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Safety Management during Remediation Activities at the SNF and RW Temporary Storage Site at Andreeva Bay

Jane Smith-Briggs, RWE NUKEM, UK

A. P. Vasiliev, O.M.Minaev, International Centre for Environmental Safety, Minatom of Russia

SNIP - Building Code CP - Code practice EIA - environmental impact assessment EP - environmental protection IPM - individual protection means NPI - nuclear power installation NRB-99 - Radiation Safety Standard (of the Russian Federation; as of 1999) OSPORB-99 - Basic Sanitary Radiation Safety Regulations (of the RF; as of 1999) RNDC - reference non-dangerous content PSAR - preliminary safety analysis report RW - radioactive waste SAR - safety analysis report SFA - spent fuel assembly SNF - spent nuclear fuel SPORO-2002 - Sanitary Regulations of Radioactive Waste Treatment (of the RF; as of 2002) TLV - threshold level value TSS - temporary storage site 1. The typical project implementation breakdown for Andreeva Bay remediation activities Nearly all remediation tasks for Andreeva Bay share the same scope of work that consists of three subsequent stages. Stage 1. Preliminary survey The purpose of this stage is to make an assessment, both qualitative and quantitative (device-based), of the current state of the entity and its environment and to find out the most dangerous loci/points. The results of this stage will be the initial data for the main project work, i.e. the so-called “investment project cycle”. Stage 2. Design work In Russia, investment project cycles are commonly divided into the following sub-stages:

• Declaration (application) of intention; • Investment justification (“OBIN”); • Design documentation (inclusive of the part subject to approval).

Stage 3. On-site project implementation process The following safety management activities will be performed within the project implementation stages.

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Preliminary survey stage In the preparation of the survey, safety management is ensured through assessment of the integral dose rate that personnel are liable to when performing the survey. This assessment is to be done according to the Programme Methodology and the Operational Manual. Based on it, the routes and the sequence of the operations will be planned, IPM and associated equipment selected and protective measures developed in order that the dose rates do not exceed the acceptable limits. The amount of the radioactive waste to be accumulated will be estimated and an appropriate handling procedure developed as a part of the environmental safety analysis. The Program- Methodology and the Operational Manual of activities undergo an obligatory coordination procedure in supervisory authorities (Gossanepidnadzor, nuclear and radiation safety inspection, state environmental control). Measures for safety provisions developed during the preparation process are being implemented in the course of the survey conducting and if necessary amendments are made. The activities themselves are implemented with regular control of supervisory authorities’ representatives. Project design stage When preparing the Declaration (Application) of Intention, environmental safety analysis will be done as a qualitative per-component estimation of the impact that a technological process (object) will have on the environment. The amount of contaminating substance produced under normal conditions will be assessed. Possible accidents will also be analysed, how probable they are, their grades and duration of the impact. Disposition of the waste generated will be described briefly along with its feasibility and practicality. There is no regulatory requirement for a personnel safety analysis at this stage. The Preliminary Safety Analysis Report (PSAR) and the Environmental Impact Assessment (EIA) section will be developed within the preparation of the Investment Justification. The Safety Analysis Report (SAR) and the Environmental Protection (EP) section are subject to approval within the detailed (working) design documentation. At present, there is no regulatory document prescribing the content of PSAR and SAR reports on the type of facilities similar to those located in Andreeva Bay site. However, reference can be made to the following Russian GAN regulatory documents:

• Requirements for the contents of a radiation source safety justification report (NP-039-02)

• Requirements for a safety justification report on ship nuclear power plants (NP-023-2000)

In SAR, at least the following aspects should be considered (as appropriated in the following guideline documents):

1. Impact factors affecting on personnel, population and environment 2. Dimensions, outlines and specifics of controlled and monitoring areas 3. Basic safety provision principles 4. Description and characteristics of physical protection barriers 5. Safety limits and conditions for implementation activities (operation) 6. Description and characterization of safety important systems 7. Description of radiation safety and monitoring system

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8. Description of physical protection system 9. Description of fire safety system 10. Estimates of operational dose rates 11. Analysis of plausible accidents and emergency preparedness 12. Quality assurance

The scope and content of an environmental safety analysis for different investment project cycle stages is subject to the following documents issued by RF GOSSTROY (State Construction Committee):

1. Practical Guideline Supplement to CP 11-101-95 on developing the Environmental Impact Assessment section in justification of investments in civil and industrial construction contains requirements to environmental assessment to be developed as a part of Declaration of Intention and to EIA as a part of Investment Justification.

