FR_Andra_1

LS-Andra - Meuse/Haute-Marne Underground Laboratory

Facility Location
City & country
55290 Bure (France)
RD 960, BP9
Description & contacts of the access provider
Legal name of organisation
Andra - Andra
Infrastructure contact - Primary contact
Gilles Armand
RICC contact - Secondary contact
Emilia HURET
Facility Availability
Unit of access
Weeks
Availability per year
The experiment may be available all year round and the data are remotely accessible.
Expected duration of single experiment:
Depend on the experiment, but a few years is a common duration.
Operational or other constraints
Specific risks:
-Respect of safety rules defined by Andra, wear safety equipment, French medical ability for underground works; -In case of need to use supercritical CO2, a meeting with safety engineer will be necessary to define this possibility -The concept of the experimental set-up should be validated by Andra for safety reasons and co-activity management.
Legal issues
No general issues

Purpose

Since 1999, Andra has been investigating and characterizing the Callovo-Oxfordian clay layer which could host a reversible deep geological disposal for High-level and Intermediate-Level Long-Lived radioactive Waste (Cigéo project). The site selected is located on the eastern boundary of the Paris Basin (Meuse/Haute Marne region). Claystone formations, due to in particular a very low permeability and high confining properties, are indeed candidates to host a radioactive waste disposal. In this region, the Callovo-Oxfordian formation lies between around 420 m to 600 m deep, and its thickness is at least about 130 m. The Callovo-Oxfordian formation is surrounded by two main calcareous formations (Dogger and Oxfordian). The characterization studies are carried out thoroughly in a specific site where is implemented an Underground Research Laboratory within the Callovo-Oxfordian formation, called “Meuse/Haute Marne URL” (MHM URL).

More than 15 years of research and development works have been carrying out in this URL to support the main milestones and reports of the Cigéo project. The MHM URL will continue to play a key role for the next steps of the Cigéo project. Due to an important network of drifts available (Figure 1), the MHM URL could be open for experiments not focused on radioactive waste management such as CO2 studies in the framework of ECCSEL. The MHM URL has been granted to operate until 2030 allowing to envisage long term experiment if required.

 

Brief technical description

The MHM URL consists of (Figure 1):

  • 2 shafts of 500 m (one of 4 m and the other of 5 m of diameter);
  • 1 drift 40 m long at –445m (upper part of Callovo-Oxfordian clay formation, more rich in calcite) from the ground surface;
  • A current network of 1.7 km of drifts located at – 490m (corresponding to the middle of the clay layer with the highest clay minerals content). The sections of drift vary between 18 and 60 m2 according to scientific and technological objectives. About 850 boreholes been drilled in all directions (vertical up and down, horizontal, oblique) up to 100 m long, in a wide range of diameter between 22 mm and 350 mm. The purposes of these boreholes are very large (Figure 2):
  • R&D objectives: geological survey, hydrogeological, geochemical, microbiological and rock mechanical studies;
  • Characterisation of anthropic impacts: temperature, excavation and ventilation, alkaline plume etc.;
  • Technical aims: excavation and support (lining) techniques.

More than 11 000 sensors have been installed in the rock, inside boreholes, in the drifts, in the shafts, allowing a continuous monitoring at distance. The type of sensors tested is very large according to concerned Thermal, Hydraulic, Mechanical, Chemical and Radiological domains: from very classical sensors (ex. pressure/temperature) to the development of innovative optic fibre with distributed measurements and sensors for thermal and mechanical long term monitoring.

Specifically for fluids, experiences in continuous pH and redox measurements are online. Direct analyses (by chromatography or spectrometry) underground are also possible.

Hydro-mechanical and geochemical characterisations of clay (deep) formations are commonly assessed in the context of nuclear waste geological repository and could be easily adapted to CO2 storage experiments where clay plays the role of cap-rock in this case. Hydro-mechanical responses of clay solicited by gas injection have been conducted in the MHM URL in order to assess hydro-fracturing characteristics of the Callovo Oxfordian clay formation. This in situ large scale gas injection test called PGZ experiment, started in 2009, allows us to investigate gas migration mechanisms in clay materials and to define in particular:

  • Gas entry pressure
  • Gas pathway dilation
  • Gas migration parameters at large scale
  • Fracturing pressure

Thus, N2 was injected at various pressure steps up to 98 bars and the data collected might be used for CO2 injection experiments. The MHM URL has also a good experience in the field of microbiological and geochemical experiments (cleaning procedures for drilling tools and borehole equipment, use of argon as drilling fluid to avoid oxygen impact, download equipment made exclusively of inert material, sampling protocols) and to study these processes with in situ conditions (PAC, BAC, POX experiments).

 

The current MHM URL network consisting in 1.7 km of drifts and about 850 boreholes (various colour lines).
Examples of equipment at the facility
Examples of equipment at the facility
Examples of equipment at the facility
Andra's network of collaboration
State of the art, uniqueness, & specific advantages

In France, the MHM URL is the only facility accessible for in situ experiments in a deep clay formation at 500 m depth, with a hydraulic pressure of 46 bars and a vertical stress of 12 MPa, allowing to perform different tests from small scale to large scale and in representative conditions of these ones of a cap-rock for capture and storage CO2 concept.

Andra has collected a large number of data concerning the properties of the Callovo-oxfordian clays at different scales (I.e. from the pore scale up to the scale of the geological formation) which will be available to support new projects. Surrounding calcareous formation were also investigated. Thus, the geological environment is already well defined and it would not be required to plan a lot of analyses to be characterised. The overall operating and maintenance works of the MHM URL is operated by Andra. This high cost will not be charged on ECCSEL projects.

Scientific Environment

The MHM URL benefits from the support of Andra’s technicians and engineers: 40 scientists of Andra specialized in geology, rock mechanic, hydrogeology, chemistry, fluid transfer, biology, corrosion, sensors and data acquisition system, work on site. A specific team provides support in designing and setting up experiments. Several contractors used to work in the MHM URL can give support in specific domains (drilling, geological survey and sampling, chemical, biological and mineral characterizations). It’s also possible to perform in situ gas and fluid analyses (by ionic chromatography, or Raman spectrometry…). Andra has also a hall for technological demonstrators on MHM centre that could be accessible to people involved in ECCSEL projects.

To achieve all objectives, Andra has developed an important network of collaboration with others scientific partners as experts in their domains (figure 3).

selected publications

De La Vaissière R., Armand G., Talandier J. (2015)
Gas and water flow in an excavation-induced fracture network around an underground drift: A case study for a radioactive waste repository in clay rock
Journal of Hydrology, 521, 141-156
Cailteau C., Pironon J., De Donato P., Vinsot A., Fierz T., Garnier C., Berreso O. (2011)
FT-IR metrology aspects for on-line monitoring of CO2 and CH4 in underground laboratory conditions
Analytical methods, 3, 877-887
- De La Vaissière R., Gérard P., Radu J.P., Charlier R., Collin F., Granet S., Piedevache M., Helminger B. (2014)
Gas injection test in the Callovo-Oxfordian claystone: data analysis and numerical modelling
Geological Society of London, special publications, on line