Siilinjärvi in the context of Heating plant

Surface mining, including strip mining, open-pit mining and mountaintop removal mining, is a broad category of mining in which soil and rock overlying the mineral deposit (the overburden) are removed, in contrast to underground mining, in which the overlying rock is left in place, and the mineral is removed through shafts or tunnels.

In North America, where the majority of surface coal mining occurs, this method began to be used in the mid-16th century and is practiced throughout the world in the mining of many different minerals. In North America, surface mining gained popularity throughout the 20th century, and surface mines now produce most of the coal mined in the United States.

The Finnish national road 9 (Finnish: Valtatie 9, Swedish: Riksväg 9) is a main route. It runs from Turku through Loimaa, Tampere, Jämsä, Jyväskylä, Kuopio, Outokumpu and Joensuu to the Niirala border guard station in Tohmajärvi, right next to the Russian border. The length of the road is 663 kilometres (412 mi).

Apart from the short section right near the center of Turku, highway 9 from Turku to Vuorela of Siilinjärvi is also part of the European route E63, which continues from Kuopio via Kajaani and Kuusamo to Sodankylä. In the case of Jyväskylä, the highway is known as the four-lane Vaajakoski Motorway (Finnish: Vaajakosken moottoritie). The road belongs to the main roads defined by the Ministry of Transport and Communications and to the Trans-European road network.

The Siilinjärvi carbonatite complex is located in central Finland close to the city of Kuopio. It is named after the nearby town of Siilinjärvi, located approximately 5 km west of the southern extension of the complex. Siilinjärvi is the second largest carbonatite complex in Finland after the Sokli formation, and one of the oldest carbonatites on Earth at 2610±4 Ma. The carbonatite complex consists of a roughly 16 km long steeply dipping lenticular body surrounded by granite gneiss. The maximum width of the body is 1.5 km and the surface area is 14.7 km. The complex was discovered in 1950 by the Geological Survey of Finland with help of local mineral collectors. The exploration drilling began in 1958 by Lohjan Kalkkitehdas Oy. Typpi Oy continued drilling between years 1964 and 1967, and Apatiitti Oy drilled from 1967 to 1968. After the drillings, the laboratory and pilot plant work were made. The mine was opened by Kemira Oyj in 1979 as an open pit. The operation was sold to Yara in 2007.

The Siilinjärvi apatite mine is the biggest open pit in Finland. Currently the mine comprises two pits; the larger southern Särkijärvi and the smaller northern Saarinen satellite pit. The Särkijärvi pit is approximately 250 m deep, with a bench height of 28 m. The Saarinen pit is located some 5 km north of the main Särkijärvi pit.