environmental pollution past papers
Use examples to explain the following terms, as applied to pollution. (a) Persistence. (2 marks) (b) Bio-magnification. (2 marks)
(a) Length of time a pollutant remains in environment (before it degrades/breaks down); [A description based on more persistent] example of pollutant to illustrate - organochlorines/PCBs/CFCs/dioxins/sewage/radioisotopes or other suitable example; 2 [R pollutants that don't degrade] (b) Concentrated when passed to next trophic level/up a food chain; example of pollutant to illustrate - organochlorines/PCBs/dioxins/heavy metals or other suitable example;
Write an essay on one of the following topics. Credit will be given for your understanding of the relationship between different areas of the subject, also for the organisation and presentation of the essay and use of grammar, punctuation and spelling. EITHER (a) Describe the ways in which pollution may threaten the life-support systems of the planet. OR (b) Explain how a policy of sustainable exploitation of the planet's resources would help to reduce the quantity of pollutants released. 20marks
(a) Named life support systems (LSS) e.g. atmospheric processes, species interrelationships, water cycle, soil details of how LSS functions named pollutant/pollution issue e.g. ozone depletions, GCC, acid rain, species extinctions, soil contamination, eutrophication, water deoxygenation details of impact of pollutant(s) on LSS [R pollutant sources methods of pollution prevention non-pollution threats to LSS e.g. deforestation pollutants which do not threaten LSS e.g. CO, asbestos] (b) Definition of sustainability unsustainable activities activity/pollutant effects Sustainable strategies/policies Name/e.g. Rio Summit/Agenda 21 Details Renewable resource use energy plant and animal products Energy conservation Reduced consumerism/refuse - reduce - reuse - recycle Manufacturing strategies - long lifetime/not planned obsolescence Re-cycling material reduced extraction processing waste disposal Reduced impact agriculture habitat impact nutrient supply pest control seasonal/local supplies
Use examples to explain the following terms, as applied to pollution. (b) Bio-magnification. (2 marks)
(b) Concentrated when passed to next trophic level/up a food chain; example of pollutant to illustrate - organochlorines/PCBs/dioxins/heavy metals or other suitable example;
Batteries that use mercury are banned in most countries. Why are greater safety precautions needed when using organic mercury compounds than when using inorganic mercury compounds? [1 mark]
(organic) more toxic/more completely absorbed/transferred across cell membrane/(more) liposoluble/(more) volatile
Use the flow diagram to select a suitable test to assess the statistical significance of the effect of noise on educational performance in English. 1 mark
) Spearman's Rank (Correlation Coefficient);
It was concluded that the relationship between noise levels and performance in mathematics was statistically significant at the p = 0.05 level, but that the relationship between noise levels and creative writing was not. Explain what is meant by the term statistically significant at the p = 0.05 level. 1 mark
5% probability that the results were produced by chance/95% probability that the results were not produced by chance;
State one major factor that affects the maximum potential for future expansion of the following renewable energy resources. 6 (d) (ii) HEP (1 mark)
6(d)(ii) HEP - few suitable sites/habitat loss/small catchment areas/ permeable rocks/unsuitable topography/land use conflict; [A named technological development]
State one major factor that affects the maximum potential for future expansion of the following renewable energy resources. 6 (d) (iv) Biomass (1 mark
6(d)(iv) Biomass - land availability/competition (with food)/habitat loss; [A named technological development]
What is the effect on the power output of: 6 (a) (i) doubling wind speed 1 mark
8x
Outline how ozone is environmentally important in the following. 2 (a) (i) the stratosphere 1 mark
Absorbs UV/prevents skin cancer/named health problem; [A reduces UV reaching Earth]
Explain how the noise pollution experienced by residents near an airport could be reduced. 2 marks
Absorption/insulation/deflection/reflection of noise; example of technique: baffle mounds/embankments/double glazing/bund/fencing;
For a company to gain the consent of the Environment Agency to release a new effluent into a river it may be necessary to treat the effluent before its release. (a) Describe how such an effluent may be treated to reduce its heavy metal content. (2 marks)
Add lime/other alkali/raise pH; reduces solubility/precipitated as solids; suspended particles; tailing dams/sedimentation/centrifugation; reedbeds/bacteria; absorption/bioaccumulation; phosphoric acid; insoluble lead compound/lead phospate; ion exchange; adsorption;
2 marks Explain why a temperature inversion can trap pollutants close to ground level.
