A FEDARAL COMPANY IN GERMANY Uranium Mining and Milling Environmental Liabilities Manage- ment in Germany – Lessons Learned During Almost two Decades of Implementation of the WISMUT Rehabilitation Project P. Schmidt, S. Mann, M. Paul, Wismut GmbH Chemnitz, Germany Presentation at URAM2009, IAEA, Vienna, June 22 – 26, 2009 WISMUT Rehabilitation Project - Historical background
1946 The Soviet occupation forces in Germany established the state-run company SAG WISMUT with the sole aim to exploit the East German uranium deposits for the Soviet nuclear program. 1954 Foundation of the bi-national Soviet-German company SDAG WISMUT, continuation of the uranium production with a workforce of up to 120‘000 employees. until 1990 WISMUT produced 231’000 tonnes of uranium and had been the world’s third largest producer until that time
1990 Following re-unification of Germany, the uranium production was terminated in particular for economic reasons. WISMUT GmbH, with the Federal Republic of Germany as sole shareholder was built. Its corporate purpose is to decommission the former uranium mining and milling facilities and to rehabilitate the sites.
1991 The WISMUT Environmental Rehabilitation Project was initiated, the German Federal Government earmarked a total of € 6,6 billion (later updated to € 6,4 billion) to fund the Project.
P. Schmidt et. al. : The WISMUT Rehabilitation Project: State of Implementation and Lessons Learned Presentation at URAM2009, IAEA, Vienna, June 22-26, 2009 2 Location of the WISMUT sites
T H Ü R I N G E N S A C H S E N Dr e sd e n G itte rse e Ronneburg Kön ig ste in
AB AB Crossen Seelingstädt
Aue
Pöhla
P. Schmidt et. al. : The WISMUT Rehabilitation Project: State of Implementation and Lessons Learned Presentation at URAM2009, IAEA, Vienna, June 22-26, 2009 3 Production phase 1946 – 1990
3 5 mines, 1 open pit , 3700 ha operational areas 64 mine dumps,311 Mio. m waste rocks
3 2 processing plants, of 140 ha area Tailings ponds, 570 ha, 178 Mio. m
P. Schmidt et. al. : The WISMUT Rehabilitation Project: State of Implementation and Lessons Learned Presentation at URAM2009, IAEA, Vienna, June 22-26, 2009 4 Classes of objects - object-specific remediation technologies Contaminated Demolition, decontamination, clean-up of areas, structures and areas Release of lowly contaminated material for restric- ted reuse, safe disposal of higher contaminated material
Waste rock dumps In-situ remediation (re-shaping, slope stabilisation, covering); alternatively relocation to a safe site
Tailings management Dry In-situ remediation (dewatering, geo-technical facilities (TMF) stabilisation, cover placement)
Lichtenberg open pit Backfilling of waste rock material
Mines Closure of mine openings, stabilisation of under- ground mine galleries, controlled flooding
Contaminated water Active water treatment in special plants, alterna- (mine water, seepage, TMF tively passive water treatment procedures pore and supernatant water) (biological treatment technologies, phytoremediation, etc.)
