A large data over an extended period of study would help in optimizing the monitoring points for quick radiological assessment.

Figure 1: Normalized dose rate values of different zones

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Table 1: Zone wise normalized average values (D/D_max)

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Keywords: Mobile platform, radiation monitoring, zones

Reference

Chatterjee MK, Divkar JK, Patil SS, Singh R, Pradeepkumar KS, Sharma DN. Radiat Prot Dosimetry 2013;155:483-96.

Abstract - 82465: Land use/land cover dynamics within the long term action planning zone of DAE Kalpakkam site using remote sensing and GIS analysis

R. Deepu, S. Rajiv Kumar¹, S. Chandrasekaran, C. V. Srinivas, B. Venkatraman

Environmental Assessment Division, SQRMG, IGCAR, Kalpakkam, Tamil Nadu, ¹Land Use and Cover Monitoring Division, NRSC, ISRO, Hyderabad, Telangana, India

E-mail: [email protected]

Introduction: Remote sensing is the science of gathering information about earth's surface features from a distance. The surface features captured from the satellite are processed and classified using digital image processing and classification algorithms. The LULC features frequently undergo changes due to causes like rainfall, population increase, industrialization and deforestation^[1] etc. Kalpakkam is a multi-facility DAE site on the east coast of India. Though the possibility of a nuclear emergency is very negligible, the area around the site is classified into different zones as per regulatory requirement (AERB EP5 Guidelines) and is monitored to carry out necessary emergency actions to mitigate the consequences in the event of an accident. To carry out protective actions, information like demography, infrastructure, LULC details of the area around the site are crucial. Further, it is required to analyze LULC changes for monitoring the environment.

Materials and Methods: In this work, LULC analysis is carried out in the Long term Protective Action Planning Zone around DAE site using satellite data products of Indian Satellite, Resourcesat-1 (IRS-P6), having a spatial resolution of 23.5m in the Visible & NIR spectral bands, obtained from NRSC, ISRO. The classified maps are verified using ground truth information collected from various places within the DAE site and randomly selected locations outside the site. Decadal change detection analysis has been done between the classified maps of 2005-06 & 2015-16 using GIS tools.

Results and Discussion: The level 2 classification of 30 km area around DAE site for 2005-06 & 2015-16 is shown in [Figure 1] covering a study area of 1422 sq. km. Analysis indicated that major land cover types in the LPZ are croplands (48%), water bodies (15%), built-ups (10.5%), coastal wetlands (4.5%), forests (4.7%) etc. It is found that the croplands have reduced by 7%, built ups (rural & urban) and industrial area has been increased by 4.7% & 1.6% of the total geographical area (TGA) of LPZ due to conversion of croplands & plantations into built-ups [Table 1]. The scrub forests have reduced by 3% and fallows have increased by 4% due to inter-conversion. Most of the above changes have taken place in the northern portions of DAE site due to urbanization. The scrublands have increased by 1.3% due to conversion of croplands, observed to the south of Palar river. This spatial database of the LULC in a finer detail is useful in decision support systems (DSS) for planning the long-term protective actions such as food control and for modelling the ingestion dose using atmospheric dispersion models.

Figure 1: Level 2 Classification for 2005-06 & 2015-16

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Table 1: Overall change statistics in long term action planning zone

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Keywords: Change detection, DSS GIS, emergency planning, LULC, protective actions, satellite image

Reference

Fichera CR, et al. Land Cover classification and change-detection analysis using multi-temporal remote sensed imagery and landscape metrics. Eur J Remote Sens 2012;45:1-18.

Abstract - 82472: An overview on key elements for hazard assessment for emergency preparedness and response and determining emergency planning zones and distances

S. K. Dubey, S. P. Lakshmanan, Ritu Raj, Krishna Reddy, Deepak Ojha

Directorate of Radiation Protection and Environment, Atomic Energy Regulatory Board, Anushaktinagar, Mumbai, Maharashtra, India

E-mail: [email protected]