Air/pollutants cooler than air above (inversion layer)/cooler air trapped below warmer air; so less buoyant/more dense and cannot rise;
Explain why a temperature inversion can trap pollutants close to ground level. 2 marks
Air/pollutants cooler than air above (inversion layer)/cooler air trapped below warmer air; so less buoyant/more dense and cannot rise; [R pollutants cannot rise]
All scientific studies should be planned to use standardised techniques that produce reliable results. Suggest other variables that should be taken into account to assess whether the results were only caused by exposure to noise. 4 marks
Any other variables affecting whole groups;;;; eg other pollutants eg lead range of educational abilities quality of teaching class resources effect of peers socio-economic circumstances learning environment gender length of previous study temperature state of health time of day
Outline the arguments for and against the development of the following energy resources. 3 (c) (i) solar power 4 marks
Arguments for;;; max 3 renewable energy (relatively) simple technology no fuel requirement no pollution (in use) usable in isolated areas suitable for mobile uses few aesthetic problems Qualified comments that can be used for or against level of public support level of CO2 emissions none in use released during manufacture type of energy produced - suitability for public/industrial/transport use raw material usage installation/set-up costs maintenance costs Argument against;;; max 3 intermittent/day-night/seasonal Unreliable/affected by cloud cover Low efficiency (energy conversion by panels) Additional explanatory comments
Outline the arguments for and against the development of the following energy resources. 3 (c) (i) Nuclear power 4 marks
Arguments for;;; max 3 eg abundant fuel high energy density/small amount of fuel needed low fuel transport requirement named pollutant not released small waste quantity Qualified comments that can be used for or against eg mining damage uranium, sand, gravel, other materials site suitability limited number/planning permission problems lower access problems than fossil fuel P Stns development/installation/construction cost power station operation cost high cost compared with others high cost but high return type of energy produced - suitability for public/industrial/transport use level of technology well developed too complex for LEDCs level of CO2 emissions none from power stations lots from support industries power station aesthetics ugly power stations local impact worker safety good safety record public safety named health risk environmental contamination low contamination rate need for evacuation/changed land use stated damage caused level of public support perceived risks NIMBY employment Arguments against;;; max 3 eg non-renewable fuel decommissioning cost (reactor) accidents/Chernobyl/Windscale/Three Mile Island radioactive waste - lack of long-term disposal method radioactive waste - persistence/(long) half life radioactive waste - high cost of disposal weapons link/terrorism risk Additional explanatory comments
Suggest how the production of a named pollutant, other than smoke, may be reduced by the use of a named secondary fuel. [1 mark]
CO2/SO2/NOx/CO/HCs/radioactive waste/named pollutant not released [R smoke] and named secondary fuel (eg electricity, hydrogen) for named use;
Describe how lead effects human health 2 marks
Can effect enzyme activity or denature enzymes. Ingested lead can damage CNS , lower IQ and cause kidney disease
Outline method to reduce emissions of NOx 2 marks
Catalytic converter; platinum/palladium; reduction; oxygen + nitrogen produced; lean burn engine; control of oxygen supply; urea/ammonia treatment; named product/N2 (+ H2O CO2); named legislation; eg MOT emission controls UN Convention on Long Range Transboundary Pollution European Pollutant Emission Register (EPER) reporting requirements named alternative method/alternative fuel/energy conservation; [A two methods or one method + detail] [Cancel right and wrong answers if a list is given]
Use the problems identified in the article to describe the main features of a good scientific study to investigate the effects on humans of a chemical that is released into the environment. 10 marks
Clear hypothesis; (large) number of samples/repeats; avoid anomalous results/gain reliable results; allow statistical assessment of significance; need to control/measure impact of other variables; age; state of health; gender; occupation; other activities; other causes of health change; exposure to other chemicals; synergistic effects; toxic metabolites; critical group; Critical Pathway Analysis/route into body; accuracy of dose/concentration/exposure measurements; lack of knowledge of previous exposure; (equipment) calibration; need for range of doses/concentrations; timescale of study/chronic, acute effects; difficulty with controlled experiment; ethics of human testing/deliberate exposure; untestable hypotheses eg lethal human dose; transferability of results from animal testing; subjective measurement of symptoms/self-reporting; use of placebo/double blind tests; lack of comparison with other studies; need for peer assessment/objectivity; safety precautions;
Kyoto Protocol Critical Group Monitoring (CGM) Montreal Protocol Critical Pathway Analysis Financial charges made for the disposal of waste in landfill sites. Clean Air Act (1956) 5 marks fill in
Control of greenhouse gases/named greenhouse gas/carbon/climate change ; Study of group of (public) most at risk (because of their lifestyle) [R source-related occupational workers] Montreal Protocol Ban/control/reduction of ozone depletion/release of ODSs/named ODS eg CFCs ; Landfill Tax Financial charges made for the disposal of waste in landfill sites ; Clean Air Act (1956) Control of smoke pollution/smog/smokeless fuels/smokeless zones/smoke control areas ; 5 Total 5
4 marks Describe ways in which acid rain can harm plants.
