(a) Study Fig. 4 which is a diagram of a coal mine. [Figure 4] (i) Choose two terms from the list below and use them to label the diagram in any two of the spaces provided. adit cage shaft open-cast seam tunnel (ii) Suggest two reasons for using this type of mine and one disadvantage of using it. Reason Reason Disadvantage (iii) What type of coal is imported by Pakistan and how is it used? Type Use (b) Explain what the fuel CNG is and state the main reasons for using this fuel. (c) Study Fig. 5 which is a graph giving information about different non-renewable fuels used for electricity production in Pakistan over the period 2006–11. [Figure 5] (i) What is meant by the term 'non-renewable fuel'?

Mark scheme

Marking points from the official mark scheme (Oct/Nov 2016). The mark or mark type is shown in brackets.

1. [2] Any two of (left to right): cage, tunnel, shaft, seam, shaft, (type of mine)
2. [3] Reasons - 2 marks To access seams deep below surface To access seams of different depths Can exploit further along the seams Where seam does not appear at / near surface / hillside Disadvantage - 1 mark More expensive Greater risk of accident / flooding / gas build-up – credit all reasonable ways that accidents can happen Dependent on [power for] lift to the surface
3. [2] Type: Anthracite / bituminous – 1 mark Use: Steel industry / heavy engineering / smelting – 1 mark
4. [4] Definition - Reserve 1 mark Compressed natural gas Gas compressed to 1% volume it has at normal pressure Methane under high pressure Reasons - Reserve 1 mark Used (instead of petrol / diesel) in transport / vehicles Especially buses / rickshaws (Compared to petrol / diesel) cheaper, cleaner / reduces air pollution, safer Can be stored / transported in cylinders
5. [2] An energy source that depletes / runs out / is not being replaced / has fixed reserves / is finite - 1 mark With any one example e.g. fossil fuels, wood, coal, oil – 1 mark
6. [1] Oil
7. [2] Gas overall decrease: oil overall (throughout / 2006–2011 / over the years) increase Gas from 36 to 27–28 TWh / by 8–9 TWh: oil from 27-28 to 33–34 TWh / by 6–7 TWh Reserve 1 mark for use of data with unit (TWh)
8. [3] Coal mined in Pakistan is unsuitable Lignite, sub-bituminous to peat Contains impurities / sulfur Low heat producing, low carbon content, large amount of ash, does not give out much energy Coal reserves not exploited due to shortage of funds / technical skills Not imported (because expensive) Difficult / expensive to transport around country because bulky International agreements / pressure to use less coal since is a dirty fuel / causes high emissions of smoke / CO2
9. L3 5-6 marks 6 – Developed points addressing measures taken and the extent of their success with evaluation 5 – Developed points addressing measures taken and the extent of their success L2 3-4 marks 4 – Two developed point(s) addressing any measure 3 – Developed point addressing any measure L1 1-2 marks 2 – Two simple point(s) addressing any measure 1 – Simple point addressing any measure 0 – No valid response Indicative content (development of points in parentheses) Measures Moving away from non-renewable / large-scale schemes to renewable / small-scale schemes E.g. wind, solar, biogas (details / examples) Investment in large-scale power stations E.g. nuclear, wind, solar, HEP, gas, coal gas (details / examples) Energy saving in workplaces / homes Public / media awareness about not wasting energy resources Evaluation (depends on measures) Successful Small-scale schemes can be maintained locally / in rural areas Given sufficient government / private / foreign investment Wind - large empty areas of uplands / Makran coast Solar - lack of cloud (250–300 sunny days per year) Biogas - large agricultural sector producing manure / plant waste Unsuccessful Opposition to new technology / power stations High cost (leading to domestic / foreign debt) Changes of government priorities (large projects may be delayed / cancelled) Limited skills / expertise (in using advanced technology) Other issues considered higher priority than saving energy (e.g. escaping poverty / increasing levels of education / health) Hydro in north – far from the major centres of population, transport costs Green energy is less reliable