Coal used for this process is called steaming coal. In 2008 77% of the electricity generated in Australia was produced by coal fired power stations (includes black and brown coals). Some types of black coal are suitable for coke-making.
These symptoms may occur in the back, leg and down to the foot. The most common nerve irritation originating from the lumbar spine is Sciatica. This is an irritation of the sciatic nerve, which can produce pain, numbness, and weakness down the leg along the areas innervated by the sciatic nerve.
For example: 1  L4 nerve root sciatica symptoms usually affect the thigh. 2  L5 nerve root sciatica symptoms may extend to the big toe and ankle (called foot drop). 3  S1 nerve root sciatica affects the outer part of the foot, which may radiate to the little toe or toes.