Denatures proteins/enzymes; example of damaged tissue; - leaf/root detail of specific damage; - chlorosis/photosynthesis/pathogens/herbivores Inhibits nutrient uptake; example of nutrient action; description of ion exchange/competition; [only credit one isolated factor with no description] Nutrient leaching; reference to Ca/Mg/other nutrient; reduced growth; named soil organisms harmed; how plants are affected; solubility/mobilisation of toxic ions; e.g. of toxic ion: A13+, Pb+; enzyme inhibition;
Outline the differences between smoke smogs and photochemical smogs. [5 marks]
Differences: involvement of sunlight/UV in photochemical smog; incomplete combustion of named material for smoke smog eg fossil fuel, coal, oil, diesel, rubbish, wood; combustion/vaporisation of vehicle fuel for photochemical smog; details of process;; SPM/PM10/SO2 mixed in fog (smoke smog) [R unqualified particles] (unburnt) hydrocarbons/NOx (photochemical smog) secondary pollutants/ozone/PANs (photochemical smog) [A correct chemical equation for photochemical smog for 2 marks]
Outline the difference in the risks to public health of exposure to alpha and gamma radiation. 2 marks
Distance of travel from source; alpha shorter/gamma longer; OR ease of penetration/absorption; correct reference to alpha/gamma; OR effect of ingestion of source on health risk; greater increase for alpha radiation; OR ionising power; alpha high/gamma low;
Describe the general features which make species suitable to be used in a Biotic Index. 4 marks
Easy to catch/find; easy to identify/recognise/difficult to confuse; normally present/common/widely distributed; presence or absence indicates level of pollution/other named factor; differing species sensitivities to pollution/named factor/tolerance; predictable order of species appearance/disappearance; named species/taxon to illustrate sensitivity;
Describe the general features which make species suitable to be used in a Biotic Index. 4 marks
Easy to catch/find; easy to identify/recognise/difficult to confuse; normally present/common/widely distributed; presence or absence indicates level of pollution/other named factor; differing species sensitivities to pollution/named factor/tolerance; predictable order of species appearance/disappearance; named species/taxon to illustrate sensitivity; MAX 4
Describe the likely effects of mercury on herons 2 marks
Effects nervous system Cause paralysis
Explain how a temperature inversion may trap pollutants close to ground level and prevent their dispersal 3 marks
Emissions are cooled/lower are is colder; become more dense/air is more dense; less buoyant;
Name the government responsible for monitoring and controlling water and air pollution? 1 mark
Environment agency
Outline how ozone is environmentally important in the following. 2 (a) (i) directly affecting living organisms 1 mark
Eye/respiratory/asthma/leaf-cuticle damage; [R protection from UV]
Outline the factors that influence the per capita energy consumption in different countries. 6 marks
Factors;;;; linked detail;;; eg affluence named energy using device/items that require energy in manufacture eg cars, washing machine, jacuzzi, metals/plastics level of industry more industry for named reason eg mineral resources, water availability, workforce type of industry 1o /2o /3o /4o /metal processing/chemicals/agriculture/manufacturing/ services climate heating in cold (climates)/cooling in hot (climates) environmental awareness (high) encouraging conservation/(low) encouraging waste indigenous energy resources/supply infrastructure/cheaper supplies allows greater use/named energy expensive use
Outline the ways in which the use of wind turbines may cause damage to the natural environment. 3 marks
Habitat damage during material extraction/processing; habitat loss/damage for installation of aerogenerators; habitat loss/damage for access roads/transformers/cables/infrastructure; aesthetic damage to natural environment; bird strike; bat deaths; noise disturbance of wildlife/named taxa; eg of cetaceans
Outline a method used in power stations to reduce the temperature of effluent water. 1 mark
Hot water spray in cooling towers/heat passes to air in cooling towers/district heating/heat exchanger;
1 mark Outline a method used in power stations to reduce the temperature of effluent water.