2. Guideline Supplement to SNiP 11-01-95 on developing the section on Environmental Protection contains requirements to EP to be developed within the frame of Detailed design documentation which is a subject of regulatory approval.

Among western regulating documents for Environmental Impact Assessment (EIA) the following ones contain general requirements: EC Directives 85/337/EEC and 97/11/EC as well as Guidance on EIA Screening, Guidance on EIA Scoping, Guidance on EIA EIS Analysis as of 2001. Comparative analysis has demonstrated that the requirements for the content and the development procedure of the Russian and western EIA standards have no cardinal difference. Generally, the following aspects must be considered in an environmental safety analysis:

• Assessment of current environmental conditions in the site of planned activities or facility location,

• Inventory and estimation of expected environmental impact from the facility, • Analysis of plausible accidents, e.g. as a risk assessment, • Assessment of arrangements for accidents prevention and for reducing the

environmental impact as low as admitted by regulatory requirements • Situation change forecast for expected facility area.

Such an analysis should contain comparison with available engineering alternatives, including no-work or no-facility location options. The following objects that could be affected may be considered within the course of assessment:

• Land resources, i.e. soil layer, landscape, and depths, • Air basin and acoustic medium, • Surface pools and aquifers, • Guarded environmental areas, • Agriculture and natural use of the environment, • Guarded cultural objects, • Demographic and socio-economic situation, • Transport and economic infrastructure.

An obligatory requirement is that an environmental monitoring system should be developed based on EIA results.

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On-site implementation stage During on-site activities, the safety arrangements developed in the design stage will be implemented. No on-line analysis of situation changes is envisaged for correction of activities. 2. The role of risk assessment for the safety analysis Risk assessment can be, along with other procedures, a part of both personnel and environmental safety analysis. Its conduction could be carried out on the basis of respective regulatory document or (in case the one is not available) according to an established practice. As a rule, risk assessment is used in the analysis of plausible accidents. Also, it may sometimes be used as well in the analysis of after-effects under standard conditions when the “dose rate (exposure time)–effect” dependence is valid. Normally no risk assessment is done when analyzing personnel safety as part of Programme Methodology and Operational Manual. It is not required that risk assessment should be performed in the preparation of PSAR/ EIA. For instance, it is envisaged in document NP-039-02 (EIA for radiation sources) that risk assessment should be performed in the analysis of accident situations. In document NP-023-2000 (EIA for ship nuclear power installations), it is envisaged that deterministic analysis methods should be applied in accident analysis. Qualitative risk assessment is allowed in the environmental assessment part of a Declaration of Intention. A full-scale risk assessment is necessary to be included in the EIA report. In the preparation of the EP section, risk assessment procedures are used to be able to forecast changes in the environment that can be caused by a specific technological process or facility being developed. The EIA process and environmental safety arrangements are discussed in details in other presentations to this seminar. That is why main emphasis is laid in this presentation on personnel safety, inclusive of risk analysis at the preliminary survey stage. It must be stressed that the above order of safety assessment and substantiation document development is to be applied for the facilities or technological processes currently under development. This order is not quite in line with the decommissioning/remediation of the closed-down facilities which are in an emergency state now. The main difference is that an emergency facility contaminates the environment already, and the safety barriers are being deteriorating with time and escalate the contamination. Degrading Building structures bring up more emergency risk increase and affect the environment in a salvo-like way. Therefore, in the restriction and reduction of the environmental impact very much importance rests with the time needed to develop and implement a project. A rather different order is necessary to develop project documentation and substantiate safety for work at emergency facilities that would ensure the investment and design phase to be rapidly passed. However, as for the time being such an order of documentation development has yet to be established.