Though the NPPs are designed robustly considering defence in depth levels, based on safety principles, arrangements must be made for emergency preparedness and response to achieve fundamental safety objective to protect people and the environment under any emergency conditions. Accordingly hazard assessment is required to be performed for planning and implementing protective actions and other response actions. Adequate knowledge and clarity is needed on the following key elements for hazard assessment: i) selection of events to be assessed, ii) estimation of core inventory of radionuclides of the release or source, iii) dispersion and deposition, iv) assessment of consequences in terms of dose or dose rate, v) protective actions required and vi) determination of planning zones and distances. In contrast to deterministic safety analysis for licensing, selection of credible events for hazard assessment for emergency preparedness should also broadly covers event not considered in design (containment failure, single failure for DECs etc.), practicality eliminated events, beyond design extension conditions, multi-unit accidents and combination of a nuclear or radiological emergency with conventional emergencies. As part of hazard assessment, all potential events that could have a consequence on the health and safety of onsite personnel or the public needs to be considered. Hazard assessment is carried out with realistic methodology using best estimate model with addressing uncertainties. However, simple and conservative methods can also be applied with the addressing its implications of conservatism on protection strategy and associated emergency arrangements. At present with the state of the art methodology magnitude of these uncertainty is significant. Based on the hazard assessment, on-site and off-site areas and locations are identified which would warrant protective actions and other response actions termed as planning zones and distances. These zones and distances are based on severe deterministic, deterministic and stochastic effects based generic criteria. In actual emergency scenario provisions for its re-adjusted are made. The assumptions on the release characteristics as a source term is the most important governing factor for the estimation of these zones and distances. Experience based on past major accidents source term is less than 3% and 10% of core inventory for Fukushima Chernobyl respectively. However these reactors were of old generation and lots of human error were there for handling such events. At present generation III reactors with advanced engineered safety features (like steel line containment, CFVS etc.), the magnitude of the source term are likely to be reduced. It is to be noted that above assumptions is applicable for large reactors. In determining the distance, both deterministic and probabilistic approaches can be used for estimating the planning distance. Deterministic approach considers the worst case scenarios along with a set of parametric studies while the probabilistic approach considers the overall risk under all possible scenarios. Robust emergency preparedness arrangements that enable prompt and effective implementation of response actions can be maintained through planning zones and distance that are identified based on detailed hazard assessment. However, these arrangements are viewed as and considered to have a certain degree of psychological burden and economic penalty and hold back efforts for sustained development supported by nuclear power. Under such circumstance, NPP can be operated without emergency planning zones (precautionary and urgent actions) as deterministic effects are not expected and response actions for reducing stochastic effects can implemented with help of ingestion and commodity planning distances (EPD and ICPD). This can be possible with advanced new generation reactors especially like small modular reactors with emergency planning areas based on source terms corresponding to the type of design and power level and its hazard assessment.

Keywords: EPD, generic criteria, hazard assessment, ICPD, PAZ, UPZ

References

IAEA. GSR-Part 7, General Safety Requirement, Preparedness and Response for a Nuclear or Radiological Emergency. IAEA; 2015.
ICRP. Radiological Protection of People and the Environment in the Event of a Large Nuclear Accident, Publication 146 (Update of ICRP Publications 109). ICRP; 2008.
IAEA. DS 504, Arrangements for Preparedness and Response for a Nuclear or Radiological Emergency (Draft for Revision of GSG 2.1). IAEA; 2021.

Abstract - 82534: Radiological mapping of emergency planning zone of Rawatbhata Site for base line data Generation

N. K. Meena, Rajpal Gill, M. K. Meena, S. Dashora, S. N. Tiwari, I. V. Saradhi¹, A. Vinod Kumar¹

Environmental Survey Laboratory, EMAD, BARC, Rawatbhata, Rajasthan, ¹Environmental Monitoring and Assessment Division, BARC, Mumbai, Maharashtra, India

E-mail: [email protected]

As a part of emergency preparedness at national level, radiological mapping of EPZ area of Rawatbhata site was carried out. Radiological mapping through road routes was carried out by a light motor vehicle and using state-of-the-art radiation monitoring Instruments installed in the vehicle. Availability of such baseline data will facilitate quick decision making during any possible radiological or nuclear emergency. Instruments are selected on the basis of environmental conditions of measurement, power requirement, size of instruments, online and offline measurement, range and time of measurement, quantities to be measure etc. Gamma Tracer, Micro-R Survey Meter, Global positioning System, Personal Radiation Detector, Identifinder and Compact Aerial Radiation Monitoring System (CARMS) were used during the survey. Detailed radiological survey EPZ area carried out enroute major roads, hospitals, temples, bus stands, major tourist destinations, residential areas, scrap yards and other accessible areas. Level of terrestrial radiation differs from place to place as the specific activity of the naturally occurring radionuclides of ²³⁸U, ²³² Th and ⁴⁰ K in the earth's crust varies. Recorded radiological dose rate data of important locations are shown in [Table 1]. Total 210 measurements were made to cover entire study area and average exposure rate during survey was 50 nGy/h with some locations showing slightly higher than natural background levels.Variation of gamma dose rates with locations is shown in [Figure 1]. MGP make Identifinder was used for acquiring gamma ray spectrum. Soil samples were collected for gamma spectrometric evaluation of natural gamma emitters at ESL RAPS as per standard procedure. The gamma spectrometric evaluation of collected samples from different locations showed presence of ⁴⁰K, ¹³⁷Cs, natural ²³⁸U and ²³²Th decay series radionuclides [Table 2].

