Coal and Mining

Question 1

How is coal formed?

Answer 1

From the burial of land based plant material. This usually takes place in warm tropical environments where there is an abundance of plant material. The plant material dies and is then covered by increasing amounts of sediment and further amounts of plant material. As the plant material is compacted it is subjected to increased heat and pressure.

Question 2

What does increasing heat and pressure lead to into during coal formation?

Answer 2

1. An increase in the Carbon percentage ( rank) in the coal. So higher calorific output ( more heat given off)
2. Less organic matter
3. Denser
4. Harder

Question 3

Name the types of coal.

Answer 3

Peat
Lignite
Sub-bituminous
Bituminous
Anthracite

Question 4

Name the types of mining techniques used for coal extraction.

Answer 4

Opencast
Room and Pillar
Drift Mine (straight across)
Slope Mine
Shaft Mine

Question 5

What is Acid Mine Drainage (AMD)

Answer 5

Caused when water flows over or through sulphur-bearing materials forming acidic solutions. AMD comes mainly from abandoned coal mines and currently active mining and can lead to surface and groundwater pollution.

Question 6

Name the types of subsidence mining control

Answer 6

Grout Injection
Pillar and Rock Bolting

Question 7

What is grout injection?

Answer 7

The compaction grouting process, undertaken by CGS, consists of injecting a low-slump, low-mobility, soil-cement grout at high pressures
to compact loose, coarse-grained soils and densify and/or displace soft fine-grained soils.

Question 8

Name types of sustainable mining management

Answer 8

Collect water which falls in rainy season
Laterite on road surfaces
Re - vegetation on Landscapes
Dust Control
Noise monitoring equipment
Noise Control
Water Filtration

Question 9

Describe the case study of Aberfan 21st Oct 1966

Answer 9

Tipping began above the village in 1916 when more easily accessible sites lower in the valley became exhausted, creating seven distinct mounds by 1966. In the aftermath of the disaster most of the spoil was removed to Cnwc
tip on Mynydd Merthyr and the remaining spoil at Aberfan reshaped to the current profile. Stability was improved by two drainage tunnels, to draw water from the aquifer below the tip. After re-grading, the tip was grassed and has
for a long time been let for grazing under an agricultural tenancy.