Hot water spray in cooling towers/heat passes to air in cooling towers/district heating/heat exchanger; [R 'cooling towers' with no details]
Explain the significance for aquatic life of the relationship between dissolved oxygen and temperature shown in the graph. (as temp increases dissolved o2 down) 3 marks
Increased temperature reduces solubility/concentration/availability/level of oxygen; oxygen driven off if water is already saturated/if water temperature rises oxygen levels decline; DO level may drop below that necessary for organisms to survive/thrive; need for special adaptations to low DO; greater species diversity at lower temp/higher DO; more competition at lower temp/higher DO;
Outline how ozone is environmentally important in the following. 2 (a) (i) photochemical smogs 1mark
Interaction with NOx/HCs/production of PANs; [A interaction with sunlight]
Explain what is meant by the term production loop.
Internal recycling/recycling within the industry which produced the material;
Discuss the methods used to treat solid wastes to reduce pollution. (20 marks)
Landfill: relatively cheap no processing land use methane release leachate Incineration: reduced solid waste atmospheric pollutants heat recovery equipment costs named wastes named processes Recycling: reduced resource use reduced processing cost reduced wastes transport costs labour costs named wastes 14 named processes
Use examples to explain the following terms, as applied to pollution. (a) Persistence. (2 marks)
Length of time a pollutant remains in environment (before it degrades/breaks down); [A description based on more persistent] example of pollutant to illustrate - organochlorines/PCBs/CFCs/dioxins/sewage/radioisotopes or other suitable example; 2 [R pollutants that don't degrade]
Turbine A, with the helical blades, rotates more smoothly than Turbine B. It suffers lower stresses, so it does not need to be as strong and can be lighter than Turbine B. 2 (a) Suggest how making lighter turbines may reduce environmental damage.
Less energy use/pollution/habitat damage/material used; reason; eg extraction processing (raw materials) manufacture transport installation disposal at end of life [R less noise, fewer bird strikes]
Explain how lichens may be used as biological indicators of atmospheric acid pollution 2 marks
Lichens are sensitive to SO2 concentrations. Therefore certain lichens are present at certain concentrations of SO2
What are the properties of pollutants which make concentration along the food chain likely 2 marks
Liposoluble and can accumulate in tissues Dissolve in water and can diffuse across membranes
4 marks The photograph shows an area used to test aircraft engines at an airport. The test area is surrounded by acoustic screens and is located away from nearby housing. 3 (a) Outline two other ways in which airport noise pollution is reduced.
