Underground mining is used to access ores and minerals located far beneath the ground when surface mining is not economical. It involves digging tunnels into the earth to extract resources. There are two main types - hard rock mining which extracts metals and gems, and soft rock mining which extracts materials like coal. Access tunnels or shafts are dug and levels are excavated horizontally to reach the ore body. Machinery is used to continue mining and remove material, while supports are installed to prevent cave-ins. Proper ventilation is needed to remove gases and regulate air flow and temperature. Underground mining can be more environmentally friendly than surface mining but is also more hazardous due to safety issues like gas exposure.

1. Mohammad Esa Rasuly
Esarasuly4@gmail.com
III-B.Tech Mining
GIET (A) Rajahmundry

2. Underground mining is a technique used to access ores and
valuable minerals in the ground by digging into the ground to
extract them in an economical way. Underground mining is
carried out when the rocks, minerals, or precious stones are
located at a distance far beneath the ground and it is not
economical to be extracted with surface mining.

3. › The ore deposit is deep.
› Grade is high enough to mine profitably.
› Where surface mining is not economical.
› Certain conditions which surface mining is not permissible such as:
If there is reserve forest.
If there is river flowing beside or one the ore deposit.
If there is habitation area.

4. Depending upon the type of rock the method of working will be chosen.
Underground Mining Methods are usually classified into two categories which
are as follows:
I. Underground Mining (Hard Rock).
II. Underground Mining (Soft Rock).

5. Underground hard rock mining refers to various underground mining techniques used to
excavate hard minerals such as those containing metals like gold, copper, zinc, nickel and lead
or gems such as diamonds.
Underground Gold Mine (Hard Rock) Photo from: www.google.com/images

6. Underground mining (soft rock) refer to a group of underground mining techniques used to
extract minerals such as: coal, oil shale, Salt, Uranium, Phosphate and other minerals or
geological materials from sedimentary ("soft rocks"). Because deposits in sedimentary rocks
are commonly layered and relatively less hard.
Underground Coal Mine (Soft Rock)
Underground coal mine (soft rock) photo from: www.google.com/images

7. Based on Hard Rocks Underground Mining methods can be classified as follows:
• Short-hole and Long-hole Underground Mining Methods.
• Selective and Unselective Underground Mining Methods.
• Supported and Unsupported Underground Mining Methods.

8. Based on the Soft Rocks Underground Mining methods can be classified as follows:
• Longwall Mining Method.
• Shortwall Mining Method.
• Room and Pillar Mining Method.
• Blasting Gallery Mining Method.
• Coal skimming Mining Method .

9. In order to access underground ore minerals removal of overburden is required which can be
done in any of these three ways :
1. Vertical Shaft
2. Decline (or) Ramp
3. Adit

10. Levels are excavated horizontally from decline or shaft to access the ore body. Stopes are then
excavated perpendicular (or near perpendicular) to the level into the ore.

11. › Continues Miner.
› UDM(Universal Drill Machine).
› LHD(Load Haul Dumper).
› Shuttle Cars.
› Belt conveyors .
› Chain conveyors.
› Rope haulages.
› Locomotives.

12. Photos from: www.google.com/Images

14. Photos from: www.google.com/images

15. • Chocks
• Props
• Hydraulic supports
• Roof bolting
• Roof stitching
• Steel arch
Based on the characteristic
of rock, systems of supports
maybe chosen, some types
of supports are as follows:

16. Underground mine ventilation provides
a flow of air to the underground
workings of a mine of sufficient
volume to dilute and remove dust and
noxious gases typically (NOx, SO2,
methane, CO2 and CO) and to regulate
temperature. The source of these gases
are equipment that runs on diesel
engines, blasting with explosives, and
the orebody itself. The largest
component of the operating cost for
mine ventilation is electricity to power
the ventilation fans, which may
account for one third of a typical
underground mine's entire electrical
power cost

17. › Drinking Water:
› Mine water:

18. › Underground mining is more ecofriendly than surface mining and it could
be carried out when the ore deposits are at a higher depth and the various
methods are applicable for extraction of different minerals such as coal,
gold, copper, iron, salt, diamond, etc. in an economical way.
› We should keep in mind that Underground mining is more Hazardous than
surface mining. Noxious gases are present hence we need to take
precautions. In underground mining arrangement should be taken for
lighting, ventilation, support systems, dewatering, etc.
› In Underground mines we can use low and permitted explosives only.

19. › The presenter wish to acknowledge the Management and faculty
members of GIET college specially Mining and Petroleum
branches for providing an opportunity to do this task.
› And also the presenter acknowledge the parents, friends for their
continuous encouragement in doing this work.

20. › http://www.howstuffworks.com
› http://www.google.com
› http://www.google.com/images
› http://www.Wikipedia.org

21. Thank you!