Lisheen closure and rehabilitation

Mining at Vedanta’s Lisheen Mine in Tipperary, Ireland, ceased at the end of 2015, after 17 years of operation. The cessation of mining at Lisheen was not the end of the story as far as we are concerned. From the beginning, Vedanta had always planned for the closure and successful rehabilitation of the Lisheen site.

Focusing on physical closure of the mine and aftercare of the site, a best practice mine closure plan was implemented to fully address all regulatory authority permit requirements. Lisheen’s closure programme is believed to be among the world’s finest examples of environmentally sensitive mine closure and rehabilitation.

Site rehabilitation work included:

  • Ensuring that the underground workings cannot collapse leading to surface subsidence
  • Removing all surface and underground plant and equipment
  • Allowing the mine workings to refill with clean water
  • Blocking and sealing all access to the underground workings
  • Fully engineered covering of the tailings deposition facility to provide a multiple of possible after-uses, from animal grazing to solar power or energy crops
  • Creating a space that will be attractive to other industries
  • Supporting Lisheen staff during the closure, from upskilling and training grants to redeployment at other Vedanta operations

Lisheen’s management and a task force appointed by the Irish Government worked with a range of stakeholders to redevelop the site as a National Bioeconomy Campus. At Lisheen, Vedanta committed to ensure that a safe and secure site would be left behind, and to strive to provide replacement industry on the site with all the social benefits that this brings.

In December 2017, the Irish Government announced substantial funding to establish a bioeconomy innovation and piloting at Lisheen. The next stage of the site’s life is well underway, as a result of our commitment to world-class closure and rehabilitation.

Tailings management

Lisheen Mine started a progressive rehabilitation programme in the early 2000s as part of its Closure, Rehabilitation & Aftercare Management Plan (CRAMP) which was fully approved by all regulatory authorities. The TMF rehabilitation works consisted of a 1m thick hybrid cap being placed over the tailings, with each element of the cap fulfilling a specific function. The first layer was a geotextile, followed by 700mm of limestone rock and then 300 to 400mm of soil, covered with grass to form a stable and sustainable surface. A system of spillways was installed to manage water on the facility. A certain amount of water is maintained within the rock cap, just above the elevation of the tailings, to make sure they are kept moist and will not oxidise to produce acid mine drainage.

Assurance

The TMF remains governed by the conditions of Lisheen Mine’s Integrated Pollution Control Licence (IPCL) which requires ongoing monitoring and auditing of the facility into the future. An emergency plan has been developed and details the actions to be taken in the event of failure. A detailed aftercare programme has been developed for the Lisheen Mine and agreed with the Environmental Protection Agency (EPA). The plan is subject to annual review and the requirements may increase, depending on monitoring data or any other developments.

During its operation, the TMF was audited annually by competent engineers who were considered to be ‘All Reservoir Panel Engineer’ equivalent and this auditing remains a requirement of the aftercare plan. Scheduled monitoring is carried out to assess both the stability of the facility and the potential impact on the environment (surface and groundwater) and the results of this monitoring is submitted to the EPA at the required frequency.

The aftercare plan, as currently agreed, is fully funded and all monies are secured with signatures from both the company and the EPA required to make withdrawals.