1. International Conference on the Safety of Radioactive Waste Management
Post-Accident Waste Management in Ukraine: Challenges and Steps Needed to Resolve the Accident Waste Problem
T. Kilochytska, State Nuclear Regulatory Inspectorate of Ukraine L. Zinkevich, State Agency of Ukraine on Exclusion Zone Management
I. Shybetskyi, Radioenvironmental Centre of National Academy of Sciences of Ukraine
J. Krone, DBE TECHNOLOGY GmbH, Peine, Germany
International Conference on the Safety of Radioactive Waste Management
21-25 November, 2016, Vienna, Austria
16May JC 2nd Review Meeting, Presentation of Ukraine

2. Content History of accident waste in Ukraine
The main places of localization
Volumes, activity, characteristics
Challenges of accident waste management
Steps to resolve the problem of accident waste
Lessons learnt
Conclusions

3. The 26th of April, 1986: Accident at Chernobyl NPP Unit 4
accident of the 7th level of the INES
1,3 · 1019 Bq of activity released
˃ 145,000 km2 of contaminated area
totally destroyed:
reactor core
safety related systems
high levels of exposure doses - fragments of nuclear fuel and graphite around the destroyed unit, hot particles on landscapes
elimination of accident subsequences:
Decontamination of ChNPP site, landscapes and roads
Collection of radioactive waste, construction of RAW storages and repositories
Covering of ChNPP site with concrete
The accident at the Unit N 4 of Chernobyl NPP happened the 26th of the April At that time it was the most serious accident in the history of nuclear energy use.
Nuclear facility was totally destroyed, all protective barriers were damaged. 145,000 km2 were contaminated – mostly, the territories of Ukraine, Belarus, Russian Federation.
Sweden, Germany, Norway, Poland, Finland, Austria, Switzerland and other European countries also was impacted (influenced).
It happened in Soviet Union time and it was decided to create high level Governmental Commission to manage the situation and plan and implement all measures related liquidation of subsequences.
During the first weeks after the accident people in Ukraine did not receive true and adequate information about this accident.
One of the decisions of Governmental Commission was to eliminate the subsequences as fast as possible and start normal work at Chernobyl NPP Units 1,2,3.
Liquidation of accident subsequences: decontamination of ChNPP site, surround (residential) areas and roads:
to decrease the exposure doses and allow workers (“liquidators”) to mitigate accident subsequences
to provide activity at the Units N 1,2,3
to allow people re-evacuation (this purpose wasn't reached)
To reach this goal a lot of decontamination works were reformed. In parallel scientific and research institutes started developing the design of protective facility – current “Shelter Object” .

4. November, 1986: Construction of ChNPP’s Shelter Object
Definition (1): a part of the ChNPP industrial site and complex of facilities, including:
damaged structures and systems of ChNPP unit 4, which loose all designed functions,
and
new structures and systems, that serve to mitigation of radiological consequences
Definition (2): a “place for temporary surface storage of unorganized radioactive waste”
The special License:
requires to keep the Shelter Object in safe conditions
and
allows to do the steps for “its transformation into ecologically safe system”
You ca see two photos – one with process of creation of protective walls and constructions as a part of existing Shelter, and second photo – is Shelter Object.
In our National Strategy we can find a number of Shelter Object definitions and description (some of them is on the slide).
In the same time “uniqueness” of this facility was a great challenge for Operator (Chernobyl NPP) and Regulatory Body.
How to regulate the Shelter Object? What type of License should be issued? How to apply existing safety requirements developed for normal nuclear units or radioactive waste management facilities?
To answer this questions the Regulatory Body changed the “formal” approach and tried to find more effective mechanism of work with the Operator (a number of working groups were organized to solve questions of “regulating” of Shelter Object)

5. National Strategy for Transformation of Shelter Object into Ecologically Safe System
Stage 1: Stabilization of the existing facility, improvement of operational reliability of structures and systems (finished in 2008)
Stage 2: Construction of New Safe Confinement for providing the necessary conditions for Stage 3 activities:
safety of workers, public and environment,
development of technologies for FCM removal
creation of for RAW Management infrastructure
(under finalization)
Stage 3: Retrieval of FCM and LL RAW:
Removal
Conditioning
Disposal
and
Shelter Object decommissioning
(in the future)
The National Strategy for Shelter object transformation into an environmentally safe system was approved in 2001.
This Strategy includes three main stages for destroyed Unit N 4: In accordance with the "Strategy" Shelter object transformation into ecologically safe system is achieved through implementation of three main stages
The first stage – Shelter object stabilization and collapse risk reduction to the acceptable level.
The second stage - creation of additional protective barriers and conditions for further transformation of the Shelter – New Safe Confinement
The third stage - FCM materials and Radioactive Waste retrieval from the Shelter and their conditioning.
I would like to focus your attention on the Ukrainian terminology. For works at the Shelter object it was accepted the term - Shelter object transformation into environmentally safe system. Even today we don’t use the term decommissioning to the works at Shelter object. Decommissioning will be used (may be) after complete retrieval of FCM.
It is important to add that Ukraine is supported by the international community during the implementation of activity of transformation of Shelter Object into ecologically safe system