Figure 1: Exposure rate variation observed at different locations of EPZ area

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Table 1: Average dose rate recorded at important locations

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Table 2: Radionuclides in analysed soil samples

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Keywords: Emergency, EPZ, exposure rate, radiation levels

Reference

Radiation Mapping of Kaiga Emergency Planning Zone by Mobile Monitoring Methodology, IARP Conference, 18-22 November, 2005.

Abstract - 82578: Comprehensive evaluation of radiological and mineralogical attributes of soil samples: A comparison of neutral versus vegetation land

Sanjeet S. Kaintura¹, Sarabjot Kaur², Swati Thakur¹, Pushpendra P. Singh^1,2

¹Department of Physics, Indian Institute of Technology Ropar, ²Agriculture and Water Technology Development Hub, Indian Institute of Technology Ropar, Rupnagar, Punjab, India

E-mail: [email protected]

Naturally occurring radionuclide materials (NORM) in the terrestrial environment occupy the maximum share of radiation exposure to humans. Soil is not only a source of environmental radioactivity but also a medium of radionuclide transportation from crops to the food chain. Rapid industrial growth, intensive utilization of different chemicals in pesticides and fertilizers for agronomic purposes and heavy metal (HM) contaminating soil need to be assessed. In order to investigate the natural and artificially added radioactive substances, HM composition and their impact on human health, a comparative study of soil profile of neutral and vegetation land of Ropar in the state of Punjab in India has been carried out. It should be mentioned that the vegetation land has been used extensively for farming activities while the neutral land was devoid of any human interference for more than a decade. A high resolution ultra-low background HPGe detector [Figure 1] of 33% relative efficiency was employed to investigate the activity concentration of ²³⁸U, ²³²Th and, ⁴⁰K in soil samples collected from neutral and agricultural land, and analyzed offline employing LAMPS (Linux Advanced Multi Parameter System) software. The activity concentration of ²³⁸U, ²³²Th and ⁴⁰K range from 24.65±0.56 to 50.19±0.86 Bq kg^-1, 38.62±0.73 to 74.74±1.10 Bq kg^-1, 261.33±9.94 to 360.96±10.48 Bq kg^-1, respectively for neutral land. However, for vegetation land, the activity of ²³⁸U, ²³²Th and ⁴⁰K range from 22.84±0.71 to 30.76±0.87 Bq kg^-1, 40.98±0.78 to 49.00±0.86 Bq kg^-1, 300.35±10.65 to 489.45±17.16Bqkg^-1, respectively. The mean annual effective dose for neutral land (0.08 mSv y^-1) and vegetation land (0.07 mSv y^-1) was found to be somewhat consistent with the global mean value of 0.07 mSv y^-1. The concentration of HM in both types of soil samples has been found as in order Cr > Pb > As > Hg > Cd. Potential contamination index for each HM in vegetation land has been found to be higher than the neutral land except for the Pb, indicating that vegetation land is more polluted as compared to neutral land due to human intervention.

Table 1: Statistical analysis of heavy metal content in soil samples (ppm

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The authors would like to thank the Department of Science & Technology, Government of India, for the establishment of a Technology Innovation Hub (AWaDH) at Indian Institute of Technology Ropar in the framework of National Mission on Interdisciplinary Cyber-Physical Systems (NM—ICPS).

Figure 1: Experimental setup (IIT Ropar low background measurement infrastructure)

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Figure 2. Radium equivalent activity in soil samples.

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Keywords: Effective dose, heavy metals, HPGe detector, naturally occurring radionuclide material, radioactivity

Reference

WHO/FAO. Report of the Thirty-eighth Session of the Codex Committee on Food Hygiene, Houston, USA. ALINORM 07/30/13; 2007.

Abstract - 83148: Development of vehicle mountable detection system for measurement of gamma emitters in biological/environmental samples during radiological/nuclear emergencies

Rajesh Sankhla^1,2, Suma Nair¹, Pramilla D. Sawant¹, M.S. Kulkarni^2,3

¹Radiation Safety Systems Division, ²Homi Bhabha National Institute, ³Health Physics Division, Bhabha Atomic Research Centre, Mumbai, Maharashtra, India

E-mail: [email protected]