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3. The Andreeva Bay survey stage Considerable amounts of data on the state of facilities and the environment, including personnel and environmental safety analysis, are necessary to start the main project work. Specifically, Andreeva Bay remediation tasks feature a number of peculiarities.

1. Information on the current state of facilities and the territory is either lacking or extremely incoherent. This applies especially for the state of the SNF and RW and their protective barriers.

2. This lacking or vagueness of data begets the necessity in large amounts of data to be obtained in the preliminary survey.

3. Preliminary survey activities are performed in rooms or on the territory where high degrees of radioactivity are registered. Also, areas where the survey will be conducted feature complex relief, irregularly scattered things, debris, basement and other void rooms beneath the surface level, unstable structures, etc. Thus, considerable labour costs, high radiation and traumatic rists are characteristic of those activities.

4. The incoherentness or lacking in data encumbers furthermore the planning of survey activities and the quantitative estimation of labour costs and liable risks.

5. Accidents are liable to occur during the survey because of human errors, equipment malfunctions or various external factors capable of affecting the environment and deteriorating the current environmental situation at the TSS.

4. The safety management system The issue of establishing a safety management system (i.e. a system for analysing, monitoring and ensuring personnel safety) for this particular situation seems to be uttermost urgent. According to general control theory, safety management includes the following procedures:

• Identification of danger (threat) factors, • Assessment of their significance and probabilities, • Assessment of after-effects, • Elaboration of arrangements for reduction of the probabilities of threats or seriousness

of the after-effects, based on available resources and opportunities, • Assessment of the efficiency of the arrangements, • Establishment of a set of technical and organizational arrangements to ensure safety, • Implementation of the arrangements.

In connection with the personnel safety management at the stage of Preliminary Survey, the following items should in the first place be referred to as the resources, opportunities and procedures that enable specific arrangements to be planned and carried out in order to reduce the after-effects of an impact:

• Dosimetric inspection and radiation monitoring tools, • Individual protection means (IPM) and arrangements for labour protection and overall

industrial safety, • Illumination and ventilation equipment, etc, • Means and arrangements for electric safety, • Means and arrangements for fire protection, • Special devices, equipment and tools for on-site work,

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• Development and optimisation of operations sequence, • Planning and optimising routes, • Assessment of radwaste amount and development of radwaste handling procedure.

The process of managing safety can have both qualitative and quantitative features. At a first approach, all estimates (concerning hazards, consequences, protection measures) are obtained as experts’ judgements in qualitative categories. In the quantitative approach, it is the deterministic as well as probabilistic analysis that can be used. In a deterministic analysis, quantitative categories of damage are applied without regard of respective event probabilities. Such analysis is typically aimed at confirming in a standard operational mode the conformity of hazard levels to regulatory requirements. Risk as a factor of danger assessment and, respectively, the probabilistic approach are used in analysing possible accidents. Risks are understood to be the probabilities of established quantitative categories of damage. A noteworthy procedure can be HAZOP presented by UK experts at the 2002 Oxford workshop. This procedure is an intermediate agency between the quantitative and qualitative approaches to safety analysis. Safety parameter assessment is performed by an expert team as a common consistent opinion on threats, after-effects and respective arrangements, based on the ranking and estimations according to a specific scale. In Russia, similar procedures are used for risk management only. These assessment procedures are not used for technical safety issues and it seems unlikely that estimates obtained with them will be accepted by safety regulating authorities. The probabilistic approach, i.e. risk assessment, is understood to be the most expedient for the personnel safety management system to be developed for the Andreeva Bay activities. 5. Some hazard factors affecting Andreeva Bay remediation activities Some examples are given below regarding danger factors that were revealed during the preparation and implementation of specific inspection activities as well as evident arrangements for their minimisation. Impact on personnel Dry storage units The following factors need to be considered:

• Radioactive aerosols and contamination, • Weak lighting, • Over-floor cell tube parts with heads, • Hazardous radiation situation incurred by irradiation from SFA cells; Pγ ~5 mSv/h.

