Overview of the MDPA mine operator contract and its context


The MDPA (Mines de Potasse d’Alsace) is a public company in voluntary liquidation and the French State is its sole shareholder. It is focused on the permanent closure of the Stocamine underground final waste storage repository located in the underground galleries of the Joseph-Else mine in WITTELSHEIM (68).

Partial removal operations (94% mercury) were completed at the end of 2017, and confinement operations were authorised by Bylaw on 23 March 2017.
This decision was taken after several studies, assessments, third party inspection and a public inquiry.

MDPA were ordered to conduct a further waste removal feasibility study without restricting confinement by the French environment minister at the start of 2019. The results of this study, entrusted to a specialised engineering consultancy, are expected mid-2020.

The site is approximately 550 m deep in layers of salt rock formation. It is accessible via two vertical shafts. The storage site is classified as intermittently susceptible to fire-damp which requires the use of ATEX category M1 or M2 equipment, proven experience in similar environments, in mines or underground work, and specific skills.

The waste is stored in hermetically sealed blocks. It is non-radioactive, final, industrial waste. Confinement operations have begun. These involve isolating the storage site by positioning 12 isolation plugs at the entrance to each storage pit and backfilling the empty blocks and galleries with approximately 100,000 m3 of concrete and salt. The aim of this solution, thought up by national and international experts, is to ensure the safety of the repository with respect to the environment and, more specifically, to protect the Alsace aquifer by isolating the storage site from the biosphere.

Once confinement is complete, and after a monitoring phase expected to last until 2027, the operations shall conclude with the dismantling of the installations and permanent closure of the site after backfilling the shafts.

The contract involves the operation and maintenance of the MDPA installations so that the closure work can be carried out in the best possible conditions.

The contract is broken down into three items:

  •  Operation and maintenance of the shafts,

  • Maintenance of the galleries and mining equipment, management of underground ventilation,

  • Electrical distribution and maintenance of electrical cables and remote monitoring/sensors networks. 

The three items can be allocated separately and companies will have the option of bidding for all three of the items.

The service provider will have to independently oversee their assignment and take full responsibility. Their specific technical skills must be sufficient to manage all of the functions including supervision, coordination, methods, planning, safety, procedures, inspection, quality, purchasing, etc. This shall be done in coordination with the MDPA technical, work and maintenance team who will act as the interface with the companies responsible for the closure operations.

The MDPA installations are specific: they date back to the time of potash mining up until the 1980s and have been almost entirely renovated for the closure operations. The mine is classified as intermittently liable to fire-damp. These three points call for highly specialised personnel who must be specially trained on the installations.

The assignment consists of several different phases:

  • The first, as part of a reimbursed inventory and statement of state of repair, during the tender phase, for the chosen applicants with the best references,
 The second, called the appropriation phase, over the first three months, 

  • The third, known as the take-over phase, over the next three months before the contract holder 
is fully operational. 

The closure operations are unique and innovative:

the closure of this kind of storage site is a first in Europe and requires a high level of technical expertise for the installation of very low-permeability barriers made of special concrete with strict requirements at great depth, and for the transportation of 100,000 cubic meters of liquid backfill through pipes. This technical nature requires the wealth of expertise of the Project Manager and of a large, internationally recognised construction company. The same level of expertise is expected from the mine operator, in order to support the operations by ensuring maximum availability of the installations and by enabling the various different parties to work in a safe environment. 

The chosen procedure is an open tender with negotiation (mixed-fee public works contract). It will proceed as follows: 

  1. Release of a pre-information memo 

  2. Release of the call for tenders (current phase) 

  3. Release of the company consultation file 

  4. Submission and evaluation of the tenders 

  5. Negotiation and allocation 

The contracts are scheduled to be allocated in January 2021.

The contract is a mixed-fee public works contract, consisting of:

  • A monthly fixed rate for maintenance and operating indexed to the various different phases of the site’s activity. I will include labour costs, including the materials and tools required. MDPA shall provide the Contract Holder with their mining machines (digging and dinting machine, bolters, etc.) and all their equipment. Materials, parts and consumables shall be purchased after a tender process, then invoiced to MDPA with a hardship coefficient. 

  • A price schedule for works not included in the fixed price contract if required.

Companies interested in applying can make themselves known to the contracting authority MDPA by sending an email Stéphanie ZAMPIERI : contact@achats-economiz.com (specify object  : MDPA – Mission d’opérateur Minier).

Avenue Joseph Else
Tél. : +33 3 89 57 87 12
SIRET 38116674300017 / RCS Mulhouse B 381 166 74