During Nuclear/Radiological emergency situations, radioactivity may be released in the surrounding environment. The released radioactive substances are deposited on plants, soil or water and enter the food chain. During such situations, rapid screening /monitoring of foodstuffs is recommended and based on the monitoring data, further countermeasures need to be implemented to avert doses to the members of the public. Vehicle Mountable Detection System (VMDS) has been developed to improve the preparedness for rapid screening of the foodstuffs (dietary items, water, milk etc.) for the gamma emitting radionuclides during emergency situations. The developed system can be transported and deployed in the vehicle for field use or in a laboratory/room. It is incorporated with 76 mm dia. x 76 mm thick NaI(Tl) detector coupled with standalone 1k MCA, laptop. The detector shield thickness is made up of interlocked 51 mm thick lead rings provided with inner side lining of 2 mm tin & 1 mm copper. This shield combination is nearly 4 HVL for ⁴⁰K 1460 keV gamma energy. It is a compact system, having foldable stand for laptop and occupies space of 90 cm x 50 cm area for operation and the total height of the system is ~ 1m. The complete system is made portable by mounting on a trolley. The background reduction factor observed for useful gamma energy region (100-2000 keV) is 16 whereas for radio nuclide specific energy regions like ¹³¹I (230-430 keV), ¹³⁷Cs (550-750 keV) and ⁶⁰Co (1050-1450 keV) it is 17, 13 and 9, respectively. The VMDS was calibrated for wide range of sample containers like 100 mL to 1L plastic containers, sample bottle, metal pots and beverage cans found in food stores. Efficiency calibration of the system is carried out for different geometries for known amount of activity concentration of ¹³³Ba, ¹³⁷Cs and ⁶⁰Co liquid sources. [Table 1] presents the Minimum Detectable Activity (MDA) for different radionuclides in VMDS at laboratory condition (ambient dose rate of ~ 80 nSv/hr). The evaluated MDAs are below the Operational Interventional Level (OILs) (3000 BqL^-1 for ¹³¹I, 2000BqL^-1 for ¹³⁷Cs & 800 BqL^-1 for ⁶⁰Co) recommended by regulatory authority.^[1] The computed activity concentration of these radionuclides in foodstuffs can be easily compared with the OILs for further appropriate actions. Development of field deployable VMDS has strengthen the rapid estimation of gamma emitting radionuclides at affected site during emergency situations.

Figure 1: VMDS system

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Figure 2: Types of samples and counting geometries

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Figure 3: Typical source spectrum

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Table 1: Minimum detectable activity for 10 min counting time

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Keywords: Gamma emitters, OILs, radiological/nuclear emergency

References

Criteria for Planning. Preparedness and Response for Nuclear or Radiological Emergency. AERB Safety Guideline AERB/NRF/SG/EP-5 (Rev.-1); 2014.

Abstract - 83248: Application of portable liquid scintillation counter for on-field measurement of ³H

Priyanka J Reddy¹, Rajesh Sankhla^1,2

¹Radiation Safety Systems Division, Bhabha Atomic Research Centre, ²Homi Bhabha National Institute, Mumbai, Maharashtra, India

E-mail: [email protected]

Anthropogenic ³H is produced in NPPs due to activation of deuterons or as a fission product. It may get released into the environment as a result of nuclear accidents leading to its significant inventory in the environment. Once released into the environment, ³H follows hydrological cycle and contributes to human exposure e.g., through drinking water. Hence, analysis of ³H in drinking water is an essential requirement. In order to respond to emergency situation, rapid screening of the samples is a necessity and sending the samples to laboratory for analysis may be difficult due to limited access. Thus, on-field measurement of ³H will always is preferable because it helps decision makers to introduce prompt intervention measures. In the present study portable Liquid Scintillation Counting (LSC) is used to develop a screening technique for ³H measurement in water samples. Hidex Triathler is a single vial LSC that provides fast & reliable results for radioactivity measurement. Its compact size (33 cm (L) X25 cm (W) X19 cm (H)) & light weight (9kg) make it ideal for on-field measurements. Due to these features, it can be easily placed inside any mobile vehicle &transported to area near the incident site. For ³H activity estimation using LSC, quench is one of the important interferences which is influenced by the ratio of scintillator & water added to the samples & is the key point of optimal counting condition. The present study offers optimization of scintillation cocktail (V_C) to sample (V_S) volume ratio (λ) and best possible counting efficiency (CE) using minimum amount of scintillator and availability of counting vials. Experiments were conducted with two different scintillation cocktails viz., commercially available Optiphase HiSafe III (OP III) as well as Dioxane based scintillator which can be prepared instantly in the laboratory by an analyst. Dioxane based scintillator is also studied because it can be used in case of non-availability of commercial scintillators. Set of standards were prepared by mixing distilled water (DW) spiked with ³H activity (total volume 1 mL) and varying amounts of above-mentioned scintillators ranging from 0.5 – 4 mL & 0.5 – 10 mL in 7 mL and 20 mL capacity glass vials, respectively. Samples were measured in portable Hidex Triathler LSC for 5 mins counting time. It was observed that, for Dioxane based scintillator, with λ≤1 phase separation occurred and for λ≤3, the solution turned milky due to sample immiscibility and formation of emulsion. For λ=4 i.e., 4 mL V_Cand 1 mL V_S, a clear and homogenous solution was obtained. However, in case of Dioxane based scintillator, there is limitation on the sample loading capacity (20% of scintillator volume). In case of OP III scintillator, a clear and homogenous solution was obtained from λ≥2. Therefore, scintillator to sample volume ratio (4:1) is optimized for both the scintillators in case of 7 mL vials. In case of 20 mL vials, the optimized ratio of scintillator and sample is 8:1. CE obtained in the present study for these scintillators using two different sized counting vials is presented in [Table 1]. Minimum Detectable Activity (MDA) obtained for the optimized ratio for Dioxane based scintillator using 7 mL and 20 mL vials is 12 BqmL^-1 for 5 minutes counting time. In the case of OPIII scintillator, MDA corresponding to the optimized ratio is ~3.7 BqmL^-1for 7 mL vial and 5.2 BqmL^-1for 20 mL vial. The method developed was validated by analyzing spiked DW samples. The results of analysis are shown in [Table 2]. The technique is sufficiently sensitive enough to detect ³H concentration in drinking water well below the Operational Intervention Level (2x10²BqmL^-1)recommended by AERB during radiation emergencies. The system can also be used to verify whether ³H concentration in drinking water is below the guidance level (<10 BqmL^-1) as recommended by WHO corresponding to the CED of 0.1mSvy^-1.