P. Schmidt et. al. : The WISMUT Rehabilitation Project: State of Implementation and Lessons Learned Presentation at URAM2009, IAEA, Vienna, June 22-26, 2009 5 Demolition of structures and clean-up of areas
Situation in 1991 October 2008 Demolition of the Seelingstädt processing plant Release of not and lowly con- taminated material for re-use (here: for scrap smelting)
P. Schmidt et. al. : The WISMUT Rehabilitation Project: State of Implementation and Lessons Learned Presentation at URAM2009, IAEA, Vienna, June 22-26, 2009 6 In-situ remediation of waste rock dumps (dump #366, Schlema-Alberoda)
1994 1998
2000 2002 2008
P. Schmidt et. al. : The WISMUT Rehabilitation Project: State of Implementation and Lessons Learned Presentation at URAM2009, IAEA, Vienna, June 22-26, 2009 7 Dry In-situ remediation of Tailings Management Facilities
Technology (a) Removal of the „free” pond water and pore water; (b) Placement of an interim cover on the tailings surface to provide the consolidation load and create a stable working platform; (c) Construction of a stable surface contour providing suitable run off conditions for the surface water; (d) Capping of surface with a final cover P. Schmidt et. al. : The WISMUT Rehabilitation Project: State of Implementation and Lessons Learned Presentation at URAM2009, IAEA, Vienna, June 22-26, 2009 8 Backfilling of the Lichtenberg open pit
27.2 Mio m³ dump Nordhalde 1998 - 2003 7.9 Mio m³ 7.5 Mio m³ Paitzdorf dump dump 2005 - 2007 Gessenhalde 1991 - 1995 Open pit Lichtenberg
65 Mio m³ dump Absetzer- 6.3 Millionen m³ halde 1993 - 2005 Reust dump 20052007
1991 May 2008
• Operation: 1958 – 1977 • Dimension: Area 160 ha, Length 2 km, Width 1 km • Volume: 160 Mio. m³
P. Schmidt et. al. : The WISMUT Rehabilitation Project: State of Implementation and Lessons Learned Presentation at URAM2009, IAEA, Vienna, June 22-26, 2009 9 Controlled flooding of the Königstein mine
S N
ground shaft water water treatment 3rd aquifer fault Elbe River Königstein 140 m a.s.l. mine flooding water aquitard
4th aquifer geolog.Basement control drift
P. Schmidt et. al. : The WISMUT Rehabilitation Project: State of Implementation and Lessons Learned Presentation at URAM2009, IAEA, Vienna, June 22-26, 2009 10 Treatment of contaminated water
from sophisticated water treatment plants to passive water treatment facilities
WTP Königstein
wetland Pöhla
P. Schmidt et. al. : The WISMUT Rehabilitation Project: State of Implementation and Lessons Learned Presentation at URAM2009, IAEA, Vienna, June 22-26, 2009 11 State of Rehabilitation – March 2009
Underground remedation
Abandonment of mine workings 99%
Backfilling of mine voids 99%
Mine flooding 93%
Safeguarding underground workings 93%
Above ground
Demolition of structures 90%
Contouring/Profiling 90%
Covering of surfaces 65%
Reclamation areas 61%
Water Treatment 50%
P. Schmidt et. al. : The WISMUT Rehabilitation Project: State of Implementation and Lessons Learned Presentation at URAM2009, IAEA, Vienna, June 22-26, 2009 12 Funding (by the Federal Government, Ministry of Economics and Technology)
Wismut aggregate €6.4 bn. Funding of remediation in the (exclusively committed by the Federation) Free State of Saxony €3.0 bn. 0.6
1.3 2.4
5.1 Funding of remediation in the Free State of Thuringia
0.7 €3.4 bn. Accrued costs by 2008
2009 to completion 2.7
P. Schmidt et. al. : The WISMUT Rehabilitation Project: State of Implementation and Lessons Learned Presentation at URAM2009, IAEA, Vienna, June 22-26, 2009 13 Lessons learned during almost two decades of implementation of the WISMUT Project
I Cost driving factors I Clear definition of remediation criteria I Proof of remediation success I Model predictions I New challenges I Stakeholder involvement and regaining public trust
P. Schmidt et. al. : The WISMUT Rehabilitation Project: State of Implementation and Lessons Learned Presentation at URAM2009, IAEA, Vienna, June 22-26, 2009 14 Lessons learned: The eight cost drivers of the WISMUT projecting factors (1)
Decommissioning / rehabilitation costs: 38 US $ per kilogram uranium produced I Low grades (~ 0.1 % U): U / tailings = 825; U / total mine waste = 5,585 I Sulfidic & polymetallic nature of deposits: acid rock drainage, broad spectrum of contaminants of concern I Humid climate (covers, water treatment) I Radiological impact in a densely populated area I Lack of sustainability of former mining No parallel remediation, no prevention Acid UG Leach Mining in a sensitive area I Unplanned stop of production with no closure strategy Sub-optimal legacy situations to start with (e.g. TMFs) No permits available, substantial standby costs ! I New, stricter regulations superimposed to an „old“ system I Social cost included: Staff reduction from 45,000 employees (1991) to 1,700 (2008)
P. Schmidt et. al. : The WISMUT Rehabilitation Project: State of Implementation and Lessons Learned Presentation at URAM2009, IAEA, Vienna, June 22-26, 2009 15 Lessons learned: The eight cost drivers of the WISMUT projecting factors (2) ... and what we can learn from: I Plan with the closure in mind from day one. I Invest in Prevention to prevent long term liabilities. I Start early with partial rehab work. I Concerning the closure plan: See your site as a whole (conceptual site model) Take care of uncertainties in data & knowledge Beware of extreme events (e.g. floods) prefer „nature-close“ remedial options instead of sophisticated engineered facilities (also with respect to long-term cost minimization ) I Realize early involvement of all relevant stakeholders as key to acceptance !