Method;; linked detail;; 2 + 2 eg flight paths/no fly zones/airport location/buffer zone/aircraft activities noise away from residential areas flight timing avoid sensitive times/not at night (continuous) descent angle/CDA avoid increase in power named aerodynamic feature/fairings/moulded surfaces reduced turbulence high bypass ratio jet engines/wide diameter jet lower velocity exhaust gases engine hush kits mix exhaust gases with surrounding air lighter aircraft less powerful engines acoustic walls/baffle mounds/embankments/trees absorb/deflect sound [R blocks] double glazing noise absorbed [R blocks] ban/restrict noisy aircraft Concorde/named noisy aircraft/low bypass ratio jets
Suggest how the half-life of iodine 131 may make it a greater risk to public health than plutonium 239. 1 marks
More energy/radiation released/absorbed/ionising events/free radicals per unit time;
Explain the relationship shown by the graph 2 marks as cost of pollution control increases pollution prevented increases
More money spent means more pollution prevented/+ve correlation with increasing gradient/exponential relationship/cost per unit pollution control increases; very difficult/impossible/too expensive to prevent all pollution; money spent on pollution control becomes incrementally less effective; cost of pollution control equipment increases with its efficiency;
Explain how economic strategies have been used to encourage the use of renewable energy. 3 marks
NFFO/Non Fossil Fuel Obligation; price control; eg increase fossil fuel price tax relief; carbon tax; (set-up) grants/discounts/subsidies/loans/research funding; make planning process/construction easier; sell surplus electricity to the grid;
Suggest two reasons why wind farms are not always built in the windiest areas. 2 marks
Named human conflicts;; eg aesthetics, noise, flicker, radio interference named wildlife conflicts;; eg bird strike/migration route, bat deaths, habitat damage designated areas access difficulty; distance to consumers; named construction problem; eg poor foundations/deep water
Outline one method that is used for the storage of high level radioactive waste from nuclear power stations. 2 marks
Named method; detail of method;; eg vitrification/encapsulation cooling pond/water (dried) powder (solid) glass stainless steel container concrete/other absorbing material air/gas cooling (of separated high level waste) deep burial geologically/seismically stable area hydrological isolation/impermeable rock/salt caverns
Explain why it would be difficult to use coal to replace petroleum. (1 mark)
Named unsuitable feature of coal; eg solid, flow problems [A lower energy density] OR named use of petroleum/necessary feature of petroleum; eg vehicle fuel, petrochemicals, fluid, ease of flow, wider range of chemical raw materials
Outline two beneficial uses of radioactive isotopes. 1. 2. (4 marks)
Names of uses - for 1 mark description of use - for 1 mark example of isotope - for 1 mark [R description of activity alone] Cancer treatment; turbine testing; smoke detectors; beta lights; roll steel/paper thickness testing; pathway analysis; radiolabelling; autoradiography; nuclear power stations; ship propulsion reactors; pest control; food sterilisation; (isotope) dating/aging; barium meals;
Describe how inorganic nutrients entering a lake may lead it to become deoxygenated? 4 marks
Nitrates and phosphates Algae bloom Algae uses up O2 by aerobic respiration Plants die due to lack of sunlight from shading due to algae Decomposition uses up oxygen available in lake and causes deoxygenation
describe how the inorganic nutrients present in sewage effluent may also cause deoxygenation of rivers 2 marks
Nitrates and phosphates Algae bloom Algae uses up O2 by aerobic respiration Plants die due to lack of sunlight from shading due to algae Eutrophication
Suggest why using a Biotic Index may be preferred to measuring pollutants directly 2 marks
No expensive/complicated equipment required; gives estimates of past pollution; gives longer-term measure if pollutant fluctuates; gives measure of effect not causes; instant results/quicker; cost effective; no need to identify/monitor specific pollutants;
Suggest why using a Biotic Index may be preferred to measuring pollutants directly. 2 marks
No expensive/complicated equipment required; gives estimates of past pollution; gives longer-term measure if pollutant fluctuates; gives measure of effect not causes; instant results/quicker; cost effective; no need to identify/monitor specific pollutants;
Explain why drainage water from metal mine spoil heaps is often acidic 2 marks
O2 reacts with sulfur compounds in the mine, present in rocks These get oxidised to sulfur dioxide and react with water to form sulfur if acid
Outline three ways in which an individual's exposure to ionizing radiation may be very different from the averages shown in the diagram. 1. (1 mark) 2. (1 mark) 3. (1 mark)
Occupational variation - radiologist/nuclear energy/researcher/nuclear manufacturing/mining more air travel absorbing cosmic rays/radiation; public exposure to radioactive pollution/weapons fall-out; diet rich in radioactive isotopes; women - more Potassium 40; recreational exposure e.g. potholing; medical treatments e.g. radiotherapy/X rays; garden peat; location/local geology - differing radioisotope levels;
