Asse II Mine – Retrieval of the Waste Taking into Account the Best Possible Emergency Preparedness

Matthias MohlfeldFederal Office for Radiation

Protection (BfS), Germany

Washington, DCSeptember 7-9, 2016

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Key Data

BerlinHannover

Hamburg

Köln

München

Frankfurt

Leipzig

Asse II salt

Asse II mine Waste emplacement: 1967-78

Low and intermediate level waste

Brine inflow from the overburden rock since 1988

Intended option for decommissioning: Retrieval

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The Mine

A “research mine” that should never have

been used for the disposal of radioactive

waste.

The Asse II mine. The fault. The problem. The task.

Four Steps - One Problem.

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Asse II – The Mine

The Asse II mine. The fault. The problem. The task.

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Mining vs. Disposal

Purpose of mines Purpose of repositories

Maximal extraction of raw materials Safe enclosure of radioactive waste

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The Asse - A Salt-Mining Region

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Asse II – The Fault

The Asse II mine. The fault. The problem. The task.

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Emplacement

EC 8/750 (1975)

EC 4/750 (1968)

EC 7/750 (1978)

EC 8a/511 (1987)

Period

1967 – 1978

Volume

125,787 waste packages / ca. 47,000 cubic meters

Type of waste

Low- and medium-level radioactive waste

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Asse II – The Problem

The Asse II mine. The fault. The problem. The task.

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The Mountain Is Moving

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Inflow of Brines since 1988

1988, 532 m

Since 1998 the collected brine rate is about 12 m³/d

Brine is almost saturated

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Asse II – The Task

The Asse II mine. The fault. The problem. The task.

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Decommissioning According tothe Atomic Energy Act (AtG)

2009§ 57b AtG

„The Asse II mine shall be decommissioned immediately.“

2009 - 2010

2013

Retrieval Relocation Backfilling

§ 57b AtG

„The Asse II mine shall be decommissioned immediately. […]The Asse II mine shall be decommissioned after the retrieval of the radioactive waste.“

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Tasks of the BfS

Decomissioning of the mine

Stabilisation and emergency

preparedness

Operation of the mine under nuclear law and mining law

Tasks of the BfS

Shaft 5

Fact-findingInterim storage facility

Retrieval machinery

Infrastructure

Retrieval of the waste

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Stabilisation and Emergency Preparedness -

Measures to stabilise the mine openings and to protect the emplacement chambers:• to continue safe operation• to maintain the integrity as best as possible• to achieve the best possible emergency preparedness in the event of

an increase in brine inflow • to keep the basis for the retrieval of the waste

Prepatory measures for fast reaction in the event of an emergency:• for fullfilling the waste chambers• for flooding the mine with saturated brine• for stabilizing the mine with compressed air• for the shaft closures

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The Mine Today

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Exploration Shaft 5

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Interim Storage Facility

Storage area with buffer store

Salt processing

Collection of waste water

Workshop and decontamination

Store for additives

Supply building

Waste package acceptance

Conditioning

Drying Measurement hall

Office and social buildings

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Demands and Contradictions

Retrieval? - Immediately!

Interim storage facility? - Nimby!

Disposal at Konrad Repository? - No!

Retrieval? - Mission impossible!

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Asse Decommissioning Project – Time Schedule

Planning / construction shaft 5

Retrieval

Fact finding step 1 - drilling

Emergency preparedness and remediation

Planning / construction of interim storage facility incl. conditioning

“Lex-Asse”: Retrieval legally laid down as decommissioning option to be pursued. Enables parallel action (to invest before the results of the fact finding are available)

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Thank you!