Table 1: Counting efficiencies for dioxane based and Optiphase HiSafe III scintillator for various sample: Scintillator ratios

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Table 2: Validation of the methodology for ³measurement

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Keywords: ³H, emergency, liquid scintillation counting, sample: scintillator ratio, scintillation cocktail, triathler

Reference

Criteria for Planning. Preparedness and Response for Nuclear or Radiological Emergency. AERB Guidelines No. AERB/NRF/SG/EP-5 (Rev.1); 2014.

Abstract - 83288: Study of effects of Ar-41 activity releases on ERM readings of DSS at RR site and Kalpakkam DAE centre

N. Khandelwal, Jaydeb Mandal, S. K. Pawar

Directorate of Radiation Proportion and Environment, Atomic Energy Regulatory Board, Mumbai, Maharashtra, India

E-mail: [email protected]

Introduction: Fukushima nuclear accident raised need of reliable Real Time Online Decision Support System (RO_DSS) at NPP sites to facilitate timely implementation of suitable protective measures in public domain during nuclear and radiological emergencies. The RO_DSS is essentially a software and hardware tool intended to provide comprehensive and timely information to emergency managers on an emergent situation arising from a nuclear accident. It predicts the real time radioactive doses due to exposure pathways (such as plume dose, ground shine dose and inhalation dose) and recommends protective actions & emergency management measures to minimize the radiological consequences. Study of DSS systems installed at RR site and DAE Kalpakkam centres were carried out on two aspects: i) Regulatory review of present DSS at two NPP sites for fulfilment of regulatory requirements and their Inter comparison , ii) impact of Ar-41 releases on ERMs of DSS.

Materials and Methods: Study of RO_DSS was carried out in regards of fulfilment of regulatory requirements. Inter comparison on ERM specifications, estimated Release rates for each stability category at two release heights, Radiation field (μSv/hr) at detector positions for different scenarios at two sites was done. In addition, ERM readings of DSS were studied against Ar-41 releases at both the sites for a period of one year. Regulatory Requirements about RO_DSS: The RO_DSS comprises of hardware and software tools which utilizes real-time & forecast weather data, dispersion & deposition models, to estimate the radionuclide concentration and projected exposure to the population and provides guidance for optimum protective actions countermeasures in public domain. It should have following features. Regulatory requirements pertaining to DSS features are as below:

The distribution and placement of environmental monitoring network around NPP Site should be in such a way that movement of accidental plume is not missed under any of the possible wind directions.
The system should have communication capabilities and automatic switching of RO_DOS from normal operation mode to emergency mode.
Should be able to work on potential source term pre-estimated based on postulated accident scenarios.
Should have on-line access, assimilation and display of the environmental radiation data.
Should be able to predict the radionuclides concentrations due to noble gases, particulate and volatile etc. and radiological doses through various routes like plume shine dose, inhalation, deposited activity etc.
It should be able to predict in real-time, optimum protective counter measures to minimize the radiological consequences.
It should provide information for management of relevant information about data, plans, inventories, and emergency response actions required during accidents.
Display the event location, affected areas, population and topographical features as well as the locations of important buildings, hospitals, roads, sheltering places etc. The results of radiological impact assessment should be overlaid on GIS system.