P. Schmidt et. al. : The WISMUT Rehabilitation Project: State of Implementation and Lessons Learned Presentation at URAM2009, IAEA, Vienna, June 22-26, 2009 16 Lessons learned: Need for clear definition of remediation criteria
I make decisions transparent for authorities and stakeholders as well, to guarantee acceptance in the decision process I develop site-specific remedial measures; no „blind standard application“ With respect to radiation protection: I 1 mSv/a reference value to decide on justification of measures (application of the 10 mSv/a intervention level for existing situations is not accepted by stakeholders) I application of appropriate and for stakeholders easily understandable optimisation procedures (cost-benefit of multi-attribute analyses ?) I 1 mSv/a also as a target ? I radiation protection criteria to be weighed against other criteria !
P. Schmidt et. al. : The WISMUT Rehabilitation Project: State of Implementation and Lessons Learned Presentation at URAM2009, IAEA, Vienna, June 22-26, 2009 17 Lessons learned: Need for proof of effectiveness of remedial measures (1)
Freiberg
Remediation effects to surface waters: U (µg/l)
P. Schmidt et. al. : The WISMUT Rehabilitation Project: State of Implementation and Lessons Learned Presentation at URAM2009, IAEA, Vienna, June 22-26, 2009 18 Lessons learned: Need for proof of effectiveness of remedial measures (2a) July 2002
May 1999
Edelhofweg 7
N Pile # 66/207
Continous measurements with a Rn monitor April before remediation: ø > 1000 Bq/m³ 2003 max. 2500 Bq/m³)
P. Schmidt et. al. : The WISMUT Rehabilitation Project: State of Implementation and Lessons Learned Presentation at URAM2009, IAEA, Vienna, June 22-26, 2009 19 Lessons learned: Need for proof of effectiveness of remedial measures (2b) 3000 25 Rn concentration in 1,5 m height Reshaping: (10/01-03/02) Air temperature in 1,5 m height Covering: (07/02-10/02)
2500 20
2000 15
in in Bq/m³ 1500 10 Rn C Air Air temperature in °C 1000 5
500 0
0 -5 Jul 04 Jul Jul 05 Jul Jul 07 Jul Jul 03 Jul Jul 02 Jul Jul 06 Jul Jul 01 Jul Jul 00 Jul Mai 05 Mai Jan 06 Jan Mai 04 Mai Jan 05 Jan Jan 07 Jan 07 Mai Jan 08 Jan Jan 03 Jan 03 Mai Jan 04 Jan Jan 00 Jan Mai 06 Mai Mrz 08 Mrz Mai 01 Mai Jan 02 Jan 02 Mai Mrz 04 Mrz Mrz 05 Mrz Mai 00 Mai Mrz 07 Mrz Mrz 06 Mrz Jan 01 Jan Mrz 03 Mrz Mrz 02 Mrz Mrz 00 Mrz Mrz 01 Mrz Nov 04 Nov Nov 02 Nov Nov 05 Nov Nov 07 Nov Nov 03 Nov Sep 04 Sep 02 Nov 06 Nov Nov 01 Nov Sep 03 Sep 00 00 Nov Sep 06 Sep 05 Sep 07 Sep 01
Measurement interval
P. Schmidt et. al. : The WISMUT Rehabilitation Project: State of Implementation and Lessons Learned Presentation at URAM2009, IAEA, Vienna, June 22-26, 2009 20 Lessons learned: Not all model predictions materialize ! <=0,2Bq/(m²s) (0,2;0,5] Bq/(m²s) (0,5;1,0] Bq/(m²s) Radon exhalation rate at a big (1,0;2,0] Bq/(m²s) (2,0;5,0] Bq/(m²s) already covered waste rock pile (5,0;10] Bq/(m²s) in Schlema: (10;20] Bq/(m²s) >20 Bq/(m²s)
P. Schmidt et. al. : The WISMUT Rehabilitation Project: State of Implementation and Lessons Learned Presentation at URAM2009, IAEA, Vienna, June 22-26, 2009 21 Lessons learned: New challenges during rehabilitation
Impact of near surface mine gallaries on Ventilation indoor radon was not realized as a problem shaft #382 when WISMUT started rehabilitation works ! 1
