Kolkata, Jun 8 (IANS): The West Bengal government is exploring the option of underground mining for "world's second largest" coal block, Deocha Pachami, in the state as the conventional open cast would be a challenge, a state Minister said on Friday.

"Deocha Pachami coal block was allocated to us. There is a stone block above the coal seams. I recently went to Poland to understand the technical know-how to excavate coal below the stone block. Poland is technically sound," state Power Minister Sobhandeb Chattopadhyay said.

Deocha Pachami Dewanganj Harisingha has reserves of 2,102 million tonnes of coal and is spread across 21 villages in Birbhum district.

"I am very happy to share with all of you that after a long wait of 3 years, #Bengal has got the allocation of the Deocha Pachami Harinsingha Dewanganj Coal Mines in Birbhum district," state Chief Minister Mamata Banerjee said in a tweet on Friday.

She said the mining project has huge potential of generating nearly a lakh of direct and indirect employment opportunities in Birbhum and neighbouring districts.

"It will also involve investments worth Rs 12,000 crore in the intermediate run," Banerjee said.

"Open cast mining at the block isn't possible. We have to go for underground mining. However, the project is at the initial stage," he said on the sidelines of the "East India Energy Forum" organised by the Merchants Chamber of Commerce and Industry.

However, Banerjee said "necessary administrative infrastructure" has already been set up to start the project immediately.

Besides West Bengal, the block was initially allocated to Karnataka, Bihar, Punjab, Tamil Nadu and Uttar Pradesh, along with public sector undertaking Satluj Jal Vidyut Nigam Ltd.

"Other states are reluctant to continue and now, it is allocated to us," the Minister said.

Industry sources earlier pointed to the issue of the cost factor to lift coal out of the block as the coal seams are concealed under a thick cover of stone.

The Minister also said that the Power Department is planning to complete underground cabling in 75 cities in the state by 2025 to reduce transmission losses and improve the quality power.

According to Chattopadhyay, around Rs 15,000 crore would be invested in various power projects in the state in the coming years.

He said the state was not able to go for large solar projects due to land constraints. However, the installed solar capacity would be up to 200 megawatt within 2019 from the present level of 70 megawatt.