Results and Discussion: At Kalpakkam DAE centre a total of 33 ERMs are deployed around the NPP/NFs having two rings, one inner of lower radius and another at a larger radius considering stack as centre. At RR Site, present study was carried out for effect of Ar-41 release from RAPS-1&2 on ERMs of RAPS-3&4, as these are the closest to RAPS-1&2 (Designed DSS monitors are proposed to be installed). Analysis of data indicated that both the DSS have similar types of ERM features but expected release rate of radioactivity for same dose rate at exclusion zone boundary is not same at two site in any of the weather conditions and it is normally1.3 & 2.2 times higher at Kalpakkam site than RR site at release height of 10 m & 100 m respectively the highest difference being 5.8 times. During the period of study (one year data analysis for Ar-41 release Vs ERM readings), at RR site usual and maximum values of ERM readings had been 0.15 μSv/hr & 0.48 μSv/hr and at Kalpakkam site usual and maximum values of ERM readings had been 0.31 μSv/hr & 0.65 μSv/hr which are well within the values of switching the DSS from normal mode to emergency mode. The study conclude that criteria for switching of DSS from normal mode to emergency mode is not affected by release of Ar-41 activity from RAPS-2 and MAPS.

Keywords: Ar-41, Emergency, ERM, projected exposure, dose rate, RO_DSS

References

SARCOP Deliberations and Recommendation-644, 676, 668.
Design Basis Report on Real Time Online-Decision Support System (RO_DSS) for RR Site and (ONERS-DSS) for Kalpakkam Site.
Ar-41 Releases Data and Daily ERM Readings of RAPS-1&2 and Kalpakkam DAE Centre from October-2020 to September-2021.
Radhakrishnan D, Boopathy M, Gopalakrishnan V, Rakesh PT, Chandrasekaran S, Srinivas CV, et al. Long-term trends in gamma radiation monitoring at the multi-facility nuclear site, Kalpakkam, South-India. Radiat Prot Environ 2021;44:79-91.

Abstract - 83393: Hazard assessment and emergency radiation monitoring in PFBR

N. Suriyamurthy, Vidhya Sivasailanathan, Allu Ananth

Health Physics Unit, BHAVINI, Kalpakkam, Tamil Nadu, India

E-mail: [email protected]

Introduction: PFBR is the 500 MW(e) nuclear power plant under advanced stage of commissioning. This facility presently houses MOX fuel subassemblies which necessitates the continuous radiological monitoring both for normal and potential exposure situations. The design and operation of radiation monitoring programme for planned and emergency exposure situations should be based on the hazard assessment that characterizes radiological risks in terms of magnitude, likelihood, temporal and spatial patterns of potential exposures to public. This manuscript discusses the hazard assessment performed and justified the emergency monitoring needs in PFBR.

Materials and Methods: GSR part-7^[1] set out the requirement which stipulates that hazard assessment shall be performed by adopting graded approach. Accident analysis of PFBR as underlined in the Chapter-15^[2] of FSAR indicates that the postulated severe accident is Core Disruptive Accident (CDA) which is highly improbable event (10^-6/ry) but has wider radiological consequences. Hazard assessment takes into account of both radiological hazards and non-radiological hazards. The major input for hazard assessment comes from the in-vessel and RCB source term which was estimated using computer code Origen2. This programme has listed nearly 230 radiologically significant radionuclides with 82 GWd/t of burnup. For RCB source term, eight different chemical classes of radionuclides were identified and their release quantity estimated. FPNG being gaseous in nature have 100% release probability.

