Miljövänner för kärnkraft i Östhammar

Transcription

1 Miljövänner för kärnkraft i Östhammar 23 oktober 2002 Förvar av använt kärnbränsle och avfall Ett internationell översikt Frigyes Reisch

2 Förvar av använt kärnbränsle och avfall Våtförråd - CLAB Torrföråd - US NRC - Idaho, USA - Tjernobyl 1,2,3 - Sarkofag Slutförvar TMI 2 Biologi - Äspö - SFR - Olkiluoto, Finland - Yucca Mountain, USA - Konrad Mine, Tyskland International Electrotechnical Commission

3 CLAB

4 Dry Storage NRC DOE National Nuclear Fuel Program, USA

5 NRC Dry Storage Cask and Cannister

6 The Idaho Chemical Processing Plant's Irradiated Fuel Storage Facility is an example of an air-cooled, vault-type dry storage facility for spent nuclear fuel. After spent nuclear fuel is removed from the reactor, it is placed inside concrete basins of water within the reactor facility. The water cools the spent nuclear fuel and shields workers from radiation. The "wet" method of storing spent nuclear fuel is not intended to be permanent. As the basins reach their storage capacity, some of the spent fuel must be moved to make room for future spent fuel when it is removed from the reactor. Spent nuclear fuel that has been cooled may be moved to a "dry" storage area. Using remotely handled equipment, the spent fuel is removed from the pool, dried, and placed in specially designed canisters. The canisters are either stored in a shielded container or in a shielded vault-type dry storage facility where the circulation of air provides cooling. Dry storage reduces corrosion concerns associated with extended storage of fuel under water, provides all the safety characteristics of wet storage, and is less expensive to operate. The Idaho Chemical Processing Plant's Irradiated Fuel Storage Facility is an example of an air-cooled, vault-type dry storage facility for spent nuclear fuel.

7 Chernobyl 1,2,3 Dry Storage 1. The RBMK fuel assembly with a length of ~10m is cut into three pieces: 2 fuel bundles and 1 extension rod. 2. Due to the leakage of approximately 10 percent of the fuel rods and in order to avoid regular and systematic inspection of each fuel assembly it has been decided to place each assembly in a cartridge, which will be filled with helium and sealed, providing the 1 st barrier. 3. The 196 cartridges will then be placed in a storage cask, which will also be filled with helium and sealed and which serves as 2 nd barrier. 4. The storage cask will be transported to the storage module inside a transfer cask on a railway type transfer trailer. The storage cask will be housed in the concrete storage modules serving as radiological protection for the population and protection of the storage cask against external hazards and providing natural circulation for cooling of the storage casks. The outlet temperature will be controlled and the radiological conditions of the environment will be monitored Modules

8 13 december 2000 Tjernobyl stängs för gott Problem med sprickor och radioaktivt avfall återstår att lösa Drygt 14 år efter katastrofen i Tjernobyl stängs nu det omdiskuterade kärnkraftverket för gott. Den sista reaktorn tas ur drift den 15 december och världen över drar många en lättnadens suck. Men det är inte slut på problemen. Den i hast byggda sarkofagen kring olycksreaktorn läcker och hotar att störta samman..... Den svenska kärnkraftexperten Frigyes Reisch varnar för att bara bygga en ny sarkofag runt den gamla utan att ventilera ordentligt: - Det går inte bara att fylla på mer betong. Det finns en hel del restvärme kvar. Om värmen stängs inne så kan det förvärra situationen genom att nya sprickor bildas. Sarkofag

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10 Repository Äspö SFR Finland Yucca Mountain, USA Konrad Mine, Germany (f.d. järngruva) Low and medium level waste

11 Äspö SKB

12 SFR

13 Finland, Olkiluoto

14 President Signs Yucca Mountain Bill July 23, 2002

15 Pressemitteilung BfS gets licence for Konrad mine Amount of waste cut in half Today the licence (plan-approval decision) for the planned Konrad repository was given to the Federal Office for Radiation Protection (BfS) by the Lower Saxonian Environmental Ministry. The federal state authority is the competent licensing authority. The application was filed twenty years ago by the Federal Institute of Physics and Metrology (PTB) in Braunschweig being responsible at that time.

16 U.S. Nuclear Regulatory Commission The Accident at Three Mile Island Current Status Today, the TMI-2 reactor is permanently shut down and defueled, with the reactor coolant system drained, the radioactive water decontaminated and evaporated, radioactive waste shipped off-site to an appropropriate disposal site, reactor fuel and core debris shipped off-site to a Department of Energy facility, and the remainder of the site being monitored. The owner, General Public Utilities Nuclear Corporation, says it will keep the facility in long-term, monitored storage until the operating license for the TMI-1 plant expires in 2014, at which time both plants will be decommissioned. Below is a chronology of highlights of the TMI-2 cleanup from 1980 through Date Event July 1980 Approximately 43,000 curies of krypton were vented from the reactor building. July 1980 The first manned entry into the reactor building took place. An Advisory Panel for the Decontamination of TMI-2, composed of citizens, Nov scientists, and State and local officials, held its first meeting in Harrisburg, PA. July 1984 The reactor vessel head (top) was removed. Oct July 1986 Aug Jan July 1990 Jan April 1991 Feb Aug Sept Sept Dec Defueling began. The off-site shipment of reactor core debris began. GPU submitted a request for a proposal to amend the TMI-2 license to a "possession-only" license and to allow the facility to enter long-term monitoring storage. Defueling was completed. GPU submitted its funding plan for placing $229 million in escrow for radiological decommissioning of the plant. The evaporation of accident-generated water began. NRC published a notice of opportunity for a hearing on GPU's request for a license amendment. NRC issued a safety evaluation report and granted the license amendment. The processing of accident-generated water was completed involving 2.23 million gallons. NRC issued a possession-only license. The Advisory Panel for Decontamination of TMI-2 held its last meeting. Post-Defueling Monitoring Storage began.

17 Biology Superbug Survives Radiation, Eats Waste A can of spoiled meat and nuclear waste may appear to have little in common, but the microbe Deinococcus radiodurans finds both environments rather cozy. Scientists hope this organism's ability to withstand massive doses of radiation will make it a useful tool for toxicsite remediation

18 Foreword Introduction International Electrotechnical Commission Working Group 5/45A: Special Process Measurements Project IEC (Technical Report), Instrument and Control Systems (I&C) of interim storage and final repository of nuclear fuel and waste 1 Scope 2 Normative references 3 Terms and definitions 4 General principles 5 Structure 5.1 Storage at fuel fabrication plants Table of contents 5.2 Storage at nuclear power plants Wet storage of spent nuclear fuel Dry storage of spent nuclear fuel Storage of radioactive operational and decommissioning waste 5.3 Storage at interim storage facilities Wet storage of spent nuclear fuel Dry storage of spent nuclear fuel Storage of radioactive operational and decommissioning waste 5.4 Storage at reprocessing facilities Wet storage of spent nuclear fuel Dry storage of spent nuclear fuel Storage of reprocessed material Storage of radioactive operational waste 5.5 Final repositories for radioactive operational and decommissioning waste 5.6 Packaging 5.7 Retrievable repositories for spent nuclear fuel Deep repositories 5.8 Transportation Sea carriage of spent nuclear fuel Land carriage of spent nuclear fuel Sea carriage of radioactive operational waste Land carriage of radioactive operational waste