"Our officials have found severe violations of the Act during a spot inspection. Emissions of pollutants are found to be very high in some of these units. We have decided to move court against a few of the industries," said Achyut Mishra, MPPCB regional officer.

"With the increase in steel prices and competition from large-scale units, many re-rolling mills here are shifting from furnace oil to coal as industrial fuel to save input costs," he said.

Rajasthan Steel Industries, National Steel and Iron works, Thermal Industries, Sanjay Machinery and Tools, Madhyanchal Steels, PR Enterprises, Khumai Steels, Mohammad Rafiq Rolling Mill and Forbos Industries are among those units to which notices were served.

However, unit insiders admit that though the use of steel grade coal as burning fuel was leading to an increase in air pollution, wide difference between the price of furnace oil and coal was encouraging the units to the use of coal.

According to MPPCB, there are about 40 re-rolling mills working around Indore and Sanwer. About 80 per cent of rolling mill owners have now installed pulverizers and burn steel grade coal to heat the raw material and ingots. Though furnace oil is the approved fuel for the industry, most of the units are using coal to save money, which has caused rise in the pollution, they say.

The industrialists, however, maintained that they were using coal partially and to meet the challenge of increasing prices of furnace oil.

Sham Sunder, an industrialist, said the cost of furnace oil fuel had substantially increased recently. "While coal was available at about Rs 4 to Rs 6 per kg, the furnace oil has to be procured at Rs 14 per litre. We have to use about 40 litre of furnace oil costing Rs 560 to produce one tonne of steel," he said.

About 70 kg of coal costing Rs 280 will be used for the production of one tonne steel. The use of coal will save about Rs 280 per tonne, thus encouraging the industry to use it.

According to an estimate, each unit working for eight hour was saving Rs 17,000 every day by using low quality fuel. The insiders point out that the rolling mills are illegally procuring steel grade coal from brick-kiln owners. The units have installed coal grinding machines which are used to grind coal to make it powdered fuel for burning/heat the furnaces.

Whatever excuses these unit owners might have, MPPCB has got video footages and several other proofs to establish their charges against them.