The γ-background values measured were several times exceeding the estimated ones. Additional experiments were performed to define additional γ-ray source – corrosion deposits on the walls of cell steel pipes containing caesium. A possibility exists therefore to remove the deposits and reduce substantially (3-5 times) the radioactive background to enable elongation of the period of safe operation for personnel. Typical situation is given on Fig. 1.

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Fig 1. DSU: Cells containing SFA SRW storage pad

Fig 2. View of SRW storage pad

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Fig 3. 3D-picture of SRW located at SRW pad The SRW pad has the following features:

• Radioactive aerosols and contamination, • Multi-row location of SRW containers with no fixation, • Bulks of canisters and concrete beams, • Hazardous radiation situation: Pγ up to 30 mSv/h.

In the summer of 2003, a radiation survey was performed at the SRW pad that resulted in the discovery of individual zones where high γ-background was found. These local sources may be either removed or screened under remediation activities planned for the summer of 2004, which will allow the overall radioactive background to be reduced. Building 5 Around the building:

• Complex relief around the building with pits and hollows nearby the basement, • Hazardous radiation situation caused by basement concrete contamination; Pγ up to 15

mSv/h. Inside the building:

• Hazardous radiation situation; Pγ up to 10 mSv/h, • Radioactive aerosols, dust and contaminated spots,

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• No lighting.

Fig. 4.

• Heaped-up concrete beams imminent to collapse

Fig. 5.

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• Wall brackets removed from above the pools, which brings up the threat of falling

down into heavily contaminated 6.5 meter-deep pools

Fig. 6.

• Difficult access to operational hall The hatchway between the operational hall and the transport corridor has been substantially widened during emergent SNF removal from Building 5. An LRW purification installation located inside the building blocks the passage on one side of the hatchway and the protective cabin from which the crane was controlled, blocks it on the other side. The passage between the cabin and the wall is so narrow that a man can hardly get through without contaminating his overall. This can be avoided by constructing bridges through the hatchway, thus allowing free passage to be possible and devices carried to the pools. Another possible risk-reducing arrangement would be in providing sufficient illumination, though temporarily. General problem There may be zones with high-level contamination under the heaped-up beams. Impact on the environment During the survey, liquid and solid RW will be accumulated, which makes it necessary to have appropriate storage containers ready.

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6. Safety management at the preliminary survey stage Analysis and monitoring It is understood that the safety analysis and justification work should be arranged in the following way. In the development of methodology and procedures for conducting surveys, a logic model will be built for the risks liable to occur during the survey. The model takes into account all data available for the moment. However, the model is being updated in the course of further detalisation and change of situation, accumulation of data in order to allow further assessment iterations. Results of the estimates serve the basis for adjusting planned activities and developing preventive actions so as to minimize the risks under specific conditions. A three-dimensional model of the facility to be surveyed may be of great importance when simulating liable accidents. This three-dimensional model may basically be fused as an analytic and computational application with the logic risk model to build single unified software. The use of ALARA principle At present, Russian regulations do not have a requirement for impact parameters reduction under reasonably achievable conditions when those parameters are within the regulatory limits. This leads to the practice that all terminal conditions featuring damage values that are in compliance with the regulatory requirements are considered in a risk model as acceptable. Using the ALARA principle seems to be opportune when assessing radiation impact risks for personnel. The single terminal condition or a group of allied conditions that ensure the minimally possible (under reasonable conditions) radiation risk value will be accounted as acceptable. The experience gained by international experts in practical ALARA applications would be very much of service in the defining of “reasonability” criteria. At Fig. 7, a possible Building 5 operational hall inspection route is displayed. Yellow arrows mark the actual inspection route that was gone in the preliminary inspection. The criteria applied for route selection are as follows: radiation field position, location of heaped-up elements and removed wall-brackets; rickety concrete beam piles; condition of external metallic staircase. Safety assurance As has been mentioned, the safety monitoring and analysis process will result in a set of arrangements for impact after-effect remediation. Implementation of these arrangements (i.e. the safety assurance process) should be performed with regard to the material resources of the existing Andreeva site safety system and those being developed in the framework of DTI-funded project “TASK 4. Radiation Safety Assurance during Remediation Activities at the Technical Area of the TSS in Andreeva Bay”.