6. Accident waste ~ “Chernobyl Waste”
Shelter Object waste
Fragments of destroyed Unit 4
Contaminated soil
Wood (e.g., “The Red Forest”)
Fragments of civil engineering structures, debris
Contaminated equipment
Fragments of metal structures, concrete and various debris
Miscellaneous

7. “Chernobyl Waste”: localization
Mostly within Chernobyl Exclusion Zone:
Shelter Object (on ChNPP site)
Radioactive waste disposal sites (RWDS): “Buriakivka”, “Pidlisny”, “3rd Line of ChNPP”
Numerous radioactive waste temporary localization sites (RWTLS)
Storage and disposal facilities of the “Vector Complex” (for future storage and disposal)

8. “Chernobyl Waste”: inventory and characteristics
96% of all radioactive waste amount in Ukraine
total amount estimated at million m3 (including million m3 have been already disposed at RWDS“Buriakivka”)
very different in they radionuclide composition and specific activity
contain long-lived radionuclides (α- emitting nuclides U, Pu, Am … in concentrations that are not acceptable for near surface disposal)
“stored” or ”disposed” (RWDS and RWTLS) in conditions which do not comply with safety requirements (except of RWDS“Buriakivka”)
required safety assessment and “re- disposal”

9. Waste of Shelter Object
Volume … m3
Total activity 4,1‧1017 Bq
Volume of long lived RAW m3
fragments of building structures,
reactor core materials thrown inside during the accident
fuel (app. 200 tons), irradiated graphite,
fuel containing materials (FCM)
radioactive dust and
liquid RAW
The most problematic and dangerous radioactive materials in Shelter Object is Fuel Containing Materials
The major amount of fuel is in the form of Fuel Containing Materials - FCM.
The percentage of uranium in the bulk of FCM ranges from 5 to 10%. The total amount of FCM is estimated as 500 m3.
 In addition to the nuclear hazard of FCM there is a risk of formation (generation) of fuel dust because of destruction processes during the 30 years after the accident.
Dust is generated on the surface of the irradiated fuel and can release outside the Shelter. To solve the problem of “fuel dust” the special “Dust Suppression System” was installed inside the Shelter Object.
Of course, according to the National Strategy of Shelter Object Transformation, RAW and fuel materials should be retrieved and allocated in safe and controlled conditions.

10. National Policy and Strategy
Radioactive Waste Management Strategy in Ukraine (approved by the Order of Government № 990, 19 August 2009)
National Program of Radioactive Waste Management (approved by Low of Ukraine № 516-VI, 17 Sept 2008)
National RAW Management Fond

11. Challenges of accident waste management (1): RAW classification
Current classification defines two types of RAW depending on disposal method:
1st type: RAW to be disposed in Near-surface disposal facility (low- and intermediate level short-lived RAW)
and
2nd type: RAW to be disposed in Geological disposal facility (high-level RAW, long-lived RAW – Shelter’s FCM)
Current classification:
does not support a cost-effective waste disposal (large amount of “Chernobyl waste” requires a geological disposal due to high content of α-emitting nuclides)
does not define “Chernobyl waste” as a separate class

12. Challenges of accident waste management (2): safety requirements
Presence of long-lived radionuclides constitutes the main problem with near-surface disposal of “Chernobyl waste”
IAEA and Ukrainian safety requirements for near-surface disposal:
IAEA, GSG-1: RAW with a specific activity of long-lived alpha emitting nuclides of up to 400 Bq/g on can be disposed in near-surface facilities; Ukraine: a limit of 0.1 Bq/g is often applied
IAEA, SSR 5: a dose constraint for the future exposure by a disposal facility should not exceed of 0.3 mSv a year; Ukraine: this limit is 0.01 mSv a year
Ukraine: very "strict" intrusion scenarios are used for safety assessments of the disposal facility (e.g., the direct consumption of water from a well drilled into the waste pile at the end of the institutional control period)
Due to strict national safety requirements, the majority of accident waste would require geological disposal. It would be practically impossible due to economic considerations

13. Challenges of accident waste management (3): retrieval of RAW&FCM from Shelter
Dismantling of “old” Shelter (perspectives and capabilities)
Fuel and FCM monitoring and investigations
Developments of FCM&RAW retrieval technologies, taking into account:
High exposure doses
Access difficulties
What will be “the end-state” of Shelter transformation ?
CHALLENGE 3: Criteria to be achieved after finalization of all activities related “transformation of Shelter Object into ecologically safe system”
I mentioned few times that activity related to the Shelter Object is “transformation into ecologically safe system”.
We know that normal planning of decommissioning requires the establishing of qualitative and quantitate criteria to characterize the “final state” of facility and its site after of works related decommissioning.
For totally destroyed nuclear facility (as Shelter Object) we can not establish clear criteria for “ecologically safe system” because of uncertainties related fuel materials removal.
In such case, we use so called intermediate criteria based on the approved designs (for example, stabilization, confinement) according to the approved Strategy.
From time to time we have discussions that we should review and update our National Shelter Object Transformation Strategy am clarify as much as possible our expectations to be achieved in the end.
May be we should predict few options taking into account our concerns regarding removal of all waste and fuel from the Shelter.
???