Outline how ozone is environmentally important in the following. 2 (a) (i) Suggest how the low persistence of ozone effects severity of pollution it causes 1 mark
Only short-term/local effects effects/reduced mobility;
Name the three main pollutant gases which react during photochemical smogs to produce Peroxy Acetyl Nitrates (PANs). 1 mark
Oxides of nitrogen/NOx; AND Hydrocarbons/VOCs/sunburnt vehicle fuel; AND ozone;
Outline how ozone is environmentally important in the following. 2 (a) (i) Acid rain 1 mark
Oxidises SO2 to SO3/sulfurous acid to sulfuric acid/synergism/toxic to leaves-cuticles/denatures proteins - cell membranes/chlorosis;
Describe how soil acidification can harm plants 5 marks
Plant enzymes denature due to change in pH Deflocculation of soils lead to leached minerals not be able to take up these nutrients Heavy metals increase solubility Heavy metals taken up by plants
Purpose of aeration 1 mark
Promote aerobic respiration to breakdown inorganic matter
Explain how the electricity industry can store surplus energy to help match fluctuations in demand. 5 marks
Pumped storage HEP; (surplus electricity used to) pump water up; two reservoirs; (gravitational) potential energy; water released during periods of demand; rapid response; HEP dam kept closed; (gravitational) potential energy (stored); electricity generated when required; Hydrogen economy; (surplus electricity used for) electrolysis of water; storage of hydrogen (from electrolysis); use of (stored) hydrogen when needed; named method of using (stored) hydrogen; Fuel cell; electricity used to make fuel/converted to chemical energy; named fuel/hydrogen/methanol; electricity generated when required; named use of fuel cell;
Explain how lichens can be used to monitor atmospheric pollution. 4 marks
Range/type/number of species; named species; (differing) sensitivities/named acidic pollutant; presence/absence/abundance; colour; size/state of health; reproductive structures; location of study sites; eg urban/rural transect, gravestones number of samples (for reliable results); estimate of past pollutant levels;
explain the effect that low oxygen levels have on biodiversity of aquatic ecosystems 2 marks
Reduce number of species low tolerance range different oxygen requirements
Describe how catalytic converters in vehicle exhausts help prevent photochemical smogs 2 marks
Reduction/conversion; of NO x; to Nitrogen; oxidation; of hydrocarbons/conversion; to H2O and CO2; prevents production of secondary pollutants/Peroxy Acetyl Nitrates/PANs;
Describe how catalytic converters in vehicle exhausts help prevent photochemical smogs 2marks
Reduction/conversion; of NOx; to Nitrogen; oxidation; of hydrocarbons/conversion; to H2O and CO2; prevents production of secondary pollutants/Peroxy Acetyl Nitrates/PANs; MAX 2 [R smog] [R CO → CO2]
Complete the table. Process Purpose Principle of operation Screening Primary sedimentation Aeration Tertiary treatment Anaerobic digestion 5 marks
Removal of gross/large solids/paper/plastic [R grit] Separation/removal of (suspended) solids/organic matter (from fluids) [R grit] Breakdown/digestion of organic matter/activation of (aerobic) bacteria [R water treatment] Removal of phosphates/production of iron phosphate Breakdown of organic matter or sludge/ volume reduction/ odour removal/ bacteria/pathogen removal
Explain how the characteristics of a river may affect the severity of pollution caused by effluents. 3 marks
River volume/cross sectional area and its ability to dilute; velocity/residence time and its ability to disperse; turbulence and its effect on dissolved oxygen; pH and its effect on pollutant activity; river organisms and their effect on biodegradation/pollutant activity; DO levels and their effect on pollutant degradation/reactions; temperature and its effect on pollutant activity; 1 example of appropriate pollutant;
Outline the use of the following in monitoring pollution caused by radioactive materials. (i) Environmental sampling (3 marks) (ii) Critical Group Studies (3 marks) (iii) The Nuclear Installations Inspectorate (3 marks
Samples selected where radioisotopes may be most concentrated; samples of importance to humans; [R human tests] samples of widespread/easy to collect materials; samples chosen to identify pathways; detect changes over time; e.g. of sampled material. MAX 3 (water/soil/vegetation/air/dust/animals or other suitable example) (ii) Members of public/humans; who have lifestyles/details of lifestyle; [R young/old] [R occupational activities] which put them at particular risk/most likely to be affected; if they are safe then all others should be; MAX 3 (iii) Statutory body/government regulations; check (safe) working practices; check (safe) waste disposal; check (safe) discharges; check (safe) transport; issue site licences/authority to close establishments;
Explain how Biotic Indices may be used to monitor pollution. 6 marks
Sensitivity (of organisms) to pollution; named pollutant; named biotic index/Trent/BMWP; long timescale monitoring; range of species with different sensitivities/tolerance; lichens/aquatic invertebrates/named taxon; presence/absence; abundance (as indicator of pollution); size/state of health/reproductive structures/appearance; easy to find/catch; normally abundant (if no pollution); easy to identify; normally present; evenly distributed; standardised substrate/aspect; size of sample area; sample locations (range of pollution levels, above/below source); calculation of scale/index;
