Historical Background of the Operation, Closure and Monitoring of Andra s CSM Disposal Facility

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1 Historical Background of the Operation, Closure and Monitoring of Andra s CSM Disposal Facility Jean-Pierre VERVIALLE Director, Andra s Centre de Stockage de la Manche IAEA-Andra International Workshop, Cherbourg,

2 CONTENTS Historical background Waste acceptance at CSM Description of the CSM disposal facility Licensing context of the closure & monitoring phase Preserving the memory Conclusions 2

3 Historical background 3

4 A NEW APPROACH TO WASTE DISPOSITION In the early 1960s, most nuclearised countries were dumping their radioactive waste into the sea Then a new approach was progressively implemented Concentrate & Confine instead of dilute and disperse Decision to create the CSM in the late 1960s Order of 19 June 1969 : transfer of operation from French Atomic Commission (CEA) to INFRATOME Start-up of operation in October

5 LOCATION OF THE CSM FACILITY Cherbourg The Centre de la Manche Disposal Facility (CSM) is located 20 km west of Cherbourg, close to AREVA NC facility of La Hague. Publication of Decree No of 10 January 2003 CSM enters into its new monitoring phase and, by Order, to pursue the release of effluents. 5

6 FROM CREATION TO POST-CLOSURE MONITORING Milestones in the evolution of the facility and time schedule First French surface disposal facility for low- and intermediate-level radioactive waste Total area : 14 ha Disposal area : 12 ha 527,225 m 3 920,000 containers Earth trench Concrete trench & platforms Storage in tumulus et monolith Multi-barrier concept Experimental phase Transition phase Industrial phase Monitoring phase 1969 Decree creating the facility 1967 Site selection Tritium Incident Change in disposal concept 1979 Foundation of Andra (CEA) Law of 30 Dec Last canister Installation of the cover 2003 Monitoring phase

7 Waste acceptance at CSM 7

8 WASTE ACCEPTANCE CRITERIA (1/2) Which type of waste is found at the CSM? Evolution of Waste Acceptance Criteria From June 1969 and 1984, WAC have been prescribed by CEA for INFRATOME, in accordance with the CSM s creation decree Waste concerned is defined as low-level waste if the maximum permitted concentration in drinking water or MPC is less than 1,000 MPC ( Ci/m 3 for 239 Pu) for contained waste. No mention about the radioactive half-life of the RN. It means that some long-lived RN, such as Pu, Th, U and Ra, have been allowed to be disposed of at the CSM. Waste contained in drums and products in bulk had to be disposed of in concrete cells before being grouted with concrete. 8

9 WASTE ACCEPTANCE CRITERIA (2/2) Evolution of Waste Acceptance Criteria From 1985 to 1994: in 1985, Basic Safety Rule RFS I.2 prescribed that : the average in emitters of the entire facility shall not exceed 0.01 Ci /t (370 MBq/t) at the end of the institutional control period, the maximum specific activity in under 0.1 Ci/t (3.7 GBq /t) emitters of each waste package shall remain october 1986 : as a complement, Basic Safety Rules RFS III.2.e imposed systematic waste packaging and established minimal constraints in containment characteristics, on 30 June 1994, after 25 years of operation, CSM received its last waste package. 9

10 WASTE INVENTORY Waste inventory : Volumes and activity : Volume : 527,225 m 3 Total activity alpha emitters in 300 years : 526 TBq Total activity beta-gamma emitters in 300 years : 974 TBq Nickel : 21 tonnes Cadmium : 15,3 tonnes Chemical toxicity : 10

11 Description of the CSM disposal facility 11

12 DISPOSAL STRUCTURES Different operating concepts 1971 : above ground platform 1969 : trenches 1969 : concrete trenches 1985 : in monolithic cells 1988: above ground disposal structure 1994: disposal of last drum september September 2009

13 WATER MANAGEMENT SYSTEM Before 1976, surface waters (rain having possibly been in contact (or not) with packages) were released in the St. Helen s River, after control Following the 1976 event where tritium was released into the environment, the water management system was upgraded, in particular thanks to the construction of a separative water collection network initiated in An underground monitoring gallery was built and a drainage pipeline system was installed to collect seepage water effluents from the disposal platforms. 13

14 CAPPING SYSTEM Between 1991 and 1997, the final capping system was constructed over the disposal area. Its imperviousness results from a multilayer structure integrating local materials (sandstone, schists, sand) and a bituminous membrane September 2009

15 Licensing context of the closure & monitoring phase 15

16 TRANSITION TO THE MONITORING PHASE Licensing process: All together a nine- year process 2 October to 30 November 1995, first public inquiry concluded to a favourable opinion to enter into the monitoring phase, 2 February 1996: establishment of an independent commission (TURPIN S Commission) to provide an experts assessment on the environmental impact of the facility, 19 December 1996: conclusions / recommendations of the TURPIN s Commission endorsed by the government September 2009

17 TRANSITION TO THE MONITORING PHASE Conclusions / Recommendations from TURPIN s commission: The monitoring phase should be divided into three steps: a first five-year period requiring a very active monitoring of the facility, a second period involving an active monitoring, a third period consisting in very limited monitoring Provided that relevant measures be taken, the disposal facility does not pose any significant health risk for local populations; furthermore, the cover provides an essential feature to the safety of the facility. Radioactivity is not distributed equally throughout the facility, particularly with regard to activity; a significant amount of lead (and toxic chemicals) has been detected within the facility. The facility should not be totally forgotten after 300 years, and it is imperative to preserve the memory of the site September 2009

18 TRANSITION TO THE MONITORING PHASE Upon the Commission s proposal, a specific monitoring committee (CSCSM) was created on 18 December Between February and May 2000, two joint public inquiries were held. In June 2000, the Commission issued favourable opinions concerning Andra s demands, accompanied by some reservations and recommendations. After a 2.5-year review, two documents were issued on 10 January 2003 : Decree No authorising the transition into its monitoring phase, and the Order authorising the facility to release gas and liquid effluents resulting from its operation. 18

19 Preserving the memory 19

20 PRESERVING THE MEMORY Preserving the memory on site Documentation of the facility duplicated on a long-term paper Copy of all the records kept at the French National Archives, near Paris. A summary of it was also prepared for local administrations and communes. 20

21 CONCLUSIONS CURRENT SITUATION & EVOLUTION Very low impact of CSM on its environment (will be detailed by B.Cahen) Performance of the capping system: Subsidence areas on the capping system? Slight movements on slopes Report on a more sustainable capping system submitted to the Nuclear Safety Authority (ASN). Review by ASN in progress. Closely monitoring tritium in groundwater Preserving the memory September 2009

22 Thank you for your attention 22