14. Steps to resolve the problem of accident waste management (1)
Implementation of new waste classification scheme
First type: landfill repository for VLLW, Sweden
(In Ukraine Buriakivka)
Second type: surface repository for LLW, France (in Ukraine – Vector)
Fourth type: DGR (KBS-3V, Sweden) for co-disposal of ILW and HLW
Fourth type: DGR (VDH, Sweden) for disposal of HLW
Third type: GR at intermediate depth for disposal of ILW (SFR, Sweden)
Class
Description
Disposal option
Very Low Level Waste (VLLW)
not determined in Ukraine - large volumes of waste in Ukraine can be classified as VLLW
Landfill repositories (first type)
Low Level Waste (LLW)
corresponds to existing short-lived waste
Surface repositories (second type)
Intermed. Level Waste (ILW)
corresponds to existing long-lived waste
Repository at interim depth (third type)
High Level Waste (HLW)
corresponds to existing heat-generating HLW
Deep geological repository (fourth type)
The new classification system provide significant savings in waste management by cost effectively allocating waste to the most optimal repository solution for each waste class
[Project U4.01/08-C, 2012]

15. Steps to resolve the problem of accident waste management (2)
Updating of National Safety Standards
It is necessary to eliminate excessive conservatism in some of the Ukrainian requirements for RAW disposal and to bring them into line with international best practices (SSR-5, GSR Part 5)
Improvement of Waste Characterization
To best benefit from the new classification system improvements in sorting and characterization processes are needed.
Improved characterization and sorting of RAW will require appropriate planning taking into account:
the specific characteristics of the accident waste
appropriate waste acceptance criteria for disposal

16. Steps to resolve the problem of accident waste management (3)
Specific WAC for “Chernobyl waste”
Special, less restrictive Waste Acceptance Criteria (WAC) for VLLW and LLW accident waste disposal facilities within the ChEZ, could be established based on safety assessments that take credit for the special restrictions
These WAC can be derived from estimates of potential radiation exposure to critical groups living completely outside of the ChEZ and would be applicable only to accident waste
According to the Draft of Strategy for future development of Chernobyl Exclusion Zone:
10 km zone (a special industrial zone) will never be populated
Other territories will serve as “buffer zone”
In particular these restrictions include the requirement to limit public access to the entire area encompassed by the ChEZ and to restricted land use over long timeframes because of the overall level of contamination within the zone. These WAC can be derived from estimates of potential radiation exposure to critical groups living completely outside of the ChEZ and would be applicable only to accident waste. However, after the end of an assumed institutional period that can be assured for only a few hundred years, the potential exposure to any individual even inside the ChEZ should not exceed under any circumstances the intervention limit of 1 mSv per year.

17. Lessons learned (1): management of accident waste
Strategical view is needed:
Is existing system of RAW management appropriate to solve the problem of accident waste (predisposal and disposal)?
Is existing “concept of RAW disposability” appropriate to solve the problem of accident waste?
If not: “What” should be revised and updated (classification, safety requirements for RAW disposal, characterization methods, financial assurance)?
Special WAC for disposal in surface repositories
Status and restrictions of special zone should be approved on the Governmental level
“Safety case” for near-surface disposal of accident waste needs to be discussed involving interested parties
Additional (specific) safety requirements should be established

18. Lessons learned (2): activities on Shelter Object Transformation
Since 1998 the implementation of large project “Shelter Implementation Plan” has been supported by international community
New Safe Confinement (“Arch” project) costs 1,5 billions Euros. Dismantling and removal of RAW&FCM require much more funding
After 30 years after the accident:
RAW&FCM still should be characterized
dismantling of Shelter’s structures and retrieval of RAW&FCM require the additional RAW management infrastructure
development of technologies for RAW&FCM retrieval requires R&D support
involvement of international experience is needed
Revision of National Strategy (2001) for Shelter Object is needed

19. Conclusions
Solving the problem of management of “Chernobyl waste” requires:
a systematic review of the existing norms and regulations with respect to best international practice of radioactive waste management
improvement of the existing classification / characterization of radioactive waste with a focus on disposal
improvement of the safety assessment approaches for licensing the disposal of accident waste, taking into account relevant safety features and site specific conditions
involving of international experience and support to plan and perform safety related activity on the Shelter Object transformation

20. Thank you for your attention!