Construction and evaluation of mine cover systems with upgraded soil - Experience gained from laboratory and pilot

Purpose and goal:

The overall aim of the project is to facilitate the design of mine reclamation measures, providing a methodology but also practical recommendations (dos and don’ts) to guide compagnies through the design and construction of sealing layer built with amended upgraded soil.

The main scientific objective is to test and validate a stepwise method to design of mine covers, based on column experiments (easier and cheaper to replicate) and field tests (to validate the proposed reclamation solution in real conditions), complemented by numerical simulations. Expected results and effects:

The main result of the project is a stepwise cost-efficient methodology to develop sealing layer based on upgraded materials and assess their performance from laboratory to demo. The method is rapid and cheap compared to traditional pilot/field experiments to screen possible materials and design. One expected outcome is an enhanced development of innovative solutions based on ameliorated local soil materials of lower quality, limiting the need for transportation of clayey soil. Combined to numerical modeling, it can be used to assess performances under various condition.

Approach and implementation:

The project is divided in two main activities i) a scientific evaluation based on both laboratory experiments and field tests, complemented by numerical simulations of four mine cover designs where the sealing layer was built with a glacial till that originally did not meet requirements ii) a compilation of experience working with material characterization, construction and instrumentation of columns and pilot experiments performed during the last decade, describing also challenges and misfortune associated with e.g. valorization of waste streams in such applications.