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Fig 7.

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7. Risk model application during further work stages (design and on-site activities) Risk and 3D facility models developed during the preparation and implementation of the preliminary survey can further be used in the development for personnel and environmental safety analysis and justification. The use of already developed and “tried” models will enable the effort required for safety analysis to be reduced and the accuracy of the analysis to be increased. It is expected to be useful if the risk models developed during the preceding project stages (the survey and the project development) are applied in the on-site work. Periodic iterative risk assessments with regard to changing situation to assist timely and adequate managerial and technical decision-making will ensure efficient monitoring and safety management. 8. A brief description of the legal basis to be applied The above risk assessment process is based on a number of regulations that state what impacts on personnel and the environment are permitted. In Russia, the impact on the environment is normally regulated according to the sanitary hygienic rule, i.e. what is well for man is well for other recipients, too. The basic regulatory documents applied in the sphere of safety management are presented below with some of the regulations as a reference. Radiation safety Human impact

1. Radiation Safety Standard (NRB-99) 2. Basic Sanitary Radiation Safety Regulations (OSPORB-99).

Example: Effective personnel dose rate is 20 mSv per year in the average within any subsequent 5 years, but not more than 50 mSv per year. Environmental impact

1. Radiation Safety Standard (NRB-99) 2. Basic Sanitary Radiation Safety Regulations (OSPORB-99). 3. Sanitary Regulations of Radioactive Waste Treatment (SPORO-2002)

Examples: 1. Effective population dose rate is 1 mSv per year in the average within any subsequent 5 years, but not more than 5 mSv per year. 2. Solid RW classification against incurred radioactive contamination.

Specific activity, kBq/kg Waste category Beta-active nuclides Alpha-active nuclides

(excluding transuranics) Transuranic nuclides

Low-level 5*102 to 104 5*101 to 103 5 to 102 Medium-level 104 to 107 103 to 106 102 to 105 High-level over 107 over 106 over 105

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Chemical safety Human impact Hygienic norms for TLV and RNDC of harmful substances in working area air Examples: Non-organic dust: TLV= 4 mg/m3; Acetylene: RNDC=1.5 mg/m3. Environmental impact Hygienic norms for TLV and RNDC of harmful substances in engineering site air and industrial pond water. Example Air Ozone: TLV= 0.1 mg/m3. Electric safety

1. Electric installation design code. 2. Electric installations operational manuals. 3. Enterprise instructions.

Fire safety Human impact

1. Fire safety rules of the Russian Federation (PPB 01-93). 2. Enterprise fire protection. General requirements (NPB 201-96). 3. Enterprise instructions

Impact depends also on toxic properties of burning products (i.e. chemical safety norms must be used). Environmental impact Impact depends also on toxic properties of burning products (i.e. chemical safety norms must be used). Traumatic safety The procedures and standards of a specific enterprise to be applied. 9. A brief description of the methodical basis Methodologies applied The methodology of probabilistic safety analysis (PSA) can be used to build a logic risk model. Event chains are represented as “event trees”. Structural system reliability and personnel error analyses can be performed as the construction and calculation along “failure trees”.

