Unit 8: Aquatic and Terrestrial Pollution covers human impacts on land and water systems. On the APES exam, this unit is often tested through data interpretation, cause-and-effect chains, and policy connections.
This RevisionDojo review breaks down what you need to know for MCQs and FRQs.
🌊 Key Topics in Unit 8
- Types and sources of water pollution
- Eutrophication and dead zones
- Point vs. nonpoint sources of pollution
- Oil spills and heavy metals
- Plastic and solid waste
- Sewage treatment
- Hazardous waste management
- Laws and policies (Clean Water Act, CERCLA, etc.)
💧 Point vs. Nonpoint Source Pollution
Point source: Pollution from a single, identifiable source
- Examples: Factory discharge, wastewater treatment plants
Nonpoint source: Diffuse, widespread pollution
- Examples: Runoff from farms, stormwater carrying oil
🧪 Water Pollution Types
- Nutrient pollution: Excess nitrogen & phosphorus → eutrophication
- Pathogens: Bacteria, viruses from sewage
- Toxic chemicals: Pesticides, heavy metals, industrial waste
- Sediment pollution: Soil erosion → cloudy water, habitat loss
🌱 Eutrophication
- Process: Nutrient runoff → algal bloom → oxygen depletion → fish kills
- Human acceleration: Fertilizer use, untreated sewage
- Solution: Reduce nutrient input, buffer strips, wetland restoration
🛢 Oil Spills
- Sources: Tanker accidents, offshore drilling
- Impacts: Coats animals, blocks sunlight, toxic ingestion
- Cleanup: Skimming, dispersants, bioremediation
🗑 Solid & Hazardous Waste
- Solid waste: Mostly landfill or incinerated; plastics are persistent pollutants
- Hazardous waste: Toxic, reactive, ignitable, or corrosive materials
- Management: RCRA (resource conservation), CERCLA/Superfund (cleanup)
🚰 Sewage Treatment
- Primary treatment – Physical removal of solids
- Secondary treatment – Biological breakdown of organic matter
- Tertiary treatment – Nutrient removal, disinfection
📜 Key Laws & Policies
- Clean Water Act (1972) – Regulates discharges, sets water quality standards
- Safe Drinking Water Act – Protects public drinking water
- CERCLA/Superfund – Cleans hazardous waste sites
🧠 APES Exam Tips for Unit 8
- Always identify source → impact → solution in FRQs.
- Practice interpreting water quality indicators (DO, BOD, pH, nitrates).
- Know major U.S. environmental laws by name and purpose.
- Be able to explain waste treatment processes in order.
💡 FAQ – Unit 8: Aquatic & Terrestrial Pollution
Q: What’s the biggest cause of dead zones?
A: Nutrient pollution leading to eutrophication.
Q: Which law deals with hazardous waste cleanup?
A: CERCLA (Superfund).
Q: How can plastic pollution be reduced?
A: Reduce single-use plastics, improve waste collection, promote biodegradable alternatives.
Final Word from RevisionDojo:
Unit 8 is all about connecting pollution sources to their environmental and human health impacts. On the exam, be ready to suggest realistic mitigation measures and back them with scientific reasoning.