Results and Discussion: Consequent to CDA, the sodium released into RCB undergoes combustion resulting in sodium aerosols formation. However, the studies indicated that the probability of sodium aerosol release into environment is an extremely low due to micron size which favors gravitational settling. Upon release to environment, radionuclides takes different exposure pathways depending on time scale of accident wherein early phase is dominated by inhalation dose from plume, cloud shine, immersion and skin contamination. Inhalation and ingestion pathways are considered for estimating the site boundary dose due to release of radionuclides to the tune of INES level-7 that could cause the wider health effects and environmental contamination. Two release points namely stack level release and ground level release were considered and radiological impact assessment was performed by adopting the methodology given in AERB/NPP/SM/RIA-1/2021. Xenon, Krypton & Iodine are the main contributors of the cloud shine dose due to their large share in source term. Considering all the exposure pathways^[3] and contributions to total dose at the end of one year (Exposure + ingestion + ground shine) at site boundary is 64.17mSv. This is within the reference level of 20-100 mSv for effective dose. As per the Annals of ICRP-103, (2007) the criteria of projected dose in emergency situations is 100 mSv cumulative in 7 days exceeding which protection actions are to be taken. No permanent relocation is envisaged under CDA. Based on hazard assessment, PFBR comes under Category-1 emergency preparedness category for which severe deterministic effects are possible in offsite domain. Emergency monitoring in PFBR: The objective of emergency radiation monitoring is to provide accurate and timely data, to assist decision makers on the need for protective actions, to provide the information for protection of emergency workers and to inform the public on degree of hazards. Early phase of emergency of reactor emergency poses challenges since the protective action decision making is based on plant parameters and therefore, an operator can rely on decision support system to make use of modeling for prediction. Use of plant parameters for protective action can be used only when each plant parameter (EAL) is linked to projected dose and meet the generic criteria. The magnitude of dose rate which is a primary concern in early phase can be known from the 24 Autonomous Data Monitoring system fixed within the site perimeter. In case of intermediate phase, the protective actions decisions are taken based on detailed field monitoring performed by qualified personnel corresponding to OIL values that are trigger values for appropriate protective action. PFBR uses the default OIL values given by IAEA (4). Sampling, analysis and monitoring of food, water and milk are performed to characterize the situation. These data are useful in verifying or adjusting the protective actions already implemented. Four dedicated environmental monitors equipped with NaI(Tl) detector are continuous feed the radiological status to MCR.

Keywords: Hazard assessment, monitoring, nuclear emergency, PFBR

References

IAEA. Part 7. GSR; 2015.
FSAR. Ch. 15. FSAR; 2010.
Site Boundary Dose Estimate for PFBR; 2022.
Criteria for Use in Preparedness and Response for Nuclear or Radiological Emergency, GSG-2.

Abstract - 83469: Development of a QGIS plugin for decision support system in radiological emergencies

Srividya Subramanian, Manish K. Mishra¹, Shashank Saindane², Archana Shirke

Department of Information Technology, Fr. C. Rodrigues Institute of Technology, Navi Mumbai, ¹Environmental Monitoring and Assessment Division, Bhabha Atomic Research Centre, ²Radiation Safety Systems Division, Bhabha Atomic Research Centre, Mumbai, Maharashtra, India

E-mail: [email protected]

Radiological incidences may lead to an undesired radiation exposure to human population and the environment. Decision Support Systems (DSS) play a significant role in emergency preparedness, execution of prompt response measures and consequence mitigation. This has become even more important after the Fukushima accident.^[1] Identification of the direction in which the radioactive plume travels and recommending the appropriate safety measures is a crucial functionality of these systems. This calls for an analysis of spatial data of the region, which is best managed by Geographical Information Systems (GIS). QGIS, previously known as Quantum GIS, is a free and open-source (FOSS) software developed and maintained by dedicated volunteers. This paper throws light on the development aspects of a QGIS plugin (tool) where a user can specify a centre point and radius to obtain 16 wind-rose sectors. The spatial data and shortest-route within these sectors can be queried to obtain relevant information. Shortest path calculation is carried out using Dijkstra's algorithm. The tool is developed using Python programming language. The input data for this tool is a vector shapefile,^[2] or a GPKG file which contains spatial data in the form of point, lines and polygons. A suitable file consists of point data of villages, towns, hospitals and schools overlayed on a region. The tool does not require input data verification; the data can be generic in nature. Furthermore, it works on all Coordinate/Projected Reference Systems (CRS/PRS) seamlessly. The tool can be easily integrated into QGIS, and all operations will be performed on the map canvas. The centre of the wind-rose is recorded automatically from the QGIS canvas, where the user clicks. User can provide the desired radius, if not a default value of 0.1 map unit (CRS) is taken. The 16 directional sectors are rendered, which is followed by sector selection to obtain the point data present in it. To accomplish this, the sector click coordinates are resolved to a sector number between 0 and 15. Calculation of angle between mouse-click and horizontal X-axis is given in equation (1) and estimation of sector number from angle is given in equation (2).

Where (x, y) is the mouse-click coordinate, (x_c, y_c) is the circle centre, θ is the angle between the horizontal X-axis and the mouse-click coordinate, and nis a sector number in the range 0-15. An area join is carried out between the identified sector and the point data shapefile to obtain common features. The names of these points are then displayed. This tool was developed for QGIS ver. 3.16 (nicknamed Hannover), but it also runs smoothly on the latest releases of QGIS. The tool can be loaded into the QGIS environment via the Python Console menu. The tool's minimalistic User Interface (UI) was developed using PyQt5 – a Python binding of the Qt GUI toolkit. [Figure 1] demonstrates how the tool queries the data in the selected sector (highlighted in blue). While the tool internally uses 0-15 numbering to identify sectors, the user is shown the alphabetical codes to its corresponding direction. A QGIS tool to render, query data and find shortest-route from 16 directional sectors for a specified radius was developed successfully. This tool can be used to carry out spatial data analysis and supplement DSS for radiological emergency management.

