The extraction of iron ore usually takes place in open quarries and extends over large areas, which means that the groundwater situation can change and local ecosystems can be damaged. One ton of iron ore usually produces 5 to 6 tons of waste materials. Extraction of coal in open quarries or deep mines causes similar environmental damage.

The conversion from iron ore to steel requires a series of processes. They begin with the breaking up of the ore, then cleaning, followed by sintering. The iron is smelted out and reduced in a blast furnace at 1700–1800 ^oC. A large, modern blast furnace can produce 1000 tons of pig iron every 24 hours. The amount of air needed is fourmillion cubic metres, and the coolingwater is equivalent to the amount a small town would use. It takes 440–600 tons of coal to produce 1 ton of iron. The total amount of coal needed can be halved if an oil spray is injected intothe furnace. Coal is used in the process to remove oxygen fromthe ore by forming carbon dioxide, leaving the pig iron behind. Limestone is added to the blast furnace charge in order to bind ash, silica, manganese, phosphor, sulphur and other impurities. This slag can, in turn, be used as pozzolana in the production of cements.

Steel can be made from pig iron and steel scrap. Most of the carbon in the iron is released through different methods, e.g. oxidizing. This is done in blast furnaces or electric arc furnaces. The latter is often used insmaller-scale facilities, consumes less energy, howevermainly as electricity, and represents 30–40% of the world’s production today. Steel production in electric arc furnaces can also be based on 100% steel scrap, while other production methods only permit a fraction of scrap. Finally, the steel is rolled out to produce stanchions, beams, pipes, sheeting and nails.

Large amounts of the greenhouse gas carbon dioxide, as well as sulphur dioxide, fluorine compounds, dust and a wide range of heavy metals are emitted in the production of pig iron. The carbon dioxide comes partly from the combustion of coal in the reduction process and also as chemical emissions from the burning of admixtures of lime-stone. The net emission of carbon dioxide as well as sulphur dioxide can be significantly reduced by replacing mineral coal with a maximum of charcoal in the reduction process (30–40%). This is done in Brazilian iron production. The charcoal can even bemixed inwithwood chips to a certain extent.

In the production of steel emissions of carbon dioxide will be large, but in general significantly lower for electric arc furnaces than for blast furnace technology (Kram et al., 2001). Other available methods for reducing energy consumption and carbon dioxide emissions in steel production include direct reduction and iron bath smelting but these are not yet economical.

The toxic element arsenic is well bound in the iron ore, but with a second smelting from steel scrap a good deal is released. Production from scrap iron also causes emissions from other compounds in the scrap, and considerable release of polycyclic aromatic hydrocarbons (PAH) and dioxins can be expected. When producing from stainlesssteel, there will be a larger release of nickel and chrome.

Steel scrap is virtually inert, but ions from iron and other metal alloys can leak into water and soil. Serious pollutants can also include waste materials from surface treatments, paint or fire protection coatings