Explain why radioactive materials which emit alpha radiation are relatively safe when outside the body but are very dangerous if ingested. 2 marks
Short range in/easily absorbed by clothing/dead cells on outside of body; chemical change/ions/genetic change/produce free radicals in/cause fatal mutations in/cause cancerous growth of living cells inside body;
Suggest why wind power is particularly suitable for electricity generation in remote areas. 2 marks
Small scale generation/simple installation possible; (small enough for) easy transport; no fuel inputs; low maintenance; energy transport infrastructure not present; less energy loss in long distance transport; fewer people that may object/affected; less interference with radio/radar/microwave links; [R remote areas windier]
Explain how electrostatic precipitators are used to control pollution. 2 marks
Smoke/particles; charge difference/(particles) attracted; ash collected/falls/removed;
What is the source of the energy which causes the chemical reactions during a photochemical smog? 1 mark
Solar energy/nuclear fusion/sunlight/sun;
Explain why some buildings may have higher than average levels of radon. 2 marks
Some buildings are built of/on granite; granite contains uranium; (granite/uranium) decays to give radon; (closed structure) traps radon;
Outline an example in which finding a use for a waste material has helped to reduce pollution.Electrolytic separation of copper wastes; Less copper effluent to rivers; OR Paper waste recycling; less anaerobic methane production/less litter/burning; OR Car tyres for fuel/chipped rubber products; less burning leading to smoke/sulphurous fumes; OR Methane from sewage/landfill; fuel/burnt for heat/electricity; OR Sewage; fertiliser; OR Sulphur gases (and limestone); gypsum/plaster; OR other suitable example MAX
Specific example of use of waste material giving rise to reduction in named pollutant/polluting activity
Outline an example in which finding a use for a waste material has helped to reduce pollution. 1 mark
Specific example of use of waste material giving rise to reduction in named pollutant/polluting activity;Electrolytic separation of copper wastes; Less copper effluent to rivers; OR Paper waste recycling; less anaerobic methane production/less litter/burning; OR Car tyres for fuel/chipped rubber products; less burning leading to smoke/sulphurous fumes; OR Methane from sewage/landfill; fuel/burnt for heat/electricity; OR Sewage; fertiliser; OR Sulphur gases (and limestone); gypsum/plaster; OR other suitable example
Purpose of screening 1 mark
Stop large materials from clogging of pipes further downstream e.g branches
Describe the ways in which the release of two named gases which cause acid rain may be controlled. Gas Control method (4 marks) Gas Control method (4 marks)
Sulphur dioxide/trioxide/SO2/SO3; (wet flue-gas) desulphurisation/Wellman-Lord process/scrubbing; dissolved/reacted with; water/sodium sulphite solution; sulphur/sulphuric acid recovered (as raw material)/recycled; OR Sulphur dioxide/trioxide/SO2/SO3; (dry flue-gas) desulphurisation; react with lime/limestone/calcium carbonate; produce solid gypsum/calcium sulphate; dumped/used to make building plaster; OR Oxides of nitrogen/NOx or specific example; catalytic converters; example of catalyst/paladium/platinum; chemical reduction of NOx; production of nitrogen (gas); [R lean burn engines] OR Oxides of nitrogen/NOxor specific example; urea; reduction of NOx; production of nitrogen gas; OR Ozone/O3; produced from breakdown of NOx; prevent release of NOx; name/detail of method above; [R Alternative activities e.g. energy conservation, renewable resources]
Describe the effect that acid drainage water may have on the wildlife in the river 2 marks
The acidic water may leach into water and cause a change in ph that may denature enzymes. Acidic waters harm organisms which have exoskeletons that are made of calcium carbonate
Explain why polluters are often reluctant to invest money in pollution prevention. 1 mark
They do not get the benefit (of the pollution prevention so will not invest without compulsion); (unnecessary expenditure) makes them less competitive; cost: benefit; reduced profit margin; MAX 1 [R expensive]
Explain the differences between the following terms that are used to describe the effects of ionising radiation on human health. (2 marks) 4 (c) (ii) Acute and chronic effects
Timescale; acute - short; chronic - long;
Discuss the methods that can be used to reduce the energy used in transport systems and industry. (20 marks)
Vehicle design: Aerodynamics wheel design ignition cooling appliances eg AC weight manufacture materials regenerative braking/hybrid engines Vehicle use: speed control/acceleration encouragement of bicycle/public transport use/car share financial incentives/disincentives Industry: thermal insulation volume control heat recovery
Give a major source of lead pollution and one major pathoway this lead can enter human body 2 marks
Vehicles that use leaded petrol emit lead into atmosphere. Gaseous lead produced by the burning of fossil fuels can be breathed in by humans.