Natural ventilation under typical summer weather conditions Shaft 15 IIb (Tmine < Toutdoors;
∆p 1-2 = a few Pa)
500
450
400 River 350 300 stop of ventilation_ weather inversion _ 250
Mulde MS tunnel re-start of ventilation _ 200
150
100 05.06.2003 06.06.2003 07.06.2003 08.06.2003 09.06.2003 10.06.2003 11.06.2003 12.06.2003 50 radon concentration00:00 [kBq/m³]. 00:00 00:00 00:00 00:00 00:00 00:00 00:00 0
time
P. Schmidt et. al. : The WISMUT Rehabilitation Project: State of Implementation and Lessons Learned Presentation at URAM2009, IAEA, Vienna, June 22-26, 2009 22 Lessons learned: Stakeholder involvement and regaining trust of the public are indispensable
Building Bridges with the Public - The WISMUT Policy - • implementation of the project with the staff of the former mining company SDAG WISMUT • involvement of local experts and companies (social factor) • „opening of the books“; openness, frankness, - in particular disclose of data on environmental pollution • involvement of the local public in decision making; stakeholder involvement in general • sustained public relation policy • preservation of mining traditions • returning the WISMUT legacy to productive use (best way to ensure sustainability of remediation)
P. Schmidt et. al. : The WISMUT Rehabilitation Project: State of Implementation and Lessons Learned Presentation at URAM2009, IAEA, Vienna, June 22-26, 2009 23 Lessons learned – “building bridges”
WISMUT Preservation of exhibition hall mining traditions Ronneburg site
Public relation in action: annual on-site “Visitor’s Day”
P. Schmidt et. al. : The WISMUT Rehabilitation Project: State of Implementation and Lessons Learned Presentation at URAM2009, IAEA, Vienna, June 22-26, 2009 24 Lessons learned: Sustainability means returning WISMUT legacies to productive reuse Bad Schlema: Conversion of a devastated uranium mining site back to a radon health spa
Gulf course con- struction on a covered waste rock dump To date, approx. 650 hectares of reclaimed areas have been sold by WISMUT.
P. Schmidt et. al. : The WISMUT Rehabilitation Project: State of Implementation and Lessons Learned Presentation at URAM2009, IAEA, Vienna, June 22-26, 2009 25 Long-term and post-remedial tasks: Post-remedial phase: 5 years = Period during which proof of the efficiency of the performed remediation measures is to be furnished [e.g. accounting for physical modifications that covers will undergo during the post-construction period] Long-term tasks: 30 years (estimate) The long-term and post-remedial activities include: • Water treatment (will need to go on for decades (> 30 years ?)) • Long-term environmental monitoring • Care and maintenance of restored land • Care and maintenance of ancillary mine workings • Mine damage control and compensation • Long-term data management, documentation
P. Schmidt et. al. : The WISMUT Rehabilitation Project: State of Implementation and Lessons Learned Presentation at URAM2009, IAEA, Vienna, June 22-26, 2009 26 Thank you for attention
P. Schmidt et. al. : The WISMUT Rehabilitation Project: State of Implementation and Lessons Learned Presentation at URAM2009, IAEA, Vienna, June 22-26, 2009 27