THE CHERNOBYL REMEDIATION PROGRAMME
PENDING ISSUES AND RISKS 

Xavier GORGE
SGN 1, rue des H‚rons
Montigny-le-Bretonneux
78182 Saint-Quentin-en-Yvelines
France
Tel.: 33.1.39.48.60.51 - Fax.: 33.1.39.48.77.27 

After five years of preliminary studies and preparation, the Chernobyl remediation Programme is entering into an active phase. In '98, will start the implementation of safety improvements on reactor 3 and the construction of a new spent fuel storage facility and of a liquid waste treatment facility, financed by the Nuclear Safety Account managed by EBRD. In the same time, the TACIS-financed projects, led by the European On Site Assistance Team, and the Shelter Implementation Programme, administrated by EBRD, will be launched. 

But, due to the lack of in-depth and systematic studies, key-issues remain to be solved: 

• The overall coherency and logic of the Programme has not been, at this stage, fully demonstrated: given the duration of the remediation activities, the establishment of a long-term Master Plan, fully integrated, is mandatory; 
• The quantity of waste to be managed on the site during the remediation operations is very important; a specific waste management scheme is urgently needed, before the start of any activity likely to handle waste; 
• The remediation Programme will require a strong and lasting logistical support: data base and documentation management, communication, health physics, utilities, on-site support. These logistical support should be integrated and coordinated with the various projects and operational activities; 
• The overall contractual and legal scheme, mandatory to anticipate any potential situation, including an accidental situation, should be carefully studied, with acceptable coverage for all the actors; 
• The procedures for the licensing of the tasks, activities and projects of the Programme should be studied and established, with a clear definition of the safety objectives and criterias, and of the applicable regulations, with a detailed examination of the safety case of each sub-task, and with an on-site follow-up of the operational activities; 
• A clear strategy of the international and Ukrainian authorities concerning the involvement of the local engineering firms, suppliers and contractors, in the near future and in the long term. A local development plan is needed to allow smooth economical transition; 
• Lastly, a strong and day-to-day coordination of the various international, bilateral and Ukrainian projects is mandatory. 

These issues need to be tackled before the start of important and irreversible on-site activities. Urgent and obvious needs could be part of a specific assistance programme, to be implemented within the next months.

INTRODUCTION 

The Chernobyl accident, with the lives it cost and the damages it caused to the environment, has deeply undermined public trust in the RBMK technology and in the USSR industry and has, by extension, shaken the reputation of the whole world nuclear industry. 

Since then, much has been done within the nuclear community in order to improve the safety of this kind of reactor and ward off the risk of a new Chernobyl; but the remains of the destroyed reactor and the waste accumulated in the exclusion zone still present an important risk for the environment and for the neighbouring populations. 

After several years of preliminary studies, it is now agreed, among the major nuclear nations, that, to recover the trust of the public, the nuclear industry must show its ability to prevent any potential accident arising from the destroyed reactor, to clean up the contaminated areas and to treat and safely store the waste accumulated after the accident. 

'97 has seen the first on site actions, financed through bilateral agreements, in the framework of the Nuclear Safety Account, administered by the European Bank for Reconstruction and Development, or financed by the European Commission, through the TACIS Programme. 

'98 will see the launching of the most important and innovative part of the remediation Programme, with the first projects included in the Shelter Implementation Programme. 

But some important and complex issues remain to be tackled, in order to insure Ukraine and the donating nations of the effective and smooth progress of the entire Programme. 

In early 1992, soon after the independence of Ukraine, French scientists went to visit Chernobyl and they came back convinced that the European countries should offer their help for the construction of a new protective shield to be installed around the first one. 

During the spring of'92, a French civil engineering company, BOUYGUES was working with SGN on a proposal for a new "shelter" with the cooperation of Ukrainian and Russian organizations and institutes. Given the complexity of the issue and the risks involved, the Ukrainian authorities decided to organize a competition for the project, aiming at attracting the most original ideas and the most advanced solutions. 384 proposals were presented from Ukraine, Russia and from countries all over the world. They included impressive proposals from major engineering groups, as well as some modest contributions with highly imaginative concepts. 

It should be noticed that all the scenarios examined during the later studies, were already included in the so-called "KIEV competition" proposals. 

At the end of the selection process, six final candidates were selected by the Jury as those representing the best ideas and solutions for a second shelter. 

Following the competition, after having provided some technical assistance, the European Commission decided to fund a first feasibility study for the second shelter. In accordance with the European procedures, was organized a call for tenders in April 1994, by the DG1, in the framework of the TACIS Programme. 

The contract was awarded to the Consortium ALLIANCE, made up with CAMPENON BERNARD SGE (F), AEA Technology (GB), BOUYGUES (F), SGN (F), TAYWOOD (GB), WALTER BAU (FRG), with the support of the Ukrainian Academy of Sciences, ISTC Shelter, the Kurchatov Institute and the Ukrainian Association of Contractors. 