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Air pollution analysis should be performed according to the “Methodology of Calculating Concentration of Malign Substances in Industrial Releases” (OND-86). Air contamination analysis should be performed according to Methodology DV-98 and “Guidelines on Calculations of Air Radiation Situation and Expected Population Exposure during Short-Time Radioactive Releases in the Atmosphere” (MPA-98). The Methodology DV-98 allows of simulating the spreading in air of permanently released substances under normal conditions. The Methodology MPA-98 allows of simulating a burst-like (accidental) release without implication of an explosion. The methodical basis for just-a-dose contamination assessments is provided by the methodologies DV-98 and MPA-98. Unique methodologies have been developed in Russia to enable personnel health risk assessment through a recipient’s absorbed dose and pollution exposure time. Software used There is presently a considerable amount of software products for building risk models with respect to “event trees”–“failure trees”, like RISK SPECTRUM by RELCON AB (Sweden) and SAPHIRE by NRC (USA). Software RISK was developed in Russia under the Minatom request. There is a number of products based on methodologies OND-86, DV-98, MPA-98 in the Russian software marketplace, like a software product by GARANT that employs all the three above methodologies with respect to building situation, land relief, digital mapping, etc. 10. New project proposal Regarding all the above, the proposal of a new project is thus being suggested. The objective of the new project will be to have a system for personnel safety management developed and its functioning throughout the entire Andreeva site remediation project ensured. According to our opinion, such a system should be unified and able to ensure safe operations within any Andreeva Bay-related project. The essence of the project is to enable the following activities:

1. Inventory-taking and establishment of a regulating basis for safety management 2. Establishment of a program-methodical basis that would enable safety monitoring and

analysis to be carried out 3. Development of simulation models and arrangement of safety analysis and protection

optimisation by means of those models for different projects. It is important to ensure continuity and consequentiality of those activities during the implementation of each individual project. Establishment of an archive of models

4. Development of a number of technical guides on safety management At present, safety management and risk assessment are envisaged within each individual project. Groups of experts are involved to perform those activities. Obviously, different professional background levels may be observed for such groups as well as different methodical approaches, especially regarding the fact that no strict regulation is available in

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Russia for those procedures. These differences can bring up problems for western managers’ and experts’ apprehension of the results of assessments. (To prevent such problems is apparently one of the missions of this workshop). It is also principally impossible, in the safety analysis under a specific project, to ensure a systematic approach to safety management, i.e. to enable interfaces with the activities performed and the resources employed under other projects. It is expected that all necessary analysis and assessments could be performed by task groups established within the new project. The generic regulatory base as well as unified methodical and software bases would be applied in those activities. In principle, development of a safety management system could be envisaged within the activities to be performed under Task 4. However, there is a major difficulty, namely that the variety of problems to be faced within this project has not been ascertained yet. Besides, there are presently no employees in SevRAO with adequate professional background and expertise in this very specific area. On the other hand, as has already been mentioned, the resources of the existing safety management system and those being developed under Task 4 will be utilized to provide sufficient safety assurance. Therefore, one of the results to be gained through this project could be a list of necessary equipment, tools, etc which would be the “initial data” for Task 4 and provide for the development of the systems for labour, radiation and environmental safety at the Andreeva Bay TSS. It should also be pointed out that the project proposed has a major difference compared with other Andreeva-related efforts ongoing or planned. It is expected that joint workgroups will be created of Russian and western experts to work within, at least, Tasks 1, 2 and 4. This order of work will predetermine an exchange of knowledge and experience and ensure that western and Russian approaches could be taken into account, on one hand, and that the project implementation process is transparent for western experts, on the other. Results of the project could also be used in the preparation of substantiation documents for licensing purposes as well as in the detailing of personnel health insurance agreements and liability for possible damage. The imaging of project results can be facilitated by means of an information system that will be developed within project TASK 6 "Integral Database on Andreeva Bay TSS Rehabilitation Activities to be funded through the DTI". Another important project result could be the development of a document that would regulate the establishment and application of a safety management system for the decommissioning of radiation-hazardous objects and rehabilitation of contaminated areas. Such a document could be submitted to Minatom of Russia for approval as a technical regulating document. Besides, in the framework of this project a document could be prepared for regulating project documentation development and safety justification for extremely dangerous emergency objects and that would facilitate the rapid running of the investment and design phase.