Explain how the severity of pollution can be affected by the features of the environment into which pollutants are released. (20 marks)
Water flow/currents water velocity current direction depth enclosed water bodies/water volume air flow/wind wind strength wind direction precipitation (precipitation) patterns/intermittency/amount geology porosity topography permeability pH wildlife named sensitive taxa
Outline method to reduce emissions of SO2 2 marks
Wet/dry flue gas desulfurisation/FGD/fluidised bed; lime/calcium carbonate/calcium oxide; slurry/wet spray/scrubber; calcium sulfate/gypsum; Wellman Lord; scrubber; sodium sulfite; sulphuric acid; coal desulfurisation; crush and wash/stream; hydrodesulfurisation; (conversion to) H2S; amine solution; biodesulfurisation; named taxon; eg Rhodococcus named legislation; eg UN Convention on Long Range Transboundary Pollution European Pollutant Emission Register (EPER) reporting requirements Clean Air Act (1956) UK's Air Quality Strategy Protocol on the Reduction of Sulphur Emissions named alternative method/ alternative fuel/energy conservation; [A two methods or one method + detail] [Cancel right and wrong answers if a list is given]
State one major factor that affects the maximum potential for future expansion of the following renewable energy resources. 6 (d) (i) Wind (1 mark)
Wind - public objection/unreliable/intermittent/low wind velocity/ named ecological land use conflict; [A named technological development]
outline the process by which sewage can conduct electricity 6 marks
anaerobic warm/wet conditions large surface area methane dried and burnt steam generated turbine role of generator
Describe the factors that make it more likely that a temperature inversion will occur. [3 marks]
anticyclonic system/high pressure; low wind speed; valley; clear sky; night time;
Describe how organic matter in sewage causes deoxygenation of rivers 1 mark
bacteria respiration
Purpose of anareobic digestion 1 mark
breakdown of sludge
Suggest why permitted releases of water are lower in summer than in winter 2 marks
high temp in summer/less dilution/FASTER decay/ more rapid deoxygenation
What is 2 methods of disposal of sludge and give one advantage and 1 disadvantage for each 6 marks
incineration - removes and kills remaining pathogens - nutrients wasted landfill - cheap and easy to do - leaching of nutrients into water body fertilizer use - nutrients are not wasted - difficult to apply to crops
Purpose of tertiary treatment 1 mark
remove phosphates from effluent
A new design of battery is the 'bio-battery'. This design is based on glucose rather than on metals such as lead, nickel or cadmium. Suggest three advantages of using bio-batteries rather than batteries based on metals. [3 marks]
renewable (energy source); instant refuelling possible; lower embodied energy; less named resource extraction damage/more abundant; biodegradable; named environmental problem associated with use of metal;; eg no neurotoxins no bioaccumulation no biomagnification no synergism named lower cost feature; eg resource extraction waste disposal recycling
Purpose of primary sedimentation 1 mark
to separate out sediments (OM) that are suspended in water
describe the precautions that should have been taken in the water sampling procedure that would have ensured a fair test 4 marks
up to 3 aspects of standardized sampling techniques same time of day due to O2 fluctuations same depth rinse tube in river water
Describe a method that could be used to measure biochemical oxygen demand 3 marks
water sampling preparation collected in sealed container dilution series samples divided for measurement before and after contains no air space stored in dark for 5 days at 20 degrees electronic meter
Give one method used in industry to protect workers from lead. [1 mark]
water sprays/air filter/respirator/gloves/cover exposed skin/remote operation/reduced time of exposure/regular blood tests