The ALLIANCE study remains the only comprehensive engineering study done on a solution for the Chernobyl Shelter number 2. The proposal made by ALLIANCE, after 16 months of datas gathering, conceptual studies and detailed engineering meets precisely the requirements expressed by the Ukrainian authorities: 

• stabilisation work sufficient to allow the construction of a new shelter
• construction of a new, independent shelter, capable to sustain the collapse of the remains of reactor 4 and/or of Shelter 1
• construction period of no longer than 5 years
• life of the new shelter above 100 years
• equipment and facilities for waste retrieval and management
• equipment and facilities for the future decommissioning of Unit 4. 

In September 95, after the issuing and approval of the final ALLIANCE report, the European Commission and the Ukrainian authorities decide to launch a new study aiming at optimizing the Shelter project, by reviewing the terms of reference (specifically the safety objectives and the corresponding design criteria) imposed to ALLIANCE and examining other possible approaches. 

This study ("Short Term and Long Term measures") was done by a team of experts, including experts from the ALLIANCE team, under the coordination of "Trischler und Partner" (FRG), specialized in geotechnics, pollution remediation and project management. After the start of the study, an agreement between the European Commission, the USA and Japan, allowed experts from these countries to join and to bring their contributions. 

The experts attended numerous workshops to review all the factors influencing the safety objectives and the design criteria, to examine various proposals made by suppliers and contractors and to establish consistent scenarios. Seven scenarios have been examined, after a preliminary sorting. Rough cost estimations were made, including the cost of managing the waste produced in each scenario. The study and the judgements of the experts did not allow to clearly favor one obvious "best" solution.

Finally, at the initiative of Trischler und Partner, was established a "Recommended Course of Actions", advocating for a set of Short Term measures, the preparation for conversion into an environmentally safe site and the Long Term conversion into an environmentally safe site. 

In fact, this "Recommended Course of Actions" is a juxtaposition of features included in the various options, of proposals made by the experts and of commercial proposals made by suppliers and contractors. It represents a stepwise approach to the Shelter problem, but it is not a comprehensive and demonstrated project, meeting precise short term and long term safety objectives. 

After approval "in principle" by the Ukrainian authorities and the G7 representatives, it was decided to deepen the "Recommended Course of Actions" approach and to prepare a Plan of Actions, allowing the financing and the launching of the most urgent actions. 

This work was done by a group of experts, approximately similar to the group involved in the previous study; given the very short delays allocated to the team (a few weeks), a huge work has been accomplished to review, detail, organize, plan and cost the various actions contemplated. 

The outcome of this work, the "Shelter Implementation Plan" ("SIP"), is a set of 22 tasks, adressing five major objectives: 

• reduce the short term potential for collapse of the Shelter (by structural stabilization)
• reduce the consequences of a possible Shelter collapse
• improve the nuclear safety of the Shelter
• improve the industrial safety of the Shelter
• develop a long term strategy for the conversion of the remains of reactor 4 to an environmentally safe site. 

The SIP takes into account the strategy for the stabilization of the "Shelter Object" condition, text recently approved by the Ukrainian authorities, which defines the official objectives of Ukraine, for the future of the remains of reactor 4. 

The SIP identifies a number of priority tasks, forming potential "early biddable packages". The outcomes of these packages are necessary to prepare further implementation of the SIP and could impose substantial modifications or reorientations of the SIP. 

The SIP proposal was endorsed by the Ukrainian authorities and by the G7 representatives and partial financing has been secured with the G7 nations, the Europeean Commission and Ukraine. 

The effective launching of this 750MUSD programme is foreseen for the first months of 1998. 

The SIP, with all the preceeding studies, has allowed considerable improvements on the knowledge and the understanding of the reactor 4 situation. It has allowed the training of numerous experts, the gathering of valuable data, the review of an important number of ideas and concepts. 

But the SIP suffers from congenital drawbacks, which should not be omitted during its implementation. 

The logic of the SIP is (with a simplistic formulation) that short-term stabilization measures will allow the construction of a safe confinement with reduced functional characteristics (compared with the criteria imposed to ALLIANCE), thanks to partial deconstruction and significative waste management (Fuel Containing Masses removal) during the period of effectiveness of the stabilisation (10 to 15 years). 

Three key factors are sustaining the logic: 

• the possibility to stabilize (that means to reduce the collapse probability to an "acceptable" level) for a 10/15 year duration, at a reasonable overall cost (monetary, doses, waste and jeopardy of future dismantling and waste management operations);
• the possibility to partially dismantle or deconstruct, using a light and "cheap" shelter;
• the feasibility of the "Fuel Containing Masses" and spent fuel particles removal and of the waste management operations, including the waste accumulated at the close vicinity of the shelter 1. 

The entire logic of the SIP is based on a satisfactory achievement of these three linked requirements and, in fact, the decision points on stabilization, waste management, safe confinement and deconstruction are tightly linked: this common decision point will be reached when the overall SIP Programme will be studied in detail, validated and fully demonstrated. Such a validation will obviously require iterations and trade-offs. 