Figure 1: Querying location points in selected sector

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Keywords: Emergency management, geographical information systems, QGIS

References

Callen J, Homma T. Lessons learned in protection of the public for the accident at the Fukushima Daiichi NPP. Health Phys 2017;112:550-9.
ESRI. ESRI Shapefile Technical Description. ESRI White Paper; 1998.

Abstract - 86411: Application of machine learning algorithms in nuclear forensic analysis

Jis Romal Jose, V. Baraiya Sagarbhai, Sreekanth Bathula, Mukesh Sharma, Suchismita Mishra¹, Anilkumar S. Pillai¹, Probal Chaudhury

Radiation Safety Systems Division, BARC, ¹Environmental Monitoring and Assessment Division, BARC, Mumbai, Maharashtra, India

E-mail: [email protected]

Introduction: Illicit trafficking of nuclear and other radioactive materials is one of the major concerns for the global security. Nuclear forensics is emerged as a methodology for identifying the origin of the intercepted materials in the unauthorized events. Nuclear forensic analysis involves the measurement of the signatures of the intercepted material and investigation of their similarity with the reference information. The similarity investigation is a class of multivariate analysis problem. This paper discusses the application of machine learning (ML) algorithms as an effective method for the multivariate analysis in nuclear forensic.

Methodology: ML algorithms are described as learning a target function f that best maps input variables X to an output variable Y. ML algorithms are classified into different groups based on how f is trained. Supervised Learning is the type of machine learning in which f is trained using labelled training data. Classification algorithm is a class of Supervised Learning technique, which takes a set of training observations (x₁,y₁;....(x_n, y_n) to build f. Here x_i denotes set of variables pertaining to a sample (signatures in case of nuclear forensic) and y_i denotes the sample label (origin of the sample). Classification algorithms are appropriate for the multivariate analysis in nuclear forensics to identify the origin of the intercepted material on the basis of training data in the nuclear forensic library (reference data). The output of the algorithms provides the prediction probability associated with each label for a given input data. The final qualitative prediction result is obtained by finding the label with highest probability. Various classification algorithms were attempted with different sets of nuclear forensic data available in the open literature. The performance of the algorithms was evaluated by the prediction accuracy of the algorithm. Prediction accuracy represents the number of correct prediction rate on the validation dataset. Four classification algorithms such as Artificial Neural Network (ANN), Decision tree classification (DT), Random Forest Classification (RF), and Gaussian Naïve Bayes Classifier (GNB) were found to give decent prediction accuracy. The present work shows the performance evaluation of the classification algorithms using signatures of spent fuel data. A subset of Spent Fuel Isotopic Composition (SFCOMPO), an open source international database^[1] for spent nuclear fuels, is used for the study. [Table 1] shows the summary of the data used in the study which comprises of 15 isotopic compositions from 6 different reactor types with 20 samples each. The classification algorithms were built, trained and tested in Python using an open source library called 'Sklearn'. ANN was built with ReLU activation function, Stochastic Gradient Descent optimiser, and four hidden layers. DT and RF were built with Gini impurity criterion. The algorithms were trained with 70% of the SFCOMPO data and remaining 30% of the data was used for validating it.

Results and Discussion: [Table 2] shows the prediction accuracy of the ML classification algorithms for the spent fuel data. The studied algorithms show good prediction accuracy and hence can be effectively used for supporting nuclear forensic investigation. The prediction accuracy largely depends upon the size and quality of the training data. Accuracy can be improved by increasing the number of samples in the reference database and including more forensic signatures in the analysis.

Table 1: Summary of Spent Fuel Isotopic Composition data used in the present work

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Table 2: Prediction accuracy of different machine learning classification algorithms

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Keywords: Classification algorithm, machine learning, nuclear forensic

Reference

NEA. SFCOMPO-Spent Fuel Isotopic Composition Database. NEA; 2015.

Figures

[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7], [Figure 8], [Figure 9], [Figure 10], [Figure 11], [Figure 12], [Figure 13], [Figure 14], [Figure 15]

Tables

[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6], [Table 7], [Table 8], [Table 9], [Table 10], [Table 11], [Table 12], [Table 13], [Table 14], [Table 15]

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