**5. Implementation**

#### *5.1. Case Study: Restoration Project Overview*

The case study refers to a restoration project of a continuous surface mine, including two lignite fields (Mine I and Mine II, Figure 2) planned for the exploitation of a lignite deposit located in northern Greece. Between the two mining fields a ridge is found with no lignite occurrence. The mining site is hilly, with surface altitudes ranging between 700 m–900 m above sea level. At the western boundary of the mining area, there is a village with 100 inhabitants. The mine contributes in meeting the lignite demand of a power plant located 12 km west of the mining area.

The lignite basin has a channeled form and it is broadened from the NE to the SW direction, along with local increases of surface elevations. The area of mining activity covers approximately 10 km2. The deposit is of a multiple-layered form, and lignite seams are almost horizontally bedded. However, a series of normal faults results in a progressive and systematic deepening of the beds and in a corresponding increase the thickness of overburden material towards the SE rim of the basin. The main characteristic of the deposit is the occurrence of conglomerate hard material in the overburden formations.

The strategic mine development, including the two outside dumping areas, is shown in Figure 3. The main outside waste dumping area is located 1.5 km NW from the mine. The sequence of mining operations, considering time periods of 10 years, from the initial to the mine closure stage, is presented in Figure 4.

The main mining equipment consists of bucket wheel excavators, conveyors and spreaders and the decision making regards the optimal restoration of the mine after 25 years of operation, while its remaining life is 10 years. At this stage, the waste material of the excavation activities is transported to the inside dumping area. Following the mine closure plan, a lake was planned to fill the existing area voids.

**Figure 2.** General overview of the mining area, including the boundaries of the two lignite fields (Mine I and Mine II).

**Figure 3.** Strategic mine development.

**Figure 4.** Sequence of mine development in the cross section A-A' of Figure 2.