The SIP is an addition of numerous tasks involving, for some of them, complex interventions in highly exposed areas; for most of these tasks, there exists no examples or references; the satisfactory completion of each individual task is mandatory to meet the overall requirements of the Programme (If only one minimum stabilization task is impossible, the overall Programme could be in jeopardy). 

It is then necessary to check and validate each individual task, with the following criteria: 

• the benefit brought to the overall SIP Programme
• its technical feasibility
• the dose uptake linked with the task and the measures to reduce the doses - its relationship with all the past, simultaneous and future tasks 
• the waste produced during its implementation and the associated measures. 

It is only when all the individual tasks have been checked and validated that the SIP will be considered as feasible. 

The objectives of overall dose minimization, cost reduction and overall consistency make mandatory a very tight coordination of all the interventions in the shelter: costs and doses uptake drifts will be mainly caused by redundant, useless or non efficient interventions. 

Once the individual tasks have been validated, it will be necessary to prepare each intervention, in close coordination with the operator; such an intervention will probably involve the operator of the Shelter, several trades, several contractors and supporting entities. It will require the use of the following functions: 

• access control
• utilities
• communications
• equipment and material handling - health physics - security
• waste management
• protection and shielding 

The preparation and the execution of these intervention schemes is a dominant factor for the organization of the on-site activities. It will require the close coordination of the designers of the concerned tasks, the contractors, the suppliers and the operator of "Ukritye", since the inception of the task. 

Intentionally, the SIP does not provide a comprehensive waste management Programme. But all the major activities of the SIP will produce waste: technological waste, contaminated waste, dust, rubbish, dismantling products, water, filters .... This waste can include graphite and spent fuel particles (from LL to VHL). 

The SIP should then be closely coordinated with the waste activities of the other multilateral or bilateral projects to insure that: 

• the treatment and storage facilities will exist;
• they will be suitable for the waste arising from the SIP activities;
• specific facilities will be built to treat and store the HL and LL waste.

The specifications of this waste Programme will directly impact all the SIP activities. 

Given the huge quantities of nuclear waste involved (more than 1 million of cubic meters), the cost of the waste management is, by far, the dominant economical factor of the Chernobyl Programme: inadequate or incomplete solutions could have considerable consequences in the future. 

The situation of the site, the duration of the Programme and the importance and complexity of the various activities of the Chernobyl Programme make necessary the establishment of strong logistical functions, including: 

• Documentation management
• CAD, Information systems
• Telecommunications
• Laboratories
• Housing, transportation
• Liaison with the local and national administrations (customs, tax, national agencies..)
• Information center for visitors, public, local industrialists, nuclear industry and donators 

It is obvious that this logistical support should be shared with all the on-going assistance projects on the site. 

For the first time in the history of the nuclear industry, a large and complex nuclear Programme will be implemented with the financial and technical support of the International Community. This Programme presents important risks and the likelihood of an accident is not theoretical. The Programme is done in a country with limited financial capabilities, which has not yet been able to accumulate the insurance reserves needed to face a serious nuclear accident. The Programme concerns an accidented nuclear facility with many unknowns and uncertainties. 

Before the effective launching of the Programme on site, it is absolutely necessary that the various interested parties establish a consistent and lasting liability and insurance regime, applicable for the Programme, without any loophole. 

It would not be acceptable that the final risks of an accident on the site rest practically on the suppliers, the contractors, the consultants and their staff. 

The Chernobyl remediation Programme is, potentially, a chance for the Ukrainian industry to develop specific and useful capabilities in the domains of nuclear site remediation, nuclear waste management and nuclear facilities dismantling. 

As it is done in all the large nuclear Programmes in the world, special attention should be given to the access of local firms to the various contracts: the creation of a dedicated local economical development agency is probably a good way to support such a national industrial policy. 

With the launching of the projects financed through the TACIS Programme, the NSA fund and the SIP fund, the Chernobyl remediation Programme is entering into a very active phase. The urgency of some of the decided actions, the willingness of the donating nations and of the operators to see an immediate start of the main projects and the wish of the Ukrainian authorities to see the financial effort of the Ukrainian nation to be complemented by international assistance should not hide the actual status of the Programme: 

• The initial studies made to identify and specify the projects are very limited in scope and in depth; they represent only a fraction (one tenth approximately) of what is considered as a minimum for the launching of a typical nuclear project. 
• The specific nature of the Chernobyl remediation Programme does not require a compulsory call to non-conventional project organizations; basic project management rules apply and the strict application of these rules will probably be beneficial for the success of the Programme. Priority should be given to the establishment of all the necessary and lasting structures of the Programme (PMU, Engineering, experts Groups...). 
• In the long range, the Chernobyl remediation Programme will be handled by the Ukrainian authorities, using Ukrainian funds, with the support of the Ukrainian industry; a clear "industrial policy" will help the progressive development of the necessary autonomous capabilities. 
• The liability issue and the attached insurance coverage scheme should be in place, without any miss.